[{"awards": "2142914 Baker, Bill; 2142913 Tresguerres, Martin; 2142912 Murray, Alison", "bounds_geometry": "POLYGON((-180 -60,-168 -60,-156 -60,-144 -60,-132 -60,-120 -60,-108 -60,-96 -60,-84 -60,-72 -60,-60 -60,-60 -62,-60 -64,-60 -66,-60 -68,-60 -70,-60 -72,-60 -74,-60 -76,-60 -78,-60 -80,-72 -80,-84 -80,-96 -80,-108 -80,-120 -80,-132 -80,-144 -80,-156 -80,-168 -80,180 -80,178 -80,176 -80,174 -80,172 -80,170 -80,168 -80,166 -80,164 -80,162 -80,160 -80,160 -78,160 -76,160 -74,160 -72,160 -70,160 -68,160 -66,160 -64,160 -62,160 -60,162 -60,164 -60,166 -60,168 -60,170 -60,172 -60,174 -60,176 -60,178 -60,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 17 Oct 2024 00:00:00 GMT", "description": "Non-technical description\u003cbr/\u003eMarine invertebrates often have mutually beneficial partnerships with microorganisms that biosynthesize compounds with nutritive or defensive functions and are integral for survival. Additionally, these \u201cnatural products\u201d often have bioactive properties with human health applications fighting infection or different types of cancer. This project focuses on the ascidian (\u201csea squirt\u201d) Synoicum adareanum, found in the Anvers Island region of the Antarctic Peninsula, and was recently discovered to contain high levels of a natural product, palmerolide A (palA) in its tissues. The microorganism that produces palA is a new bacterial species, Candidatus Synoicihabitans palmerolidicus, found in a persistent partnership with the sea squirt. There is still much to be learned about the fundamental properties of this sea squirt-microbe-palA system including the geographical range of the animal-microbe partnership, its chemical and microbiome complexity and diversity, and the biological effect of palA in the sea squirt. To address these questions, this multidisciplinary research team will investigate the sea squirt-microbiome partnership in the Antarctic Peninsula and McMurdo Sound regions of the Ross Sea using a state-of-the-art strategy that will advance our understanding of the structural and functional features of the sea squirt and microbiome in detail, and reveal the roles that the palA natural product plays in the host ecology in its native Antarctic seafloor habitat. The project will broaden diversity and provide new opportunities for early career students and postdoctoral researchers to participate in field and laboratory-based research that builds an integrative understanding of Antarctic marine biology, ecology, physiology and chemistry. In addition, advancing the understanding of palA and its biological properties may be of future benefit to biomedicine and human health.\u003cbr/\u003e\u003cbr/\u003eTechnical description\u003cbr/\u003eMarine invertebrates and their associated microbiomes can produce bioactive natural products; in fact, \u003e600 such compounds have been identified in species from polar waters. Although such compounds are typically hypothesized to serve ecological roles in host survival through deterring predation, fouling, and microbial infection, in most cases neither the producing organism nor the genome-encoded biosynthetic enzymes are known. This project will study an emerging biosynthetic system from a polar ascidian-microbe association that produces palA, a natural product with bioactivity against the proton-pumping enzyme V-type H+-ATPase (VHA). The objectives include: (i) Determining the microbiome composition, metabolome complexity, palA levels, and mitochondrial DNA sequence of S. adareanum morphotypes at sites in the Antarctic Peninsula and in McMurdo Sound, (ii) Characterizing the Synoicum microbiome using a multi-omics strategy, and (iii) Assessing the potential for co-occurrence of Ca. S. palmerolidicus-palA-VHA in host tissues, and (iv) exploring the role of palA in modulating VHA activity in vivo and its effects on ascidian-microbe ecophysiology. Through a coupled study of palA-producing and non-producing S. adareanum specimens, structural and functional features of the ascidian microbiome metagenome will be characterized to better understand the relationship between predicted secondary metabolite pathways and whether they are expressed in situ using a paired metatranscriptome sequencing and secondary metabolite detection strategy. Combined with tissue co-localization results, functional ecophysiological assays aim to determine the roles that the natural product plays in the host ecology in its native Antarctic seafloor habitat. The contributions of the project will inform this intimate host-microbial association in which the ascidian host bioaccumulates VHA-inhibiting palA, yet its geo-spatial distribution, cellular localization, ecological and physiological role(s) are not known. In addition to elucidating the ecophysiological roles of palA in their native ascidian-microbe association, the results will contribute to the success of translational science, which aligns with NSF\u2019s interests in promoting basic research that leads to advances in Biotechnology and Bioeconomy. The project will also broaden diversity and provide new opportunities for early career students and postdoctoral researchers to participate in field and laboratory-based research that builds an integrative understanding of Antarctic marine biology, ecology, physiology and chemistry.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": 160.0, "geometry": "POINT(-130 -70)", "instruments": null, "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; BACTERIA/ARCHAEA; BENTHIC; R/V NBP; Antarctic Peninsula; ANIMALS/INVERTEBRATES", "locations": "Antarctic Peninsula", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Baker, Bill; Murray, Alison; Tresguerres, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repositories": null, "science_programs": null, "south": -80.0, "title": "Collaborative Research: ANT LIA: Diving into the Ecology of an Antarctic Ascidian-Microbiome-Palmerolide Association using a Multi-omic and Functional Approach", "uid": "p0010485", "west": -60.0}, {"awards": "1841228 Lyons, W. Berry", "bounds_geometry": "POLYGON((163.37428 -77.558627,163.3922735 -77.558627,163.410267 -77.558627,163.4282605 -77.558627,163.446254 -77.558627,163.4642475 -77.558627,163.482241 -77.558627,163.5002345 -77.558627,163.518228 -77.558627,163.5362215 -77.558627,163.554215 -77.558627,163.554215 -77.56397510000001,163.554215 -77.5693232,163.554215 -77.5746713,163.554215 -77.5800194,163.554215 -77.5853675,163.554215 -77.59071560000001,163.554215 -77.5960637,163.554215 -77.60141180000001,163.554215 -77.6067599,163.554215 -77.612108,163.5362215 -77.612108,163.518228 -77.612108,163.5002345 -77.612108,163.482241 -77.612108,163.4642475 -77.612108,163.446254 -77.612108,163.4282605 -77.612108,163.410267 -77.612108,163.3922735 -77.612108,163.37428 -77.612108,163.37428 -77.6067599,163.37428 -77.60141180000001,163.37428 -77.5960637,163.37428 -77.59071560000001,163.37428 -77.5853675,163.37428 -77.5800194,163.37428 -77.5746713,163.37428 -77.5693232,163.37428 -77.56397510000001,163.37428 -77.558627))", "dataset_titles": "Commonwealth Stream Diel Water Chemistry", "datasets": [{"dataset_uid": "601844", "doi": null, "keywords": "Antarctica; Commonwealth Stream; Cryosphere; Diel; Inlandwaters; McMurdo Dry Valleys; Stream Chemistry; Water Chemisty", "people": "Gardner, Christopher B.", "repository": "USAP-DC", "science_program": null, "title": "Commonwealth Stream Diel Water Chemistry", "url": "https://www.usap-dc.org/view/dataset/601844"}], "date_created": "Wed, 16 Oct 2024 00:00:00 GMT", "description": "Phytoplankton, or microscopic marine algae, are an important part of the carbon cycle and can lower the rates of atmospheric carbon dioxide by transferring the atmospheric carbon into the oceans. The concentration of phytoplankton in the Southern Ocean is regularly limited by the availability of marine iron. This in turn influences the rate of carbon transfer from the atmosphere to the ocean. The primary source of iron in the Southern Ocean is eroded continental rock. Understanding the current and future sources of iron to the Southern Ocean as a result of increased melting of terrestrial glaciers is necessary for predicting future concentrations of Southern Ocean phytoplankton and the subsequent influence on the carbon cycle. A poorly understood source of iron to the Southern Ocean is stream input from ice-free regions such as the McMurdo Dry Valleys in Antarctica. This source of iron is likely to become larger if glaciers retreat. This study investigates the sources and amount of iron transported by McMurdo Dry Valley streams directly into the Southern Ocean. Because not all forms of iron can be used by phytoplankton, experiments will be performed to determine how available iron is to phytoplankton and how iron mixes with seawater. Immersive 360-degree video, infographics, and educational videos of findings from this project will be shared on social media, at schools and science events, and in an urban science center.\u003cbr/\u003e\u003cbr/\u003eIn the Southern Ocean (SO) there is an excess of macronutrients but regional primary production is limited or co-limited due to iron. An addition of iron to the ocean will affect biochemical cycles, increase primary production, and affect the structure and composition of phytoplankton communities in the SO. Iron flux to the SO is globally significant, as increased Fe fertilization leads to increased carbon sequestration which acts as a negative feedback to increased atmospheric pCO2. One source of potentially bioavailable iron to the coastal regions of the SO is from direct sub-aerial stream discharge in ice-free areas of Antarctica, a source that may become more important if terrestrial glaciers retreat. It is imperative to understand the source, nature, potential fate, and flux of iron to the SO if better predictive models for the carbon cycle and atmospheric chemistry are to be developed. This project will investigate in-stream processes and characteristics controlling dissolved iron draining into the Ross Sea including photoreduction, temperature, and complexation with organic matter. The novel study will quantify bioavailability of particulate iron and bioavailability of dissolved iron in Antarctic in streams draining into the SO. On-site speciation measurements will be performed on dissolved iron species, particulate iron speciation will be determined using high-resolution spectroscopy, mixing experiments will be performed with coastal marine water, and the bioavailability of Fe will be determined through marine bioassays. This project will provide two students with valuable Antarctic field experience and reach thousands of individuals through existing partnerships with K-12 schools, public STEM events, an urban science center, and a strong social media presence.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 163.554215, "geometry": "POINT(163.4642475 -77.5853675)", "instruments": null, "is_usap_dc": true, "keywords": "SURFACE WATER CHEMISTRY; Iron Fertilization; McMurdo Dry Valleys; Weathering", "locations": "McMurdo Dry Valleys", "north": -77.558627, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Lyons, W. Berry; Gardner, Christopher B.", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.612108, "title": "Fe Behavior and Bioavailability in Sub-aerial Runoff into the Ross Sea", "uid": "p0010483", "west": 163.37428}, {"awards": "2332479 MacAyeal, Douglas", "bounds_geometry": "POLYGON((161 -76,162.4 -76,163.8 -76,165.2 -76,166.6 -76,168 -76,169.4 -76,170.8 -76,172.2 -76,173.6 -76,175 -76,175 -76.3,175 -76.6,175 -76.9,175 -77.2,175 -77.5,175 -77.8,175 -78.1,175 -78.4,175 -78.7,175 -79,173.6 -79,172.2 -79,170.8 -79,169.4 -79,168 -79,166.6 -79,165.2 -79,163.8 -79,162.4 -79,161 -79,161 -78.7,161 -78.4,161 -78.1,161 -77.8,161 -77.5,161 -77.2,161 -76.9,161 -76.6,161 -76.3,161 -76))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 08 Oct 2024 00:00:00 GMT", "description": "Non-Technical Abstract:\u003cbr/\u003eThis project explores the areas or crash-zones where floating ice shelves in Antarctica compressively flow against obstructions such as islands and plugs of stagnant ice frozen to the sea bed. The significance of these crash-zones is that they are responsible for generating the resistive forces that allow ice shelves to slow down the flow of ice farther inland into the ocean. Ice conditions within these boundaries thus determine how Antarctica\u2019s ice sheets contribute to sea-level rise. The research will feature on-the-ice glaciological and geophysical field measurements near pressure ridges near Scott Base and the transition to the ice road where large wave-like pressure ridges form on the ice-shelf surface. This field area is along the coast of Ross Island adjacent to major logistical stations of the US and New Zealand Antarctic programs. Thus the research will help station managers better preserve one of the key roadways that connects the stations to the major runway used to fly to virtually all other parts of Antarctica. The research will also interact with educational programs such as featured in the long-standing Juneau Icefield Research Project as well as potential involvement of an artist from the US Antarctic Program\u2019s Polar STEAM in the second field season.\u003cbr/\u003e\u003cbr/\u003eTechnical Abstract:\u003cbr/\u003eThis project explores the dynamics of boundaries where ice shelves compressively flow against obstructions such as islands and areas of grounded ice. The significance of these boundaries is that they are responsible for generating the resistive forces that allow ice shelves to impede or slow down the flow of grounded inland ice into the ocean. Ice conditions within these boundaries thus determine how Antarctica\u2019s ice sheets contribute to sea-level rise. The research will feature glaciological and geophysical field surveys in a compressive boundary area near pressure ridges adjacent to Scott Base and the transition to the ice road along the coast of Ross Island, an area affecting access to major logistical hubs of the US and New Zealand Antarctic programs. Field data will be combined with remote sensing, numerical modeling and theory development to answer key questions about the dynamics of compressive boundaries such as: is there a limit to compressive stress due to ice fracture and the bending of the ice shelf into sinusoidal pressure ridges? Over what time scales does this compressive stress build, fluctuate and decay, and how is it related to the processes that form rumples? Are there ways in which the ridges actually protect the compressive boundary from damage such as by setting up a means to scatter ocean swell impinging from the open ocean? How should compressive ice-shelf boundaries be represented in large scale ice-sheet/shelf models for the prediction of future sea-level rise? A variety of broader impact work will be done both specifically targeting the research field area and more broadly addressing scientific and societal concerns. The field area contains a critical logistics roadway that connects McMurdo Station, Scott Base and a runway essential for continent-wide air logistics. The project will inform how to stabilize the roadway against excessive damage from summer ablation and other factors. Other broader impacts include: (a) Open-Science evaluation of climate systems engineering strategies for glacial geoengineering mitigation of sea-level rise, (b) cooperation with the Juneau Icefield Research Program (JIRP) education component, (c) support and facilitation of an online FieldSafe workshop and associated panel discussion to support early-career Antarctic field teams to mitigate environmental and interpersonal risks in remote field sites, and (d) potential involvement of an artist from the US Antarctic Program\u2019s Polar STEAM in the second field season.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": 175.0, "geometry": "POINT(168 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "ICE SHEETS; Ice Shelf Dynamics; McMurdo Sound", "locations": "McMurdo Sound", "north": -76.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "MacAyeal, Douglas; Banwell, Alison; Campbell, Seth; Schild, Kristin; Cassoto, Ryan", "platforms": null, "repositories": null, "science_programs": null, "south": -79.0, "title": "Collaborative Research: Ice-Shelf Rumpling and its Influence on Ice-Shelf Buttressing Processes.", "uid": "p0010478", "west": 161.0}, {"awards": "2317995 Herman, Rachael", "bounds_geometry": "POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.5,-55 -62,-55 -62.5,-55 -63,-55 -63.5,-55 -64,-55 -64.5,-55 -65,-55 -65.5,-55 -66,-56 -66,-57 -66,-58 -66,-59 -66,-60 -66,-61 -66,-62 -66,-63 -66,-64 -66,-65 -66,-65 -65.5,-65 -65,-65 -64.5,-65 -64,-65 -63.5,-65 -63,-65 -62.5,-65 -62,-65 -61.5,-65 -61))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 04 Oct 2024 00:00:00 GMT", "description": "Gentoo penguins (Pygoscelis papua) inhabit one of the fastest warming regions on Earth, the Western Antarctic Peninsula (WAP), where environmental shifts are measured in years, not decades. Despite this, the species is flourishing, growing in numbers and colonizing new habitats while sister species, such as Ad\u00e9lie penguins (P. adeliae), are declining in the region. This project will investigate to what extent epigenetics contributes to the success of gentoo penguins. Epigenetic variation is controlled by modifications to DNA or chromatin structure that affect the expression of genes, rather than changes to the underlying DNA sequence. This project will improve the understanding of gentoo penguin adaptation to climate change, and whether it is a result of increased flexibility in behavior and physiology driven by a greater capacity for epigenetic changes (i.e., epigenetic potential). The most studied form of epigenetic variation is the profiling of DNA methylation patterns. Environmental effects can trigger changes in DNA methylation that target specific tissues, allowing for localized gene expression shifts that result in modifications to the phenotype of an organism without any alteration to the underlying genotype. Given that epigenetic variation between populations often exceeds genetic variation, fine-scale genetic differentiation observed amongst gentoo penguin colonies suggests the possibility for local adaptation via even more divergent epigenetic changes and provides a framework for examining epigenetic variation across the gentoo penguin breeding range along multiple ecological axes. The researchers will test this by comprehensively characterizing the epigenomic profiles via patterns of DNA methylation in wild gentoo and Ad\u00e9lie penguins using cutting-edge high-resolution genomics techniques. Specifically, they will investigate whether gentoo penguins exhibit a greater degree of differences in DNA-methylation than underlying genetic differences, suggesting such epigenetic variation is driven by external environmental variables, potentially leading to improved capacity for local adaptation. This project will explore whether epigenetic potential may be selected for in individuals who disperse to new colony locations by comparing older, established colonies to new colonies at the range-edge. By implementing cutting-edge epigenetic methods in wild populations of gentoo penguins, this project will help address ecological questions on environmental plasticity that will impact conservation efforts and decisions on Marine Protected Areas (MPAs) on the Antarctic Peninsula.", "east": -55.0, "geometry": "POINT(-60 -63.5)", "instruments": null, "is_usap_dc": true, "keywords": "Gentoo Penguin; ECOLOGICAL DYNAMICS; Adaptation; Methylation; Antarctic Peninsula; Climate Change; Epigenetic Variation; PENGUINS", "locations": "Antarctic Peninsula", "north": -61.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Post Doc/Travel", "paleo_time": null, "persons": "Herman, Rachael", "platforms": null, "repositories": null, "science_programs": null, "south": -66.0, "title": "Postdoctoral Fellowship: OPP-PRF: Epigenetic Potential as a Driver of Local Adaptation in Gentoo Penguins (Pygoscelis Papua) along the Western Antarctic Peninsula", "uid": "p0010477", "west": -65.0}, {"awards": "2324998 Daane, Jacob; 1955368 Detrich, Harry", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 01 Aug 2024 00:00:00 GMT", "description": "Part I: Nontechnical description The ecologically important notothenioid fish of the Southern Ocean surrounding Antarctica will be studied to address questions central to polar, evolutionary, and adaptational biology. The rapid diversification of the notothenioids into \u003e120 species following a period of Antarctic glaciation and cooling of the Southern Ocean is thought to have been facilitated by key evolutionary innovations, including antifreeze glycoproteins to prevent freezing and bone reduction to increase buoyancy. In this project, a large dataset of genomic sequences will be used to evaluate the genetic mechanisms that underlie the broad pattern of novel trait evolution in these fish, including traits relevant to human diseases (e.g., bone density, renal function, and anemia). The team will develop new STEM-based research and teaching modules for undergraduate education at Northeastern University. The work will provide specific research training to scholars at all levels, including a post-doctoral researcher, a graduate student, undergraduate students, and high school students. The team will also contribute to public outreach, including, in part, the develop of teaching videos in molecular evolutionary biology and accompanying educational supplements. \u003cbr/\u003e\u003cbr/\u003e Part II: Technical description The researchers will leverage their comprehensive notothenioid phylogenomic dataset comprising \u003e250,000 protein-coding exons and conserved non-coding elements across 44 ingroup and 2 outgroup species to analyze the genetic origins of three iconic notothenioid traits: (1) loss of erythrocytes by the icefish clade in a cold, stable and highly-oxygenated marine environment. (2) reduction in bone mass and retention of juvenile skeletal characteristics as buoyancy mechanisms to facilitate foraging. And (3) loss of kidney glomeruli to retain energetically expensive antifreeze glycoproteins. The team will first track patterns of change in erythroid-related genes throughout the notothenioid phylogeny. They will then examine whether repetitive evolution of a pedomorphic skeleton in notothenioids is based on parallel or divergent evolution of genetic regulators of heterochrony. Third, they will determine whether there is mutational bias in the mechanisms of loss and re-emergence of kidney glomeruli. Finally, identified genetic mechanisms of evolutionary change will be validated by experimental testing using functional genomic strategies in the zebrafish model system.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "United States Of America; FISH", "locations": "United States Of America", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Daane, Jacob; Detrich, H. William", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "ANT LIA: Collaborative Research: Evolutionary Patterns and Mechanisms of Trait Diversification in the Antarctic Notothenioid Radiation", "uid": "p0010473", "west": -180.0}, {"awards": null, "bounds_geometry": null, "dataset_titles": "Deuterium isotopic composition of atmospheric methane across Dansgaard Oesgher Event 8, Talos Dome Ice Core, Antarctica", "datasets": [{"dataset_uid": "601814", "doi": null, "repository": "USAP-DC", "science_program": null, "title": "Deuterium isotopic composition of atmospheric methane across Dansgaard Oesgher Event 8, Talos Dome Ice Core, Antarctica", "url": "http://www.usap-dc.org/view/dataset/601814"}], "date_created": "Tue, 23 Jul 2024 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Abrupt Climate Change; Antarctica; Biogeochemical Cycles; Carbon Cycle; Cryosphere; Ice Core Records; Talos Dome", "locations": "Talos Dome; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Bauska, Thomas; Menking, James; Riddell-Young, Benjamin; Clark, Reid; Brook, Edward J.; Iseli, Rene; Lee, James; Schmitt, Jochen; Fischer, Hubertus", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "0087144 Conway, Howard", "bounds_geometry": "POLYGON((-150 -83.5,-148 -83.5,-146 -83.5,-144 -83.5,-142 -83.5,-140 -83.5,-138 -83.5,-136 -83.5,-134 -83.5,-132 -83.5,-130 -83.5,-130 -83.65,-130 -83.8,-130 -83.95,-130 -84.1,-130 -84.25,-130 -84.4,-130 -84.55,-130 -84.7,-130 -84.85,-130 -85,-132 -85,-134 -85,-136 -85,-138 -85,-140 -85,-142 -85,-144 -85,-146 -85,-148 -85,-150 -85,-150 -84.85,-150 -84.7,-150 -84.55,-150 -84.4,-150 -84.25,-150 -84.1,-150 -83.95,-150 -83.8,-150 -83.65,-150 -83.5))", "dataset_titles": "Impulse HF radar data from Conway Ridge", "datasets": [{"dataset_uid": "601810", "doi": null, "keywords": "Antarctica; Cryosphere; Siple Coast", "people": "Christianson, Knut; Hoffman, Andrew; Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Impulse HF radar data from Conway Ridge", "url": "https://www.usap-dc.org/view/dataset/601810"}], "date_created": "Mon, 22 Jul 2024 00:00:00 GMT", "description": "Marine ice sheets are low-pass filters of climate variability that take centuries to adjust to interior and near-terminus changes in mass balance. Constraining these century-scale changes from satellite observations that span only the last 40 years is challenging. Here, we take a different approach of carefully synthesizing different data sets to infer changes in the configurations of van der Veen and Mercer Ice Streams on the Siple Coast over the past 3000 years from englacial features encoded in ice-penetrating radar data. Englacial radar data from Conway Ridge reveal smooth, surface conformal layers overlying disrupted stratigraphy that suggest the van der Veen Ice Stream was 40 km wider over 3000 years ago. Englacial layer dating indicates that the ice stream narrowed to its present configuration between $\\sim3000$ and $\\sim1000$ years ago. Similarly disrupted stratigraphy and buried crevasses suggest that ice flowing from Mercer to Whillans Ice Stream across the northwestern tip of the ridge slowed shortly after. Using an ice-flow model capable of simulating shear margin migration, we evaluate whether small changes in ice thickness can lead to large changes in shear margin location. Our results suggest that the tip of Conway Ridge is sensitive to thinning and thickening, and that when the basal strength at the tip of the ridge increases with the height above flotation, the ice sheet shear margins can change quickly.", "east": -130.0, "geometry": "POINT(-140 -84.25)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIER ELEVATION/ICE SHEET ELEVATION; Siple Coast", "locations": "Siple Coast", "north": -83.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hoffman, Andrew; Conway, Howard", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Glacial History of Ridge AB, West Antarctica", "uid": "p0010470", "west": -150.0}, {"awards": "2209726 Lindzey, Laura", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "QIceRadar Antarctic Index of Radar Depth Sounding Data", "datasets": [{"dataset_uid": "200413", "doi": " 10.5281/zenodo.12123013", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "QIceRadar Antarctic Index of Radar Depth Sounding Data", "url": "https://zenodo.org/records/12123013"}], "date_created": "Wed, 19 Jun 2024 00:00:00 GMT", "description": "Ice penetrating radar is one of the primary tools that researchers use to study ice sheets and glaciers. With radar, it is possible to see a cross-section of the ice, revealing internal layers and the shape of the rocks under the ice. Among other things, this is important for calculating how much potential sea level change is locked up in the polar ice sheets, and how stable the ice sheets are likely to be in a warming world. This type of data is logistically challenging and expensive to collect. Historically, individual research groups have obtained funding to collect these data sets, and then the data largely stayed within that institution. There has been a recent push to make more and more data openly available, enabling the same datasets to be used by multiple research groups. However, it is still difficult to figure out what data is available because there is no centralized index. Additionally, each group releases data in a different format, which creates an additional hurdle to its use. This project addresses both of those challenges to data reuse by providing a unified tool for discovering where ice penetrating radar data already exists, then allowing the researcher to download and visualize the data. It is integrated into open-source mapping software that many in the research community already use, and makes it possible for non-experts to explore these datasets. This is particularly valuable for early-career researchers and for enabling interdisciplinary work. The US alone has spent many tens of millions of dollars on direct grants to enable the acquisition and analysis of polar ice penetrating radar data, and even more on the associated infrastructure and support costs. Unfortunately, much of these data is not publicly released, and even the data that has been released is not easily accessible. There is significant technical work involved in figuring out how to locate, download and view the data. This project is developing a tool that will both lower the barrier to entry for using this data and improve the workflows of existing users. Quantarctica and QGreenland have rapidly become indispensable tools for the polar research community, making diverse data sets readily available to researchers. However, ice penetrating radar is a major category of data that is not currently supported ? it is possible to see the locations of existing survey lines, and the ice thickness maps that have been interpreted from their data, but it is not readily possible to see the radargrams themselves in context with all of the other information. This capability is important because there is far more visual information contained in a radargram than simply its interpreted basal elevation or ice thickness. This project is developing software that will enable researchers to to view radargram images and interpreted surface and basal horizons in context with the existing map-view datasets in Quantarctica and QGreenland. A data layer shows the locations of all known ice penetrating radar surveys, color-coded based on availability. This layer enables data discovery and browsing. The plugin itself interacts with the data layer, first to download selected data, then to visualize the radargrams along with a cursor that moves simultaneously along the radargram and along the map view, making it straightforward to determine the precise geolocation of radar features.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "AIRCRAFT; GLACIERS/ICE SHEETS; Antarctica", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Polar Cyberinfrastructure", "paleo_time": null, "persons": "Lindzey, Laura", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e AIRCRAFT", "repo": "Zenodo", "repositories": "Zenodo", "science_programs": null, "south": -90.0, "title": "Elements: Making Ice Penetrating Radar More Accessible: A tool for finding, downloading and visualizing georeferenced radargrams within the QGIS ecosystem", "uid": "p0010464", "west": -180.0}, {"awards": null, "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 13 Jun 2024 00:00:00 GMT", "description": "The Amundsen Sea, near the fastest melting Antarctic glaciers, hosts one of the most productive polar ecosystems in the world. Phytoplankton serve as the base of the food chain, and their growth also removes carbon dioxide from the atmosphere. Phytoplankton growth is fertilized in this area by nutrient iron, which is only present at low concentrations in seawater. Prior studies have shown the seabed sediments may provide iron to the Amundsen Sea ecosystem. However, sediment sources of iron have never been studied here directly. This project fills this gap by analyzing sediments from the Amundsen Sea and investigating whether sediment iron fertilizes plankton growth. The results will help scientists understand the basic ecosystem drivers and predict the effects of climate change on this vibrant, vulnerable region. This project also emphasizes inclusivity and openness to the public. The researchers will establish a mentoring network for diverse polar scientists through the Polar Impact Network and communicate their results to the public through the website CryoConnect.org. \u003cbr/\u003e\u003cbr/\u003eThis project leverages samples already collected from the Amundsen Sea (NBP22-02) to investigate sediment iron (Fe) cycling and fluxes. The broad questions driving this research are 1) does benthic Fe fertilize Antarctic coastal primary productivity, and 2) what are the feedbacks between benthic Fe release and carbon cycling in the coastal Antarctic? To answer these questions, the researchers will analyze pore water Fe content and speciation and calculate fluxes of Fe across the sediment-water interface. These results will be compared to sediment characteristics (e.g., organic carbon content, reactive Fe content, proximity to glacial sources) to identify controls on benthic Fe release. This research dovetails with and expands on the science goals of the ?Accelerating Thwaites Ecosystem Impacts for the Southern Ocean? (ARTEMIS) project through which the field samples were collected. In turn, the findings of ARTEMIS regarding modeled and observed trace metal dynamics, surface water productivity, and carbon cycling will inform the conclusions of this project, allowing insight into the impact of benthic Fe in the whole system. This project represents a unique opportunity for combined study of the water column and sediment biogeochemistry which will be of great value to the marine biogeochemistry community and will inform future sediment-ocean studies in polar oceanography and beyond.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "SEDIMENT CHEMISTRY; TRACE ELEMENTS", "locations": null, "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": null, "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Benthic Iron Fluxes and Cycling in the Amundsen Sea", "uid": "p0010463", "west": null}, {"awards": "0958658 Bell, Robin; 1444690 Bell, Robin", "bounds_geometry": null, "dataset_titles": "Deep ICE (DICE) Radar Dataset from Ross Ice Shelf (ROSETTA-Ice); Shallow Ice Radar (SIR) Dataset from Ross Ice Shelf (ROSETTA-Ice)", "datasets": [{"dataset_uid": "601789", "doi": null, "keywords": "Airborne Radar; Antarctica; Cryosphere; Ice Thickness; Remote Sensing; Ross Ice Shelf", "people": "Wilner, Joel; Millstein, Joanna; Bertinato, Christopher; Dhakal, Tejendra; Frearson, Nicholas; Cordero, Isabel; Chu, Winnie; Bell, Robin; Spergel, Julian; Das, Indrani; Dong, LingLing", "repository": "USAP-DC", "science_program": null, "title": "Deep ICE (DICE) Radar Dataset from Ross Ice Shelf (ROSETTA-Ice)", "url": "https://www.usap-dc.org/view/dataset/601789"}, {"dataset_uid": "601794", "doi": null, "keywords": "Antarctica; Cryosphere; Remote Sensing; Ross Ice Shelf", "people": "Das, Indrani; Dong, LingLing; Packard, Sarah; Spergel, Julian; Wearing, Martin; Bell, Robin; Chu, Winnie; Cordero, Isabel; Frearson, Nicholas; Dhakal, Tejendra; Bertinato, Christopher; Keeshin, Skye", "repository": "USAP-DC", "science_program": null, "title": "Shallow Ice Radar (SIR) Dataset from Ross Ice Shelf (ROSETTA-Ice)", "url": "https://www.usap-dc.org/view/dataset/601794"}], "date_created": "Fri, 17 May 2024 00:00:00 GMT", "description": "The Lamont-Doherty Earth Observatory of Columbia University was awarded a multi-year grant (May 1, 2010- April 30, 2015) to develop an ice imaging system, or \"IcePod,\" for use in measuring the surface and subsurface topography of ice sheets. IcePod will enable research on the effects of global climate change on ice sheets and the effects of sub-glacial water on potential sea-level rise. IcePod sensors are contained in a Common Science Support Pod and operated on NYANG LC-130 aircraft during routine and targeted missions over Greenland and Antarctica. The IcePod instrument package consists of ice-penetrating radar, infrared and visible cameras, laser altimeter, inertial measurement unit, GPS receiver and data acquisition system. IcePod will also enable other instruments to be used in the modular Common Science Support Pod, and will become a shared community research facility providing data to the science community. Funding will support activities in both Greenland and Antarctica needed to commission IcePod, to develop a data reduction flow and data delivery system for IcePod data, and to engineer a UPS to provide IcePod with clean, reliable power for system operation. \u003cbr/\u003e\u003cbr/\u003eEvidence from satellites has documented that the amount of ice in both the earth\u0027s polar regions is decreasing as global temperatures increase. Understanding how this change is occurring and building an understanding of how fast these continent-sized pieces of ice will change in the future, is critical as society develops plans for adapting to changing coastlines. To measure change and understand the processes driving these changes requires the capacity to image the polat ice sheets and oceans from long-range aircraft. This award supplemented the original MRI-R2 program that developed innovative airborne imagery technology called IcePod. IcePod can be mounted on any LC-130, the aircraft used in the polar regions, for the major logistical support. The IcePod system was developed by engineers and scientists at Columbia University, working in close collaboration with the New York Air National Guard, who operate the ski-equipped LC-130 aircraft for the National Science Foundation in Antarctica and Greenland. The IcePod instrumentation package presently consists of: a scanning laser for precise measurements of the ice surface, visible and infrared imaging cameras to document the ice surface structure and temperature, ice-penetrating radar to recover the ice thickness and constrain the distribution of water at the ice sheet bed, and shallow-ice radar to measure snow accumulation. A magnetometer system is mounted inside the pod to recover information on the solid earth structure. Positioning of the IcePod during flights and the measurements are provided by precision GPS satellite data and inertial technology. A gravimeter, using its own rack, is also employed in conjunction with the IcePod sensor suite. The final commissioning of the system occurred in November - December 2014 in Antarctica as stipulated in the award. The IcePod was successfully operated in full polar conditions with a series of flights from McMurdo Station over the Ross Ice Shelf, the Ross Sea, the Dry Valleys, the Transantarctic Mountains and to South Pole. Protocol was also developed for data handling, robust data reduction, workflow and quality control and archiving of data. \u003cbr/\u003e\u003cbr/\u003eThe system is now available to the polar community for novel imaging applications.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Greenland; C-130; Remote Sensing; RADAR; GLACIERS/ICE SHEETS; Antarctica", "locations": "Antarctica; Greenland", "north": null, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences; Antarctic Instrumentation and Support; Antarctic Instrumentation and Support; Antarctic Earth Sciences; Antarctic Integrated System Science", "paleo_time": null, "persons": "Bell, Robin; Frearson, Nicholas; Zappa, Christopher; Studinger, Michael S.", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e C-130", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Development of an Ice Imaging System for Monitoring Changing Ice Sheets Mounted on the NYANG LC-130", "uid": "p0010462", "west": null}, {"awards": "2301026 Amsler, Charles", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 16 May 2024 00:00:00 GMT", "description": "General abstract\u003cbr/\u003e\u003cbr/\u003eMost organisms alternate between life stages that vary in the number and arrangement of their chromosomes, in the number of cells they possess, and in the environmental conditions in which they are best adapted to live. Much of what we understand about these alternations comes from organisms like animals and land plants in which one of the two stages dominates the life cycle with the other small and short-lived. However, across the tree of life there are countless examples of organisms in which both stages are of long duration, multicellular, or both. These life cycles challenge common ideas used to explain ecological and evolutionary patterns we see in nature. Macroalgae (seaweeds) display a wide range of life cycle types and consequently are excellent models to test and expand ideas about how life cycles evolve. Undersea forests of seaweeds with a variety of life cycle types dominate the shallow waters of the western Antarctic Peninsula where they are ecologically important and, for most of the species, at the southern end of their geographic range. Using existing samples from previous expeditions to Antarctica, the investigators are uniquely positioned to test and expand knowledge of life cycle evolution and how this intersects with reproductive mode variation. This project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the public. The project will support a postdoctoral scholar as well as a faculty member new to US Antarctic research. The investigators will take advantage of an existing program to include high school or undergraduate students in the work which will also expand mentorship experience for the postdoc. All team members will contribute by writing for blogs produced by professional societies for the public. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eTechnical abstract\u003cbr/\u003e\u003cbr/\u003eExisting macroalgal taxa samples from across a latitudinal gradient in the western Antarctic Peninsula will be used to explore patterns of genetic diversity from the center to the southern latitudinal limits of their range. Not only will genetic diversity be documented for an understudied and critical group of Antarctic organisms, but how it changes with latitude, compounded by high levels of endemism, will be explored. This will be accomplished by (i) characterization of latitudinal gradients in genetic diversity of many species and (ii) determination of the reproductive system of five focal foundation species. At present, there are few genetic data for macroalgae, dominant primary producers in coastal ecosystems around the world. This gap is particularly acute along Antarctic coastlines that are experiencing rapid climate change. Furthermore, Antarctica is isolated by the Southern Ocean, decreasing the likelihood of regular migration from other land masses. Latitudinal reproductive system patterns are predicted to be largely driven by recolonization events that increase with latitude due to changes in iceberg scour and sea ice coverage. Thus, Antarctica is the best place to understand what processes underlie reproductive mode variation in populations that are isolated, including many endemic taxa, while simultaneously extending our knowledge about how marginal environments converge with complex life cycles.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "MACROALGAE (SEAWEEDS); Antarctic Peninsula", "locations": "Antarctic Peninsula", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Amsler, Charles; Krueger-Hadfield, Stacy", "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Historical and Contemporary Drivers of Macroalgal Reproductive System Variation along the Western Antarctic Peninsula", "uid": "p0010460", "west": null}, {"awards": "2200448 Simms, Alexander", "bounds_geometry": null, "dataset_titles": "Constraining the Radiocarbon Reservoir Age for the Southern Ocean Using Whale Bones Salvaged from Early 20th Century Whaling Stations", "datasets": [{"dataset_uid": "601784", "doi": "10.15784/601784", "keywords": "Antarctica; C-14; Cryosphere; Radiocarbon Dates; Whale Bone; Whales", "people": "Sremba, Angela; Divola, Claire; Simms, Alexander; Baker, C. Scott; Friedlaender, Ari; Southon, John", "repository": "USAP-DC", "science_program": null, "title": "Constraining the Radiocarbon Reservoir Age for the Southern Ocean Using Whale Bones Salvaged from Early 20th Century Whaling Stations", "url": "https://www.usap-dc.org/view/dataset/601784"}], "date_created": "Thu, 09 May 2024 00:00:00 GMT", "description": "Radiocarbon dating is arguably the most common method for dating Quaternary deposits. However, accurate age assignments using radiocarbon dating are dependent on knowing the radiocarbon reservoir. For the coastal waters across Antarctica, the radiocarbon reservoirs show significant variation, ranging from 700 to 6,000 years depending on the material dated and the period in question. In this study, we examine the radiocarbon reservoir age for the shallow waters of the Southern Ocean using 23 whale bones salvaged from whaling stations operating on or near the Western Antarctic Peninsula between 1904 and 1916. The species origin of the bones had been identified previously as humpback, fin, or blue whales using sequences of mitochondrial (mt)DNA. We find an average reservoir age of 1050 +/- 135 years for these 23 whale bones, with a \u003c100 year difference in the reservoir age value by species. A comparison between our results and other studies through the Holocene suggest that the Southern Ocean surface water radiocarbon reservoir age has not significantly changed for the last 14,000 years. Combining our new ages with existing data sets provides insight to the stability of the Southern Ocean marine radiocarbon reservoir age, enhancing our understanding of ocean ventilation and upwelling dynamics throughout the Holocene.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "ORGANIC CARBON; West Antarctica", "locations": "West Antarctica", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Simms, Alexander", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "New constraints on 14C reservoirs around the Antarctic Peninsula and the Southern Ocean based on historically-harvested whale bones", "uid": "p0010457", "west": null}, {"awards": "2215771 Kreutz, Karl", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 01 Apr 2024 00:00:00 GMT", "description": "This award is for acquisition of new instrumentation to support acquisition of the new LA-HR-ICPMS instrumentation for the trace-element analysis of various environmental samples. This instrumentation will replace the original (and heavily used over two decades) ThermoScientific Element2 ICP-MS installed at the University of Maine?s Climate Change Institute (CCI). The new acquisition will significantly expand research capabilities of the CCI/ICP-MS Facility to improve the analysis of aqueous samples, supplemented with a laser ablation (LA) front end for ice, biological, and other solid materials. The current ICP-MS Facility was established in 2002 with an NSF/MRI award, which since then has served as a vital resource for climate, environmental, ecosystem, and engineering research and training at the U. Maine, across the state of Maine and beyond. The routine use and primary support of the Facility come from the Principal Investigators and their collaborators that group under three research areas: glaciochemistry and climate/environmental reconstruction; paleoceanography and marine biogeochemistry; and environmental sensor development and material science engineering. The U. Maine is the State?s Land \u0026 Sea Grant university and only PhD granting institution, so the campus is the de facto academic research and research training hub of the state of Maine. The proposed advances of this research \u0026 training instrumentation will immediately impact current and future NSF-funded research projects that support extensive national and international collaborations. Specific to this proposal are collaborations with the University of Venice (Italy) and the University of Cambridge/British Antarctic Survey to develop laser ablation ICP-MS imaging of ice cores, and collaborations with New Zealand, Swiss, Chinese, Canadian, and Brazilian colleagues to analyze ice, thereby maintaining our leadership role in global ice core and climate change research. Likewise, the enhanced carbonate analysis capacity of the Element XR will have an immediate impact on NSF-funded research projects in the Gulf of Maine and in the South Pacific. The proposed instrumentation will facilitate new and important collaborations between academic colleges (College of Natural Science, Forestry, and Agriculture and the College of Engineering) and research units - the CCI and the Frontier Institute for Research in Sensor Technology - across the campus, as well as enabling new and broader scientific collaborations with other academic and scientific institutions across Maine.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "OCEAN CHEMISTRY; GLACIERS/ICE SHEETS", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Instrumentation and Facilities", "paleo_time": null, "persons": "Kreutz, Karl; Mukhopadhyay, Sharmila M; Allen, Katherine A; Mayewski, Paul A.; Kurbatov, Andrei V.", "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "MRI: Acquisition of LA-HR-ICPMS instrumentation for climate, environmental, ecosystem, and engineering research at the University of Maine", "uid": "p0010456", "west": null}, {"awards": "2233187 Stammerjohn, Sharon", "bounds_geometry": "POLYGON((-180 -70,-177 -70,-174 -70,-171 -70,-168 -70,-165 -70,-162 -70,-159 -70,-156 -70,-153 -70,-150 -70,-150 -71,-150 -72,-150 -73,-150 -74,-150 -75,-150 -76,-150 -77,-150 -78,-150 -79,-150 -80,-153 -80,-156 -80,-159 -80,-162 -80,-165 -80,-168 -80,-171 -80,-174 -80,-177 -80,180 -80,178 -80,176 -80,174 -80,172 -80,170 -80,168 -80,166 -80,164 -80,162 -80,160 -80,160 -79,160 -78,160 -77,160 -76,160 -75,160 -74,160 -73,160 -72,160 -71,160 -70,162 -70,164 -70,166 -70,168 -70,170 -70,172 -70,174 -70,176 -70,178 -70,-180 -70))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 28 Feb 2024 00:00:00 GMT", "description": "The Ross Sea Region Marine Protected Area (RSRMPA), one of the world?s largest MPAs, encompasses one of the healthiest marine ecosystems remaining on this planet; however, it is exposed to increasing stress from ongoing climate change and fishing pressure. Numerous gaps in our understanding of the highly coupled nature of the Ross Sea marine ecosystem need to be addressed to support conservation efforts in the Ross Sea region, including informing the efficacy and management of the RSRMPA into the coming decades. The overarching goal of this research is to formulate an innovative and sustainable world-class research program aimed at better understanding, conserving, and managing the RSRMPA through the coordination of multi-faceted system-level approaches. There will be a coordinated effort to facilitate international collaboration; create education, outreach, and Diverse Equitable and Inclusive (DEI) opportunities; and increase conservation awareness. Coordinating Ross Sea marine ecosystem research will contribute to enhancing system-level global research, sustainable data networks, DEI, and climate equity. This program will also provide opportunity to develop similar frameworks for other large-scale, globally important systems. The trans-disciplinary aspiration can also serve to guide the NSF in sustaining or initiating new funding opportunities while addressing several of the 10 NSF BIG IDEAS and engaging multiple NSF Directorates. The project will help maintain NSF?s mission of scientific leadership by networking the Antarctic community by providing science-based conservation plans to help mitigate environmental changes in this pristine region of the Southern Ocean. The researchers will convene a workshop to strategize the implementation of an internationally networked, world class program that is based on inter- and trans-disciplinary approaches (including bridging science, cyberinfrastructure, policy, management, and conservation), while also providing opportunities for STEM education, early career development, and core DEI principles. To effectively facilitate the prioritization of research related to the regional and global interconnectedness of the Ross Sea marine ecosystem, the workshop will involve leading experts in Ross Sea marine research and other researchers, stakeholders, and policy experts involved in the greater oceanographic, climate and ecosystem/food web modeling communities. The workshop will determine a long-term decadal plan comprising the following phases: (1) initial data synthesis and ecosystem/food web model development; (2) field observations and modeling, networked through an internationally coordinated Ross Sea Observing System; and (3) data synthesis and modeling, including a ?sunset? plan to support ongoing RSRMPA management and preservation of the Ross Sea marine ecosystem. Outcomes will include a workshop report detailing the long-term research plan, a peer-reviewed article, educational and outreach materials, and a list of proposed research topics for implementing a world class research program and Principal Investigators who will help coordinate the multiple efforts aimed at addressing major gaps in our knowledge of the Ross Sea system.", "east": 160.0, "geometry": "POINT(-175 -75)", "instruments": null, "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; PELAGIC; COASTAL; United States Of America", "locations": "United States Of America", "north": -70.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Stammerjohn, Sharon; Brooks, Cassandra", "platforms": null, "repositories": null, "science_programs": null, "south": -80.0, "title": "Planning: Formulating and Sustaining a System-Level Understanding of a Large Marine Ecosystem in the Ross Sea Region Marine Protected Area to Better Conserve and Guide Policy", "uid": "p0010452", "west": -150.0}, {"awards": "1939146 Siddoway, Christine; 1939139 Scherer, Reed", "bounds_geometry": "POLYGON((-120 -66,-117.5 -66,-115 -66,-112.5 -66,-110 -66,-107.5 -66,-105 -66,-102.5 -66,-100 -66,-97.5 -66,-95 -66,-95 -67.1,-95 -68.2,-95 -69.3,-95 -70.4,-95 -71.5,-95 -72.6,-95 -73.7,-95 -74.8,-95 -75.9,-95 -77,-97.5 -77,-100 -77,-102.5 -77,-105 -77,-107.5 -77,-110 -77,-112.5 -77,-115 -77,-117.5 -77,-120 -77,-120 -75.9,-120 -74.8,-120 -73.7,-120 -72.6,-120 -71.5,-120 -70.4,-120 -69.3,-120 -68.2,-120 -67.1,-120 -66))", "dataset_titles": "Pliocene diatom abundance, IODP 379-U1532; Population morphometrics of the Southern Ocean diatom Fragilariopsis kerguelensis related to Sea Surface Temperature; U-Pb zircon and apatite fission track dates for IRD (ice-rafted cobbles and mineral grains) from IODP379 drill sites", "datasets": [{"dataset_uid": "601769", "doi": null, "keywords": "Antarctica; Biogenic Silica; Diatom", "people": "Furlong, Heather; Scherer, Reed Paul", "repository": "USAP-DC", "science_program": null, "title": "Pliocene diatom abundance, IODP 379-U1532", "url": "https://www.usap-dc.org/view/dataset/601769"}, {"dataset_uid": "601828", "doi": null, "keywords": "Amundsen Sea; Antarctica; Cryosphere; Geochronology; Marie Byrd Land; Subglacial Bedrock; Thermochronology", "people": "Siddoway, Christine", "repository": "USAP-DC", "science_program": null, "title": "U-Pb zircon and apatite fission track dates for IRD (ice-rafted cobbles and mineral grains) from IODP379 drill sites", "url": "https://www.usap-dc.org/view/dataset/601828"}, {"dataset_uid": "601804", "doi": "10.15784/601804", "keywords": "Amundsen Sea; Antarctica; Cryosphere; Oceanography; Sabrina Coast; Sea Surface Temperature; Southern Ocean", "people": "Ruggiero, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Population morphometrics of the Southern Ocean diatom Fragilariopsis kerguelensis related to Sea Surface Temperature", "url": "https://www.usap-dc.org/view/dataset/601804"}], "date_created": "Tue, 20 Feb 2024 00:00:00 GMT", "description": "Part I, Non-technical Abstract \u003cbr/\u003eConcerns that the West Antarctic Ice Sheet (WAIS) might be susceptible to releasing its ice as giant icebergs into the Southern Ocean due to a warming climate, raising global sea level, were first expressed more than 40 years ago. To best-assess this threat, scientists need to know whether such events occurred in the geologically recent past, during warm intervals of past glacial-interglacial cycles. Ocean drilling near the most vulnerable sector of the WAIS, in 2019, yielded seafloor geologic records demonstrating times when icebergs dropped large volumes of sands and pebbles, called ice-rafted detritus (IRD) in deep water of the Amundsen Sea. Occurring together with IRD that was eroded from bedrock beneath the ice sheets, there are abundant microfossils of diatoms (algal plankton), which indicate high biological productivity in the open ocean. The new sediment cores provide a complete, uninterrupted record of a time of dramatic fluctuations of ice sheet extent that occurred over the last 3 million years. Therefore, they provide the means to obtain clear answers to the question whether ice sheet collapse occurred in the past and offering clues to its potential future. This project will investigate sediment intervals where IRD coincides with evidence of high diatom production, to test whether these two criteria indicate rapid ice sheet collapse. Geochemical analysis of IRD pebbles will help trace the source of the icebergs to likely on-land sites. By analyzing conditions of high diatom and IRD accumulation in deep ocean sediment, where local coastal influences can be avoided, we will assess oceanographic and climatic conditions associated with past ice sheet collapse events. Diatoms provide powerful evidence of temperature and ocean productivity changes in the past, that, when linked to time, can translate into rates of ice sheet drawdown. These results will provide critical data for designing, constraining and testing the next suite computer models that can determine the likelihood and timing of future ice sheet collapse in a warming world. The project will include training of undergraduate and graduate students from diverse backgrounds, and the public will be introduced to Antarctic science and engaged through several different outreach efforts.\u003cbr/\u003e\u003cbr/\u003ePart 2, Technical Abstract\u003cbr/\u003e\u003cbr/\u003eNew drillcores from the Amundsen Sea, Antarctica (IODP Expedition 379) contain a continuous record of oceanographic changes and iceberg rafted debris (IRD) spanning the last 5 million years. This study aims to identify the signature of retreat/collapse of the West Antarctic Ice Sheet (WAIS) in these continental margin, deep-sea sediments by quantitatively analyzing, in detail, diatom and IRD records across glacial-interglacial lithostratigraphic transitions to establish the timing and frequency of Late Pliocene and Pleistocene WAIS collapse events. The investigators will secure age constraints and diagnostic observations of marine paleoenvironmental conditions for selected interglacial intervals of cores from sites U1532 and U1533, using high resolution micropaleontology of diatom assemblages coupled with microstratigraphic analysis of IRD depositional events, while petrography, geochronology and thermochronology of iceberg rafted clasts will provide evidence of iceberg sources and pathways. Depositional paleotemperatures will be assessed via a new paleotemperature proxy based on quantitative assessment of morphologic changes in the dominant Southern Ocean diatom Fragilariopsis kerguelensis. Their results will contribute to parameterization of new ice sheet models that seek to reconstruct and forecast West Antarctic Ice Sheet behavior. This project will directly contribute to undergraduate education at an undergraduate-only college and at a public university that serves a demographic typified by first generation university students and underrepresented groups. Spanning geology, geochemistry, sedimentology, paleontology and paleoceanography, the proposed work will allow undergraduate students to develop diverse skills through hands-on research within a collaborative team that is dedicated to societally relevant research. The two graduate students will conduct original research and work alongside/mentor undergraduates, making for a well-rounded research experience that prepares them for success in future academic or employment sectors. The discoveries that come from this deep-sea record from West Antarctica will be communicated by students and investigators at national and international conferences and an array of public science outreach events.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -95.0, "geometry": "POINT(-107.5 -71.5)", "instruments": null, "is_usap_dc": true, "keywords": "ICEBERGS; SEA SURFACE TEMPERATURE; Amundsen Sea; MICROFOSSILS", "locations": "Amundsen Sea", "north": -66.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY; PHANEROZOIC \u003e CENOZOIC \u003e NEOGENE \u003e PLIOCENE", "persons": "Scherer, Reed Paul; Siddoway, Christine", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.0, "title": "Collaborative Research: Testing the Linchpin of WAIS Collapse with Diatoms and IRD in Pleistocene and Late Pliocene Strata of the Resolution Drift, Amundsen Sea, Antarctica", "uid": "p0010451", "west": -120.0}, {"awards": "2023355 Schmandt, Brandon", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "A seismic catalog for the southernmost continent", "datasets": [{"dataset_uid": "601805", "doi": "10.15784/601805", "keywords": "Antarctica; Cryosphere; Earthquakes; Icequakes; Volcanic Events", "people": "Pena Castro, Andres", "repository": "USAP-DC", "science_program": null, "title": "A seismic catalog for the southernmost continent", "url": "https://www.usap-dc.org/view/dataset/601805"}], "date_created": "Tue, 20 Feb 2024 00:00:00 GMT", "description": "Part 1: Nontechnical\u003cbr/\u003e \u003cbr/\u003eUnlike other locations on the globe Antarctica is not known for having large earthquakes and the remote nature and harsh conditions make it difficult to install and maintain seismometers for earthquake detection. Some researchers believe the lack of large earthquakes is due to the continent being surrounded by inactive tectonic margins. However, in the last two decades, scientists have discovered that more earthquakes occur in the interior of the continent than previously observed. This suggests that there are many earthquakes missing from historic earthquake catalogs. This study aims to find the missing earthquakes using novel earthquake detection and location techniques from seismic data collected from temporary and permanent seismic stations in Antarctica over the last 25 years. Locating these earthquakes will help understand if and where earthquakes are located in Antarctica and will help in planning future seismic deployments. As part of the project broader impacts, a field expedition with the Girls on Rock program will be conducted to teach high school age girls, and especially those from underrepresented backgrounds, data visualization techniques using scientific data. \u003cbr/\u003e \u003cbr/\u003ePart 2: Technical\u003cbr/\u003e \u003cbr/\u003eThe spatial distribution of seismicity and the number of moderate magnitude earthquakes in Antarctica is not well-defined. The current catalog of earthquakes may be biased by uneven and sparse seismograph distribution on the continent. We will mine existing broadband seismic data from both permanent and temporary deployments to lower the earthquake detection threshold across Interior Antarctica, with a focus on tectonic earthquakes. The hypothesis is that Interior Antarctica has abundant moderate magnitude earthquakes, previously undetected. These earthquakes are likely collocated with major tectonic features such as the Transantarctic Mountains, the suspected Vostok collision zone, the West Antarctic Rift System, the crustal compositional boundary between East and West Antarctica, and the Cretaceous East Antarctic Rift. Previous seismic deployments have recorded earthquakes in the Antarctic interior, suggesting there are many earthquakes missing from the current catalog. We propose to use novel earthquake location techniques designed for automated detection and location using 25 years of continuous data archived at IRIS from PASSCAL experiments and permanent stations. The approach will use STA/LTA detectors on the first arrival P-wave to 90 degrees distance, Reverse Time Imaging to locate events, and beamforming at dense arrays strategically located on cratons for enhanced detection and location. The combination of detection and location techniques used in this work has not been used on teleseismic body waves, although similar methods have worked well for surface wave studies. If successful the project would provide an excellent training dataset for future scrutiny of newly discovered Antarctic seismicity with machine learning approaches and/or new targeted data collection. We plan to collaborate with Girls on Rock, a local and international organization committed to building a culturally diverse community in science, art, and wilderness exploration, in a summer field expedition and integrating computer coding into post-field scientific projects.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Seismic Events; Icequakes; TECTONICS; Earthquakes", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Polar Special Initiatives", "paleo_time": null, "persons": "Schmandt, Brandon", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "EAGER: Lowering the detection threshold of Antarctic seismicity to reveal undiscovered intraplate deformation", "uid": "p0010450", "west": -180.0}, {"awards": "1841467 MacAyeal, Douglas; 1841607 Banwell, Alison", "bounds_geometry": "POLYGON((-68.28 -71.1,-68.202 -71.1,-68.124 -71.1,-68.046 -71.1,-67.968 -71.1,-67.89 -71.1,-67.812 -71.1,-67.734 -71.1,-67.656 -71.1,-67.578 -71.1,-67.5 -71.1,-67.5 -71.14999999999999,-67.5 -71.19999999999999,-67.5 -71.25,-67.5 -71.3,-67.5 -71.35,-67.5 -71.39999999999999,-67.5 -71.44999999999999,-67.5 -71.5,-67.5 -71.55,-67.5 -71.6,-67.578 -71.6,-67.656 -71.6,-67.734 -71.6,-67.812 -71.6,-67.89 -71.6,-67.968 -71.6,-68.046 -71.6,-68.124 -71.6,-68.202 -71.6,-68.28 -71.6,-68.28 -71.55,-68.28 -71.5,-68.28 -71.44999999999999,-68.28 -71.39999999999999,-68.28 -71.35,-68.28 -71.3,-68.28 -71.25,-68.28 -71.19999999999999,-68.28 -71.14999999999999,-68.28 -71.1))", "dataset_titles": "Dataset for: Banwell et al. 2024, \u0027Observed meltwater-induced flexure and fracture at a doline on George VI Ice Shelf, Antarctica\u0027, Journal of Glaciology.", "datasets": [{"dataset_uid": "601771", "doi": "10.15784/601771", "keywords": "Antarctica; Antarctic Peninsula; AWS; Cryosphere; GNSS; GPS Data; Ice-Shelf Flexure; Ice Shelf Fracture; Ice-Shelf Melt; Timelaps Images", "people": "Dell, Rebecca; MacAyeal, Douglas; Banwell, Alison; Willis, Ian; Stevens, Laura", "repository": "USAP-DC", "science_program": null, "title": "Dataset for: Banwell et al. 2024, \u0027Observed meltwater-induced flexure and fracture at a doline on George VI Ice Shelf, Antarctica\u0027, Journal of Glaciology.", "url": "https://www.usap-dc.org/view/dataset/601771"}], "date_created": "Thu, 15 Feb 2024 00:00:00 GMT", "description": "The evolution of surface and shallow subsurface meltwater across Antarctic ice shelves has important implications for their (in)stability, as demonstrated by the 2002 rapid collapse of the Larsen B Ice Shelf. It is vital to understand the causes of ice-shelf (in)stability because ice shelves buttress against the discharge of inland ice and therefore influence ice-sheet contributions to sea-level rise. Ice-shelf break-up may be triggered by stress variations associated with surface meltwater movement, ponding, and drainage. These variations may cause an ice shelf to flex and fracture. This four-year project will provide key geophysical observations to improve understanding of ice-shelf meltwater and its effects on (in)stability. The work will be conducted on the George VI Ice Shelf on the Antarctic Peninsula, where hundreds of surface lakes form each summer. \u003cbr/\u003e\u003cbr/\u003eOver a 27-month period, global positioning systems, seismometers, water pressure transducers, automatic weather stations, and in-ice thermistor strings will be deployed to record ice shelf flexure, fracture seismicity, water depths, and surface and subsurface melting, respectively, in and around several surface lakes on the George VI Ice Shelf, within roughly 20 km of the British Antarctic Survey\u0027s Fossil Bluff Station. Field data will be used to validate and extend the team\u0027s approach to modelling ice-shelf flexure and stress, and possible \"Larsen-B style\" ice-shelf instability and break-up.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -67.5, "geometry": "POINT(-67.89 -71.35)", "instruments": null, "is_usap_dc": true, "keywords": "ICE SHEETS; Antarctica; ICE MOTION; Ice-Shelf Flexure; GPS Data", "locations": "Antarctica", "north": -71.1, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Banwell, Alison; Macayeal, Douglas", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -71.6, "title": "NSFGEO-NERC: Ice-shelf Instability Caused by Active Surface Meltwater Production, Movement, Ponding and Hydrofracture", "uid": "p0010449", "west": -68.28}, {"awards": "1744989 LaRue, Michelle", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Detecting climate signals in populations: case of emperor penguin; Emperor penguin population trends (2009-2018); Landfast ice: a major driver of reproductive success in a polar seabird", "datasets": [{"dataset_uid": "601513", "doi": "10.15784/601513", "keywords": "Antarctica; Breeding Success; Emperor Penguin; Fast Sea Ice", "people": "Labrousse, Sara; Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Landfast ice: a major driver of reproductive success in a polar seabird", "url": "https://www.usap-dc.org/view/dataset/601513"}, {"dataset_uid": "601491", "doi": "10.15784/601491", "keywords": "Antarctica", "people": "Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Detecting climate signals in populations: case of emperor penguin", "url": "https://www.usap-dc.org/view/dataset/601491"}, {"dataset_uid": "200410", "doi": "10.5061/dryad.m63xsj48v", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Emperor penguin population trends (2009-2018)", "url": "https://doi.org/10.5061/dryad.m63xsj48v"}], "date_created": "Thu, 08 Feb 2024 00:00:00 GMT", "description": "This project on emperor penguin populations will quantify penguin presence/absence, and colony size and trajectory, across the entire Antarctic continent using high-resolution satellite imagery. For a subset of the colonies, population estimates derived from high-resolution satellite images will be compared with those determined by aerial surveys - these results have been uploaded to MAPPPD (penguinmap.com) and are freely available for use. This validated information will be used to determine population estimates for all emperor penguin colonies through iterations of supervised classification and maximum likelihood calculations on the high-resolution imagery. The effect of spatial, geophysical, and environmental variables on population size and decadal-scale trends will be assessed using generalized linear models. This research will result in a first ever empirical result for emperor penguin population trends and habitat suitability, and will leverage currently-funded NSF infrastructure and hosting sites to publish results in near-real time to the public.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "COMMUNITY DYNAMICS; USA/NSF; Amd/Us; USAP-DC; Antarctica; AMD", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "LaRue, Michelle; Ito, Emi; Jenouvrier, Stephanie", "platforms": null, "repo": "USAP-DC", "repositories": "Dryad; USAP-DC", "science_programs": null, "south": -90.0, "title": "A Multi-scale Approach to Understanding Spatial and Population Variability in Emperor Penguins", "uid": "p0010447", "west": -180.0}, {"awards": "1443522 Wannamaker, Philip", "bounds_geometry": "POLYGON((166 -77.15,166.34 -77.15,166.68 -77.15,167.02 -77.15,167.36 -77.15,167.7 -77.15,168.04 -77.15,168.38 -77.15,168.72 -77.15,169.06 -77.15,169.4 -77.15,169.4 -77.22500000000001,169.4 -77.30000000000001,169.4 -77.375,169.4 -77.45,169.4 -77.525,169.4 -77.60000000000001,169.4 -77.67500000000001,169.4 -77.75,169.4 -77.825,169.4 -77.9,169.06 -77.9,168.72 -77.9,168.38 -77.9,168.04 -77.9,167.7 -77.9,167.36 -77.9,167.02 -77.9,166.68 -77.9,166.34 -77.9,166 -77.9,166 -77.825,166 -77.75,166 -77.67500000000001,166 -77.60000000000001,166 -77.525,166 -77.45,166 -77.375,166 -77.30000000000001,166 -77.22500000000001,166 -77.15))", "dataset_titles": "Erebus volcano/Ross Island Magnetotelluric (MT) data", "datasets": [{"dataset_uid": "601493", "doi": "10.15784/601493", "keywords": "Antarctica; Mantle Melting; Mount Erebus", "people": "Wannamaker, Philip; Hill, Graham", "repository": "USAP-DC", "science_program": null, "title": "Erebus volcano/Ross Island Magnetotelluric (MT) data", "url": "https://www.usap-dc.org/view/dataset/601493"}], "date_created": "Mon, 05 Feb 2024 00:00:00 GMT", "description": "General Description:\u003cbr/\u003eThis project is intended to reveal the magma source regions, staging areas, and eruptive pathways within the active volcano Mount Erebus. This volcano is an end-member type known as phonolitic, which refers to the lava composition, and is almost purely carbon-dioxide-bearing and occurs in continental rift settings. It is in contrast to the better known water-bearing volcanoes which occur at plate boundary settings (such as Mount St Helens or Mount Fuji). Phonolitic volcanic eruptions elsewhere such as Tamboro or Vesuvius have caused more than 50,000 eruption related fatalities. Phonolites are also associated with rare earth element deposits, giving them economic interest. To illuminate the inner workings of Mount Erebus, we will cover the volcano with a dense network of geophysical probes based on magnetotelluric (MT) measurements. MT makes use of naturally occurring electromagnetic (EM) waves generated mainly by the sun as sources to provide images of the electrical conductivity structure of the Earth\u0027s interior. Conductivity is sensitive to the presence of fluids and melts in the Earth and so is well suited to understanding volcanic processes. The project is a cooperative effort between scientists from the United States, New Zealand, Japan and Canada. It implements new technology developed by the lead investigator and associates that allows such measurements to be taken on snow-covered terrains. This has applicability for frozen environments generally, such as resource exploration in the Arctic. The project supports a new post-doctoral researcher, and leverages imaging and measurement methods developed through support by other agencies and interfaced with commercial platforms.\u003cbr/\u003e\u003cbr/\u003eTechnical Description:\u003cbr/\u003eThe investigators propose to test magmatic evolution models for Mount Erebus volcano, Antarctica, using the magnetotelluric (MT) method. The phonolite lava flow compositions on Mount Erebus are uncommon, but provide a window into the range of upper mantle source compositions and melt differentiation paths. Explosive phonolite eruptions have been known worldwide for devastating eruptions such as Tambora and Vesuvius, and commonly host rare earth element deposits. In the MT method, temporal variations in the Earth\u0027s natural electromagnetic (EM) field are used as source fields to probe the electrical resistivity structure in the depth range of 1 to 100 kilometers. This effort will consist of approximately 100 MT sites, with some concentration in the summit area. Field acquisition will take place over two field seasons. The main goals are to 1) confirm the existence and the geometry of the uppermost magma chamber thought to reside at 5-10 kilometer depths; 2) attempt to identify, in the deeper resistivity structure, the magma staging area near the crust-mantle boundary; 3) image the steep, crustal-scale, near-vertical conduit carrying magma from the mantle; 4) infer the physical and chemical state from geophysical properties of a CO2-dominated mafic shield volcano; and 5) constrain the relationships between structural and magmatic/ hydrothermal activity related to the Terror Rift. Tomographic imaging of the interior resistivity will be performed using a new inversion platform developed at Utah, based on the deformable edge finite element method, that is the best available for accommodating the steep topography of the study area. The project is an international cooperation between University of Utah, GNS Science Wellington New Zealand (G. Hill, Co-I), and Tokyo Institute of Technology Japan (Y. Ogawa, Co-I), plus participation by University of Alberta (M. Unsworth) and Missouri State University (K. Mickus). Instrument deployments will be made exclusively by helicopter. The project implements new technology that allows MT measurements to be taken on snow-covered terrains. The project supports a new post-doctoral researcher, and leverages imaging and measurement methods developed through support by other agencies and interfaced with commercial platforms.", "east": 169.4, "geometry": "POINT(167.7 -77.525)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS", "is_usap_dc": true, "keywords": "MAGNETIC FIELD; FIELD SURVEYS; Ross Island; Magnetotelluric; Mount Erebus", "locations": "Ross Island; Mount Erebus", "north": -77.15, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Wannamaker, Philip", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.9, "title": "Magma Sources, Residence and Pathways of Mount Erebus Phonolitic Volcano, Antarctica, from Magnetotelluric Resistivity Structure", "uid": "p0010444", "west": 166.0}, {"awards": "2224760 Gooseff, Michael", "bounds_geometry": "POINT(162.87 -77)", "dataset_titles": "EDI Data Portal: McMurdo Dry Valleys LTER", "datasets": [{"dataset_uid": "200379", "doi": "", "keywords": null, "people": null, "repository": "Environmental Data Initiative (EDI)", "science_program": null, "title": "EDI Data Portal: McMurdo Dry Valleys LTER", "url": "https://portal.edirepository.org/nis/browseServlet?searchValue=MCM"}], "date_created": "Tue, 14 Nov 2023 00:00:00 GMT", "description": "In this iteration of the McMurdo LTER project (MCM6), the project team will test ecological connectivity and stability theory in a system subject to strong physical drivers (geological legacies, extreme seasonality, and contemporary climate change) and driven by microbial organisms. Since microorganisms regulate most of the world\u0027s critical biogeochemical functions, these insights will be relevant far beyond polar ecosystems and will inform understanding and expectations of how natural and managed ecosystems respond to ongoing anthropogenic global change. MCM6 builds on previous foundational research, both in Antarctica and within the LTER network, to consider the temporal aspects of connectivity and how it relates to ecosystem stability. The project will examine how changes in the temporal variability of ecological connectivity interact with the legacies of the existing landscape that have defined habitats and biogeochemical cycling for millennia. The project team hypothesizes that the structure and functioning of the MDV ecosystem is dependent upon legacies and the contemporary frequency, duration, and magnitude of ecological connectivity. This hypothesis will be tested with new and continuing monitoring, experiments, and analyses of long-term datasets to examine: 1) the stability of these ecosystems as reflected by sentinel taxa, 2) the relationship between ecological legacies and ecosystem resilience, 3) the importance of material carryover during periods of low connectivity to maintaining biological activity and community stability, and 4) how changes in disturbance dynamics disrupt ecological cycles through the polar night. Tests of these hypotheses will occur in field and modeling activities using new and long-term datasets already collected. New datasets resulting from field activities will be made freely available via widely-known online databases (MCM LTER and EDI). The project team has also developed six Antarctic Core Ideas that encompass themes from data literacy to polar food webs and form a consistent thread across the education and outreach activities. Building on past success, collaborations will be established with teachers and artists embedded within the science teams, who will work to develop educational modules with science content informed by direct experience and artistic expression. Undergraduate mentoring efforts will incorporate computational methods through a new data-intensive scientific training program for MCM REU students. The project will also establish an Antarctic Research Experience for Community College Students at CU Boulder, to provide an immersive educational and research experience for students from diverse backgrounds in community colleges. MCM LTER will continue its mission of training and mentoring students, postdocs, and early career scientists as the next generation of leaders in polar ecosystem science and stewardship. Historically underrepresented participation will be expanded at each level of the project. To aid in these efforts, the project has established Education \u0026 Outreach and Diversity, Equity, and Inclusion committees to lead, coordinate, support, and integrate these activities through all aspects of MCM6.", "east": 162.87, "geometry": "POINT(162.87 -77)", "instruments": null, "is_usap_dc": true, "keywords": "COMMUNITY DYNAMICS; ABLATION ZONES/ACCUMULATION ZONES; SOIL TEMPERATURE; DIATOMS; FIELD INVESTIGATION; PERMANENT LAND SITES; BUOYS; GROUND-BASED OBSERVATIONS; SEDIMENTS; SNOW WATER EQUIVALENT; SPECIES/POPULATION INTERACTIONS; WATER-BASED PLATFORMS; FIXED OBSERVATION STATIONS; VIRUSES; PHYTOPLANKTON; ACTIVE LAYER; FIELD SURVEYS; RADIO TRANSMITTERS; DATA COLLECTIONS; ECOLOGICAL DYNAMICS; LANDSCAPE; GROUND WATER; SNOW/ICE CHEMISTRY; LAND-BASED PLATFORMS; ANIMALS/INVERTEBRATES; ECOSYSTEM FUNCTIONS; HUMIDITY; GEOCHEMISTRY; SURFACE WINDS; RIVERS/STREAM; GLACIER MASS BALANCE/ICE SHEET MASS BALANCE; SNOW; LAND RECORDS; ATMOSPHERIC PRESSURE; SURFACE TEMPERATURE; ATMOSPHERIC RADIATION; BACTERIA/ARCHAEA; AIR TEMPERATURE; GLACIERS; SNOW/ICE TEMPERATURE; SOIL CHEMISTRY; METEOROLOGICAL STATIONS; WATER QUALITY/WATER CHEMISTRY; TERRESTRIAL ECOSYSTEMS; MOORED; PROTISTS; STREAMFLOW STATION; Dry Valleys; LAKE/POND; LAKE ICE; SNOW DEPTH; AQUATIC ECOSYSTEMS; SNOW DENSITY; FIELD SITES", "locations": "Dry Valleys", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Gooseff, Michael N.; Adams, Byron; Barrett, John; Diaz, Melisa A.; Doran, Peter; Dugan, Hilary A.; Mackey, Tyler; Morgan-Kiss, Rachael; Salvatore, Mark; Takacs-Vesbach, Cristina; Zeglin, Lydia H.", "platforms": "LAND-BASED PLATFORMS; LAND-BASED PLATFORMS \u003e FIELD SITES; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e DATA COLLECTIONS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e RADIO TRANSMITTERS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e FIXED OBSERVATION STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e METEOROLOGICAL STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e STREAMFLOW STATION; WATER-BASED PLATFORMS; WATER-BASED PLATFORMS \u003e BUOYS; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED \u003e BUOYS", "repo": "Environmental Data Initiative (EDI)", "repositories": "Environmental Data Initiative (EDI)", "science_programs": "LTER", "south": -77.0, "title": "LTER: MCM6 - The Roles of Legacy and Ecological Connectivity in a Polar Desert Ecosystem", "uid": "p0010440", "west": 162.87}, {"awards": "0943952 Cassano, John; 0944018 Lazzara, Matthew", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic Automatic Weather Stations", "datasets": [{"dataset_uid": "200375", "doi": "https://doi.org/10.48567/1hn2-nw60", "keywords": null, "people": null, "repository": "Antarctic Meteorological Research and Data Center", "science_program": null, "title": "Antarctic Automatic Weather Stations", "url": "https://amrdcdata.ssec.wisc.edu/dataset?q=0944018+"}], "date_created": "Fri, 20 Oct 2023 00:00:00 GMT", "description": "The Antarctic Automatic Weather Station (AWS) network, first commenced in 1978, is the most extensive meteorological observing system on the Antarctic continent, approaching its 30th year at many of its key sites. Its prime focus as a long term observational record is vital to the measurement of the near surface climatology of the Antarctic atmosphere. AWS units measure air-temperature, pressure, wind speed and direction at a nominal surface height of 3m. Other parameters such as relative humidity and snow accumulation may also be taken. Observational data from the AWS are collected via the DCS Argos system aboard either NOAA or MetOp polar orbiting satellites and thus made available globally, in near real time via the GTS (Global Telecommunications System), to operational and synoptic weather forecasters. The surface observations from the AWS network also are often used to check on satellite and remote sensing observations, and the simulations of Global Climate Models (GCMs). Research instances of its use in this project include continued development of the climatology of the Antarctic atmosphere and surface wind studies of the Ross Ice Shelf. The AWS observations benefit the broader earth system science community, supporting research activities ranging from paleoclimate studies to penguin phenology.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; DATA COLLECTIONS; SURFACE PRESSURE; HUMIDITY; AIR TEMPERATURE; FIELD SITES; LAND-BASED PLATFORMS; SURFACE WINDS; WEATHER STATIONS", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Lazzara, Matthew; Cassano, John", "platforms": "LAND-BASED PLATFORMS; LAND-BASED PLATFORMS \u003e FIELD SITES; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e DATA COLLECTIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e WEATHER STATIONS", "repo": "Antarctic Meteorological Research and Data Center", "repositories": "Antarctic Meteorological Research and Data Center", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Antarctic Automatic Weather Station Program", "uid": "p0010438", "west": -180.0}, {"awards": "2301363 Kurth, Andrew; 2301362 Lazzara, Matthew", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "AMRC Automatic Weather Station project data, 1980 - present (ongoing).", "datasets": [{"dataset_uid": "200414", "doi": "10.48567/1hn2-nw60", "keywords": null, "people": null, "repository": "Antarctic Meteorological Research and Data Center", "science_program": null, "title": "AMRC Automatic Weather Station project data, 1980 - present (ongoing).", "url": "https://amrdcdata.ssec.wisc.edu/group/about/automatic-weather-station-project"}], "date_created": "Fri, 20 Oct 2023 00:00:00 GMT", "description": "The Antarctic Automatic Weather Station (AWS) program is a long-term automated surface weather observing network measuring key standard meteorological parameters, including temperature, humidity, wind speed and direction, barometric pressure, solar radiation, and snow accumulation. Observations from the network support weather forecasting, science research, and educational activities, and all data collected are made available to the public. This project will continue to maintain and operate the existing network. These data provide some of the only available weather observations in this very remote portion of the Earth. To ensure fidelity, observations are reviewed and checked for errors by a combination of automated methods and expert review, enabling the data to be used in a wide range of research areas. The project will be overseen by a team of scientists, researchers, and students, and a newly created AWS Advisory Board will provide independent input and guidance.\r\n\r\nThe activities for this project will be focused on the continued operation of the AWS network, establishment of an AWS Advisory Board, student engagement and outreach activities. This project will continue to maintain the AWS systems while upgrading the real-time processing of meteorological data from the AWS network. The team will continue to adapt to changes communication methods to ensure that data is distributed widely and in a timely manner. Prior NSF investments in the Polar Climate and Weather Station (PCWS) are leveraged to develop a robust production version that can be reliably used year-round in Antarctica. AWS observations will be quality-controlled and placed into a database where the public will be able to search and select subsets of observations. To resolve conflicting radiation shield setups for temperature observations, the team plans to test different radiation shields (with and without aspiration) deployed for one year at South Pole Station. The project will be advised by an independent group of diverse peers through a newly developed AWS Advisory Board. The team will incorporate students from all levels in all aspects of the project, including in the research design, engineering and productions of the PCWS, and in field deployments. A concerted effort to engage the public will be undertaken via scaled-up interactions with television meteorologists from several states across the US to bring Antarctica to the public.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "AIR TEMPERATURE; HUMIDITY; SURFACE WINDS; INCOMING SOLAR RADIATION; Antarctica; SURFACE PRESSURE", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Lazzara, Matthew; Welhouse, Lee J; Mikolajczyk, David", "platforms": null, "repo": "Antarctic Meteorological Research and Data Center", "repositories": "Antarctic Meteorological Research and Data Center", "science_programs": null, "south": -90.0, "title": "Collaborative Research: The Automatic Weather Station Program: Antarctic Meteorological Sentinel Service 2024-2027", "uid": "p0010439", "west": -180.0}, {"awards": "2035078 Giometto, Marco; 2034874 Salesky, Scott", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 08 Sep 2023 00:00:00 GMT", "description": "1. A non-technical explanation of the project\u0027s broader significance and importance, that serves as a public justification for NSF funding. This part should be understandable to an educated reader who is not a scientist or engineer.\r\n\r\nKatabatic or drainage winds, carry high-density air from a higher elevation down a slope under the force of gravity. Although katabatic flows are ubiquitous in alpine and polar regions, a surface-layer similarity theory is currently lacking for these flows, undermining the accuracy of numerical weather and climate prediction models. This project is interdisciplinary, and will give graduate and undergraduate students valuable experience interacting with researchers outside their core discipline. Furthermore, this project will broaden participating in science through recruitment of students from under-represented groups at OU and CU through established programs.\r\n\r\nThe Antarctic Ice Sheet drives many processes in the Earth system through its modulation of regional and global atmospheric and oceanic circulations, storage of fresh water, and effects on global albedo and climate. An understanding of the surface mass balance of the ice sheets is critical for predicting future sea level rise and for interpreting ice core records. Yet, the evolution of the ice sheets through snow deposition, erosion, and transport in katabatic winds (which are persistent across much of the Antarctic) remains poorly understood due to the lack of an overarching theoretical framework, scarcity of in situ observational datasets, and a lack of accurate numerical modeling tools. Advances in the fundamental understanding and modeling capabilities of katabatic transport processes are urgently needed in view of the future climatic and snowfall changes that are projected to occur within the Antarctic continent. This project will leverage the expertise of a multidisciplinary team of investigators (with backgrounds spanning cryospheric science, environmental fluid mechanics, and atmospheric science) to address these knowledge gaps.\r\n\r\n\r\n2. A technical description of the project that states the problem to be studied, the goals and scope of the research, and the methods and approaches to be used. In many cases, the technical project description may be a modified version of the project summary submitted with the proposal. \r\n\r\nUsing field observations and direct numerical simulations of katabatic flow, this project is expected--- for the first time---to lead to a surface-layer similarity theory for katabatic flows relating turbulent fluxes to mean vertical gradients. The similarity theory will be used to develop surface boundary conditions for large eddy simulations (LES), enabling the first accurate LES of katabatic flow.\r\n\r\nThe numerical tools that the PIs will develop will allow them to investigate how the partitioning between snow redistribution, transport, and sublimation depends on the environmental parameters typically encountered in Antarctica (e.g. atmospheric stratification, surface sloping angles, and humidity profiles), and to develop simple models to infer snow transport based on satellite remote sensing and regional climate models\r\n\r\nThis award reflects the NSF statutory mission and has been deemed worthy of support through evaluation using the intellectual merit of the Foundation and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "TURBULENCE; ATMOSPHERIC RADIATION; DATA COLLECTIONS; SNOW/ICE; SNOW; FIELD INVESTIGATION; AIR TEMPERATURE; HUMIDITY", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Salesky, Scott; Giometto, Marco; Das, Indrani", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e DATA COLLECTIONS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Snow Transport in Katabatic Winds and Implications for the Antarctic Surface Mass Balance: Observations, Theory, and Numerical Modeling", "uid": "p0010433", "west": null}, {"awards": "2231559 Tinto, Kirsteen; 2231558 Smith, Nathan", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 01 Sep 2023 00:00:00 GMT", "description": "PUBLIC ABSTRACT \u2013 NSF 2231558/2231559\r\nCOLLABORATIVE RESEARCH: CONFERENCE: INTERDISCIPLINARY ANTARCTIC EARTH SCIENCE CONFERENCE \u0026 DEEP-FIELD PLANNING WORKSHOP\r\n\r\nThe unique Antarctic environment offers insight into processes and records not seen anywhere else on Earth, and is critical to understanding our planet\u2019s history and future. The remoteness and logistics of Antarctic science brings together researchers from diverse disciplines who otherwise wouldn\u2019t be presented with opportunities for collaboration, and often rarely attend the same academic conferences. The Interdisciplinary Antarctic Earth Science (IAES) conference is a biennial gathering that supports the collaboration of U.S. bio-, cryo-, geo-, and atmospheric science researchers working in the Antarctic. This proposal will support the next two IAES conferences to be held in 2022 and 2024, as well as a paired deep-field camp planning workshop. The IAES conference is important to the mission of the NSF in supporting interdisciplinary collaboration in the Antarctic earth sciences, but also fulfills recommendations by the National Academy for improving awareness, data sharing, and early career researcher mentoring and development. The size and scope of the IAES conference allow it to serve as a hub for novel, interdisciplinary collaboration, as well as an incubator for the development of the next generation of Antarctic earth scientists.\r\n\r\nThe goals of the IAES conference are to develop and deepen scientific collaborations across the Antarctic earth science community, and create a framework for future deep-field, as well as non-field-based research. The conference will share science through presentations of current research and keynote talks, broaden participation through welcoming new researchers from under-represented communities and disciplines, and deepen collaboration through interdisciplinary networking highlighting potential research connections, novel mentorship activities, and promoting data re-use, and application of remote sensing and modeling. Discussions resulting from the IAES conference will be used to develop white papers on future Antarctic collaborative research and deep-field camps based on community-driven research priorities. Community surveys and feedback will be solicited throughout the project to guide the future development of the IAES conference.\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "GEOMORPHIC LANDFORMS/PROCESSES; GEOCHEMISTRY; California; ICE CORE RECORDS; ECOLOGICAL DYNAMICS; GLACIERS/ICE SHEETS; PALEOCLIMATE RECONSTRUCTIONS", "locations": "California", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Smith, Nathan; Tinto, Kirsty", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Conference: Interdisciplinary Antarctic Earth Science Conference \u0026 Deep-Field Planning Workshop", "uid": "p0010432", "west": -180.0}, {"awards": "2317263 Cross, Andrew", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 14 Aug 2023 00:00:00 GMT", "description": "The seaward motion of ice sheets and glaciers is primarily controlled by basal sliding below, and internal viscous flow within, ice masses. The latter of these\u2014viscous flow\u2014is dependent on various factors, including temperature, stress, grain size, and the alignment of ice crystals during flow to produce a crystal orientation fabric (COF). Historically, ice flow has been modeled using a constitutive equation, termed \u201cGlen\u2019s law\u201d, that describes ice flow rate as a function of temperature and stress. Glen\u2019s law was constrained under relatively high-stress conditions, and is often attributed to the motion of crystal defects within ice grains. More recently, however, grain boundary sliding (GBS) has been invoked as the rate-controlling process under low-stress, \u201csuperplastic\u201d conditions. The grain boundary sliding hypothesis is contentious because GBS is not thought to produce a COF, whereas geophysical measurements and polar ice cores demonstrate strong COFs in polar ice masses. However, very few COF measurements have been conducted on ice samples subjected to superplastic flow conditions in the laboratory. In this project, the PI primarily seeks to measure the evolution of ice COF across the transition from superplastic to Glen-type creep. Results will be used to interrogate the role of superplastic GBS creep within polar ice masses, and thereby provide constraints on polar ice discharge models.\r\n\r\nPolycrystalline ice samples with grain sizes ranging from 5 \u00b5m to 1000 \u00b5m will be fabricated and deformed in the PI\u2019s laboratory at WHOI, using a 1-atm cryogenic axial-torsion apparatus. Experiments will be conducted at temperatures of \u221230\u00b0C to \u221210\u00b0C, and at a constant uniaxial strain rate of 10-7 s-1. Under these conditions, 5% to 99.99% of strain should be accommodated by superplastic, GBS-limited creep, depending on the sample grain size. The deformed samples will then be imaged using cryogenic electron backscatter diffraction (cryo-EBSD) and high-angular-resolution electron backscatter diffraction (HR-EBSD) to quantify COF, grain size, grain shape, and crystal defect (dislocation) densities, among other microstructural properties. These measurements will be used to decipher the rate-controlling mechanisms operating within different thermomechanical regimes, and resolve a long-standing debate over whether superplastic creep can produce a COF in ice. In addition to the polycrystal experiments, ice bicrystals will be fabricated and deformed to investigate the micromechanical behavior of individual grain boundaries under superplastic conditions. Ultimately, these results will be used to provide a microstructural toolbox for identifying superplastic creep using geophysical (e.g., seismic, radar) and glaciological (e.g., ice core) observations. This project will support one graduate student within the MIT-WHOI Joint Program, one or more undergraduate summer students, and a junior faculty member (the PI). In addition, the PI will host a workshop aimed at bringing together experimentalists, glaciologists, and ice modelers to facilitate cross-disciplinary knowledge sharing and collaborative problem solving.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "United States Of America; Rheology; ROCKS/MINERALS/CRYSTALS; GLACIERS/ICE SHEETS", "locations": "United States Of America", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Cross, Andrew", "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Microstructural Evolution during Superplastic Ice Creep", "uid": "p0010430", "west": null}, {"awards": "2142491 Young, Jodi", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 26 Jul 2023 00:00:00 GMT", "description": "The aims of this CAREER proposal are to gain a greater understanding of the role of sympagic algae in Antarctic marine ecosystems with the goal to better parameterize their role in biogeochemical and ecosystem processes across dynamic environments. Specifically, this proposal will apply a laboratory-scale, ice-tank system that recreates the seasonal cycle of sea ice in the laboratory for the purpose of studying sympagic microbes to study the following questions:\r\n1.1 \tStarting with a late autumn, mixed phytoplankton community, how do different algal species specialize to sea ice, seawater and flooded snow/ice habitats over winter?\r\n1.2 \tWhat are the relationships between different methods of measuring primary production (fluorescence, O2 production, CO2 drawdown) in sea ice? Does this differ from seawater?\r\n1.3 \tDoes the presence of sea-ice algae influence the physical structure of sea ice?\r\n1.4\tHow does the release of compatible solutes from algae during ice melt influence the dissolved organic pool?\r\nIn addition, I propose to integrate educational activities with my research goals. This includes development of an educational program at the university and K-12 level on Antarctic Sciences that develops critical thinking and quantitative skills, encourages STEM participation from underrepresented groups and establishes an interactive network of Antarctic researchers to broaden research opportunities.\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "MARINE ECOSYSTEMS", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Young, Jodi", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "CAREER: Experimentally Testing the Role of Sympagic Algae in Sea-ice Environments using a Laboratory Scale Ice-tank.", "uid": "p0010425", "west": -180.0}, {"awards": "2302832 Reilly, Brendan", "bounds_geometry": "POLYGON((-70 -55,-67 -55,-64 -55,-61 -55,-58 -55,-55 -55,-52 -55,-49 -55,-46 -55,-43 -55,-40 -55,-40 -56.1,-40 -57.2,-40 -58.3,-40 -59.4,-40 -60.5,-40 -61.6,-40 -62.7,-40 -63.8,-40 -64.9,-40 -66,-43 -66,-46 -66,-49 -66,-52 -66,-55 -66,-58 -66,-61 -66,-64 -66,-67 -66,-70 -66,-70 -64.9,-70 -63.8,-70 -62.7,-70 -61.6,-70 -60.5,-70 -59.4,-70 -58.3,-70 -57.2,-70 -56.1,-70 -55))", "dataset_titles": "NRM, ARM, IRM, and magnetic susceptibility investigations on U1537 and U1538 cube samples; Rock magnetic data from IODP Exp. 382 Sites U1537 and U1538 to support Reilly et al. \"A geochemical mechanism for \u003e10 m offsets of magnetic reversals inferred from the comparison of two Scotia Sea drill sites\"", "datasets": [{"dataset_uid": "200411", "doi": "10.5281/zenodo.10035106", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Rock magnetic data from IODP Exp. 382 Sites U1537 and U1538 to support Reilly et al. \"A geochemical mechanism for \u003e10 m offsets of magnetic reversals inferred from the comparison of two Scotia Sea drill sites\"", "url": "https://zenodo.org/records/10035107"}, {"dataset_uid": "200412", "doi": "10.7288/V4/MAGIC/19778", "keywords": null, "people": null, "repository": "MagIC (EarthRef)", "science_program": null, "title": "NRM, ARM, IRM, and magnetic susceptibility investigations on U1537 and U1538 cube samples", "url": "http://dx.doi.org/10.7288/V4/MAGIC/19778"}], "date_created": "Wed, 12 Jul 2023 00:00:00 GMT", "description": "The potential for future sea level rise from melting and collapse of Antarctic ice sheets and glaciers is concerning. We can improve our understanding of how water is exchanged between Antarctic ice sheets and the ocean by studying how ice sheets behaved in past climates, especially conditions that were similar to or warmer than those at present. For this project, the research team will document Antarctica\u0027s response across an interval when Earth transitioned from the warm Pliocene into the Pleistocene ice ages by combining marine and land evidence for glacier variations from sites near the Antarctic Peninsula, complimented by detailed work on timescales and fossil evidence for environmental change. An important goal is to test whether Antarctica\u0027s glaciers changed at the same time as glaciers in the Northern Hemisphere as Earth\u0027s most recent Ice Age intensified, or alternatively responded to regional climate forcing in the Southern Hemisphere. Eleven investigators from seven US institutions, as well as Argentine collaborators, will study new sediment cores from the International Ocean Discovery Program, as well as legacy cores from that program and on-land outcrops on James Ross Island. The group embraces a vertically integrated research program that allows high school, undergraduate, graduate, post-docs and faculty to work together on the same projects. This structure leverages the benefits of near-peer mentoring and the development of a robust collaborative research network while allowing all participants to take ownership of different parts of the project. All members of the team are firmly committed to attracting researchers from under-represented groups and will do this through existing channels as well as via co-creating programming that centers the perspectives of diverse students in conversations about sea-level rise and climate change.\r\n\r\nThe proposed research seeks to understand phasing between Northern and Southern Hemisphere glacier and climate changes, as a means to understand drivers and teleconnections. The dynamics of past Antarctic glaciation can be studied using the unique isotope geochemical and mineralogic fingerprints from glacial sectors tied to a well-constrained time model for the stratigraphic successions. The proposed work would further refine the stratigraphic context through coupled biostratigraphic and magnetostratigraphic work. The magnitude of iceberg calving and paths of icebergs will be revealed using the flux, geochemical and mineralogic signatures, and 40Ar/39Ar and U-Pb geochronology of ice-rafted detritus. These provenance tracers will establish which sectors of Antarctica\u0027s ice sheets are more vulnerable to collapse, and the timing and pacing of these events will be revealed by their stratigraphic context. Additionally, the team will work with Argentine collaborators to connect the marine and terrestrial records by studying glacier records intercalated with volcanic flows on James Ross Island. These new constraints will be integrated with a state of the art ice-sheet model to link changes in ice dynamics with their underlying causes. Together, these tight stratigraphic constraints, geochemical signatures, and ice-sheet model simulations will provide a means to compare to the global records of climate change, understand their primary drivers, and elucidate the role of the Antarctic ice sheet in a major, global climatic shift from the Pliocene into the Pleistocene.", "east": -40.0, "geometry": "POINT(-55 -60.5)", "instruments": null, "is_usap_dc": true, "keywords": "PALEOMAGNETISM; SEDIMENTS; Scotia Sea", "locations": "Scotia Sea", "north": -55.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e NEOGENE \u003e PLIOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e NEOGENE; PHANEROZOIC \u003e CENOZOIC", "persons": "Reilly, Brendan", "platforms": null, "repo": "Zenodo", "repositories": "MagIC (EarthRef); Zenodo", "science_programs": null, "south": -66.0, "title": "Collaborative Research: Linking Marine and Terrestrial Sedimentary Evidence for Plio-pleistocene Variability of Weddell Embayment and Antarctic Peninsula Glaciation", "uid": "p0010424", "west": -70.0}, {"awards": "1847173 Duddu, Ravindra", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 07 Jul 2023 00:00:00 GMT", "description": "Iceberg calving is a complex natural fracture process and a dominant cause of mass loss from the floating ice shelves on the margins of the Antarctic ice sheet. There is concern that rapid changes at these ice shelves can destabilize parts of the ice sheet and accelerate their contribution to sea-level rise. The goal of this project is to understand and simulate the fracture mechanics of calving and to develop physically-consistent calving schemes for ice-sheet models. This would enable more reliable estimation of Antarctic mass loss by reducing the uncertainty in projections. The research plan is integrated with an education and outreach plan that aims to (1) enhance computational modeling skills of engineering and Earth science students through a cross-college course and a high-performance computing workshop and (2) increase participation and diversity in engineering and sciences by providing interdisciplinary research opportunities to undergraduates and by deploying new cyberlearning tools to engage local K-12 students in the Metro Nashville Public Schools in computational science and engineering, and glaciology.\u003cbr/\u003e\u003cbr/\u003eThis project aims to provide fundamental understanding of iceberg calving by advancing the frontiers in computational fracture mechanics and nonlinear continuum mechanics and translating it to glaciology. The project investigates crevasse propagation using poro-damage mechanics models for hydrofracture that are consistent with nonlinear viscous ice rheology, along with the thermodynamics of refreezing in narrow crevasses at meter length scales. It will develop a fracture-physics based scheme to better represent calving in ice-sheet models using a multiscale method. The effort will also address research questions related to calving behavior of floating ice shelves and glaciers, with the goal of enabling more reliable prediction of calving fronts in whole-Antarctic ice-sheet simulations over decadal-to-millennial time scales.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "United States Of America; GLACIER MOTION/ICE SHEET MOTION", "locations": "United States Of America", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Duddu, Ravindra", "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "CAREER: Fracture Mechanics of Antarctic Ice Shelves and Glaciers - Representing Iceberg Calving in Ice Sheet Models and Developing Cyberlearning Tools for Outreach", "uid": "p0010423", "west": null}, {"awards": "2021699 Trusel, Luke", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic ice sheet daily surface melt detection from ASCAT (2007-2022); ASCAT-ERA5 Antarctic Peninsula Daily Surface Meltwater Production (2007-2022); Trusel et al 2022, Geophysical Research Letters: Publication data and code", "datasets": [{"dataset_uid": "200364", "doi": "10.5281/zenodo.7995998", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Antarctic ice sheet daily surface melt detection from ASCAT (2007-2022)", "url": "https://zenodo.org/record/7995998"}, {"dataset_uid": "200363", "doi": "10.5281/zenodo.6374343", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Trusel et al 2022, Geophysical Research Letters: Publication data and code", "url": "https://zenodo.org/record/6374343"}, {"dataset_uid": "200362", "doi": "10.5281/zenodo.7995543", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "ASCAT-ERA5 Antarctic Peninsula Daily Surface Meltwater Production (2007-2022)", "url": "https://zenodo.org/record/7995543"}], "date_created": "Fri, 02 Jun 2023 00:00:00 GMT", "description": "Melting of snow and ice at the surface of the Antarctic ice sheet can lead to the formation of meltwater lakes, an important precursor to ice-shelf collapse and accelerated ice-sheet mass loss. Understanding the present state of Antarctic surface melt provides a baseline to gauge how quickly melt impacts could evolve in the future and to reduce uncertainties in estimates of future sea-level rise. \r\n\r\nThis project used a suite of complimentary measurements from Earth-observing satellites, ground observations, and numerical climate models to enhance understanding of surface melt and lakes, as well as the processes linking these systems. The project supported the scientific training of a postdoctoral associate, a graduate student, and several undergraduate researchers. In addition, the project aimed to promote public scientific literacy and the broadening of quantitative skills for high-school students through the development and implementation of an educational unit in a partnership with an education and outreach expert and two high school teachers.\r\n\r\nWe identified that surface lake drainages on East Antarctica\u2019s Amery Ice Shelf closely correspond to peaks in the daily amplitude of ocean tides. This research indicates that tidal-induced flexure inherent to the ice shelf grounding zone when combined with sufficient surface meltwater volumes can trigger ice shelf surface lake drainages (Trusel et al., 2022). In addition, we developed new estimates of surface melting across the Antarctic ice sheet using satellite and reanalysis data. First, we developed and implemented a pan-Antarctic ice sheet surface melt detection method applied to C-band Advanced Scatterometer (ASCAT) radar backscatter data. These binary melt presence/absence data were then combined with radar backscatter and ERA5 reanalysis outputs to estimate daily rates of surface meltwater production (in mm of water equivalence) across the Antarctic Peninsula region. These data therefore provide a new, observationally based dataset to investigate the intensity and drivers of surface melting in Antarctica\u2019s highest-melt region, and with which to evaluate climate model simulations. This method and an assessment of the resulting data are the subject of a forthcoming manuscript. \r\n\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "ICE SHEETS; Antarctica; Surface Hydrology", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Trusel, Luke; Moussavi, Mahsa", "platforms": null, "repo": "Zenodo", "repositories": "Zenodo", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Water on the Antarctic Ice Sheet: Quantifying Surface Melt and Mapping Supraglacial Lakes", "uid": "p0010422", "west": -180.0}, {"awards": "1644256 Costa, Daniel; 1643575 Kanatous, Shane; 1644004 Trumble, Stephen", "bounds_geometry": "POLYGON((-66.534369 -52.962091,-65.3857434 -52.962091,-64.2371178 -52.962091,-63.0884922 -52.962091,-61.9398666 -52.962091,-60.791241 -52.962091,-59.6426154 -52.962091,-58.4939898 -52.962091,-57.3453642 -52.962091,-56.1967386 -52.962091,-55.048113 -52.962091,-55.048113 -54.530129,-55.048113 -56.098167000000004,-55.048113 -57.666205000000005,-55.048113 -59.234243,-55.048113 -60.802281,-55.048113 -62.370319,-55.048113 -63.938357,-55.048113 -65.506395,-55.048113 -67.074433,-55.048113 -68.642471,-56.1967386 -68.642471,-57.3453642 -68.642471,-58.4939898 -68.642471,-59.6426154 -68.642471,-60.791241 -68.642471,-61.9398666 -68.642471,-63.0884922 -68.642471,-64.2371178 -68.642471,-65.3857434 -68.642471,-66.534369 -68.642471,-66.534369 -67.074433,-66.534369 -65.506395,-66.534369 -63.938356999999996,-66.534369 -62.370319,-66.534369 -60.802281,-66.534369 -59.234243,-66.534369 -57.666205,-66.534369 -56.098167000000004,-66.534369 -54.530129,-66.534369 -52.962091))", "dataset_titles": "Data from: Whiskers provide time-series of toxic and essential trace elements, Se:Hg molar ratios, and stable isotope values of an apex Antarctic predator, the leopard seal; Leopard Seal Diving behavior data; Leopard Seal movement data", "datasets": [{"dataset_uid": "601689", "doi": "10.15784/601689", "keywords": "Antarctica; Antarctic Peninsula; Biota; Body Mass; Diving Behavior; Leopard Seal; Movement Data; Seals", "people": "Costa, Daniel", "repository": "USAP-DC", "science_program": null, "title": "Leopard Seal movement data", "url": "https://www.usap-dc.org/view/dataset/601689"}, {"dataset_uid": "200361", "doi": "https://doi.org/10.5061/dryad.ksn02v75b", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Data from: Whiskers provide time-series of toxic and essential trace elements, Se:Hg molar ratios, and stable isotope values of an apex Antarctic predator, the leopard seal", "url": "https://datadryad.org/stash/dataset/doi:10.5061%2Fdryad.ksn02v75b"}, {"dataset_uid": "601690", "doi": "10.15784/601690", "keywords": "Antarctica; Antarctic Peninsula; Biota; Body Mass; Diving Behavior; Leopard Seal; Seals", "people": "Costa, Daniel", "repository": "USAP-DC", "science_program": null, "title": "Leopard Seal Diving behavior data", "url": "https://www.usap-dc.org/view/dataset/601690"}], "date_created": "Fri, 12 May 2023 00:00:00 GMT", "description": "This research project is a multidisciplinary effort that brings together a diverse team of scientists from multiple institutions together to understand the foraging behavior and physiology of leopard seals and their role in the Southern Ocean food web. The project will examine the physiology and behavior of leopard seals to in an effort to determine their ability to respond to potential changes in their habitat and foraging areas. Using satellite tracking devices the team will examine the movement and diving behavior of leopard seals and couple this information with measurements of their physiological capacity. The project will determine whether leopard seals- who feed on diverse range of prey- are built differently than their deep diving relatives the Weddell and elephant seal who feed on fish and squid. The team will also determine whether leopard seals are operating at or near their physiological capability to determine how much, if any, ?reserve capacity? they might have to forage and live in changing environments. A better understanding of their home ranges, movement patterns, and general behavior will also be informative to help in managing human-leopard seal interactions. The highly visual nature of the data and analysis for this project lends itself to public and educational display and outreach, particularly as they relate to the changing Antarctic habitats. The project will use the research results to educate the public on the unique physiological and ecological adaptations to extreme environments seen in diving marine mammals, including adaptations to exercise under low oxygen conditions and energy utilization, which affect and dictate the lifestyle of these exceptional organisms. The results of the project will also contribute to the broader understanding that may enhance the aims of managing marine living resources.\u003cbr/\u003e\u003cbr/\u003eThe leopard seal is an apex predator in the Antarctic ecosystem. This project seeks to better understand the ability of the leopard seal to cope with a changing environment. The project will first examine the foraging behavior and habitat utilization of leopard seals using satellite telemetry. Specifically, satellite telemetry tags will be used to obtain dive profiles and movement data for individuals across multiple years. Diet and trophic level positions across multiple temporal scales will then be determined from physiological samples (e.g., blood, vibrissae, blubber fatty acids, stable isotopes, fecal matter). Oceanographic data will be integrated with these measures to develop habitat models that will be used to assess habitat type, habitat utilization, habitat preference, and home range areas for individual animals. Diet composition for individual seals will be evaluated to determine whether specific animals are generalists or specialists. Second, the team will investigate the physiological adaptations that allow leopard seals to be apex predators and determine to what extent leopard seals are working at or near their physiological limit. Diving behavior and physiology of leopard seals will be evaluated (for instance the aerobic dive limit for individual animals and skeletal muscle adaptations will be determined for diving under hypoxic conditions). Data from time-depth recorders will be used to determine foraging strategies for individual seals, and these diving characteristics will be related to physiological variables (e.g., blood volume, muscle oxygen stores) to better understand the link between foraging behavior and physiology. The team will compare myoglobin storage in swimming muscles associated with both forelimb and hind limb propulsion and the use of anaerobic versus aerobic metabolic systems while foraging.", "east": -55.048113, "geometry": "POINT(-60.791241 -60.802281)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; Diving Behavior; MAMMALS; MARINE ECOSYSTEMS; Movement Patterns; Leopard Seal", "locations": "Antarctic Peninsula", "north": -52.962091, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Costa, Daniel; Trumble, Stephen J; Kanatous, Shane", "platforms": null, "repo": "USAP-DC", "repositories": "Dryad; USAP-DC", "science_programs": null, "south": -68.642471, "title": "Collaborative Research: Foraging Ecology and Physiology of the Leopard Seal", "uid": "p0010419", "west": -66.534369}, {"awards": "2137376 Porazinska, Dorota; 2137377 Bergstrom, Anna; 2137375 Schmidt, Steven; 2137378 Varsani, Arvind", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 10 May 2023 00:00:00 GMT", "description": "Cryoconite holes are sediment-filled melt holes in the surface of glaciers that can be important sites of active microbial life in an otherwise mostly frozen and barren landscape. Previous studies in the McMurdo Dry Valleys, Antarctica suggest that viral infections of microbes, and a general lack of fertilizers (i.e., nutrients), may be important factors shaping the development and functioning of microbial communities in cryoconite holes. The researchers propose an experimental approach to understand how nutrient limitation affects diversity (number of species) and overall abundance of microbes, and how the diversity and abundance of microbes in turn affects the diversity, abundance, and infection type of viruses that parasitize the microbes in cryoconite sediments. The researchers will use sediments previously collected from Antarctic glaciers that have varying concentrations of viruses and nutrients, to set up a nutrient-addition experiment to determine how nutrients affect microbial and viral population dynamics. The results will deepen our understanding of how microbial communities in general are shaped by nutrients and viruses and give new insights into the functioning of viruses in extremely cold environments. The researchers will publish their findings in scientific journals and will share their discoveries with K-12 students from rural schools in collaboration with the Pinhead Institute and will connect undergraduate students from under-represented minorities to polar research through participation in the universitys Science, Technology, Engineering \u0026 Mathematics Routes Uplift Research Program. Outreach will be achieved through videos produced and distributed by a professional science communicator. The research advances a National Science Foundation goal of expanding fundamental knowledge of Antarctic systems, biota, and processes by utilizing the unique characteristics of the Antarctic region as a science observing platform. \r\n\r\nThe Principal Investigators propose an experimental approach to understand how nutrient limitation affects microbial diversity and abundances and their cascading effects on virus diversity, abundance, and mode of infection (lysis vs. lysogeny) in Antarctic cryoconite holes. Cryoconite holes are ideal natural microcosms for manipulative studies, not available in other cryospheric ecosystems. The PIs will use previously collected cryoconite from across a gradient of both viral diversity and nutrient levels to address questions about key limiting nutrients and microbial-viral community dynamics in cryoconite sediments. Nutrient manipulation experiments will be conducted in a growth chamber that closely approximates the light and temperature regime of in situ cryoconite holes to test three core hypotheses: (1) phosphorus availability limits microbial productivity and abundance in cryoconite holes; (2) relaxing nutrient limitation in cryoconite from low-diversity glaciers will increase species diversity, leading microbial communities to resemble those found on more nutrient-rich glaciers; (3) relaxing nutrient limitation will increase the diversity and abundance of viruses by increasing the availability of suitable hosts, and decrease the prevalence of lysogenic infections. By manipulating nutrient limitation within a realistic range, this project will help verify hypothesized phosphorus limitation of Antarctic cryoconite holes and will extend understanding of the connections between nutrients, diversity, and viral infection dynamics in the cryosphere more generally. A better understanding of these dynamics in cryoconite sediments improves the ability of scientists to forecast future impacts of environmental changes in the cryosphere.\r\n\r\nThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "AQUATIC ECOSYSTEMS; Taylor Valley", "locations": "Taylor Valley", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Varsani, Arvind; Porazinska, Dorota; Schmidt, Steven; Bergstrom, Anna", "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Role of Nutrient Limitation and Viral Interactions on Antarctic Microbial Community Assembly: A Cryoconite Microcosm Study", "uid": "p0010418", "west": null}, {"awards": "1543383 Postlethwait, John; 2232891 Postlethwait, John; 1947040 Postlethwait, John", "bounds_geometry": "POLYGON((-180 -37,-144 -37,-108 -37,-72 -37,-36 -37,0 -37,36 -37,72 -37,108 -37,144 -37,180 -37,180 -42.3,180 -47.6,180 -52.9,180 -58.2,180 -63.5,180 -68.8,180 -74.1,180 -79.4,180 -84.69999999999999,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84.7,-180 -79.4,-180 -74.1,-180 -68.8,-180 -63.5,-180 -58.2,-180 -52.9,-180 -47.6,-180 -42.300000000000004,-180 -37))", "dataset_titles": "aBSREL tests for episodic diversifying selection on hemoglobin genes in notothenioids.; MEME tests of sites evolving under episodic diversifying selection in notothenioid hemoglobin genes.; Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae); Notothenioid hemoglobin protein 3D modeling.; Notothenioid species tree used in the study.; Phylogenetic trees of hemoglobin proteins in notothenioids.; Rates of hemoglobin evolution among genes and across notothenioid species.; RELAX tests for pervasive changes in strength of natural selection on hemoglobin genes in notothenioids.", "datasets": [{"dataset_uid": "601729", "doi": "10.15784/601729", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "people": "Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "Rates of hemoglobin evolution among genes and across notothenioid species.", "url": "https://www.usap-dc.org/view/dataset/601729"}, {"dataset_uid": "601811", "doi": null, "keywords": "Antarctica; Bellingshausen Sea; Cryosphere; Southern Ocean", "people": "Desvignes, Thomas; McDowell, Jan; Cheng, Chi-Hing; Biesack, Ellen; Steinberg, Deborah; Hilton, Eric; Corso, Andrew", "repository": "USAP-DC", "science_program": "LTER", "title": "Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae)", "url": "https://www.usap-dc.org/view/dataset/601811"}, {"dataset_uid": "601722", "doi": "10.15784/601722", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Gene; Hemoglobin; Icefish; Notothenioid; Plunderfish; Sub-Antarctic", "people": "Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "Phylogenetic trees of hemoglobin proteins in notothenioids.", "url": "https://www.usap-dc.org/view/dataset/601722"}, {"dataset_uid": "601721", "doi": "10.15784/601721", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Gene; Hemoglobin; Icefish; Notothenioid; Plunderfish; Sub-Antarctic", "people": "Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "Notothenioid species tree used in the study.", "url": "https://www.usap-dc.org/view/dataset/601721"}, {"dataset_uid": "601732", "doi": "10.15784/601732", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "people": "Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "Notothenioid hemoglobin protein 3D modeling.", "url": "https://www.usap-dc.org/view/dataset/601732"}, {"dataset_uid": "601731", "doi": "10.15784/601731", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "people": "Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "RELAX tests for pervasive changes in strength of natural selection on hemoglobin genes in notothenioids.", "url": "https://www.usap-dc.org/view/dataset/601731"}, {"dataset_uid": "601730", "doi": "10.15784/601730", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "people": "Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "MEME tests of sites evolving under episodic diversifying selection in notothenioid hemoglobin genes.", "url": "https://www.usap-dc.org/view/dataset/601730"}, {"dataset_uid": "601728", "doi": "10.15784/601728", "keywords": "Antarctica; Cold Adaptation; Cryonotothenioid; Dragonfish; Eleginopsioidea; Fish; Gene; Genetic Analysis; Hemoglobin; Icefish; Notothenioid; Notothenioid Fishes; Plunderfish; Sub-Antarctic", "people": "Postlethwait, John; Desvignes, Thomas", "repository": "USAP-DC", "science_program": null, "title": "aBSREL tests for episodic diversifying selection on hemoglobin genes in notothenioids.", "url": "https://www.usap-dc.org/view/dataset/601728"}], "date_created": "Wed, 03 May 2023 00:00:00 GMT", "description": "Antarctic notothenioid fishes, also known as cryonotothenioids, inhabit the icy and highly oxygenated waters surrounding the Antarctic continent after diverging from notothenioids inhabiting more temperate waters. Notothenioid hemoglobin and blood parameters are known to have evolved along with the establishment of stable polar conditions, and among Antarctic notothenioids, icefishes are evolutionary oddities living without hemoglobin following the deletion of all functional hemoglobin genes from their genomes. In this project, we investigate the evolution of hemoglobin genes and gene clusters across the notothenioid radiation until their loss in the icefish ancestor after its divergence from the dragonfish lineage to understand the forces, mechanisms, and potential causes for hemoglobin gene loss in the icefish ancestor.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "FISH; Icefish; Cryonotothenioid; Gene; Plunderfish; Eleginopsioidea; AQUATIC ECOSYSTEMS; Dragonfish; Sub-Antarctic; Notothenioid; Blood; Hemoglobin", "locations": "Sub-Antarctic", "north": -37.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Desvignes, Thomas; Postlethwait, John", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Evolution of hemoglobin genes in notothenioid fishes", "uid": "p0010417", "west": -180.0}, {"awards": "1745078 Brook, Edward J.", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Atmospheric methane across the Last Glacial Maximum and deglaciation from the GISP2, NEEM and WAIS Divide ice cores ; Atmospheric methane interpolar difference and four-box troposphere model output across the Last Glacial Maximum and Deglaciation; Carbon-13 and Deuterium isotopic composition of atmospheric methane across Heinrich Stadial 4, and Dansgaard Oesgher Event 8, WAIS Divide Replicate Ice Core, Antarctica; Carbon-13 isotopic composition of atmospheric methane across Heinrich Stadials 1 and 5, and Dansgaard Oesgher Event 12, WAIS Divide Ice Core, Antarctica", "datasets": [{"dataset_uid": "601736", "doi": "10.15784/601736", "keywords": "Antarctica; Greenland; Methane; Paleoclimate; West Antarctic Ice Sheet", "people": "Lee, James; Edwards, Jon S.; M\u00fchl, Michaela; Schmitt, Jochen; Buizert, Christo; Blunier, Thomas; Rosen, Julia; Riddell-Young, Benjamin; Brook, Edward J.; Fischer, Hubertus; Martin, Kaden", "repository": "USAP-DC", "science_program": null, "title": "Atmospheric methane interpolar difference and four-box troposphere model output across the Last Glacial Maximum and Deglaciation", "url": "https://www.usap-dc.org/view/dataset/601736"}, {"dataset_uid": "601813", "doi": "10.15784/601813", "keywords": "Abrupt Climate Change; Antarctica; Atmospheric Gases; Biogeochemical Cycles; Carbon Cycle; Cryosphere; Greenhouse Gas; Methane; West Antarctic Ice Sheet Divide", "people": "Clark, Reid; Brook, Edward J.; Iseli, Rene; Riddell-Young, Benjamin; Lee, James; Schmitt, Jochen; Fischer, Hubertus; Bauska, Thomas; Menking, Andy", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Carbon-13 and Deuterium isotopic composition of atmospheric methane across Heinrich Stadial 4, and Dansgaard Oesgher Event 8, WAIS Divide Replicate Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601813"}, {"dataset_uid": "601683", "doi": "10.15784/601683", "keywords": "Antarctica; Methane; West Antarctic Ice Sheet", "people": "Riddell-Young, Benjamin", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Carbon-13 isotopic composition of atmospheric methane across Heinrich Stadials 1 and 5, and Dansgaard Oesgher Event 12, WAIS Divide Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601683"}, {"dataset_uid": "601737", "doi": "10.15784/601737", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Greenland; Ice Core Records; Methane; West Antarctic Ice Sheet", "people": "Riddell-Young, Benjamin; Brook, Edward J.; Edwards, Jon S.; Lee, James; Rosen, Julia; Martin, Kaden", "repository": "USAP-DC", "science_program": null, "title": "Atmospheric methane across the Last Glacial Maximum and deglaciation from the GISP2, NEEM and WAIS Divide ice cores ", "url": "https://www.usap-dc.org/view/dataset/601737"}], "date_created": "Mon, 01 May 2023 00:00:00 GMT", "description": "This project will develop methods to measure the ratios of carbon-13 to carbon-12, and heavy to light hydrogen in methane in air trapped in ice cores. The ratios of the different forms of carbon and hydrogen are \"fingerprints\" of different sources of this gas in the past--for example wetlands in the tropics versus methane frozen in the sea floor. Once the analysis method is developed, the measurements will be used to examine why methane changed abruptly in the past, both during the last ice age, and during previous warm periods. The data will be used to understand how methane sources like wildfires, methane hydrates, and wetlands respond to climate change. This information is needed to understand future risks of large changes in methane in the atmosphere as Earth warms. \u003cbr/\u003e\u003cbr/\u003eThe project involves two tasks. First, the investigators will build and test a gas extraction system for methane isotopic measurements using continuous flow methods, with the goal of equaling or bettering the precision attained by the few other laboratories that make these measurements. The system will be interfaced with existing mass spectrometers at Oregon State University. The system consists of a vacuum chamber and sequence of traps, purification columns, and furnaces that separate methane from other gases and convert it to carbon dioxide or hydrogen for mass spectrometry. Second, the team will measure the isotopic composition of methane across large changes in concentration associated with two past interglacial periods and during abrupt methane changes of the last ice age. These measurements will be used to understand if the main reason for these concentration changes is climate-driven changes in emissions from wetlands, or whether other sources are involved, for example methane hydrates or wildfires.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Ice Sheet; TRACE GASES/TRACE SPECIES; METHANE", "locations": "Antarctic Ice Sheet", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores", "uid": "p0010416", "west": -180.0}, {"awards": "2133684 Fierer, Noah", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 07 Apr 2023 00:00:00 GMT", "description": "Not all of Antarctica is covered in ice. In fact, soils are common to many parts of Antarctica, and these soils are often unlike any others found on Earth. Antarctic soils harbor unique microorganisms able to cope with the extremely cold and dry conditions common to much of the continent. For decades, microbiologists have been drawn to the unique soils in Antarctica, yet critical knowledge gaps remain. Most notably, it is unclear what properties allow certain microbes to thrive in Antarctic soils. By using a range of methods, this project is developing comprehensive model that discovers the unique genomic features of soils diversity, distributions, and adaptations that allow Antarctic soil microbes to thrive in extreme environments. The proposed work will be relevant to researchers in many fields, including engineers seeking to develop new biotechnologies, ecologists studying the contributions of these microbial communities to the functioning of Antarctic ecosystems, microbiologists studying novel microbial adaptations to extreme environmental conditions, and even astrobiologists studying the potential for life on Mars. More generally, the proposed research presents an opportunity to advance our current understanding of the microbial life found in one of the more distinctive microbial habitats on Earth, a habitat that is inaccessible to many scientists and a habitat that is increasingly under threat from climate change.\r\n\r\nThe research project explores the microbial diversity in Antarctic soils and links specific features to different soil types and environmental conditions. The overarching questions include: What microbial taxa are found in a variety of Antarctic environments? What are the environmental preferences of specific taxa or lineages? What are the genomic and phenotypic traits of microorganisms that allow them to persist in extreme environments and determine biogeographical differneces? This project will analyze archived soils collected from across Antarctica by a network of international collaborators, with samples selected to span broad gradients in soil and site conditions. The project uses cultivation-independent, high-throughput genomic analysis methods and cultivation-dependent approaches to analyze bacterial and fungal communities in soil samples. The results will be used to predict the distributions of specific taxa and lineages, obtain genomic information for the more ubiquitous and abundant taxa, and quantify growth responses in vitro across gradients in temperature, moisture, and salinity. This integration of ecological, environmental, genomic, and trait-based information will provide a comprehensive understanding of microbial life in Antarctic soils. This project will also help facilitate new collaborations between scientists across the globe while providing undergraduate students with \u0027\u0027hands-on\u0027\u0027 research experiences that introduce the next generation of scientists to the field of Antarctic biology.\r\n\r\nThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "FUNGI; BACTERIA/ARCHAEA; TERRESTRIAL ECOSYSTEMS; Antarctica", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Fierer, Noah; Quandt, Alisha A; Lemonte, Joshua", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: ANT LIA Integrating Genomic and Phenotypic Analyses to understand Microbial Life in Antarctic Soils", "uid": "p0010414", "west": -180.0}, {"awards": "2306186 Schroeder, Dustin", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 05 Apr 2023 00:00:00 GMT", "description": "This project will develop a new ice-penetrating radar system that can simultaneously map glacier geometry and glacier flow along repeat profiles. Forecasting an ice-sheet\u2019s contribution to sea level requires an estimate for the initial ice-sheet geometry and the parameters that govern ice flow and slip across bedrock. Existing ice-sheet models cannot independently determine this information from conventional observations of ice-surface velocities and glacier geometry. This introduces substantial uncertainty into simulations of past and future ice-sheet behavior. Thus, this new radar capability is conceived to provide the needed data to support higher-fidelity simulations of past and future ice-sheet behavior and more accurate projections of future sea level.\r\n\r\nThe new radar system will integrate two existing radars (the multi-channel coherent radio-echo depth sounder and the accumulation radar) developed by the Center for the Remote Sensing of Ice Sheets, as well as adding new capabilities. An eight-element very high frequency (VHF; 140-215 MHz) array will have sufficient cross-track aperture to swath map internal layers and the ice-sheet base in three dimensions. A single ultra high frequency (UHF; 600-900 MHz) antenna will have the range and phase resolution to map internal layer displacement with 0.25-mm precision. The VHF array will create 3D mappings of layer geometry that enable measurements of vertical velocities by accounting for spatial offsets between repeat profiles and changing surface conditions. The vertical displacement measurement will then be made by determining the difference in radar phase response recorded by the UHF antenna for radar profiles collected at the same locations at different times. The UHF antenna will be dual-polarized and thus capable of isolating both components of complex internal reflections. This should enable inferences of ice crystal orientation fabric and widespread mapping of ice viscosity. Initial field testing of the radar will occur on the McMurdo Ice Shelf and then progress to Thwaites Glacier, Antarctica. The dual-band radar system technology and processing algorithms will be developed with versatile extensible hardware and user-friendly software so that this system will serve as a prototype for a future community radar system.\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "ICE SHEETS; Greenland", "locations": "Greenland", "north": -60.0, "nsf_funding_programs": "Antarctic Instrumentation and Facilities; Polar Cyberinfrastructure", "paleo_time": null, "persons": "Schroeder, Dustin", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "EAGER: Community-Driven Ice Penetrating Radar Systems for Observing Complex Ice-Sheet Thermal Structure and Flow", "uid": "p0010413", "west": -180.0}, {"awards": "1542902 Chereskin, Teresa; 2001646 Chereskin, Teresa", "bounds_geometry": "POLYGON((-68 -54,-66.7 -54,-65.4 -54,-64.1 -54,-62.8 -54,-61.5 -54,-60.2 -54,-58.9 -54,-57.6 -54,-56.3 -54,-55 -54,-55 -55,-55 -56,-55 -57,-55 -58,-55 -59,-55 -60,-55 -61,-55 -62,-55 -63,-55 -64,-56.3 -64,-57.6 -64,-58.9 -64,-60.2 -64,-61.5 -64,-62.8 -64,-64.1 -64,-65.4 -64,-66.7 -64,-68 -64,-68 -63,-68 -62,-68 -61,-68 -60,-68 -59,-68 -58,-68 -57,-68 -56,-68 -55,-68 -54))", "dataset_titles": "Joint Archive for shipboard ADCP data; World Ocean Database", "datasets": [{"dataset_uid": "200355", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "World Ocean Database", "url": "https://www.nodc.noaa.gov/OC5/SELECT/dbsearch/dbsearch.html"}, {"dataset_uid": "200354", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Joint Archive for shipboard ADCP data", "url": "https://uhslc.soest.hawaii.edu/sadcp/"}], "date_created": "Fri, 03 Mar 2023 00:00:00 GMT", "description": "The Antarctic Circumpolar Current (ACC) is the largest current on the planet, flowing west to east around Antarctica, forming a barrier that separates warmer waters to the north from colder waters to the south. Ocean eddies (like atmospheric storms) break through the ACC barrier, transferring heat across the ACC towards Antarctica. When warmer ocean waters intrude onto the Antarctic continental shelves, they contribute to glacial melt and ice shelf retreat. Over the past several decades, the Southern Ocean has warmed and winds have increased due to climate change. Somewhat surprisingly the ACC, though pushed by faster winds, has not accelerated; a faster current would present a stronger barrier to heat transfer. Instead, ocean eddies have increased. These eddies are concentrated at 6-7 \"hot spots\". Drake Passage is one of these hot spots. As the narrowest land gap on the entire circumpolar path of the ACC, Drake Passsage is an ideal monitoring spot. However, it is also one of the windiest and roughest stretches of water on the globe. The only ship that crosses Drake Passage year-round is the USAP supply vessel for Palmer Station, making it a unique platform to monitor the currents and temperature with a minimum of personnel and resources. The Drake Passage time series of upper ocean currents and temperature is now in its 24th year. The upper ocean temperature measurements have found significant warming in Drake Passage. The upper ocean current measurements have confirmed that the ACC has remained steady on average but have also revealed a complicated filamented current structure. Combining temperature and current measurements has provided a better understanding of heat transfer across the ACC by eddies. The time series has also provided valuable ground-truth for satellite measurements and for numerical model predictions looking at the entire ACC. Our studies are focused on examining low-frequency variability - seasonal, interannual, and decadal - in order to provide baselines from which to evaluate and interpret physical and biogeochemical changes occurring in the Southern Ocean. \r\n", "east": -55.0, "geometry": "POINT(-61.5 -59)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": true, "keywords": "R/V LMG; Drake Passage; WATER TEMPERATURE; Antarctic Circumpolar Current; Heat Flux", "locations": "Drake Passage", "north": -54.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Chereskin, Teresa; Sprintall, Janet", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -64.0, "title": "High Resolution Underway Air-Sea Observations in Drake Passage for Climate Science", "uid": "p0010409", "west": -68.0}, {"awards": "1543511 Stephens, Britton; 1543457 Munro, David", "bounds_geometry": "POLYGON((-73 -53,-71.2 -53,-69.4 -53,-67.6 -53,-65.8 -53,-64 -53,-62.2 -53,-60.4 -53,-58.6 -53,-56.8 -53,-55 -53,-55 -54.4,-55 -55.8,-55 -57.2,-55 -58.6,-55 -60,-55 -61.4,-55 -62.8,-55 -64.2,-55 -65.6,-55 -67,-56.8 -67,-58.6 -67,-60.4 -67,-62.2 -67,-64 -67,-65.8 -67,-67.6 -67,-69.4 -67,-71.2 -67,-73 -67,-73 -65.6,-73 -64.2,-73 -62.8,-73 -61.4,-73 -60,-73 -58.6,-73 -57.2,-73 -55.8,-73 -54.4,-73 -53))", "dataset_titles": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the Southern Ocean, Drake Passage and South Atlantic Ocean in 2018, processed by NOAA (NCEI Accession 0184338); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, Drake Passage, South Atlantic Ocean in 2022 (NCEI Accession 0276577); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Atlantic Ocean in 2021 (NCEI Accession 0246983); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean from 2019-02-16 to 2020-02-11 (NCEI Accession 0208838); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean in 2020 (NCEI Accession 0225445); Underway measurements of pCO2 in the Surface Waters and the Atmosphere During the ARSV Laurence M. Gould 2017 Expeditions processed by NOAA (NCEI Accession 0170337)", "datasets": [{"dataset_uid": "200350", "doi": "https://doi.org/10.25921/3ysc-pm11", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean from 2019-02-16 to 2020-02-11 (NCEI Accession 0208838)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200351", "doi": "https://doi.org/10.25921/z0pk-pv81", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean in 2020 (NCEI Accession 0225445)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200352", "doi": "https://doi.org/10.25921/f94g-zp40", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Atlantic Ocean in 2021 (NCEI Accession 0246983)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200353", "doi": "https://doi.org/10.25921/fq0a-7y11", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, Drake Passage, South Atlantic Ocean in 2022 (NCEI Accession 0276577)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200348", "doi": "https://doi.org/10.7289/v5tq5zt1", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Underway measurements of pCO2 in the Surface Waters and the Atmosphere During the ARSV Laurence M. Gould 2017 Expeditions processed by NOAA (NCEI Accession 0170337)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200349", "doi": "https://doi.org/10.25921/b4jn-ef56", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the Southern Ocean, Drake Passage and South Atlantic Ocean in 2018, processed by NOAA (NCEI Accession 0184338)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}], "date_created": "Wed, 22 Feb 2023 00:00:00 GMT", "description": "The Southern Ocean plays a key role in modulating the global carbon cycle, but the size and even the sign of the flux of carbon dioxide between the ocean and atmosphere in this region is still uncertain. This is in part due to the lack of measurements in this remote region of the world ocean. This project continues a multi-year time series of shipboard chemical measurements in the Drake Passage to detect changes in the ocean carbon cycle and to improve the understanding of mechanisms driving natural variability and long-term change in the Southern Ocean. More specifically, this project is a continuation of the collection of underway upper ocean measurements of the surface partial pressure of carbon dioxide during crossings of the Drake Passage by the Antarctic Research and Supply Vessel Laurence M. Gould. This project also includes collection and analysis of discrete samples relevant to ocean carbon cycle studies including macronutrient concentrations, total carbon dioxide concentrations, and the carbon isotopic composition of total carbon dioxide. The Drake Passage data are made readily available to the international science community and serve as both validation and constraints of remotely sensed observations and numerical coupled earth systems models.", "east": -55.0, "geometry": "POINT(-64 -60)", "instruments": null, "is_usap_dc": true, "keywords": "Drake Passage; NUTRIENTS; BIOGEOCHEMICAL CYCLES; DISSOLVED GASES; TRACE GASES/TRACE SPECIES", "locations": "Drake Passage", "north": -53.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Munro, David; Sweeney, Colm; Lovenduski, Nicole S; Stephens, Britton", "platforms": null, "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -67.0, "title": "Collaborative Research: Investigating Biogeochemical Fluxes and Linkages To Climate Change With Multi-Scale Observations In The Drake Passage", "uid": "p0010407", "west": -73.0}, {"awards": null, "bounds_geometry": null, "dataset_titles": "Biogeochemical data from sediment core at Inexpressible Island in Ross Sea Region during the 2015-2016 Antarctic field investigation", "datasets": [{"dataset_uid": "601660", "doi": "10.15784/601660", "repository": "USAP-DC", "science_program": null, "title": "Biogeochemical data from sediment core at Inexpressible Island in Ross Sea Region during the 2015-2016 Antarctic field investigation", "url": "http://www.usap-dc.org/view/dataset/601660"}], "date_created": "Mon, 30 Jan 2023 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Sediment Core Data", "locations": "Antarctica", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Liu, Xiaodong", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "NNX16AL07G TBD", "bounds_geometry": null, "dataset_titles": "KIS-1 ROV Icefin Missions", "datasets": [{"dataset_uid": "601625", "doi": "10.15784/601625", "repository": "USAP-DC", "science_program": null, "title": "KIS-1 ROV Icefin Missions", "url": "http://www.usap-dc.org/view/dataset/601625"}], "date_created": "Wed, 14 Dec 2022 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Grounding Line; Grounding Zone; Ice Shelf; Kamb Ice Stream; Ross Ice Shelf", "locations": "Antarctica; Antarctica; Ross Ice Shelf; Kamb Ice Stream; Kamb Ice Stream", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Lawrence, Justin; Schmidt, Britney", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "1542756 Koutnik, Michelle", "bounds_geometry": "POLYGON((-180 -77,-179.5 -77,-179 -77,-178.5 -77,-178 -77,-177.5 -77,-177 -77,-176.5 -77,-176 -77,-175.5 -77,-175 -77,-175 -77.9,-175 -78.8,-175 -79.7,-175 -80.6,-175 -81.5,-175 -82.4,-175 -83.3,-175 -84.2,-175 -85.1,-175 -86,-175.5 -86,-176 -86,-176.5 -86,-177 -86,-177.5 -86,-178 -86,-178.5 -86,-179 -86,-179.5 -86,180 -86,177.5 -86,175 -86,172.5 -86,170 -86,167.5 -86,165 -86,162.5 -86,160 -86,157.5 -86,155 -86,155 -85.1,155 -84.2,155 -83.3,155 -82.4,155 -81.5,155 -80.6,155 -79.7,155 -78.8,155 -77.9,155 -77,157.5 -77,160 -77,162.5 -77,165 -77,167.5 -77,170 -77,172.5 -77,175 -77,177.5 -77,-180 -77))", "dataset_titles": "Beardmore Glacier model in \u0027icepack\u0027", "datasets": [{"dataset_uid": "200339", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Beardmore Glacier model in \u0027icepack\u0027", "url": "https://github.com/danshapero/beardmore"}], "date_created": "Mon, 12 Dec 2022 00:00:00 GMT", "description": "In this project we investigated glaciers that drain ice from the East Antarctic Ice Sheet through the Transantarctic Mountains into the present-day Ross Ice Shelf. The outlet glaciers that flow through the Transantarctic Mountains have thinned significantly over the past 15,000 years, especially as they retreated from Last Glacial Maximum highstands to their present-day grounding lines. At certain locations and for certain glaciers, rocks or bedrock have been sampled to provide constraints on the timing of when ice retreated from these locations. In the locations where geochronological data are available we can use these data as direct constraints on ice-flow models that simulate ice elevation change over time. The intellectual merit of this work is using ice-flow models to spatially and temporally extrapolate between these limited geochronological data points, which enables new understanding of glacier evolution. \r\n\r\nThe mountainous topography in this region is complex, and there are limited measurements of the topography beneath the ice of the Transantarctic outlet glaciers. Since the topography of the glacier bed is an important control on ice flow and is a necessary boundary condition in models we developed a new gridded bed product at Beardmore Glacier, the one location where sufficient data were available, and we compared this to continent-scale gridded bed products. We found that for this glacier, the BedMachine v1 product was reasonably similar to the Beardmore Glacier bed topography measurements; our limited evaluation suggests that the BedMachine product may be sufficient at other Transantarctic outlets where bed measurements are not available, but that other compilations of bed topography data that do not include information about ice flow directions do not provide reliable results. Using these data and available geochronological constraints we investigated Beardmore Glacier evolution since the Last Glacial Maximum using simplified (flowline) models of ice flow.\r\n\r\nIn addition to flowline modeling at Beardmore Glacier, we developed a flow-model setup using the open-source \u0027icepack\u0027 model that uses the shallow stream equations and resolves flow in both the x and y directions. The key value added over flowline (or parameterized flowband) models is that this can capture converging and diverging ice flow, variable side wall and bottom drag, and other geometric complexities. In these simulations we can evaluate the past accumulation, ice influx, and ice outflux to compare controls on deglaciation to data constraints on the chronology of deglaciation.\r\n\r\nWe also used a flowline model to investigate the Darwin-Hatherton Glacier System. Exposure ages and radiocarbon ages of glacial deposits at four locations alongside Hatherton and Darwin glaciers record several hundred meters of late Pleistocene to early Holocene thickening relative to present. Deglaciation was relatively complex at this site, and we also found that Byrd glacier likely contributed ice to the catchment of the Darwin-Hatherton glacier system during the last glacial maximum, and that subsequent convergent flow from Byrd and Mulock glaciers during deglaciation complicated the response of the Darwin-Hatherton system. These new insights can be used on their own to better understand local deglaciation, and can also be used to evaluate regional or continent-scale model calculations.\r\n\r\nSeparately, we investigated the general response of outlet glaciers to different sources of climate forcing. We found that outlet glaciers have a characteristically different response over time to surface-mass-balance forcing applied over the interior than to oceanic forcing applied at the grounding line. Our models demonstrated that ocean forcing first engages the fast, local response and then the slow adjustment of interior ice, whereas surface-mass-balance forcing is dominated by the slow interior adjustment. These insights contributed to our general understanding of how outlet glaciers may have evolved over time.\r\n\r\nOur new model investigations provide a framework that can be applied at other Transantarctic outlet glaciers where geochronological data are available. In particular, our \u0027icepack\u0027 setup is an archived and documented resource for the community. These tools are available for future investigations, including additional investigations at Beardmore Glacier and at other Transantarctic Mountain outlet glaciers. Scientific broader impacts include that this contributes to our understanding of the past behavior of East Antarctic ice, which provides an important constraint on the future evolution of Antarctica. Our team has engaged in public outreach and has engaged students in this research. Two graduate students led in aspects of this work, and have since gone on to research positions after their PhD.", "east": -175.0, "geometry": "POINT(170 -81.5)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS; Transantarctic Mountains; GLACIER THICKNESS/ICE SHEET THICKNESS", "locations": "Transantarctic Mountains", "north": -77.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Koutnik, Michelle; Smith, Ben; Conway, Howard; Shapero, Daniel", "platforms": null, "repo": "GitHub", "repositories": "GitHub", "science_programs": null, "south": -86.0, "title": "Holocene Deglaciation of the Western Ross Embayment: Constraints from East Antarctic Outlet Glaciers", "uid": "p0010398", "west": 155.0}, {"awards": "1644004 Trumble, Stephen", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Data from: Whiskers provide time-series of toxic and essential trace elements, Se:Hg molar ratios, and stable isotope values of an apex Antarctic predator, the leopard seal", "datasets": [{"dataset_uid": "200338", "doi": "doi:10.5061/dryad.ksn02v75b", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Data from: Whiskers provide time-series of toxic and essential trace elements, Se:Hg molar ratios, and stable isotope values of an apex Antarctic predator, the leopard seal", "url": "https://datadryad.org/stash/share/h6UwXvfhZG26jtPTtDqyXNMnx2UWknOqmv05EBz6A10"}], "date_created": "Tue, 06 Dec 2022 00:00:00 GMT", "description": "This research project is a multidisciplinary effort that brings together a diverse team of scientists from multiple institutions together to understand the foraging behavior and physiology of leopard seals and their role in the Southern Ocean food web. The project will examine the physiology and behavior of leopard seals to in an effort to determine their ability to respond to potential changes in their habitat and foraging areas. Using satellite tracking devices the team will examine the movement and diving behavior of leopard seals and couple this information with measurements of their physiological capacity. The project will determine whether leopard seals- who feed on diverse range of prey- are built differently than their deep diving relatives the Weddell and elephant seal who feed on fish and squid. The team will also determine whether leopard seals are operating at or near their physiological capability to determine how much, if any, ?reserve capacity? they might have to forage and live in changing environments. A better understanding of their home ranges, movement patterns, and general behavior will also be informative to help in managing human-leopard seal interactions. The highly visual nature of the data and analysis for this project lends itself to public and educational display and outreach, particularly as they relate to the changing Antarctic habitats. The project will use the research results to educate the public on the unique physiological and ecological adaptations to extreme environments seen in diving marine mammals, including adaptations to exercise under low oxygen conditions and energy utilization, which affect and dictate the lifestyle of these exceptional organisms. The results of the project will also contribute to the broader understanding that may enhance the aims of managing marine living resources.\u003cbr/\u003eThe leopard seal is an apex predator in the Antarctic ecosystem. This project seeks to better understand the ability of the leopard seal to cope with a changing environment. The project will first examine the foraging behavior and habitat utilization of leopard seals using satellite telemetry. Specifically, satellite telemetry tags will be used to obtain dive profiles and movement data for individuals across multiple years. Diet and trophic level positions across multiple temporal scales will then be determined from physiological samples (e.g., blood, vibrissae, blubber fatty acids, stable isotopes, fecal matter). Oceanographic data will be integrated with these measures to develop habitat models that will be used to assess habitat type, habitat utilization, habitat preference, and home range areas for individual animals. Diet composition for individual seals will be evaluated to determine whether specific animals are generalists or specialists. Second, the team will investigate the physiological adaptations that allow leopard seals to be apex predators and determine to what extent leopard seals are working at or near their physiological limit. Diving behavior and physiology of leopard seals will be evaluated (for instance the aerobic dive limit for individual animals and skeletal muscle adaptations will be determined for diving under hypoxic conditions). Data from time-depth recorders will be used to determine foraging strategies for individual seals, and these diving characteristics will be related to physiological variables (e.g., blood volume, muscle oxygen stores) to better understand the link between foraging behavior and physiology. The team will compare myoglobin storage in swimming muscles associated with both forelimb and hind limb propulsion and the use of anaerobic versus aerobic metabolic systems while foraging.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "MAMMALS; Stable Isotopes; Livingston Island", "locations": "Livingston Island", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Trumble, Stephen J", "platforms": null, "repo": "Dryad", "repositories": "Dryad", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Foraging Ecology and Physiology of the Leopard Seal", "uid": "p0010394", "west": -180.0}, {"awards": "2130663 Neff, Peter", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic Subsea Cable Workshop Report", "datasets": [{"dataset_uid": "601691", "doi": "10.15784/601691", "keywords": "Antarctica; Communication; Internet; Report", "people": "Neff, Peter; Andreasen, Julia; Roop, Heidi A; Pundsack, Jonathan W; Howe, Bruce; Jacobs, Gwen; Lassner, David; Yoshimi, Garrett; Timm, Kristin", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Subsea Cable Workshop Report", "url": "https://www.usap-dc.org/view/dataset/601691"}], "date_created": "Tue, 01 Nov 2022 00:00:00 GMT", "description": "Current networking capacity at McMurdo Station is insufficient to even be considered broadband, with a summer population of up to 1000 people sharing what is equivalent to the connection enjoyed by a typical family of three in the United States. The changing Antarctic ice sheets and Southern Ocean are large, complex systems that require cutting edge technology to do cutting edge research, with remote technology becoming increasingly useful and even necessary to monitor changes at sufficient spatial and temporal scales. Antarctic science also often involves large data-transfer needs not currently met by existing satellite communication infrastructure. This workshop will gather representatives from across Antarctic science disciplinesfrom astronomy to zoologyas well as research and education networking experts to explore the scientific advances that would be enabled through dramatically increased real-time network connectivity, and also consider opportunities for subsea cable instrumentation.\r\n\r\nThis workshop will assess the importance of a subsea fiber optic cable for high-capacity real-time connectivity in the US Antarctic Program, which is at the forefront of some of the greatest climate-related challenges facing our planet. The workshop will: (1) document unmet or poorly met current scientific and logistic needs for connectivity; (2) explore connectivity needs for planned future research and note the scientific advances that would be possible if the full value of modern cyberinfrastructure-empowered research could be brought to the Antarctic research community; and (3) identify scientific opportunities in planning a fully instrumented communication cable as a scientific observatory. Due to the ongoing COVID-19 pandemic, the workshop will be hosted and streamed online. While the workshop will be limited to invited personnel in order to facilitate a collaborative working environment, broad community input will be sought via survey and via comment on draft outputs. A workshop summary document and report will be delivered to NSF. Increasing US Antarctic connectivity by orders of magnitude will be transformative for science and logistics, and it may well usher in a new era of Antarctic science that is more accessible, efficient and sustainable.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Minneapolis, MN; SNOW/ICE", "locations": "Minneapolis, MN; Antarctica", "north": -60.0, "nsf_funding_programs": "Polar Cyberinfrastructure", "paleo_time": null, "persons": "Pundsack, Jonathan W; Roop, Heidi A", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "2021 Antarctic Subsea Cable Workshop: High-Speed Connectivity Needs to Advance US Antarctic Science", "uid": "p0010389", "west": -180.0}, {"awards": "2135695 Emslie, Steven; 2135696 Polito, Michael", "bounds_geometry": "POLYGON((-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70.8,-180 -71.6,-180 -72.4,-180 -73.2,-180 -74,-180 -74.8,-180 -75.6,-180 -76.4,-180 -77.2,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -77.2,160 -76.4,160 -75.6,160 -74.8,160 -74,160 -73.2,160 -72.4,160 -71.6,160 -70.8,160 -70,162 -70,164 -70,166 -70,168 -70,170 -70,172 -70,174 -70,176 -70,178 -70,-180 -70))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 28 Oct 2022 00:00:00 GMT", "description": "Stable isotope analyses of carbon and nitrogen (\u03b413C and \u03b415N) are commonly used to investigate animal migration, foraging locations and diet, especially in marine species that can travel over great distances. One other stable isotope, sulfur (\u03b434S), is not as commonly used but is increasingly being applied to refine and corroborate data obtained from carbon and nitrogen analyses. Collagen is one of the best tissues for these analyses as it is abundant in bone, preserves well, and can be easily extracted for analysis. In the Ross Sea region, the cold, dry environment has been conductive for the preservation of Ad\u00e9lie penguin (Pygoscelis adeliae) bones, feathers, eggshell and even mummified remains, at active and abandoned colonies that date from before the Last Glacial Maximum (\u003e45,000 yrs ago) through the Holocene. Most of these colonies are associated with one of three polynyas, or highly productive areas of open water surrounded by sea ice in the Ross Sea. Thus, this species is an excellent bioindicator for marine conditions, past and present, and its colonies have appeared and disappeared throughout this region with changing climate and sea ice regimes for millennia. Current warming trends are inducing relatively rapid ecological responses by this species and some of the largest colonies in the Ross Sea are likely to be abandoned in the next 50 years from rising sea level. The recently established Ross Sea Marine Protected Area aims to protect Ad\u00e9lie penguins and other species in this region from human impacts and knowledge on how this species responds to climate change, past and present, will support this goal. \r\n\r\nWe propose to investigate ecological responses in diet and foraging behavior of the Ad\u00e9lie penguin to known climatic events that occurred in the middle to late Holocene, specifically, before, during and after a warming period known as the penguin \u2018optimum\u2019 at 2000 - 4000 cal yr before present (BP). We will apply for the first time a suite of three stable isotope analyses (\u03b413C, \u03b415N, \u03b434S) on chick bones and feathers, as well as prey remains, from active and abandoned colonies in the Ross Sea. We will use existing tissue samples (~60-80 bones) collected by PI Emslie with NSF support since 2001 and supplement these with newly collected samples of bones and feathers in this project. We will conduct compound-specific isotope analyses of carbon on essential amino acids from collagen from a selected sample of 30-40 bones that span the past 5000 yrs to provide corroboratory information. We will apply three-dimensional Bayesian niche models and/or community metrics using R scripts in these analyses to identify isotopic \u2018signatures\u2019 of existing and past foraging grounds and polynyas used by Ad\u00e9lie penguins in the southern, central, and northern Ross Sea. This four-year study will the first of its kind to apply multiple stable isotope analyses to investigate a living species of seabird over millennia in a region where it still exists today. \r\n\r\nBroader Impacts:\r\nThe PIs are committed to public engagement and enhancement of K-12 education in the STEM sciences. Broader impacts of this research will include support and training for one Ph.D., two M.S., and eight undergraduate students in the Department of Biology and Marine Biology, and two M.A. students in the Watson School of Education at the University of North Carolina Wilmington (UNCW). The last two students will continue to expand on a detailed polar curriculum that was initiated in previous NSF grants for 2nd and 4th grade students, and most recently for 9-12th grade students now available on PI Emslie\u2019s website (www.uncw.edu/penguins). Additional curricula for K-12 students will be designed and tested in this project, which will include visitation to local K-12 schools. As in previous awards, we will focus on schools that serve historically under-represented groups in the sciences. We will work with the UNCW Center for Education in STEM Sciences to assess the efficacy of this new curricula. All curricula will be uploaded on the Educational Resource Commons website. Field work will include blogs and active question-answer sessions with students at these schools. We will continue to post project information and updates on PI Emslie\u2019s website and YouTube channel. Our partnership with tour ship companies will provide a platform for onboard lectures on the importance of scientific research as well as citizen science opportunities for another sector of the public. This proposal requires fieldwork in the Antarctic.\r\n", "east": -180.0, "geometry": "POINT(170 -74)", "instruments": null, "is_usap_dc": true, "keywords": "Climate Change; Adelie Penguin; Foraging Ecology; Ross Sea; PENGUINS; Holocene; Stable Isotopes", "locations": "Ross Sea", "north": -70.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Emslie, Steven; Lane, Chad S; Polito, Michael", "platforms": null, "repositories": null, "science_programs": null, "south": -78.0, "title": "Collaborative Research: Using Multiple Stable Isotopes to Investigate Middle to Late Holocene Ecological Responses by Adelie Penguins in the Ross Sea", "uid": "p0010388", "west": 160.0}, {"awards": "1543533 Johnson, Jesse; 1543530 van der Veen, Cornelis", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 19 Oct 2022 00:00:00 GMT", "description": "Van der Veen/1543530\u003cbr/\u003e\u003cbr/\u003eThe objective of this research is to gain better understanding of the West Antarctic ice flow in the transition region from grounded ice to floating ice shelves and investigate the conditions that can initiate and sustain major retreat of these glaciers. Several major Antarctic outlet glaciers and ice streams will be investigated using a suite of observational techniques and modeling tools. Glaciers include Thwaites Glacier, which has become a focal point in the discussion of West Antarctic retreat, Whillans Ice Stream as an example of the archetype ice stream, and Byrd Glacier, a major outlet glacier draining East Antarctica through the Transantarctic Mountains into the Ross Ice Shelf. This study will investigate whether the ongoing changes in these glaciers will lead to long-term mass loss (the onset of ice sheet collapse), or whether these glaciers will quickly stabilize with a new geometry. \u003cbr/\u003e\u003cbr/\u003eTo adequately incorporate the dynamic behavior of outlet glaciers and ice streams requires inclusion of the relevant physical processes, and the development of regional models that employ a numerical grid with a horizontal grid spacing sufficiently refined to capture smaller-scale bed topographic features that may control the flow of these glaciers. This award revisits the issue of stability of marine-terminating glaciers whose grounding line is located on a retrograded bed slope. In particular, an attempt will be made to resolve the question whether observed rapid changes are the result of perturbations at the terminus or grounding line, or whether these changes reflect ice-dynamical forcing over the grounded reaches. High-resolution satellite imagery will be used to investigate ice-flow perturbations on smaller spatial scales than has been done before, to evaluate the importance of localized sites of high basal resistance on grounding-line stability. This collaborative project involves a range of modeling strategies including force-budget analysis, flow-band modeling, Full Stokes modeling for local studies, and using the Ice Sheet System Model developed at JPL for regional modeling. Broader Impacts include training two graduate students in computer simulations and ice sheet modeling algorithms. The work will also expand on a web-based interactive flowline model, so that it includes more realistic grounding line dynamics.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Ice Sheet Dynamics; MODELS; Iceberg Calving; GLACIERS/ICE SHEETS; Numerical Glacier Modeling; Basal Sliding; Antarctica", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "van der Veen, Cornelis; Stearns, Leigh; Paden, John", "platforms": "OTHER \u003e MODELS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Stability and Dynamics of Antarctic Marine Outlet Glaciers", "uid": "p0010387", "west": -180.0}, {"awards": "1917009 Thomson, Stuart; 1917176 Siddoway, Christine; 1916982 Teyssier, Christian", "bounds_geometry": "POLYGON((-160.16 -67.15,-154.572 -67.15,-148.984 -67.15,-143.39600000000002 -67.15,-137.808 -67.15,-132.22 -67.15,-126.632 -67.15,-121.04400000000001 -67.15,-115.456 -67.15,-109.868 -67.15,-104.28 -67.15,-104.28 -68.165,-104.28 -69.18,-104.28 -70.19500000000001,-104.28 -71.21000000000001,-104.28 -72.225,-104.28 -73.24,-104.28 -74.255,-104.28 -75.27,-104.28 -76.285,-104.28 -77.3,-109.868 -77.3,-115.456 -77.3,-121.044 -77.3,-126.632 -77.3,-132.22 -77.3,-137.808 -77.3,-143.396 -77.3,-148.98399999999998 -77.3,-154.572 -77.3,-160.16 -77.3,-160.16 -76.285,-160.16 -75.27,-160.16 -74.255,-160.16 -73.24,-160.16 -72.225,-160.16 -71.21000000000001,-160.16 -70.19500000000001,-160.16 -69.18,-160.16 -68.165,-160.16 -67.15))", "dataset_titles": "Apatite fission track thermochronology data for detrital minerals, offshore clasts, and bedrock; U-Pb detrital zircon geochronological data, obtained by LA-ICP-MS", "datasets": [{"dataset_uid": "200332", "doi": "", "keywords": null, "people": null, "repository": "in progress", "science_program": null, "title": "U-Pb detrital zircon geochronological data, obtained by LA-ICP-MS", "url": ""}, {"dataset_uid": "200333", "doi": "", "keywords": null, "people": null, "repository": "in progress", "science_program": null, "title": "Apatite fission track thermochronology data for detrital minerals, offshore clasts, and bedrock", "url": ""}], "date_created": "Wed, 19 Oct 2022 00:00:00 GMT", "description": "Sediment records off the coast of Marie Byrd Land (MBL), Antarctica suggest frequent and dramatic changes in the size of the West Antarctic Ice Sheet (WAIS) over short (tens of thousands of years) and long (millions of years) time frames in the past. WAIS currently overrides much of MBL and covers the rugged and scoured bedrock landscape. The ice sheet carved narrow linear troughs that reach depths of two to three thousand meters below sea level as outlet glaciers flowed from the interior of the continent to the oceans. As a result, large volumes of fragmented continental bedrock were carried out to the seabed. The glaciers cut downward into a region of crystalline rocks (i.e. granite) that display a significant temperature change as a function of rock depth. The strong geothermal gradient in the bedrock is favorable for determining when the bedrock became exhumed, or \"uncovered\" by action of the overriding icesheet or other processes. Our approach takes advantage of a reference horizon, or paleogeotherm, established when high-T mineral thermochronometers across Marie Byrd Land (MBL) cooled from temperatures of \u003e800\u00b0 C to 300\u00b0 C, due to rapid regional extension at ~100 Ma . The event imparted a signature through which the subsequent Cenozoic landscape history can be explored: MBL\u0027s elevated geothermal gradient, sustained during the Cenozoic, created favorable conditions for sensitive apatite and zircon low-T thermochronometers to record bedrock cooling related to glacial incision. \r\n\r\nAnalyzing the chemistry of minerals (zircon and apatite) within fragments of eroded rock will reveal the rate and timing of the bedrock erosion and development of topography in West Antarctica. This collaborative project addresses the following questions: When did the land become high enough for a large ice sheet to form? What was the regional pre-glacial topography? Under what climate conditions, and at what point in the growth of an ice sheet, did glaciers begin to cut sharply into bedrock to form the narrow troughs that flow seaward? The research will lead to greater understanding of past Antarctic ice sheet fluctuations and identify precise timing of glacial incisionm which will clarify the onset of WAIS glacier incision and assess the evolution of Cenozoic paleo-topography. The collaborative project provides training for one graduate and 8 undergraduate students in STEM. These students, together with PIs, will refine West Antarctic ice sheet history and obtain results that pertain to the international societal response to contemporary ice sheet change and its global consequences. \r\n\r\nThe methods used for the research include: \r\n\u2022Low-temperature (T) thermochronology and Pecube 3-D thermo-kinematic modeling, applied to the timing and characterizatio episodes of glacial erosional incision. \r\n\u2022Single-grain double- and triple-dating of zircon and apatite, to determine the detailed crustal thermal evolution of the region, enabling the research team to identify the comparative topographic influences on glaciation versus bedrock uplift induced by Eocene to present tectonism/magmatism. \r\n\r\nStudents and PIs employed state-of-the-art analytical facilities in Arizona and Minnesota, expanding the geo- and thermochronologic history of MBL from bedrock samples and offshore sedimentary deposits. The temperature and time data we acquired will provide constraints on paleotopography, isostasy, and the thermal evolution of MBL that will be modeled in 3D using Pecube model simulations. Within hot crust, less incision is required to expose bedrock containing the distinct thermochronometric profile; a prediction we are testing through use of inverse Pecube 3-D models of the thermal field through which bedrock and detrital samples cooled. Using results from Pecube, the ICI-Hot team will examine time-varying topography formed in response to changes in erosion rates, topographic relief, geothermal gradient and/or flexural isostatic rigidity. These effects are manifestations of dynamic processes in the WAIS, including ice sheet loading, ice volume fluctuations, relative motion upon crustal faults, and magmatism-related elevation increase across the MBL dome. The project makes use of pre-existing sample collections housed at the US Polar Rock Repository, IODP\u0027s Gulf Coast Core Repository, and the OSU Marine and Geology Repository. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -104.28, "geometry": "POINT(-132.22 -72.225)", "instruments": null, "is_usap_dc": true, "keywords": "Marie Byrd Land; GLACIERS/ICE SHEETS; Zircon; Subglacial Topography; FIELD SURVEYS; TECTONICS; Ice Sheet; Thermochronology; Apatite; ROCKS/MINERALS/CRYSTALS; Erosion; United States Of America; LABORATORY", "locations": "United States Of America; Marie Byrd Land", "north": -67.15, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC", "persons": "Siddoway, Christine; Thomson, Stuart; Teyssier, Christian", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "in progress", "repositories": "in progress", "science_programs": null, "south": -77.3, "title": "Collaborative Research: Ice sheet erosional interaction with hot geotherm in West Antarctica", "uid": "p0010386", "west": -160.16}, {"awards": "2037963 Smith, Heidi", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 11 Oct 2022 00:00:00 GMT", "description": "Glacial ice cores serve as a museum back in time, providing detailed records of past climatic conditions. In addition to chronological records such as temperature, chemistry and gas composition, ice provides a unique environment for preserving microbes and other biological materials through time. These microbes provide invaluable insight into the physiological capabilities necessary for survival in the Earths cryosphere and other icy planetary bodies, yet little is known about them. This award supports fundamental research into the activity of microbes in ice, and directly supports major research priorities regarding Antarctic biota identified in the 2015 National Academies of Sciences, Engineering, and Medicine report, A Strategic Vision for NSF Investments in Antarctic and Southern Ocean Research. The broader impacts of this work are that it will be relevant to researchers across paleoclimate and biological fields. It will support two early career researchers, a graduate and an undergraduate student who will conduct laboratory analyses, participate in outreach activities, publish papers in scientific journals and present at conferences. \r\n\r\nThis work will use previously collected ice cores to investigate englacial microbial activity from the Holocene back to the Last Glacial Maximum from the blue ice area of Taylor Glacier, Antarctica. The proposal identified making significant contributions to 1) investing how Antarctic organisms evolve and adapt to changing environment, 2) understanding how microbes alter the preservation of paleorecord-relevant gas and trace element information in ice cores, and 3) identifying microbial life in cores and their activity in relation to dust depositional events. Two recently developed complementary techniques (bio-orthogonal noncanonical amino acid tagging and deuterium isotope probing) in combination with Raman Confocal Microspectroscopy will be used to assess and quantify microbial activity in ice. During phase one of the project, these methods will be optimized using deaccessioned ice cores available at the National Science Foundations Ice Core Facility. In phase two, ice cores in a time series from the Taylor Glacier will be analyzed for geochemistry and microbial activity. Research results will provide a comprehensive view of englacial microbial communities, including their metabolic diversity and activity, and the effect of geochemical parameters on microbial assemblages from different climate periods. Given the dearth of information available on englacial microbial communities, the results of this research will be of particular significance.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Microbial Activity; LABORATORY; Paleoclimate; CAMP; Taylor Glacier; Microbiology; Alaska; ICE CORE RECORDS", "locations": "CAMP; Alaska; Taylor Glacier", "north": null, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Smith, Heidi; Foreman, Christine; Dieser, Markus", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "Life in Ice: Probing Microbial Englacial Activity through Time", "uid": "p0010385", "west": null}, {"awards": "1645087 Catchen, Julian", "bounds_geometry": null, "dataset_titles": "Chromosome-Level Genome Assembly and Circadian Gene Repertoire of the Patagonia Blennie Eleginops maclovinus\u2014The Closest Ancestral Proxy of Antarctic Cryonotothenioids; Evaluating Illumina-, Nanopore-, and PacBio-based genome assembly strategies with the bald notothen, Trematomus borchgrevinki; Genomics of Secondarily Temperate Adaptation in the Only Non-Antarctic Icefish", "datasets": [{"dataset_uid": "200381", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "Chromosome-Level Genome Assembly and Circadian Gene Repertoire of the Patagonia Blennie Eleginops maclovinus\u2014The Closest Ancestral Proxy of Antarctic Cryonotothenioids", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA917608"}, {"dataset_uid": "200330", "doi": "", "keywords": null, "people": null, "repository": "NCBI ", "science_program": null, "title": "Evaluating Illumina-, Nanopore-, and PacBio-based genome assembly strategies with the bald notothen, Trematomus borchgrevinki", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA861284"}, {"dataset_uid": "200380", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "Genomics of Secondarily Temperate Adaptation in the Only Non-Antarctic Icefish", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA857989"}, {"dataset_uid": "200331", "doi": "10.5061/dryad.ghx3ffbs3", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Evaluating Illumina-, Nanopore-, and PacBio-based genome assembly strategies with the bald notothen, Trematomus borchgrevinki", "url": "https://datadryad.org/stash/dataset/doi:10.5061/dryad.ghx3ffbs3"}], "date_created": "Mon, 10 Oct 2022 00:00:00 GMT", "description": "As plate tectonics pushed Antarctica into a polar position, by ~34 million years ago, the continent and its surrounding Southern Ocean (SO) became geographically and thermally isolated by the Antarctic Circumpolar Current. Terrestrial and marine glaciation followed, resulting in extinctions as well as the survival and radiation of unique flora and fauna. The notothenioid fish survived and arose from a common ancestral stock into tax with 120 species that dominates today\u0027s SO fish fauna. The Notothenioids evolved adaptive traits including novel antifreeze proteins for survival in extreme cold, but also suffered seemingly adverse trait loss including red blood cells in the icefish family, and the ability to mount cellular responses to mitigate heat stress ? otherwise ubiquitous across all life. This project aims to understand how the notothenoid genomes have changed and contributed to their evolution in the cold. The project will sequence, analyze and compare the genomes of two strategic pairs of notothenioid fishes representing both red-blooded and white-blooded species. Each pair will consist of one Antarctic species and one that has readapted to the temperate waters of S. America or New Zealand. The project will also compare the Antarctic species genomes to a genome of the closet non-Antarctic relative representing the temperate notothenioid ancestor. The work aims to uncover the mechanisms that enabled the adaptive evolution of this ecologically vital group of fish in the freezing Southern Ocean, and shed light on their adaptability to a warming world. The finished genomes will be made available to promote and advance Antarctic research and the project will host a symposium of Polar researchers to discuss the cutting edge developments regarding of genomic adaptations in the polar region.\u003cbr/\u003eDespite subzero, icy conditions that are perilous to teleost fish, the fish fauna of the isolated Southern Ocean (SO) surrounding Antarctica is remarkably bountiful. A single teleost group - the notothenioid fishes - dominate the fauna, comprising over 120 species that arose from a common ancestor. When Antarctica became isolated and SO temperatures began to plunge in early Oligocene, the prior temperate fishes became extinct. The ancestor of Antarctic notothenioids overcame forbidding polar conditions and, absent niche competition, it diversified and filled the SO. How did notothenioids adapt to freezing environmental selection pressures and achieve such extraordinary success? And having specialized to life in chronic cold for 30 myr, can they evolve in pace with today\u0027s warming climate to stay viable? Past studies of Antarctic notothenioid evolutionary adaptation have discovered various remarkable traits including the key, life-saving antifreeze proteins. But life specialized to cold also led to paradoxical trait changes such as the loss of the otherwise universal heat shock response, and of the O2-transporting hemoglobin and red blood cells in the icefish family. A few species interestingly regained abilities to live in temperate waters following the escape of their ancestor out of the freezing SO. \u003cbr/\u003eThis proposed project is the first major effort to advance the field from single trait studies to understanding the full spectrum of genomic and genetic responses to climatic and environmental change during notothenioid evolution, and to evaluate their adaptability to continuing climate change. To this end, the project will sequence the genomes of four key species that embody genomic responses to different thermal selection regimes during notothenioids\u0027 evolutionary history, and by comparative analyses of genomic structure, architecture and content, deduce the responding changes. Specifically, the project will (i) obtain whole genome assemblies of the red-blooded T. borchgrevinki and the S. American icefish C. esox; (ii) using the finished genomes from (i) as template, obtain assemblies of the New Zealand notothenioid N. angustata, and the white-blooded icefish C. gunnari, representing a long (11 myr) and recent (1 myr) secondarily temperate evolutionary history respectively. Genes that are under selection in the temperate environment but not in the Antarctic environment can be inferred to be directly necessary for that environment and the reverse is also true for genes under selection in the Antarctic but not in the temperate environment. Further, genes important for survival in temperate waters will show parallel selection between N. angustata and C. esox despite the fact that the two fish left the Antarctic at far separated time points. Finally, gene families that expanded due to strong selection within the cold Antarctic should show a degradation of duplicates in the temperate environment. The project will test these hypotheses using a number of techniques to compare the content and form of genes, the structure of the chromosomes containing those genes, and through the identification of key characters, such as selfish genetic elements, introns, and structural variants.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Genome Assembly; FISH; McMurdo Sound; Icefish; SHIPS; Notothenioid; Puerto Natales, Chile", "locations": "McMurdo Sound; Puerto Natales, Chile", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Catchen, Julian; Cheng, Chi-Hing", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "NCBI", "repositories": "Dryad; NCBI; NCBI ", "science_programs": null, "south": null, "title": "Evolutionary Genomic Responses in Antarctic Notothenioid Fishes", "uid": "p0010384", "west": null}, {"awards": "2135186 Baumberger, Tamara; 2135185 Resing, Joseph; 2135184 Arrigo, Kevin", "bounds_geometry": "POLYGON((155 -61,156.5 -61,158 -61,159.5 -61,161 -61,162.5 -61,164 -61,165.5 -61,167 -61,168.5 -61,170 -61,170 -61.2,170 -61.4,170 -61.6,170 -61.8,170 -62,170 -62.2,170 -62.4,170 -62.6,170 -62.8,170 -63,168.5 -63,167 -63,165.5 -63,164 -63,162.5 -63,161 -63,159.5 -63,158 -63,156.5 -63,155 -63,155 -62.8,155 -62.6,155 -62.4,155 -62.2,155 -62,155 -61.8,155 -61.6,155 -61.4,155 -61.2,155 -61))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 30 Sep 2022 00:00:00 GMT", "description": "Part 1.\r\nPhytoplankton blooms throughout the world support critical marine ecosystems and help remove harmful CO2 from the atmosphere. Traditionally, it has been assumed that phytoplankton blooms in the Southern Ocean are stimulated by iron from either the continental margin or sea-ice. However, recent work demonstrates that hydrothermal vents may be an additional iron source for phytoplankton blooms. This enhancement of phytoplankton productivity by different iron sources supports rich marine ecosystems and leads to the sequestration of C in the deep ocean. Our proposed work will uncover the importance of hydrothermal activity in stimulating a large phytoplankton blooms along the southern boundary of the Antarctic Circumpolar Current just north of the Ross Sea. It will also lead towards a better understanding of the overall impact of hydrothermal activity on the C cycle in the Southern Ocean, which appears to trigger local hotspots of enhanced biological activity which are a potential as a sink for atmospheric CO2. This project will encourage the participation of underrepresented groups in ocean sciences, as well as providing educational opportunities for high school and undergraduate students, through three different programs. Stanford University\u2019s Summer Undergraduate Research in Geoscience and Engineering (SURGE) program provides undergraduates from different US universities and diverse cultural backgrounds the opportunity to spend a summer doing a research project at Stanford. The Stanford Earth Summer Undergraduate Research Program (SESUR) is for Stanford undergraduates who want to learn more about environmental science by performing original research. Finally, Stanford\u2019s School of Earth, Energy, and Environmental Sciences High School Internship Program enables young scientists to serve as mentors, prepares high school students for college, and serves to strengthen the partnership between Stanford and local schools. Students present their results at the Fall AGU meeting as part of the AGU Bright STaRS program. This project will form the basis of at least two Ph.D. dissertations. The Stanford student will participate in Stanford\u2019s Woods Institute Rising Environmental Leaders Program (RELP), a year-round program that helps graduate students hone their leadership and communication skills to maximize the impact of their research. The graduate student will also participate in Stanford\u2019s Grant Writing Academy where they will receive training in developing and articulating research strategies to tackle important scientific questions. \r\n\r\nPart 2.\r\nThis interdisciplinary program combines satellite and ship-based measurements of a large poorly understood phytoplankton bloom (the AAR bloom) in the northwestern Ross Sea sector of the Southern Ocean with a detailed modeling study of the physical processes linking deep dissolved iron (DFe) reservoirs to the surface phytoplankton bloom. Prior to the cruise, we will implement a numerical model (CROCO) for our study region so that we can better understand the circulation, plumes, turbulence, fronts, and eddy field around the AAR bloom and how they transport and mix hydrothermally produced DFe vertically. Post cruise, observations of the vertical distribution of 3He (combined with DMn and DFe), will be used as initial conditions for a passive tracer in the model, and tracer dispersal will be assessed to better quantify the role of the various turbulent processes in upwelling DFe-rich waters to the upper ocean. The satellite-based component of the program will characterize the broader sampling region before, during, and after our cruise. During the cruise, our automated software system at Stanford University will download and process images of sea ice concentration, Chl a concentration, sea surface temperature (SST), and SSH and send them electronically to the ship. Operationally, our goal is to use all available satellite data and preliminary model results to target shipboard sampling both geographically and temporally to optimize sampling of the AAR bloom. We will use available BGC-Argo float data to help characterize the AAR bloom. In collaboration with SOCCOM, we will deploy additional BGC-Argo floats (if available) during our transit through the study area to allow us to better characterize the bloom. The centerpiece of our program will be a 40-day process study cruise in austral summer. The cruise will consist of an initial \u201cradiator\u201d pattern of hydrographic surveys/sections along the AAR followed by CTDs to selected submarine volcanoes. When/if eddies are identified, they will be sampled either during or after the initial surveys. The radiator pattern, or parts thereof, will be repeated 2-3 times. Hydrographic survey stations will include vertical profiles of temperature, salinity, oxygen, oxidation-reduction potential, light scatter, and PAR (400-700 nm). Samples will be collected for trace metals, ligands, 3He, and total suspended matter. Where intense hydrothermal activity is identified, samples for pH and total CO2 will also be collected to characterize the hydrothermal system. Water samples will be collected for characterization of macronutrients, and phytoplankton physiology, abundance, species composition, and size. During transits, we will continuously measure atmospheric conditions, current speed and direction, and surface SST, salinity, pCO2, and fluorescence from the ship\u2019s systems to provide detailed maps of these parameters. The ship will be used as a platform for conducting phytoplankton DFe bioassay experiments at key stations throughout the study region both inside and outside the bloom. We will also perform detailed comparisons of algal taxonomic composition, physiology, and size structure inside and outside the bloom to determine the potential importance of each community on local biogeochemistry.", "east": 170.0, "geometry": "POINT(162.5 -62)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; Antarctica; TRACE ELEMENTS; Hydrothermal Vent; Phytoplankton; Primary Production", "locations": "Antarctica", "north": -61.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Arrigo, Kevin; Thomas, Leif N; Baumberger, Tamara; Resing, Joseph", "platforms": null, "repositories": null, "science_programs": null, "south": -63.0, "title": "Collaborative Research: Understanding the Massive Phytoplankton Blooms over the Australian-Antarctic Ridge", "uid": "p0010381", "west": 155.0}, {"awards": "1644118 Dunbar, Robert", "bounds_geometry": "POLYGON((-108 -73,-107.3 -73,-106.6 -73,-105.9 -73,-105.2 -73,-104.5 -73,-103.8 -73,-103.1 -73,-102.4 -73,-101.7 -73,-101 -73,-101 -73.3,-101 -73.6,-101 -73.9,-101 -74.2,-101 -74.5,-101 -74.8,-101 -75.1,-101 -75.4,-101 -75.7,-101 -76,-101.7 -76,-102.4 -76,-103.1 -76,-103.8 -76,-104.5 -76,-105.2 -76,-105.9 -76,-106.6 -76,-107.3 -76,-108 -76,-108 -75.7,-108 -75.4,-108 -75.1,-108 -74.8,-108 -74.5,-108 -74.2,-108 -73.9,-108 -73.6,-108 -73.3,-108 -73))", "dataset_titles": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020", "datasets": [{"dataset_uid": "601611", "doi": "10.15784/601611", "keywords": "Amundsen Sea; Antarctica; Chemistry:Water; CTD; D18O; NBP0001; NBP0702; NBP0901; NBP1901; NBP2002; Oceans; Oxygen Isotope; R/v Nathaniel B. Palmer; Seawater Isotope; Southern Ocean", "people": "Hennig, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020", "url": "https://www.usap-dc.org/view/dataset/601611"}], "date_created": "Wed, 21 Sep 2022 00:00:00 GMT", "description": "Estimating Antarctic ice sheet growth or loss is important to predicting future sea level rise. Such estimates rely on field measurements or remotely sensed based observations of the ice sheet surface, ice margins, and or ice shelves. This work examines the introduction of freshwater into the ocean to surrounding Antarctica to track meltwater from continental ice. Polar ice is depleted in two stable isotopes, 18O and D, deuterium, relative to Southern Ocean seawater and precipitation. Measurements of seawater isotopic composition in conjunction with precise observations of seawater temperature and salinity, will permit discrimination of freshwater derived from melting glacial ice from that derived from regional precipitation or sea ice melt.\u003cbr/\u003e\u003cbr/\u003eThis research describes an accepted method for determining rates and locations of meltwater entering the oceans from polar ice sheets. As isotopic and salinity perturbations are cumulative in many Antarctic coastal seas, the method allows for the detection of any marked acceleration in meltwater introduction in specific regions, using samples collected and analyzed over a period of years to decades. Impact of the project derives from use of an independent method capable of constraining knowledge about current ice sheet melt rates, their stability and potential impact on sea level rise. The project allows for sample collection taken from foreign vessels of opportunity sailing in Antarctic waters, and subsequent sharing and interpretation of data. Research partners include the U.S., Korea, China, New Zealand, the United Kingdom, and Germany. Participating collaborators will collect seawater samples for isotopic and salinity analysis at Stanford University. USAP cruises will concentrate on sampling the Ross Sea, and the West Antarctic. The work plan includes interpretation of isotopic data using box model and mixing curve analyses as well as using isotope enabled ROMS (Regional Ocean Modeling System) models. The broader impacts of the research will include development of an educational module that illustrates the scientific method and how ocean observations help society understand how Earth is changing.", "east": -101.0, "geometry": "POINT(-104.5 -74.5)", "instruments": null, "is_usap_dc": true, "keywords": "Stable Isotopes; WATER TEMPERATURE; SALINITY; Oxygen Isotope; Meltwater Inventory; Pine Island Bay; OCEAN CHEMISTRY", "locations": "Pine Island Bay", "north": -73.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Dunbar, Robert", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.0, "title": "Estimation of Antarctic Ice Melt using Stable Isotopic Analyses of Seawater", "uid": "p0010380", "west": -108.0}, {"awards": "2138994 Kocot, Kevin; 2138993 Gerken, Sarah", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 20 Sep 2022 00:00:00 GMT", "description": "The overarching goal of this research is to use cumaceans as a model system to explore invertebrate adaptations to the changing Antarctic. This project will leverage integrative taxonomy, functional, comparative and evolutionary genomics, and phylogenetic comparative methods to understand the true diversity of Cumacea in the Antarctic, identify genes and gene families experiencing expansions, selection, or significant differential expression, generate a broadly sampled and robust phylogenetic framework for Cumacea based on transcriptomes and genomes, and explore rates and timing of diversification in Antarctic cumaceans. The project will contribute to understanding of gene gain/loss, positive selection, and differential gene expression as a function of adaptation of organisms to Antarctic habitats. Phylogenomic analyses will provide a robust phylogenetic framework for Southern Ocean Cumacea. Currently, the only -omics level data that exists for the Cumacea is one transcriptome. This project will generate 8 genomes from 8 species, about 250 transcriptomes from about 70 species, and approximately 470 COI and 16S barcodes from about 100 species. Beyond the immediate scope of the current project, the genomic resources will be leveraged by members of the polar biology and invertebrate zoology communities for diverse other uses ranging from PCR primer development to inference of ancestral population sizes. In addition, curated morphological reference collections will be deposited at the Smithsonian, Los Angeles County Natural History Museum, and in the New Zealand National Water and Atmospheric Research collection at Greta Point, to assist future researchers in identification of Antarctic cumaceans.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Benthic; SHIPS; Antarctic Peninsula; Antarctica; Biodiversity; Peracarida; ARTHROPODS; East Antarctica; Chile; BENTHIC; Cumacea; Ross Sea; Crustacea", "locations": "Antarctica; East Antarctica; Chile; Ross Sea; Antarctic Peninsula", "north": -60.0, "nsf_funding_programs": "Polar Special Initiatives; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": "NOT APPLICABLE", "persons": "Gerken, Sarah; Kocot, Kevin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: ANT LIA: Cumacean -Omics to Measure Mode of Adaptation to Antarctica (COMMAA)", "uid": "p0010379", "west": -180.0}, {"awards": "2218402 Fegyveresi, John", "bounds_geometry": "POLYGON((-115 -85.5,-113.5 -85.5,-112 -85.5,-110.5 -85.5,-109 -85.5,-107.5 -85.5,-106 -85.5,-104.5 -85.5,-103 -85.5,-101.5 -85.5,-100 -85.5,-100 -85.65,-100 -85.8,-100 -85.95,-100 -86.1,-100 -86.25,-100 -86.4,-100 -86.55,-100 -86.7,-100 -86.85,-100 -87,-101.5 -87,-103 -87,-104.5 -87,-106 -87,-107.5 -87,-109 -87,-110.5 -87,-112 -87,-113.5 -87,-115 -87,-115 -86.85,-115 -86.7,-115 -86.55,-115 -86.4,-115 -86.25,-115 -86.1,-115 -85.95,-115 -85.8,-115 -85.65,-115 -85.5))", "dataset_titles": "Multi-Site Brittle Ice Data and Measurements", "datasets": [{"dataset_uid": "601786", "doi": null, "keywords": "Antarctica; Brittle Ice; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Glaciology; Ice Core; Ice Core Records; Ice Core Records; Physical Properties; Simple Dome; Siple Dome; South Pole; SPICEcore; Subgrain Boundaries; WAIS Divide", "people": "Fegyveresi, John; Barnett, Samantha", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Multi-Site Brittle Ice Data and Measurements", "url": "https://www.usap-dc.org/view/dataset/601786"}], "date_created": "Mon, 19 Sep 2022 00:00:00 GMT", "description": "Brittle ice has been a long-standing and consistent challenge for ice-coring projects, complicating sampling, and introducing the possibility of contamination. Several procedures have been tested to reduce brittle damage to recovered cores, but many come with high monetary and time costs. Our background research suggests that bubble size and c-axis fabric are primary drivers for brittleness and are predictable from site characteristics, enabling prediction of brittleness before coring. We propose to improve understanding of the mechanisms involved in brittle ice onset and behavior, through targeted investigations of various ice physical properties, in carefully selected samples across multiple ice-core sites, in order to guide the upcoming Hercules Dome ice-core drilling and science communities. This project will involve collaboration between Northern Arizona University, the National Science Foundation Ice Core Facility, and Pennsylvania State University, and will utilize new and existing ice-core physical properties data from several previously drilled sites. This is a high-risk, low-cost project that could yield important results, and thus is well-suited for EAGER funding. This proposal utilizes existing ice cores and does not require Antarctic fieldwork. ", "east": -100.0, "geometry": "POINT(-107.5 -86.25)", "instruments": null, "is_usap_dc": true, "keywords": "Hercules Dome Ice Core; West Antarctica; Grain Statistics; LABORATORY; Ice Core; ICE SHEETS; Physical Properties; Brittle Ice; C-Axis Fabric; Bubble; ICE CORE RECORDS", "locations": "West Antarctica", "north": -85.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fegyveresi, John", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Hercules Dome Ice Core", "south": -87.0, "title": "EAGER: Constraining the Expected Brittle-ice Behavior for the Hercules Dome Ice-core Site.", "uid": "p0010378", "west": -115.0}, {"awards": "2025724 Harwood, David; 2026648 Tobin, Thomas; 2020728 Huber, Brian", "bounds_geometry": "POLYGON((-56.93 -64.2,-56.894 -64.2,-56.858 -64.2,-56.822 -64.2,-56.786 -64.2,-56.75 -64.2,-56.714 -64.2,-56.678 -64.2,-56.642 -64.2,-56.606 -64.2,-56.57 -64.2,-56.57 -64.214,-56.57 -64.22800000000001,-56.57 -64.242,-56.57 -64.256,-56.57 -64.27000000000001,-56.57 -64.284,-56.57 -64.298,-56.57 -64.312,-56.57 -64.32600000000001,-56.57 -64.34,-56.606 -64.34,-56.642 -64.34,-56.678 -64.34,-56.714 -64.34,-56.75 -64.34,-56.786 -64.34,-56.822 -64.34,-56.858 -64.34,-56.894 -64.34,-56.93 -64.34,-56.93 -64.32600000000001,-56.93 -64.312,-56.93 -64.298,-56.93 -64.284,-56.93 -64.27000000000001,-56.93 -64.256,-56.93 -64.242,-56.93 -64.22800000000001,-56.93 -64.214,-56.93 -64.2))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 15 Sep 2022 00:00:00 GMT", "description": "Non-technical description: \u003cbr/\u003eThis 4-year project is evaluating evidence of extinction patterns and depositional conditions from a high southern latitude Cretaceous-Paleogene (K-Pg) outcrop section found on Seymore Island, in the Western Antarctic Peninsula. The team is using sediment samples collected below the weathering horizon to evaluate detailed sedimentary structures, geochemistry, and microfossils in targeted stratigraphic intervals. The study will help determine if the K-Pg mass extinction was a single or double phased event and whether Seymour Island region in the geological past was a restricted, suboxic marine environment or an open well-mixed shelf. The award includes an integrated plan for student training at all levels, enhanced by a highlighted partnership with a high school earth sciences teacher working in a school serving underrepresented students.\u003cbr/\u003eTechnical description:\u003cbr/\u003e The proposed research is applying multiple techniques to address an overarching research question for which recent studies are in disagreement: Is the fossil evidence from a unique outcropping on Seymour Island, Antarctica consistent with a single or double phased extinction? In a two-phased model, the first extinction would affect primarily benthic organisms and would have occurred ~150 kiloyears prior to a separate extinction at the K-Pg boundary. However, this early extinction could plausibly be explained by an unrecognized facies control that is obscured by surficial weathering. This team is using microfossil evidence with detailed sedimentary petrology and geochemistry data to evaluate if the fossil evidence from Seymour Island is consistent with a single or double phased extinction process. The team is using detailed sedimentary petrology and geochemistry methods to test for facies changes across the K-PG interval that would explain the apparent early extinction. Samples of core sedimentary foraminifera, siliceous microfossils, and calcareous nannofossils are being evaluated to provide a high-resolution stratigraphic resolution and to evaluate whether evidence for an early extinction is present. Additionally, the team is using multiple geochemical methods to evaluate whether there is evidence for intermittent anoxia or euxinia and/or physical restriction of the Seymore region basin. Data from this analysis will indicate if this region was a restricted, suboxic marine environment or an open well-mixed shelf.", "east": -56.57, "geometry": "POINT(-56.75 -64.27000000000001)", "instruments": null, "is_usap_dc": true, "keywords": "Seymour Island; PALEOCLIMATE RECONSTRUCTIONS; SEDIMENTARY ROCKS; MICROFOSSILS; FIELD INVESTIGATION", "locations": "Seymour Island", "north": -64.2, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Tobin, Thomas; Totten, Rebecca", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": -64.34, "title": "Collaborative Research: Coring Seymour Island (CSI) Antarctica: Evaluating Causes and Effects of the End Cretaceous Mass Extinction", "uid": "p0010377", "west": -56.93}, {"awards": "1744562 Loose, Brice", "bounds_geometry": "POLYGON((-180 -71,-179.9 -71,-179.8 -71,-179.7 -71,-179.6 -71,-179.5 -71,-179.4 -71,-179.3 -71,-179.2 -71,-179.1 -71,-179 -71,-179 -71.7,-179 -72.4,-179 -73.1,-179 -73.8,-179 -74.5,-179 -75.2,-179 -75.9,-179 -76.6,-179 -77.3,-179 -78,-179.1 -78,-179.2 -78,-179.3 -78,-179.4 -78,-179.5 -78,-179.6 -78,-179.7 -78,-179.8 -78,-179.9 -78,180 -78,177.5 -78,175 -78,172.5 -78,170 -78,167.5 -78,165 -78,162.5 -78,160 -78,157.5 -78,155 -78,155 -77.3,155 -76.6,155 -75.9,155 -75.2,155 -74.5,155 -73.8,155 -73.1,155 -72.4,155 -71.7,155 -71,157.5 -71,160 -71,162.5 -71,165 -71,167.5 -71,170 -71,172.5 -71,175 -71,177.5 -71,-180 -71))", "dataset_titles": "Expedition Data of NBP1704; NBP1704 Expedition Data; PIPERS Noble Gases", "datasets": [{"dataset_uid": "601609", "doi": "10.15784/601609", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Mass Spectrometer; NBP1704; Noble Gas; Oceans; Ross Sea; R/v Nathaniel B. Palmer", "people": "Loose, Brice", "repository": "USAP-DC", "science_program": null, "title": "PIPERS Noble Gases", "url": "https://www.usap-dc.org/view/dataset/601609"}, {"dataset_uid": "200329", "doi": "", "keywords": null, "people": null, "repository": "MGDS", "science_program": null, "title": "Expedition Data of NBP1704", "url": "https://www.marine-geo.org/tools/entry/NBP1704"}, {"dataset_uid": "001363", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1704 Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1704"}], "date_created": "Wed, 14 Sep 2022 00:00:00 GMT", "description": "Near the Antarctic coast, polynyas are open-water regions where extreme heat loss in winter causes seawater to become cold, salty, and dense enough to sink into the deep sea. The formation of this dense water has regional and global importance because it influences the ocean current system. Polynya processes are also tied to the amount of sea ice formed, ocean heat lost to atmosphere, and atmospheric CO2 absorbed by the Southern Ocean. Unfortunately, the ocean-atmosphere interactions that influence the deep ocean water properties are difficult to observe directly during the Antarctic winter. This project will combine field measurements and laboratory experiments to investigate whether differences in the concentration of noble gasses (helium, neon, argon, xenon, and krypton) dissolved in ocean waters can be linked to environmental conditions at the time of their formation. If so, noble gas concentrations could provide insight into the mechanisms controlling shelf and bottom-water properties, and be used to reconstruct past climate conditions. Project results will contribute to the Southern Ocean Observing System (SOOS) theme of The Future and Consequences of Carbon Uptake in the Southern Ocean. The project will also train undergraduate and graduate students in environmental monitoring, and earth and ocean sciences methods. \u003cbr/\u003e\u003cbr/\u003eUnderstanding the causal links between Antarctic coastal processes and changes in the deep ocean system requires study of winter polynya processes. The winter period of intense ocean heat loss and sea ice production impacts two important Antarctic water masses: High-Salinity Shelf Water (HSSW), and Antarctic Bottom Water (AABW), which then influence the strength of the ocean solubility pump and meridional overturning circulation. To better characterize how sea ice cover, ocean-atmosphere exchange, brine rejection, and glacial melt influence the physical properties of AABW and HSSW, this project will analyze samples and data collected from two Ross Sea polynyas during the 2017 PIPERS winter cruise. Gas concentrations will be measured in seawater samples collected by a CTD rosette, from an underwater mass-spectrometer, and from a benchtop Membrane Inlet Mass Spectrometer. Noble gas concentrations will reveal the ocean-atmosphere (dis)equilibrium that exists at the time that surface water is transformed into HSSW and AABW, and provide a fingerprint of past conditions. In addition, nitrogen (N2), oxygen (O2), argon, and CO2 concentration will be used to determine the net metabolic balance, and to evaluate the efficacy of N2 as an alternative to O2 as glacial meltwater tracer. Laboratory experiments will determine the gas partitioning ratios during sea ice formation. Findings will be synthesized with PIPERS and related projects, and so provide an integrated view of the role of the wintertime Antarctic coastal system on deep water composition.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -179.0, "geometry": "POINT(168 -74.5)", "instruments": null, "is_usap_dc": true, "keywords": "Helium Isotopes; R/V NBP; DISSOLVED GASES; POLYNYAS; Ross Sea", "locations": "Ross Sea", "north": -71.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Loose, Brice", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "MGDS; R2R; USAP-DC", "science_programs": null, "south": -78.0, "title": "Measuring Dissolved Gases to Reveal the Processes that Drive the Solubility Pump and Determine Gas Concentration in Antarctic Bottom Water", "uid": "p0010376", "west": 155.0}, {"awards": "2146068 Kienle, Sarah", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 12 Sep 2022 00:00:00 GMT", "description": "The leopard seal (Hydrurga leptonyx) is an enigmatic apex predator in the rapidly changing Southern Ocean. As top predators, leopard seals play a disproportionately large role in ecosystem functioning; they also act as sentinel species that can track abiotic and biotic habitat changes. How leopard seals respond to a warming environment depends on their adaptive capacity\u2014a species\u2019 ability to cope with environmental change. However, leopard seals are one of the least studied apex predators on earth, hindering our ability to predict how the species is responding to polar environmental changes. Therefore, our objective is to determine leopard seals\u2019 adaptive capacity by quantifying their ability to move (dispersal ability), adapt (genetic diversity), and change (plasticity). In Aim 1, we will determine leopard seals\u2019 dispersal ability by assessing their distribution and movement patterns. In Aim 2, we will quantify genetic diversity by analyzing genetic variability and population structure. In Aim 3, we will examine plasticity by evaluating changes in their ecological niche and physiological responses. We have assembled an international, multidisciplinary Antarctic-experienced team to analyze existing data (e.g., photographs, census data, life history data, tissue samples, body morphometrics) collected from leopard seals across the Southern Ocean (e.g., South Shetland Islands, east and west Antarctica) over the last decade. Land- and cruise ship-based field efforts will generate comparable data from unsampled regions (e.g., Antarctic Peninsula, Chile, New Zealand,). By analyzing these historical and contemporary datasets, we will evaluate the adaptive capacity of leopard seals against the rapidly warming Southern Ocean. ", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; SPECIES/POPULATION INTERACTIONS; MARINE ECOSYSTEMS; MAMMALS; Southern Ocean", "locations": "Southern Ocean", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kienle, Sarah; Trumble, Stephen J; Bonin, Carolina", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "Move, Adapt, or Change: Examining the Adaptive Capacity of a Southern Ocean Apex Predator, the Leopard Seal", "uid": "p0010375", "west": null}, {"awards": "1853377 Shero, Michelle", "bounds_geometry": "POLYGON((162 -76,162.6 -76,163.2 -76,163.8 -76,164.4 -76,165 -76,165.6 -76,166.2 -76,166.8 -76,167.4 -76,168 -76,168 -76.2,168 -76.4,168 -76.6,168 -76.8,168 -77,168 -77.2,168 -77.4,168 -77.6,168 -77.8,168 -78,167.4 -78,166.8 -78,166.2 -78,165.6 -78,165 -78,164.4 -78,163.8 -78,163.2 -78,162.6 -78,162 -78,162 -77.8,162 -77.6,162 -77.4,162 -77.2,162 -77,162 -76.8,162 -76.6,162 -76.4,162 -76.2,162 -76))", "dataset_titles": "Weddell seal dive behavior and rhythmicity from 2010-2012 in the Ross Sea; Weddell seal iron dynamics and oxygen stores across lactation", "datasets": [{"dataset_uid": "601835", "doi": "10.15784/601835", "keywords": "Aerobic; Antarctica; Cryosphere; Weddell Seal", "people": "Shero, Michelle", "repository": "USAP-DC", "science_program": null, "title": "Weddell seal dive behavior and rhythmicity from 2010-2012 in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601835"}, {"dataset_uid": "601587", "doi": "10.15784/601587", "keywords": "Aerobic; Antarctica; Dive Capacity; Iron; McMurdo Sound; Weddell Seal", "people": "Shero, Michelle", "repository": "USAP-DC", "science_program": null, "title": "Weddell seal iron dynamics and oxygen stores across lactation", "url": "https://www.usap-dc.org/view/dataset/601587"}], "date_created": "Tue, 09 Aug 2022 00:00:00 GMT", "description": "Within any wild animal population there is substantial heterogeneity in reproductive rates and animal fitness. Not all individuals contribute to the population equally; some are able to produce more offspring than others and thus are considered to be of higher quality. This study aims to distinguish which physiological mechanisms (energy dynamics, aerobic capacity, and fertility) and underlying genetic factors make some Weddell seal females particularly successful at producing pups year after year, while others produce far fewer pups than the population average. In this project, an Organismal Energetics approach will identify key differences between high- and low-quality females in how they balance current and future reproductive success by tracking lactation costs, midsummer foraging success and pregnancy rates, and overwinter foraging patterns and live births the next year. Repeated sampling of individuals\u0027 physiological status (body composition, endocrinology, ovulation and pregnancy timing), will be paired with a whole-genome sequencing study. The second component of this study uses a Genome to Phenome approach to better understand how genetic differences between high- and low-quality females directly correspond to functional differences in transcription, translation, and ultimately phenotype. This component will contribute to the functional analysis and annotation of the Weddell seal genome. In combination, this project will make strides towards distinguishing the roles that plastic (physiological, behavioral) and fixed (genetic) factors play in complex, multifaceted traits such as fitness in a long-lived wild mammal. The project partners with established programs to implement extensive educational and outreach activities that will ensure wide dissemination to educators, students, and the public. It will contribute to a marine mammal exhibit at the Pink Palace Museum, and a PolarTREC science educator will participate in field work in Antarctica.", "east": 168.0, "geometry": "POINT(165 -77)", "instruments": null, "is_usap_dc": true, "keywords": "McMurdo; MAMMALS", "locations": "McMurdo", "north": -76.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Shero, Michelle; Hindle, Allyson; Burns, Jennifer; Briggs, Brandon", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Physiological and Genetic Correlates of Reproductive Success in High- versus Low-Quality Weddell seals", "uid": "p0010369", "west": 162.0}, {"awards": "1842542 Morgan, Daniel", "bounds_geometry": "POLYGON((160 -77,160.4 -77,160.8 -77,161.2 -77,161.6 -77,162 -77,162.4 -77,162.8 -77,163.2 -77,163.6 -77,164 -77,164 -77.1,164 -77.2,164 -77.3,164 -77.4,164 -77.5,164 -77.6,164 -77.7,164 -77.8,164 -77.9,164 -78,163.6 -78,163.2 -78,162.8 -78,162.4 -78,162 -78,161.6 -78,161.2 -78,160.8 -78,160.4 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 09 Aug 2022 00:00:00 GMT", "description": "The goal of this study is to identify and distinguish different source areas of glacial sediment in the McMurdo Dry Valleys, Antarctica to determine past glacial flow direction. Understanding ice flow is critical for determining how the Antarctic Ice Sheets have behaved in the past. Such insight is fundamental for allowing scientists to predict how the Antarctic Ice Sheets will evolve and, in turn, forecast how much and how fast sea level may rise. The project study site, the McMurdo Dry Valleys, contain a tremendous record of glacial deposits on land that extends back at least 14 million years. Chemistry of the rocks within the glacial deposits hold clues to the sources of ice that deposited the material. The chemical analyses of the glacial deposits will allow mapping of the former extent of glaciations providing a better understand of ice flow history. The mapping of the largest ice sheet expansion of the past 14 million years in the McMurdo Dry Valleys is of broad interest to the global climate change community. Undergraduate students comprise the majority of the field teams and will be responsible for sample preparation and analysis in the laboratory. \u003cbr/\u003e\u003cbr/\u003eThis project utilizes new geochemical techniques to test hypotheses about the source, extent, and flow patterns of the glacier ice that deposited glacial tills in the McMurdo Dry Valleys, Antarctica (MDV). The MDV contain an unparalleled terrestrial archive of glacial deposits, which record multiple sources of ice that deposited them. These include the northeast flowing ice that overrode the Transantarctic Mountains, the eastward expansion of the East Antarctic Ice Sheet, the westward extension of the Ross Ice Shelf representing an expansion of the West Antarctic Ice Sheet, and the growth of local alpine glaciers. The glacial tills and drifts in the Antarctic are typically isolated in patches or disjointed outcrop patterns making it difficult to correlate tills and determine their source. This project will undertake a systematic study of the tills in the McMurdo Dry Valleys to determine their provenance with a variety of geochemical techniques including major and minor element analyses with X-ray fluorescence, heavy mineral composition, soil salt concentration, and determining the uranium-lead (U-Pb) ages of zircon sands contained in these tills. The primary tool will be the age distribution of the population of detrital zircon in a glacial drift because it reflects the source of the tills and provides a unique geochemical \"fingerprint\" used to distinguish source areas while correlating units across different sites. A deliverable from this project will be a community available library of zircon fingerprints for mapped glacial tills from archived samples at the Polar Rock Repository and the systematic collection of samples in the MDV.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 164.0, "geometry": "POINT(162 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIATION; Dry Valleys", "locations": "Dry Valleys", "north": -77.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Morgan, Daniel", "platforms": null, "repositories": null, "science_programs": null, "south": -78.0, "title": "Unlocking the Glacial History of the McMurdo Dry Valleys, Antarctica by Fingerprinting Glacial Tills with Detrital Zircon U-Pb Age Populations", "uid": "p0010368", "west": 160.0}, {"awards": "2205008 Walker, Catherine", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Sun, 07 Aug 2022 00:00:00 GMT", "description": "The majority of mass loss from the Antarctic Ice Sheet, a major contributor to sea level rise, occurs at its margins, where ice meets the ocean. Glaciers and ice streams flow towards the coast and can go afloat over the water, forming ice shelves. Ice shelves make up almost half of the entire Antarctic coastline, and hold back the flow of inland ice in Antarctica continent; thus they are integral to the overall stability of the Antarctic Ice Sheet. Ice shelves lose mass by two main processes: iceberg calving and basal melting. Temporal and spatial fluctuations in both are driven by various processes; a major driver of ice shelf melt is the heat provided by the neighboring Southern Ocean. Ocean heat, in turn, is driven by various aspects of the ice shelf environment. One of the most significant contributors to changes in the ocean\u2019s heat content is the presence of sea ice. This research will focus on the effects of coastal polynyas (areas of open water amidst sea ice), how they modulate the local ocean environment, and how that environment drives ice shelf basal melting. To date, the relationship between polynyas and ice shelf melt has not been characterized on an Antarctic-wide scale. Understanding the feedbacks between polynya size and duration, ocean stratification, and ice shelf melt, and the strength of those feedbacks, will improve the ability to characterize influences on the long-term stability of ice shelves, and in turn, the Antarctic Ice Sheet as a whole. A critical aspect of this study is that it will provide a framework for understanding ice shelf-ocean interaction across a diverse range of geographic settings. This, together with improvements of various models, will help interpret the impacts of future climate change on these systems, as their responses are likely quite variable and, on the whole, different from the large-scale response of the ice sheet. This project will also provide a broader context to better design future observational studies of specific coastal polynya and ice shelf processes.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "United States Of America; ICE EXTENT; GLACIERS/ICE SHEETS", "locations": "United States Of America", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Walker, Catherine; Zhang, Weifeng; Seroussi, Helene", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Investigating the Role of Coastal Polynya Variability in Modulating Antarctic Marine-Terminating Glacier Drawdown", "uid": "p0010364", "west": -180.0}, {"awards": "2149518 Fudge, Tyler", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Sun, 07 Aug 2022 00:00:00 GMT", "description": "Interpreting highly compressed portions of ice cores is increasingly important as projects target climate records in basal ice, and in ice recovered from blue-ice areas. This project will integrate precisely co-registered electrical conductivity measurements (ECM), hyperspectral imaging, laser ablation ICPMS measurements of impurities, and ice physical properties to investigate sub-cm chemical and physical variations in polar ice. This work will establish to what extent annual layer interpretations of polar ice with sub-cm layering is possible. Critical to resolving thin ice layers is understanding the across-core variations which may obscure or distort the vertical layering. Analyses will be focused on samples from WAIS Divide, SPICEcore, and GISP2, which have well established seasonal cycles that yielded benchmark timescales, as well a large diameter ice core from a blue ice area.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "ICE CORE RECORDS; Ice Core", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fudge, T. J.; Fegyveresi, John M", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections", "uid": "p0010365", "west": -180.0}, {"awards": "2212904 Herbert, Lisa", "bounds_geometry": "POLYGON((-120 -71,-118 -71,-116 -71,-114 -71,-112 -71,-110 -71,-108 -71,-106 -71,-104 -71,-102 -71,-100 -71,-100 -71.4,-100 -71.8,-100 -72.2,-100 -72.6,-100 -73,-100 -73.4,-100 -73.8,-100 -74.2,-100 -74.6,-100 -75,-102 -75,-104 -75,-106 -75,-108 -75,-110 -75,-112 -75,-114 -75,-116 -75,-118 -75,-120 -75,-120 -74.6,-120 -74.2,-120 -73.8,-120 -73.4,-120 -73,-120 -72.6,-120 -72.2,-120 -71.8,-120 -71.4,-120 -71))", "dataset_titles": null, "datasets": null, "date_created": "Sun, 07 Aug 2022 00:00:00 GMT", "description": "The Amundsen Sea, near the fastest melting Antarctic glaciers, hosts one of the most productive polar ecosystems in the world. Phytoplankton serve as the base of the food chain, and their growth also removes carbon dioxide from the atmosphere. Phytoplankton growth is fertilized in this area by nutrient iron (Fe), which is only present at low concentrations in seawater. Prior studies have shown the seabed sediments may provide Fe to the Amundsen Sea ecosystem. However, sediment sources of Fe have never been studied here directly. This project fills this gap by analyzing sediments from the Amundsen Sea and investigating whether sediment Fe fertilizes plankton growth. The results will help scientists understand the basic ecosystem drivers and predict the effects of climate change on this vibrant, vulnerable region. This project also emphasizes inclusivity and openness to the public. The researchers will establish a mentoring network for diverse polar scientists through the Polar Impact Network and communicate their results to the public through CryoConnect.org. \r\n\r\nThis project leverages samples already collected from the Amundsen Sea (NBP22-02) to investigate sediment Fe cycling and fluxes. The broad questions driving this research are 1) does benthic Fe fertilize Antarctic coastal primary productivity, and 2) what are the feedbacks between benthic Fe release and carbon cycling in the coastal Antarctic? To answer these questions, the researchers will analyze pore water Fe content and speciation and calculate fluxes of Fe across the sediment-water interface. These results will be compared to sediment characteristics (e.g., organic carbon content, reactive Fe content, proximity to glacial sources) to identify controls on benthic Fe release. This research dovetails with and expands on the science goals of the \u201cAccelerating Thwaites Ecosystem Impacts for the Southern Ocean\u201d (ARTEMIS) project through which the field samples were collected. In turn, the findings of ARTEMIS regarding modeled and observed trace metal dynamics, surface water productivity, and carbon cycling will inform the conclusions of this project, allowing insight into the impact of benthic Fe in the whole system. This project represents a unique opportunity for combined study of the water column and sediment biogeochemistry which will be of great value to the marine biogeochemistry community and will inform future sediment-ocean studies in polar oceanography and beyond. \r\n", "east": -100.0, "geometry": "POINT(-110 -73)", "instruments": null, "is_usap_dc": true, "keywords": "TRACE ELEMENTS; SEDIMENT CHEMISTRY; Amundsen Sea", "locations": "Amundsen Sea", "north": -71.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Post Doc/Travel", "paleo_time": null, "persons": "Herbert, Lisa", "platforms": null, "repositories": null, "science_programs": null, "south": -75.0, "title": "OPP-PRF: Benthic Iron Fluxes and Cycling in the Amundsen Sea", "uid": "p0010362", "west": -120.0}, {"awards": "1640481 Rotella, Jay; 2147553 Rotella, Jay; 2147554 Chen, Nancy", "bounds_geometry": "POLYGON((162 -74.95,162.8 -74.95,163.6 -74.95,164.4 -74.95,165.2 -74.95,166 -74.95,166.8 -74.95,167.6 -74.95,168.4 -74.95,169.2 -74.95,170 -74.95,170 -75.295,170 -75.64,170 -75.985,170 -76.33,170 -76.67500000000001,170 -77.02000000000001,170 -77.36500000000001,170 -77.71000000000001,170 -78.055,170 -78.4,169.2 -78.4,168.4 -78.4,167.6 -78.4,166.8 -78.4,166 -78.4,165.2 -78.4,164.4 -78.4,163.6 -78.4,162.8 -78.4,162 -78.4,162 -78.055,162 -77.71000000000001,162 -77.36500000000001,162 -77.02000000000001,162 -76.67500000000001,162 -76.33,162 -75.985,162 -75.64,162 -75.295,162 -74.95))", "dataset_titles": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2023 Antarctic field season", "datasets": [{"dataset_uid": "601837", "doi": null, "keywords": "AMD; Amd/Us; Antarctica; Cryosphere; McMurdo Sound; Population Dynamics; USA/NSF; USAP-DC; Weddell Seal", "people": "Rotella, Jay", "repository": "USAP-DC", "science_program": null, "title": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2023 Antarctic field season", "url": "https://www.usap-dc.org/view/dataset/601837"}], "date_created": "Sun, 07 Aug 2022 00:00:00 GMT", "description": "Reliable predictions are needed for how populations of wild species, especially those at high latitudes, will respond to future environmental conditions. This study will use a strategic extension of the long-term demographic research program that has been conducted annually on the Erebus Bay population of Weddell seals since 1978 to help meet that need. Recent analyses of the study population indicate strong annual variation in reproduction, abundance, and population composition. The number of new immigrant mothers that join the population each year has recently grown such that most new mothers are now immigrants. Despite the growing number of immigrants, the demographic importance and geographic origins of immigrants are unknown. The research will (1) add new information on drivers of annual variation in immigrant numbers, (2) compare and combine information on the vital rates and demographic role of immigrant females and their offspring with that of locally born females, and (3) add genomic analyses that will quantify levels of genetic variation in and gene flow among the study population and other populations in the Ross Sea. The project will continue the long-term monitoring of the population at Erebus Bay and characterize population dynamics and the role of immigration using a combination of mark-recapture analyses, stochastic population modeling, and genomic analyses. The study will continue to (1) provide detailed data on individual seals to other science teams, (2) educate and mentor individuals in the next generation of ecologists, (3) introduce two early-career, female scientists to Antarctic research, and (4) add genomics approaches to the long-term population study of Erebus Bay Weddell seals. The Informal Science Education program will expand on the project\u2019s recent and successful efforts by producing and delivering short-form videos through an interactive web portal and diverse social-media technologies. The Informal Science Education program will continue to update and add new topics to a multimedia-enhanced electronic book about the project\u2019s research on Weddell seals that will be freely available to the public. The outreach efforts will increase the length of the book from ~140 to ~225 pages and add new topics such as learning about seals using genomics and how seals respond to a changing world.", "east": 170.0, "geometry": "POINT(166 -76.67500000000001)", "instruments": null, "is_usap_dc": true, "keywords": "SPECIES/POPULATION INTERACTIONS; McMurdo Sound", "locations": "McMurdo Sound", "north": -74.95, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rotella, Jay; Chen, Nancy", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.4, "title": "Collaborative Research: The Drivers and Role of Immigration in the Dynamics of the Largest Population of Weddell Seals in Antarctica under Changing Conditions", "uid": "p0010361", "west": 162.0}, {"awards": "1744767 Sanders, Robert", "bounds_geometry": "POLYGON((-68 -64,-67.4 -64,-66.8 -64,-66.2 -64,-65.6 -64,-65 -64,-64.4 -64,-63.8 -64,-63.2 -64,-62.6 -64,-62 -64,-62 -64.5,-62 -65,-62 -65.5,-62 -66,-62 -66.5,-62 -67,-62 -67.5,-62 -68,-62 -68.5,-62 -69,-62.6 -69,-63.2 -69,-63.8 -69,-64.4 -69,-65 -69,-65.6 -69,-66.2 -69,-66.8 -69,-67.4 -69,-68 -69,-68 -68.5,-68 -68,-68 -67.5,-68 -67,-68 -66.5,-68 -66,-68 -65.5,-68 -65,-68 -64.5,-68 -64))", "dataset_titles": "Companion datasets to Diversity of microbial eukaryotes along the West Antarctic peninsula in austral spring.; Expedition Data of NBP1910; Expedition Data of NBP 2205; LMG1904 expedition data; NBP1910_protist_community_RNA Raw sequence reads; NBP2205_protist_community_RNA Raw sequence reads will be made available here after processing is completed", "datasets": [{"dataset_uid": "200365", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "NBP1910_protist_community_RNA Raw sequence reads; NBP2205_protist_community_RNA Raw sequence reads will be made available here after processing is completed", "url": "https://www.ncbi.nlm.nih.gov/search/all/?term=PRJNA807326"}, {"dataset_uid": "200366", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP 2205", "url": "https://www.rvdata.us/search/cruise/NBP2205"}, {"dataset_uid": "200325", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1910", "url": "https://www.rvdata.us/search/cruise/NBP1910"}, {"dataset_uid": "200147", "doi": "10.7284/908260", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "LMG1904 expedition data", "url": "https://www.rvdata.us/search/cruise/LMG1904"}, {"dataset_uid": "200320", "doi": "10.6084/m9.figshare.19514110.v3", "keywords": null, "people": null, "repository": "Figshare", "science_program": null, "title": "Companion datasets to Diversity of microbial eukaryotes along the West Antarctic peninsula in austral spring.", "url": "https://doi.org/10.6084/m9.figshare.19514110.v3"}], "date_created": "Wed, 27 Jul 2022 00:00:00 GMT", "description": "Traditional models of oceanic food chains have consisted of photosynthetic algae (phytoplankton) being ingested by small animals (zooplankton), which were ingested by larger animals (fish). These traditional models changed as new methods allowed recognition of the importance of bacteria and other non-photosynthetic protozoa in more complex food webs. More recently, the wide-spread existence of mixotrophs (organisms that can both photosynthesize and ingest food particles) and their importance as microbial predators has been recognized in many oceanographic areas. In the Southern Ocean, the only two surveys of mixotrophs have suggested that there may be seasonal differences in their importance as predators. During the long polar night (winter), the ability of mixotrophs to ingest particulate food may aid in their survival thus ensuring a sufficient population in spring to support a phytoplankton bloom once photosynthesis rates can increase. Thus mixotrophs may provide a critical early food source upon which zooplankton and larger animals depend on for growth and reproduction. This project will advance understanding of mixotroph diversity and their ecological impact within the Southern Ocean microbial food web. Specifically, efforts will be focused on mixotrophy in the western Antarctica peninsula region during the austral spring and autumn when there are likely to be changes in the relative importance of photosynthesis and ingestion to mixotrophs. The project will provide research opportunities for undergraduate and graduate students and a post-doctoral researcher. There will be real-time outreach from the Southern Ocean to the public via blogs and interviews, and to high school art students through an established program that blends science and art education. Despite traditional views of protists as either \"phototrophic\" or \"heterotrophic,\" there are many photosynthetic protists that consume prey (mixotrophy). Mixotrophy is a widespread phenomenon in aquatic systems and phytoplankton groups with known mixotrophic species, notably chrysophytes, cryptophytes, prymnesiophytes, prasinophytes and dinoflagellates, are present and often abundant in Antarctic waters. However, in the Southern Ocean, the presence of mixotrophic phytoflagellates has been surveyed only twice prior to this project: in the Ross Sea during Austral spring 2008 and summer 2011. The primary goals of the project are to gain better understanding of mixotroph diversity and their ecological impact with respect to the Southern Ocean microbial food web. The contribution of mixotrophs to primary production and bacterial consumption is likely linked to the taxonomic composition of the community and the abundance of particular species. Abundances of novel mixotrophic species will be evaluated via qPCR, which will be coupled with assessments of rates of feeding and photosynthesis with the goal of describing how active mixotrophs direct the movement of carbon through food webs. These experiments will help the determination of how viable and widespread mixotrophy is as a nutritional strategy in polar waters and give direct information on the currently unknown diversity of mixotrophic taxa under different environmental conditions occurring in austral spring and autumn. Furthermore, the methods will simultaneously yield information on the whole communities of protists - mixotrophic, phototrophic and heterotrophic. In addition, a method to examine aspects of the taxonomic and functional diversities of the bacterivorous/mixotrophic community will be employed. A thymidine analog (BrdU) will be used to label DNA of eukaryotes feeding on bacteria. The BrdU-labeled eukaryotic DNA will be isolated using immunoprecipitation. High-throughput sequencing of the labeled DNA (bacterivores) versus unlabeled community DNA will determine the diversity of bacterivorous mixotrophs relative to other microeukaryotes. Flow cytometric sorting based on chlorophyll to focus on mixotrophic species. These approaches will elucidate a gap in current knowledge of the influence of microbial interactions in the Southern Ocean under different conditions. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -62.0, "geometry": "POINT(-65 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; PLANKTON; COASTAL", "locations": "Antarctic Peninsula", "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Sanders, Robert; Gast, Rebecca; Jeffrey, Wade H.", "platforms": null, "repo": "NCBI", "repositories": "Figshare; NCBI; R2R", "science_programs": null, "south": -69.0, "title": "Collaborative Research: Diversity and ecological impacts of Antarctic mixotrophic phytoplankton", "uid": "p0010357", "west": -68.0}, {"awards": "2138277 Gallagher, Katherine", "bounds_geometry": "POLYGON((-78 -62,-76.2 -62,-74.4 -62,-72.6 -62,-70.8 -62,-69 -62,-67.2 -62,-65.4 -62,-63.6 -62,-61.8 -62,-60 -62,-60 -63,-60 -64,-60 -65,-60 -66,-60 -67,-60 -68,-60 -69,-60 -70,-60 -71,-60 -72,-61.8 -72,-63.6 -72,-65.4 -72,-67.2 -72,-69 -72,-70.8 -72,-72.6 -72,-74.4 -72,-76.2 -72,-78 -72,-78 -71,-78 -70,-78 -69,-78 -68,-78 -67,-78 -66,-78 -65,-78 -64,-78 -63,-78 -62))", "dataset_titles": "Current velocity and direction data from Regional Ocean Modeling System simulations (2006-2007 \u0026 2010-2011); Current velocity and direction data from Regional Ocean Modeling System simulations (2008-2009 \u0026 2018-2019); Passive particle trajectories from Regional Ocean Modeling System simulations 2008-2009 \u0026 2018-2019; Simulated krill trajectory data from Regional Ocean Modeling System simulations 2006-2007 \u0026 2010-2011; Simulated krill trajectory data from Regional Ocean Modeling System simulations 2008-2009 \u0026 2018-2019; Simulated marine debris trajectories along the West Antarctic Peninsula in 2008-2009 and 2018-2019", "datasets": [{"dataset_uid": "601656", "doi": "10.15784/601656", "keywords": "Antarctica; Model Data; Ocean Currents; Physical Oceanography; Regional Ocean Modeling System; ROMS; West Antarctic Shelf", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Current velocity and direction data from Regional Ocean Modeling System simulations (2008-2009 \u0026 2018-2019)", "url": "https://www.usap-dc.org/view/dataset/601656"}, {"dataset_uid": "601682", "doi": "10.15784/601682", "keywords": "Antarctica; Physical Oceanography; Regional Ocean Modeling System; ROMS", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Passive particle trajectories from Regional Ocean Modeling System simulations 2008-2009 \u0026 2018-2019", "url": "https://www.usap-dc.org/view/dataset/601682"}, {"dataset_uid": "601734", "doi": "10.15784/601734", "keywords": "Antarctica; Modeling; Regional Ocean Modeling System; West Antarctic Shelf", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Simulated marine debris trajectories along the West Antarctic Peninsula in 2008-2009 and 2018-2019", "url": "https://www.usap-dc.org/view/dataset/601734"}, {"dataset_uid": "601780", "doi": "10.15784/601780", "keywords": "Antarctica; Antarctic Krill; Cryosphere; Model Data; Physical Oceanography; Regional Ocean Modeling System; ROMS; West Antarctic Shelf", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Simulated krill trajectory data from Regional Ocean Modeling System simulations 2006-2007 \u0026 2010-2011", "url": "https://www.usap-dc.org/view/dataset/601780"}, {"dataset_uid": "601779", "doi": "10.15784/601779", "keywords": "Antarctica; Cryosphere; Model Data; Ocean Currents; Physical Oceanography; Regional Ocean Modeling System; ROMS; West Antarctic Shelf", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Current velocity and direction data from Regional Ocean Modeling System simulations (2006-2007 \u0026 2010-2011)", "url": "https://www.usap-dc.org/view/dataset/601779"}, {"dataset_uid": "601655", "doi": "10.15784/601655", "keywords": "Antarctica; Antarctic Krill; Model Data; Physical Oceanography; Regional Ocean Modeling System; ROMS; West Antarctic Shelf", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Simulated krill trajectory data from Regional Ocean Modeling System simulations 2008-2009 \u0026 2018-2019", "url": "https://www.usap-dc.org/view/dataset/601655"}], "date_created": "Tue, 19 Jul 2022 00:00:00 GMT", "description": "Pygoscelis penguins are central place foragers during the summer while they raise their chicks. They leave and return to the same colony location after hunting for food and rely on the availability of Antarctic krill, their primary food source. This research focuses on whether penguin diets and colony location reflect the retention of prey around and near colonies on the West Antarctic Peninsula. Eddies and other oceanographic processes may facilitate prey retention at certain locations, driving penguin colony establishment and success. \r\n\r\nThis project hypothesizes that Pygoscelis penguin diets will be composed of more Antarctic krill (Euphausia superba) when local prey retention is high, possibly due to subsurface eddies. This hypothesis will be tested using satellite-based estimates of Pygoscelis penguin diet composition using multispectral sensor data to estimate nitrogen values and infer trophic level. Prey retention will be calculated along the peninsula using the Regional Ocean Modeling System (ROMS). Simulated particles and diel vertical migration will be used to mimic krill behavior. These particles can be experimentally seeded across multiple depths in multiple years to assess residence times in the system. Using penguin colony data from the Mapping Application for Penguin Populations and Projected Dynamics (MAPPPD), the PI will correlate diet and retention metrics to local penguin colony growth and persistence and build a predictive model of where colonies may form in the future.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -60.0, "geometry": "POINT(-69 -67)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; PENGUINS; SPECIES/POPULATION INTERACTIONS; OCEAN CURRENTS", "locations": "Antarctic Peninsula", "north": -62.0, "nsf_funding_programs": "Post Doc/Travel", "paleo_time": null, "persons": "Gallagher, Katherine", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.0, "title": "OPP-PRF Pygoscelis Penguin Response to Potential Prey Retention along the West Antarctic Peninsula", "uid": "p0010349", "west": -78.0}, {"awards": "1947657 Dodd, Justin; 1947558 Leckie, Robert; 1947646 Shevenell, Amelia", "bounds_geometry": "POLYGON((-180 -72.5,-177.6 -72.5,-175.2 -72.5,-172.8 -72.5,-170.4 -72.5,-168 -72.5,-165.6 -72.5,-163.2 -72.5,-160.8 -72.5,-158.4 -72.5,-156 -72.5,-156 -73.15,-156 -73.8,-156 -74.45,-156 -75.1,-156 -75.75,-156 -76.4,-156 -77.05,-156 -77.7,-156 -78.35,-156 -79,-158.4 -79,-160.8 -79,-163.2 -79,-165.6 -79,-168 -79,-170.4 -79,-172.8 -79,-175.2 -79,-177.6 -79,180 -79,178.4 -79,176.8 -79,175.2 -79,173.6 -79,172 -79,170.4 -79,168.8 -79,167.2 -79,165.6 -79,164 -79,164 -78.35,164 -77.7,164 -77.05,164 -76.4,164 -75.75,164 -75.1,164 -74.45,164 -73.8,164 -73.15,164 -72.5,165.6 -72.5,167.2 -72.5,168.8 -72.5,170.4 -72.5,172 -72.5,173.6 -72.5,175.2 -72.5,176.8 -72.5,178.4 -72.5,-180 -72.5))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 08 Jun 2022 00:00:00 GMT", "description": "Presently, Antarctica\u0027s glaciers are melting as Earth\u0027s atmosphere and the Southern Ocean warm. Not much is known about how Antarctica\u0027s ice sheets might respond to ongoing and future warming, but such knowledge is important because Antarctica\u0027s ice sheets might raise global sea levels significantly with continued melting. Over time, mud accumulates on the sea floor around Antarctica that is composed of the skeletons and debris of microscopic marine organisms and sediment from the adjacent continent. As this mud is deposited, it creates a record of past environmental and ecological changes, including ocean depth, glacier advance and retreat, ocean temperature, ocean circulation, marine ecosystems, ocean chemistry, and continental weathering. Scientists interested in understanding how Antarctica\u0027s glaciers and ice sheets might respond to ongoing warming can use a variety of physical, biological, and chemical analyses of these mud archives to determine how long ago the mud was deposited and how the ice sheets, oceans, and marine ecosystems responded during intervals in the past when Earth\u0027s climate was warmer. In this project, researchers from the University of South Florida, University of Massachusetts, and Northern Illinois University will reconstruct the depth, ocean temperature, weathering and nutrient input, and marine ecosystems in the central Ross Sea from ~17 to 13 million years ago, when the warm Miocene Climate Optimum transitioned to a cooler interval with more extensive ice sheets. Record will be generated from new sediments recovered during the International Ocean Discovery Program (IODP) Expedition 374 and legacy sequences recovered in the 1970?s during the Deep Sea Drilling Program. Results will be integrated into ice sheet and climate models to improve the accuracy of predictions. ", "east": -156.0, "geometry": "POINT(-176 -75.75)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; LABORATORY; AMD; PALEOCLIMATE RECONSTRUCTIONS; Ross Sea; USAP-DC; USA/NSF", "locations": "Ross Sea", "north": -72.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Shevenell, Amelia", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -79.0, "title": "Collaborative Proposal: Miocene Climate Extremes: A Ross Sea Perspective from IODP Expedition 374 and DSDP Leg 28 Marine Sediments", "uid": "p0010335", "west": 164.0}, {"awards": "1951090 Stukel, Michael", "bounds_geometry": "POLYGON((-80 -63,-78.2 -63,-76.4 -63,-74.6 -63,-72.8 -63,-71 -63,-69.2 -63,-67.4 -63,-65.6 -63,-63.8 -63,-62 -63,-62 -63.7,-62 -64.4,-62 -65.1,-62 -65.8,-62 -66.5,-62 -67.2,-62 -67.9,-62 -68.6,-62 -69.3,-62 -70,-63.8 -70,-65.6 -70,-67.4 -70,-69.2 -70,-71 -70,-72.8 -70,-74.6 -70,-76.4 -70,-78.2 -70,-80 -70,-80 -69.3,-80 -68.6,-80 -67.9,-80 -67.2,-80 -66.5,-80 -65.8,-80 -65.1,-80 -64.4,-80 -63.7,-80 -63))", "dataset_titles": "BCO-DMO Project Page", "datasets": [{"dataset_uid": "200294", "doi": null, "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "BCO-DMO Project Page", "url": "https://www.bco-dmo.org/project/838048"}], "date_created": "Fri, 03 Jun 2022 00:00:00 GMT", "description": "Algae in the surface ocean convert carbon dioxide into organic carbon through photosynthesis. The biological carbon pump transports this organic carbon from the atmosphere to the deep ocean where it can be stored for tens to hundreds of years. Annually, the amount transported is similar to that humans are currently emitting by burning fossil fuels. However, at present we cannot predict how this important process will change with a warming ocean. These investigators plan to develop a 15+ year time-series of vertical carbon transfer for the Western Antarctic Peninsula; a highly productive Antarctic ecosystem. This region is also rapid transition to warmer temperatures leading to reduced sea ice coverage. This work will help researchers better understand how the carbon cycle in the Western Antarctic Peninsula will respond to climate change. The researchers will develop the first large-scale time-series of carbon flux anywhere in the ocean. This research will also support the education and training of a graduate student and support the integration of concepts in Antarctic research into two undergraduate courses designed for non-science majors and advanced earth science students. The researchers will also develop educational modules for introducing elementary and middle-school age students to important concepts such as gross and net primary productivity, feedbacks in the marine and atmospheric systems, and the differences between correlation and causation. Results from this proposal will also be incorporated into a children?s book, ?Plankton do the Strangest Things?, that is targeted at 5-7 year olds and is designed to introduce them to the incredible diversity and fascinating adaptations of microscopic marine organisms.\u003cbr/\u003e\u003cbr/\u003e This research seeks to leverage 6 years (2015-2020) of 234Th samples collected on Palmer LTER program, 5 years of prior measurements (2009-2010, 2012-2014), and upcoming cruises (2021-2023) to develop a time-series of summertime particle flux in the WAP that stretches for 15 years. The 238U-234Th disequilibrium approach utilizes changes in the activity of the particle-active radio-isotope 234Th relative to its parent nuclide 238U to quantify the flux of sinking carbon out of the surface ocean (over a time-scale of ~one month). This proposal will fund 234Th analyses from nine years? worth of cruises (2015-2023) and extensive analyses designed to investigate the processes driving inter-annual variability in the BCP. These include: 1) physical modeling to quantify the importance of advection and diffusion in the 234Th budget, 2) time-series analyses of particle flux, and 3) statistical modeling of the relationships between particle flux and multiple presumed drivers (biological, chemical, physical, and climate indices) measured by collaborators in the Palmer LTER program. This multi-faceted approach is critical for linking the measurements to models and for predicting responses to climate change. It will also test the hypothesis that export flux is decreasing in the northern WAP, increasing in the southern WAP, and increasing when integrated over the entire region as a result of earlier sea ice retreat and a larger ice-free zone. The project will also investigate relationships between carbon export and multiple potentially controlling factors including: primary productivity, algal biomass and taxonomic composition, biological oxygen saturation, zooplankton biomass and taxonomic composition, bacterial production, temperature, wintertime sea ice extent, date of sea ice retreat, and climate modes.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -62.0, "geometry": "POINT(-71 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; AMD; FIELD INVESTIGATION; Palmer Station; USAP-DC; BIOGEOCHEMICAL CYCLES; USA/NSF", "locations": "Palmer Station", "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Stukel, Michael", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -70.0, "title": "Quantifying Processes Driving Interannual Variability in the Biological Carbon Pump in the Western Antarctic Peninsula", "uid": "p0010332", "west": -80.0}, {"awards": "2055455 Duhaime, Melissa", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 03 Jun 2022 00:00:00 GMT", "description": "Part 1: Non-technical description:\r\nIt is well known that the Southern Ocean plays an important role in global carbon cycling and also receives a disproportionately large influence of climate change. The role of marine viruses on ocean productivity is largely understudied, especially in this global region. This team proposes to use combination of genomics, flow cytometry, and network modeling to test the hypothesis that viral biogeography, infection networks, and viral impacts on microbial metabolism can explain variations in net community production (NCP) and carbon cycling in the Southern Ocean. The project includes the training of a postdoctoral scholar, graduate students and undergraduate students. It also includes the development of a new Polar Sci ReachOut program in partnership with the University of Michigan Museum of Natural History especially targeted to middle-school students and teachers and the general public. The team will also produce a Science for Tomorrow (SFT) program for use in middle schools in metro-Detroit communities and lead a summer Research Experience for Teachers (RET) fellows. \r\n\r\nPart 2: Technical description: \r\nThe study will leverage hundreds of existing samples collected for microbes and viruses from the Antarctic Circumpolar Expedition (ACE). These samples provide the first contiguous survey of viral diversity and microbial communities around Antarctica. Viral networks are being studied in the context of biogeochemical data to model community networks and predict net community production (NCP), which will provide a way to evaluate the role of viruses in Southern Ocean carbon cycling. Using cutting edge molecular and flow cytometry approaches, this project addresses the following questions: 1) How/why are Southern Ocean viral populations distributed across environmental gradients? 2a) Do viruses interfere with \"keystone\" metabolic pathways and biogeochemical processes of microbial communities in the Southern Ocean? 2b) Does nutrient availability or other environmental variables drive changes in virus-microbe infection networks in the Southern Ocean? Results will be used to develop and evaluate generative models of NCP predictions that incorporate the importance of viral traits and virus-host interactions.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; Amd/Us; AMD; FIELD INVESTIGATION; USA/NSF; AQUATIC SCIENCES; BACTERIA/ARCHAEA; MARINE ECOSYSTEMS; VIRUSES; USAP-DC", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Duhaime, Melissa; Zaman, Luis", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": -90.0, "title": "ANT LIA - Viral Ecogenomics of the Southern Ocean: Unifying Omics and Ecological Networks to Advance our Understanding of Antarctic Microbial Ecosystem Function", "uid": "p0010333", "west": -180.0}, {"awards": "1945127 Moffat, Carlos", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 03 Jun 2022 00:00:00 GMT", "description": "Freshwater discharges from melting high-latitude continental ice glacial reserves strongly control salt budgets, circulation and associated ocean water mass formation arising from polar ice shelves. These are different in nature than freshwater inputs associated with riverine coastal inputs. The PI proposes an observational deployment to measure a specific, previously-identified example of a coastal freshwater-driven current, the Antarctic Peninsula Coastal Current (APCC). \u003cbr/\u003e \u003cbr/\u003eThe research component of this CAREER project aims to improve understanding of the dynamics of freshwater discharge around the Antarctic continent. Associated research questions pertain to the i) controls on the cross- and along-shelf spreading of fresh, buoyant coastal currents, ii) the role of distributed coastal freshwater sources (as opposed to \u0027point\u0027 source river outflow sources typical of lower latitudes), and iii) the contribution of these coastal currents to water mass transformation and heat transfer on the continental shelf. An educational CAREER program component leverages a series of field experiences and research outputs including data, model outputs, and theory, to bring polar science to the classroom and the general public, as well as training a new polar scientist. This combined strategy will allow the investigator to lay the foundation for a successful academic career as a researcher and teacher at the University of Delaware. The project will also provide the opportunity to train a PhD student. Informal outreach efforts will include giving public lectures at University of Deleware\u0027s sponsored events, including Coast Day, a summer event that attracts 8000-10000 people, and remote lectures from the field using an existing outreach network. This proposal requires fieldwork in the Antarctic.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; R/V LMG; TURBULENCE; USAP-DC; OCEAN CURRENTS; Antarctic Peninsula; AMD; USA/NSF; HEAT FLUX", "locations": "Antarctic Peninsula", "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Moffat, Carlos", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repositories": null, "science_programs": null, "south": null, "title": "CAREER: The Transformation, Cross-shore Export, and along-shore Transport of Freshwater on Antarctic Shelves", "uid": "p0010330", "west": null}, {"awards": "2141555 Brooks, Cassandra", "bounds_geometry": "POLYGON((-180 -71.5,-177.1 -71.5,-174.2 -71.5,-171.3 -71.5,-168.4 -71.5,-165.5 -71.5,-162.6 -71.5,-159.7 -71.5,-156.8 -71.5,-153.9 -71.5,-151 -71.5,-151 -72.25,-151 -73,-151 -73.75,-151 -74.5,-151 -75.25,-151 -76,-151 -76.75,-151 -77.5,-151 -78.25,-151 -79,-153.9 -79,-156.8 -79,-159.7 -79,-162.6 -79,-165.5 -79,-168.4 -79,-171.3 -79,-174.2 -79,-177.1 -79,180 -79,178.1 -79,176.2 -79,174.3 -79,172.4 -79,170.5 -79,168.6 -79,166.7 -79,164.8 -79,162.9 -79,161 -79,161 -78.25,161 -77.5,161 -76.75,161 -76,161 -75.25,161 -74.5,161 -73.75,161 -73,161 -72.25,161 -71.5,162.9 -71.5,164.8 -71.5,166.7 -71.5,168.6 -71.5,170.5 -71.5,172.4 -71.5,174.3 -71.5,176.2 -71.5,178.1 -71.5,-180 -71.5))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 27 May 2022 00:00:00 GMT", "description": "The Ross Sea, Antarctica, is one of the last large intact marine ecosystems left in the world, yet is facing increasing pressure from commercial fisheries and environmental change. It is the most productive stretch of the Southern Ocean, supporting an array of marine life, including Antarctic toothfish the regions top fish predator. While a commercial fishery for toothfish continues to grow in the Ross Sea, fundamental knowledge gaps remain regarding toothfish ecology and the impacts of toothfish fishing on the broader Ross Sea ecosystem. Recognizing the global value of the Ross Sea, a large (\u003e2 million km2) marine protected area was adopted by the multi-national Commission for the Conservation of Antarctic Marine Living Resources in 2016. This research will fill a critical gap in the knowledge of Antarctic toothfish and deepen understanding of biological-physical interactions for fish ecology, while contributing to knowledge of impacts of fishing and environmental change on the Ross Sea system. This work will further provide innovative tools for studying connectivity among geographically distinct fish populations and for synthesizing and assessing the efficacy of a large-scale marine protected area. In developing an integrated research and education program in engaged scholarship, this project seeks to train the next generation of scholars to engage across the science-policy-public interface, engage with Southern Ocean stakeholders throughout the research process, and to deepen the publics appreciation of the Antarctic. \r\n\r\nA major research priority among Ross Sea scientists is to better understand the life history of the Antarctic toothfish and test the efficacy of the Ross Sea Marine Protected Area (MPA) in protecting against the impacts of overfishing and climate change. Like growth rings of a tree, fish ear bones, called otoliths, develop annual layers of calcium carbonate that incorporates elements from their environment. Otoliths offer information on the fishs growth and the surrounding ocean conditions. Hypothesizing that much of the Antarctic toothfish life cycle is structured by ocean circulation, this research employs a multi-disciplinary approach combining age and growth work with otolith chemistry testing, while also utilizing GIS mapping. The project will measure life history parameters as well as trace elements and stable isotopes in otoliths in three distinct sets collected over the last four decades in the Ross Sea. The information will be used to quantify the transport pathways Antarctic toothfish use across their life history, and across time, in the Ross Sea. The project will assess if toothfish populations from the Ross Sea are connected more widely across the Antarctic. By comparing life history and otolith chemistry data across time, the researchers will assess change in life history parameters and spatial dynamics and seek to infer if these changes are driven by fishing or climate change. Spatially mapping of these data will allow an assessment of the efficacy of the Ross Sea MPA in protecting toothfish and where further protections might be needed.\r\n\r\nThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": -151.0, "geometry": "POINT(-175 -75.25)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; USA/NSF; FIELD INVESTIGATION; USAP-DC; AMD; FISHERIES; Ross Sea", "locations": "Ross Sea", "north": -71.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Brooks, Cassandra", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": -79.0, "title": "CAREER: Using Otolith Chemistry to Reveal the Life History of Antarctic Toothfish in the Ross Sea, Antarctica: Testing Fisheries and Climate Change Impacts on a Top Fish Predator", "uid": "p0010329", "west": 161.0}, {"awards": "2019719 Brook, Edward", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "2019-2020 Allan Hills Field Report; 2022-23 Allan Hills Intermediate Ice Core Site Selection Field Report; 2022-23 (CXA1) flight based HDF5/matlab format data; 2022-23 (CXA1) transect based (science organized) unfocused data; 2023-2024 Allan Hills End-of-Season Science Report; 2023-24 (CXA2) flight based data HDF5/matlab format; 2023-24 (CXA2) transect based (science organized) unfocused data; Allan Hills 2022-23 Shallow Ice Core Field Report; Allan Hills I-188 Field Season Report 2022-2023; COLDEX Raw MARFA Ice Penetrating Radar data; Replicate O-17-excess by continuous flow laser spectroscopy for an ice core section at Summit, Greenland", "datasets": [{"dataset_uid": "601768", "doi": null, "keywords": "Antarctica; East Antarctic Plateau", "people": "Kempf, Scott D.; Ng, Gregory; Young, Duncan A.; Blankenship, Donald D.; Greenbaum, Jamin; Kerr, Megan; Chan, Kristian; Buhl, Dillon", "repository": "USAP-DC", "science_program": null, "title": "COLDEX Raw MARFA Ice Penetrating Radar data", "url": "https://www.usap-dc.org/view/dataset/601768"}, {"dataset_uid": "200405", "doi": "10.18738/T8/XPMLCC", "keywords": null, "people": null, "repository": "TDR", "science_program": null, "title": "2022-23 (CXA1) transect based (science organized) unfocused data", "url": "https://dataverse.tdl.org/dataset.xhtml?persistentId=doi:10.18738/T8/XPMLCC"}, {"dataset_uid": "601824", "doi": "10.15784/601824", "keywords": "Allan Hills; Antarctica; Coldex; Cryosphere", "people": "Hudak, Abigail; Banerjee, Asmita; Morton, Elizabeth; Jayred, Michael; Goverman, Ashley; Mayo, Emalia; Epifanio, Jenna; Shackleton, Sarah; Carter, Austin; Manos, John-Morgan; Marks Peterson, Julia; Higgins, John; Brook, Edward J.", "repository": "USAP-DC", "science_program": "COLDEX", "title": "2023-2024 Allan Hills End-of-Season Science Report", "url": "https://www.usap-dc.org/view/dataset/601824"}, {"dataset_uid": "200406", "doi": "10.18738/T8/FV6VNT", "keywords": null, "people": null, "repository": "TDR", "science_program": null, "title": "2023-24 (CXA2) transect based (science organized) unfocused data", "url": "https://dataverse.tdl.org/dataset.xhtml?persistentId=doi:10.18738/T8/FV6VNT"}, {"dataset_uid": "601826", "doi": "10.15784/601826", "keywords": "Allan Hills; Antarctica; Cryosphere", "people": "Shaya, Margot; Conway, Howard; Horlings, Annika; Epifanio, Jenna; Manos, John-Morgan", "repository": "USAP-DC", "science_program": "COLDEX", "title": "Allan Hills I-188 Field Season Report 2022-2023", "url": "https://www.usap-dc.org/view/dataset/601826"}, {"dataset_uid": "601697", "doi": "10.15784/601697", "keywords": "Allan Hills; Antarctica; Apres; Ice Core; Ice Penetrating Radar; Temperature Profiles", "people": "Brook, Edward J.; Conway, Howard", "repository": "USAP-DC", "science_program": "COLDEX", "title": "2022-23 Allan Hills Intermediate Ice Core Site Selection Field Report", "url": "https://www.usap-dc.org/view/dataset/601697"}, {"dataset_uid": "200404", "doi": "10.18738/T8/J38CO5", "keywords": null, "people": null, "repository": "OPR", "science_program": null, "title": "2023-24 (CXA2) flight based data HDF5/matlab format", "url": "https://data.cresis.ku.edu/data/rds/2023_Antarctica_BaslerMKB/"}, {"dataset_uid": "200403", "doi": "https://doi.org/10.18738/T8/J38CO5", "keywords": null, "people": null, "repository": "OPR", "science_program": null, "title": "2022-23 (CXA1) flight based HDF5/matlab format data", "url": "https://data.cresis.ku.edu/data/rds/2022_Antarctica_BaslerMKB/"}, {"dataset_uid": "601696", "doi": "10.15784/601696", "keywords": "Allan Hills; Antarctica; Ice Core", "people": "Shackleton, Sarah; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Allan Hills 2022-23 Shallow Ice Core Field Report", "url": "https://www.usap-dc.org/view/dataset/601696"}, {"dataset_uid": "601819", "doi": "10.15784/601819", "keywords": "Allan Hills; Antarctica; Cryosphere", "people": "Nesbitt, Ian; Carter, Austin; Epifanio, Jenna; Kuhl, Tanner; Morton, Elizabeth; Zajicek, Anna; Higgins, John; Shackleton, Sarah; Morgan, Jacob", "repository": "USAP-DC", "science_program": "COLDEX", "title": "2019-2020 Allan Hills Field Report", "url": "https://www.usap-dc.org/view/dataset/601819"}, {"dataset_uid": "601659", "doi": "10.15784/601659", "keywords": "Antarctica; Continuous Flow; Glaciology; Greenland; Ice Core Data; Laser Spectroscopy; Oxygen Isotope; Triple Oxygen Isotopes", "people": "Davidge, Lindsey", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "Replicate O-17-excess by continuous flow laser spectroscopy for an ice core section at Summit, Greenland", "url": "https://www.usap-dc.org/view/dataset/601659"}], "date_created": "Sat, 21 May 2022 00:00:00 GMT", "description": "Cores drilled through the Antarctic ice sheet provide a remarkable window on the evolution of Earth\u2019s climate and unique samples of the ancient atmosphere. The clear link between greenhouse gases and climate revealed by ice cores underpins much of the scientific understanding of climate change. Unfortunately, the existing data do not extend far enough back in time to reveal key features of climates warmer than today. COLDEX, the Center for Oldest Ice Exploration, will solve this problem by exploring Antarctica for sites to collect the oldest possible record of past climate recorded in the ice sheet. COLDEX will provide critical information for understanding how Earth\u2019s near-future climate may evolve and why climate varies over geologic time. New technologies will be developed for exploration and analysis that will have a long legacy for future research. An archive of old ice will stimulate new research for the next generations of polar scientists. COLDEX programs will galvanize that next generation of polar researchers, bring new results to other scientific disciplines and the public, and help to create a more inclusive and diverse scientific community.\r\n\r\nKnowledge of Earth\u2019s climate history is grounded in the geologic record. This knowledge is gained by measuring chemical, biological and physical properties of geologic materials that reflect elements of climate. Ice cores retrieved from polar ice sheets play a central role in this science and provide the best evidence for a strong link between atmospheric carbon dioxide and climate on geologic timescales. The goal of COLDEX is to extend the ice-core record of past climate to at least 1.5 million years by drilling and analyzing a continuous ice core in East Antarctica, and to much older times using discontinuous ice sections at the base and margin of the ice sheet. COLDEX will develop and deploy novel radar and melt-probe tools to rapidly explore the ice, use ice-sheet models to constrain where old ice is preserved, conduct ice coring, develop new analytical systems, and produce novel paleoclimate records from locations across East Antarctica. The search for Earth\u2019s oldest ice also provides a compelling narrative for disseminating information about past and future climate change and polar science to students, teachers, the media, policy makers and the public. COLDEX will engage and incorporate these groups through targeted professional development workshops, undergraduate research experiences, a comprehensive communication program, annual scientific meetings, scholarships, and broad collaboration nationally and internationally. COLDEX will provide a focal point for efforts to increase diversity in polar science by providing field, laboratory, mentoring and networking experiences for students and early career scientists from groups underrepresented in STEM, and by continuous engagement of the entire COLDEX community in developing a more inclusive scientific culture.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; AMD; Antarctica; Amd/Us; Coldex; USAP-DC; FIELD SURVEYS; ICE DEPTH/THICKNESS", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Polar Special Initiatives; Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward J.; Neff, Peter", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "OPR; TDR; USAP-DC", "science_programs": "COLDEX", "south": -90.0, "title": "Center for Oldest Ice Exploration", "uid": "p0010321", "west": -180.0}, {"awards": "1744958 Wei, Yong; 1744759 Dunham, Eric; 1744856 Bromirski, Peter", "bounds_geometry": null, "dataset_titles": "Data for: Ocean Surface Gravity Wave Excitation of Flexural Gravity and Extensional Lamb Waves in Ice Shelves; Simulation of flexural-gravity wave response of Antarctic ice shelves to tsunami and infragravity waves", "datasets": [{"dataset_uid": "200323", "doi": "10.25740/qy001dt7463", "keywords": null, "people": null, "repository": "Stanford Digital Repository", "science_program": null, "title": "Data for: Ocean Surface Gravity Wave Excitation of Flexural Gravity and Extensional Lamb Waves in Ice Shelves", "url": "https://doi.org/10.25740/qy001dt7463"}, {"dataset_uid": "601561", "doi": "10.15784/601561", "keywords": "Amundsen Sea; Antarctica; Glaciology", "people": "Tazhimbetov, Nurbek; Dunham, Eric; Almquist, Martin", "repository": "USAP-DC", "science_program": null, "title": "Simulation of flexural-gravity wave response of Antarctic ice shelves to tsunami and infragravity waves", "url": "https://www.usap-dc.org/view/dataset/601561"}], "date_created": "Mon, 16 May 2022 00:00:00 GMT", "description": "Understanding and being able to more reliably forecast ice mass loss from Antarctica is a critical research priority for Antarctic Science. Massive ice shelves buttress marine terminating glaciers, slowing the rate that land ice reaches the sea and, in turn, restraining the rate of sea level rise. To date, most work has focused on the destabilizing impacts of warmer air and water temperatures, resulting in melting that thins and weakens ice shelves. However, recent findings indicate that sea ice does not protect ice shelves from wave impacts as much as previously thought, which has raised the possibility that tsunamis and other ocean waves could affect shelf stability. This project will assess the potential for increased shelf fracturing from the impact of tsunamis and from heightened wave activity due to climate-driven changes in storm patterns and reduced sea-ice extent by developing models to investigate how wave impacts damage ice shelves. The modeling effort will allow for regional comparisons between large and small ice shelves, and provide an evaluation of the impacts of changing climate and storm patterns on ice shelves, ice sheets, glaciers, and, ultimately, sea level rise. This project will train graduate students in mathematical modeling and interdisciplinary approaches to Earth and ocean sciences.\u003cbr/\u003e\u003cbr/\u003eThis project takes a four-pronged approach to estimating the impact of vibrations on ice shelves at the grounding zone due to tsunamis, very long period, infragravity, and storm-driven waves. First, the team will use high-resolution tsunami modeling to investigate the response of ice shelves along the West Antarctic coast to waves originating in different regions of the Pacific Ocean. Second, it will compare the response to wave impacts on grounding zones of narrow and wide ice shelves. Third, it will assess the exposure risk due to storm forcing through a reanalysis of weather and wave model data; and, finally, the team will model the propagation of ocean-wave-induced vibrations in the ice from the shelf front to and across the grounding zone. In combination, this project aims to identify locations along the Antarctic coast that are subject to enhanced, bathymetrically-focused, long-period ocean-wave impacts. Linkages between wave impacts and climate arise from potential changes in sea-ice extent in front of shelves, and changes in the magnitude, frequency, and tracks of storms. Understanding the effects of ocean waves and climate on ice-shelf integrity is critical to anticipate their contribution to the amplitude and timing of sea-level rise. Wave-driven reductions in ice-shelf stability may enhance shelf fragmentation and iceberg calving, reducing ice shelf buttressing and eventually accelerating sea-level rise.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "COMPUTERS; AMD; Amd/Us; SEA ICE; Amundsen Sea; USAP-DC; USA/NSF; MODELS", "locations": "Amundsen Sea", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Integrated System Science", "paleo_time": null, "persons": "Dunham, Eric; Bromirski, Peter", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e MODELS \u003e MODELS", "repo": "Stanford Digital Repository", "repositories": "Stanford Digital Repository; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Do Ocean Wave Impacts Pose a Hazard to the Stability of West Antarctic Ice Shelves?", "uid": "p0010320", "west": null}, {"awards": "1341429 Ball, Becky", "bounds_geometry": "POLYGON((-68.205783 -60.706633,-65.9444531 -60.706633,-63.6831232 -60.706633,-61.4217933 -60.706633,-59.1604634 -60.706633,-56.8991335 -60.706633,-54.6378036 -60.706633,-52.3764737 -60.706633,-50.1151438 -60.706633,-47.8538139 -60.706633,-45.592484 -60.706633,-45.592484 -62.1204014,-45.592484 -63.5341698,-45.592484 -64.9479382,-45.592484 -66.3617066,-45.592484 -67.775475,-45.592484 -69.1892434,-45.592484 -70.6030118,-45.592484 -72.0167802,-45.592484 -73.4305486,-45.592484 -74.844317,-47.8538139 -74.844317,-50.1151438 -74.844317,-52.3764737 -74.844317,-54.6378036 -74.844317,-56.8991335 -74.844317,-59.1604634 -74.844317,-61.4217933 -74.844317,-63.6831232 -74.844317,-65.9444531 -74.844317,-68.205783 -74.844317,-68.205783 -73.4305486,-68.205783 -72.0167802,-68.205783 -70.6030118,-68.205783 -69.1892434,-68.205783 -67.775475,-68.205783 -66.3617066,-68.205783 -64.9479382,-68.205783 -63.5341698,-68.205783 -62.1204014,-68.205783 -60.706633))", "dataset_titles": "Climatic and environmental constraints on aboveground-belowground linkages and diversity across a latitudinal gradient in Antarctica", "datasets": [{"dataset_uid": "200289", "doi": "", "keywords": null, "people": null, "repository": "OSF - Center for Open Science", "science_program": null, "title": "Climatic and environmental constraints on aboveground-belowground linkages and diversity across a latitudinal gradient in Antarctica", "url": "https://osf.io/8xfrc/"}], "date_created": "Thu, 14 Apr 2022 00:00:00 GMT", "description": "The Antarctic Peninsula is experiencing rapid environmental changes, which will influence the community of organisms that live there. However, we know very little about the microscopic organisms living in the soil in this region. Soil biology (including bacteria, fungi, and invertebrates) are responsible for many important processes that sustain ecosystems, such as nutrient recycling. Without understanding the environmental conditions that influence soil biodiversity along the Antarctic Peninsula, our ability to predict the consequences of global change is strongly limited. This project will identify the soil community at many sites along the Antarctic Peninsula to discover how the community changes with environmental conditions from north to south. The project will also identify how the soil community at each site differs under different types of plants. Understanding more about the ways in which plant cover and climate conditions influence soil biodiversity will allow predictions of how communities will respond to future changes such as climate warming and invasive plant species. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. The investigators will engage with outreach to K-12 students and the general public both directly and through a blog and will participate in workshops for K-12 teachers. Additionally, the project will provide the opportunity for many undergraduate and graduate students of diverse backgrounds to be trained in interdisciplinary research.\u003cbr/\u003e\u003cbr/\u003eThe investigators will determine the nature and strength of plant-soil linkages in influencing soil community composition and diversity over a latitudinal gradient of environmental and climatic conditions. The goals are to (1) increase our understanding of current biogeography and diversity by providing in-depth knowledge of soil community composition and complexity as it relates to environmental and climatic characteristics; and (2) determine the nature of aboveground-belowground community linkages over varying spatial scales. The team will identify the composition and diversity of soil communities under key habitat types (grass, moss, algae, etc.). Microbial communities (bacteria, fungi, archaea) will be investigated using pyrosequencing for community composition analysis and metagenomic sequencing to identify functional capabilities. Invertebrates (nematodes, tardigrades, rotifers, microarthropods) will be extracted and identified to the lowest possible taxonomic level. Soil chemistry (pH, nutrient content, soil moisture, etc.) and climate conditions will be measured to determine the relationship between soil communities and physical and chemical properties. Structural equation modeling will be used to identify aboveground-belowground linkage pathways and quantify link strengths under varying environmental conditions.", "east": -45.592484, "geometry": "POINT(-56.8991335 -67.775475)", "instruments": null, "is_usap_dc": true, "keywords": "FUNGI; FIELD INVESTIGATION; AMD; Amd/Us; TERRESTRIAL ECOSYSTEMS; USA/NSF; ANIMALS/INVERTEBRATES; SOIL CHEMISTRY; BACTERIA/ARCHAEA; Antarctic Peninsula; ECOSYSTEM FUNCTIONS; USAP-DC", "locations": "Antarctic Peninsula", "north": -60.706633, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ball, Becky; Van Horn, David", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "OSF - Center for Open Science", "repositories": "OSF - Center for Open Science", "science_programs": null, "south": -74.844317, "title": "Collaborative Research: Climatic and Environmental Constraints on Aboveground-Belowground Linkages and Diversity across a Latitudinal Gradient in Antarctica", "uid": "p0010314", "west": -68.205783}, {"awards": "2053726 Hofmann, Gretchen", "bounds_geometry": "POLYGON((163 -77,163.4 -77,163.8 -77,164.2 -77,164.6 -77,165 -77,165.4 -77,165.8 -77,166.2 -77,166.6 -77,167 -77,167 -77.1,167 -77.2,167 -77.3,167 -77.4,167 -77.5,167 -77.6,167 -77.7,167 -77.8,167 -77.9,167 -78,166.6 -78,166.2 -78,165.8 -78,165.4 -78,165 -78,164.6 -78,164.2 -78,163.8 -78,163.4 -78,163 -78,163 -77.9,163 -77.8,163 -77.7,163 -77.6,163 -77.5,163 -77.4,163 -77.3,163 -77.2,163 -77.1,163 -77))", "dataset_titles": "Analyses combining ATAC-seq, RRBS, and RNA-seq data for purple urchins", "datasets": [{"dataset_uid": "200288", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Analyses combining ATAC-seq, RRBS, and RNA-seq data for purple urchins", "url": "https://github.com/snbogan/Sp_RRBS_ATAC"}], "date_created": "Thu, 14 Apr 2022 00:00:00 GMT", "description": "Part 1: Non-technical description:\r\n\tWith support from the Office of Polar Programs, this project will evaluate how an important part of the food web in the coastal ocean of Antarctica will respond to climate change. The focal study organism in the plankton is a shelled mollusk, the Antarctic pteropod, Limacina helicina antarctica, a Southern Ocean organism that this known to respond to climate driven changes in ocean acidification and ocean warming. Ocean acidification, the lowering of ocean pH via the absorption of atmospheric carbon dioxide in the surface of the ocean, is a change in the ocean that is expected to cross deleterious thresholds of pH within decades. This study will improve understanding of how pteropods will respond, which will provide insight into predicting the resilience of the Antarctic marine ecosystem during future changes, one of the planets last marine wildernesses. The project will use tools of molecular biology to examine specifically how gene expression is modulated in the pteropods, and further, how the changes and regulation of genes act to resist the stress of low pH and high temperature. In addition, this project supports the training of Ph.D. graduate students and advances the goal of inclusive excellence in STEM and in marine sciences, in particular. The students involved in this project are from groups traditionally under-represented in marine science including first-generation college students. Overall, the project contributes to the development of the U.S. work force and contributes to diversity and inclusive excellence in the geosciences.\r\n\r\nPart 2: Technical description: \r\nThe overarching goal of this project is to investigate the molecular response of the Antarctic thecosome pteropod, Limacina helicina antarctica to ocean acidification (OA) and ocean warming. The project will investigate changes in the epigenome of juvenile L. h. antarctica, by assessing the dynamics of DNA methylation in response to three scenarios of environmental conditions that were simulated in laboratory mesocosm CO2 experiments: (1) present-day pCO2 conditions for summer and winter, (2) future ocean acidification expected within 10-15 years, and (3) a multiple stressor experiment to investigate synergistic interaction of OA and high temperature stress. Recent lab-based mesocosm experiment research showed significant changes in the dynamics of global DNA methylation in the pteropod genome, along with variation in gene expression in response to abiotic changes. Thus, it is clear that juvenile L. h. antarctica are capable of mounting a substantial epigenetic response to ocean acidification. However, it is not known how DNA methylation, as an epigenetic process, is modulating changes in the transcriptome. In order to address this gap in the epigenetic knowledge regarding pteropods, the project will use next-generation sequencing approaches (e.g., RNA sequencing and reduced representation bisulfite sequencing) to integrate changes in methylation status with changes in gene expression in juvenile pteropods. Overall, this investigation is an important step in exploring environmental transcriptomics and phenotypic plasticity of an ecologically important member of Southern Ocean macrozoooplankton in response to anthropogenic climate change.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 167.0, "geometry": "POINT(165 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; McMurdo Sound; Amd/Us; FIELD INVESTIGATION; USA/NSF; AMD; MARINE ECOSYSTEMS; ANIMALS/INVERTEBRATES", "locations": "McMurdo Sound", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hofmann, Gretchen", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "GitHub", "repositories": "GitHub", "science_programs": null, "south": -78.0, "title": "The Role of the Epigenetic Mechanism, DNA Methylation, in the Tolerance and Resistance of Antarctic Pteropods to Ocean Acidification and Warming", "uid": "p0010313", "west": 163.0}, {"awards": "1932876 Ball, Becky", "bounds_geometry": "POLYGON((-59.666116 -62.15,-59.5128377 -62.15,-59.3595594 -62.15,-59.2062811 -62.15,-59.0530028 -62.15,-58.8997245 -62.15,-58.7464462 -62.15,-58.5931679 -62.15,-58.4398896 -62.15,-58.2866113 -62.15,-58.133333 -62.15,-58.133333 -62.1731502,-58.133333 -62.1963004,-58.133333 -62.2194506,-58.133333 -62.2426008,-58.133333 -62.265751,-58.133333 -62.2889012,-58.133333 -62.3120514,-58.133333 -62.3352016,-58.133333 -62.3583518,-58.133333 -62.381502,-58.2866113 -62.381502,-58.4398896 -62.381502,-58.5931679 -62.381502,-58.7464462 -62.381502,-58.8997245 -62.381502,-59.0530028 -62.381502,-59.2062811 -62.381502,-59.3595594 -62.381502,-59.5128377 -62.381502,-59.666116 -62.381502,-59.666116 -62.3583518,-59.666116 -62.3352016,-59.666116 -62.3120514,-59.666116 -62.2889012,-59.666116 -62.265751,-59.666116 -62.2426008,-59.666116 -62.2194506,-59.666116 -62.1963004,-59.666116 -62.1731502,-59.666116 -62.15))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 14 Apr 2022 00:00:00 GMT", "description": "Part I: Non-technical summary\u003cbr/\u003eThe Antarctic Peninsula warmed very rapidly in the late part of the 20th century, much faster than the global average, and this warming is predicted to resume and continue over the rest of the 21st century. One consequence of this rapid warming is the melting and subsequent retreat of glaciers, leading to an increase in newly-exposed land on the Peninsula that was previously covered with ice. Once new terrain is exposed, the process of ecological succession begins, with the arrival of early-colonizing plants, such as moss and lichens, and soil organisms - a process commonly referred to as the \u201cgreening\u201d of Antarctica. Early stages of succession will be an increasingly common feature on the Antarctic Peninsula, but the mechanisms by which they occur on the Antarctic continent is not well understood. Once the plants have established on the newly-exposed soil, they can change many important properties, such as water dynamics, nutrient recycling, soil development, and habitat for microscopic organisms, which will ultimately determine the structure and functioning of the future ecosystem as it develops. These relationships between vegetation, soil, and the associated microorganisms, referred to as \u201cplant-soil\u201d interactions, are something we know virtually nothing about. This project will be the first to make a comprehensive study of how the type of colonizing plant, and the expansion of those plants from climate change, will influence terrestrial ecosystems in Antarctica. Understanding these processes is critical to understanding how the greening Antarctica is occurring and how soil communities and processes are influenced by these expanding plant communities. Through this work the research team, will also be intensively training undergraduate and graduate students, including training of students from underrepresented groups and collaborative training of students from Chile and the US. Additionally, the research groups will continue their focus on scientific outreach with K-12 schools and the general public to expand awareness of the effects of climate change in Antarctica.\u003cbr/\u003e\u003cbr/\u003ePart II: Technical summary\u003cbr/\u003eIn this study, the researchers will use surveys across succession sites along the Antarctic Peninsula and Scotia Arc as well as a manipulative field experiment at glacier succession sites to test how species-specific plant functional traits impact soil properties and associated microbial and invertebrate communities in a greening Antarctica. In doing so, they will pursue three integrated aims to understand how Antarctic plant functional traits alter their soil environment and soil communities during succession after glacial retreat. AIM 1) Characterize six fundamental plant functional traits (thermal conductivity, water holding capacity, albedo, decomposability, tissue nutrient content, and secondary chemistry) among diverse Antarctica flora; AIM 2) Measure the relative effects of fundamental plant functional traits on soil physical properties and soil biogeochemistry across glacial succession gradients in Antarctica; and AIM 3) Measure the relative effects of fundamental plant functional traits on soil microbial and invertebrate communities across glacial succession gradients in Antarctica. They will explore how early-colonizing plants, especially mosses and lichens, alter soil physical, biogeochemical, and biological components, potentially impacting later patterns of succession. The researhcers will use intensive surveys of plant-soil interactions across succession sites and a manipulative transplant experiment in the South Shetland Islands, Antarctica to address their aims. The investigators will collect data on plant functional traits and their effects on soil physical properties, biogeochemistry, biotic abundance, and microbial metagenomics. The data collected will be the first comprehensive measures of the relative importance of plant functional types during glacial retreat and vegetative expansion from climate change in Antarctica, aiding our understanding of how plant functional group diversity and abundance are changing in a greening Antarctica.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -58.133333, "geometry": "POINT(-58.8997245 -62.265751)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; FIELD SURVEYS; ECOLOGICAL DYNAMICS; USA/NSF; SOIL CHEMISTRY; 25 De Mayo/King George Island; Antarctic Peninsula; PLANTS; Amd/Us; FUNGI; ANIMALS/INVERTEBRATES; USAP-DC; TERRESTRIAL ECOSYSTEMS; BACTERIA/ARCHAEA", "locations": "25 De Mayo/King George Island; Antarctic Peninsula", "north": -62.15, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ball, Becky", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -62.381502, "title": "Collaborative Research: Exploring the Functional Role of Antarctic Plants during Terrestrial Succession", "uid": "p0010315", "west": -59.666116}, {"awards": "2148517 Hancock, Cathrine", "bounds_geometry": "POLYGON((-60 -55,-51 -55,-42 -55,-33 -55,-24 -55,-15 -55,-6 -55,3 -55,12 -55,21 -55,30 -55,30 -57,30 -59,30 -61,30 -63,30 -65,30 -67,30 -69,30 -71,30 -73,30 -75,21 -75,12 -75,3 -75,-6 -75,-15 -75,-24 -75,-33 -75,-42 -75,-51 -75,-60 -75,-60 -73,-60 -71,-60 -69,-60 -67,-60 -65,-60 -63,-60 -61,-60 -59,-60 -57,-60 -55))", "dataset_titles": "Under ice trajectories for RAFOS enabled profiling floats in the Weddell Gyre", "datasets": [{"dataset_uid": "601652", "doi": "10.15784/601652", "keywords": "Antarctica; ANTXXIV/3; Argo Float; Artoa4argo; GPS Data; RAFOS; US Argo Program; Weddell Sea", "people": "Hancock, Cathrine", "repository": "USAP-DC", "science_program": null, "title": "Under ice trajectories for RAFOS enabled profiling floats in the Weddell Gyre", "url": "https://www.usap-dc.org/view/dataset/601652"}], "date_created": "Fri, 25 Mar 2022 00:00:00 GMT", "description": "The Weddell Gyre is one of the major components of the Southern Ocean circulation system, linking heat and carbon fluxes in the Antarctic Circumpolar Current to the continental margins. Water masses entering the Weddell Gyre are modified as they move in a great circular route around the gyre margin and change through processes involving air-sea-cryosphere interactions as well as through ocean eddies that mix properties across the gyre boundaries. Some of the denser water masses exit the gyre through pathways along the northern boundary, and ultimately ventilate the global deep ocean as Antarctic Bottom Water. While in-situ and satellite observations, as well as computer modeling efforts, provide estimates of the large-scale average flow within the gyre, details of the smaller-scale, or \"mesoscale\" eddy flow remain elusive. The proposed research will quantify mixing due to mesoscale eddies within the Weddell Gyre, as well as the transport of incoming deep water from the northeast, thought to be a result of transient eddies. Since the Weddell Gyre produces source water for about 40% of Antarctic Bottom Water formation, understanding the dynamics in this region helps to identify causes of documented changes in global bottom waters. This in turn, will give insight into how climate change is affecting global oceans, through modification of dense polar waters and Antarctic Bottom Water characteristics.\r\n\r\nThis project aims to track 153 RAFOS-enabled Argo floats in the ice-covered regions of the Weddell Gyre. The resultant tracks along with all available Argo and earlier float data will be used to calculate Eulerian and Lagrangian means and eddy statistics for the Weddell Gyre. The study will link RAFOS tracks with Argo profiles under ice, allowing one to characterize the importance of eddies in water column modification at critical ice-edge boundaries and leads. With RAFOS tracks near the northeastern limit of the gyre, the project will investigate the eddy-driven processes of incoming Circumpolar Deep Water, to understand better the mechanisms and volume fluxes involved. Previous work shows that a large fraction of the mean circulation in the southern and western limits of the gyre, where it contacts the Antarctic continent, occurs in a narrow boundary layer above the slope. The research here will integrate this flow structure into a complete interior and boundary layer mean circulation synthesis. The findings and products from the proposed work will improve the positioning of Argo profiles in the polar regions, which would allow for more accurate climatological maps and derived quantities. Estimates of meso-scale mixing may serve as a foundation for the development of new parameterization schemes employed in climate models, as well as local and global ocean circulation models in polar regions.", "east": 30.0, "geometry": "POINT(-15 -65)", "instruments": null, "is_usap_dc": true, "keywords": "OCEAN CURRENTS; WATER MASSES; BUOYS; USA/NSF; Weddell Sea; AMD; USAP-DC; Amd/Us", "locations": "Weddell Sea", "north": -55.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Hancock, Cathrine; Speer, Kevin", "platforms": "WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED \u003e BUOYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -75.0, "title": "Weddell Gyre Mean Circulation and Eddy Statistics from Floats", "uid": "p0010310", "west": -60.0}, {"awards": "0944150 Hall, Brenda", "bounds_geometry": "POLYGON((163.6 -77.5,163.7 -77.5,163.8 -77.5,163.9 -77.5,164 -77.5,164.1 -77.5,164.2 -77.5,164.3 -77.5,164.4 -77.5,164.5 -77.5,164.6 -77.5,164.6 -77.57,164.6 -77.64,164.6 -77.71,164.6 -77.78,164.6 -77.85,164.6 -77.92,164.6 -77.99,164.6 -78.06,164.6 -78.13,164.6 -78.2,164.5 -78.2,164.4 -78.2,164.3 -78.2,164.2 -78.2,164.1 -78.2,164 -78.2,163.9 -78.2,163.8 -78.2,163.7 -78.2,163.6 -78.2,163.6 -78.13,163.6 -78.06,163.6 -77.99,163.6 -77.92,163.6 -77.85,163.6 -77.78,163.6 -77.71,163.6 -77.64,163.6 -77.57,163.6 -77.5))", "dataset_titles": "Marshall Valley Radiocarbon Data; Marshall Valley U-Series Data; Royal Society Range Headland Moraine Belt Radiocarbon Data; Salmon Valley Radiocarbon Data", "datasets": [{"dataset_uid": "601528", "doi": "10.15784/601528", "keywords": "234U/230Th Dating; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Last Glacial Maximum; Marshall Drift; Marshall Valley; MIS 6; Royal Society Range", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Marshall Valley U-Series Data", "url": "https://www.usap-dc.org/view/dataset/601528"}, {"dataset_uid": "601555", "doi": "10.15784/601555", "keywords": "Antarctica; Last Glacial Maximum; McMurdo Sound; Radiocarbon Dates; Ross Sea Drift; Royal Society Range", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Royal Society Range Headland Moraine Belt Radiocarbon Data", "url": "https://www.usap-dc.org/view/dataset/601555"}, {"dataset_uid": "601556", "doi": "10.15784/601556", "keywords": "Antarctica; Last Glacial Maximum; McMurdo Sound; Radiocarbon Dates; Ross Sea Drift; Royal Society Range", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Salmon Valley Radiocarbon Data", "url": "https://www.usap-dc.org/view/dataset/601556"}, {"dataset_uid": "601529", "doi": "10.15784/601529", "keywords": "Algae; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marshall Valley; Radiocarbon; Ross Sea Drift; Royal Society Range", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Marshall Valley Radiocarbon Data", "url": "https://www.usap-dc.org/view/dataset/601529"}], "date_created": "Thu, 03 Mar 2022 00:00:00 GMT", "description": "This award supports a project to investigate the sensitivity of the Antarctic ice sheet (AIS) to global climate change over the last two Glacial/Interglacial cycles. The intellectual merit of the project is that despite its importance to Earth\u0027s climate system, we currently lack a full understanding of AIS sensitivity to global climate change. This project will reconstruct and precisely date the history of marine-based ice in the Ross Sea sector over the last two glacial/interglacial cycles, which will enable a better understanding of the potential driving mechanisms (i.e., sea-level rise, ice dynamics, ocean temperature variations) for ice fluctuations. This will also help to place present ice?]sheet behavior in a long-term context. During the last glacial maximum (LGM), the AIS is known to have filled the Ross Embayment and although much has been done both in the marine and terrestrial settings to constrain its extent, the chronology of the ice sheet, particularly the timing and duration of the maximum and the pattern of initial recession, remains uncertain. In addition, virtually nothing is known of the penultimate glaciation, other than it is presumed to have been generally similar to the LGM. These shortcomings greatly limit our ability to understand AIS evolution and the driving mechanisms behind ice sheet fluctuations. This project will develop a detailed record of ice extent and chronology in the western Ross Embayment for not only the LGM, but also for the penultimate glaciation (Stage 6), from well-dated glacial geologic data in the Royal Society Range. Chronology will come primarily from high-precision Accelerator Mass Spectrometry (AMS) Carbon-14 (14C) and multi-collector Inductively Coupled Plasma (ICP)-Mass Spectrometry (MS) 234Uranium/230Thorium dating of lake algae and carbonates known to be widespread in the proposed field area. ", "east": 164.6, "geometry": "POINT(164.1 -77.85)", "instruments": null, "is_usap_dc": true, "keywords": "LABORATORY; Amd/Us; AMD; USA/NSF; GLACIAL LANDFORMS; USAP-DC; Royal Society Range; GLACIER ELEVATION/ICE SHEET ELEVATION", "locations": "Royal Society Range", "north": -77.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hall, Brenda; Denton, George", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.2, "title": "Sensitivity of the Antarctic Ice Sheet to Climate Change over the Last Two Glacial/Interglacial Cycles", "uid": "p0010302", "west": 163.6}, {"awards": "1643248 Hall, Brenda", "bounds_geometry": "POLYGON((163.3 -77.8,163.43 -77.8,163.56 -77.8,163.69 -77.8,163.82 -77.8,163.95 -77.8,164.08 -77.8,164.21 -77.8,164.34 -77.8,164.47 -77.8,164.6 -77.8,164.6 -77.85,164.6 -77.9,164.6 -77.95,164.6 -78,164.6 -78.05,164.6 -78.1,164.6 -78.15,164.6 -78.2,164.6 -78.25,164.6 -78.3,164.47 -78.3,164.34 -78.3,164.21 -78.3,164.08 -78.3,163.95 -78.3,163.82 -78.3,163.69 -78.3,163.56 -78.3,163.43 -78.3,163.3 -78.3,163.3 -78.25,163.3 -78.2,163.3 -78.15,163.3 -78.1,163.3 -78.05,163.3 -78,163.3 -77.95,163.3 -77.9,163.3 -77.85,163.3 -77.8))", "dataset_titles": "Marshall Valley Radiocarbon Data; Marshall Valley U-Series Data; Pyramid Trough Radiocarbon Data; Walcott Glacier area radiocarbon data; Walcott Glacier Exposure Data", "datasets": [{"dataset_uid": "601616", "doi": "10.15784/601616", "keywords": "Antarctica; Beryllium-10; Exposure Age; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; McMurdo Sound; Royal Society Range; Walcott Glacier", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Walcott Glacier Exposure Data", "url": "https://www.usap-dc.org/view/dataset/601616"}, {"dataset_uid": "601528", "doi": "10.15784/601528", "keywords": "234U/230Th Dating; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Last Glacial Maximum; Marshall Drift; Marshall Valley; MIS 6; Royal Society Range", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Marshall Valley U-Series Data", "url": "https://www.usap-dc.org/view/dataset/601528"}, {"dataset_uid": "601614", "doi": "10.15784/601614", "keywords": "Algae; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Pyramid Trough; Radiocarbon; Radiocarbon Dates; Ross Sea Drift; Royal Society Range", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Pyramid Trough Radiocarbon Data", "url": "https://www.usap-dc.org/view/dataset/601614"}, {"dataset_uid": "601529", "doi": "10.15784/601529", "keywords": "Algae; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marshall Valley; Radiocarbon; Ross Sea Drift; Royal Society Range", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Marshall Valley Radiocarbon Data", "url": "https://www.usap-dc.org/view/dataset/601529"}, {"dataset_uid": "601615", "doi": "10.15784/601615", "keywords": "Algae; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Howchin Glacier; Radiocarbon; Radiocarbon Dates; Ross Sea Drift; Royal Society Range; Walcott Glacier", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Walcott Glacier area radiocarbon data", "url": "https://www.usap-dc.org/view/dataset/601615"}], "date_created": "Thu, 03 Mar 2022 00:00:00 GMT", "description": "The Antarctic Ice Sheet is the greatest potential contributor to sea-level change. However, the future response of the ice sheet to warming climate is recognized as one of the greatest uncertainties in sea-level projections. An understanding of past ice fluctuations can afford insight into ice-sheet response to climate change and thus is critical for improving sea-level predictions. In this project, we will reconstruct the behavior of the Antarctic Ice Sheet in the western Ross Sea region during the great global warming that ended the last ice age. Fluctuations in ice volume during this time period will allow us to characterize the factors that cause the ice sheet to advance and retreat and will enable us to distinguish between models that suggest repeated episodes of ice-sheet collapse vs those that indicate ice-sheet growth during warming climate. An understanding of the cause(s) of changes in ice volume during the warming that ended the last ice age has important implications for the future of the Antarctic Ice Sheet. ", "east": 164.6, "geometry": "POINT(163.95 -78.05)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIER ELEVATION/ICE SHEET ELEVATION; Royal Society Range; USA/NSF; USAP-DC; Amd/Us; AMD; LABORATORY; GLACIAL LANDFORMS", "locations": "Royal Society Range", "north": -77.8, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": null, "persons": "Hall, Brenda; Denton, George", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.3, "title": "Response of the Antarctic Ice Sheet to the last great global warming", "uid": "p0010301", "west": 163.3}, {"awards": "1643917 Fricker, Helen", "bounds_geometry": "POLYGON((-163.646 -84.186,-162.58715 -84.186,-161.5283 -84.186,-160.46945 -84.186,-159.4106 -84.186,-158.35175 -84.186,-157.2929 -84.186,-156.23405 -84.186,-155.1752 -84.186,-154.11635 -84.186,-153.0575 -84.186,-153.0575 -84.20871,-153.0575 -84.23142,-153.0575 -84.25413,-153.0575 -84.27684,-153.0575 -84.29955,-153.0575 -84.32226,-153.0575 -84.34497,-153.0575 -84.36768,-153.0575 -84.39039,-153.0575 -84.4131,-154.11635 -84.4131,-155.1752 -84.4131,-156.23405 -84.4131,-157.2929 -84.4131,-158.35175 -84.4131,-159.4106 -84.4131,-160.46945 -84.4131,-161.5283 -84.4131,-162.58715 -84.4131,-163.646 -84.4131,-163.646 -84.39039,-163.646 -84.36768,-163.646 -84.34497,-163.646 -84.32226,-163.646 -84.29955,-163.646 -84.27684,-163.646 -84.25413,-163.646 -84.23142,-163.646 -84.20871,-163.646 -84.186))", "dataset_titles": "Wideband magnetotelluric responses from Whillans Ice Stream, West Antarctica", "datasets": [{"dataset_uid": "601526", "doi": "10.15784/601526", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Stream; Magnetotelluric; Subglacial; Whillans Ice Stream", "people": "Siegfried, Matthew; Key, Kerry; Gustafson, Chloe; Fricker, Helen", "repository": "USAP-DC", "science_program": null, "title": "Wideband magnetotelluric responses from Whillans Ice Stream, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/601526"}], "date_created": "Sat, 26 Feb 2022 00:00:00 GMT", "description": "During November 2018 to January 2019 we carried out an extensive geophysical survey on the Whillans Ice Stream in West Antarctica. Our survey is the first to use magnetotelluric (MT) imaging to map subglacial groundwater water beneath an ice stream. We collected a total of 44 passive MT stations, as well as several active-source electromagnetic (EM) stations using a large loop transmitter system. These data will be used to study the distribution of groundwater at the base of the ice stream at both the grounding line where the ice stream turns into the Ross Ice Shelf and at Whillans Subglacial Lake. We also serviced a few long term GPS stations that have been recording data for several years and that have been used to track transient changes in ice velocity associated with basal water filling and draining in subglacial lakes. \r\n", "east": -153.0575, "geometry": "POINT(-158.35175 -84.29955)", "instruments": null, "is_usap_dc": true, "keywords": "Whillans Ice Stream; GROUND WATER; USA/NSF; USAP-DC; AMD; GEOMAGNETIC INDUCTION; Amd/Us; FIELD SURVEYS", "locations": "Whillans Ice Stream", "north": -84.186, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Key, Kerry; Fricker, Helen; Siegfried, Matt", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.4131, "title": "Mapping Antarctic Subglacial Water with Novel Electromagnetic Techniques", "uid": "p0010300", "west": -163.646}, {"awards": "0342484 Harwood, David", "bounds_geometry": "POINT(167.083333 -77.888889)", "dataset_titles": "Particle-size measurements at 3-m intervals for AND-2A sediment core, McMurdo Sound", "datasets": [{"dataset_uid": "601451", "doi": "10.15784/601451", "keywords": "Andrill; Antarctica; Continental Shelf; Diamict; McMurdo Sound; Miocene; Paleoclimate; Particle Size", "people": "Passchier, Sandra; Candice, Falk", "repository": "USAP-DC", "science_program": "ANDRILL", "title": "Particle-size measurements at 3-m intervals for AND-2A sediment core, McMurdo Sound", "url": "https://www.usap-dc.org/view/dataset/601451"}], "date_created": "Fri, 04 Feb 2022 00:00:00 GMT", "description": "ANDRILL is a scientific drilling program to investigate Antarctica\u0027s role in global climate change over the last sixty million years. The approach integrates geophysical surveys, new drilling technology, multidisciplinary core analysis, and ice sheet modeling to address four scientific themes: (1) the history of Antarctica\u0027s climate and ice sheets; (2) the evolution of polar biota and ecosystems; (3) the timing and nature of major tectonic and volcanic episodes; and (4) the role of Antarctica in the Earth\u0027s ocean-climate system. \u003cbr/\u003e\u003cbr/\u003eThis award initiates what may become a long-term program with drilling of two previously inaccessible sediment records beneath the McMurdo Ice Shelf and in South McMurdo Sound. These stratigraphic records cover critical time periods in the development of Antarctica\u0027s major ice sheets. The McMurdo Ice Shelf site focuses on the Ross Ice Shelf, whose size is a sensitive indicator of global climate change. It has recently undergone major calving events, and there is evidence of a thousand-kilometer contraction since the last glacial maximum. As a generator of cold bottom water, the shelf may also play a key role in ocean circulation. The core obtained from this site will also offer insight into sub-ice shelf sedimentary, biologic, and oceanographic processes; the history of Ross Island volcanism; and the flexural response of the lithosphere to volcanic loading, which is important for geophysical and tectonic studies of the region.\u003cbr/\u003e\u003cbr/\u003eThe South McMurdo Sound site is located adjacent to the Dry Valleys, and focuses on the major ice sheet overlying East Antarctica. A debate persists regarding the stability of this ice sheet. Evidence from the Dry Valleys supports contradictory conclusions; a stable ice sheet for at least the last fifteen million years or an active ice sheet that cycled through expansions and contractions as recently as a few millions of years ago. Constraining this history is critical to deep-time models of global climate change. The sediment cores will be used to construct an overall glacial and interglacial history for the region; including documentation of sea-ice coverage, sea level, terrestrial vegetation, and melt-water discharge events. The core will also provide a general chronostratigraphic framework for regional seismic studies and help unravel the area\u0027s complex tectonic history.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this project include formal and informal education, new research infrastructure, various forms of collaboration, and improving society\u0027s understanding of global climate change. Education is supported at the postdoctoral, graduate, undergraduate, and K-12 levels. Teachers and curriculum specialists are integrated into the research program, and a range of video resources will be produced, including a science documentary for television release. New research infrastructure includes equipment for core analysis and ice sheet modeling, as well as development of a unique drilling system to penetrate ice shelves. Drill development and the overall project are co-supported by international collaboration with scientists and the National Antarctic programs of New Zealand, Germany, and Italy. The program also forges new collaborations between research and primarily undergraduate institutions within the United States. \u003cbr/\u003e\u003cbr/\u003eAs key factors in sea-level rise and oceanic and atmospheric circulation, Antarctica\u0027s ice sheets are important to society\u0027s understanding of global climate change. ANDRILL offers new data on marine and terrestrial temperatures, and changes our understanding of extreme climate events like the formation of polar ice caps. Such data are critical to developing accurate models of the Earth\u0027s climatic future.", "east": 167.083333, "geometry": "POINT(167.083333 -77.888889)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; USAP-DC; FIELD SURVEYS; ICE SHEETS; USA/NSF; Amd/Us; PALEOCLIMATE RECONSTRUCTIONS; Ross Ice Shelf; SEDIMENTS", "locations": "Ross Ice Shelf", "north": -77.888889, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Harwood, David; Levy, Richard", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -77.888889, "title": "Collaborative Research: ANDRILL - - Investigating Antarcticas Role in Cenozoic Global Environmental Change", "uid": "p0010297", "west": 167.083333}, {"awards": "1744954 Lubin, Dan", "bounds_geometry": "POINT(-148.81 -81.65)", "dataset_titles": "Siple Dome Surface Energy Flux", "datasets": [{"dataset_uid": "601540", "doi": "10.15784/601540", "keywords": "Antarctica; Siple Dome; Spectroscopy", "people": "Ghiz, Madison; Lubin, Dan", "repository": "USAP-DC", "science_program": null, "title": "Siple Dome Surface Energy Flux", "url": "https://www.usap-dc.org/view/dataset/601540"}], "date_created": "Wed, 02 Feb 2022 00:00:00 GMT", "description": "We will measure the surface energy balance on West Antarctica as it relates to atmospheric forcing of surface melt and hydrofracturing of ice shelves and grounding-line ice cliffs. In this program we build upon recent experience with a major campaign jointly supported by the US Antarctic Program (USAP) and US Department of Energy (DOE), the Atmospheric Radiation Measurement (ARM) West Antarctic Radiation Experiment (AWARE). AWARE deployed a highly advanced suite of atmospheric and climate science instrumentation to McMurdo Station from December 2015 through December 2016, including spectral radiometers, research radars and lidars, and comprehensive meteorological equipment. AWARE also deployed a smaller suite of radiometers, lidars, and rawinsonde equipment to the West Antarctic Ice Sheet (WAIS) Divide Ice Camp during December 2015 and January 2016. This project\u2019s principal investigator, Dr. Lubin (Scripps Institution of Oceanography, SIO), was the AWARE lead scientist. For this program we will deploy a suite instruments to measure downwelling and net shortwave and longwave fluxes, sensible and latent heat fluxes, and near-surface meteorology. This suite of instruments will be self-reliant with power requirements and will be supportable in the field with flexible resources, for example a single Twin Otter aircraft mission. These measurements will be analyzed and interpreted to determine synoptic and mesoscale conditions that govern surface melt in West Antarctica, in the context of improving coupled climate model parameterizations.\r\n", "east": -148.81, "geometry": "POINT(-148.81 -81.65)", "instruments": null, "is_usap_dc": true, "keywords": "ICE SHEETS; Siple Dome; USAP-DC; ATMOSPHERIC RADIATION; AMD; FIELD SURVEYS; Amd/Us; USA/NSF", "locations": "Siple Dome", "north": -81.65, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Lubin, Dan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -81.65, "title": "Surface Energy Balance on West Antarctica and the Ross Ice Shelf", "uid": "p0010296", "west": -148.81}, {"awards": "1443557 Isbell, John", "bounds_geometry": "POLYGON((-180 -85,-177.1 -85,-174.2 -85,-171.3 -85,-168.4 -85,-165.5 -85,-162.6 -85,-159.7 -85,-156.8 -85,-153.9 -85,-151 -85,-151 -85.2,-151 -85.4,-151 -85.6,-151 -85.8,-151 -86,-151 -86.2,-151 -86.4,-151 -86.6,-151 -86.8,-151 -87,-153.9 -87,-156.8 -87,-159.7 -87,-162.6 -87,-165.5 -87,-168.4 -87,-171.3 -87,-174.2 -87,-177.1 -87,180 -87,179 -87,178 -87,177 -87,176 -87,175 -87,174 -87,173 -87,172 -87,171 -87,170 -87,170 -86.8,170 -86.6,170 -86.4,170 -86.2,170 -86,170 -85.8,170 -85.6,170 -85.4,170 -85.2,170 -85,171 -85,172 -85,173 -85,174 -85,175 -85,176 -85,177 -85,178 -85,179 -85,-180 -85))", "dataset_titles": "A LITHOFACIES ANALYSIS OF A SOUTH POLAR GLACIATION IN THE EARLY PERMIAN: PAGODA FORMATION, SHACKLETON GLACIER REGION, ANTARCTICA; A new stratigraphic framework built on U-Pb single-zircon TIMS agesand implications for the timing ofthe penultimate icehouse (Paran\u00e1 Basin, Brazil); Constraining late Paleozoic ice extent in the Paganzo Basin of western Argentina utilizing U-Pb detrital zircon geochronology for the lower Paganzo Group strata; Coupled stratigraphic and U-Pb zircon age constraints on the late Paleozoic icehouse-to-greenhouse turnover in south-central Gondwana; Isotopes to ice: Constraining provenance of glacial deposits and ice centers in west-central Gondwana; Late Permian soil-forming paleoenvironments on Gondwana: A review; Provenance of late Paleozoic glacial/post-glacial deposits in the eastern Chaco-Paran\u00e1 Basin, Uruguay and southernmost Paran\u00e1 Basin, Brazil; Supplemental material: Nitrogen-fixing symbiosis inferred from stable isotope analysis of fossil tree rings from the Oligocene of Ethiopia; When does large woody debris influence ancient rivers? Dendrochronology\r\napplications in the Permian and Triassic, Antarctica", "datasets": [{"dataset_uid": "200273", "doi": "10.1016/j.palaeo.2018.04.020", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Isotopes to ice: Constraining provenance of glacial deposits and ice centers in west-central Gondwana", "url": "https://www.sciencedirect.com/science/article/abs/pii/S0031018217309008?via%3Dihub"}, {"dataset_uid": "200274", "doi": "10.1130/G39213.1", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Supplemental material: Nitrogen-fixing symbiosis inferred from stable isotope analysis of fossil tree rings from the Oligocene of Ethiopia", "url": "https://pubs.geoscienceworld.org/gsa/geology/article-standard/45/8/687/207623/Nitrogen-fixing-symbiosis-inferred-from-stable"}, {"dataset_uid": "200272", "doi": "10.1016/j.jsames.2020.102899", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Constraining late Paleozoic ice extent in the Paganzo Basin of western Argentina utilizing U-Pb detrital zircon geochronology for the lower Paganzo Group strata", "url": "https://www.sciencedirect.com/science/article/pii/S0895981120304429?via%3Dihub#mmc1"}, {"dataset_uid": "200271", "doi": "10.1016/j.palaeo.2019.109544", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "When does large woody debris influence ancient rivers? Dendrochronology\r\napplications in the Permian and Triassic, Antarctica", "url": "https://www.sciencedirect.com/science/article/abs/pii/S0031018219304006?via%3Dihub"}, {"dataset_uid": "200270", "doi": "10.1016/j.jsames.2020.102989", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Provenance of late Paleozoic glacial/post-glacial deposits in the eastern Chaco-Paran\u00e1 Basin, Uruguay and southernmost Paran\u00e1 Basin, Brazil", "url": "https://www.sciencedirect.com/science/article/pii/S0895981120305320#mmc1"}, {"dataset_uid": "200269", "doi": "10.1130/G46740.1", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Coupled stratigraphic and U-Pb zircon age constraints on the late Paleozoic icehouse-to-greenhouse turnover in south-central Gondwana", "url": "https://gsapubs.figshare.com/articles/journal_contribution/Supplemental_material_Coupled_stratigraphic_and_U-Pb_zircon_age_constraints_on_the_late_Paleozoic_icehouse-to-greenhouse_turnover_in_south-central_Gondwana/12542069"}, {"dataset_uid": "200268", "doi": "10.1130/B31775.1.", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "A new stratigraphic framework built on U-Pb single-zircon TIMS agesand implications for the timing ofthe penultimate icehouse (Paran\u00e1 Basin, Brazil)", "url": "https://gsapubs.figshare.com/articles/journal_contribution/Supplemental_material_A_new_stratigraphic_framework_built_on_U-Pb_single-zircon_TIMS_ages_and_implications_for_the_timing_of_the_penultimate_icehouse_Paran_Basin_Brazil_/12535916"}, {"dataset_uid": "200267", "doi": "10.1016/j.palaeo.2021.110762", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Late Permian soil-forming paleoenvironments on Gondwana: A review", "url": "https://www.sciencedirect.com/science/article/abs/pii/S0031018221005472?via%3Dihub"}, {"dataset_uid": "200266", "doi": "10.2110/jsr.2021.004", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "A LITHOFACIES ANALYSIS OF A SOUTH POLAR GLACIATION IN THE EARLY PERMIAN: PAGODA FORMATION, SHACKLETON GLACIER REGION, ANTARCTICA", "url": "https://www.sepm.org/publications"}], "date_created": "Fri, 31 Dec 2021 00:00:00 GMT", "description": "The research focus of this collaborative proposal was to collect fossil plants, fossil wood, stratigraphic, sedimentologic, paleosol, and geochemical data from plants and the rocks that contain them in order to reconstruct the extent of the Gondwana glaciation in the Shackleton Glacier (SHK) area, the invasion and subsequent flourishing of life following glacial retreat, changes to the physical environment, and the eventual recovery of plant life after the Late Permian biotic events. Only in Antarctica does a complete polar-to-near-polar succession occur across this climatic and biologic transition. The SHK is an important one as it is one of the few regions in the world where the Permian-Triassic boundary (PTB) is exposed within terrestrial rocks. In addition, outcrops in the SHK area extend from the glacigenic deposits of the Upper Carboniferous-Lower Permian through to the Upper Triassic and thus record ecosystems and the plants that inhabited them from the Gondwana icehouse into the Late Permian-Early Triassic greenhouse and into presumed \"full recovery\" of floras from the PTB extinctions in the Late Triassic.\r\n\r\nThe project encompassed a multidisciplinary plan that used various types of paleobotanical expertise, integrated with detailed sedimentology, stratigraphy, and geochemistry, in order to reconstruct Permian-Triassic plant communities and their paleoenvironments. This interdisciplinary approach is a powerful tool to uncover details of Antarctica\u2019s complex late Paleozoic and Mesozoic environmental, climatic, and biotic history which included: 1) glaciation/deglaciation, 2) development and evolution of a post-glacial landscape and biota, 3) environmental and biotic change associated with the end-Permian mass extinction events, 4) earliest ecosystems in the Triassic, 5) greenhouse conditions in the Triassic, 6) full \u2019recovery\u2019 of floras and ecosystems by the Late Triassic, and, through all of these events, 7) development and changes in a foreland basin system. Three interrelated focus areas, each delimited by distinct hypotheses and action strategies, provided the framework to trace floral diversity and environmental evolution after the retreat of glaciers through to the Late Triassic. Antarctica is the only place on Earth that includes extensive outcrops of high-paleolatitude terrestrial rocks, combined with widespread and well-preserved plant fossils, and that spans this crucial time.\r\n\r\nThe research and broader impacts of this proposal were integrated into action strategies that have been successful in the past. Compression floras were collected (constrained by stratigraphy) both quantitatively and qualitatively in order to obtain biodiversity and abundance data, and as a data source for paleoecological analysis. Even in formations where megafossils were unknown (e.g., Lower Permian), fossil wood is present so that anatomy and geochemistry of tree rings were examined. Standard sedimentologic and stratigraphic analyses were performed, as well as paleosol analyses, including mineralogic and major- and trace-element geochemistry. Collections will also be made for U-Pb zircon geochronology to better constrain geologic and biotic events.\r\n\r\nThe Broader Impacts of the project involved education and outreach initiatives that included women and under-represented groups in the excitement of Antarctic earth sciences: 1) Continuing successful public outreach, teaching, and mentoring of women and under-represented students in Antarctic research; 2) Participation in workshops for under-represented groups via the Expanding Your Horizons Program in Kansas, the TRIO program (KU), and the STELAR summer workshop (UWM) for high-school students. 3) Outreach via the KU Natural History Museum; 4) Exploring Antarctic geosciences through continued presentations to pre K-12 school groups, and field and lab activities at UWM, as well as links from McMurdo Station and satellite conferences from the field with K-12 science classes in Wisconsin and Illinois.", "east": 170.0, "geometry": "POINT(-170.5 -86)", "instruments": null, "is_usap_dc": true, "keywords": "Shackleton Glacier; SEDIMENTARY ROCKS; GLACIATION", "locations": "Shackleton Glacier", "north": -85.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Isbell, John", "platforms": null, "repo": "Publication", "repositories": "Publication", "science_programs": null, "south": -87.0, "title": "Collaborative Research: Permian and Triassic Icehouse to Greenhouse Paleoenvironments and Paleobotany in the Shackleton Glacier Area, Antarctica", "uid": "p0010287", "west": -151.0}, {"awards": "2039419 Swanger, Kate", "bounds_geometry": "POLYGON((161 -77.3,161.2 -77.3,161.4 -77.3,161.6 -77.3,161.8 -77.3,162 -77.3,162.2 -77.3,162.4 -77.3,162.6 -77.3,162.8 -77.3,163 -77.3,163 -77.35,163 -77.4,163 -77.45,163 -77.5,163 -77.55,163 -77.6,163 -77.65,163 -77.7,163 -77.75,163 -77.8,162.8 -77.8,162.6 -77.8,162.4 -77.8,162.2 -77.8,162 -77.8,161.8 -77.8,161.6 -77.8,161.4 -77.8,161.2 -77.8,161 -77.8,161 -77.75,161 -77.7,161 -77.65,161 -77.6,161 -77.55,161 -77.5,161 -77.45,161 -77.4,161 -77.35,161 -77.3))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 16 Dec 2021 00:00:00 GMT", "description": "The McMurdo Dry Valleys are the largest ice-free region in Antarctica and home to a seasonally active hydrologic system, with streams and saline lakes. Streams are fed by summer meltwater from local glaciers and snowbanks. Therefore, streamflow is tied to summer climate conditions such as air temperatures, ground temperatures, winds, and incoming solar radiation. Based on 50 years of monitoring, summer stream activity has been observed to change, and it likely varied during the geologic past in response to regional climate change and fluctuating glaciers. Thus, deposits from these streams can address questions about past climate, meltwater, and lake level changes in this region. How did meltwater streamflow respond to past climate change? How did streamflow vary during periods of glacial advance and retreat? At what times did large lakes fill many of the valleys and what was their extent? The researchers plan to acquire a record of stream activity for the Dry Valleys that will span the three largest valleys and a time period of about 100,000 years. This record will come from a series of active and ancient alluvial fans that were deposited by streams as they flowed from valley sidewalls onto valley floors. The study will provide a long-term context with which to assess recent observed changes to stream activity and lake levels. The research will be led by two female mid-career investigators and contribute significantly to student research opportunities and education. The research will contribute to graduate and undergraduate education by including students in both field and laboratory research, as well as incorporating data and results into the classroom. The research will be disseminated to K-12 and non-scientific communities through outreach that includes professional development training for K-12 teachers in eastern Massachusetts, development of hands-on activities, visits to K-12 classrooms, and STEM education and literacy activities in North Carolina.\r\n\r\nThe PIs propose to constrain rates of fluvial deposition and periods of increased fluvial activity in the McMurdo Dry Valleys during the Holocene and late Pleistocene. During 50 years of hydrologic monitoring in the Dry Valleys, scientists have observed that streams exhibit significant response to summer conditions. Previous studies of glacial and lacustrine deposits indicate regional glacier advance in the Dry Valleys during recent interglacial periods and high lake levels during and after the Last Glacial Maximum (LGM), with potentially significant low and high stands during the Holocene. However, the geologic record of meltwater activity is poorly constrained. The PIs seek to develop the first spatially-extensive record of stream deposition in the Dry Valleys by analyzing and dating alluvial fans. Given that alluvial fans are deposited by summer meltwater streams in a relatively stable tectonic setting, this record will serve as a proxy of regional summer climate conditions. Meltwater streams are an important component of the regional hydrologic system, connecting glaciers to lakes and affecting ecosystems and soils. A record of fluvial deposition is key to understanding the relationship between past climate change and regional hydrology. The proposed research will include remote- and field-based mapping of alluvial fans, stream channels, and meltwater sources as well as modeling potential incoming solar radiation to the fans and moisture sources during the austral summer. In the field, the PIs will document stratigraphy, collect near-surface sediments from 25 fans across four valleys (Taylor, Pearse, Wright, and Victoria), and collect 2- to 3-m vertical cores of ice-cemented sediments from three alluvial fan complexes. The PIs will then conduct depositional dating of fluvial sands via optically stimulated luminescence, and analyze mineralogy and bulk major element chemistry with X-ray powder diffraction and X-ray fluorescence. From these analyses, the PIs propose to (1) determine the timing of local- to regional-scale periods of high fluvial deposition, (2) calculate depositional rates, and (3) constrain depositional environments and sediment provenance. Given that many of the alluvial fans occur below the hypothesized maximum extents of glacially-dammed lakes in Wright and Victoria valleys, detailed stratigraphy, sediment provenance, and OSL dating of these fans could shed light on ongoing debates regarding the timing and extent of LGM and post-LGM lakes. The work will support a postdoctoral researcher, a PhD student, and many undergraduate and master\u2019s students in cross-disciplinary research that spans stratigraphy, geochemistry, paleoclimatology and physics.", "east": 163.0, "geometry": "POINT(162 -77.55)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; Amd/Us; SEDIMENTS; USA/NSF; AMD; Dry Valleys; USAP-DC", "locations": "Dry Valleys", "north": -77.3, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Swanger, Kate", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -77.8, "title": "Collaborative Research: Holocene and Late Pleistocene Stream Deposition in the McMurdo Dry Valleys, Antarctica as a Proxy for Glacial Meltwater and Paleoclimate", "uid": "p0010285", "west": 161.0}, {"awards": "2037561 Jenouvrier, Stephanie", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Code for \u015een et al. 2023; Detecting climate signals in populations: case of emperor penguin", "datasets": [{"dataset_uid": "200373", "doi": "https://doi.org/10.5281/zenodo.7803266", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Code for \u015een et al. 2023", "url": "https://zenodo.org/record/7803266"}, {"dataset_uid": "601491", "doi": "10.15784/601491", "keywords": "Antarctica", "people": "Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Detecting climate signals in populations: case of emperor penguin", "url": "https://www.usap-dc.org/view/dataset/601491"}], "date_created": "Wed, 08 Dec 2021 00:00:00 GMT", "description": "Overview: We aim to provide the most detailed investigation to date of the factors that influence predictability of Antarctic climate, the coupling of climate to penguins populations, and the integration of the two to optimize ecological forecasts. This integrated understanding is critical for guiding future ecological and climate research, prioritizing bio-physical monitoring efforts, and informing conservation decision-making. Our study will reveal the influence of climate system dynamics on ecological predictability across a range of scales and will examine how this role differs among ecological processes, species and regions of Antarctica. \r\n\r\nIntellectual Merit: Many biophysical processes will change in the coming century. Yet, the mechanisms controlling the predictability of many climate processes are still poorly understood, limiting progress in climate forecasting. In parallel, ecological forecasting remains a nascent discipline. In particular, comparative assessments of predictability, both within and among species, are critically needed to understand the factors that allow (or prevent) useful ecological forecasts. While important for ecological science generally, this need is particularly pressing in Antarctica where the environment is highly dynamic, strongly coupled to biological processes, and likely to change in the future. Improved ecological forecasting therefore requires interdisciplinary efforts to understand the causes of predictability in climate, and in tandem, how climate influences the predictability of natural populations.\r\nThis proposed research will examine the predictability of Antarctic climate and its influence on penguin demographic response predictability at various temporal and spatial scales using the longest datasets available for two penguin species. Specifically, the PI will 1) identify the physical mechanisms giving rise to climate predictability in Antarctica, 2) identify the relationships between climate and ecological processes at a range of scales, and 3) reveal the factors controlling ecological predictability across a range of scales (e.g., those relevant for short-term adaptive management versus those relevant at end-of-century timescales). These objectives will be achieved using the analysis of existing climate data and Atmosphere-Ocean Global Circulation Models (AGOCMs), with coupled analysis of existing long-term demographic data for multiple seabird species that span a range of ecological niches, life histories, and study sites across the continent.\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "ECOLOGICAL DYNAMICS; PENGUINS; Amd/Us; Antarctica; USA/NSF; SEA ICE; NOT APPLICABLE; USAP-DC; AMD", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jenouvrier, Stephanie; Holland, Marika", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "Zenodo", "repositories": "USAP-DC; Zenodo", "science_programs": null, "south": -90.0, "title": "Integrating Antarctic Environmental and Biological Predictability to Obtain Optimal Forecasts", "uid": "p0010282", "west": -180.0}, {"awards": "1951500 Jenouvrier, Stephanie", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "The impact of boldness on demographic rates and lifehistory outcomes in the wandering albatross", "datasets": [{"dataset_uid": "601770", "doi": "10.15784/601770", "keywords": "Antarctica; Cryosphere; Demography; Sub-Antarctic", "people": "Joanie, Van de Walle; Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "The impact of boldness on demographic rates and lifehistory outcomes in the wandering albatross", "url": "https://www.usap-dc.org/view/dataset/601770"}], "date_created": "Wed, 08 Dec 2021 00:00:00 GMT", "description": "Overview: To date, studies that have addressed the impacts of global changes have mainly focused on linking climate variability and/or human disturbances to individual life history traits, population dynamics or distribution. However, individual behavior and plasticity mediate these responses. The goal of this project is to understand mechanisms linking environmental changes (climate \u0026 fisheries)- behavioral personality type \u2013 plasticity in foraging behaviors- life history traits \u2013 population dynamics for a seabird breeding in the southern ocean: the wandering albatross. This project will also forecast the population structure and growth rate using the most detailed mechanistic model to date for any wild species incorporating behaviors in an eco-evolutionary context. Specifically, the investigators will (1) characterize the life history strategies along the shy-bold continuum of personalities and across environmental conditions; (2) understand the link between phenotypic plasticity in foraging effort and personality; (3) characterize the heritability of personality and foraging behaviors; (4) develop a stochastic eco-evolutionary model to understand and forecast the distribution of bold and shy individuals within the population and the resulting effect on population growth rate in a changing environment by integrating processes from goals 1, 2 and 3. To date, this has been hampered by the lack of long-term data on personality and life histories in any long-lived species in the wild. For the first time ever, we have tested in a controlled environment the response to a novel situation for ~1800 individuals for more than a decade to define individual personality variation along the shy-bold continuum that we can relate to the life history traits over the entire species life cycle using unique long-term individual mark-recapture data sets for this iconic polar species. The novelty of this project thus lies in the combination of personality, foraging and demographic data to understand and forecast population responses to global change using state-of-the-art statistical analysis and eco-evolutionary modeling approaches. \r\nIntellectual Merit: While there is ubiquitous evidence of personality differences across taxa, the implications for life-history are less clear, and the consequences for population dynamics virtually unexplored empirically. How the phenotypic distributions of personality and foraging behaviors types within a population is created and maintained by ecological (demographic and phenotypic plasticity) and evolutionary (heritability) processes remain an open question. Personality traits are a crucial link between how individuals acquire resources, and how they allocate these to reproduction and survival, and this trade-off drives population dynamics. However, although some studies have found different foraging behaviors or breeding performances between personality types, none have established the link between personality- foraging behaviors \u2013 life histories (both reproduction and survival, and their covariations) in the context of climate change. Furthermore plasticity in foraging behaviors is not considered in the pace-of-life syndrome, which has potentially hampered our ability to find covariation between personality and life history trade-off. Research into the heritability of personality traits has revealed a strong heritable component, but studies looking at the heritability of foraging behaviors are lacking. For the first time ever, this project will fill these knowledge gaps and integrate in an eco-evolutionary model the complex interaction among individual personality and foraging plasticity, heritability of personality and foraging behaviors, life history strategies, population dynamics in a changing environment (fisheries and climate). Furthermore, this project will provide for the first time projections of population size and structure under future global change using state-of-the-art climate projections from IPCC-class atmospheric-oceanic global circulation models.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; NOT APPLICABLE; AMD; ECOLOGICAL DYNAMICS; OCEAN TEMPERATURE; USA/NSF; Antarctica; SPECIES/POPULATION INTERACTIONS; PENGUINS; Amd/Us", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Jenouvrier, Stephanie; Patrick, Samantha", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "NSFGEO-NERC: Integrating Individual Personality Differences in the Evolutionary Ecology of a Seabird in the Rapidly Changing Polar Environment", "uid": "p0010283", "west": -180.0}, {"awards": "2040571 Smith, Walker; 2040199 Ainley, David; 2040048 Ballard, Grant", "bounds_geometry": "POLYGON((164 -74,165.6 -74,167.2 -74,168.8 -74,170.4 -74,172 -74,173.6 -74,175.2 -74,176.8 -74,178.4 -74,180 -74,180 -74.4,180 -74.8,180 -75.2,180 -75.6,180 -76,180 -76.4,180 -76.8,180 -77.2,180 -77.6,180 -78,178.4 -78,176.8 -78,175.2 -78,173.6 -78,172 -78,170.4 -78,168.8 -78,167.2 -78,165.6 -78,164 -78,164 -77.6,164 -77.2,164 -76.8,164 -76.4,164 -76,164 -75.6,164 -75.2,164 -74.8,164 -74.4,164 -74))", "dataset_titles": "Seaglider data from the Western Ross Sea, Antarctica, November 2022-January 2023", "datasets": [{"dataset_uid": "200418", "doi": "10.5285/0a1c43b9-4738-75e0-e063-6c86abc0ea24", "keywords": null, "people": null, "repository": "BODC", "science_program": null, "title": "Seaglider data from the Western Ross Sea, Antarctica, November 2022-January 2023", "url": "\r\nhttps://www.bodc.ac.uk/data/published_data_library/catalogue/10.5285/0a1c43b9-4738-75e0-e063-6c86abc0ea24\r\n"}], "date_created": "Mon, 25 Oct 2021 00:00:00 GMT", "description": "Part I: Non-technical description: \r\nThe Ross Sea, a globally important ecological hotspot, hosts 25-45% of the world populations of Ad\u00e9lie and emperor penguins, South Polar skuas, Antarctic petrels, and Weddell seals. It is also one of the few marine protected areas designated within the Southern Ocean, designed to protect the workings of its ecosystem. To achieve that goal requires participation in an international research and monitoring program, and more importantly integration of what is known about these mesopredators, which is a lot, and the biological oceanography of their habitat, parts of which are also well known. The project will acquire data on these species\u2019 food web dynamics through assessing of Ad\u00e9lie penguin foraging behavior, an indicator species, while multi-sensor ocean gliders autonomously quantify prey abundance and distribution as well as ocean properties, including phytoplankton, at the base of the food web. Additionally, satellite imagery will quantify sea ice and whales (competitors) within the penguins\u2019 foraging area. Seasoned researchers and students will be involved, as will a public outreach program that reaches \u003e200 school groups per field season, and \u003e1M visits to the website of an ongoing, related project. Lessons about ecosystem change, and how it is measured, i.e. the STEM fields, will be emphasized. Results will be distributed to the world science and management communities. \r\n\r\nPart II: Technical description: \r\nThis project, in collaboration with the National Environmental Research Council (UK), assesses food web structure in the southwestern Ross Sea, a major portion of the recently designated Ross Sea Region Marine Protected Area, designed to protect the region\u2019s \u201cfood web structure, dynamics and function.\u201d Success requires in-depth, integated ecological information. The western Ross Sea, especially the marginal ice zone of the Ross Sea Polynya (RSP), supports global populations of iconic and indicator species: 25% of emperor penguins, 30% of Ad\u00e9lie penguins, 50% of South Polar skuas, and 45% of Weddell seals. However, while individually well researched, for these members of the upper food web information has been poorly integrated into understanding of Ross Sea food web dynamics and biogeochemistry. Information from multi-sensor ocean gliders, high-resolution satellite imagery, diet analysis and biologging of penguins, when integrated will facilitate understanding of the preyscape within the intensively investigated biogeochemistry of the RSP. UK participation covers a number of glider functions (e.g., providing a state-of-the-art glider at minimal cost, glider programming, ballasting, and operation) and supplies expertise to evaluate the oceanographic conditions of the study area. Several student will be involved, as well as an existing outreach program in a related penguin research project reaching annually \u003e200 school groups and \u003e1M website visits. \r\n", "east": 180.0, "geometry": "POINT(172 -76)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; AQUATIC SCIENCES; USA/NSF; Amd/Us; Biologging; AMD; Foraging Ecology; FIELD SURVEYS; Ross Sea; Adelie Penguin", "locations": "Ross Sea", "north": -74.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Ainley, David; Santora, Jarrod; Varsani, Arvind; Smith, Walker; Ballard, Grant; Schmidt, Annie", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "BODC", "repositories": "BODC", "science_programs": null, "south": -78.0, "title": "NSFGEO-NERC: Collaborative Research \"P2P: Predators to Plankton -Biophysical Controls in Antarctic Polynyas\"", "uid": "p0010273", "west": 164.0}, {"awards": "1745055 Stearns, Leigh; 1745043 Simkins, Lauren", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Circum-Antarctic grounding-line sinuosity; Elevation transects from Pine Island Bay; Pennell Trough, Ross Sea bathymetry and glacial landforms", "datasets": [{"dataset_uid": "601484", "doi": "10.15784/601484", "keywords": "Antarctica; Bed Roughness; Bed Slope; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Pinning Points", "people": "Riverman, Kiya; Simkins, Lauren; Stearns, Leigh", "repository": "USAP-DC", "science_program": null, "title": "Circum-Antarctic grounding-line sinuosity", "url": "https://www.usap-dc.org/view/dataset/601484"}, {"dataset_uid": "601474", "doi": "10.15784/601474", "keywords": "Antarctica; Bathymetry; Elevation; Geomorphology; Glacial History; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marine Geoscience; NBP1502; Pennell Trough; Ross Sea; R/v Nathaniel B. Palmer", "people": "Prothro, Lindsay; Anderson, John; Eareckson, Elizabeth; Munevar Garcia, Santiago; Greenwood, Sarah; Simkins, Lauren", "repository": "USAP-DC", "science_program": null, "title": "Pennell Trough, Ross Sea bathymetry and glacial landforms", "url": "https://www.usap-dc.org/view/dataset/601474"}, {"dataset_uid": "601774", "doi": "10.15784/601774", "keywords": "Antarctica; Bed Roughness; Cryosphere; Geomorphology; Pine Island Bay", "people": "Munevar Garcia, Santiago", "repository": "USAP-DC", "science_program": null, "title": "Elevation transects from Pine Island Bay", "url": "https://www.usap-dc.org/view/dataset/601774"}], "date_created": "Tue, 28 Sep 2021 00:00:00 GMT", "description": "The goals of this collaborative project are to merge empirical observations from the deglaciated Antarctic continental shelf and 1-D and 3-D numerical model experiments to test the sensitivity of marine-based ice sheets to subglacial topography with collaborators at the University of Kansas (L. Stearns, C. van der Veen). We focus on five glacial systems (i.e., flowlines) across the Amundsen Sea, Ross Sea, and George V Coast of Wilkes Land that extended to/near the continental shelf break at the Last Glacial Maximum \u2013 with a range of bed characteristics, topographic features, oceanographic and climatic conditions, and patterns of past ice flow and grounding line retreat. Specifically, at the University of Virginia, we (L. Simkins, S. Munevar Garcia) are: (ongoing) exploring bed roughness across the flowlines to determine the sensitivity of ice flow and grounding line behavior to different scales and wavelengths of bed topography/roughness; (upcoming) developing an empirical relationship between ice-marginal landform sediment volume and grounding line occupation time, and combining this with sedimentological analyses and new absolute age constraints to produce more comprehensive timelines of grounding line retreat, influential boundary conditions and processes, and determine the presence/absence of ice shelves; (ongoing) integrating quantitative and qualitative paleo- and offshore data to be incorporated into and/or validate 1-D and 3-D model experiments further testing the sensitivity of the five glacial systems to bed topography; and (completed) co-developing community engagement and education materials that focus on merging paleo-observations and model information of the Antarctic Ice Sheet from the LGM to the present \r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "MARINE SEDIMENTS; USAP-DC; Amd/Us; GLACIERS; BATHYMETRY; GLACIAL LANDFORMS; Antarctica; AMD; USA/NSF; R/V NBP", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Simkins, Lauren; Stearns, Leigh; Anderson, John; van der Veen, Cornelis", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Topographic controls on Antarctic Ice Sheet grounding line retreat - integrating models and observations", "uid": "p0010269", "west": -180.0}, {"awards": "1916665 Mahon, Andrew; 2225144 Halanych, Kenneth; 1916661 Halanych, Kenneth", "bounds_geometry": "POLYGON((-72 -61,-69.8 -61,-67.6 -61,-65.4 -61,-63.2 -61,-61 -61,-58.8 -61,-56.6 -61,-54.4 -61,-52.2 -61,-50 -61,-50 -61.8,-50 -62.6,-50 -63.4,-50 -64.2,-50 -65,-50 -65.8,-50 -66.6,-50 -67.4,-50 -68.2,-50 -69,-52.2 -69,-54.4 -69,-56.6 -69,-58.8 -69,-61 -69,-63.2 -69,-65.4 -69,-67.6 -69,-69.8 -69,-72 -69,-72 -68.2,-72 -67.4,-72 -66.6,-72 -65.8,-72 -65,-72 -64.2,-72 -63.4,-72 -62.6,-72 -61.8,-72 -61))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 22 Sep 2021 00:00:00 GMT", "description": "Overview: \r\nThe ice cover of Antarctica is changing rapidly, and some reports already suggest we are at, or possibly beyond, the tipping point for the Western Antarctic Ice Sheet collapse. Loss of this ice sheet will have profound effects on marine fauna, including dramatically changing habitat availability for benthic marine species in the Southern Ocean. Formation and collapse of the Western Antarctic Ice Sheet is a cyclical process suggesting that we can learn how fauna respond to ice loss by examining historical climate conditions. Evidence from sediment cores suggests a near complete collapse occurred ~1.1 MYA and modeling suggests a collapse as recent at 125 KYA. During such periods, transantarctic seaways connected the Ross and Weddell Seas. Interestingly, most theories regarding marine invertebrate distributions around the Antarctic focus on dispersal by the Antarctic Circumpolar Current or population bottlenecks and expansions generated by repeated cycles of glaciation and fail to account for transcontinental seaways. Although the impact of previous seaways on genetic structure of present-day populations has been largely ignored, a growing body of data reveal historical connections between Ross and Weddell invertebrate communities, suggesting historical dispersal between these present-day disconnected and distant basins. Future ice shelf collapses will likely reestablish such connections causing redistribution of marine taxa. By exploring alternative hypotheses about the factors that may have shaped patterns of biodiversity in the last couple of million years, our proposed work will aid prediction of possible changes that may, or may not, occur as the Antarctic ice sheets continue to deteriorate.\r\nIntellectual Merit: \r\nThe overarching goal of this research is to understand environmental factors that have shaped patterns of present-day diversity in Antarctic benthic marine invertebrates. Building on our previous work examining circumpolar distributions of multiple marine benthic invertebrate, we are particularly interested in assessing if transantarctic waterways may help explain observed similarities between the Ross and Weddell Seas better than other possible explanations (e.g., dispersal by the Antarctic Circumpolar Current, or expansion from common glacial refugia). To this end, we will employ population genomic approaches using Single Nucleotide Polymorphism (SNP) markers that sample thousands of loci across the genome. Building on our previous phylogeographic studies, we will target 7 Antarctic benthic invertebrate taxa to test alternative hypothesis accounting for population genetic structure. Additionally, the current paradigm is that divergence between closely related, often cryptic, species is the result of genetic drift due to population bottlenecks caused by glaciation. We will directly test this assumption by mapping SNP data on to draft genomes of three of our target taxa to assess the degree of genetic divergence and look for signs of selection. If linkage groups under selection are found, we will examine cellular mechanisms under selection. Thus, our research directly addresses NSF programmatic goals to understand how Antarctic biota evolve and adapt.\r\nBroader Impacts: \r\nOur approach will test several hypotheses that dominate the current understanding of marine biodiversity patterns in the Antarctic providing relevance to several fields of Antarctic science. Also, there are implications for understanding and predicting effects of future ice shelf collapse. The PIs are committed to developing the next generation of researchers and actively engage underrepresented groups at all career stages. We expect to train a minimum of 4 graduate students, a postdoc and several undergraduates on this project. This work will include several specific outreach activities including continuation of our past social media efforts with cruise blogs which were accessed by several thousand unique IP addresses and presentations in K-8 classrooms that reach about 300+ children a year. We also propose to develop 15-20 short YouTube videos on Antarctic genomics as outreach products, we will conduct a photo exhibition, and we will develop two 3-day workshops aimed at students to introduce them to bioinformatics approaches. These works will have formal assessment. \r\nThis proposal requires fieldwork in the Antarctic. \r\n", "east": -50.0, "geometry": "POINT(-61 -65)", "instruments": null, "is_usap_dc": true, "keywords": "Marguerite Bay; USA/NSF; AMD; Weddell Sea; USAP-DC; FIELD SURVEYS; Amd/Us; MARINE ECOSYSTEMS; ANIMALS/INVERTEBRATES", "locations": "Weddell Sea; Marguerite Bay", "north": -61.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Halanych, Kenneth; Mahon, Andrew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -69.0, "title": "Collaborative Research: Have transantarctic dispersal corridors impacted Antarctic marine biodiversity?", "uid": "p0010266", "west": -72.0}, {"awards": "2049332 Chu, Wing Yin", "bounds_geometry": "POLYGON((-180 -75,-175 -75,-170 -75,-165 -75,-160 -75,-155 -75,-150 -75,-145 -75,-140 -75,-135 -75,-130 -75,-130 -76.1,-130 -77.2,-130 -78.3,-130 -79.4,-130 -80.5,-130 -81.6,-130 -82.7,-130 -83.8,-130 -84.9,-130 -86,-135 -86,-140 -86,-145 -86,-150 -86,-155 -86,-160 -86,-165 -86,-170 -86,-175 -86,180 -86,177.5 -86,175 -86,172.5 -86,170 -86,167.5 -86,165 -86,162.5 -86,160 -86,157.5 -86,155 -86,155 -84.9,155 -83.8,155 -82.7,155 -81.6,155 -80.5,155 -79.4,155 -78.3,155 -77.2,155 -76.1,155 -75,157.5 -75,160 -75,162.5 -75,165 -75,167.5 -75,170 -75,172.5 -75,175 -75,177.5 -75,-180 -75))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 15 Sep 2021 00:00:00 GMT", "description": "Ice shelves play a critical role in restricting the seaward flow of grounded ice by providing buttressing at their bases and sides. Processes that affect the long-term stability of ice shelves can therefore impact the future contribution of the Antarctic Ice Sheet to global sea-level rise. Ross Ice Shelf is the largest ice shelf on Earth, and it buttresses massive areas of West and East Antarctica. Previous studies of modern ice velocity indicate that Ross Ice Shelf\u2019s mass loss is roughly balanced by its mass gain. However, more recent remote sensing observations extended further back in time reveal the ice shelf is likely not in steady-state, including possible long-term thinning since the late 90s. Therefore, to accurately interpret modern days ice shelf changes, long-term observations are critical to evaluate how these short-term variations fit into the historical context of ice shelf variability. This project examines over four decades (1971 \u2013 2017) of historical and modern airborne radar sounding observations of the Ross Ice Shelf to investigate ice-shelf changes on the decadal timescales. The researchers will process, calibrate, and analyze radar data collected during the 1971-79 SPRI/NSF/TUD campaign and compare them against modern observations from both the 2011-17 NASA Operation IceBridge/NSF CReSIS and the 2015-17 ROSETTA-Ice surveys. They will estimate basal melt rates by examining changes in ice-shelf thickness. They will determine other important basal melt metrics, including ice shelf roughness, englacial temperature, and marine ice formation. This project will support the education of a Ph.D. student from each of the institutions. This project will also support the training of undergraduate and high school researchers more generally in the field of radioglaciology and Antarctic sciences.", "east": -130.0, "geometry": "POINT(-167.5 -80.5)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; Antarctic Ice Sheet; GLACIER THICKNESS/ICE SHEET THICKNESS; USAP-DC; AMD; Transantarctic Mountains; Amd/Us; Siple Coast; GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHY; FIELD SURVEYS; USA/NSF; Ross Ice Shelf", "locations": "Ross Ice Shelf; Antarctic Ice Sheet; Siple Coast; Transantarctic Mountains", "north": -75.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Chu, Winnie; Siegfried, Matt; Schroeder, Dustin", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -86.0, "title": "Collaborative Research: Investigating Four Decades of Ross Ice Shelf Subsurface Change with Historical and Modern Radar Sounding Data", "uid": "p0010265", "west": 155.0}, {"awards": "1656126 Koppers, Anthony", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "OSU Marine and Geology Repository", "datasets": [{"dataset_uid": "200245", "doi": null, "keywords": null, "people": null, "repository": "OSU-MGR", "science_program": null, "title": "OSU Marine and Geology Repository", "url": "https://osu-mgr.org/"}], "date_created": "Fri, 10 Sep 2021 00:00:00 GMT", "description": "Nontechnical Description\r\n\r\nThe Antarctic core collection, curated at Florida State University since 1963, is one of the world\u0027s premier marine geology collections. Consisting of irreplaceable sediment cores, this archive has greatly advanced the understanding of the Earth system, past and present, and will remain critical to future studies of the Earth. Given Oregon State University\u0027s (OSU) leadership in marine research and long track record providing state-of-the-art curatorial services through the OSU Marine and Geology Repository, this facility will provide world-class curatorial stewardship of the Antarctic core collection for decades to come. The Antarctic core collection will be co-located and co-managed with the current OSU collection in a single modern repository and analytical facility. The combined collection will contain more than 30 km of refrigerated sediment core from the world\u0027s oceans and will be housed in a new 33,000 SFT facility purchased in 2009 by OSU and upgraded in 2016-17. The total refrigerated space can hold both collections comfortably and has at least five decades of expansion space.\r\n\r\nThe co-location and co-management of these two collections, paired with a modern suite of analytical facilities, will lead to greater collaboration, cross-pollination of ideas, and availability of enhanced technical services and capabilities for a growing user group that increasingly relies on marine sediments. The facility will employ a comprehensive community interaction plan that takes advantage of the new OSU Marine and Geology Repository building with a 32-person seminar room, its large 1,044 square foot core lab, and ten adjoining analytical laboratories, which will provide scientific and experiential learning opportunities for students, the general public, and the Earth Sciences research community. The facility will organize small group meetings, sampling parties and summer schools that will complement ongoing support for teaching, training and learning through the use of the repository in graduate, undergraduate, and K-12 classes and Research Experience for Undergraduate programs. The repository is open to the general public for tours and presentations, and the data products derived from the facility will be disseminated via the repository website at http://osu-mgr.org/ and other national databases.\r\n\r\nTechnical Description\r\n\r\nThe Antarctic and the Southern Ocean National Collection of Rock and Sediment Cores currently housed at Florida State University will be relocated to Oregon State University (OSU) and housed along with the OSU Marine and Geology Repository. Oregon State University investigators will co-manage the Antarctic core collection and the Marine and Geology Repository as a single modern repository and analytical facility. The combined collection will be housed a new 33,000 square foot building with refrigerated space that can hold both collections with approximately five decades of expansion space. The co-location and co-management of these two collections offers unique curatorial synergies, cost savings, and improved capabilities to support both the research and educational needs of a wider marine and Antarctic communities. The facility will house a 32-person seminar room, a large 1,044 square foot core lab that allows layout, inspection and examination of cores, and adjoining analytical laboratories that will provide quantitative analysis as well as experiential learning opportunities for students.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": true, "keywords": "Dredge Samples; MARINE SEDIMENTS; Amd/Us; AMD; SHIPS; USAP-DC; Antarctica; USA/NSF; Sediment Core", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Instrumentation and Support", "paleo_time": null, "persons": "Koppers, Anthony; Stoner, Joseph", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "OSU-MGR", "repositories": "OSU-MGR", "science_programs": null, "south": -90.0, "title": "Curatorial Stewardship of the Antarctic and the Southern Ocean National Collection of Rock and Sediment Cores at the OSU Marine and Geology Repository", "uid": "p0010262", "west": -180.0}, {"awards": "2046240 Khan, Alia", "bounds_geometry": "POLYGON((-75 -62,-73.5 -62,-72 -62,-70.5 -62,-69 -62,-67.5 -62,-66 -62,-64.5 -62,-63 -62,-61.5 -62,-60 -62,-60 -62.85,-60 -63.7,-60 -64.55,-60 -65.4,-60 -66.25,-60 -67.1,-60 -67.95,-60 -68.8,-60 -69.65,-60 -70.5,-61.5 -70.5,-63 -70.5,-64.5 -70.5,-66 -70.5,-67.5 -70.5,-69 -70.5,-70.5 -70.5,-72 -70.5,-73.5 -70.5,-75 -70.5,-75 -69.65,-75 -68.8,-75 -67.95,-75 -67.1,-75 -66.25,-75 -65.4,-75 -64.55,-75 -63.7,-75 -62.85,-75 -62))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 10 Sep 2021 00:00:00 GMT", "description": "Rapid and persistent climate warming in the Western Antarctic Peninsula is likely resulting in intensified snow-algae growth and an extended bloom season in coastal areas. Similarly, deposition of light absorbing particles (LAPs) onto Antarctica cryosphere surfaces, such as black carbon from intensifying Southern Hemisphere wildfire seasons, and dust from the expansion of ice-free regions in the Antarctic Peninsula, may be increasing. The presence of snow algae blooms and LAPs enhance the absorption of solar radiation by snow and ice surfaces. This positive feedback creates a measurable radiative forcing, which can have immediate local and long-term regional impacts on albedo, snow melt and downstream ecosystems. This project will investigate the spatial and temporal distribution of snow algae, black carbon and dust across the Western Antarctica Peninsula region, their response to climate warming, and their role in regional snow and ice melt. Data will be collected across multiple spatial scales from in situ field measurements and sample collection to imagery from ground-based photos and high resolution multi-spectral satellite sensors. Ground measurements will inform development and application of novel algorithms to map algal bloom extent through time using 0.5-3m spatial resolution multi-spectral satellite imagery. Results will be used to improve snow algae parameterization in a new version of the Snow Ice Aerosol Radiation model (SNICARv3) that includes bio-albedo feedbacks, eventually informing models of ice-free area expansion through incorporation of SNICARv3 in the Community Earth System Model. Citizen scientists will be mentored and engaged in the research through an active partnership with the International Association of Antarctic Tour Operators that frequently visits the region. The cruise ship association will facilitate sampling to develop a unique snow algae observing network to validate remote sensing algorithms that map snow algae with high-resolution multi-spectral satellite imagery from space. These time-series will inform instantaneous and interannual radiative forcing calculations to assess impacts of snow algae and LAPs on regional snow melt. Quantifying the spatio-temporal growing season of snow algae and impacts from black carbon and dust will increase our ability to model their impact on snow melt, regional climate warming and ice-free expansion in the Antarctic Peninsula region.", "east": -60.0, "geometry": "POINT(-67.5 -66.25)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; Antarctic Peninsula; Amd/Us; AMD; SNOW/ICE CHEMISTRY; USA/NSF; USAP-DC; SNOW", "locations": "Antarctic Peninsula", "north": -62.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Khan, Alia", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -70.5, "title": "CAREER: Coastal Antarctic Snow Algae and Light Absorbing Particles: Snowmelt, Climate and Ecosystem Impacts", "uid": "p0010263", "west": -75.0}, {"awards": "2114786 Warnock, Jonathan", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 09 Sep 2021 00:00:00 GMT", "description": "The potential for future sea level rise from melting and collapse of Antarctic ice sheets and glaciers is concerning. We can improve our understanding of how water is exchanged between Antarctic ice sheets and the ocean by studying how ice sheets behaved in past climates, especially conditions that were similar to or warmer than those at present. For this project, the research team will document Antarctica\u2019s response across an interval when Earth transitioned from the warm Pliocene into the Pleistocene ice ages by combining marine and land evidence for glacier variations from sites near the Antarctic Peninsula, complimented by detailed work on timescales and fossil evidence for environmental change. An important goal is to test whether Antarctica\u2019s glaciers changed at the same time as glaciers in the Northern Hemisphere as Earth\u0027s most recent Ice Age intensified, or alternatively responded to regional climate forcing in the Southern Hemisphere. Eleven investigators from seven US institutions, as well as Argentine collaborators, will study new sediment cores from the International Ocean Discovery Program, as well as legacy cores from that program and on-land outcrops on James Ross Island. The group embraces a vertically integrated research program that allows high school, undergraduate, graduate, post-docs and faculty to work together on the same projects. This structure leverages the benefits of near-peer mentoring and the development of a robust collaborative research network while allowing all participants to take ownership of different parts of the project. All members of the team are firmly committed to attracting researchers from under-represented groups and will do this through existing channels as well as via co-creating programming that centers the perspectives of diverse students in conversations about sea-level rise and climate change.\r\nThe proposed research seeks to understand phasing between Northern and Southern Hemisphere glacier and climate changes, as a means to understand drivers and teleconnections. The dynamics of past Antarctic glaciation can be studied using the unique isotope geochemical and mineralogic fingerprints from glacial sectors tied to a well-constrained time model for the stratigraphic successions. The proposed work would further refine the stratigraphic context through coupled biostratigraphic and magnetostratigraphic work. The magnitude of iceberg calving and paths of icebergs will be revealed using the flux, geochemical and mineralogic signatures, and 40Ar/39Ar and U-Pb geochronology of ice-rafted detritus. These provenance tracers will establish which sectors of Antarctica\u2019s ice sheets are more vulnerable to collapse, and the timing and pacing of these events will be revealed by their stratigraphic context. Additionally, the team will work with Argentine collaborators to connect the marine and terrestrial records by studying glacier records intercalated with volcanic flows on James Ross Island. These new constraints will be integrated with a state of the art ice-sheet model to link changes in ice dynamics with their underlying causes. Together, these tight stratigraphic constraints, geochemical signatures, and ice-sheet model simulations will provide a means to compare to the global records of climate change, understand their primary drivers, and elucidate the role of the Antarctic ice sheet in a major, global climatic shift from the Pliocene into the Pleistocene.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "MICROFOSSILS; FIELD SURVEYS; Weddell Sea Embayment; USA/NSF; SEA ICE; USAP-DC; PALEOCLIMATE RECONSTRUCTIONS; SEA SURFACE TEMPERATURE; AMD; Amd/Us", "locations": "Weddell Sea Embayment", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Warnock, Jonathan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Linking Marine and Terrestrial Sedimentary Evidence for Plio-pleistocene Variability of Weddell Embayment and Antarctic Peninsula Glaciation", "uid": "p0010260", "west": null}, {"awards": "2039432 Grapenthin, Ronni", "bounds_geometry": "POLYGON((165.5 -77.1,165.91 -77.1,166.32 -77.1,166.73 -77.1,167.14 -77.1,167.55 -77.1,167.96 -77.1,168.37 -77.1,168.78 -77.1,169.19 -77.1,169.6 -77.1,169.6 -77.18,169.6 -77.26,169.6 -77.34,169.6 -77.42,169.6 -77.5,169.6 -77.58,169.6 -77.66,169.6 -77.74,169.6 -77.82,169.6 -77.9,169.19 -77.9,168.78 -77.9,168.37 -77.9,167.96 -77.9,167.55 -77.9,167.14 -77.9,166.73 -77.9,166.32 -77.9,165.91 -77.9,165.5 -77.9,165.5 -77.82,165.5 -77.74,165.5 -77.66,165.5 -77.58,165.5 -77.5,165.5 -77.42,165.5 -77.34,165.5 -77.26,165.5 -77.18,165.5 -77.1))", "dataset_titles": "Erebus GPS timeseries ", "datasets": [{"dataset_uid": "601471", "doi": "10.15784/601471", "keywords": "Antarctica; GPS; Mount Erebus; Ross Island", "people": "Grapenthin, Ronni", "repository": "USAP-DC", "science_program": null, "title": "Erebus GPS timeseries ", "url": "https://www.usap-dc.org/view/dataset/601471"}], "date_created": "Fri, 03 Sep 2021 00:00:00 GMT", "description": "The project targets scientific questions recently formulated by the community during the 2016 NSF-sponsored Scientific Drivers and Future of Mount Erebus Volcano Observatory workshop. The location and geometry of the magmatic plumbing from vent to lower crust system remain poorly constrained, particularly below 1 km depth. The style and causes for changes in volcanic and magmatic activity over the short term (minutes to hours) and on the decadal scale remains enigmatic. Two decades of campaign and continuous GPS data on Ross Island provide insights into the longer term dynamics of both, Ross Island growing within the Terror Rift, and Erebus\u0027 deeper magmatic system. We organized and analyzed all existing GPS data for Ross Island, and interpreted anomalies in the resulting time series. The GPS data were consistently processed and interpreted. We generated position time series in a consistent reference frame and make the results available to the community. We find several periods of volcanic transient deformation in the time series, indicating times of inflation before 2004, deflation from 2004-2011 and renewed inflation from October 2020 until June 2021.", "east": 169.6, "geometry": "POINT(167.55 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Ross Island; TECTONICS; USAP-DC; Amd/Us; AMD; CRUSTAL MOTION; USA/NSF; FIELD SURVEYS", "locations": "Ross Island", "north": -77.1, "nsf_funding_programs": "Antarctic Instrumentation and Facilities; Antarctic Earth Sciences", "paleo_time": null, "persons": "Grapenthin, Ronni", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.9, "title": "Collaborative Research: Multi-Parameter Geophysical Constraints on Volcano Dynamics of Mt. Erebus and Ross Island, Antarctica", "uid": "p0010255", "west": 165.5}, {"awards": "2114839 Passchier, Sandra", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 25 Aug 2021 00:00:00 GMT", "description": "The project targets the long-term variability of the West Antarctic Ice Sheet over several glacial-interglacial cycles in the early Pliocene sedimentary record drilled by the International Ocean Discovery Program (IODP) Expedition 379 in the Amundsen Sea. Data collection includes 1) the sand provenance of ice-rafted debris and shelf diamictites and its sources within the Amundsen Sea and Antarctic Peninsula region; 2) sedimentary structures and sortable silt calculations from particle size records and reconstructions of current intensities and interactions; and 3) the bulk provenance of continental rise sediments compared to existing data from the Amundsen Sea shelf with investigations into downslope currents as pathways for Antarctic Bottom Water formation. The results are analyzed within a cyclostratigraphic framework of reflectance spectroscopy and colorimetry (RSC) and X-ray fluorescence scanner (XRF) data to gain insight into orbital forcing of the high-latitude processes. The early Pliocene Climatic Optimum (PCO) ~4.5-4.1 Ma spans a major warm period recognized in deep-sea stable isotope and sea-surface temperature records. This period also coincides with a global mean sea level highstand of \u003e 20 m requiring contributions in ice mass loss from Antarctica. The following hypotheses will be tested: 1) that the West Antarctic Ice Sheet retreated from the continental shelf break through an increase in sub iceshelf melt and iceberg calving at the onset of the PCO ~4.5 Ma, and 2) that dense shelf water cascaded down through slope channels after ~4.5 Ma as the continental shelf became exposed during glacial terminations. The project will reveal for the first time how the West Antarctic Ice Sheet operated in a warmer climate state prior to the onset of the current \u201cicehouse\u201d period ~3.3 Ma.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; TERRIGENOUS SEDIMENTS; Amd/Us; SEDIMENTS; FIELD SURVEYS; Amundsen Sea; USAP-DC; AMD", "locations": "Amundsen Sea", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Passchier, Sandra", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "West Antarctic Ice-sheet Change and Paleoceanography in the Amundsen Sea Across the Pliocene Climatic Optimum", "uid": "p0010252", "west": null}, {"awards": "2046800 Thurber, Andrew", "bounds_geometry": "POLYGON((162 -77,162.6 -77,163.2 -77,163.8 -77,164.4 -77,165 -77,165.6 -77,166.2 -77,166.8 -77,167.4 -77,168 -77,168 -77.1,168 -77.2,168 -77.3,168 -77.4,168 -77.5,168 -77.6,168 -77.7,168 -77.8,168 -77.9,168 -78,167.4 -78,166.8 -78,166.2 -78,165.6 -78,165 -78,164.4 -78,163.8 -78,163.2 -78,162.6 -78,162 -78,162 -77.9,162 -77.8,162 -77.7,162 -77.6,162 -77.5,162 -77.4,162 -77.3,162 -77.2,162 -77.1,162 -77))", "dataset_titles": null, "datasets": null, "date_created": "Sat, 21 Aug 2021 00:00:00 GMT", "description": "Due to persistent cold temperatures, geographical isolation, and resulting evolutionary distinctness of Southern Ocean fauna, the study of Antarctic reducing habitats has the potential to fundamentally alter our understanding of the biologic processes that inhibit greenhouse gas emissions from our oceans. Marine methane, a greenhouse gas 25x as potent as carbon dioxide for warming our atmosphere, is currently a minor component of atmospheric forcing due to the microbial oxidation of methane within the oceans. Based on studies of persistent deep-sea seeps at mid- and northern latitudes we have learned that bacteria and archaea create a \u2018sediment filter\u2019 that oxidizes methane prior to its release. As increasing global temperatures have and will continue to alter the rate and variance of methane release, the ability of the microbial filter to respond to fluctuations in methane cycles is a critical yet unexplored avenue of research. Antarctica contains vast reservoirs of methane, equivalent to all of the permafrost in the Arctic, and yet we know almost nothing about the fauna that may mitigate its release, as until recently, we had not discovered an active methane seep.\r\n\r\nIn 2012, a methane seep was discovered in the Ross Sea, Antarctica that formed in 2011 providing the first opportunity to study an active Antarctic methane-fueled habitat and simultaneously the impact of microbial succession on the oxidation of methane, a critical ecosystem service. Previous work has shown that after 5 years of seepage, the community was at an early stage of succession and unable to mitigate the release of methane from the seafloor. In addition, additional areas of seepage had begun nearby. This research aims to quantify the community trajectory of these seeps in relation to their role in the Antarctic Ecosystem, from greenhouse gas mitigation through supporting the food web. Through the application of genomic and transcriptomic approaches, taxa involved in methane cycling and genes activated by the addition of methane will be identified and contrasted with those from other geographical locations. These comparisons will elucidate how taxa have evolved and adapted to the polar environment.\r\n\r\nThis research uses a \u2018genome to ecosystem\u2019 approach to advance our understanding of organismal and systems ecology in Antarctica. By quantifying the trajectory of community succession following the onset of methane emission, the research will decipher temporal shifts in biodiversity/ecosystem function relationships. Phylogenomic approaches focusing on taxa involved in methane cycling will advance the burgeoning field of microbial biogeography on a continent where earth\u2019s history may have had a profound yet unquantified impact on microbial evolution. Further, the research will empirically quantify the role of chemosynthesis as a form of export production from seeps and in non-seep habitats in the nearshore Ross Sea benthos, informing our understanding of Antarctic carbon cycling.\r\n", "east": 168.0, "geometry": "POINT(165 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; USA/NSF; USAP-DC; BACTERIA/ARCHAEA; McMurdo Sound; BENTHIC; FIELD SURVEYS; Amd/Us; ECOSYSTEM FUNCTIONS", "locations": "McMurdo Sound", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Thurber, Andrew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -78.0, "title": "CAREER: Ecosystem Impacts of Microbial Succession and Production at Antarctic Methane Seeps", "uid": "p0010250", "west": 162.0}, {"awards": "1341649 Johnson, Leah; 1740239 Johnson, Leah", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 13 Aug 2021 00:00:00 GMT", "description": "Albatrosses (family Diomedeidae) are among the most threatened of bird species. Of the 22 species that are currently recognized, all are considered at least Threatened or Near-Threatened, and 9 are listed as Endangered or Critically Endangered. Because of the decline in albatross populations and the birds\u0027 role as a top predator in the pelagic ecosystem, it is vitally important to understand the factors affecting the population dynamics of these birds to better inform strategies for conservation and mitigating environmental change. The goal of this project is to answer the question: What are the population consequences of albatross bioenergetics and foraging strategies? The project took a two pronged approach: 1) constructing, parameterizing, and validating a Dynamic Energy Budget model to understand growth and constraints on foraging; and 2) undertaking an in-depth meta-analysis of existing individual tracking and life history data from multiple albatross species across successive life stages. This theoretical work will be grounded with a unique and extensive data set on albatrosses provided by collaborator Richard Phillips from the British Antarctic Survey. Bioenergetics constrain a variety of behaviors. A more complete understanding of how individuals use energy can give insight into how behaviors from foraging to breeding and survival, and resulting population attributes, might change with environmental factors, due to anthropogenic and other drivers. This work will further a general understanding of how bioenergetics shapes behavior and drives population level processes, while providing an approach that can be used to guide conservation strategies for endangered populations. The research findings and activities were made accessible to public audiences through websites and a blog maintained for the project by a postdoctoral researcher. The project involved undergraduate researchers in the project, within formal laboratory groups and also through in-classroom presentations and activities. This project also involved public outreach through twitter and other venues. All project publications are open access, the resulting open source software was released to the public, and metadata and analyses are fully documented to promote further collaborative exploration of this system.\r\n\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "BIRDS; Amd/Us; USAP-DC; AMD; USA/NSF; MODELS; United States Of America", "locations": "United States Of America", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Johnson, Leah; Ryan, Sadie", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Quantifying how Bioenergetics and Foraging Determine Population Dynamics in Threatened Antarctic Albatrosses", "uid": "p0010242", "west": -180.0}, {"awards": "1744999 Todgham, Anne", "bounds_geometry": "POLYGON((162 -77,162.8 -77,163.6 -77,164.4 -77,165.2 -77,166 -77,166.8 -77,167.6 -77,168.4 -77,169.2 -77,170 -77,170 -77.1,170 -77.2,170 -77.3,170 -77.4,170 -77.5,170 -77.6,170 -77.7,170 -77.8,170 -77.9,170 -78,169.2 -78,168.4 -78,167.6 -78,166.8 -78,166 -78,165.2 -78,164.4 -78,163.6 -78,162.8 -78,162 -78,162 -77.9,162 -77.8,162 -77.7,162 -77.6,162 -77.5,162 -77.4,162 -77.3,162 -77.2,162 -77.1,162 -77))", "dataset_titles": "A comparative and ontogenetic examination of mitochondrial function in Antarctic notothenioid species; Differential temperature preferences exhibited in the juvenile Antarctic notothenioids Trematomus bernacchii and Trematomus pennellii", "datasets": [{"dataset_uid": "601766", "doi": null, "keywords": "Antarctica; McMurdo Sound", "people": "Mandic, Milica; Naslund, Andrew; Todgham, Anne; Frazier, Amanda", "repository": "USAP-DC", "science_program": null, "title": "A comparative and ontogenetic examination of mitochondrial function in Antarctic notothenioid species", "url": "https://www.usap-dc.org/view/dataset/601766"}, {"dataset_uid": "601765", "doi": null, "keywords": "Antarctica; McMurdo Sound; Ross Sea", "people": "Mandic, Milica; Frazier, Amanda; Todgham, Anne; Naslund, Andrew; Zillig, Ken", "repository": "USAP-DC", "science_program": null, "title": "Differential temperature preferences exhibited in the juvenile Antarctic notothenioids Trematomus bernacchii and Trematomus pennellii", "url": "https://www.usap-dc.org/view/dataset/601765"}], "date_created": "Thu, 12 Aug 2021 00:00:00 GMT", "description": "This project fits within the second of three major themes identified by the National Academy of Science report \u201cA Strategic Vision for NSF Investments in Antarctic and Southern Ocean Research\u201d. How do Antarctic biota evolve and adapt to the changing environment? Decoding the genomic and transcriptomic bases of biological adaptation and response across Antarctic organisms and ecosystems. Central in this theme is the physiological capacity of animals to cope with changes in environmental conditions over their lifetime, which this research firmly addresses. In the Southern Ocean surrounding Antarctica there is an extraordinary diversity of marine life. Much of our understanding of the biology of these animals comes from studies of the adaptations of these animals to sub-zero ocean conditions. Antarctic marine organisms have evolved to survive in stable, cold ocean conditions and possess a limited capacity to respond to environmental change. Research to date on Antarctic fishes has focused on adult life stages with much less research on early life stages that likely prioritize growth and development and not physiological mechanisms of stress tolerance. This project addresses the mechanisms that early life stages (embryos, larvae and juveniles) of Antarctic fishes use to respond to changes in ocean conditions. Specifically, the project will examine energetic trade-offs between key developmental processes in the context of environmental change. While the project focuses on Antarctic species, the research is highly translatable to stress tolerance mechanisms of fishes along the coast of North America, many of which are also experiencing changes in multiple environmental factors. Research in the Antarctic allows scientists to identify unifying themes or generalities in physiology that extend beyond the waters of the Southern Ocean and therefore have broad implications for understanding what is limiting the performance of fishes globally. BROADER IMPACTS \u2013To build environmental stewardship and awareness, we must increase science literacy in the broader community. This project does this through three main objectives. First is to increase the diversity of students involved in environmental science research. Student diversity, in turn, gives the scientific community a broader perspective for addressing critical challenges in environmental biology. This project provides resources to support three PhD students, one postdoctoral scholar and two undergraduate students and promotes the diversity of young scientists and the advancement of groups traditionally underrepresented in environmental biology. Todgham will broaden the outreach effort by developing exhibits on environmental change impacts on polar regions for large public events, an opportunity to engage K-12 students, government officials in Sacramento and local and statewide communities. Lastly, through a collaboration with PolarTREC and teacher Denise Hardoy, lesson plans have been developed to teach K-12 students about experimental design, polar environments and sensitivity of Antarctic species to climate change.", "east": 170.0, "geometry": "POINT(166 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; AMD; McMurdo Sound; FISH; USA/NSF; Amd/Us; USAP-DC", "locations": "McMurdo Sound", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Todgham, Anne", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Interacting Stressors: Metabolic Capacity to Acclimate under Ocean Warming and CO2- Acidification in Early Developmental Stages of Antarctic Fishes", "uid": "p0010241", "west": 162.0}, {"awards": "1927709 Friedlaender, Ari; 1947453 Hunt, Kathleen; 1927742 Fleming, Alyson", "bounds_geometry": "POLYGON((150 -60,153 -60,156 -60,159 -60,162 -60,165 -60,168 -60,171 -60,174 -60,177 -60,180 -60,180 -61.5,180 -63,180 -64.5,180 -66,180 -67.5,180 -69,180 -70.5,180 -72,180 -73.5,180 -75,177 -75,174 -75,171 -75,168 -75,165 -75,162 -75,159 -75,156 -75,153 -75,150 -75,150 -73.5,150 -72,150 -70.5,150 -69,150 -67.5,150 -66,150 -64.5,150 -63,150 -61.5,150 -60))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 10 Aug 2021 00:00:00 GMT", "description": "An archive of baleen plates from 800 Antarctic blue and fin whales harvested between 1946 and 1948 was recently rediscovered in the Smithsonian\u2019s National Museum of Natural History. As baleen grows, it incorporates compounds from the whale\u2019s diet and surroundings, recording continuous biological and oceanographic information across multiple years. The baleen record forms an ideal experimental platform for studying bottom-up, top-down and anthropogenic impacts on blue and fin whales. Such insights are likely impossible to obtain through any other means as blue and fin whales now number ~1 and 4% of their pre-whaling abundances. The baleen archive includes years with strong climate and temperature anomalies allowing the influence of climate variability on predators and the ecosystems that support them to be examined. Additionally, the impact of whaling on whale stress levels will be investigated by comparing years of intensive whaling with the non-whaling years of WWII, both of which are captured in the time series. We will use 1) bulk stable isotopes to examine the trophic dynamics of Antarctic blue and fin whales, 2) compound-specific stable isotope analysis (CSIA-AA) to characterize the biogeochemistry of the base of the Antarctic food web and 3) hormone analyses to examine the population biology of these species. These investigations will fill major gaps in our understanding of the largest krill predators, their response to disturbance and environmental change, and the impact that commercial whaling has had on the structure and function of the Antarctic marine ecosystem.", "east": 180.0, "geometry": "POINT(165 -67.5)", "instruments": null, "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; PELAGIC; MAMMALS; LABORATORY; AMD; Amd/Us; Southern Ocean; USAP-DC; USA/NSF", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Fleming, Alyson; Friedlaender, Ari; McCarthy, Matthew; Hunt, Kathleen", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -75.0, "title": "Collaborative Research: A New Baseline for Antarctic Blue and Fin Whales", "uid": "p0010240", "west": 150.0}, {"awards": "2031442 Learman, Deric", "bounds_geometry": "POLYGON((-180 -60,-167.5 -60,-155 -60,-142.5 -60,-130 -60,-117.5 -60,-105 -60,-92.5 -60,-80 -60,-67.5 -60,-55 -60,-55 -62,-55 -64,-55 -66,-55 -68,-55 -70,-55 -72,-55 -74,-55 -76,-55 -78,-55 -80,-67.5 -80,-80 -80,-92.5 -80,-105 -80,-117.5 -80,-130 -80,-142.5 -80,-155 -80,-167.5 -80,180 -80,178 -80,176 -80,174 -80,172 -80,170 -80,168 -80,166 -80,164 -80,162 -80,160 -80,160 -78,160 -76,160 -74,160 -72,160 -70,160 -68,160 -66,160 -64,160 -62,160 -60,162 -60,164 -60,166 -60,168 -60,170 -60,172 -60,174 -60,176 -60,178 -60,-180 -60))", "dataset_titles": "Physical and geochemical data from shelf sediments near the Antartic Pennisula", "datasets": [{"dataset_uid": "601607", "doi": "10.15784/601607", "keywords": "Antarctica; Antarctic Peninsula; Grain Size; Grain Size Analysis; Marine Geoscience; Marine Sediments; Organic Matter Geochemistry; Sediment Core Data; Shelf Sediments; Weddell Sea", "people": "Learman, Deric", "repository": "USAP-DC", "science_program": null, "title": "Physical and geochemical data from shelf sediments near the Antartic Pennisula", "url": "https://www.usap-dc.org/view/dataset/601607"}], "date_created": "Wed, 28 Jul 2021 00:00:00 GMT", "description": "This proposal will provide genetic and enzymatic insight into how microbial communities in benthic sediments on the coastal shelf of Antarctica degrade complex organic matter. The current understanding of how benthic microbial communities respond and also degrade complex organic matter in Antarctica is fragmented. Recent work suggests benthic microbial communities are shaped by organic matter availability (encompassing both quantity and quality), however, these studies were observational and did not directly examine community function (e.g. enzyme activity and/or gene expression). Preliminary metagenomic data, collected from western Antarctica marine sediments, document gene potential for organic matter degradation throughout the entire sample set (spanning the Amundsen Sea, Bellingshausen Sea, and Ross Sea), but functional data was not collected. To date, studies have examined either enzyme activity or metagenomic potential but few have been able to directly connect the two. To address these gaps in knowledge, this proposal will utilize powerful tools such as metagenomics and metatranscriptomics, coupled with microcosm experiments, enzyme assays, and geochemical data. This hypothesis driven proposal will examine microbial communities from the continental shelf of Antarctica from two different regions (Bransfield Strait and Weddell Sea) to document the communities\u2019 enzymatic activity and genes used to degrade complex organic matter. These data will expand our current knowledge of genetic potential towards a more direct understanding of enzyme function as it relates to degradation of complex organic matter in marine sediments from Antarctica. ", "east": 160.0, "geometry": "POINT(-127.5 -70)", "instruments": null, "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; USAP-DC; Antarctic Peninsula; BENTHIC; SHIPS; SEDIMENT CHEMISTRY; Amd/Us; AMD; USA/NSF; Weddell Sea", "locations": "Antarctic Peninsula; Weddell Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Learman, Deric", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments", "uid": "p0010235", "west": -55.0}, {"awards": "1943550 McDonald, Birgitte", "bounds_geometry": "POLYGON((168 -77,168.3 -77,168.6 -77,168.9 -77,169.2 -77,169.5 -77,169.8 -77,170.1 -77,170.4 -77,170.7 -77,171 -77,171 -77.1,171 -77.2,171 -77.3,171 -77.4,171 -77.5,171 -77.6,171 -77.7,171 -77.8,171 -77.9,171 -78,170.7 -78,170.4 -78,170.1 -78,169.8 -78,169.5 -78,169.2 -78,168.9 -78,168.6 -78,168.3 -78,168 -78,168 -77.9,168 -77.8,168 -77.7,168 -77.6,168 -77.5,168 -77.4,168 -77.3,168 -77.2,168 -77.1,168 -77))", "dataset_titles": "Late chick-rearing foraging ecology of emperor penguins from the Cape Crozier colony; Post-molt emperor penguin foraging ecology", "datasets": [{"dataset_uid": "601688", "doi": "10.15784/601688", "keywords": "Animal Tracking; Antarctica; Biota; Emperor Penguin; GPS; Late Chick Rearing; Ross Sea", "people": "McDonald, Birgitte", "repository": "USAP-DC", "science_program": null, "title": "Late chick-rearing foraging ecology of emperor penguins from the Cape Crozier colony", "url": "https://www.usap-dc.org/view/dataset/601688"}, {"dataset_uid": "601686", "doi": "10.15784/601686", "keywords": "Antarctica; Biota; Emperor Penguin; NBP2302; Post-Molt; Ross Sea", "people": "McDonald, Birgitte", "repository": "USAP-DC", "science_program": null, "title": "Post-molt emperor penguin foraging ecology", "url": "https://www.usap-dc.org/view/dataset/601686"}], "date_created": "Tue, 20 Jul 2021 00:00:00 GMT", "description": "This project will identify behavioral and physiological variability in foraging Emperor Penguins that can be directly linked to individual success in the marine environment using an optimal foraging theory framework during two critical life history stages. First, this project will investigate the foraging energetics, ecology, and habitat use of Emperor Penguins at Cape Crozier using fine-scale movement and video data loggers during late chick-rearing, an energetically demanding life history phase. Specifically, this study will 1) Estimate the foraging efficiency and examine its relationship to foraging behavior and diet using an optimal foraging theory framework to identify what environmental or physiological constraints influence foraging behavior; 2) Investigate the inter- and intra-individual behavioral variability exhibited by emperor penguins, which is essential to predict how resilient they will be to climate change; and 3) Integrate penguin foraging efficiency data with environmental data to identify important habitat. Next the researchers will study the ecology and habitat preference after the molt and through early reproduction using satellite-linked data loggers. The researchers will: 1) Investigate the inter- and intra-individual behavioral variability exhibited by Emperor Penguins during the three-month post-molt and early winter foraging trips; and 2) Integrate penguin behavioral data with environmental data to identify which environmental features are indicative of habitat preference when penguins are not constrained to returning to the colony to feed a chick. These fine- and coarse-scale data will be combined with climate predictions to create predictive habitat models. The education objectives of this CAREER project are designed to inspire, engage, and train the next generation of scientists using the data and video generated while investigating Emperor Penguins in the Antarctic ecosystem. This includes development of two courses (general education and advanced techniques), training of undergraduate and graduate students, and a collaboration with the NSF funded \u201cPolar Literacy: A model for youth engagement and learning\u201d program to develop afterschool and camp curriculum that target underserved and underrepresented groups.\r\n\r\n", "east": 171.0, "geometry": "POINT(169.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; PENGUINS; MARINE ECOSYSTEMS; USA/NSF; Ross Sea; FIELD SURVEYS; USAP-DC; AMD", "locations": "Ross Sea", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "McDonald, Birgitte", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "CAREER: Foraging Ecology and Physiology of Emperor Penguins in the Ross Sea", "uid": "p0010232", "west": 168.0}, {"awards": "1744794 Jenouvrier, Stephanie; 1744989 LaRue, Michelle", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Detecting climate signals in populations: case of emperor penguin; Emperor penguin population trends (2009-2018); Landfast ice: a major driver of reproductive success in a polar seabird", "datasets": [{"dataset_uid": "601491", "doi": "10.15784/601491", "keywords": "Antarctica", "people": "Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Detecting climate signals in populations: case of emperor penguin", "url": "https://www.usap-dc.org/view/dataset/601491"}, {"dataset_uid": "601513", "doi": "10.15784/601513", "keywords": "Antarctica; Breeding Success; Emperor Penguin; Fast Sea Ice", "people": "Labrousse, Sara; Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Landfast ice: a major driver of reproductive success in a polar seabird", "url": "https://www.usap-dc.org/view/dataset/601513"}, {"dataset_uid": "200388", "doi": "", "keywords": null, "people": null, "repository": "Github", "science_program": null, "title": "Emperor penguin population trends (2009-2018)", "url": "https://github.com/davidiles/EMPE_Global"}], "date_created": "Wed, 14 Jul 2021 00:00:00 GMT", "description": "This project on emperor penguin populations will quantify penguin presence/absence, and colony size and trajectory, across the entire Antarctic continent using high-resolution satellite imagery. For a subset of the colonies, population estimates derived from high-resolution satellite images will be compared with those determined by aerial surveys - these results have been uploaded to MAPPPD (penguinmap.com) and are freely available for use. This validated information will be used to determine population estimates for all emperor penguin colonies through iterations of supervised classification and maximum likelihood calculations on the high-resolution imagery. The effect of spatial, geophysical, and environmental variables on population size and decadal-scale trends will be assessed using generalized linear models. This research will result in a first ever empirical result for emperor penguin population trends and habitat suitability, and will leverage currently-funded NSF infrastructure and hosting sites to publish results in near-real time to the public.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; Ross Sea; USAP-DC; AMD; COMMUNITY DYNAMICS; Amd/Us", "locations": "Ross Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "LaRue, Michelle; Ito, Emi; Jenouvrier, Stephanie", "platforms": null, "repo": "USAP-DC", "repositories": "Github; USAP-DC", "science_programs": null, "south": -90.0, "title": "A Multi-scale Approach to Understanding Spatial and Population Variability in Emperor Penguins", "uid": "p0010229", "west": -180.0}, {"awards": "2001430 Cassano, John", "bounds_geometry": "POLYGON((166 -77,166.4 -77,166.8 -77,167.2 -77,167.6 -77,168 -77,168.4 -77,168.8 -77,169.2 -77,169.6 -77,170 -77,170 -77.1,170 -77.2,170 -77.3,170 -77.4,170 -77.5,170 -77.6,170 -77.7,170 -77.8,170 -77.9,170 -78,169.6 -78,169.2 -78,168.8 -78,168.4 -78,168 -78,167.6 -78,167.2 -78,166.8 -78,166.4 -78,166 -78,166 -77.9,166 -77.8,166 -77.7,166 -77.6,166 -77.5,166 -77.4,166 -77.3,166 -77.2,166 -77.1,166 -77))", "dataset_titles": "Radar Data for Phoenix Airfield (NZFX), 2019", "datasets": [{"dataset_uid": "200358", "doi": "10.48567/wrfx-7c88", "keywords": null, "people": null, "repository": "AMRDC", "science_program": null, "title": "Radar Data for Phoenix Airfield (NZFX), 2019", "url": "https://amrdcdata.ssec.wisc.edu/dataset/radar-data-for-phoenix-airfield-nzfx-2019"}], "date_created": "Tue, 06 Jul 2021 00:00:00 GMT", "description": "The Ross Island region of Antarctica is a topographically complex region that results in large variations in the mesoscale high wind and precipitation features across the region. The goals of this project are to increase the understanding of the three-dimensional structure of these mesoscale meteorology features. This project will leverage observations from the scanning X-band radar installed during the AWARE field campaign in 2016 and the installation of an EWR Radar Systems X-band scanning radar (E700XD) to be deployed during the 2019-20 field season.\r\nIntellectual Merit:\r\nThe focus of the science will be on questions investigating the structure and forcing of mesoscale wind and precipitation features in the vicinity of McMurdo Station. In addition to the data from the X-band scanning radars, observations from surface-based automatic weather stations, radiosonde launches from McMurdo Station, the suite of AWARE observations, and archived forecasts from the Antarctic Mesoscale Prediction System will be used to provide verification and additional insights into the structure of these mesoscale features. The science questions to be addressed in this study are:\r\n- What are the signatures of the mesoscale high wind features that are detectable by a scanning X-band, Doppler radar that can be used to aid in operational forecasting and to increase lead time of high wind event warnings for improved safety and logistics in the Ross Island region?\r\n- How does the orientation of the mesoscale high wind events play a role in the determining the severity of the impacts of the high winds at logistically significant locations across the Ross Island region?\r\n- What is the distribution of precipitation across the Ross Island region? Are there local topographic features that result in banding of precipitation across the region?\r\n- What is the accuracy of AMPS in forecasting mesoscale precipitation and wind features across the Ross Island region during the main body season?\r\nBroader Impacts:\r\nThe benefits of this project will extend beyond that of addressing the science questions and into improvements and increased data resources for the logistics, operational forecasting and research communities.\r\n- Provide increased understanding and in-depth analysis of the mesoscale wind and precipitation features detectable using radar observations to be transferred to the NIWC forecasters resulting in increased awareness and training.\r\n- With the comparison of the capabilities of the AWARE radar to that of the EWR Radar Systems E700XD the USAP can make an informed decision for the future purchase of a similar or different radar system for long-term deployment and use in forecasting for the region.\r\n- Develop a robust and coordinated data archive of the EWR Radar Systems E700XD during the 2019-20 deployment to be shared and used by future research investigations.\r\n- Provide insight, tools, and an outline for additional studies based on the remote sensing dataset collected during the AWARE project.", "east": 170.0, "geometry": "POINT(168 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "SNOW; AMD; FIELD SURVEYS; Amd/Us; McMurdo; USAP-DC; USA/NSF; ATMOSPHERIC WINDS", "locations": "McMurdo", "north": -77.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Cassano, John; Seefeldt, Mark; Kingsmill, David", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "AMRDC", "repositories": "AMRDC", "science_programs": null, "south": -78.0, "title": "RAPID: An Improved Understanding of Mesoscale Wind and Precipitation Variability in the Ross Island Region Based on Radar Observations", "uid": "p0010226", "west": 166.0}, {"awards": "2000992 Romans, Brian", "bounds_geometry": "POINT(-172.873074 -74.274008)", "dataset_titles": "Grain size of Plio-Pleistocene continental slope and rise sediments, Hillary Canyon, Ross Sea", "datasets": [{"dataset_uid": "601807", "doi": "10.15784/601807", "keywords": "Antarctica; Cryosphere; Grain Size; Ross Sea", "people": "Varela, Natalia; Romans, Brian W.", "repository": "USAP-DC", "science_program": null, "title": "Grain size of Plio-Pleistocene continental slope and rise sediments, Hillary Canyon, Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601807"}], "date_created": "Tue, 06 Jul 2021 00:00:00 GMT", "description": "Geological records from the Antarctic Ice Sheet (AIS) margin demonstrate that the ice sheet oscillated in response to orbital variations in insolation (i.e., ~400, 100, 41, and 20 kyr), and it appears to be more sensitive to specific frequencies that regulate mean annual insolation (i.e., 41-kyr obliquity), particularly when the ice sheet extends into marine environments and is impacted by ocean circulation. However, the relationship between orbital forcing and the production of Antarctic Bottom Water (AABW) is unconstrained. Thus, a knowledge gap exists in understanding how changing insolation impacts ice marginal and Southern Ocean conditions that directly influence ventilation of the global ocean. We hypothesize that insolation-driven changes directly affected the production and export of AABW to the Southern Ocean from the Pliocene through the Pleistocene. For example, obliquity amplification during the warmer Pliocene may have led to enhanced production and export of dense waters from the shelf due to reduced AIS extent, which, in turn, led to greater AABW outflow. To determine the relationship of AABW production to orbital regime, we plan to reconstruct both from a single, continuous record from the levee of Hillary Canyon, a major conduit of AABW outflow, on the Ross Sea continental rise. \r\n\r\nTo test our hypothesis, we will analyze sediment from IODP Site U1524 (recovered in 2018 during International Ocean Discovery Program Expedition 374) and focus on three data sets. (1) We will use the occurrence, frequency, and character of mm-scale turbidite beds as a proxy of dense-shelf-water cascading outflow and AABW production. We will estimate the down-slope flux via numerical modeling of turbidity current properties using morphology, grain size, and bed thickness as input parameters. (2) We will use grain-size data, physical properties, XRF core scanning, CT imaging, and hyperspectral imaging to guide lithofacies analysis to infer processes occurring during glacial, deglacial, and interglacial periods. Statistical techniques and optimization methods will be applied to test for astronomical forcing of sedimentary packages in order to provide a cyclostratigraphic framework and interpret the orbital-forcing regime. (3) We will use bulk sedimentary carbon and nitrogen abundance and isotope data to determine how relative contributions of terrigenous and marine organic matter change in response to orbital forcing. We will integrate these data with sedimentological records to deconvolve organic matter production from its deposition or remobilization due to AABW outflow as a function of the oscillating extent of the AIS. These data sets will be integrated into a unified chronostratigraphy to determine the relationship between AABW outflow and orbital-forcing scenarios under the varying climate regimes of the Plio-Pleistocene.\r\n", "east": -172.873074, "geometry": "POINT(-172.873074 -74.274008)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; LABORATORY; AMD; USA/NSF; SEDIMENTS; Amd/Us; Ross Sea", "locations": "Ross Sea", "north": -74.274008, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Patterson, Molly; Ash, Jeanine; Kulhanek, Denise; Ash, Jeannie", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -74.274008, "title": "COLLABORATIVE RESEARCH: Orbital-scale Variability of the West Antarctic Ice Sheet and the Formation of Bottom Water in the Ross Sea during the Pliocene-Pleistocene", "uid": "p0010227", "west": -172.873074}, {"awards": "2023259 Thompson, Andrew; 2023303 Purkey, Sarah; 2023244 Stewart, Andrew", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Ocean CFC reconstructed data product", "datasets": [{"dataset_uid": "601752", "doi": "10.15784/601752", "keywords": "Antarctica; CFCs; GLODAP; Ocean Model; Ocean Ventilation; Southern Ocean", "people": "Gebbie, Jack; Cimoli, Laura; Purkey, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Ocean CFC reconstructed data product", "url": "https://www.usap-dc.org/view/dataset/601752"}], "date_created": "Thu, 01 Jul 2021 00:00:00 GMT", "description": "The formation of dense Antarctic Bottom Water (AABW) and its export northward from the Antarctic continent is one of the key components of the global ocean overturning circulation, and plays a critical role in regulating Earth\u0027s climate on multi-decadal-to-millennial time scales. Recent studies of the global ocean overturning circulation have increasingly emphasized its three-dimensional structure: AABW is produced in a handful of distinct sites around the Antarctic continent, and there is a pronounced asymmetry in the allocation of AABW transports into the Atlantic, Indian and Pacific basins. The connectivity of AABW between the Antarctic continental shelf and the northern basins is mediated by the Antarctic Circumpolar Current (ACC), a circumpolar eastward flow that also serves as the primary route for inter-basin exchange.\r\n\r\nThe mapping from different shelf AABW sources to the northern basins dictates the response of the global MOC to localized variability or shifts in the state of the Antarctic shelf, for example due to major glacier calving events or modified inputs of freshwater from the Antarctic ice sheet. At present this mapping is not well constrained, with conflicting conclusions drawn in previous studies: at one extreme the ACC has been suggested to be a ``conduit\u0027\u0027 that simply allows each variety of AABW to transit directly northward; at the other extreme, it has been suggested that the ACC ``blends\u0027\u0027 all shelf AABW sources together before they reach the northern basins. Such conflicts arise, in part, because little is understood about the physics that determines AABW\u0027s pathways across the ACC.\r\n\r\nTo close this gap in understanding, this collaborative project draws on three complementary analytical tools: process-oriented modeling of AABW export across the ACC, a high-resolution global ocean model, and an observationally-constrained estimate of the global circulation. The PIs will first identify and quantify the pathways of AABW across the ACC by using these tools to propagate passive tracers that identify each of the four major AABW formation sites. They will then use a suite of process model sensitivity experiments to develop a theory for what controls meridional versus inter-basin transport of AABW in the ACC, and transfer this theory to interpret the AABW pathways simulated in the global model. Finally, they will combine the process model, global model and the observationally-constrained circulation product to map the rates at which AABW is transformed into lighter waters, and relate these transformation rates to the diagnosed pathways of AABW across the ACC. This combination of approaches allow the PIs to not only constrain the three-dimensional circulation of AABW from Antarctica to the northern basins, but also provides a mechanistic understanding of the circulation that can be transferred to past or future climates.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e DATA ANALYSIS \u003e ENVIRONMENTAL MODELING \u003e COMPUTER", "is_usap_dc": true, "keywords": "AMD; MODELS; USAP-DC; WATER MASSES; Southern Ocean; Amd/Us; OCEAN CURRENTS; COMPUTERS; Antarctic Circumpolar Current; USA/NSF", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Stewart, Andrew; Thompson, Andrew; Purkey, Sarah", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e MODELS \u003e MODELS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: The Antarctic Circumpolar Current: A Conduit or Blender of Antarctic Bottom Waters?", "uid": "p0010220", "west": -180.0}, {"awards": "1643445 Eisenman, Ian", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Model code, model output fields, etc", "datasets": [{"dataset_uid": "200226", "doi": null, "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Model code, model output fields, etc", "url": "https://eisenman-group.github.io/"}], "date_created": "Wed, 30 Jun 2021 00:00:00 GMT", "description": "Satellite observations show expanding Antarctic sea ice over the last three decades. Increasing Antarctic sea ice seems unexpected when compared to observations of rising global temperatures or shrinking Arctic sea ice. Computer models of global climate also predict Antarctic sea ice to shrink instead of grow. Several hypotheses have been suggested to explain the contradiction between what scientists expect to see based on computer models and physical intuition and the growth that is recorded in observations. This study will examine the hypothesis that sea ice expansion can be explained by sea ice motion, where sea ice moves in such a way as to promote an increase in overall coverage. Researchers will use several different types of computer models, ranging in complexity, to better understand the physical processes of sea ice motion and how the sea ice motion interacts with the larger atmosphere-ocean system. The team will transfer their research to the classroom by hosting a week-long teacher workshop. Teachers will learn how scientists use computer models to test hypotheses and then develop and test tools for use in the classroom. Five middle and high school teachers will participate and become part of the UC San Diego STEM Success Initiative master science teacher network. The project will support a graduate student and a postdoctoral researcher.\r\n\r\nSea ice motion has recently emerged as one of the candidates to explain the Antarctic sea ice expansion but a systematic investigation of how sea ice motion influences sea ice concentration has not been presented to date. Researchers will conduct a process-oriented study of the relationship between sea ice motion and Antarctic sea ice extent using a hierarchy of models. The hierarchy will consist of (i) an idealized single-column model of sea ice evolution, (ii) an idealized latitudinally-varying global model of sea ice and climate, (iii) an atmospheric global climate model (GCM) above a slab ocean that includes sea ice motion, (iv) a comprehensive GCM, and (v) model output from the suite of current comprehensive GCMs. The range of model complexities will help researchers better understand the relationship between sea ice motion and sea ice extent by allowing them to identify important processes that are robust across the model hierarchy.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; AMD; Southern Ocean; USAP-DC; USA/NSF; ICE EXTENT; COMPUTERS; Sea Ice; GCM", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Eisenman, Ian; Wagner, Till", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS", "repo": "GitHub", "repositories": "GitHub", "science_programs": null, "south": -90.0, "title": "The Influence of Sea Ice Motion on Antarctic Sea Ice Expansion", "uid": "p0010216", "west": -180.0}, {"awards": "2027615 Paden, John", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 30 Jun 2021 00:00:00 GMT", "description": "This project will develop a new ice-penetrating radar system that can simultaneously map glacier geometry (three-dimensional ice-sheet internal architecture and subglacial topography) and glacier flow (vertical velocity of ice) along repeat profiles. Forecasting ice-sheet contribution to sea level requires an estimate for the initial ice-sheet geometry and the parameters that govern ice flow (ice rheology) and slip across bedrock (bed friction). Existing ice-sheet models cannot independently initialize ice rheology and bed friction from conventional observations of surface velocities and glacier geometry. These non-unique solutions for ice-sheet initial state introduce substantial uncertainty into ice-sheet model simulations of past and future ice-sheet behavior. \r\nSpatially-distributed vertical velocities of ice measured by this radar system can be directly compared to simulated vertical velocities produced by glacier models. Thus, this radar technology will allow ice rheology to be constrained independently from bed friction, leading to higher fidelity simulations of past and future ice-sheet behavior and more accurate projections of future sea level.\r\n\r\nThe new radar system will integrate two existing radars (the multi-channel coherent radio-echo depth sounder and the accumulation radar) developed by the Center for the Remote Sensing of Ice Sheets, but also includes new capabilities. An eight-element very high frequency (VHF; 140-215 MHz) array will have sufficient cross-track aperture to swath map internal layers and the ice-sheet base in three dimensions. A single ultra high frequency (UHF; 600-900 MHz) antenna will have the range and phase resolution to map internal layer displacement with 0.25 mm precision. The VHF array will create 3D mappings of layer geometry that enable measurements of vertical velocities by accounting for spatial offsets between repeat profiles and changing surface conditions. The vertical displacement measurement will then be made by determining the difference in radar phase response recorded by the UHF antenna for radar profiles collected at the same locations at different times. The UHF antenna will be dual-polarized and thus capable of isolating both components of complex internal reflections, which should enable inferences of ice crystal orientation fabric and widespread mapping of ice viscosity. Initial deployment of the radar will occur on the McMurdo Ice Shelf and Thwaites Glacier, Antarctica. The dual-band radar system technology and processing algorithms will be developed with versatile extensible hardware and user-friendly software, so that this system will serve as a prototype for a future community radar system.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e IMAGING RADAR SYSTEMS", "is_usap_dc": true, "keywords": "Amd/Us; USA/NSF; Airborne Radar; AMD; ICE SHEETS; Thwaites Glacier; USAP-DC", "locations": "Thwaites Glacier", "north": null, "nsf_funding_programs": "Antarctic Instrumentation and Facilities", "paleo_time": null, "persons": "Paden, John; Rodriguez-Morales, Fernando ", "platforms": null, "repositories": null, "science_programs": "Thwaites (ITGC)", "south": null, "title": "Collaborative Research: EAGER: A Dual-Band Radar for Measuring Internal Ice Deformation: a Multipass Ice-Penetrating Radar Experiment on Thwaites Glacier and the McMurdo Ice Shelf", "uid": "p0010215", "west": null}, {"awards": "1947094 Sidor, Christian", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 30 Jun 2021 00:00:00 GMT", "description": "The research supported by this grant centers on the evolution of fossil amphibians (temnospondyls) from the Early Triassic, a crucial time interval in the evolution of life on Earth following the end-Permian mass extinction, specifically based on fossil material from Antarctica, a high-latitude paleoenvironment that may have served as a refuge for tetrapods across the extinction event. Previous records of temnospondyls, mostly reported several decades ago, are highly fragmentary, and their original interpretations are considered dubious or demonstrably erroneous by contemporary workers. The Antarctic record of temnospondyls is of great import in understanding the biotic recovery in terrestrial environments for several reasons. Firstly, temnospondyls, like amphibians today, were highly speciose in the Triassic but were also some of the most susceptible to environmental perturbations and instability. Therefore, temnospondyls provide key insights into the paleoenvironmental conditions, either in place of or alongside other lines of data. Secondly, the record of temnospondyls from the Early Triassic is quite rich, but it is also restricted to a few densely sampled regions, such as the Karoo Basin of South Africa. In order to ascertain whether observed patterns such as an unusual abundance of small-bodied taxa or a lack of faunal overlap between different depositional basins (endemism) are real or merely artifactual, study of additional, less sampled regions takes on great import. Recent collection of substantial new temnospondyl material from several horizons in the Triassic exposure of Antarctica provides the requisite data to begin to address these questions. Finally, correlating the Triassic rocks of Antarctica with those of adjacent regions is largely reliant on comparisons of faunal assemblages. In particular, the middle Fremouw Formation, one of the horizons from which new temnospondyl material was collected, remains of uncertain relation and age due to the paucity of described material. ", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Temnospondyls; MACROFOSSILS; USA/NSF; FIELD SURVEYS; Permian Extinction; Triassic; Amd/Us; USAP-DC; AMD; ANIMALS/VERTEBRATES; Shackleton Glacier", "locations": "Shackleton Glacier", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e PALEOZOIC \u003e PERMIAN", "persons": "Sidor, Christian", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "A non-amniote perspective on the recovery from the end-Permian extinction at high latitudes: paleobiology of Early Triassic temnospondyls from Antarctica", "uid": "p0010217", "west": null}, {"awards": "2001033 Makovicky, Peter; 1341475 Smith, Nathan; 1341645 Makovicky, Peter; 1341376 Tabor, Neil; 1341304 Sidor, Christian", "bounds_geometry": "POLYGON((-180 -84,-178 -84,-176 -84,-174 -84,-172 -84,-170 -84,-168 -84,-166 -84,-164 -84,-162 -84,-160 -84,-160 -84.3,-160 -84.6,-160 -84.9,-160 -85.2,-160 -85.5,-160 -85.8,-160 -86.1,-160 -86.4,-160 -86.7,-160 -87,-162 -87,-164 -87,-166 -87,-168 -87,-170 -87,-172 -87,-174 -87,-176 -87,-178 -87,180 -87,178.5 -87,177 -87,175.5 -87,174 -87,172.5 -87,171 -87,169.5 -87,168 -87,166.5 -87,165 -87,165 -86.7,165 -86.4,165 -86.1,165 -85.8,165 -85.5,165 -85.2,165 -84.9,165 -84.6,165 -84.3,165 -84,166.5 -84,168 -84,169.5 -84,171 -84,172.5 -84,174 -84,175.5 -84,177 -84,178.5 -84,-180 -84))", "dataset_titles": "Lower Triassic Antarctic vertebrate fossils at Field Museum, Chicago, IL", "datasets": [{"dataset_uid": "601511", "doi": "10.15784/601511", "keywords": "Allan Hills; Antarctica; Fremouw Formation; Lystrosaurus; Permo-Triassic Extinction; Prolacerta; Sample Location; Thrinaxofon; Triassic", "people": "Makovicky, Peter", "repository": "USAP-DC", "science_program": null, "title": "Lower Triassic Antarctic vertebrate fossils at Field Museum, Chicago, IL", "url": "https://www.usap-dc.org/view/dataset/601511"}], "date_created": "Tue, 29 Jun 2021 00:00:00 GMT", "description": "This project will advance our understanding of Antarctic life during the Permian and Triassic. We will apply an interdisciplinary approach to address relationships between environmental change, faunal composition, and biogeographic patterns in the context of the high-latitude strata preserved in the Buckley and Fremouw formations in the Shackleton Glacier region. We will use multiple types of data to assess paleoenvironment, including: 1) paleosol morphology; 2) paleosol geochemistry; 3) pedogenic organic matter; and 4) fossil wood chronology and stable isotopes. The Fremouw Formation of Antarctica preserves the highest paleolatitude tetrapod fauna of the entire Triassic (~70\u00b0 S) and thus has the potential to shed important light on the evolution of polar life during the early Mesozoic. We will collect new fossils from known localities to understand the relationship between Antarctic and southern African tetrapod faunas. Furthermore, we will refine the stratigraphic, sedimentological, and geochronological framework for these Mesozoic faunas, which will include using U/Pb detrital zircon dating to provide the first dates for these vertebrate assemblages. In the lab, we will examine the biology of Triassic vertebrates from Antarctica by comparing their bone and tusk histology to conspecifics from lower paleolatitudes. In addition, we will test Bergmann\u2019s Rule with six species (viz. Lystrosaurus curvatus, L. maccaigi, L. murrayi, Prolacerta broomi, Procolophon trigoniceps, and Thrinaxodon liorhinus). The Early Triassic presents a unique opportunity to perform such investigations as there is no other geologic interval in which species occurring in Antarctica can be compared to conspecifics across a range of paleolatitudes.", "east": -160.0, "geometry": "POINT(-177.5 -85.5)", "instruments": null, "is_usap_dc": true, "keywords": "REPTILES; FIELD SURVEYS; USA/NSF; PALEOCLIMATE RECONSTRUCTIONS; Triassic; USAP-DC; TERRESTRIAL ECOSYSTEMS; MACROFOSSILS; Amd/Us; Fossils; Shackleton Glacier; LAND RECORDS; ANIMALS/VERTEBRATES; AMD", "locations": "Shackleton Glacier", "north": -84.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Sidor, Christian; Smith, Nathan; Makovicky, Peter; Tabor, Neil", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.0, "title": "Collaborative Research: Understanding the evolution of high-latitude Permo-Triassic paleoenvironments and their vertebrate communities", "uid": "p0010213", "west": 165.0}, {"awards": "1935635 Santagata, Scott; 1935672 Ryan, Joseph", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 28 Jun 2021 00:00:00 GMT", "description": "Understanding the genomic changes underlying adaptations to polar environments is critical for \r\npredicting how ecological changes will affect life in these fragile environments. Accomplishing these goals requires looking in detail at genome-scale data across a wide array of organisms in a phylogenetic framework. This study combines multifaceted computational and functional approaches that involves analyzing in the genic evolution of invertebrate organisms, known as the bryozoans or ectoprocts. In addition, the commonality of our results in other taxa will be tested by comparing the results to those produced from the previous and newly proposed workshops. Specific aims of this study include: 1) identifying genes involved in adaptation to Antarctic marine environments using transcriptomic and genomic data from bryozoans to test for positively selected genes in a phylogenetic framework, 2) experimentally testing identified candidate enzymes (especially those involved in calcium signaling, glycolysis, the citric acid cycle, and the cytoskeleton) for evidence of cold adaption, and 3) conducting computational workshops aimed at training scientists in techniques for the identification of genetic adaptations to polar and other disparate environments. The proposed work provides critical insights into the molecular rules of life in rapidly changing Antarctic environments, and provides important information for understanding how Antarctic taxa will respond to future environmental conditions.\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; USA/NSF; Ross Sea; Ant Lia; ANIMALS/INVERTEBRATES; FIELD SURVEYS; Weddell Sea; Bellingshausen Sea; Amundsen Sea; Antarctic Peninsula; Amd/Us; AMD", "locations": "Amundsen Sea; Antarctic Peninsula; Bellingshausen Sea; Ross Sea; Weddell Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ryan, Joseph; Santagata, Scott", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -90.0, "title": "ANT LIA Collaborative Research: Interrogating Molecular and Physiological Adaptations in Antarctic Marine Animals.", "uid": "p0010212", "west": -180.0}, {"awards": "1644159 Jacobs, Stanley", "bounds_geometry": "POLYGON((-180 -72.5,-177 -72.5,-174 -72.5,-171 -72.5,-168 -72.5,-165 -72.5,-162 -72.5,-159 -72.5,-156 -72.5,-153 -72.5,-150 -72.5,-150 -73.15,-150 -73.8,-150 -74.45,-150 -75.1,-150 -75.75,-150 -76.4,-150 -77.05,-150 -77.7,-150 -78.35,-150 -79,-153 -79,-156 -79,-159 -79,-162 -79,-165 -79,-168 -79,-171 -79,-174 -79,-177 -79,180 -79,178.2 -79,176.4 -79,174.6 -79,172.8 -79,171 -79,169.2 -79,167.4 -79,165.6 -79,163.8 -79,162 -79,162 -78.35,162 -77.7,162 -77.05,162 -76.4,162 -75.75,162 -75.1,162 -74.45,162 -73.8,162 -73.15,162 -72.5,163.8 -72.5,165.6 -72.5,167.4 -72.5,169.2 -72.5,171 -72.5,172.8 -72.5,174.6 -72.5,176.4 -72.5,178.2 -72.5,-180 -72.5))", "dataset_titles": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020; Ross Island area salinity and temperature records 1956 to 2020", "datasets": [{"dataset_uid": "601458", "doi": "10.15784/601458", "keywords": "Antarctica; CTD; Oceans; Physical Oceanography; Ross Island; Ross Sea; Salinity; Temperature", "people": "Jacobs, Stanley; Giulivi, Claudia F.", "repository": "USAP-DC", "science_program": null, "title": "Ross Island area salinity and temperature records 1956 to 2020", "url": "https://www.usap-dc.org/view/dataset/601458"}, {"dataset_uid": "601611", "doi": "10.15784/601611", "keywords": "Amundsen Sea; Antarctica; Chemistry:Water; CTD; D18O; NBP0001; NBP0702; NBP0901; NBP1901; NBP2002; Oceans; Oxygen Isotope; R/v Nathaniel B. Palmer; Seawater Isotope; Southern Ocean", "people": "Hennig, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020", "url": "https://www.usap-dc.org/view/dataset/601611"}], "date_created": "Fri, 25 Jun 2021 00:00:00 GMT", "description": "This project extended and combined historical and recent ocean data sets to investigate ice-ocean-interactions along the Pacific continental margin of the West Antarctic Ice Sheet. The synthesis focused on the strikingly different environments on and near the cold Ross Sea and warm Amundsen Sea continental shelves, where available measurements reach back to 1911 and 1994, respectively. On the more extensively covered Ross Sea continental shelf, multiple reoccupations of ocean stations and transects since the 1950s were used to extend our knowledge of ocean thermohaline change and variability. The more rugged Amundsen Sea continental shelf contains the earth\u0027s fastest melting ice shelves, which Holland et al (2019) show can be linked to decadal-scale variability in the tropical Pacific, and Jacobs et al. (2021) document as being the primary influence on freshening downstream in the Ross Sea. Recent and potential future rates of sea level rise are the primary broad-scale impacts revealed by the observations of ice and ocean changes in these study areas. More regionally, freshening also influences the properties of slope front and coastal currents, and abyssal water mass formation. The overriding question in such work is whether their contributions to global and regional sea levels will continue to increase ~linearly, perhaps allowing greenhouse gas reductions to head off the worst consequences, or accelerate and contribute to major social and economic upheavals. The compiled ocean station profile data has been derived from measurements made from 16 ships operated by 6 countries, from 5 projects using holes through fast and glacier ice, and from 3 studies using drifting floats. We are grateful to the many individuals who have acquired, processed and provided the data, along with their supporting agencies, and welcome corrections and updates to this archive.\n\n", "east": -150.0, "geometry": "POINT(-174 -75.75)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; AMD; USA/NSF; COMPUTERS; Ross Sea; SHIPS; USAP-DC; SALINITY/DENSITY; OCEAN TEMPERATURE", "locations": "Ross Sea", "north": -72.5, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jacobs, Stanley", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "West Antarctic Ice Shelf- Ocean Interactions ", "uid": "p0010208", "west": 162.0}, {"awards": "1914743 Becker, Thorsten; 1914698 Hansen, Samantha; 1914767 Winberry, Paul; 1914668 Aschwanden, Andy", "bounds_geometry": "POLYGON((90 -65,99 -65,108 -65,117 -65,126 -65,135 -65,144 -65,153 -65,162 -65,171 -65,180 -65,180 -67.5,180 -70,180 -72.5,180 -75,180 -77.5,180 -80,180 -82.5,180 -85,180 -87.5,180 -90,171 -90,162 -90,153 -90,144 -90,135 -90,126 -90,117 -90,108 -90,99 -90,90 -90,90 -87.5,90 -85,90 -82.5,90 -80,90 -77.5,90 -75,90 -72.5,90 -70,90 -67.5,90 -65))", "dataset_titles": "East Antarctic Seismicity from different Automated Event Detection Algorithms; Full Waveform Ambient Noise Tomography for East Antarctica", "datasets": [{"dataset_uid": "601763", "doi": "10.15784/601763", "keywords": "Ambient Noise; Antarctica; East Antarctica; Geoscientificinformation; Seismic Tomography; Seismology", "people": "Hansen, Samantha; Emry, Erica", "repository": "USAP-DC", "science_program": null, "title": "Full Waveform Ambient Noise Tomography for East Antarctica", "url": "https://www.usap-dc.org/view/dataset/601763"}, {"dataset_uid": "601762", "doi": "10.15784/601762", "keywords": "Antarctica; Geoscientificinformation; Machine Learning; Seismic Event Detection; Seismology; Seismometer", "people": "Hansen, Samantha; Ho, Long; Walter, Jacob", "repository": "USAP-DC", "science_program": null, "title": "East Antarctic Seismicity from different Automated Event Detection Algorithms", "url": "https://www.usap-dc.org/view/dataset/601762"}], "date_created": "Fri, 25 Jun 2021 00:00:00 GMT", "description": "Part I: Nontechnical \u003cbr/\u003eEarths warming climate has the potential to drive widespread collapse of glaciers and ice sheets across the planet, driving global sea-level rise. Understanding both the rate and magnitude of such changes is essential for predicting future sea-level and how it will impact infrastructure and property. Collapse of the ice sheets of Antarctica has the potential to raise global sea-level by up to 60 meters. However, not all regions of Antarctica are equally suspectable to collapse. One area with potential for collapse is the Wilkes Subglacial Basin in East Antarctica, a region twice the size of California\u0027s Central Valley. Geologic evidence indicates that the ice-sheet in this region has retreated significantly in response to past global warming events. While the geologic record clearly indicates ice-sheets in this area are vulnerable, the rate and magnitude of any future retreat will be influenced significantly by geology of the region. Constraining the geologic controls on the stability of the ice-sheets of the Wilkes Subglacial Basin remains challenging since the ice-sheet hides the geology beneath kilometers of ice. As a step in understanding the potential for future ice loss in the Wilkes Subglacial Basin this project will conduct geophysical analysis of existing data to better constrain the geology of the region. These results will constrain new models designed to understand the tectonics that control the behavior of the ice-sheets in the region. These new models will highlight the geological properties that exert the most significant control on the future of the ice-sheets of the Wilkes Subglacial Basin. Such insights are critical to guide future efforts aimed at collecting in-situ observations needed to more fully constrain Antarctica\u0027s potential for future sea-level. \u003cbr/\u003e\u003cbr/\u003e Part II: Technical Description \u003cbr/\u003eIn polar environments, inward-sloping marine basins are susceptible to an effect known as the marine ice-sheet instability (MISI): run-away ice stream drainage caused by warm ocean water eroding the ice shelf from below. The magnitude and time-scale of the ice-sheet response strongly depend on the physical conditions along the ice-bed interface, which are, to a first order, controlled by the tectonic evolution of the basin. Topography, sedimentology, geothermal heat flux, and mantle viscosity all play critical roles in ice-sheet stability. However, in most cases, these solid-Earth parameters for regions susceptible to the MISI are largely unknown. One region with potential susceptibility to MISI is the Wilkes Subglacial Basin of East Antarctica. The project will provide an integrated investigation of the Wilkes Subglacial Basin, combining geophysical analyses with both mantle flow and ice-sheet modeling to understand the stability of the ice sheet in this region, and the associated potential sea level rise. The work will be focused on four primary objectives: (1) to develop an improved tectonic model for the region based on existing seismic observations as well as existing geophysical and geological data; (2) to use the new tectonic model and seismic data to estimate the thermal, density, and viscosity structure of the upper mantle and to develop a heat flow map for the WSB; (3) to simulate mantle flow and to assess paleotopography based on our density and viscosity constraints; and (4) to assess ice-sheet behavior by modeling (a) past ice-sheet stability using our paleotopography estimates and (b) future ice-sheet stability using our heat flow and mantle viscosity estimates. Ultimately, the project will generate improved images of the geophysical structure beneath the WSB that will allow us to assess the geodynamic origin for this region and to assess the influence of geologic parameters on past, current, and future ice-sheet behavior. These efforts will then highlight areas and geophysical properties that should be the focus of future geophysical deployments.", "east": 180.0, "geometry": "POINT(135 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "TECTONICS; AMD; Wilkes Subglacial Basin; ICE SHEETS; USA/NSF; Amd/Us; SEISMOLOGICAL STATIONS; SEISMIC SURFACE WAVES; East Antarctica; USAP-DC", "locations": "East Antarctica; Wilkes Subglacial Basin", "north": -65.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Becker, Thorsten; Binder, April; Hansen, Samantha; Aschwanden, Andy; Winberry, Paul", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e SEISMOLOGICAL STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes\r\nSubglacial Basin (RESISSt)", "uid": "p0010204", "west": 90.0}, {"awards": "1850988 Teets, Nicholas", "bounds_geometry": "POLYGON((-64.366767 -62.68104,-63.9917036 -62.68104,-63.6166402 -62.68104,-63.2415768 -62.68104,-62.8665134 -62.68104,-62.49145 -62.68104,-62.1163866 -62.68104,-61.7413232 -62.68104,-61.3662598 -62.68104,-60.9911964 -62.68104,-60.616133 -62.68104,-60.616133 -62.9537037,-60.616133 -63.2263674,-60.616133 -63.4990311,-60.616133 -63.7716948,-60.616133 -64.0443585,-60.616133 -64.3170222,-60.616133 -64.5896859,-60.616133 -64.8623496,-60.616133 -65.1350133,-60.616133 -65.407677,-60.9911964 -65.407677,-61.3662598 -65.407677,-61.7413232 -65.407677,-62.1163866 -65.407677,-62.49145 -65.407677,-62.8665134 -65.407677,-63.2415768 -65.407677,-63.6166402 -65.407677,-63.9917036 -65.407677,-64.366767 -65.407677,-64.366767 -65.1350133,-64.366767 -64.8623496,-64.366767 -64.5896859,-64.366767 -64.3170222,-64.366767 -64.0443585,-64.366767 -63.7716948,-64.366767 -63.4990311,-64.366767 -63.2263674,-64.366767 -62.9537037,-64.366767 -62.68104))", "dataset_titles": "Information on 2023 collection sites for Belgica antarctica; LMG2002 Expedtition Data; Long-term recovery from freezing in Belgica antarctica; Simulated winter warming negatively impacts survival of Antarctica\u0027s only endemic insect", "datasets": [{"dataset_uid": "601694", "doi": null, "keywords": "Antarctica", "people": "Gantz, Josiah D.; Devlin, Jack; Unfried, Laura; Kawarasaki, Yuta; Elnitsky, Michael; Hotaling, Scott; Michel, Andrew; Convey, Peter; Hayward, Scott; Teets, Nicholas; McCabe, Eleanor", "repository": "USAP-DC", "science_program": null, "title": "Simulated winter warming negatively impacts survival of Antarctica\u0027s only endemic insect", "url": "https://www.usap-dc.org/view/dataset/601694"}, {"dataset_uid": "601687", "doi": "10.15784/601687", "keywords": "Antarctica; Antarctic Peninsula; Belgica Antarctica; Biota; Sample Location", "people": "Teets, Nicholas; Peter, Convey; Gantz, Joseph; Devlin, Jack; Michel, Andrew; Kawarasaki, Yuta; Lima, Cleverson; Pavinato, Vitor", "repository": "USAP-DC", "science_program": null, "title": "Information on 2023 collection sites for Belgica antarctica", "url": "https://www.usap-dc.org/view/dataset/601687"}, {"dataset_uid": "200222", "doi": "10.7284/908802", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "LMG2002 Expedtition Data", "url": "https://www.rvdata.us/search/cruise/LMG2002"}, {"dataset_uid": "601698", "doi": "10.15784/601698", "keywords": "Antarctica; Belgica Antarctica; Palmer Station", "people": "Teets, Nicholas; Devlin, Jack; Lecheta, Melise; Lima, Cleverson", "repository": "USAP-DC", "science_program": null, "title": "Long-term recovery from freezing in Belgica antarctica", "url": "https://www.usap-dc.org/view/dataset/601698"}], "date_created": "Fri, 25 Jun 2021 00:00:00 GMT", "description": "The cold, dry terrestrial environments of Antarctica are inhospitable for insects, and only three midge species make Antarctica home. Of these, Belgica antarctica is the only species found exclusively in Antarctica, and it has been a resident of Antarctica since the continent split from South America ~30 million years ago. Thus, this species is an excellent system to model the biological history of Antarctica throughout its repeated glaciation events and shifts in climate. This insect is also a classic example of extreme adaptation, and much previous work has focused on identifying the genetic and physiological mechanisms that allow this species to survive where no other insect is capable. However, it has been difficult to pinpoint the unique evolutionary adaptations that are required to survive in Antarctica due to a lack of information from closely related Antarctic and sub-Antarctic species. This project will compare adaptations, genome sequences, and population characteristics of four midge species that span an environmental gradient from sub-Antarctic to Antarctic habitats. In addition to B. antarctica, these species include two species that are strictly sub-Antarctic and a third that is native to the sub-Antarctic but has invaded parts of Antarctica. The researchers, comprised of scientists from the US, UK, Chile, and France, will sample insects from across their geographic range and measure their ability to tolerate environmental stressors (i.e., cold and desiccation), quantify molecular responses to stress, and compare the makeup of the genome and patterns of genetic diversity. This research will contribute to a greater understanding of adaptation to extremes, to an understanding of biodiversity on the planet and to understanding and predicting changes accompanying environmental change. The project will train two graduate students and two postdoctoral researchers, and a K-12 educator will be a member of the field team and will assist with fieldwork and facilitate outreach with schools in the US. The project includes partnership activities with several STEM education organizations to deliver educational content to K-12 and secondary students. This is a project that is jointly funded by the National Science Foundation\u0027s Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Each Agency funds the proportion of the budget and the investigators associated with its own country. UK participation in this project includes deploying scientists as part of the field team, supporting field and sampling logistics at remote Antarctic sites, and genome sequencing, annotation, and analyses.\r\n\r\nThis project focuses on the key physiological adaptations and molecular processes that allow a select few insect species to survive in Antarctica. The focal species are all wingless with limited dispersal capacity, suggesting there is also significant potential to locally adapt to variable environmental conditions across the range of these species. The central hypothesis is that similar molecular mechanisms drive both population-level adaptation to local environmental conditions and macroevolutionary changes across species living in different environments. The specific aims of the project are to 1) Characterize conserved and species-specific adaptations to extreme environments through comparative physiology and transcriptomics, 2) Compare the genome sequences of these species to identify genetic signatures of extreme adaption, and 3) Investigate patterns of diversification and local adaptation across each species? range using population genomics. The project establishes an international collaboration of researchers from the US, UK, Chile, and France with shared interests and complementary expertise in the biology, genomics, and conservation of Antarctic arthropods. The Broader Impacts of the project include training students and partnering with the Living Arts and Science Center to design and implement educational content for K-12 students.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -60.616133, "geometry": "POINT(-62.49145 -64.0443585)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; Livingston Island; Antarctica; USAP-DC; AMD; R/V LMG; USA/NSF; ARTHROPODS; Amd/Us; Anvers Island", "locations": "Antarctica; Antarctic Peninsula; Anvers Island; Livingston Island", "north": -62.68104, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Teets, Nicholas; Michel, Andrew", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -65.407677, "title": "NSFGEO-NERC: Mechanisms of Adaptation to Terrestrial Antarctica through Comparative Physiology and Genomics of Antarctic and sub-Antarctic Insects", "uid": "p0010203", "west": -64.366767}, {"awards": "1906015 Kelley, Joanna", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Data, Code, and Results for the Zoarcoidei Phylogeny (Hotaling et al.)", "datasets": [{"dataset_uid": "200221", "doi": "10.5281/zenodo.4306092).", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Data, Code, and Results for the Zoarcoidei Phylogeny (Hotaling et al.)", "url": "https://doi.org/10.5281/zenodo.4306092"}], "date_created": "Fri, 25 Jun 2021 00:00:00 GMT", "description": "Fish that reside in the harsh, subfreezing waters of the Antarctic and Arctic provide fascinating examples of adaptation to extreme environments. Species at both poles have independently evolved ways to deal with constant cold temperature, including the evolution of antifreeze proteins. Under freezing conditions, these compounds attach to ice crystals and prevent their growth. This lowers the tissue freezing point and reduces the chance the animal will be injured or killed. While it might seem that the need for unique adaptations to survive in polar waters would reduce species diversity in these habitats, recent evidence showed higher speciation rates in fishes from polar environments as compared to those found in warmer waters. This is despite the fact cold temperatures slow cellular processes, which had been expected to lower rates of molecular evolution in these species. To determine how rates of speciation and molecular evolution are linked in marine fishes, this project will compare the genomes of multiple polar and non-polar fishes. By doing so, it will (1) clarify how rates of evolution vary in polar environments, (2) identify general trends that shape the adaptive trajectories of polar fishes, and (3) determine how functional differences shape the evolution of novel compounds such as the antifreeze proteins some polar fishes rely upon to survive. In addition to training a new generation of scientists, the project will develop curriculum and outreach activities for elementary and undergraduate science courses. Materials will be delivered in classrooms across the western United States, with a focus on rural schools as part of a network for promoting evolutionary education in rural communities.\r\n\r\nTo better understand the biology of polar fishes and the evolution of antifreeze proteins (AFPs), this research will compare the evolutionary histories of cold-adapted organisms to those of related non-polar species from both a genotypic and phenotypic context. In doing so, this research will test whether evolutionary rates are slowed in polar environments, perhaps due to constraints on cellular processes. It will also evaluate the effects of positive selection and the relaxation of selection on genes and pathways, both of which appear to be key adaptive strategies involved in the adaptation to polar environments. To address specific mechanisms by which extreme adaptation occurs, researchers will determine how global gradients of temperature and dissolved oxygen shape genome variation and influence adaptive trajectories among multiple species of eelpouts (family Zoarcidae). An in-vitro experimental approach will then be used to test functional hypotheses about the role of copy number variation in AFP evolution, and how and why multiple antifreeze protein isoforms have evolved. By comparing the genomes of multiple polar and non-polar fishes, the project will clarify how rates of evolution vary in polar environments, identify general trends that shape the adaptive trajectories of cold-adapted marine fishes, and determine how functional differences shape the evolution of novel proteins. This project addresses the strategic programmatic aim to provide a better understanding of the genetic underpinnings of organismal adaptations to their current environment and ways in which polar fishes may respond to changing conditions over different evolutionary time scales. The project is jointly funded by the Antarctic Organisms and Ecosystems Program in the Office of Polar Programs of the Geosciences Directorate, and the Molecular Biophysics Program of the Division of Molecular and Cellular Biosciences in the Biological Sciences Directorate.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; FISH; MARINE ECOSYSTEMS; LABORATORY; AMD; USAP-DC; Amd/Us; USA/NSF", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kelley, Joanna", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "Zenodo", "repositories": "Zenodo", "science_programs": null, "south": -90.0, "title": "Genome Evolution in Polar Fishes", "uid": "p0010200", "west": -180.0}, {"awards": "1640481 Rotella, Jay", "bounds_geometry": "POLYGON((162 -75,162.8 -75,163.6 -75,164.4 -75,165.2 -75,166 -75,166.8 -75,167.6 -75,168.4 -75,169.2 -75,170 -75,170 -75.38,170 -75.76,170 -76.14,170 -76.52,170 -76.9,170 -77.28,170 -77.66,170 -78.03999999999999,170 -78.42,170 -78.8,169.2 -78.8,168.4 -78.8,167.6 -78.8,166.8 -78.8,166 -78.8,165.2 -78.8,164.4 -78.8,163.6 -78.8,162.8 -78.8,162 -78.8,162 -78.42,162 -78.03999999999999,162 -77.66,162 -77.28,162 -76.9,162 -76.52,162 -76.14,162 -75.76,162 -75.38,162 -75))", "dataset_titles": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2017 Antarctic field season; Demographic data for Weddell Seal colonies in Erebus Bay through the 2023 Antarctic field season", "datasets": [{"dataset_uid": "200300", "doi": " https://doi.org/10.15784/601125 ", "keywords": null, "people": null, "repository": "USAP-DC", "science_program": null, "title": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2017 Antarctic field season", "url": "https://www.usap-dc.org/view/dataset/601125"}, {"dataset_uid": "601837", "doi": null, "keywords": "AMD; Amd/Us; Antarctica; Cryosphere; McMurdo Sound; Population Dynamics; USA/NSF; USAP-DC; Weddell Seal", "people": "Rotella, Jay", "repository": "USAP-DC", "science_program": null, "title": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2023 Antarctic field season", "url": "https://www.usap-dc.org/view/dataset/601837"}], "date_created": "Thu, 24 Jun 2021 00:00:00 GMT", "description": "The Erebus Bay population of Weddell seals in the Ross Sea of Antarctica is the most southerly breeding population of mammal in the world, closely associated with persistent shore-fast ice, and one that has been intensively studied since 1969. The resulting long-term database, which includes data for over 25,000 marked individuals, contains detailed population information that provides an excellent opportunity to study linkages between environmental conditions and demographic processes in the Antarctic. The study population is of special interest as the Ross Sea is one of the most productive areas of the Southern Ocean and one of the most pristine marine environments on the planet. The study provides long-term demographic data for individual seals", "east": 170.0, "geometry": "POINT(166 -76.9)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; ANIMAL ECOLOGY AND BEHAVIOR; Amd/Us; FIELD INVESTIGATION; Ross Sea; USA/NSF; USAP-DC", "locations": "Ross Sea", "north": -75.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rotella, Jay; Garrott, Robert", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.8, "title": "The consequences of maternal effects and environmental conditions on offspring success in an Antarctic predator", "uid": "p0010198", "west": 162.0}, {"awards": "1643494 Saal, Alberto", "bounds_geometry": "POLYGON((-68.074 -57.345,-66.6033 -57.345,-65.1326 -57.345,-63.6619 -57.345,-62.1912 -57.345,-60.7205 -57.345,-59.2498 -57.345,-57.7791 -57.345,-56.3084 -57.345,-54.8377 -57.345,-53.367 -57.345,-53.367 -58.12517,-53.367 -58.90534,-53.367 -59.68551,-53.367 -60.46568,-53.367 -61.24585,-53.367 -62.02602,-53.367 -62.80619,-53.367 -63.58636,-53.367 -64.36653,-53.367 -65.1467,-54.8377 -65.1467,-56.3084 -65.1467,-57.7791 -65.1467,-59.2498 -65.1467,-60.7205 -65.1467,-62.1912 -65.1467,-63.6619 -65.1467,-65.1326 -65.1467,-66.6033 -65.1467,-68.074 -65.1467,-68.074 -64.36653,-68.074 -63.58636,-68.074 -62.80619,-68.074 -62.02602,-68.074 -61.24585,-68.074 -60.46568,-68.074 -59.68551,-68.074 -58.90534,-68.074 -58.12517,-68.074 -57.345))", "dataset_titles": "Major, trace elements contents and radiogenic isotopes of erupted lavas Antarctic Peninsula and Phoenix Ridge", "datasets": [{"dataset_uid": "601519", "doi": "10.15784/601519", "keywords": "Antarctica; Antarctic Peninsula; Chemical Composition; Chemistry:rock; Chemistry:Rock; Geochemistry; Isotope Data; Trace Elements", "people": "Saal, Alberto", "repository": "USAP-DC", "science_program": null, "title": "Major, trace elements contents and radiogenic isotopes of erupted lavas Antarctic Peninsula and Phoenix Ridge", "url": "https://www.usap-dc.org/view/dataset/601519"}], "date_created": "Tue, 22 Jun 2021 00:00:00 GMT", "description": "The focus of our research is to examine the regional geochemical variations of well-characterized Pliocene-recent basalt samples along a transect from the Phoenix-Antarctic ridge to James Ross Island (through the South Shetland Islands, Bransfield Strait and the Antarctic Peninsula). The goal is to understand 1) the processes responsible for the generation of chemically diverse basalts in close spatial and temporal proximity within the Antarctic Peninsula and 2) the nature (lithology, composition and temperature) of the heterogeneous mantle source beneath the region.", "east": -53.367, "geometry": "POINT(-60.7205 -61.24585)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; USA/NSF; USAP-DC; TRACE ELEMENTS; MAJOR ELEMENTS; Amd/Us; LABORATORY; ROCKS/MINERALS/CRYSTALS; Magmatic Volatiles; AMD", "locations": "Antarctic Peninsula", "north": -57.345, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Saal, Alberto", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.1467, "title": "Magmatic Volatiles, Unraveling the Reservoirs and Processes of the Volcanism in the Antarctic Peninsula", "uid": "p0010196", "west": -68.074}, {"awards": "1643119 Zabotin, Nikolay", "bounds_geometry": "POLYGON((-180 -73,-177 -73,-174 -73,-171 -73,-168 -73,-165 -73,-162 -73,-159 -73,-156 -73,-153 -73,-150 -73,-150 -74.2,-150 -75.4,-150 -76.6,-150 -77.8,-150 -79,-150 -80.2,-150 -81.4,-150 -82.6,-150 -83.8,-150 -85,-153 -85,-156 -85,-159 -85,-162 -85,-165 -85,-168 -85,-171 -85,-174 -85,-177 -85,180 -85,178 -85,176 -85,174 -85,172 -85,170 -85,168 -85,166 -85,164 -85,162 -85,160 -85,160 -83.8,160 -82.6,160 -81.4,160 -80.2,160 -79,160 -77.8,160 -76.6,160 -75.4,160 -74.2,160 -73,162 -73,164 -73,166 -73,168 -73,170 -73,172 -73,174 -73,176 -73,178 -73,-180 -73))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 22 Jun 2021 00:00:00 GMT", "description": "Recent theoretical and experimental work indicates that in a wide range of altitudes and for periods from a few minutes to several hours, a significant part of the wave activity observed in the thermosphere is due to acoustic gravity waves radiated by infragravity waves in the ocean. It is proposed to study this impressive connection between geospheres in Antarctica, at the location where close proximity of the Ross Ice Shelf makes it very special. Infragravity waves are able to excite the fundamental mode and low-order oscillations in the Ross Ice Shelf at its resonance frequencies, with the latter creating standing wave structures throughout the atmosphere. It is likely that this effect was recently detected using lidar observations at McMurdo. This project will study implications of this phenomenon, as well as more general aspects of wave activity in Antarctic geospheres, using data from a unique combination of recently installed instruments: the Dynasonde at Korean Jang Bogo station, the NSF-sponsored network of seismographs and microbarometers on the Ross Ice Shelf, and the IMS-affiliated infrasound station near McMurdo.\r\n\r\nThe goal of this research is to study atmospheric waves in the thermosphere in Antarctica and to investigate the roles that the Ross Ice Shelf and the Southern Ocean play in generation of the atmospheric waves. Anticipated results are of interest also for general aeronomy and for glaciology. This project will verify the hypothesis that the persistent atmospheric waves in mesosphere and lower thermosphere, which are observed with a lidar instrument at McMurdo, are related to the low-frequency vibration resonances of the Ross Ice Shelf excited by infragravity waves in the ocean. An accurate characterization will be achieved for low-frequency oscillations of the Ross Ice Shelf and the quality factors of its resonances will be assessed. Investigation of a consistency between observed and predicted vertical distributions of the wave intensity is expected to provide insights into where the horizontal momentum carried by AGWs is transferred to the mean motion, i.e., to the large-scale dynamics of the Antarctic thermosphere. A determination of whether accurate measurements of the acoustic resonant frequencies and their variations can provide useful constraints on the neutral temperature profile in the atmosphere will be done. Extensive use of Jang Bogo Dynasonde data in all mentioned tasks will allow further developing Dynasonde techniques.", "east": -150.0, "geometry": "POINT(-175 -79)", "instruments": null, "is_usap_dc": true, "keywords": "Ronne Ice Shelf; USA/NSF; Amd/Us; AMD; SEA ICE MOTION; FIELD INVESTIGATION; USAP-DC", "locations": "Ronne Ice Shelf", "north": -73.0, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Godin, Oleg; Zabotin, Nikolay", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": -85.0, "title": "Resonance Properties of the Ross Ice Shelf, Antarctica, as a Factor in Regional Wave Interaction between Ocean and Atmosphere", "uid": "p0010195", "west": 160.0}, {"awards": "1750888 Aronson, Richard; 1750903 Ingels, Jeroen; 1750630 Smith, Craig", "bounds_geometry": "POLYGON((-64 -66,-63.3 -66,-62.6 -66,-61.9 -66,-61.2 -66,-60.5 -66,-59.8 -66,-59.1 -66,-58.4 -66,-57.7 -66,-57 -66,-57 -66.3,-57 -66.6,-57 -66.9,-57 -67.2,-57 -67.5,-57 -67.8,-57 -68.1,-57 -68.4,-57 -68.7,-57 -69,-57.7 -69,-58.4 -69,-59.1 -69,-59.8 -69,-60.5 -69,-61.2 -69,-61.9 -69,-62.6 -69,-63.3 -69,-64 -69,-64 -68.7,-64 -68.4,-64 -68.1,-64 -67.8,-64 -67.5,-64 -67.2,-64 -66.9,-64 -66.6,-64 -66.3,-64 -66))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 21 Jun 2021 00:00:00 GMT", "description": "Worldwide publicity surrounding the calving of an iceberg the size of Delaware in July 2017 from the Larsen C Ice Shelf on the eastern side of the Antarctic Peninsula presents a unique and time-sensitive opportunity for research and education on polar ecosystems in a changing climate. The goal of this project was to convene a workshop, drawing from the large fund of intellectual capital in the US and international Antarctic research communities. The two-day workshop was designed to bring scientists with expertise in Antarctic biological, ecological, and ecosystem sciences to Florida State University to share knowledge, identify important research knowledge gaps, and outline strategic plans for research. Major outcomes from the project were as follows. The international workshop to share and review knowledge concerning the response of Antarctic ecosystems to ice-shelf collapse was held at the Florida State University Coastal and Marine Laboratory (FSUCML) on 18-19 November 2017. Thirty-eight U.S. and international scientists attended the workshop, providing expertise in biological, ecological, geological, biogeographical, and glaciological sciences. Twenty-six additional scientists were either not able to attend or were declined because of having reached maximum capacity of the venue or for not responding to our invitation before the registration deadline. The latest results of ice-shelf research were presented, providing an overview of the current scientific knowledge and understanding of the biological, ecological, geological and cryospheric processes associated with ice-shelf collapse and its ecosystem-level consequences. In addition, several presentations focused on future plans to investigate the impacts of the recent Larsen C collapse. The following presentations were given at the meeting: 1) Cryospheric dynamics and ice-shelf collapse \u2013 past and future (M. Truffer, University of Alaska, Fairbanks) 2) The geological history and geological impacts of ice-shelf collapse on the Antarctic Peninsula (Scottt Ishman, Amy Leventer) 3) Pelagic ecosystem responses to ice-shelf collapse (Mattias Cape, Amy Leventer) 4) Benthic ecosystem response to ice-shelf collapse (Craig Smith, Pavica Sr\u0161en, Ann Vanreusel) 5) Larsen C and biotic homogenization of the benthos (Richard Aronson, James McClintock, Kathryn Smith, Brittany Steffel) 6) British Antarctic Survey: plans for Larsen C investigations early 2018 and in the future (Huw Griffiths) 7) Feedback on the workshop \u201cClimate change impacts on marine ecosystems: implications for management of living resources and conservation\u201d held 19-22 September 2017, Cambridge, UK (Alex Rogers) 8) Past research activities and plans for Larsen field work by the Alfred Wegener Institute, Germany (Charlotte Havermans, Dieter Piepenburg. One of the salient points emerging from the presentations and ensuing discussions was that, given our poor abilities to predict ecological outcomes of ice-shelf collapses, major cross-disciplinary efforts are needed on a variety of spatial and temporal scales to achieve a broader, predictive understanding of ecosystem consequences of climatic warming and ice-shelf failure. As part of the workshop, the FSUCML Polar Academy Team\u2014Dr. Emily Dolan, Dr. Heidi Geisz, Barbara Shoplock, and Dr. Jeroen Ingels\u2014initiated AntICE: \"Antarctic Influences of Climate Change on Ecosystems\" (AntICE). They reached out to various groups of school children in the local area (and continue to do so). The AntICE Team have been interacting with these children at Wakulla High School and Wakulla Elementary in Crawfordville; children from the Cornerstone Learning Community, Maclay Middle School, Gilchrist Elementary, and the School of Arts and Sciences in Tallahassee; and the Tallahassee-area homeschooling community to educate them about Antarctic ecosystems and ongoing climate change. The underlying idea was to make the children aware of climatic changes in the Antarctic and their effect on ecosystems so they, in turn, can spread this knowledge to their communities, family and friends \u2013 acting as \u2018Polar Ambassadors\u2019. We collaborated with the Polar-ICE project, an NSF-funded educational project that established the Polar Literacy Initiative. This program developed the Polar Literacy Principles, which outline essential concepts to improve public understanding of Antarctic and Arctic ecosystems. In the Polar Academy work, we used the Polar Literacy principles, the Polar Academy Team\u2019s own Antarctic scientific efforts, and the experience of the FSU outreach and education program to engage with the children. We focused on the importance of Antarctic organisms and ecosystems, the uniqueness of its biota and the significance of its food webs, as well as how all these are changing and will change further with climate change. Using general presentations, case studies, scientific methodology, individual experiences, interactive discussions and Q\u0026A sessions, the children were guided through the many issues Antarctic ecosystems are facing. Over 300 \u0027\u0027Polar ambassadors\u0027\u0027 attended the interactive lectures and afterwards took their creativity to high latitudes by creating welcome letters, displays, dioramas, sculptures, videos and online media to present at the scientific workshop. Over 50 projects were created by the children (Please see supporting files for images). We were also joined by a photographer, Ryan David Reines, to document the event. More information, media and links to online outreach products are available at https://marinelab.fsu.edu/labs/ingels/outreach/polar-academy/\n\nFurther concrete products of the workshop: 1) a position-paper focusing on ideas, hypotheses and priorities for investigating the ecological impacts of ice-shelf collapse along the Antarctic Peninsula (Ingels et al., 2018; \u201cThe scientific response to Antarctic ice-shelf loss; Nature Climate Change 8, 848-851), and 2) a publication reviewing what is known and unknown about ecological responses to ice-shelf melt and collapse, outlining expected ecological outcomes of ice-shelf disintegration along the Antarctic Peninsula (Ingels et al., 2020; \u201cAntarctic ecosystem responses following ice\u2010shelf collapse and iceberg calving: Science review and future research\u201d, WIREs Climate Change, e682). The second publication was covered in the The Scientist and by a press-release in Germany, see https://www.altmetric.com/details/91826381. Other products included a poster presentation at the MEASO2018 conference in Hobart, Australia in 2018, and the above-mentioned visits to schools and institutes to talk about the research in invited seminars. We also conducted and active online outreach campaign, with dissemination of our work in various news outlets, blogs, and social media (e.g. reaching \u003e750k total followers on twitter with the publications alone).\u0027", "east": -57.0, "geometry": "POINT(-60.5 -67.5)", "instruments": null, "is_usap_dc": true, "keywords": "MARINE ECOSYSTEMS; USAP-DC; LABORATORY; AMD; Weddell Sea; GLACIERS/ICE SHEETS; ECOLOGICAL DYNAMICS; USA/NSF; SEA ICE; Amd/Us; Antarctica", "locations": "Antarctica; Weddell Sea", "north": -66.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ingels, Jeroen; Aronson, Richard; Smith, Craig", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -69.0, "title": "Collaborative Research: RAPID/Workshop - Antarctic Ecosystem Research following Ice Shelf Collapse and Iceberg Calving Events", "uid": "p0010189", "west": -64.0}, {"awards": "2042495 Blackburn, Terrence; 2045611 Rasbury, Emma", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Subglacial precipitates record Antarctic ice sheet response to Southern Ocean warming ; U-series Geochronology, Isotope, and Elemental Geochemistry of a Subglacial Precipitate that Formed Across Termination III; U-Th isotopes and major elements in sediments from Taylor Valley, Antarctica", "datasets": [{"dataset_uid": "601806", "doi": "10.15784/601806", "keywords": "Antarctica; Cryosphere; Erosion; Isotope Data; Major Elements; Soil; Taylor Glacier; Taylor Valley", "people": "Piccione, Gavin; Tulaczyk, Slawek; Edwards, Graham; Blackburn, Terrence", "repository": "USAP-DC", "science_program": null, "title": "U-Th isotopes and major elements in sediments from Taylor Valley, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601806"}, {"dataset_uid": "601781", "doi": "10.15784/601781", "keywords": "Antarctica; Carbon; Carbon Isotopes; Cryosphere; East Antarctica; Elephant Moraine; Geochronology; Isotope Data; Opal; Oxygen Isotope; Sr; Subglacial; U", "people": "Piccione, Gavin", "repository": "USAP-DC", "science_program": null, "title": "U-series Geochronology, Isotope, and Elemental Geochemistry of a Subglacial Precipitate that Formed Across Termination III", "url": "https://www.usap-dc.org/view/dataset/601781"}, {"dataset_uid": "601800", "doi": "10.15784/601800", "keywords": "Antarctica; Cryosphere", "people": "Gagliardi, Jessica", "repository": "USAP-DC", "science_program": null, "title": "Subglacial precipitates record Antarctic ice sheet response to Southern Ocean warming ", "url": "https://www.usap-dc.org/view/dataset/601800"}], "date_created": "Fri, 18 Jun 2021 00:00:00 GMT", "description": "Efforts to improve sea level forecasting on a warming planet have focused on determining the temperature, sea level and extent of polar ice sheets during Earth\u2019s past warm periods. Large uncertainties, however, in reconstructions of past and future sea levels, result from the poorly constrained climate sensitivity of the Antarctic Ice sheet (AIS). This research project aims to develop the use of subglacial precipitates as an archive the Antarctic ice sheet (AIS) past response to climate change. The subglacial precipitates from East Antarctica form in water bodies beneath Antarctic ice and in doing so provide an entirely new and unique measure of how the AIS responds to climate change. In preliminary examination of these precipitates, we identified multiple samples consisting of cyclic opal and calcite that spans hundreds of thousands of years in duration. Our preliminary geochemical characterization of these samples indicates that the observed mineralogic changes result from a cyclic change in subglacial water compositions between isotopically and chemically distinct waters. Opal-forming waters are reduced (Ce* \u003c1 and high Fe/Mn) and exhibit elevated 234U/238U compositions similar to the saline groundwater brines found at the periphery of the AIS. Calcite-forming waters, are rather, oxidized and exhibit \u03b418O compositions consistent with derivation from the depleted polar plateau (\u003c -50 \u2030). 234U-230Th dates permit construction of a robust timeseries describing these mineralogic and compositional changes through time. Comparisons of these time series with other Antarctic climate records (e.g., ice core records) reveal that calcite forming events align with millennial scale changes in local temperature or \u201cAntarctic isotopic maximums\u201d, which represent Southern Hemisphere warm periods during low Atlantic Meridional overturning circulation. Ultimately, this project seeks to develop a comprehensive model as to how changes in the thermohaline cycle induce a glaciologic response which in turn induces a change in the composition of subglacial waters and the mineralogic phase recorded within the precipitate archive. ", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; FIELD INVESTIGATION; AMD; USA/NSF; Amd/Us; USAP-DC; East Antarctica", "locations": "East Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Blackburn, Terrence; Tulaczyk, Slawek; Hain, Mathis; Rasbury, Troy", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates", "uid": "p0010192", "west": -180.0}, {"awards": "1443342 Licht, Kathy; 1443556 Thomson, Stuart", "bounds_geometry": null, "dataset_titles": "Apatite (U-Th)/He and TREE Data Central Transantarctic Mountains", "datasets": [{"dataset_uid": "601462", "doi": "10.15784/601462", "keywords": "Antarctica; Beardmore Glacier; Erosion; Landscape Evolution; Shackleton Glacier; Transantarctic Mountains; (U-Th)/He", "people": "Licht, Kathy; Hemming, Sidney R.; Reiners, Peter; He, John; Thomson, Stuart", "repository": "USAP-DC", "science_program": null, "title": "Apatite (U-Th)/He and TREE Data Central Transantarctic Mountains", "url": "https://www.usap-dc.org/view/dataset/601462"}], "date_created": "Wed, 09 Jun 2021 00:00:00 GMT", "description": "Antarctica is almost entirely covered by ice, in places over two miles thick. This ice hides a landscape that is less well known than the surface of Mars and represents one of Earth\u0027s last unexplored frontiers. Ice-penetrating radar images provide a remote glimpse of this landscape including ice-buried mountains larger than the European Alps and huge fjords twice as deep as the Grand Canyon. The goal of this project is to collect sediment samples derived from these landscapes to determine when and under what conditions these features formed. Specifically, the project seeks to understand the landscape in the context of the history and dynamics of the overlying ice sheet and past mountain-building episodes. This project accomplishes this goal by analyzing sand collected during previous sea-floor drilling expeditions off the coast of Antarctica. This sand was supplied from the continent interior by ancient rivers when it was ice-free over 34 million year ago, and later by glaciers. The project will also study bedrock samples from rare ice-free parts of the Transantarctic Mountains. The primary activity is to apply multiple advanced dating techniques to single mineral grains contained within this sand and rock. Different methods and minerals yield different dates that provide insight into how Antarctica?s landscape has eroded over the many tens of millions of years during which sand was deposited offshore. The dating techniques that are being developed and enhanced for this study have broad application in many branches of geoscience research and industry. The project makes cost-effective use of pre-existing sample collections housed at NSF facilities including the US Polar Rock Repository, the Gulf Coast Core Repository, and the Antarctic Marine Geology Research Facility. The project will contribute to the STEM training of two graduate and two undergraduate students, and includes collaboration among four US universities as well as international collaboration between the US and France. The project also supports outreach in the form of a two-week open workshop giving ten students the opportunity to visit the University of Arizona to conduct STEM-based analytical work and training on Antarctic-based projects. Results from both the project and workshop will be disseminated through presentations at professional meetings, peer-reviewed publications, and through public outreach and media.\r\n\r\n\r\nThe main objective of this project is to reconstruct a chronology of East Antarctic subglacial landscape evolution to understand the tectonic and climatic forcing behind landscape modification, and how it has influenced past ice sheet inception and dynamics. Our approach focuses on acquiring a record of the cooling and erosion history contained in East Antarctic-derived detrital mineral grains and clasts in offshore sediments deposited both before and after the onset of Antarctic glaciation. Samples will be taken from existing drill core and marine sediment core material from offshore Wilkes Land (100\u00b0E-160\u00b0E) and the Ross Sea. Multiple geo- and thermo-chronometers will be employed to reconstruct source region cooling history including U-Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar. This offshore record will be augmented and tested by applying the same methods to onshore bedrock samples in the Transantarctic Mountains obtained from the US Polar Rock Repository and through fieldwork. The onshore work will additionally address the debated incision history of the large glacial troughs that cut the range, now occupied by glaciers draining the East Antarctic Ice Sheet. This includes collection of samples from several age-elevation transects, apatite 4He/3He thermochronometry, and Pecube thermo-kinematic modeling. Acquiring an extensive geo- and thermo-chronologic database will also provide valuable new information on the poorly known ice-hidden geology and tectonics of subglacial East Antarctica that has implications for improving supercontinent reconstructions and understanding continental break-up.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "LABORATORY; LANDSCAPE; AGE DETERMINATIONS; FIELD INVESTIGATION; GLACIAL PROCESSES; Transantarctic Mountains; USA/NSF; Thermochronology; Amd/Us; USAP-DC; TRACE ELEMENTS; Provenance Analysis; AMD; LANDFORMS; GLACIAL LANDFORMS", "locations": "Transantarctic Mountains", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Thomson, Stuart; Reiners, Peter; Licht, Kathy", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: East Antarctic Glacial Landscape Evolution (EAGLE): A Study using Combined Thermochronology, Geochronology and Provenance Analysis", "uid": "p0010188", "west": null}, {"awards": "1745130 Moran, Amy", "bounds_geometry": "POLYGON((163 -76,163.3 -76,163.6 -76,163.9 -76,164.2 -76,164.5 -76,164.8 -76,165.1 -76,165.4 -76,165.7 -76,166 -76,166 -76.2,166 -76.4,166 -76.6,166 -76.8,166 -77,166 -77.2,166 -77.4,166 -77.6,166 -77.8,166 -78,165.7 -78,165.4 -78,165.1 -78,164.8 -78,164.5 -78,164.2 -78,163.9 -78,163.6 -78,163.3 -78,163 -78,163 -77.8,163 -77.6,163 -77.4,163 -77.2,163 -77,163 -76.8,163 -76.6,163 -76.4,163 -76.2,163 -76))", "dataset_titles": "Egg diameters of Colossendeis megalonyx; Video of Colossendeis megalonyx behavior around egg mass", "datasets": [{"dataset_uid": "601717", "doi": "10.15784/601717", "keywords": "Antarctica; McMurdo", "people": "Moran, Amy", "repository": "USAP-DC", "science_program": null, "title": "Egg diameters of Colossendeis megalonyx", "url": "https://www.usap-dc.org/view/dataset/601717"}, {"dataset_uid": "601716", "doi": "10.15784/601716", "keywords": "Antarctica; McMurdo; Pycnogonida; Sea Spider", "people": "Moran, Amy; Lobert, Graham", "repository": "USAP-DC", "science_program": null, "title": "Video of Colossendeis megalonyx behavior around egg mass", "url": "https://www.usap-dc.org/view/dataset/601716"}], "date_created": "Wed, 09 Jun 2021 00:00:00 GMT", "description": "Antarctic marine ectotherms exhibit universally slow growth, low metabolic rates, and extended development, yet many of their rate processes related to physiology and metabolism are highly thermally sensitive. This suggests that small changes in temperature may result in dramatic changes to energy metabolism, growth, and the rate and duration of development. This project will measure the effects of temperature on metabolism, developmental rate, and the energetic cost of development of four common and ecologically important species of benthic Antarctic marine invertebrates. These effects will be measured over the functional ranges of the organisms and in the context of environmentally relevant seasonal shifts in temperature around McMurdo Sound. Recent data show that seasonal warming of ~1\u00b0C near McMurdo Station is accompanied by long-lasting hyperoxic events that impact the benthos in the nearshore boundary layer. This research will provide a more comprehensive understanding of both annual variation in environmental oxygen and temperature across the Sound, and whether this variation drives changes in developmental rate and energetics that are consistent with physiological acclimatization. These data will provide key information about potential impacts of warming Antarctic ectotherms. In addition, this project will support undergraduate and graduate research and partner with large-enrollment undergraduate courses and REU programs at an ANNH and AANAPISI Title III minority-serving institution. \r\nWe have completed one of our two scheduled field and data-collecting seasons, but our research was put on hold by COVID and by equipment and sea ice conditions at McMurdo. We have established baseline information on energy utilization by embryos of several species under ambient conditions and early data suggest that metabolism is highly affected by temperature in the range of -2.0 C to 1 C, and less so thereafter.", "east": 166.0, "geometry": "POINT(164.5 -77)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; Amd/Us; McMurdo Sound; AMD; BENTHIC; USA/NSF; FIELD INVESTIGATION", "locations": "McMurdo Sound", "north": -76.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Moran, Amy", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Thermal Sensitivity of Antarctic Embryos and Larvae: Effects of Temperature on Metabolism, Developmental Rate, and the Metabolic Cost of Development ", "uid": "p0010187", "west": 163.0}, {"awards": "1743310 Kingslake, Jonathan", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Vulnerability of Antarctica\u2019s ice shelves to meltwater-driven fracture", "datasets": [{"dataset_uid": "601395", "doi": "10.15784/601395", "keywords": "Antarctica; Computer Model; Fractures; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Meltwater; Model Data", "people": "Lai, Ching-Yao", "repository": "USAP-DC", "science_program": null, "title": "Vulnerability of Antarctica\u2019s ice shelves to meltwater-driven fracture", "url": "https://www.usap-dc.org/view/dataset/601395"}], "date_created": "Wed, 02 Jun 2021 00:00:00 GMT", "description": "Ice shelves slow the movement of the grounded ice sheets that feed them. This reduces the rate at which ice sheets loose mass to the oceans and contribute to sea-level rise. But ice shelves can be susceptible to collapse, particularly when surface meltwater accumulates in vulnerable areas. Meltwater lakes can create and enlarge fractures within the ice shelves, thereby triggering or hastening ice-shelf collapse. The drainage of water across the surface of Antarctica and where it accumulates has received little attention. This drainage was assumed to be insignificant, but recent work shows that meltwater can drain for tens of kilometers across ice-shelf surfaces and access areas that would otherwise not accumulate meltwater. Surface meltwater drainage could play a major role in the future stability of ice sheets. This drainage is the focus of this project.\r\n\r\nThe team will develop and test physics-based mathematical models of water flow and ice-shelf fracture, closely informed by remote sensing observations, to examine (1) how do surface drainage systems respond to inter-annual changes in surface melting, (2) how this drainage is influenced by ice dynamics and (3) whether enlarged drainage systems could deliver meltwater to areas of ice shelves that are vulnerable to water-driven collapse. The project will examine these issues by (1) conducting a remote sensing survey of the structure and temporal evolution of meltwater systems around Antarctica, (2) developing and analyzing mathematical models of water flow across ice shelves, and (3) developing and testing simple models of ice-shelf fracture. An outreach activity will make use of the emerging technology of Augmented Reality to visualize the dynamics of ice sheets in three dimensions to excite the public about glaciology at outreach events around New York City. This approach will be made publicly available for wider use as Augmented Reality continues to grow in popularity.\r\n\r\nThree aspects of the project will produce data and code that will be archived in USAP-DC:\r\n1. Mapped ice-shelf drainage system characteristics.\r\n2. Computed continent-wide fields of ice-shelf vulnerability to hydrofracture.\r\n3. An open source augmented reality ice sheet app.\r\n\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; AMD; USAP-DC; Antarctica; ICE SHEETS; Amd/Us; Ice Shelf; COMPUTERS; Surface Meltwater", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Kingslake, Jonathan", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Satellite observations and modelling of surface meltwater flow and its impact on ice shelves", "uid": "p0010184", "west": -180.0}, {"awards": "1543344 Soreghan, Gerilyn", "bounds_geometry": null, "dataset_titles": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "datasets": [{"dataset_uid": "601599", "doi": "10.15784/601599", "keywords": "Antarctica; Anza Borrego; Iceland; McMurdo Dry Valleys; Norway; Peru; Puerto Rico; Taylor Valley; Washington; Wright Valley", "people": "Demirel-Floyd, Cansu", "repository": "USAP-DC", "science_program": null, "title": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "url": "https://www.usap-dc.org/view/dataset/601599"}], "date_created": "Tue, 18 May 2021 00:00:00 GMT", "description": "As glaciers creep across the landscape, they can act as earthmovers, plucking up rocks and grinding them into fine sediments. Glaciers have moved across the Antarctic landscape over thousands to millions of years, leaving these ground-up sediments in their wake. This study builds on pilot discoveries by the investigators that revealed remarkably large and variable measurements of surface area in glacially-derived fine-grained sediments found in the McMurdo Dry Valleys (MDV), one of the few landscapes on the Antarctic continent not currently covered by ice. Surface area is key to chemical weathering, the process by which rock is converted to soils as ions are carried away in streams and groundwater. These chemical weathering processes are also one of the primary means by which the Earth system naturally removes carbon dioxide from the atmosphere. Hence, high surface areas observed in sediments implies high \"weatherability\" which in turn translates to more potential carbon dioxide removed from the atmosphere. Therefore, chemical weathering in high surface area glacial sediments may have significant impacts on Earth\u0027s carbon cycle. The researchers will measure the chemical and physical properties of sediments previously collected from the Dry Valleys to understand what factors lead to production of sediment with high-surface area and potential \"weather ability\" and investigate how sediment produced in these glacial systems could ultimately impact Earth\u0027s carbon budget. Results from this research will help scientists (including modelers) refine predictions of the effects of melting glaciers- and attendant exposure of glacial sediment? on atmospheric carbon levels. These results may also contribute to applied research efforts on development of carbon-dioxide removal technologies utilizing principles of rock weathering. In addition to the scientific benefits, this research will involve several students at the undergraduate, graduate, and post-doctoral levels, including science education undergraduates, thus contributing to training of the next-generation STEM workforce.\r\n\r\nPhysical weathering produces fresh surfaces, greatly enhancing specific surface area (SSA) and reactive surface area (RSA) of primary minerals. Quantifying SSA and RSA of sediments is key to determining dissolution and leaching rates during natural weathering, but few data exist on distribution of sediment SA, particularly in glacial and fluvial systems. Pilot data from glacial stream systems in Taylor Valley and Wright Valley (located in the MDV) exhibit remarkably high and variable values in both SSA and RSA, values that in some cases greatly exceed values from muds in temperate glacial systems. This discovery motivates the current research, which aims to investigate the hypothesis that high and variable SAs of muds within Wright and Taylor Valleys reflect textural and/or compositional inheritance from the differing depositional settings within the MDV, biologic controls, dust additions, and/or pedogenic processes. These hypotheses will be tested by sedimentologically, mineralogically, and geochemically characterizing muds from glacially derived sediment deposited in various environments (cold vs. wet based glaciation; fluvial, lacustrine, dust, and drift deposits) and of varying age (Miocene to Modern) from the MDV and quantifying variation of SA and reactivity. Comparisons with analyzed muds from temperate glacial systems will enable polar-temperate comparisons. Analyses will focus on muds of previously collected sediment from the MDVs. Grain size and SSA will be measured by Laser Analysis and N2 adsorption BET, respectively. After carbonate removal, samples will be re-analyzed for SSA, and muds characterized geochemically. Mineralogy and bulk chemistry will also be assessed on co-occurring sand fractions, and textural attributes documented. SSA-normalized dissolution experiments will be used to compare solutes released from sediments to determine RSAs. Results will be integrated with the various sedimentologic and geochemical analyses to test the posed hypotheses. Ultimately, this research should shed light on how weathering in Antarctic systems contributes to global carbon cycling.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; AMD; FIELD INVESTIGATION; USA/NSF; Dry Valleys; SEDIMENT CHEMISTRY; Amd/Us; Antarctica; Weathering", "locations": "Antarctica; Dry Valleys", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Soreghan, Gerilyn; Elwood Madden, Megan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems", "uid": "p0010181", "west": null}, {"awards": "1834986 Ballard, Grant", "bounds_geometry": "POLYGON((165 -77,165.5 -77,166 -77,166.5 -77,167 -77,167.5 -77,168 -77,168.5 -77,169 -77,169.5 -77,170 -77,170 -77.1,170 -77.2,170 -77.3,170 -77.4,170 -77.5,170 -77.6,170 -77.7,170 -77.8,170 -77.9,170 -78,169.5 -78,169 -78,168.5 -78,168 -78,167.5 -78,167 -78,166.5 -78,166 -78,165.5 -78,165 -78,165 -77.9,165 -77.8,165 -77.7,165 -77.6,165 -77.5,165 -77.4,165 -77.3,165 -77.2,165 -77.1,165 -77))", "dataset_titles": "Orthomosaics of Ross Island Penguin Colonies 2019 - 2021", "datasets": [{"dataset_uid": "601612", "doi": "10.15784/601612", "keywords": "Aerial Imagery; Aerial Survey; Antarctica; Biota; Geotiff; Penguin; Photo/video; Photo/Video; Population Count; Ross Island; UAV", "people": "Shah, Kunal; Schmidt, Annie; Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Orthomosaics of Ross Island Penguin Colonies 2019 - 2021", "url": "https://www.usap-dc.org/view/dataset/601612"}], "date_created": "Wed, 12 May 2021 00:00:00 GMT", "description": "New methodologies for the deployment of coordinated unmanned aerial vehicles will be developed with the aim of attaining whole-colony imagery that can be used to characterize nesting habitats of Adelie penguins at Cape Crozier, on Ross Island, Antarctica. This information will be used to test hypotheses regarding relationships between terrain characteristics, nesting density, and breeding success. This population, potentially the largest in the world and at the southern limit of the species\u0027 range, has doubled in size over the past 20 years while most other colonies in the region have remained stable or declined. New information gained from this project will be useful in understanding the potential of climate-driven changes in terrestrial nesting habitats for impacting Adelie penguins in the future. The project will produce, and document, open-source software tools to help automate image processing for automated counting of Adelie penguins. The project will train graduate and undergraduate students and contribute materials to ongoing educational outreach programs based on related penguin science projects. Information gained from this project will contribute towards building robust, cost-effective protocols for monitoring Adelie penguin populations, a key ecosystem indicator identified in the draft Ross Sea Marine Protected Area Research and Monitoring Plan.\r\n\r\nAdelie penguins are important indicators of ecosystem function and change in the Southern Ocean. In addition to facing rapid changes in sea ice and other factors in their pelagic environment, their terrestrial nesting habitat is also changing. Understanding the species\u0027 response to such changes is critical for assessing its ability to adapt to the changing climate. The objective of this project is to test several hypotheses about the influence of fine-scale nesting habitat, nest density, and breeding success of Adelie penguins in the Ross Sea region. To accomplish this, the project will develop algorithms to improve efficiency and safety of surveys by unmanned aerial systems and develop and disseminate an automated image processing workflow. Images collected during several UAV surveys will be used to estimate the number of nesting adults and chicks produced, as well as estimate nesting density in different parts of two colonies on Ross Island, Antarctica, that differ in size by two orders of magnitude. Imagery will be used to generate high resolution digital surface/elevation models that will allow terrain variables like flood risk and terrain complexity to be derived. Combining the surface model with the nest and chick counts at the two colonies will provide relationships between habitat covariates, nest density, and breeding success. The approaches developed will enable Adelie penguin population sizes and potentially several other indicators in the Ross Sea Marine Protected Area Research and Monitoring Plan to be determined and evaluated. The flight control algorithms developed have the potential to be used for many types of surveys, especially when large areas need to be covered in a short period with extreme weather potential and difficult landing options. Aerial images and video will be used to create useable materials to be included in outreach and educational programs. The automated image processing workflow and classification models will be developed as open source software and will be made freely available for others addressing similar wildlife monitoring challenges.", "east": 170.0, "geometry": "POINT(167.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "UAS; Ross Island; USA/NSF; FIELD INVESTIGATION; AMD; UAV; MARINE ECOSYSTEMS; USAP-DC; Amd/Us; Penguin", "locations": "Ross Island", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ballard, Grant; Schmidt, Annie; Schwager, Mac; McKown, Matthew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Does Nest Density Matter? Using Novel Technology to Collect Whole-colony Data on Adelie Penguins.", "uid": "p0010178", "west": 165.0}, {"awards": "1935870 Ballard, Grant; 1935901 Dugger, Katie", "bounds_geometry": "POLYGON((-180 -60,-177 -60,-174 -60,-171 -60,-168 -60,-165 -60,-162 -60,-159 -60,-156 -60,-153 -60,-150 -60,-150 -61.8,-150 -63.6,-150 -65.4,-150 -67.2,-150 -69,-150 -70.8,-150 -72.6,-150 -74.4,-150 -76.2,-150 -78,-153 -78,-156 -78,-159 -78,-162 -78,-165 -78,-168 -78,-171 -78,-174 -78,-177 -78,180 -78,178.5 -78,177 -78,175.5 -78,174 -78,172.5 -78,171 -78,169.5 -78,168 -78,166.5 -78,165 -78,165 -76.2,165 -74.4,165 -72.6,165 -70.8,165 -69,165 -67.2,165 -65.4,165 -63.6,165 -61.8,165 -60,166.5 -60,168 -60,169.5 -60,171 -60,172.5 -60,174 -60,175.5 -60,177 -60,178.5 -60,-180 -60))", "dataset_titles": "Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "datasets": [{"dataset_uid": "601444", "doi": "10.15784/601444", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Mark-Recapture; Monitoring; Penguin; Ross Island", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601444"}], "date_created": "Wed, 12 May 2021 00:00:00 GMT", "description": "Polar regions are experiencing some of the most dramatic effects of climate change resulting in large-scale changes in sea ice cover. Despite this, there are relatively few long-term studies on polar species that evaluate the full scope of these effects. Over the last two decades, this team has conducted globally unique demographic studies of Ad\u00e9lie penguins in the Ross Sea, Antarctica, to explore several potential mechanisms for population change. This five-year project will use penguin-borne sensors to evaluate foraging conditions and behavior and environmental conditions on early life stages of Ad\u00e9lie penguins. Results will help to better understand population dynamics and how populations might respond to future environmental change. To promote STEM literacy, education and public outreach efforts will include multiple activities. The PenguinCam and PenguinScience.com website (impacts of \u003e1 million hits per month and use by \u003e300 classrooms/~10,000 students) will be continued. Each field season will also have \u2018Live From the Penguins\u2019 Skype calls to classes (~120/season). Classroom-ready activities that are aligned with Next Generation Science Standards will be developed with media products and science journal papers translated to grade 5-8 literacy level. The project will also train early career scientists, postdoctoral scholars, graduate students and post-graduate interns. Finally, in partnership with an Environmental Leadership Program, the team will host 2-year Roger Arliner Young Conservation Fellow, which is a program designed to increase opportunities for recent college graduates of color to learn about, engage with, and enter the environmental conservation sector.\r\n", "east": -150.0, "geometry": "POINT(-172.5 -69)", "instruments": null, "is_usap_dc": true, "keywords": "Ross Island; AMD; MARINE ECOSYSTEMS; Amd/Us; Adelie Penguin; USAP-DC; USA/NSF; FIELD SURVEYS", "locations": "Ross Island", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ballard, Grant; Schmidt, Annie; Varsani, Arvind; Dugger, Katie; Orben, Rachael", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Population Growth at the Southern Extreme: Effects of Early Life Conditions on Adelie penguin Individuals and Colonies", "uid": "p0010179", "west": 165.0}, {"awards": "1543459 Dugger, Katie; 1543498 Ballard, Grant; 1543541 Ainley, David", "bounds_geometry": "POLYGON((-180 -60,-177 -60,-174 -60,-171 -60,-168 -60,-165 -60,-162 -60,-159 -60,-156 -60,-153 -60,-150 -60,-150 -61.8,-150 -63.6,-150 -65.4,-150 -67.2,-150 -69,-150 -70.8,-150 -72.6,-150 -74.4,-150 -76.2,-150 -78,-153 -78,-156 -78,-159 -78,-162 -78,-165 -78,-168 -78,-171 -78,-174 -78,-177 -78,180 -78,178.5 -78,177 -78,175.5 -78,174 -78,172.5 -78,171 -78,169.5 -78,168 -78,166.5 -78,165 -78,165 -76.2,165 -74.4,165 -72.6,165 -70.8,165 -69,165 -67.2,165 -65.4,165 -63.6,165 -61.8,165 -60,166.5 -60,168 -60,169.5 -60,171 -60,172.5 -60,174 -60,175.5 -60,177 -60,178.5 -60,-180 -60))", "dataset_titles": "Adelie penguin banding data 1994-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science; Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science; Locations of Adelie penguins from geolocating dive recorders 2017-2019; Penguinscience Data Sharing Website", "datasets": [{"dataset_uid": "601444", "doi": "10.15784/601444", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Mark-Recapture; Monitoring; Penguin; Ross Island", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601444"}, {"dataset_uid": "601443", "doi": "10.15784/601443", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Penguin; Ross Sea; Seabirds", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin banding data 1994-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601443"}, {"dataset_uid": "601482", "doi": "10.15784/601482", "keywords": "Adelie Penguin; Animal Behavior Observation; Antarctica; Biologging; Biota; Foraging Ecology; Geolocator; GPS Data; Migration; Ross Sea; Winter", "people": "Ainley, David; Schmidt, Annie; Lescroel, Amelie; Lisovski, Simeon; Ballard, Grant; Dugger, Katie", "repository": "USAP-DC", "science_program": null, "title": "Locations of Adelie penguins from geolocating dive recorders 2017-2019", "url": "https://www.usap-dc.org/view/dataset/601482"}, {"dataset_uid": "200278", "doi": "", "keywords": null, "people": null, "repository": "California Avian Data Center", "science_program": null, "title": "Penguinscience Data Sharing Website", "url": "https://data.pointblue.org/apps/penguin_science/"}], "date_created": "Tue, 11 May 2021 00:00:00 GMT", "description": "The Ross Sea region of the Southern Ocean is experiencing growing sea ice cover in both extent and duration. These trends contrast those of the well-studied, western Antarctic Peninsula area, where sea ice has been disappearing. Unlike the latter, little is known about how expanding sea ice coverage might affect the regional Antarctic marine ecosystem. This project aims to better understand some of the potential effects of the changing ice conditions on the marine ecosystem using the widely-recognized indicator species - the Ad\u00e9lie Penguin. A four-year effort will build on previous results spanning 19 seasons at Ross Island to explore how successes or failures in each part of the penguin\u0027s annual cycle are effected by ice conditions and how these carry over to the next annual recruitment cycle, especially with respect to the penguin\u0027s condition upon arrival in the spring. Education and public outreach activities will continually be promoted through the PenguinCam and PenguinScience websites (sites with greater than 1 million hits a month) and \"NestCheck\" (a site that is logged-on by \u003e300 classrooms annually that allows students to follow penguin families in their breeding efforts). To encourage students in pursuing educational and career pathways in the Science Technology Engineering and Math fields, the project will also provide stories from the field in a Penguin Journal, develop classroom-ready activities aligned with New Generation Science Standards, increase the availability of instructional presentations as powerpoint files and short webisodes. The project will provide additional outreach activities through local, state and national speaking engagements about penguins, Antarctic science and climate change. The annual outreach efforts are aimed at reaching over 15,000 students through the website, 300 teachers through presentations and workshops, and 500 persons in the general public. The project also will train four interns (undergraduate and graduate level), two post-doctoral researchers, and a science writer/photographer. \u003cbr/\u003e\u003cbr/\u003eThe project will accomplish three major goals, all of which relate to how Ad\u00e9lie Penguins adapt to, or cope with environmental change. Specifically the project seeks to determine 1) how changing winter sea ice conditions in the Ross Sea region affect penguin migration, behavior and survival and alter the carry-over effects (COEs) to subsequent reproduction; 2) the interplay between extrinsic and intrinsic factors influencing COEs over multiple years of an individual\u0027s lifetime; and 3) how local environmental change may affect population change via impacts to nesting habitat, interacting with individual quality and COEs. Retrospective analyses will be conducted using 19 years of colony based data and collect additional information on individually marked, known-age and known-history penguins, from new recruits to possibly senescent individuals. Four years of new information will be gained from efforts based at two colonies (Cape Royds and Crozier), using radio frequency identification tags to automatically collect data on breeding and foraging effort of marked, known-history birds to explore penguin response to resource availability within the colony as well as between colonies (mates, nesting material, habitat availability). Additional geolocation/time-depth recorders will be used to investigate travels and foraging during winter of these birds. The combined efforts will allow an assessment of the effects of penguin behavior/success in one season on its behavior in the next (e.g. how does winter behavior affect arrival time and body condition on subsequent breeding). It is at the individual level that penguins are responding successfully, or not, to ongoing marine habitat change in the Ross Sea region.", "east": -150.0, "geometry": "POINT(-172.5 -69)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; AMD; Adelie Penguin; Amd/Us; FIELD INVESTIGATION; MARINE ECOSYSTEMS; Ross Island; USAP-DC; Penguin", "locations": "Ross Island", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Instrumentation and Support; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ballard, Grant; Ainley, David; Dugger, Katie", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "California Avian Data Center; USAP-DC", "science_programs": null, "south": -78.0, "title": "A Full Lifecycle Approach to Understanding Ad\u00e9lie Penguin Response to Changing Pack Ice Conditions in the Ross Sea.", "uid": "p0010177", "west": 165.0}, {"awards": "1643652 Hofmann, Eileen; 1643618 Arrigo, Kevin", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic biological model output; Antarctic dFe model dyes", "datasets": [{"dataset_uid": "200210", "doi": "10.26008/1912/bco-dmo.782848.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Antarctic dFe model dyes", "url": "https://www.bco-dmo.org/dataset/782848"}, {"dataset_uid": "200211", "doi": "10.26008/1912/bco-dmo.858663.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Antarctic biological model output", "url": "https://www.bco-dmo.org/dataset/858663"}], "date_created": "Thu, 29 Apr 2021 00:00:00 GMT", "description": "Coastal waters surrounding Antarctica represent some of the most biologically rich and most untouched ecosystems on Earth. In large part, this biological richness is concentrated within the numerous openings that riddle the expansive sea ice (these openings are known as polynyas) near the Antarctic continent. These polynyas represent regions of enhanced production known as hot-spots and support the highest animal densities in the Southern Ocean. Many of them are also located adjacent to floating extensions of the vast Antarctic Ice Sheet and receive a substantial amount of meltwater runoff each year during the summer. However, little is known about the specific processes that make these ecosystems so biologically productive. Of the 46 Antarctic coastal polynyas that are presently known, only a handful have been investigated in detail.\r\nThis project will develop ecosystem models for the Ross Sea polynya, Amundsen polynya, and Pine Island polynya; three of the most productive Antarctic coastal polynyas. The primary goal is to use these models to better understand the fundamental physical, chemical, and biological interacting processes and differences in these processes that make these systems so biologically productive yet different in some respects (e.g. size and productivity) during the present day settings. Modeling efforts will also be extended to potentially assess how these ecosystems may have functioned in the past and how they might change in the future under different physical and chemical and climatic settings.\r\nThe project will advance the education of underrepresented minorities through Stanford?s Summer Undergraduate Research in Geoscience and Engineering (SURGE) Program. SURGE will provide undergraduates the opportunity to gain mentored research experiences at Stanford University in engineering and the geosciences. Old Dominion University also will utilize an outreach programs for local public and private schools as well as an ongoing program supporting the Boy Scout Oceanography merit badge program to create outreach and education impacts.\r\n\r\nPolynyas (areas of open water surrounded by sea ice) are disproportionately productive regions of polar ecosystems, yet controls on their high rates of production are not well understood. This project will provide quantitative assessments of the physical and chemical processes that control phytoplankton abundance and productivity within polynyas, how these differ for different polynyas, and how polynyas may change in the future. Of particular interest are the interactions among processes within the polynyas and the summertime melting of nearby ice sheets, including the Thwaites and Pine Island glaciers.\r\nIn this proposed study, we will develop a set of comprehensive, high resolution coupled physical-biological models and implement these for three major, but diverse, Antarctic polynyas. These polynyas, the Ross Sea polynya, the Amundsen polynya, and Pine Island polynya, account for \u003e50% of the total Antarctic polynya production.\r\nThe research questions to be addressed are: 1) What environmental factors exert the greatest control of primary production in polynyas around Antarctica? 2) What are the controlling physics that leads to the heterogeneity of dissolved iron (dFe) supply to the euphotic zone in polynyas around the Antarctic continental shelf? What effect does this have on local rates of primary production? 3) What are the likely changes in the supply of dFe to the euphotic zone in the next several decades due to climate-induced changes in the physics (winds, sea-ice, ice shelf basal melt, cross-shelf exchange, stratification and vertical mixing) and how will this affect primary productivity around the continent?\r\nThe Ross Sea, Amundsen, and Pine Island polynyas are some of the best-sampled polynyas in Antarctica, facilitating model parameterization and validation. Furthermore, these polynyas differ widely in their size, location, sea ice dynamics, relationship to melting ice shelves, and distance from the continental shelf break, making them ideal case studies. For comparison, the western Antarctic Peninsula (wAP), a productive continental shelf where polynyas are a relatively minor contributor to biological production, will also be modeled. Investigating specific processes within different types Antarctic coastal waters will provide a better understand of how these important biological oases function and how they might change under different environmental conditions.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Trace Metal; AMD; PELAGIC; POLYNYAS; PHYTOPLANKTON; MODELS; Amd/Us; USAP-DC; MICROALGAE; USA/NSF; Polynya; TRACE ELEMENTS; ICE SHEETS; Antarctica", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "van Dijken, Gert; Arrigo, Kevin; Dinniman, Michael; Hofmann, Eileen", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Elucidating Environmental Controls of Productivity in Polynas and the Western Antarctic Peninsula", "uid": "p0010175", "west": -180.0}, {"awards": "1543377 Seefeldt, Mark; 1543325 Landolt, Scott", "bounds_geometry": "POLYGON((166.918 -77.8675,167.2997 -77.8675,167.6814 -77.8675,168.0631 -77.8675,168.4448 -77.8675,168.8265 -77.8675,169.2082 -77.8675,169.5899 -77.8675,169.9716 -77.8675,170.3533 -77.8675,170.735 -77.8675,170.735 -77.98145,170.735 -78.0954,170.735 -78.20935,170.735 -78.3233,170.735 -78.43725,170.735 -78.5512,170.735 -78.66515,170.735 -78.7791,170.735 -78.89305,170.735 -79.007,170.3533 -79.007,169.9716 -79.007,169.5899 -79.007,169.2082 -79.007,168.8265 -79.007,168.4448 -79.007,168.0631 -79.007,167.6814 -79.007,167.2997 -79.007,166.918 -79.007,166.918 -78.89305,166.918 -78.7791,166.918 -78.66515,166.918 -78.5512,166.918 -78.43725,166.918 -78.3233,166.918 -78.20935,166.918 -78.0954,166.918 -77.98145,166.918 -77.8675))", "dataset_titles": "Precipitation Observations for the Northwest Ross Ice Shelf - 2017-12 to 2019-11", "datasets": [{"dataset_uid": "601441", "doi": "10.15784/601441", "keywords": "Accumulation; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Meteorology; Precipitation; Ross Ice Shelf; Snow; Snow/ice; Snow/Ice; Weatherstation; Weather Station Data", "people": "Seefeldt, Mark", "repository": "USAP-DC", "science_program": null, "title": "Precipitation Observations for the Northwest Ross Ice Shelf - 2017-12 to 2019-11", "url": "https://www.usap-dc.org/view/dataset/601441"}], "date_created": "Tue, 27 Apr 2021 00:00:00 GMT", "description": "Accurately measuring precipitation in Antarctica is important for purposes such as calculating Antarctica?s mass balance and contribution to global sea level rise, interpreting ice core records, and validating model- and satellite-based precipitation estimates. There is a critical need for reliable, autonomous, long-term measurements of Antarctic precipitation in order to better understand its variability in space in time. Such records over time are essentially absent from the continent, despite their importance. This project will deploy and test instrumentation to measure and record rates of snowfall and blowing snow in Antarctica. \r\n\r\nProject goals are based on installation of four low-power, autonomous Antarctic precipitation systems (APS) co-located at automatic weather station (AWS) sites in the Ross Island region of Antarctica. The APSs are designed with an integrated sensor approach to provide multiple types of observations of snow accumulation types at the test sites. The APSs are designed to construct an accurate timeline of snow accumulation, and to distinguish the water equivalent of fallen precipitation from surface blowing (lofted) snow, a prime confounding factor. The standard suite of instruments to be deployed includes: precipitation gauge with double Alter windshield, laser disdrometer, laser snow height sensor, optical precipitation detector, anemometer at gauge height, and a visible /infrared webcam. These instruments have previously been shown to work well in cold regions applications.", "east": 170.735, "geometry": "POINT(168.8265 -78.43725)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; AMD; Amd/Us; USA/NSF; SNOW; Wind Data; WEATHER STATIONS; Ross Ice Shelf", "locations": "Ross Ice Shelf", "north": -77.8675, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Seefeldt, Mark; Landolt, Scott", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e WEATHER STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.007, "title": "Collaborative Research: Implementing Low-power, Autonomous Observing Systems to Improve the Measurement and Understanding of Antarctic Precipitation", "uid": "p0010173", "west": 166.918}, {"awards": "1246416 Stephen, Ralph; 1246151 Bromirski, Peter", "bounds_geometry": "POLYGON((-180 -77,-179.5 -77,-179 -77,-178.5 -77,-178 -77,-177.5 -77,-177 -77,-176.5 -77,-176 -77,-175.5 -77,-175 -77,-175 -77.4,-175 -77.8,-175 -78.2,-175 -78.6,-175 -79,-175 -79.4,-175 -79.8,-175 -80.2,-175 -80.6,-175 -81,-175.5 -81,-176 -81,-176.5 -81,-177 -81,-177.5 -81,-178 -81,-178.5 -81,-179 -81,-179.5 -81,180 -81,179 -81,178 -81,177 -81,176 -81,175 -81,174 -81,173 -81,172 -81,171 -81,170 -81,170 -80.6,170 -80.2,170 -79.8,170 -79.4,170 -79,170 -78.6,170 -78.2,170 -77.8,170 -77.4,170 -77,171 -77,172 -77,173 -77,174 -77,175 -77,176 -77,177 -77,178 -77,179 -77,-180 -77))", "dataset_titles": "Collaborative Research: Dynamic Response of the Ross Ice Shelf to Wave-Induced Vibrations and Collaborative Research: Mantle Structure and Dynamics of the Ross Sea from a Passive Seismic Deployment on the Ross Ice Shelf. International Federation of Digital Seismograph Networks. ; Dynamic Response of the Ross Ice Shelf to Wave-induced Vibrations 2015/2016, UNAVCO, Inc., GPS/GNSS Observations Dataset", "datasets": [{"dataset_uid": "200209", "doi": "10.7283/58E3-GA46", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Dynamic Response of the Ross Ice Shelf to Wave-induced Vibrations 2015/2016, UNAVCO, Inc., GPS/GNSS Observations Dataset", "url": "https://doi.org/10.7283/58E3-GA46"}, {"dataset_uid": "200207", "doi": "10.7914/SN/XH_2014", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Collaborative Research: Dynamic Response of the Ross Ice Shelf to Wave-Induced Vibrations and Collaborative Research: Mantle Structure and Dynamics of the Ross Sea from a Passive Seismic Deployment on the Ross Ice Shelf. International Federation of Digital Seismograph Networks. ", "url": "http://www.fdsn.org/networks/detail/XH_2014/"}], "date_created": "Thu, 15 Apr 2021 00:00:00 GMT", "description": "This award supports a project intended to discover, through field observations and numerical simulations, how ocean wave-induced vibrations on ice shelves in general, and the Ross Ice Shelf (RIS), in particular, can be used (1) to infer spatial and temporal variability of ice shelf mechanical properties, (2) to infer bulk elastic properties from signal propagation characteristics, and (3) to determine whether the RIS response to infragravity (IG) wave forcing observed distant from the front propagates as stress waves from the front or is \"locally\" generated by IG wave energy penetrating the RIS cavity. The intellectual merit of the work is that ocean gravity waves are dynamic elements of the global ocean environment, affected by ocean warming and changes in ocean and atmospheric circulation patterns. Their evolution may thus drive changes in ice-shelf stability by both mechanical interactions, and potentially increased basal melting, which in turn feed back on sea level rise. Gravity wave-induced signal propagation across ice shelves depends on ice shelf and sub-shelf water cavity geometry (e.g. structure, thickness, crevasse density and orientation), as well as ice shelf physical properties. Emphasis will be placed on observation and modeling of the RIS response to IG wave forcing at periods from 75 to 300 s. Because IG waves are not appreciably damped by sea ice, seasonal monitoring will give insights into the year-round RIS response to this oceanographic forcing. The 3-year project will involve a 24-month period of continuous data collection spanning two annual cycles on the RIS. RIS ice-front array coverage overlaps with a synergistic Ross Sea Mantle Structure (RSMS) study, giving an expanded array beneficial for IG wave localization. The ice-shelf deployment will consist of sixteen stations equipped with broadband seismometers and barometers. Three seismic stations near the RIS front will provide reference response/forcing functions, and measure the variability of the response across the front. A linear seismic array orthogonal to the front will consist of three stations in-line with three RSMS stations. Passive seismic array monitoring will be used to determine the spatial and temporal distribution of ocean wave-induced signal sources along the front of the RIS and estimate ice shelf structure, with the high-density array used to monitor and localize fracture (icequake) activity. The broader impacts include providing baseline measurements to enable detection of ice-shelf changes over coming decades which will help scientists and policy-makers respond to the socio-environmental challenges of climate change and sea-level rise. A postdoctoral scholar in interdisciplinary Earth science will be involved throughout the course of the research. Students at Cuyamaca Community College, San Diego County, will develop and manage a web site for the project to be used as a teaching tool for earth science and oceanography classes, with development of an associated web site on waves for middle school students.\n\r\nUnderstanding and being able to anticipate changes in the glaciological regime of the Ross Ice Shelf (RIS) and West Antarctic Ice Sheet (WAIS) are key to improving sea level rise projections due to ongoing ice mass loss in West Antarctica. The fate of the WAIS is a first-order climate change and global societal issue for this century and beyond that affects coastal communities and coastal infrastructure globally. \r\n\r\nIce shelf--ocean interactions include impacts from tsunami, ocean swell (10-30s period), and very long period ocean waves that impact ice shelves and produce vibrations that induce a variety of seismic signals detected by seismometers buried in the ice shelf surface layer, called firn. To study the wave-induced vibrations in the RIS, an extensive seismic array was deployed from Nov. 2014 to Nov. 2016. This unique seismometer array deployment on an ice shelf made continuous observations of the response of the RIS to ocean wave impacts from ocean swell and very long period waves. An extensive description of the project motivation and background (including photos and videos of the deployment operations), and list of published studies of analyses of the seismic data collected by this project, are available at the project website https://iceshelfvibes.ucsd.edu. \r\n\r\nTwo types of seismic signals detected by the seismic array are most prevalent: flexural gravity waves (plate waves) and icequakes (signals analogous to those from earthquakes but from fracturing of the ice). \r\nLong period ocean waves flex the ice shelf at the same period as the ocean waves, with wave energy at periods greater than ocean swell more efficient at coupling energy into flexing the ice shelf. Termed flexural gravity waves or plate waves (Chen et al., 2018), their wave-induced vibrations can reach 100\u2019s of km from the ice edge where they are excited, with long period wave energy propagating in the water layer below the shelf coupled with the ice shelf flexure. Flexural gravity waves at very long periods (\u003e 300 s period), such as from tsunami impacts (Bromirski et al., 2017), can readily reach grounding zones and may play a role in long-term grounding zone evolution. \r\nSwell-induced icequake activity was found to be most prevalent at the shelf front during the austral summer (January \u2013 March) when seasonal sea ice is absent and the associated damping of swell by sea ice is minimal (Chen et al., 2019). \r\n\r\nIn addition to the seismic array, a 14 station GPS (global positioning system) array was installed during seismic data retrieval and station servicing operations in October-November 2015. The GPS stations, co-located with seismic stations, extended from the shelf front southward to about 415 km at interior station RS18. Due to logistical constraints associated with battery weight during installation, only one station (at DR10) operated year-round. The GPS data collected give a detailed record of changes in iceflow velocity that are in close agreement with the increasing velocity estimates approaching the shelf front from satellite observations. Importantly, the year-round data at DR10 show an unprecedented seasonal cycle of changes in iceflow velocity, with a speed-up in northward (seaward) ice flow during Jan.-May and then a velocity decrease from June-Sep. (returning to the long-term mean flow velocity). This annual ice flow velocity change cycle has been attributed in part to seasonal changes in ice shelf mass (thinning, reducing buttressing) due to melting at the RIS basal (bottom) surface from intrusion of warmer ocean water (Klein et al., 2020). ", "east": 170.0, "geometry": "POINT(177.5 -79)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; GLACIER MOTION/ICE SHEET MOTION; USAP-DC; Amd/Us; AMD; USA/NSF; Iris; Ross Ice Shelf", "locations": "Ross Ice Shelf", "north": -77.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Bromirski, Peter; Gerstoft, Peter; Stephen, Ralph", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "UNAVCO", "repositories": "IRIS; UNAVCO", "science_programs": null, "south": -81.0, "title": "Collaborative Research: Dynamic Response of the Ross Ice Shelf to Wave-induced Vibrations", "uid": "p0010169", "west": -175.0}, {"awards": "1738992 Pettit, Erin C; 1929991 Pettit, Erin C", "bounds_geometry": "POLYGON((-114 -74,-113 -74,-112 -74,-111 -74,-110 -74,-109 -74,-108 -74,-107 -74,-106 -74,-105 -74,-104 -74,-104 -74.2,-104 -74.4,-104 -74.6,-104 -74.8,-104 -75,-104 -75.2,-104 -75.4,-104 -75.6,-104 -75.8,-104 -76,-105 -76,-106 -76,-107 -76,-108 -76,-109 -76,-110 -76,-111 -76,-112 -76,-113 -76,-114 -76,-114 -75.8,-114 -75.6,-114 -75.4,-114 -75.2,-114 -75,-114 -74.8,-114 -74.6,-114 -74.4,-114 -74.2,-114 -74))", "dataset_titles": "AMIGOS-IIIa \"Cavity\" Aquadopp current data Jan 2020 - Mar 2021; AMIGOS-IIIa \"Cavity\" Seabird CTD data Jan 2020 - Dec 2021; AMIGOS-III Cavity and Channel Snow Height and Thermistor Snow Temperature Data; AMIGOS-IIIc \"Channel\" Aquadopp current data Jan 2020 - Mar 2021; AMIGOS-IIIc \"Channel\" Seabird CTD data Jan 2020 - Dec 2021; CTD data from the NBP 19/02 cruise as part of the TARSAN project in the Amundsen Sea during austral summer 2018/2019; Dotson-Crosson Ice Shelf data from a tale of two ice shelves paper; SIIOS Temporary Deployment; Sub-ice-shelf seafloor elevation derived from point-source active-seismic data on Thwaites Eastern Ice Shelf and Dotson Ice Shelf, December 2019 and January 2020; Thwaites Glacier grounding lines for 2014 and 2019/20 from height above flotation; Two-year velocity and strain-rate averages from the Thwaites Eastern Ice Shelf, 2001-2020; Visala WXT520 weather station data at the Cavity and Channel AMIGOS-III sites", "datasets": [{"dataset_uid": "601578", "doi": "10.15784/601578", "keywords": "Antarctica; Dotson Ice Shelf; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology", "people": "Wild, Christian; Segabinazzi-Dotto, Tiago", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Dotson-Crosson Ice Shelf data from a tale of two ice shelves paper", "url": "https://www.usap-dc.org/view/dataset/601578"}, {"dataset_uid": "200321", "doi": "10.5285/e338af5d-8622-05de-e053-6c86abc06489", "keywords": null, "people": null, "repository": "British Oceanographic Data Centre", "science_program": null, "title": "CTD data from the NBP 19/02 cruise as part of the TARSAN project in the Amundsen Sea during austral summer 2018/2019", "url": "https://www.bodc.ac.uk/data/published_data_library/catalogue/10.5285/e338af5d-8622-05de-e053-6c86abc06489/"}, {"dataset_uid": "601544", "doi": "10.15784/601544", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Mooring; Pine Island Bay; Pressure; Salinity; Temperature; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "AMIGOS-IIIa \"Cavity\" Seabird CTD data Jan 2020 - Dec 2021", "url": "https://www.usap-dc.org/view/dataset/601544"}, {"dataset_uid": "601545", "doi": "10.15784/601545", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Mooring; Pine Island Bay; Pressure; Salinity; Temperature; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "AMIGOS-IIIc \"Channel\" Seabird CTD data Jan 2020 - Dec 2021", "url": "https://www.usap-dc.org/view/dataset/601545"}, {"dataset_uid": "601827", "doi": "10.15784/601827", "keywords": "Antarctica; Cryosphere; Dotson Ice Shelf; Thwaites Glacier", "people": "Truffer, Martin; Muto, Atsuhiro; Alley, Karen; Roccaro, Alexander; Pettit, Erin; Scambos, Ted; Wild, Christian; Pomraning, Dale; Wallin, Bruce", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Sub-ice-shelf seafloor elevation derived from point-source active-seismic data on Thwaites Eastern Ice Shelf and Dotson Ice Shelf, December 2019 and January 2020", "url": "https://www.usap-dc.org/view/dataset/601827"}, {"dataset_uid": "601547", "doi": "10.15784/601547", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Mooring; Pine Island Bay; Pressure; Temperature; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "AMIGOS-IIIa \"Cavity\" Aquadopp current data Jan 2020 - Mar 2021", "url": "https://www.usap-dc.org/view/dataset/601547"}, {"dataset_uid": "601548", "doi": "10.15784/601548", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Mooring; Pine Island Bay; Pressure; Temperature; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "AMIGOS-IIIc \"Channel\" Aquadopp current data Jan 2020 - Mar 2021", "url": "https://www.usap-dc.org/view/dataset/601548"}, {"dataset_uid": "601549", "doi": "10.15784/601549", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Pine Island Bay; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Visala WXT520 weather station data at the Cavity and Channel AMIGOS-III sites", "url": "https://www.usap-dc.org/view/dataset/601549"}, {"dataset_uid": "601499", "doi": "10.15784/601499", "keywords": "Amundsen Sea; Antarctica; Glaciology; Grounding Line; Ice Shelf; Thwaites Glacier", "people": "Wild, Christian; Pettit, Erin; Alley, Karen; Scambos, Ted; Truffer, Martin; Muto, Atsu", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Thwaites Glacier grounding lines for 2014 and 2019/20 from height above flotation", "url": "https://www.usap-dc.org/view/dataset/601499"}, {"dataset_uid": "601552", "doi": "10.15784/601552", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Pine Island Bay; Snow Accumulation; Snow Temperature; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "AMIGOS-III Cavity and Channel Snow Height and Thermistor Snow Temperature Data", "url": "https://www.usap-dc.org/view/dataset/601552"}, {"dataset_uid": "200204", "doi": "https://doi.org/10.7914/SN/1L_2019", "keywords": null, "people": null, "repository": "International Federation of Digital Seismograph Networks", "science_program": null, "title": "SIIOS Temporary Deployment", "url": "http://www.fdsn.org/networks/detail/1L_2019/"}, {"dataset_uid": "601478", "doi": "10.15784/601478", "keywords": "Antarctica; Glaciology; Ice Shelf; Ice Velocity; Strain Rate; Thwaites Glacier", "people": "Truffer, Martin; Klinger, Marin; Wallin, Bruce; Alley, Karen; Wild, Christian; Scambos, Ted; Muto, Atsu; Pettit, Erin", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Two-year velocity and strain-rate averages from the Thwaites Eastern Ice Shelf, 2001-2020", "url": "https://www.usap-dc.org/view/dataset/601478"}], "date_created": "Mon, 22 Feb 2021 00:00:00 GMT", "description": "This project contributes to the joint initiative launched by the U.S. National Science Foundation (NSF) and the U.K. Natural Environment Research Council (NERC) to substantially improve decadal and longer-term projections of ice loss and sea-level rise originating from Thwaites Glacier in West Antarctica. Thwaites and neighboring glaciers in the Amundsen Sea Embayment are rapidly losing mass in response to recent climate warming and related changes in ocean circulation. Mass loss from the Amundsen Sea Embayment could lead to the eventual collapse of the West Antarctic Ice Sheet, raising the global sea level by up to 2.5 meters (8 feet) in as short as 500 years. The processes driving the loss appear to be warmer ocean circulation and changes in the width and flow speed of the glacier, but a better understanding of these changes is needed to refine predictions of how the glacier will evolve. One highly sensitive process is the transitional flow of glacier ice from land onto the ocean to become a floating ice shelf. This flow of ice from grounded to floating is affected by changes in air temperature and snowfall at the surface; the speed and thickness of ice feeding it from upstream; and the ocean temperature, salinity, bathymetry, and currents that the ice flows into. The project team will gather new measurements of each of these local environmental conditions so that it can better predict how future changes in air, ocean, or the ice will affect the loss of ice to the ocean in this region. \u003cbr/\u003e \u003cbr/\u003eCurrent and anticipated near-future mass loss from Thwaites Glacier and nearby Amundsen Sea Embayment region is mainly attributed to reduction in ice-shelf buttressing due to sub-ice-shelf melting by intrusion of relatively warm Circumpolar Deep Water into sub-ice-shelf cavities. Such predictions for mass loss, however, still lack understanding of the dominant processes at and near grounding zones, especially their spatial and temporal variability, as well as atmospheric and oceanic drivers of these processes. This project aims to constrain and compare these processes for the Thwaites and the Dotson Ice Shelves, which are connected through upstream ice dynamics, but influenced by different submarine troughs. The team\u0027s specific objectives are to: 1) install atmosphere-ice-ocean multi-sensor remote autonomous stations on the ice shelves for two years to provide sub-daily continuous observations of concurrent oceanic, glaciologic, and atmospheric conditions; 2) measure ocean properties on the continental shelf adjacent to ice-shelf fronts (using seal tagging, glider-based and ship-based surveys, and existing moored and conductivity-temperature-depth-cast data), 3) measure ocean properties into sub-ice-shelf cavities (using autonomous underwater vehicles) to detail ocean transports and heat fluxes; and 4) constrain current ice-shelf and sub-ice-shelf cavity geometry, ice flow, and firn properties for the ice-shelves (using radar, active-source seismic, and gravimetric methods) to better understand the impact of ocean and atmosphere on the ice-sheet change. The team will also engage the public and bring awareness to this rapidly changing component of the cryosphere through a \"Live from the Ice\" social media campaign in which the public can follow the action and data collection from the perspective of tagged seals and autonomous stations.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -104.0, "geometry": "POINT(-109 -75)", "instruments": null, "is_usap_dc": true, "keywords": "Thwaites Glacier; FIELD SURVEYS; GLACIERS/ICE SHEETS", "locations": "Thwaites Glacier", "north": -74.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Truffer, Martin; Scambos, Ted; Muto, Atsu; Heywood, Karen; Boehme, Lars; Hall, Robert; Wahlin, Anna; Lenaerts, Jan; Pettit, Erin", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "British Oceanographic Data Centre; International Federation of Digital Seismograph Networks; USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -76.0, "title": "NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment", "uid": "p0010162", "west": -114.0}, {"awards": "1643795 Mikesell, Thomas", "bounds_geometry": "POLYGON((-134.5 -75,-130.85 -75,-127.2 -75,-123.55 -75,-119.9 -75,-116.25 -75,-112.6 -75,-108.95 -75,-105.3 -75,-101.65 -75,-98 -75,-98 -75.85,-98 -76.7,-98 -77.55,-98 -78.4,-98 -79.25,-98 -80.1,-98 -80.95,-98 -81.8,-98 -82.65,-98 -83.5,-101.65 -83.5,-105.3 -83.5,-108.95 -83.5,-112.6 -83.5,-116.25 -83.5,-119.9 -83.5,-123.55 -83.5,-127.2 -83.5,-130.85 -83.5,-134.5 -83.5,-134.5 -82.65,-134.5 -81.8,-134.5 -80.95,-134.5 -80.1,-134.5 -79.25,-134.5 -78.4,-134.5 -77.55,-134.5 -76.7,-134.5 -75.85,-134.5 -75))", "dataset_titles": "2D shear-wave velocity model across the West Antarctic Rift System from POLENET-ANET seismic data", "datasets": [{"dataset_uid": "601423", "doi": "10.15784/601423", "keywords": "Antarctica; Crust; Moho; Seismic Tomography; Seismology; Seismometer; Shear Wave Velocity; Surface Wave Dispersion; West Antarctica", "people": "Mikesell, Dylan", "repository": "USAP-DC", "science_program": "POLENET", "title": "2D shear-wave velocity model across the West Antarctic Rift System from POLENET-ANET seismic data", "url": "https://www.usap-dc.org/view/dataset/601423"}], "date_created": "Fri, 15 Jan 2021 00:00:00 GMT", "description": "In this project, the researchers processed and analyzed previously acquired seismic data from the POLENET-ANET array (2010-2011) to estimate variations in seismic shear-wave speed beneath the array. This investigation used a passive seismology method call ambient noise tomography, whereby repetitive seismic noise correlation functions were computed from records of Earth\u0027s ambient seismic noise field. The main results indicate a shallower Moho beneath Marie Byrd Land compared to previous studies in the region.", "east": -98.0, "geometry": "POINT(-116.25 -79.25)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; SEISMIC SURFACE WAVES; West Antarctica", "locations": "West Antarctica", "north": -75.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Mordret, Aurelien; Mikesell, Dylan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "POLENET", "south": -83.5, "title": "Collaborative Research: Monitoring Antarctic Ice Sheet Changes with Ambient Seismic Noise Methods", "uid": "p0010155", "west": -134.5}, {"awards": "1842021 Campbell, Seth", "bounds_geometry": "POLYGON((-168 -82,-162.3 -82,-156.6 -82,-150.9 -82,-145.2 -82,-139.5 -82,-133.8 -82,-128.1 -82,-122.4 -82,-116.7 -82,-111 -82,-111 -82.5,-111 -83,-111 -83.5,-111 -84,-111 -84.5,-111 -85,-111 -85.5,-111 -86,-111 -86.5,-111 -87,-116.7 -87,-122.4 -87,-128.1 -87,-133.8 -87,-139.5 -87,-145.2 -87,-150.9 -87,-156.6 -87,-162.3 -87,-168 -87,-168 -86.5,-168 -86,-168 -85.5,-168 -85,-168 -84.5,-168 -84,-168 -83.5,-168 -83,-168 -82.5,-168 -82))", "dataset_titles": "2017 GPR Observations of the Whillans and Mercer Ice Streams; Whillans and Mercer Shear Margin Ice Flow simulation in ISSM", "datasets": [{"dataset_uid": "601404", "doi": "10.15784/601404", "keywords": "Antarctica; Glaciology; Ice Sheet Flow Model; Ice Shelf Dynamics; Mercer Ice Stream; Model Data; Snow/ice; Snow/Ice; Whillans Ice Stream", "people": "Kaluzienski, Lynn", "repository": "USAP-DC", "science_program": null, "title": "Whillans and Mercer Shear Margin Ice Flow simulation in ISSM", "url": "https://www.usap-dc.org/view/dataset/601404"}, {"dataset_uid": "601403", "doi": "10.15784/601403", "keywords": "Antarctica; Crevasses; Glaciology; GPR; GPS; Ice Sheet Flow Model; Ice Shelf Dynamics; Snow/ice; Snow/Ice; Whillans Ice Stream", "people": "Kaluzienski, Lynn", "repository": "USAP-DC", "science_program": null, "title": "2017 GPR Observations of the Whillans and Mercer Ice Streams", "url": "https://www.usap-dc.org/view/dataset/601403"}], "date_created": "Mon, 14 Dec 2020 00:00:00 GMT", "description": "The Siple Coast in West Antarctica has undergone significant glacier changes over the last millenium. Several ice streams--rapidly moving streams of ice bordered by slow-moving ice--exist in this region that feeds into the Ross Ice Shelf. A long-term slowdown of Whillans Ice Stream appears to be occurring, and this is affecting the zone between the Whillans and Mercer Ice Streams. However, the consistency of this slowdown and resulting changes to the shear margin between the two ice streams are unknown. Shear zone stability represents a potentially critical control on mass balance of ice sheets, especially in regions of fast ice flow where basal shear stress is minimal. This project is therefore focused on understanding the spatial and temporal change of ice flow kinematics, shear margin structure, and shear margin location between Whillans and Mercer Ice Streams. A collateral benefit of and driver for this as a RAPID project is to test a method for assessing where crevassing will develop in this zone of steep velocity gradients. Such a method may benefit not only near-term field-project planning in the 2018-19 field season, but also planning for future fieldwork and traverses.\u003cbr/\u003e\u003cbr/\u003eThe team will use velocity estimates derived from available remote sensing datasets to determine transient velocity patterns and shifts in the shear-zone location over the last 20 years. This velocity time series will be incorporated into a large-scale ice-sheet model to estimate ice-sheet susceptibility to changing boundary conditions over the next century based on likely regional ice-flux scenarios. This approach is an extension of recent work conducted by the team that shows promise for predicting areas of changing high strain rates indicative of an active glacier shear margin. The ultimate objectives are to characterize the flow field of merging ice streams over time and investigate lateral boundary migration. This will provide a better understanding of shear-margin control on ice-shelf and up-glacier stability.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -111.0, "geometry": "POINT(-139.5 -84.5)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "FIELD SURVEYS; Whillans Ice Stream; USAP-DC; Amd/Us; USA/NSF; GLACIER MOTION/ICE SHEET MOTION; MODELS; AMD", "locations": "Whillans Ice Stream", "north": -82.0, "nsf_funding_programs": "Polar Special Initiatives; Antarctic Glaciology", "paleo_time": null, "persons": "Campbell, Seth; Koons, Peter", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e MODELS \u003e MODELS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.0, "title": "RAPID Proposal: Constraining kinematics of the Whillans/Mercer Ice Stream Confluence", "uid": "p0010145", "west": -168.0}, {"awards": "1543539 Liwanag, Heather", "bounds_geometry": null, "dataset_titles": "metabolic measurements; Sedation dose and response; TDR and weather data", "datasets": [{"dataset_uid": "601524", "doi": "10.15784/601524", "keywords": "Antarctica; McMurdo Sound; Metabolic Rate; Thermoregulation; Weddell Seal", "people": "Pearson, Linnea", "repository": "USAP-DC", "science_program": null, "title": "metabolic measurements", "url": "https://www.usap-dc.org/view/dataset/601524"}, {"dataset_uid": "601631", "doi": "10.15784/601631", "keywords": "Antarctica; McMurdo Sound; Weddell Seal", "people": "Pearson, Linnea", "repository": "USAP-DC", "science_program": null, "title": "Sedation dose and response", "url": "https://www.usap-dc.org/view/dataset/601631"}, {"dataset_uid": "601435", "doi": "10.15784/601435", "keywords": "Antarctica; McMurdo Sound; Weddell Seal", "people": "Weitzner, Emma; Pearson, Linnea; Liwanag, Heather", "repository": "USAP-DC", "science_program": null, "title": "TDR and weather data", "url": "https://www.usap-dc.org/view/dataset/601435"}], "date_created": "Sat, 12 Dec 2020 00:00:00 GMT", "description": "The transition of young from parental care to independence is a critical stage in the life of many animals. Surviving this stage can be especially challenging for polar mammals where the extreme cold requires extra energy to keep warm, rather than using the majority of energy for growth, development and physical activities. Young Weddell seals (Leptonychotes weddellii) have only weeks to develop the capabilities to survive both on top of the sea ice and within the -1.9\u00b0C seawater where they can forage for food. The project seeks to better understand how Weddell seal pups rapidly develop (within weeks) the capacity to transition between these two extreme environments (that differ greatly in their abilities to conduct heat) and how they budget their energy during the transition. Though the biology and physiology of adult Weddell seals is well studied, the energetic and physiological strategies of pups during development is still unclear. Understanding factors that may affect survival at critical life history events is essential for better understanding factors that might affect marine mammal populations. Weddell seals are the southernmost breeding mammal and are easily recognizable as quintessential Antarctic seals. Determining potential vulnerabilities at critical life stages to change in the Antarctic environment will facilitate the researchers\u0027 ability to not only gain public interest but also communicate how research is revealing ways in which changes are occurring at the poles and how these changes may affect polar ecosystems. By collaborating with the Marine Mammal Center, the project will directly reach the public, through curricular educational materials and public outreach that will impact over 100,000 visitors annually.\u003cbr/\u003e\u003cbr/\u003eTo elucidate the physiological strategies that facilitate the survival of Weddell seal pups from birth to independence, the proposed study examines the development of their thermoregulation and diving capability. To achieve this, the project will determine the mechanisms that Weddell seal pups use to maintain a stable, warm body temperature in air and in water and then examine the development of diving capability as the animals prepare for independent foraging. The researchers will take a fully integrative approach- making assessments from proteins to tissues to the whole-animal level- when investigating both these objectives. To assess the development of thermoregulatory capability, researchers will quantify body insulation, resting metabolic rates in air and in water, muscle thermogenesis (shivering), and body surface temperatures in the field. The project will also assess the development of dive capability by quantifying oxygen storage capacities and measuring early dive behavior. To identify possible cellular mechanisms for how Weddell seals navigate this trade-off during development, the program will quantify several key developmental regulators of increased hypoxic capacity (HIF, VEGF and EPO) using qPCR, as well as follow the proteomic changes of adipose and muscle tissue, which will include abundance changes of metabolic, antioxidant, cytoskeletal, and Ca2+-regulating proteins. The study of the physiological development leading up to the transition to independence in pinnipeds will help researchers better predict the effects of climate change on the distribution and abundance of this species and how this will affect other trophic levels. Environmental changes that alter habitat suitability have been shown to decrease population health, specifically because of declines in juvenile survival.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "MAMMALS; FIELD INVESTIGATION; McMurdo Sound", "locations": "McMurdo Sound", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Liwanag, Heather; Pearson, Linnea; Tomanek, Lars", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "RUI: Growing Up on Ice: Physiological Adaptations and Developmental Plasticity in Weddell Seal Pups Across Two Extreme Physical Environments", "uid": "p0010144", "west": null}, {"awards": "1908399 Bizimis, Michael; 1908548 Feakins, Sarah", "bounds_geometry": "POLYGON((74.787 -67.27617,74.816483 -67.27617,74.845966 -67.27617,74.875449 -67.27617,74.904932 -67.27617,74.934415 -67.27617,74.963898 -67.27617,74.993381 -67.27617,75.022864 -67.27617,75.052347 -67.27617,75.08183 -67.27617,75.08183 -67.31817,75.08183 -67.36017,75.08183 -67.40217,75.08183 -67.44417,75.08183 -67.48617,75.08183 -67.52817,75.08183 -67.57017,75.08183 -67.61217,75.08183 -67.65417,75.08183 -67.69617,75.052347 -67.69617,75.022864 -67.69617,74.993381 -67.69617,74.963898 -67.69617,74.934415 -67.69617,74.904932 -67.69617,74.875449 -67.69617,74.845966 -67.69617,74.816483 -67.69617,74.787 -67.69617,74.787 -67.65417,74.787 -67.61217,74.787 -67.57017,74.787 -67.52817,74.787 -67.48617,74.787 -67.44417,74.787 -67.40217,74.787 -67.36017,74.787 -67.31817,74.787 -67.27617))", "dataset_titles": "Ejtibbett/EOTproxymodel: Proxy Model Comparison for the Eocene-Oligocene Transition [Computational Notebook]; Paleoceanography and biomarker data from the Antarctic Peninsula over the past 37-3 million years; Prydz Bay East Antarctica, biomarkers and pollen, 36-33 million years; Sabrina Coast East Antarctica, Pollen and Biomarker Data from 59-38 million years ago; Southern High Latitude Temperature Proxies from the Late Eocene and Early Oligocene [Dataset]", "datasets": [{"dataset_uid": "200335", "doi": "10.5281/zenodo.7254536", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Southern High Latitude Temperature Proxies from the Late Eocene and Early Oligocene [Dataset]", "url": "https://zenodo.org/record/7254536#.Y2BLgOTMI2w"}, {"dataset_uid": "200317", "doi": "10.25921/n9kg-yw91", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Paleoceanography and biomarker data from the Antarctic Peninsula over the past 37-3 million years", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/35613"}, {"dataset_uid": "200334", "doi": "10.5281/zenodo.7254786", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Ejtibbett/EOTproxymodel: Proxy Model Comparison for the Eocene-Oligocene Transition [Computational Notebook]", "url": "https://zenodo.org/record/7254786#.Y2BLAeTMI2w"}, {"dataset_uid": "200259", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Sabrina Coast East Antarctica, Pollen and Biomarker Data from 59-38 million years ago", "url": "https://www.ncdc.noaa.gov/paleo/study/34772"}, {"dataset_uid": "200206", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Prydz Bay East Antarctica, biomarkers and pollen, 36-33 million years", "url": "https://www.ncdc.noaa.gov/paleo-search/study/32052"}], "date_created": "Sat, 05 Dec 2020 00:00:00 GMT", "description": "The East Antarctic Ice Sheet holds the largest volume of freshwater on the planet, in total enough to raise sea level by almost two hundred feet. Even minor adjustments in the volume of ice stored have major implications for coastlines and climates around the world. The question motivating this project is how did the ice grow to cover the continent over thirty million years ago when Antarctica changed from a warmer environment to an ice-covered southern continent? The seafloor of Prydz Bay, a major drainage basin of the East Antarctic Ice Sheet (EAIS), has been drilled previously to recover sediments dating from millions of years prior to and across the time when inception of continental ice sheets occurred in Antarctica. The last remnants of plant material found as \u0027biomarkers\u0027 in the ocean sediments record the chemical signatures of rain and snowfall that fed the plants and later the expanding glaciers. Sediment carried by glaciers was also deposited on the seafloor and can be analyzed to discover how glaciers flowed across the landscape. Here, the researchers will identify precipitation changes that result from, and drive, ice sheet growth. This study will gather data and further analyze samples from the seafloor sediment archives of the International Ocean Discovery Program\u0027s (IODP) core repositories. Ultimately these findings can help inform temperature-precipitation-ice linkages within climate and ice sheet models. The project will support the training of three female, early career scientists (PhD \u0026 MS students, and research technician) and both PIs and the PhD student will continue their engagement with broadening participation efforts (e.g., Women in Science and Engineering Program; local chapters of Society for the advancement of Native Americans and Chicanos in Science and other access programs) to recruit undergraduate student participants from underrepresented minorities at both campuses and from local community colleges. Antarctic earth science education materials will be assisted by professional illustrations to be open access and used in public education and communication efforts to engage local communities in Los Angeles CA and Columbia SC. \u003cbr/\u003e\u003cbr/\u003eThe researchers at the University of Southern California and the University of South Carolina will together study the penultimate moment of the early Cenozoic greenhouse climate state: the ~4 million years of global cooling that culminated in the Eocene/Oligocene transition (~34 Ma). Significant gaps remain in the understanding of the conditions that preceded ice expansion on Antarctica. In particular, the supply of raw material for ice sheets (i.e., moisture) and the timing, frequency, and duration of precursor glaciations is poorly constrained. This collaborative proposal combines organic and inorganic proxies to examine how Antarctic hydroclimate changed during the greenhouse to icehouse transition. The central hypothesis is that the hydrological cycle weakened as cooling proceeded. Plant-wax hydrogen and carbon isotopes (hydroclimate proxies) and Hf-Nd isotopes of lithogenous and hydrogenous sediments (mechanical weathering proxies) respond strongly and rapidly to precipitation and glacial advance. This detailed and sensitive combined approach will test whether there were hidden glaciations (and/or warm events) that punctuated the pre-icehouse interval. Studies will be conducted on Prydz Bay marine sediment cores in a depositional area for products of weathering and erosion that were (and are) transported through Lambert Graben from the center of Antarctica. The project will yield proxy information about the presence of plants and the hydroclimate of Antarctica and the timing of glacial advance, and is expected to show drying associated with cooling and ice-sheet growth. The dual approach will untangle climate signals from changes in fluvial versus glacial erosion of plant biomarkers. This proposal is potentially transformative because the combination of organic and inorganic proxies can reveal rapid transitions in aridity and glacial expansion, that may have been missed in slower-response proxies and more distal archives. The research is significant as hydroclimate seems to be a key player in the temperature-cryosphere hysteresis.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 75.08183, "geometry": "POINT(74.934415 -67.48617)", "instruments": null, "is_usap_dc": true, "keywords": "MICROFOSSILS; Prydz Bay; PALEOCLIMATE RECONSTRUCTIONS; Sabrina Coast; DROUGHT/PRECIPITATION RECONSTRUCTION; ISOTOPES; AIR TEMPERATURE RECONSTRUCTION", "locations": "Prydz Bay; Sabrina Coast", "north": -67.27617, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Feakins, Sarah; Scher, Howard", "platforms": null, "repo": "Zenodo", "repositories": "NCEI; Zenodo", "science_programs": null, "south": -67.69617, "title": "Collaborative Research: Organic and Inorganic Geochemical Investigation of Hydrologic Change in East Antarctica in the 4 Million Years Before Full Glaciation", "uid": "p0010143", "west": 74.787}, {"awards": "1643873 Hansen, Samantha; 1643798 Emry, Erica", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "GEOSCOPE Network; IU: Global Seismograph Network; Shear Wave Velocity of the Antarctic Upper Mantle from Full Waveform Inversion and Long Period Ambient Seismic Noise; XP (2000-2004): A Broadband Seismic Investigation of Deep Continental Structure Across the East-West Antarctic Boundary ; YT (2007-2023): IPY POLENET-Antarctica: Investigating links between geodynamics and ice sheets; ZJ (2012-2015): Transantarctic Mountains Northern Network ; ZM (2007-2013): A Broadband Seismic Experiment to Image the Lithosphere beneath the Gamburtsev Mountains, East Antarctica", "datasets": [{"dataset_uid": "200171", "doi": "10.7914/SN/YT_2007", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "YT (2007-2023): IPY POLENET-Antarctica: Investigating links between geodynamics and ice sheets", "url": "http://www.fdsn.org/networks/detail/YT_2007/"}, {"dataset_uid": "200172", "doi": "10.7914/SN/ZM_2007", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": " ZM (2007-2013): A Broadband Seismic Experiment to Image the Lithosphere beneath the Gamburtsev Mountains, East Antarctica", "url": "http://www.fdsn.org/networks/detail/ZM_2007/"}, {"dataset_uid": "200173", "doi": "10.7914/SN/ZJ_2012", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "ZJ (2012-2015): Transantarctic Mountains Northern Network ", "url": "http://www.fdsn.org/networks/detail/ZJ_2012/"}, {"dataset_uid": "200168", "doi": "10.18715/GEOSCOPE.G", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "GEOSCOPE Network", "url": "http://geoscope.ipgp.fr/networks/detail/G/"}, {"dataset_uid": "200169", "doi": "10.7914/SN/IU", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IU: Global Seismograph Network", "url": "http://www.fdsn.org/networks/detail/IU/"}, {"dataset_uid": "200170", "doi": "10.7914/SN/XP_2000", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "XP (2000-2004): A Broadband Seismic Investigation of Deep Continental Structure Across the East-West Antarctic Boundary ", "url": "http://www.fdsn.org/networks/detail/XP_2000/"}, {"dataset_uid": "601744", "doi": "10.15784/601744", "keywords": "Ambient Seismic Noise; Antarctica; Full-Waveform Inversion; Seismic Tomography; Shear Wave Velocity; Solid Earth", "people": "Emry, Erica", "repository": "USAP-DC", "science_program": null, "title": "Shear Wave Velocity of the Antarctic Upper Mantle from Full Waveform Inversion and Long Period Ambient Seismic Noise", "url": "https://www.usap-dc.org/view/dataset/601744"}], "date_created": "Thu, 15 Oct 2020 00:00:00 GMT", "description": "Our project is focused on better resolving the three-dimensional Antarctic mantle structure to further understanding of continental tectonics. To accomplish this, we are utilizing a full-waveform tomographic inversion technique that incorporates long-period ambient noise data and which has been shown to more accurately resolve structure than traditional tomographic approaches. The new models have been developed using the Alabama supercomputer facilities in conjunction with software developed at The University of Rhode Island. Our new tomographic results highlight the lithospheric structure beneath the Wilkes and Aurora Subglacial Basins in East Antarctica, where previous rifting episodes and mid-lithospheric discontinuities are being explored. In West Antarctica, the work is elucidating the easternmost extent of the West Antarctic Rift System as well as rifted structure and possible compositional variations within the Weddell Sea. We are also highlighting regions of Antarctica where tomographic resolution is still lacking and where future deployments are needed to improve resolution.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOGRAPHS", "is_usap_dc": true, "keywords": "SEISMIC SURFACE WAVES; USA/NSF; USAP-DC; SEISMOLOGICAL STATIONS; Amd/Us; AMD; POLNET; TECTONICS; Antarctica", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Emry, Erica; Hansen, Samantha", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e SEISMOLOGICAL STATIONS", "repo": "IRIS", "repositories": "IRIS; USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Imaging Seismic Heterogeneity within the Antarctic Mantle with Full Waveform Ambient Noise Tomography", "uid": "p0010139", "west": -180.0}, {"awards": "1141411 Baker, Ian", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Laboratory Experiments with H2SO4-Doped Ice; The Effects of Soluble Impurities on the Flow and Fabric of Polycrystalline Ice", "datasets": [{"dataset_uid": "600380", "doi": "10.15784/600380", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Physical Properties; Snow", "people": "Baker, Ian", "repository": "USAP-DC", "science_program": null, "title": "The Effects of Soluble Impurities on the Flow and Fabric of Polycrystalline Ice", "url": "https://www.usap-dc.org/view/dataset/600380"}, {"dataset_uid": "601081", "doi": "10.15784/601081", "keywords": null, "people": "Hammonds, Kevin", "repository": "USAP-DC", "science_program": null, "title": "Laboratory Experiments with H2SO4-Doped Ice", "url": "https://www.usap-dc.org/view/dataset/601081"}], "date_created": "Fri, 09 Oct 2020 00:00:00 GMT", "description": "This award supports a project to undertake a systematic examination of the effects of soluble impurities, particularly sulfuric acid, on the creep of polycrystalline ice as function of temperature, strain rate and impurity concentration. The working hypothesis is that soluble impurities will increase the flow rate of polycrystalline ice compared to high-purity ice, that this effect will be temperature dependent and that the impurities by affecting the re-crystallization and grain growth will change the fabric of the ice. Both H2SO4-doped and high-purity poly-crystalline ice will be produced by freezing sheets of ice, breaking them up, sieving the ice particles and then sintering them in a mold into fine-grained cylindrical specimens with at least ten grains across their diameter. The resulting microstructures (dislocation structure, grain size and shape, grain boundary character and micro-structural location of the acid) will be characterized using a variety of techniques including: optical microscopy, scanning electron microscopy, including secondary electron imaging, electron backscattered patterns, energy dispersive X-ray spectroscopy, electron channeling contrast imaging, and X-ray topography. The creep of both the H2SO4-doped and the high-purity polycrystalline ice will be undertaken at a range of temperatures and stresses. The ice?s response to the creep deformation (grain boundary sliding, dislocation motion, re-crystallization, grain boundary migration, impurity redistribution) will be studied using a combination of methods. The creep behavior will be modeled and related to the microstructure. Of particular interest is how impurities affect the activation energy for creep. The intellectual merit of the work is that it will lead to a better understanding of glacier ice and will enable glaciologists to model the influence of impurities on the flow and fabric development in polycrystalline ice. The broader impacts of the project include the knowledge that will be gained of the effects of impurities on the flow of ice which will allow paleoclimatologists to better interpret ice core data and will allow scientists developing predictive models to better address the flow of ice sheets under various climate change scenarios. The project will also lead to the education and training of a Ph.D. student, several undergraduates and some high school students. Results from the research will be published in refereed journals. Several undergraduates, typically two per year, will also perform the work. Dartmouth aggressively courts minority students at all degree levels, and we will seek women or minority group undergraduates for this project. The undergraduates will be supported by Dartmouth?s nationally-honored Women In Science Project or by REU funding. The undergraduates? research will integrate closely with the Ph.D. student?s studies. Hanover High School students will also be involved in the project and develop an educational kit to introduce students to the properties of ice. Results from the research will be published in refereed journals and presented at conferences.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; USAP-DC; SNOW/ICE; Amd/Us; LABORATORY; Antarctica; AMD", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Baker, Ian", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "The Effects of Soluble Impurities on the Flow and Fabric of Polycrystalline Ice", "uid": "p0010133", "west": -180.0}, {"awards": "1043623 Miller, Scott", "bounds_geometry": "POLYGON((117.5 -47,120.35 -47,123.2 -47,126.05 -47,128.9 -47,131.75 -47,134.6 -47,137.45 -47,140.3 -47,143.15 -47,146 -47,146 -49.04,146 -51.08,146 -53.12,146 -55.16,146 -57.2,146 -59.24,146 -61.28,146 -63.32,146 -65.36,146 -67.4,143.15 -67.4,140.3 -67.4,137.45 -67.4,134.6 -67.4,131.75 -67.4,128.9 -67.4,126.05 -67.4,123.2 -67.4,120.35 -67.4,117.5 -67.4,117.5 -65.36,117.5 -63.32,117.5 -61.28,117.5 -59.24,117.5 -57.2,117.5 -55.16,117.5 -53.12,117.5 -51.08,117.5 -49.04,117.5 -47))", "dataset_titles": "Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1210; Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1402; Expedition Data", "datasets": [{"dataset_uid": "001414", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1402"}, {"dataset_uid": "001427", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1210"}, {"dataset_uid": "601309", "doi": "10.15784/601309", "keywords": "Air-Sea Flux; Air Temperature; Amundsen Sea; Antarctica; Antarctic Peninsula; Atmosphere; CO2; Flux; Meteorology; NBP1210; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Southern Ocean; Water Temperature; Wind Direction; Wind Speed", "people": "Miller, Scott; Butterworth, Brian", "repository": "USAP-DC", "science_program": null, "title": "Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1210", "url": "https://www.usap-dc.org/view/dataset/601309"}, {"dataset_uid": "601308", "doi": null, "keywords": "Air-Sea Flux; Air Temperature; Antarctica; Atmosphere; CO2; CO2 Concentrations; East Antarctica; Flux; Meteorology; NBP1402; Oceans; Relative Humidity; Salinity; Totten Glacier; Water Measurements; Water Temperature; Weather Station Data; Wind Direction; Wind Speed", "people": "Butterworth, Brian; Miller, Scott", "repository": "USAP-DC", "science_program": null, "title": "Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1402", "url": "https://www.usap-dc.org/view/dataset/601308"}], "date_created": "Fri, 09 Oct 2020 00:00:00 GMT", "description": "Accurate parameterizations of the air-sea fluxes of CO2 into the Southern Ocean, in particular at high wind velocity, are needed to better assess how projections of global climate warming in a windier world could affect the ocean carbon uptake, and alter the ocean heat budget at high latitudes. \u003cbr/\u003e\u003cbr/\u003eAir-sea fluxes of momentum, sensible and latent heat (water vapor) and carbon dioxide (CO2) are to be measured continuously underway on cruises using micrometeorological eddy covariance techniques adapted to ship-board use. The measured gas transfer velocity (K) is then to be related to other parameters known to affect air-sea-fluxes.\u003cbr/\u003e\u003cbr/\u003eA stated goal of this work is the collection of a set of direct air-sea flux measurements at high wind speeds, conditions where parameterization of the relationship of gas exchange to wind-speed remains contentious. The studies will be carried out at sites in the Southern Ocean using the USAP RV Nathaniel B Palmer as measurment platform. Co-located pCO2 data, to be used in the overall analysis and enabling internal consistency checks, are being collected from existing underway systems aboard the USAP research vessel under other NSF awards.", "east": 146.0, "geometry": "POINT(131.75 -57.2)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "HEAT FLUX; DISSOLVED GASES; Antarctica; USAP-DC; NOT APPLICABLE", "locations": "Antarctica", "north": -47.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Miller, Scott", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -67.4, "title": "Air-Sea Fluxes of Momentum, Heat, and Carbon Dioxide at High Wind Speeds in the Southern Ocean", "uid": "p0010137", "west": 117.5}, {"awards": "1644197 Simms, Alexander", "bounds_geometry": "POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))", "dataset_titles": "Electron Microprobe Analysis of feldspar separates from rock and sediment OSL samples from Joinville and Livingston Island Beaches; Granulometry of Joinville and Livingston Island beaches; Ground-Penetrating Radar data from Livingston Island in the Antarctic Peninsula; Ground Penetrating Radar Profiles from Beaches on Joinville Island, Antarctic Peninsula; Joinville and Livingston Islands - rock and sediment OSL ages; OSL data - Joinville and Livingston Islands - Raw data; Radiocarbon Ages from Beaches on Joinville Island, Antarctic Peninsula", "datasets": [{"dataset_uid": "601632", "doi": "10.15784/601632", "keywords": "Antarctica; Joinville Island", "people": "Simms, Alexander", "repository": "USAP-DC", "science_program": null, "title": "Ground Penetrating Radar Profiles from Beaches on Joinville Island, Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601632"}, {"dataset_uid": "601400", "doi": "10.15784/601400", "keywords": "Antarctica; Grain Size; Granulometry; Joinville Island; Livingston Island; LMG0412; Raised Beaches", "people": "Theilen, Brittany; Simms, Alexander", "repository": "USAP-DC", "science_program": null, "title": "Granulometry of Joinville and Livingston Island beaches", "url": "https://www.usap-dc.org/view/dataset/601400"}, {"dataset_uid": "601532", "doi": "10.15784/601532", "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "people": "DeWitt, Regina", "repository": "USAP-DC", "science_program": null, "title": "OSL data - Joinville and Livingston Islands - Raw data", "url": "https://www.usap-dc.org/view/dataset/601532"}, {"dataset_uid": "601531", "doi": "10.15784/601531", "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "people": "DeWitt, Regina", "repository": "USAP-DC", "science_program": null, "title": "Electron Microprobe Analysis of feldspar separates from rock and sediment OSL samples from Joinville and Livingston Island Beaches", "url": "https://www.usap-dc.org/view/dataset/601531"}, {"dataset_uid": "601534", "doi": "10.15784/601534", "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "people": "DeWitt, Regina", "repository": "USAP-DC", "science_program": null, "title": "Joinville and Livingston Islands - rock and sediment OSL ages", "url": "https://www.usap-dc.org/view/dataset/601534"}, {"dataset_uid": "601634", "doi": "10.15784/601634", "keywords": "Antarctica; Joinville Island; Raised Beaches; Sea Level", "people": "Simms, Alexander", "repository": "USAP-DC", "science_program": null, "title": "Radiocarbon Ages from Beaches on Joinville Island, Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601634"}, {"dataset_uid": "601633", "doi": "10.15784/601633", "keywords": "Antarctica; Joinville Island", "people": "Simms, Alexander", "repository": "USAP-DC", "science_program": null, "title": "Ground-Penetrating Radar data from Livingston Island in the Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601633"}], "date_created": "Thu, 08 Oct 2020 00:00:00 GMT", "description": "Glacier ice loss from Antarctica has the potential to lead to a significant rise in global sea level. One line of evidence for accelerated glacier ice loss has been an increase in the rate at which the land has been rising across the Antarctic Peninsula as measured by GPS receivers. However, GPS observations of uplift are limited to the last two decades. One goal of this study is to determine how these newly observed rates of uplift compare to average rates of uplift across the Antarctic Peninsula over a longer time interval. Researchers reconstructed past sea levels using the age and elevation of ancient beaches now stranded above sea level on the low-lying coastal hills of the Antarctica Peninsula and determined the rate of uplift over the last 5,000 years. The researchers analyzed the structure of the beaches using ground-penetrating radar and the characteristics of beach sediments to understand how sea-level rise and past climate changes are recorded in beach deposits. We found that unlike most views of how sea level changed across Antarctica over the last 5,000 years, its history is complex with periods of increasing rates of sea-level fall as well as short periods of potential sea-level rise. We attribute these oscillations in the nature of sea-level change across the Antarctic Peninsula to changes in the ice sheet over the last 5,000 years. These changes in sea level also suggest our understanding of the Earth structure beneath the Antarctic Peninsula need to be revised. The beach deposits themselves also record periods of climate change as reflected in the size and shape of their cobbles. This project has lead to the training of five graduate students, three undergraduate students, and outreach talks to k-12 schools in three communities.", "east": -55.0, "geometry": "POINT(-60 -63)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "Antarctic Peninsula; COASTAL LANDFORMS/PROCESSES; USAP-DC; SEA LEVEL RECONSTRUCTION; South Shetland Islands; AMD; FIELD INVESTIGATION; Amd/Us; USA/NSF", "locations": "South Shetland Islands; Antarctic Peninsula", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Simms, Alexander; DeWitt, Regina", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "uid": "p0010132", "west": -65.0}, {"awards": "1542962 Anderson, Robert", "bounds_geometry": "POLYGON((-171 -57,-170.8 -57,-170.6 -57,-170.4 -57,-170.2 -57,-170 -57,-169.8 -57,-169.6 -57,-169.4 -57,-169.2 -57,-169 -57,-169 -57.72,-169 -58.44,-169 -59.16,-169 -59.88,-169 -60.6,-169 -61.32,-169 -62.04,-169 -62.76,-169 -63.48,-169 -64.2,-169.2 -64.2,-169.4 -64.2,-169.6 -64.2,-169.8 -64.2,-170 -64.2,-170.2 -64.2,-170.4 -64.2,-170.6 -64.2,-170.8 -64.2,-171 -64.2,-171 -63.48,-171 -62.76,-171 -62.04,-171 -61.32,-171 -60.6,-171 -59.88,-171 -59.16,-171 -58.44,-171 -57.72,-171 -57))", "dataset_titles": "Expedition Data of NBP1702; Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean ; Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean (SNOWBIRDS)", "datasets": [{"dataset_uid": "200165", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean (SNOWBIRDS)", "url": "https://www.bco-dmo.org/dataset/813379/data"}, {"dataset_uid": "200126", "doi": "10.7284/907211", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1702", "url": "https://www.rvdata.us/search/cruise/NBP1702"}, {"dataset_uid": "200166", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean ", "url": "https://www.ncdc.noaa.gov/paleo/study/31312"}], "date_created": "Fri, 25 Sep 2020 00:00:00 GMT", "description": "General:\r\nScientists established more than 30 years ago that the climate-related variability of carbon dioxide levels in the atmosphere over Earth\u2019s ice-age cycles was regulated by the ocean. Hypotheses to explain how the ocean that regulates atmospheric carbon dioxide have long been debated, but they have proven to be difficult to test. This project was designed test one leading hypothesis, specifically that the ocean experienced greater density stratification during the ice ages. That is, with greater stratification during the ice ages and the slower replacement of deep water by cold dense water formed near the poles, the deep ocean would have held more carbon dioxide, which is produced by biological respiration of the organic carbon that constantly rains to the abyss in the form of dead organisms and organic debris that sink from the sunlit surface ocean. To test this hypothesis, the degree of ocean stratification during the last ice age and the rate of deep-water replacement was to be constrained by comparing the radiocarbon ages of organisms that grew in the surface ocean and at the sea floor within a critical region around Antarctica, where most of the replacement of deep waters occurs. Completing this work was expected to contribute toward improved models of future climate change. Climate scientists rely on models to estimate the amount of fossil fuel carbon dioxide that will be absorbed by the ocean in the future. Currently the ocean absorbs about 25% of the carbon dioxide produced by burning fossil fuels. Most of this carbon is absorbed in the Southern Ocean (the region around Antarctica). How this will change in the future is poorly known. Models have difficulty representing physical conditions in the Southern Ocean accurately, thereby adding substantial uncertainty to projections of future ocean uptake of carbon dioxide. Results of the proposed study will provide a benchmark to test the ability of models to simulate ocean processes under climate conditions distinctly different from those that occur today, ultimately leading to improvement of the models and to more reliable projections of future absorption of carbon dioxide by the ocean. \r\n\r\nTechnical:\r\nThe project added a research component to an existing scientific expedition to the Southern Ocean, in the region between the Ross Sea and New Zealand, that collected sediment cores at locations down the northern flank of the Pacific-Antarctic Ridge at approximately 170\u00b0W. The goal was to collect sediments at each location deposited since early in the peak of the last ice age. This region is unusual in the Southern Ocean in that sediments deposited during the last ice age contain foraminifera, tiny organisms with calcium carbonate shells, in much greater abundance than in other regions of the Southern Ocean. Foraminifera are widely used as an archive of several geochemical tracers of past ocean conditions. We proposed to compare the radiocarbon age of foraminifera that inhabited the surface ocean with the age of contemporary specimens that grew on the seabed. The difference in age between surface and deep-swelling organisms would have been used to discriminate between two proposed mechanisms of deep water renewal during the ice age: formation in coastal polynyas around the edge of Antarctica, much as occurs today, versus formation by open-ocean convection in deep-water regions far from the continent. If the latter mechanism prevails, then it was expected that surface and deep-dwelling foraminifera would exhibit similar radiocarbon ages. In the case of dominance of deep-water formation in coastal polynyas, one expects to find very different radiocarbon ages in the two populations of foraminifera. In the extreme case of greater ocean stratification during the last ice age, one even expects the surface dwellers to appear to be older than contemporary bottom dwellers because the targeted core sites lie directly under the region where the oldest deep waters outcrop at the surface following their long circuitous transit through the deep ocean. The primary objective of the proposed work was to reconstruct the water mass age structure of the Southern Ocean during the last ice age, which, in turn, is a primary factor that controls the amount of carbon dioxide stored in the deep sea. In addition, the presence of foraminifera in the cores to be recovered provides a valuable resource for many other paleoceanographic applications, such as: 1) the application of nitrogen isotopes to constrain the level of nutrient utilization in the Southern Ocean and, thus, the efficiency of the ocean\u2019s biological pump, 2) the application of neodymium isotopes to constrain the transport history of deep water masses, 3) the application of boron isotopes and boron/calcium ratios to constrain the pH and inorganic carbon system parameters of ice-age seawater, and 4) the exploitation of metal/calcium ratios in foraminifera to reconstruct the temperature (Mg/Ca) and nutrient content (Cd/Ca) of deep waters during the last ice age at a location near their source near Antarctica. \r\n\r\nUnfortunately, the cores were shipped to the core repository in a horizontal orientation and there was sufficient distortion of the sediment that the radiocarbon ages of benthic foraminifera were uninterpretable. Therefore, we report only the radiocarbon dates for planktonic foraminifera as well as the total counts of elemental relative abundance from X-ray Fluorescence analysis of the cores. In addition, we used the expedition as an opportunity to collect water samples from which dissolved concentrations of long-lived isotope of thorium and protactinium were determined. Results from those analyses showed that lateral transport by isopycnal mixing dominates the supply of Pa to the Southern Ocean. We have also developed a new algorithm to correct for supply of Th by isopycnal mixing and thereby derive estimates of dust flux to the Southern Ocean. \r\n", "east": -169.0, "geometry": "POINT(-170 -60.6)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; SEDIMENT CHEMISTRY; South Pacific Ocean; SHIPS", "locations": "South Pacific Ocean", "north": -57.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, Robert; Fleisher, Martin; Pavia, Frank", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "BCO-DMO", "repositories": "BCO-DMO; NCEI; R2R", "science_programs": null, "south": -64.2, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean", "uid": "p0010130", "west": -171.0}, {"awards": "1644187 Tulaczyk, Slawek", "bounds_geometry": "POLYGON((161 -76.9,161.75 -76.9,162.5 -76.9,163.25 -76.9,164 -76.9,164.75 -76.9,165.5 -76.9,166.25 -76.9,167 -76.9,167.75 -76.9,168.5 -76.9,168.5 -77.04,168.5 -77.18,168.5 -77.32,168.5 -77.46,168.5 -77.6,168.5 -77.74,168.5 -77.88,168.5 -78.02,168.5 -78.16,168.5 -78.3,167.75 -78.3,167 -78.3,166.25 -78.3,165.5 -78.3,164.75 -78.3,164 -78.3,163.25 -78.3,162.5 -78.3,161.75 -78.3,161 -78.3,161 -78.16,161 -78.02,161 -77.88,161 -77.74,161 -77.6,161 -77.46,161 -77.32,161 -77.18,161 -77.04,161 -76.9))", "dataset_titles": "ANTAEM project airborne EM resistivity data from McMurdo Region", "datasets": [{"dataset_uid": "601373", "doi": "10.15784/601373", "keywords": "Antarctica; Dry Valleys; Hydrology; Ice Shelf; McMurdo; Permafrost", "people": "Tulaczyk, Slawek", "repository": "USAP-DC", "science_program": null, "title": "ANTAEM project airborne EM resistivity data from McMurdo Region", "url": "https://www.usap-dc.org/view/dataset/601373"}], "date_created": "Sun, 13 Sep 2020 00:00:00 GMT", "description": "In Antarctica, millions of years of freezing have led to the development of hundreds of meters of thick permafrost (i.e., frozen ground). Recent research demonstrated that this slow freezing has trapped and concentrated water into local and regional briny aquifers, many times more salty than seawater. Because salt depresses the freezing point of water, these saline brines are able to persist as liquid water at temperatures well below the normal freezing point of freshwater. Such unusual groundwater systems may support microbial life, supply nutrients to coastal ocean and ice-covered lakes, and influence motion of glaciers. These briny aquifers also represent potential terrestrial analogs for deep life habitats on other planets, such as Mars, and provide a testing ground for the search for extraterrestrial water. Whereas much effort has been invested in understanding the physics, chemistry, and biology of surface and near-surface waters in cold polar regions, it has been comparably difficult to investigate deep subsurface aquifers in such settings. Airborne ElectroMagnetics (AEM) subsurface imaging provides an efficient way for mapping salty groundwater. An international collaboration with the University of Aarhus in Denmark will enable knowledge and skill transfer in AEM techniques that will enhance US polar research capabilities and provide US undergraduates and graduate students with unique training experiences. This project will survey over 1000 km2 of ocean and land near McMurdo Station in Antarctica, and will reveal if cold polar deserts hide a subsurface pool of liquid water. This will have significant implications for understanding cold polar glaciers, ice-covered lakes, frozen ground, and polar microbiology as well as for predictions of their response to future change. Improvements in permafrost mapping techniques and understanding of permafrost and of underlying groundwaters will benefit human use of high polar regions in the Antarctic and the Arctic.\u003cbr/\u003e\u003cbr/\u003eThe project will provide the first integrative system-scale overview of subsurface water distribution and hydrological connectivity in a partly ice-free coastal region of Antarctica, the McMurdo Dry Valleys. Liquid water is relatively scarce in this environment but plays an outsized role by influencing, and integrating, biological, biogeochemical, glaciological, and geological processes. Whereas surface hydrology and its role in ecosystem processes has been thoroughly studied over the last several decades, it has been difficult to map out and characterize subsurface water reservoirs and to understand their interactions with regional lakes, glaciers, and coastal waters. The proposed project builds on the \"proof-of-concept\" use of AEM technology in 2011. Improvements in sensor and data processing capabilities will result in about double the depth of penetration of the subsurface during the new data collection when compared to the 2011 proof-of-concept survey, which reached depths of 300-400m. The first field season will focus on collecting deep soundings with a ground-based system in key locations where: (i) independent constraints on subsurface structure exist from past drilling projects, and (ii) the 2011 resistivity dataset indicates the need for deeper penetration and high signal-to-noise ratios achievable only with a ground-based system. The regional airborne survey will take place during the second field season and will yield subsurface electrical resistivity data from across several valleys of different sizes and different ice cover fractions.", "east": 168.5, "geometry": "POINT(164.75 -77.6)", "instruments": null, "is_usap_dc": true, "keywords": "FROZEN GROUND; GLACIERS/ICE SHEETS; HELICOPTER; GROUND WATER; RIVERS/STREAMS; Dry Valleys", "locations": "Dry Valleys", "north": -76.9, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Earth Sciences", "paleo_time": null, "persons": "Tulaczyk, Slawek; Mikucki, Jill", "platforms": "AIR-BASED PLATFORMS \u003e ROTORCRAFT/HELICOPTER \u003e HELICOPTER", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.3, "title": "Collaborative Research: Antarctic Airborne ElectroMagnetics (ANTAEM) - Revealing Subsurface Water in Coastal Antarctica", "uid": "p0010129", "west": 161.0}, {"awards": "1543453 Lyons, W. Berry; 1543396 Christner, Brent; 1543347 Rosenheim, Brad; 1543405 Leventer, Amy; 1543441 Fricker, Helen; 1543537 Priscu, John", "bounds_geometry": "POLYGON((-163.611 -84.33543,-162.200034 -84.33543,-160.789068 -84.33543,-159.378102 -84.33543,-157.967136 -84.33543,-156.55617 -84.33543,-155.145204 -84.33543,-153.734238 -84.33543,-152.323272 -84.33543,-150.912306 -84.33543,-149.50134 -84.33543,-149.50134 -84.3659157,-149.50134 -84.3964014,-149.50134 -84.4268871,-149.50134 -84.4573728,-149.50134 -84.4878585,-149.50134 -84.5183442,-149.50134 -84.5488299,-149.50134 -84.5793156,-149.50134 -84.6098013,-149.50134 -84.640287,-150.912306 -84.640287,-152.323272 -84.640287,-153.734238 -84.640287,-155.145204 -84.640287,-156.55617 -84.640287,-157.967136 -84.640287,-159.378102 -84.640287,-160.789068 -84.640287,-162.200034 -84.640287,-163.611 -84.640287,-163.611 -84.6098013,-163.611 -84.5793156,-163.611 -84.5488299,-163.611 -84.5183442,-163.611 -84.4878585,-163.611 -84.4573728,-163.611 -84.4268871,-163.611 -84.3964014,-163.611 -84.3659157,-163.611 -84.33543))", "dataset_titles": "Antarctica - PI Continuous - GZ01-WIS_GroundingZone_01 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - GZ13-WIS_GroundingZone_13 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA02-WIS_LAKES_02 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA06-WIS_LAKES_06 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA07-WIS_LAKES_07 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA09-WIS_LAKES_09 P.S. - GPS/GNSS Observations Dataset; Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland; CTD data from Mercer Subglacial Lake and access borehole; Discrete bulk sediment properties data from Mercer Subglacial Lake; Isotopic data from Whillans Ice Stream grounding zone, West Antarctica; Mercer Subglacial Lake radiocarbon and stable isotope data ; Mercer Subglacial Lake (SLM) microbial composition: 16S rRNA genes (Sequence Read Archive; BioProject: PRJNA790995); Mercer Subglacial Lake (SLM) noble gas and isotopic data; Mercer Subglacial Lake water column viral metagenomic sequencing; Salsa sediment cores; Sediment porewater properties data from Mercer Subglacial Lake; Water column biogeochemical data from Mercer Subglacial Lake", "datasets": [{"dataset_uid": "200217", "doi": "10.7283/3JMY-Y504", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA09-WIS_LAKES_09 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/3JMY-Y504"}, {"dataset_uid": "200216", "doi": "10.7283/F8NH-CV04", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA07-WIS_LAKES_07 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/F8NH-CV04"}, {"dataset_uid": "200282", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Mercer Subglacial Lake (SLM) microbial composition: 16S rRNA genes (Sequence Read Archive; BioProject: PRJNA790995)", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA790995"}, {"dataset_uid": "601663", "doi": "10.15784/601663", "keywords": "Antarctica; Carbon; Cell Counts; Geochemistry; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Mercer Subglacial Lake; Microbes; Nutrients; SALSA; Stable Isotopes; Trace Elements; West Antarctic Ice Sheet", "people": "Tranter, Martyn; Priscu, John; Dore, John; Skidmore, Mark; Science Team, SALSA; Hawkings, Jon; Steigmeyer, August; Li, Wei; Barker, Joel", "repository": "USAP-DC", "science_program": null, "title": "Water column biogeochemical data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601663"}, {"dataset_uid": "601472", "doi": "10.15784/601472", "keywords": "Antarctica; Bistatic Radar; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS Data; Greenland; Lake Whillans; Radar; Store Glacier; Whillans Ice Stream; WISSARD", "people": "Peters, Sean; Siegfried, Matthew; Schroeder, Dustin; Bienert, Nicole; Dawson, Eliza; Christoffersen, Poul; MacKie, Emma", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland", "url": "https://www.usap-dc.org/view/dataset/601472"}, {"dataset_uid": "601661", "doi": "10.15784/601661", "keywords": "Antarctica; Carbon; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Iron; Mercer Subglacial Lake; Mineralogy; Particle Size; Physical Properties; SALSA; Sediment Core; Sulfur; West Antarctic Ice Sheet", "people": "Campbell, Timothy; Michaud, Alexander; Hawkings, Jon; Skidmore, Mark; Tranter, Martyn; Venturelli, Ryan A; Science Team, SALSA; Dore, John", "repository": "USAP-DC", "science_program": null, "title": "Discrete bulk sediment properties data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601661"}, {"dataset_uid": "200214", "doi": "10.7283/YW8Z-TK03", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA02-WIS_LAKES_02 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/YW8Z-TK03"}, {"dataset_uid": "200213", "doi": "10.7283/F7BB-JH05", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - GZ13-WIS_GroundingZone_13 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/F7BB-JH05"}, {"dataset_uid": "200212", "doi": "10.7283/PT0Q-JB95", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - GZ01-WIS_GroundingZone_01 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/PT0Q-JB95"}, {"dataset_uid": "601657", "doi": "10.15784/601657", "keywords": "Antarctica; Conductivity; CTD; Depth; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hot Water Drill; Mercer Subglacial Lake; Physical Properties; SALSA; Subglacial Lake; Temperature", "people": "Rosenheim, Brad; Dore, John; Priscu, John; Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "CTD data from Mercer Subglacial Lake and access borehole", "url": "https://www.usap-dc.org/view/dataset/601657"}, {"dataset_uid": "200246", "doi": "", "keywords": null, "people": null, "repository": "OSU-MGR", "science_program": null, "title": "Salsa sediment cores", "url": "https://osu-mgr.org"}, {"dataset_uid": "601498", "doi": "10.15784/601498", "keywords": "Antarctica; Mercer Subglacial Lake; Noble Gas", "people": "Gardner, Christopher B.; Lyons, W. Berry", "repository": "USAP-DC", "science_program": null, "title": "Mercer Subglacial Lake (SLM) noble gas and isotopic data", "url": "https://www.usap-dc.org/view/dataset/601498"}, {"dataset_uid": "601672", "doi": "10.15784/601672", "keywords": "Antarctica; Isotope; Mercer Subglacial Lake; Radiocarbon; Subglacial Lake", "people": "Venturelli, Ryan; Rosenheim, Brad", "repository": "USAP-DC", "science_program": null, "title": "Mercer Subglacial Lake radiocarbon and stable isotope data ", "url": "https://www.usap-dc.org/view/dataset/601672"}, {"dataset_uid": "601664", "doi": "10.15784/601664", "keywords": "Antarctica; Gas; Geochemistry; Glacier; Glaciology; Mercer Subglacial Lake; Methane; SALSA; Sediment Core; West Antarctic Ice Sheet", "people": "Michaud, Alexander; Tranter, Martyn; Steigmeyer, August; Science Team, SALSA; Dore, John; Skidmore, Mark", "repository": "USAP-DC", "science_program": null, "title": "Sediment porewater properties data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601664"}, {"dataset_uid": "601360", "doi": "10.15784/601360", "keywords": "Antarctica; Radiocarbon; Sediment; Whillans Ice Stream", "people": "Venturelli, Ryan A", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Isotopic data from Whillans Ice Stream grounding zone, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/601360"}, {"dataset_uid": "200215", "doi": "10.7283/C503-KS23", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA06-WIS_LAKES_06 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/C503-KS23"}, {"dataset_uid": "200342", "doi": null, "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Mercer Subglacial Lake water column viral metagenomic sequencing", "url": "https://www.ncbi.nlm.nih.gov/biosample/32811410"}], "date_created": "Thu, 16 Jul 2020 00:00:00 GMT", "description": "The Antarctic subglacial environment remains one of the least explored regions on Earth. This project will examine the physical and biological characteristics of Subglacial Lake Mercer, a lake that lies 1200m beneath the West Antarctic Ice Sheet. This study will address key questions relating to the stability of the ice sheet, the subglacial hydrological system, and the deep-cold subglacial biosphere. The education and outreach component aims to widely disseminate results to the scientific community and to the general public through short films, a blog, and a website.\u003cbr/\u003e\u003cbr/\u003eSubglacial Lake Mercer is one of the larger hydrologically active lakes in the southern basin of the Whillans Ice Plain, West Antarctica. It receives about 25 percent of its water from East Antarctica with the remainder originating from West Antarctica, is influenced by drain/fill cycles in a lake immediately upstream (Subglacial Lake Conway), and lies about 100 km upstream of the present grounding line of the Ross Ice Shelf. This site will yield information on the history of the Whillans and Mercer Ice Streams, and on grounding line migration. The integrated study will include direct sampling of basal ice, water, and sediment from the lake in concert with surface geophysical surveys over a three-year period to define the hydrological connectivity among lakes on the Whillans Ice Plain and their flow paths to the sea. The geophysical surveys will furnish information on subglacial hydrology, aid the site selection for hot-water drilling, and provide spatial context for interpreting findings. The hot-water-drilled boreholes will be used to collect basal ice samples, provide access for direct measurement of subglacial physical, chemical, and biological conditions in the water column and sediments, and to explore the subglacial water cavities using a remotely operated vehicle equipped with sensors, cameras, and sampling equipment. Data collected from this study will address the overarching hypothesis \\\"Contemporary biodiversity and carbon cycling in hydrologically-active subglacial environments associated with the Mercer and Whillans ice streams are regulated by the mineralization and cycling of relict marine organic matter and through interactions among ice, rock, water, and sediments\\\". The project will be undertaken by a collaborative team of scientists, with expertise in microbiology, biogeochemistry, hydrology, geophysics, glaciology, marine geology, paleoceanography, and science communication.", "east": -149.50134, "geometry": "POINT(-156.55617 -84.4878585)", "instruments": null, "is_usap_dc": true, "keywords": "SEDIMENTS; Antarctica; ISOTOPES; Subglacial Lake; USAP-DC; VIRUSES; PALEOCLIMATE RECONSTRUCTIONS; BACTERIA/ARCHAEA; LABORATORY; Radiocarbon; Whillans Ice Stream; AMD; SALSA; ECOSYSTEM FUNCTIONS; RADIOCARBON; FIELD INVESTIGATION; ICE MOTION; Mercer Ice Stream; Amd/Us; USA/NSF; GLACIERS/ICE SHEETS", "locations": "Antarctica; Mercer Ice Stream; Whillans Ice Stream", "north": -84.33543, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Instrumentation and Support; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Rosenheim, Brad; Fricker, Helen; Priscu, John; Leventer, Amy; Dore, John; Lyons, W. Berry; Christner, Brent", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "UNAVCO", "repositories": "GenBank; NCBI GenBank; OSU-MGR; UNAVCO; USAP-DC", "science_programs": null, "south": -84.640287, "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "uid": "p0010119", "west": -163.611}, {"awards": "0125602 Padman, Laurence; 0125252 Padman, Laurence", "bounds_geometry": "POLYGON((-180 -40.231,-144 -40.231,-108 -40.231,-72 -40.231,-36 -40.231,0 -40.231,36 -40.231,72 -40.231,108 -40.231,144 -40.231,180 -40.231,180 -45.2079,180 -50.1848,180 -55.1617,180 -60.1386,180 -65.1155,180 -70.0924,180 -75.0693,180 -80.0462,180 -85.0231,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -85.0231,-180 -80.0462,-180 -75.0693,-180 -70.0924,-180 -65.1155,-180 -60.1386,-180 -55.1617,-180 -50.1848,-180 -45.2079,-180 -40.231))", "dataset_titles": "Antarctic Tide Gauge Database, version 1; AntTG_Database_Tools; CATS2008: Circum-Antarctic Tidal Simulation version 2008; CATS2008_v2023: Circum-Antarctic Tidal Simulation 2008, version 2023; pyTMD; TMD_Matlab_Toolbox_v2.5", "datasets": [{"dataset_uid": "200156", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "AntTG_Database_Tools", "url": "https://github.com/EarthAndSpaceResearch/AntTG_Database_Tools"}, {"dataset_uid": "200157", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "TMD_Matlab_Toolbox_v2.5", "url": "https://github.com/EarthAndSpaceResearch/TMD_Matlab_Toolbox_v2.5"}, {"dataset_uid": "200158", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "pyTMD", "url": "https://github.com/tsutterley/pyTMD"}, {"dataset_uid": "601772", "doi": "10.15784/601772", "keywords": "Antarctica; Cryosphere; Inverse Modeling; Model Data; Ocean Currents; Oceans; Sea Surface; Southern Ocean; Tide Model; Tides", "people": "Padman, Laurence; Sutterley, Tyler; Howard, Susan L.; Greene, Chad A.; Erofeeva, Svetlana", "repository": "USAP-DC", "science_program": null, "title": "CATS2008_v2023: Circum-Antarctic Tidal Simulation 2008, version 2023", "url": "https://www.usap-dc.org/view/dataset/601772"}, {"dataset_uid": "601358", "doi": "10.15784/601358", "keywords": "Antarctica; Oceans; Sea Surface Height; Tide Gauges; Tides", "people": "King, Matt; Padman, Laurence; Howard, Susan L.", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Tide Gauge Database, version 1", "url": "https://www.usap-dc.org/view/dataset/601358"}, {"dataset_uid": "601235", "doi": "10.15784/601235", "keywords": "Antarctica; Inverse Modeling; Model Data; Ocean Currents; Sea Surface; Tidal Models; Tides", "people": "Howard, Susan L.; Padman, Laurence; Erofeeva, Svetlana", "repository": "USAP-DC", "science_program": null, "title": "CATS2008: Circum-Antarctic Tidal Simulation version 2008", "url": "https://www.usap-dc.org/view/dataset/601235"}], "date_created": "Tue, 07 Jul 2020 00:00:00 GMT", "description": "The ocean tide is a large component of total variability of ocean surface height and currents in the seas surrounding Antarctica, including under the floating ice shelves. Maximum tidal height range exceeds 7 m (near the grounding line of Rutford Ice Stream) and maximum tidal currents exceed 1 m/s (near the shelf break in the northwest Ross Sea). Tides contribute to several important climate and ecosystems processes including: ocean mixing, production of dense bottom water, flow of warm Circumpolar Deep Water onto the continental shelves, melting at the bases of ice shelves, fracturing of the ice sheet near a glacier or ice stream\u2019s grounding line, production and decay of sea ice, and sediment resuspension. Tide heights and, in particular, currents can change as the ocean background state changes, and as the geometry of the coastal margins of the Antarctic Ice Sheet varies through ice shelf thickness changes and ice-front and grounding-line advances or retreats. For satellite-based studies of ocean surface height and ice shelf thickness changes, tide heights are a source of substantial noise that must be removed. Similarly, tidal currents can also be a substantial noise signal when trying to estimate mean ocean currents from short-term measurements such as from acoustic Doppler current profilers mounted on ships and CTD rosettes. Therefore, tide models play critical roles in understanding current and future ocean and ice states, and as a method for removing tides in various measurements. A paper in Reviews of Geophysics (Padman, Siegfried and Fricker, 2018, see list of project-related publications below) provides a detailed review of tides and tidal processes around Antarctica.\r\n\nThis project provides a gateway to tide models and a database of tide height coefficients at the Antarctic Data Center, and links to toolboxes to work with these models and data.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e GAUGES \u003e TIDE GAUGES", "is_usap_dc": true, "keywords": "Tide Gauges; OCEAN CURRENTS; Sea Surface Height; USAP-DC; GLACIER MOTION/ICE SHEET MOTION; Tides; Antarctica; MODELS; FIELD INVESTIGATION", "locations": "Antarctica", "north": -40.231, "nsf_funding_programs": "Arctic System Science; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Howard, Susan L.; Padman, Laurence; Erofeeva, Svetlana; King, Matt", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e MODELS \u003e MODELS", "repo": "GitHub", "repositories": "GitHub; USAP-DC", "science_programs": null, "south": -90.0, "title": "Ocean Tides around Antarctica and in the Southern Ocean", "uid": "p0010116", "west": -180.0}, {"awards": "1235094 Thurnherr, Andreas", "bounds_geometry": "POLYGON((-19 -19,-18.2 -19,-17.4 -19,-16.6 -19,-15.8 -19,-15 -19,-14.2 -19,-13.4 -19,-12.6 -19,-11.8 -19,-11 -19,-11 -19.4,-11 -19.8,-11 -20.2,-11 -20.6,-11 -21,-11 -21.4,-11 -21.8,-11 -22.2,-11 -22.6,-11 -23,-11.8 -23,-12.6 -23,-13.4 -23,-14.2 -23,-15 -23,-15.8 -23,-16.6 -23,-17.4 -23,-18.2 -23,-19 -23,-19 -22.6,-19 -22.2,-19 -21.8,-19 -21.4,-19 -21,-19 -20.6,-19 -20.2,-19 -19.8,-19 -19.4,-19 -19))", "dataset_titles": "Expedition Data; NBP1406 Expedition data; NBP1508 Expedition data; Processed Current Measurement Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508; Processed Current Measurement, Pressure and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508 (2015); Processed Current Measurement, Pressure, Salinity and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "datasets": [{"dataset_uid": "601353", "doi": null, "keywords": "CTD; CTD Data; Current Measurements; Current Meter; Mid-Ocean Ridge; Mooring; NBP1508; Oceans; Physical Oceanography; Pressure; R/v Nathaniel B. Palmer; Salinity; South Atlantic Ocean; Temperature", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement, Pressure and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508 (2015)", "url": "https://www.usap-dc.org/view/dataset/601353"}, {"dataset_uid": "601354", "doi": "10.15784/601354", "keywords": "Current Measurements; LADCP; Mid-Ocean Ridge; NBP1508; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; South Atlantic Ocean", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "url": "https://www.usap-dc.org/view/dataset/601354"}, {"dataset_uid": "601352", "doi": null, "keywords": "CTD; Mid-Ocean Ridge; Mooring; NBP1508; Oceans; Physical Oceanography; Pressure; R/v Nathaniel B. Palmer; Salinity; South Atlantic Ocean; Temperature", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement, Pressure, Salinity and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "url": "https://www.usap-dc.org/view/dataset/601352"}, {"dataset_uid": "200154", "doi": "10.7284/906708", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1508 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1508"}, {"dataset_uid": "001408", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1406"}, {"dataset_uid": "200153", "doi": "10.7284/903009", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1406 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1406"}], "date_created": "Thu, 02 Jul 2020 00:00:00 GMT", "description": "Overview: In order to close the global overturning circulation, high-density deep- and bottom waters produced at high latitudes must be made less dense and upwell to shallower depths. Available observations from the subtropical South Atlantic indicate that the bulk of the mixing in the deep ocean there takes place over the topographically rough Mid-Atlantic Ridge, in particular in the quasi-regularly spaced \"fracture zone canyons\" corrugating the ridge flanks. There, dense water is advected toward the ridge crest (i.e. upwelled) by persistent along-valley currents that flow down the unidirectional density gradients, which are maintained by strong turbulence (diapycnal mixing). Most of the data on which these inferences are based were collected during the Brazil Basin Tracer Release Experiment (BBTRE) along a single ridge-flank canyon in the western South Atlantic near 22S where previous analyses have shown that both tidal mixing and overflow processes are important. Therefore, it is likely that both processes must be considered in order to understand and parameterize the effects of turbulence and mixing in the canyons corrugating the flanks of all slow-spreading ridges, which make up large fractions of the sea floor, in particular in the Atlantic, Indian and Southern Oceans. The primary aim of this follow-on project is to improve our understanding of the dynamics over the corrugated flanks of slow-spreading mid-ocean ridges. Due to the coarse sampling resolution and choice of station locations it is not possible to answer important questions, such as the relative importance of tidal and sill mixing, from the BBTRE data. Therefore, high-resolution surveys of hydrography, three-dimensional flow, turbulence and mixing will be carried out in two neighboring canyons and over the intervening topographic spur in the BBTRE region to determine the relative contributions of tidal and sill-related mixing. Furthermore, profiling moorings deployed on two nearby sill regions will be used to derive time series of spatially integrated mixing related buoyancy fluxes and to investigate the strong but unexplained sub-inertial variability of the along-canyon flow recorded previously. Additionally, three small moorings will be deployed in saddles between the two canyons to investigate inter-canyon exchange. The data analysis will include available data from previous experiments, including a set of tracer profiles that has not been analyzed before. Intellectual Merit: The corrugated flanks of slow-spreading ridges cover large areas of the sea floor of several major ocean basins. Therefore, understanding the dynamics in the ~100 km of ridge-flank canyons and its effects on the buoyancy and upwelling budget of the abyssal ocean is of global significance. In addition to determining the relative importance of tidal mixing and cross-sill flows in two canyons, the temporal variability of turbulence and mixing from tidal to yearly time scales will be investigated to gain insights into the forcing of the along-canyon flows, the exchange between neighboring canyons, and the eventual fate of the canyon waters. Broader Impacts: It is anticipated that insights gained during this project will improve our understanding of abyssal mixing in many different regions with similar bottom topography and provide the basis for better parameterizations of the effects of turbulence and mixing in large-scale circulation and climate models that cannot resolve these small-scale processes. As part of the project, a graduate student and a post-doctoral researcher will be trained in all aspects of observational physical oceanography, from data acquisition to interpretation. ", "east": -11.0, "geometry": "POINT(-15 -21)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "OCEAN CURRENTS; South Atlantic Ocean; R/V NBP; WATER MASSES", "locations": "South Atlantic Ocean", "north": -19.0, "nsf_funding_programs": null, "paleo_time": null, "persons": "Thurnherr, Andreas", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -23.0, "title": "Collaborative Research: Flow, Turbulence and Mixing in Mid-Ocean Ridge Fracture Zone Canyons", "uid": "p0010114", "west": -19.0}, {"awards": "1745341 Sumner, Dawn", "bounds_geometry": "POLYGON((161.595 -77.527,161.5953 -77.527,161.5956 -77.527,161.5959 -77.527,161.5962 -77.527,161.5965 -77.527,161.5968 -77.527,161.5971 -77.527,161.5974 -77.527,161.5977 -77.527,161.598 -77.527,161.598 -77.5271,161.598 -77.5272,161.598 -77.5273,161.598 -77.5274,161.598 -77.5275,161.598 -77.5276,161.598 -77.5277,161.598 -77.5278,161.598 -77.5279,161.598 -77.528,161.5977 -77.528,161.5974 -77.528,161.5971 -77.528,161.5968 -77.528,161.5965 -77.528,161.5962 -77.528,161.5959 -77.528,161.5956 -77.528,161.5953 -77.528,161.595 -77.528,161.595 -77.5279,161.595 -77.5278,161.595 -77.5277,161.595 -77.5276,161.595 -77.5275,161.595 -77.5274,161.595 -77.5273,161.595 -77.5272,161.595 -77.5271,161.595 -77.527))", "dataset_titles": "GP0191362, Gp0191371; JAAXLU000000000, JAAXLT000000000", "datasets": [{"dataset_uid": "200151", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "JAAXLU000000000, JAAXLT000000000", "url": "https://www.ncbi.nlm.nih.gov/nuccore/JAAXLU000000000"}, {"dataset_uid": "200152", "doi": "", "keywords": null, "people": null, "repository": "IMG Gold", "science_program": null, "title": "GP0191362, Gp0191371", "url": "https://gold.jgi.doe.gov/study?id=Gs0127369"}], "date_created": "Mon, 22 Jun 2020 00:00:00 GMT", "description": "Atmospheric oxygen rose suddenly approximately 2.4 billion years ago after Cyanobacteria evolved the ability to produce oxygen through photosynthesis (oxygenic photosynthesis). This change permanently altered the future of life on Earth, yet little is known about the evolutionary processes leading to it. The Melainabacteria were first discovered in 2013 and are closely related non-photosynthetic relatives of the first group of organisms capable of oxygenic photosynthesis. This project will utilize existing data on metagenomes from microbial mats in Lake Vanda, an ice-covered lake in Antarctica where many sequences of Melainabacteria have been previously identified. \r\n\r\nFrom this genetic information, we identified a new cyanobacterium, named Aurora vandensis, that is sister to all other Cyanobacteria, providing evolutionary insights. In addition, we assessed the metabolic capabilities of the Melainabacteria with good genomic coverage to identify their potential ecological roles. None contain photosynthetic genes, and we are evaluating the evolutionary relationships among the Cyanobacteria and Melainabacteria, particularly with respect to metabolic genes that will allow an advancement in understanding of the evolutionary path that lead to oxygenic photosynthesis on Earth.\r\n\r\nThe project will focus on extracting evolutionary information from the genomic data of Melainabacteria and Sericytochromatia, recently-described groups closely related to but basal to the Cyanobacteria. The characterization of novel members of these groups in samples from Lake Vanda, Antarctica, provide insights into the path and processes involved in the evolution of oxygenic photosynthesis. The research identified a novel cyanobacterial genus that is sister to all other Cyanobacteria, is most closely related to Gloeobacter, and shares evolutionary differences with that genus. Results also show that characterized Melainabacteria lack photosynthesis genes, but their respiration genes provide insight into evolutionary relationships among Melainabacteria and Cyanobacteria. Results provide unexpected constraints. The project focuses on 12 metagenomes, from which Melainabacteria and novel Cyanobacteria bins are annotated and preliminary metabolic pathways will be constructed. The project utilizes full-length sequences of marker genes from across the bacterial domain with a particular focus on taxa that are oxygenic or anoxygenic phototrophs and use the marker genes, to build a rooted \"backbone\" tree. Incomplete or short sequences from the metagenomes are added to the tree using the Evolutionary Placement Algorithm. The researchers built a corresponding phylogenetic tree using a Bayesian framework and compare their topologies. By doing so, the project aims to improve the understanding of the evolution of oxygenic photosynthesis, which caused the most significant change in Earth\u0027s surface chemistry. Specifically, we document a novel and basal cyanobacterium, significantly broader metabolic diversity within the Melainabacteria than has been previously identified, gain significant insights into their metabolic evolution, their evolutionary relationships with the Cyanobacteria, and the evolutionary steps leading to the origin of oxygenic photosynthesis. This research is constraining key evolutionary processes in the origin of oxygenic photosynthesis. It provides the foundation for future studies by indicating where a genomic record of the evolution of oxygenic photosynthesis may be preserved. Results will are being shared with middle school children through the development of scientific lesson plans in collaboration with teachers.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 161.598, "geometry": "POINT(161.5965 -77.5275)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; FIELD INVESTIGATION; CYANOBACTERIA (BLUE-GREEN ALGAE); Lake Vanda; LABORATORY; LAKE/POND; Genetic Analysis", "locations": "Lake Vanda", "north": -77.527, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Sumner, Dawn; Eisen, Jonathan; Tazi, Loubna", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "NCBI GenBank", "repositories": "IMG Gold; NCBI GenBank", "science_programs": null, "south": -77.528, "title": "Evolution of Oxygenic Photosynthesis as Preserved in Melainabacterial Genomes from Lake Vanda, Antarctica", "uid": "p0010112", "west": 161.595}, {"awards": "1543483 Sedwick, Peter", "bounds_geometry": "POLYGON((-180 -66,-179.5 -66,-179 -66,-178.5 -66,-178 -66,-177.5 -66,-177 -66,-176.5 -66,-176 -66,-175.5 -66,-175 -66,-175 -67.2,-175 -68.4,-175 -69.6,-175 -70.8,-175 -72,-175 -73.2,-175 -74.4,-175 -75.6,-175 -76.8,-175 -78,-175.5 -78,-176 -78,-176.5 -78,-177 -78,-177.5 -78,-178 -78,-178.5 -78,-179 -78,-179.5 -78,180 -78,178.5 -78,177 -78,175.5 -78,174 -78,172.5 -78,171 -78,169.5 -78,168 -78,166.5 -78,165 -78,165 -76.8,165 -75.6,165 -74.4,165 -73.2,165 -72,165 -70.8,165 -69.6,165 -68.4,165 -67.2,165 -66,166.5 -66,168 -66,169.5 -66,171 -66,172.5 -66,174 -66,175.5 -66,177 -66,178.5 -66,-180 -66))", "dataset_titles": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle; NBP1704 Expedition Data", "datasets": [{"dataset_uid": "200150", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle", "url": "https://www.bco-dmo.org/project/815403"}, {"dataset_uid": "001363", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1704 Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1704"}], "date_created": "Mon, 22 Jun 2020 00:00:00 GMT", "description": "The waters of the Ross Sea continental shelf are among the most productive in the Southern Ocean, and may comprise a significant regional oceanic sink for atmospheric carbon dioxide. In this region, primary production can be limited by the supply of dissolved iron to surface waters during the growing season. Water-column observations, sampling and measurements are to be carried out in the late autumn-early winter time frame on the Ross Sea continental shelf and coastal polynyas (Terra Nova Bay and Ross Ice Shelf polynyas), in order to better understand what drives the biogeochemical redistribution of micronutrient iron species during the onset of convective mixing and sea-ice formation at this time of year, thereby setting conditions for primary production during the following spring. The spectacular field setting and remote, hostile conditions that accompany the proposed field study present exciting possibilities for STEM education and training. At the K-12 level, the project seeks to support the development of educational outreach materials targeting elementary and middle school students, pre-service science teachers, and in-service science teachers.", "east": 165.0, "geometry": "POINT(175 -72)", "instruments": null, "is_usap_dc": true, "keywords": "POLYNYAS; USAP-DC; NBP1704; Iron; Ross Sea; TRACE ELEMENTS; SALINITY/DENSITY; R/V NBP; MARINE ECOSYSTEMS; BIOGEOCHEMICAL CYCLES", "locations": "Ross Sea", "north": -66.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Sedwick, Peter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "BCO-DMO", "repositories": "BCO-DMO; R2R", "science_programs": null, "south": -78.0, "title": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle", "uid": "p0010111", "west": -175.0}, {"awards": "1744584 Klein, Andrew; 1744570 Galloway, Aaron; 1744602 Iken, Katrin; 1744550 Amsler, Charles", "bounds_geometry": "POLYGON((-70 -61,-69 -61,-68 -61,-67 -61,-66 -61,-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-60 -61.772,-60 -62.544,-60 -63.316,-60 -64.088,-60 -64.86,-60 -65.632,-60 -66.404,-60 -67.176,-60 -67.948,-60 -68.72,-61 -68.72,-62 -68.72,-63 -68.72,-64 -68.72,-65 -68.72,-66 -68.72,-67 -68.72,-68 -68.72,-69 -68.72,-70 -68.72,-70 -67.948,-70 -67.176,-70 -66.404,-70 -65.632,-70 -64.86,-70 -64.088,-70 -63.316,-70 -62.544,-70 -61.772,-70 -61))", "dataset_titles": "Average global horizontal solar irradiance at study sites; Carbon and nitrogen isotope data along a gradient at the Antarctic Peninsula; Computed fetch for project study sites; Five year mean annual and summer sea ice concentration grids for the Western Antarctic Peninsula from AMSR2, National Ice Center Charts and the Sea Ice Index ; Gridded sea ice concentrations from National Ice Center (NIC) Charts 2014-2019 for Western Antarctic Peninsula ; Initial release of code and data associated with Whippo et al. (2024) Fatty acid profiles and stable isotope composition of Antarctic macroalgae: A baseline for a combined biomarker approach in food web studies.; Landsat Sea Ice/Cloud classifications surrounding project study sites; Latitude and longitude data for project study sites; LMG1904 expedition data; Macroalgal species collected along horizontal transect components ; Modelled Solar Irradiance for Western Antarctic Pennisula; Sea Ice Concentration Timeseries for study sites; Underwater transect videos used for community analyses; Underwater video transect community analysis data; VIIRS KD(490) diffuse attenuation coefficients for study sites", "datasets": [{"dataset_uid": "601639", "doi": "10.15784/601639", "keywords": "Antarctica; Antarctic Peninsula; Biota; Fetch; LMG1904; R/v Laurence M. Gould", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Computed fetch for project study sites", "url": "https://www.usap-dc.org/view/dataset/601639"}, {"dataset_uid": "601653", "doi": "10.15784/601653", "keywords": "Antarctica; Antarctic Peninsula; Biota; Carbon; Carbon Isotopes; LMG1904; Nitrogen Isotopes; Oceans", "people": "Iken, Katrin", "repository": "USAP-DC", "science_program": null, "title": "Carbon and nitrogen isotope data along a gradient at the Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601653"}, {"dataset_uid": "601610", "doi": "10.15784/601610", "keywords": "Antarctica; Antarctic Peninsula; Benthic Communities; Biota; Macroalgae; Macroinvertebrates; Oceans; Video Transects", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Underwater transect videos used for community analyses", "url": "https://www.usap-dc.org/view/dataset/601610"}, {"dataset_uid": "601619", "doi": "10.15784/601619", "keywords": "Antarctica; Antarctic Peninsula; Benthic Communities; Biota; Macroalgae; Macroinvertebrates; Oceans; Video Transects", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Underwater video transect community analysis data", "url": "https://www.usap-dc.org/view/dataset/601619"}, {"dataset_uid": "601640", "doi": "10.15784/601640", "keywords": "Antarctica; Biota; Diffuse Attenuation Coefficient; LMG1904; R/v Laurence M. Gould; Turbidity", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "VIIRS KD(490) diffuse attenuation coefficients for study sites", "url": "https://www.usap-dc.org/view/dataset/601640"}, {"dataset_uid": "601725", "doi": "10.15784/601725", "keywords": "Antarctica; Antarctic Peninsula", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Macroalgal species collected along horizontal transect components ", "url": "https://www.usap-dc.org/view/dataset/601725"}, {"dataset_uid": "601641", "doi": "10.15784/601641", "keywords": "Antarctica; Average Global Horizontal Solar Irradiance; Biota; LMG1904; R/v Laurence M. Gould", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Average global horizontal solar irradiance at study sites", "url": "https://www.usap-dc.org/view/dataset/601641"}, {"dataset_uid": "601642", "doi": "10.15784/601642", "keywords": "Antarctica; Antarctic Peninsula; Biota; LMG1904; R/v Laurence M. Gould; Sea Ice Concentration", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Sea Ice Concentration Timeseries for study sites", "url": "https://www.usap-dc.org/view/dataset/601642"}, {"dataset_uid": "601643", "doi": "10.15784/601643", "keywords": "Antarctica; Antarctic Peninsula; LMG1904; National Ice Center Charts; R/v Laurence M. Gould; Sea Ice Concentration", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Gridded sea ice concentrations from National Ice Center (NIC) Charts 2014-2019 for Western Antarctic Peninsula ", "url": "https://www.usap-dc.org/view/dataset/601643"}, {"dataset_uid": "601651", "doi": "10.15784/601651", "keywords": "Antarctica; Antarctic Peninsula; Biota; GIS; GIS Data; LMG1904; R/v Laurence M. Gould; Solar Radiation", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Modelled Solar Irradiance for Western Antarctic Pennisula", "url": "https://www.usap-dc.org/view/dataset/601651"}, {"dataset_uid": "601649", "doi": "10.15784/601649", "keywords": "Antarctica; Antarctic Peninsula; LMG1904; National Ice Center Charts; Sea Ice Concentration", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Five year mean annual and summer sea ice concentration grids for the Western Antarctic Peninsula from AMSR2, National Ice Center Charts and the Sea Ice Index ", "url": "https://www.usap-dc.org/view/dataset/601649"}, {"dataset_uid": "200147", "doi": "10.7284/908260", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "LMG1904 expedition data", "url": "https://www.rvdata.us/search/cruise/LMG1904"}, {"dataset_uid": "601330", "doi": "10.15784/601330", "keywords": "Antarctica; Antarctic Peninsula; Biota; LMG1904; R/v Laurence M. Gould; Sample Location", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Latitude and longitude data for project study sites", "url": "https://www.usap-dc.org/view/dataset/601330"}, {"dataset_uid": "200402", "doi": "10.5281/zenodo.10524919", "keywords": null, "people": null, "repository": "Zendo", "science_program": null, "title": "Initial release of code and data associated with Whippo et al. (2024) Fatty acid profiles and stable isotope composition of Antarctic macroalgae: A baseline for a combined biomarker approach in food web studies.", "url": "https://zenodo.org/records/10524920"}, {"dataset_uid": "601654", "doi": "10.15784/601654", "keywords": "Antarctica; Antarctic Peninsula; GIS; LANDSAT; LMG1904; Remote Sensing; R/v Laurence M. Gould", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Landsat Sea Ice/Cloud classifications surrounding project study sites", "url": "https://www.usap-dc.org/view/dataset/601654"}], "date_created": "Thu, 04 Jun 2020 00:00:00 GMT", "description": "The western Antarctic Peninsula has become a model for understanding cold water communities and how they may be changing in Antarctica and elsewhere. Brown macroalgae (seaweeds) form extensive undersea forests in the northern portion of this region where they play a key role in providing both physical structure and a food (carbon) source for shallow water communities. Yet between Anvers Island (64 degrees S latitude) and Adelaide Island (67 S latitude) these macroalgae become markedly less abundant and diverse. This is probably because the habitat to the south is covered by more sea ice for a longer period, and the sea ice reduces the amount of light that reaches the algae. The reduced macroalgal cover undoubtedly impacts other organisms in the food web, but the ways in which it alters sea-floor community processes and organization is unknown. This project will quantitatively document the macroalgal communities at multiple sites between Anvers and Adelaide Islands using a combination of SCUBA diving, video surveys, and algal collections. Sea ice cover, light levels, and other environmental parameters on community structure will be modelled to determine which factors have the largest influence. Impacts on community structure, food webs, and carbon flow will be assessed through a mixture of SCUBA diving and video surveys. Broader impacts include the training of graduate students and a postdoctoral researcher, as well as numerous informal public education activities including lectures, presentations to K-12 groups, and a variety of social media-based outreach.\u003cbr/\u003e\u003cbr/\u003eMacroalgal communities are more abundance and diverse to the north along the Western Antarctic Peninsula, perhaps due to the greater light availability that is associated with shorter period of sea-ice cover. This project will determine the causes and community level consequence of this variation in algal community structure. First, satellite data on sea ice extent and water turbidity will be used to select study sites between 64 S and 69 S where the extent of annual sea ice cover is the primary factor influencing subsurface light levels. Then, variations in macroalgal cover across these study sites will be determined by video line-transect surveys conducted by SCUBA divers. The health, growth, and physiological status of species found at the different sites will be determined by quadrat sampling. The relative importance of macroalgal-derived carbon to the common invertebrate consumers in the foodweb will be assessed with stable isotope and fatty acid biomarker techniques. This will reveal how variation in macroalgal abundance and species composition across the sea ice cover gradient impacts sea floor community composition and carbon flow throughout the food web. In combination, this work will facilitate predictions of how the ongoing reductions in extent and duration of sea ice cover that is occurring in the region as a result of global climate change will impact the structure of nearshore benthic communities.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -60.0, "geometry": "POINT(-65 -64.86)", "instruments": null, "is_usap_dc": true, "keywords": "COASTAL; R/V LMG; MACROALGAE (SEAWEEDS); BENTHIC; USAP-DC; Antarctic Peninsula", "locations": "Antarctic Peninsula", "north": -61.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Amsler, Charles; McClintock, James; Iken, Katrin; Galloway, Aaron; Klein, Andrew", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "USAP-DC", "repositories": "R2R; USAP-DC; Zendo", "science_programs": null, "south": -68.72, "title": "Collaborative Research: Sea ice as a driver of Antarctic benthic macroalgal community composition and nearshore trophic connectivity", "uid": "p0010104", "west": -70.0}, {"awards": "1744883 Wiens, Douglas", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "ANT-20: A 3D seismic model of the upper mantle and transition zone structure beneath Antarctica and the surrounding southern oceans; CWANT-PSP: A 3-D shear velocity model from a joint inversion of receiver functions and surface wave dispersion derived from ambient noise and teleseismic earthquakes.", "datasets": [{"dataset_uid": "200179", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "ANT-20: A 3D seismic model of the upper mantle and transition zone structure beneath Antarctica and the surrounding southern oceans", "url": "http://ds.iris.edu/ds/products/emc-ant-20/"}, {"dataset_uid": "200178", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "CWANT-PSP: A 3-D shear velocity model from a joint inversion of receiver functions and surface wave dispersion derived from ambient noise and teleseismic earthquakes.", "url": "http://ds.iris.edu/ds/products/emc-cwant-psp/"}], "date_created": "Tue, 02 Jun 2020 00:00:00 GMT", "description": "The geological structure and history of Antarctica remains poorly understood because much of the continental crust is covered by ice. Here, the PIs will analyze over 15 years of seismic data recorded by numerous projects in Antarctica to develop seismic structural models of the continent. The seismic velocity models will reveal features including crustal thinning due to rifting in West Antarctica, the structures associated with mountain building, and the boundaries between different tectonic blocks. The models will be compared to continents that are better understood geologically to constrain the tectonic evolution of Antarctica. In addition, the work will provide better insight into how the solid earth interacts with and influences the development of the ice sheet. Surface heat flow will be mapped and used to identify regions in Antarctica with potential melting at the base of the ice sheet. This melt can lead to reduced friction and lower resistance to ice sheet movement. The models will help to determine whether the earth response to ice mass changes occurs over decades, hundreds, or thousands of years. Estimates of mantle viscosity calculated from the seismic data will be used to better understand the pattern and timescales of the response of the solid earth to changes in ice mass in various parts of Antarctica.\u003cbr/\u003e\u003cbr/\u003eThe study will advance our knowledge of the structure of Antarctica by constructing two new seismic models and a thermal model using different but complementary methodologies. Because of the limitations of different seismic analysis methods, efforts will be divided between a model seeking the highest possible resolution within the upper 200 km depth in the well instrumented region (Bayesian Monte-Carlo joint inversion), and another model determining the structure of the entire continent and surrounding oceans extending through the mantle transition zone (adjoint full waveform inversion). The Monte-Carlo inversion will jointly invert Rayleigh wave group and phase velocities from earthquakes and ambient noise correlation along with P-wave receiver functions and Rayleigh H/V ratios. The inversion will be done in a Bayesian framework that provides uncertainty estimates for the structural model. Azimuthal anisotropy will be determined from Rayleigh wave velocities, providing constraints on mantle fabric and flow patterns. The seismic data will also be inverted for temperature structure, providing estimates of lithospheric thickness and surface heat flow. The larger-scale model will cover the entire continent as well as the surrounding oceans, and will be constructed using an adjoint inversion of phase differences between three component seismograms and synthetic seismograms calculated in a 3D earth model using the spectral element method. This model will fit the entire waveforms, including body waves and both fundamental and higher mode surface waves. Higher resolution results will be obtained by using double-difference methods and by incorporating Green\u0027s functions from ambient noise cross-correlation, and solving for both radial and azimuthal anisotropy.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USA/NSF; Carbon Cycle; SEISMIC PROFILE; Seismology; Southern Ocean; Amd/Us; Antarctica; West Antarctica; MODELS; SEISMIC SURFACE WAVES; AMD; TECTONICS; USAP-DC", "locations": "Antarctica; West Antarctica; Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Wiens, Douglas; Shen, Weisen", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -90.0, "title": "Comprehensive Seismic and Thermal Models for Antarctica and the Southern Oceans: A Synthesis of 15-years of Seismic Exploration", "uid": "p0010103", "west": -180.0}, {"awards": "1743643 Passchier, Sandra", "bounds_geometry": null, "dataset_titles": "Major and trace element analyses of Eocene-Oligocene marine sediments from ODP Site 696, South Orkney Microcontinent; Particle-size distributions of Eocene-Oligocene sediment from ODP Site 696, South Orkney Microcontinent", "datasets": [{"dataset_uid": "601582", "doi": "10.15784/601582", "keywords": "Antarctica; Glaciation; IODP 650; IODP 696; Paleoceanography; Provenance; Sediment Core Data; Weathering; Weddell Sea", "people": "Lepp, Allison; Passchier, Sandra; States, Abbey; Li, Xiaona; Hojnacki, Victoria", "repository": "USAP-DC", "science_program": null, "title": "Major and trace element analyses of Eocene-Oligocene marine sediments from ODP Site 696, South Orkney Microcontinent", "url": "https://www.usap-dc.org/view/dataset/601582"}, {"dataset_uid": "601581", "doi": "10.15784/601581", "keywords": "Antarctica; Glaciation; IODP 696; Marine Geoscience; Marine Sediments; Paleoceanography; Sediment Core Data; Weddell Sea", "people": "Passchier, Sandra; Light, Jennifer; Horowitz Castaldo, Josie; Lepp, Allison", "repository": "USAP-DC", "science_program": null, "title": "Particle-size distributions of Eocene-Oligocene sediment from ODP Site 696, South Orkney Microcontinent", "url": "https://www.usap-dc.org/view/dataset/601581"}], "date_created": "Tue, 26 May 2020 00:00:00 GMT", "description": "Abstract (non-technical)\u003cbr/\u003eSea level rise is a problem of global importance and it is increasingly affecting the tens of millions of Americans living along coastlines. The melting of glaciers in mountain areas worldwide in response to global warming is a major cause of sea level rise and increases in nuisance coastal flooding. However, the world\u0027s largest land-based ice sheets are situated in the Polar Regions and their response under continued warming is very difficult to predict. One reason for this uncertainty is a lack of observations of ice behavior and melt under conditions of warming, as it is a relatively new global climate state lasting only a few generations so far. Researchers will investigate ice growth on Antarctica under past warm conditions using geological archives embedded in the layers of sand and mud under the sea floor near Antarctica. By peeling back at the layers beneath the seafloor investigators can read the history book of past events affecting the ice sheet. The Antarctic continent on the South Pole, carries the largest ice mass in the world. The investigator\u0027s findings will substantially improve scientists understanding of the response of ice sheets to global warming and its effect on sea level rise.\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eAbstract (technical)\u003cbr/\u003eThe melt of land based ice is raising global sea levels with at present only minor contributions from polar ice sheets. However, the future role of polar ice sheets in climate change is one of the most critical uncertainties in predictions of sea level rise around the globe. The respective roles of oceanic and atmospheric greenhouse forcing on ice sheets are poorly addressed with recent measurements of polar climatology, because of the extreme rise in greenhouse forcing the earth is experiencing at this time. Data on the evolution of the West Antarctic ice sheet is particularly sparse. To address the data gap, researchers will reconstruct the timing and spatial distribution of Antarctic ice growth through the last greenhouse to icehouse climate transition around 37 to 33 Ma. They will collect sedimentological and geochemical data on core samples from a high-latitude paleoarchive to trace the shutdown of the chemical weathering system, the onset of glacial erosion, ice rafting, and sea ice development, as East and West Antarctic ice sheets coalesced in the Weddell Sea sector. Their findings will lead to profound increases in the understanding of the role of greenhouse forcing in ice sheet development and its effect on the global climate system.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; AMD; SEDIMENTS; LABORATORY; USA/NSF; USAP-DC; Weddell Sea", "locations": "Weddell Sea", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Passchier, Sandra", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition", "uid": "p0010101", "west": null}, {"awards": null, "bounds_geometry": null, "dataset_titles": "J-9 Drill Hole Temperatures", "datasets": [{"dataset_uid": "601316", "doi": "10.15784/601316", "repository": "USAP-DC", "science_program": null, "title": "J-9 Drill Hole Temperatures", "url": "http://www.usap-dc.org/view/dataset/601316"}], "date_created": "Tue, 05 May 2020 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Ross Ice Shelf", "locations": "Antarctica; Ross Ice Shelf", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Clough, John", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "9978236 Bell, Robin", "bounds_geometry": "POLYGON((101 -75.5,101.9 -75.5,102.8 -75.5,103.7 -75.5,104.6 -75.5,105.5 -75.5,106.4 -75.5,107.3 -75.5,108.2 -75.5,109.1 -75.5,110 -75.5,110 -75.85,110 -76.2,110 -76.55,110 -76.9,110 -77.25,110 -77.6,110 -77.95,110 -78.3,110 -78.65,110 -79,109.1 -79,108.2 -79,107.3 -79,106.4 -79,105.5 -79,104.6 -79,103.7 -79,102.8 -79,101.9 -79,101 -79,101 -78.65,101 -78.3,101 -77.95,101 -77.6,101 -77.25,101 -76.9,101 -76.55,101 -76.2,101 -75.85,101 -75.5))", "dataset_titles": "SOAR-Lake Vostok Survey airborne radar data; SOAR-Lake Vostok Survey bed elevation data; SOAR-Lake Vostok Survey Gravity data; SOAR-Lake Vostok Survey ice thickness data; SOAR-Lake Vostok survey magnetic anomaly data; SOAR-Lake Vostok Survey surface elevation data", "datasets": [{"dataset_uid": "601295", "doi": "10.1594/IEDA/306563", "keywords": "Airborne Gravity; Airplane; Antarctica; East Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Lake Vostok; Potential Field; Solid Earth", "people": "Bell, Robin; Studinger, Michael S.", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey Gravity data", "url": "https://www.usap-dc.org/view/dataset/601295"}, {"dataset_uid": "601296", "doi": " 10.1594/IEDA/306564", "keywords": "Airborne Magnetic; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Lake Vostok; Magnetic; Magnetic Anomaly; Magnetometer; Potential Field; SOAR; Solid Earth", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok survey magnetic anomaly data", "url": "https://www.usap-dc.org/view/dataset/601296"}, {"dataset_uid": "601297", "doi": "10.1594/IEDA/306567", "keywords": "Airborne Laser Altimeters; Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Sheet; Ice Stratigraphy; Ice Thickness; Ice Thickness Distribution; Lake Vostok; Radar; Radar Altimetry; Radar Echo Sounder; SOAR; Subglacial Lake", "people": "Bell, Robin; Studinger, Michael S.", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey ice thickness data", "url": "https://www.usap-dc.org/view/dataset/601297"}, {"dataset_uid": "601299", "doi": "10.1594/IEDA/306565", "keywords": "Airborne Laser Altimeters; Airborne Laser Altimetry; Airborne Radar; Airplane; Antarctica; Bed Elevation; Bedrock Elevation; Digital Elevation Model; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Lake Vostok; Radar; Radar Echo Sounder; SOAR", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey bed elevation data", "url": "https://www.usap-dc.org/view/dataset/601299"}, {"dataset_uid": "601298", "doi": "10.1594/IEDA/306566", "keywords": "Airborne Altimetry; Airborne Laser Altimeters; Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Ice Sheet Elevation; Ice Surface; Lake Vostok; Radar Echo Sounder; SOAR; Surface Elevation", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey surface elevation data", "url": "https://www.usap-dc.org/view/dataset/601298"}, {"dataset_uid": "601300", "doi": "10.1594/IEDA/306568", "keywords": "Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Lake Vostok; Navigation; Radar; SOAR; Subglacial Lakes", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey airborne radar data", "url": "https://www.usap-dc.org/view/dataset/601300"}], "date_created": "Fri, 24 Apr 2020 00:00:00 GMT", "description": "This award, provided by the Office of Polar Programs under the Life in Extreme Environments (LExEn) Program, supports a geophysical study of Lake Vostok, a large lake beneath the East Antarctic Ice Sheet. \u003cbr/\u003e\u003cbr/\u003eSubglacial ecosystems, in particular subglacial lake ecosystems are extreme oligotrophic environments. These environments, and the ecosystems which may exist within them, should provide key insights into a range of fundamental questions about the development of Earth and other bodies in the Solar System including: 1) the processes associated with rapid evolutionary radiation after the extensive Neoproterozoic glaciations; 2) the overall carbon cycle through glacial and interglacial periods; and 3) the possible adaptations organisms may require to thrive in environments such as on Europa, the ice covered moon of Jupiter. Over 70 subglacial lakes have been identified beneath the 3-4 kilometer thick ice of Antarctica. One lake, Lake Vostok, is sufficiently large to be clearly identified from space with satellite altimetry. Lake Vostok is similar to Lake Ontario in area but with a much larger volume including measured water depths of 600 meters. The overlying ice sheet is acting as a conveyer belt continually delivering new water, nutrients, gas hydrates, sediments and microbes as the ice sheet flows across the lake. \u003cbr/\u003e\u003cbr/\u003eThe goal of this program is to determine the fundamental boundary conditions for this subglacial lake as an essential first step toward understanding the physical processes within the lake. An aerogeophysical survey over the lake and into the surrounding regions will be acquired to meet this goal. This data set includes gravity, magnetic, laser altimetry and ice penetrating radar data and will be used to compile a basic set of ice surface elevation, subglacial topography, gravity and magnetic anomaly maps. \u003cbr/\u003e\u003cbr/\u003ePotential field methods widely used in the oil industry will be modified to estimate the subglacial topography from gravity data where the ice penetrating radar will be unable to recover the depth of the lake. A similar method can be modified to estimate the thickness of the sediments beneath the lake from magnetic data. These methods will be tested and applied to subglacial lakes near South Pole prior to the Lake Vostok field campaign and will provide valuable comparisons to the planned survey. Once the methods have been adjusted for the Lake Vostok application, maps of the water cavity and sediment thickness beneath the lake will be produced.\u003cbr/\u003e\u003cbr/\u003eThese maps will become tools to explore the geologic origin of the lake. The two endmember models are, first, that the lake is an active tectonic rift such as Lake Baikal and, second, the lake is the result of glacial scouring. The distinct characteristics of an extensional rift can be easily identified with our aerogeophysical survey. The geological interpretation of the airborne geophysical survey will provide the first geological constraints of the interior of the East Antarctic continent based on modern data. In addition, the underlying geology will influence the ecosystem within the lake. \u003cbr/\u003e\u003cbr/\u003eOne of the critical issues for the ecosystem within the lake will be the flux of nutrients. A preliminary estimation of the regions of freezing and melting based on the distance between distinctive internal layers observed on the radar data will be made. These basic boundary conditions will provide guidance for a potential international effort aimed at in situ exploration of the lake and improve the understanding of East Antarctic geologic structures.", "east": 110.0, "geometry": "POINT(105.5 -77.25)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e MAGNETIC FIELD/ELECTRIC FIELD INSTRUMENTS \u003e MAGNETOMETERS \u003e MGF; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e AIRGRAV", "is_usap_dc": true, "keywords": "Gravity; GLACIERS/ICE SHEETS; East Antarctica; USAP-DC; Lake Vostok; Airborne Radar; Subglacial Lake; MAGNETIC FIELD; GRAVITY", "locations": "East Antarctica; Lake Vostok", "north": -75.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Bell, Robin; Studinger, Michael S.", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n", "uid": "p0010097", "west": 101.0}, {"awards": "9615704 Bell, Robin; 9615832 Blankenship, Donald", "bounds_geometry": "POLYGON((-180 -74,-176 -74,-172 -74,-168 -74,-164 -74,-160 -74,-156 -74,-152 -74,-148 -74,-144 -74,-140 -74,-140 -75.6,-140 -77.2,-140 -78.8,-140 -80.4,-140 -82,-140 -83.6,-140 -85.2,-140 -86.8,-140 -88.4,-140 -90,-144 -90,-148 -90,-152 -90,-156 -90,-160 -90,-164 -90,-168 -90,-172 -90,-176 -90,180 -90,174 -90,168 -90,162 -90,156 -90,150 -90,144 -90,138 -90,132 -90,126 -90,120 -90,120 -88.4,120 -86.8,120 -85.2,120 -83.6,120 -82,120 -80.4,120 -78.8,120 -77.2,120 -75.6,120 -74,126 -74,132 -74,138 -74,144 -74,150 -74,156 -74,162 -74,168 -74,174 -74,-180 -74))", "dataset_titles": "SOAR-PPT Airborne gravity data; SOAR-WLK Airborne gravity data", "datasets": [{"dataset_uid": "601293", "doi": "10.15784/601293", "keywords": "Aerogeophysics; Airborne Gravity; Airplane; Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Gravity Data; Potential Field; Solid Earth; Transantarctic Mountains", "people": "Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-WLK Airborne gravity data", "url": "https://www.usap-dc.org/view/dataset/601293"}, {"dataset_uid": "601292", "doi": "10.15784/601292", "keywords": "Aerogeophysics; Airborne Gravity; Airplane; Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Gravity Data; Potential Field; Solid Earth; Transantarctic Mountains", "people": "Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-PPT Airborne gravity data", "url": "https://www.usap-dc.org/view/dataset/601292"}], "date_created": "Fri, 24 Apr 2020 00:00:00 GMT", "description": "Continental extension produces a great variety of structures from the linear narrow rifts of the East African Rift to the diffuse extension of the Basin and Range Province of the Western U.S. Rift shoulder uplift varies dramatically between rift flanks. The cause of variable rift width and crustal thinning is fairly well explained by variable initial heat flow and crustal thickness. Mechanical stretching of the lithosphere has been linked to rift shoulder uplift but the cause of variable rift flank uplift remains poorly understood. The Transantarctic Mountains (TAM) are an extreme example of rift flank uplift, extending over 3500 km across Antarctica and reaching elevations up to 4500 m and thus constitute a unique feature of EarthOs crust. The range was formed in the extensional environment associated with the Mesozoic and Cenozoic breakup of Gondwanaland. Geological and geophysical work has shown that the TAM developed along the long-lived lithospheric boundary between East and West Antarctica reactivated by a complex history of extensional and translational microplate motions. The TAM are not uniform along strike. Along the OWilkes FrontO, the northern segment of the rift extends from North Victoria Land to Byrd Glacier. The Wilkes Front architecture consists of (1) thin, extended crust forming the Victoria Land Basin in the Ross Sea, (2) the TAM rift shoulder, and (3) a long-wavelength down- ward forming the Wilkes Basin. Contrasting structures are mapped along the OPensacola/PoleO Front, the southern segment of the rift extending from the Nimrod Glacier to the Pensacola Mountains. Along this southern section no rift basin has been mapped to date and the down-ward along the East Antarctic, or ObacksideO, edge of the mountains is less pronounced. A flexural model linking the extension in the Ross Sea to the formation of both the mountains and the Wilkes Basin has been considered as a me chanism for uplift of the entire mountain range. The variability in fundamental architecture along the TAM indicates that neither a single event nor a sequence of identical events produced the rift flank uplift. The observation of variable architecture suggests complex mechanisms and possibly a fundamental limitation in maximum sustainable rift flank elevation. The motivation for studying the TAM is to try to understand the geodynamics of this extreme elevation rift flank. Are the geodynamics of the area unique, or does the history of glaciation and related erosion contribute to the extreme uplift? With the existing data sets it is difficult to confidently constrain the geological architecture across representative sections of the TAM. Any effort to refine geodynamic mechanisms requires this basic understanding of the TAM architecture. The goal of this project is to (1) constrain the architecture of the rift system as well as the distribution and structure of sedimentary basins, glacial erosion and mafic igneous rocks surrounding the rift flank by acquiring three long wavelength geophysical transects with integrated gravity, magnetics, ice- penetrating radar, and ice surface measurements, (2) quantify the contribution of various geodynamic mechanisms to understand the geological conditions which can lead to extreme rift flank uplift, and (3) use the improved understanding of architecture and geophysical data to test geodynamic models in order to improve our understanding both of the TAM geodynamics and the general problem of the geodynamics of rift flank uplift worldwide. This project will allow development of a generalized framework for understanding the development of rift flank uplift as well as address the question of the specific geodynamic evolution of the TAM.", "east": -140.0, "geometry": "POINT(170 -82)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": true, "keywords": "USAP-DC; Transantarctic Mountains; GRAVITY FIELD; TECTONICS", "locations": "Transantarctic Mountains", "north": -74.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Bell, Robin; Buck, W. Roger; Blankenship, Donald D.", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Contrasting Architecture and Dynamics of the Transantarctic Mountains", "uid": "p0010095", "west": 120.0}, {"awards": "9319854 Bell, Robin; 9319877 Finn, Carol; 9319369 Blankenship, Donald", "bounds_geometry": "POLYGON((-155 -77.5,-150 -77.5,-145 -77.5,-140 -77.5,-135 -77.5,-130 -77.5,-125 -77.5,-120 -77.5,-115 -77.5,-110 -77.5,-105 -77.5,-105 -78.2,-105 -78.9,-105 -79.6,-105 -80.3,-105 -81,-105 -81.7,-105 -82.4,-105 -83.1,-105 -83.8,-105 -84.5,-110 -84.5,-115 -84.5,-120 -84.5,-125 -84.5,-130 -84.5,-135 -84.5,-140 -84.5,-145 -84.5,-150 -84.5,-155 -84.5,-155 -83.8,-155 -83.1,-155 -82.4,-155 -81.7,-155 -81,-155 -80.3,-155 -79.6,-155 -78.9,-155 -78.2,-155 -77.5))", "dataset_titles": "SOAR-BSB Airborne gravity data for the CASERTZ/WAIS project; SOAR-IRE airborne gravity data for the CASERTZ/WAIS project; SOAR-TKD airborne gravity data for the CASERTZ/WAIS project; SOAR-WAZ Airborne gravity data for the CASERTZ/WAIS project", "datasets": [{"dataset_uid": "601289", "doi": "10.15784/601289", "keywords": "Aerogeophysics; Airborne Gravity; Airplane; Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Gravity Data; Marie Byrd Land; Potential Field; Solid Earth; WAIS", "people": "Arko, Robert A.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-TKD airborne gravity data for the CASERTZ/WAIS project", "url": "https://www.usap-dc.org/view/dataset/601289"}, {"dataset_uid": "601288", "doi": "10.15784/601288", "keywords": "Aerogeophysics; Airborne Gravity; Airplane; Antarctica; Free Air Gravity; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Gravity Data; Marie Byrd Land; Solid Earth; WAIS", "people": "Arko, Robert A.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-BSB Airborne gravity data for the CASERTZ/WAIS project", "url": "https://www.usap-dc.org/view/dataset/601288"}, {"dataset_uid": "601290", "doi": "10.15784/601290", "keywords": "Aerogeophysics; Airborne Gravity; Airplane; Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Gravity Data; Marie Byrd Land; Potential Field; Solid Earth; WAIS", "people": "Arko, Robert A.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-IRE airborne gravity data for the CASERTZ/WAIS project", "url": "https://www.usap-dc.org/view/dataset/601290"}, {"dataset_uid": "601291", "doi": "10.15784/601291", "keywords": "Aerogeophysics; Airborne Gravity; Airplane; Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Gravity Data; Marie Byrd Land; Potential Field; Solid Earth; WAIS", "people": "Arko, Robert A.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-WAZ Airborne gravity data for the CASERTZ/WAIS project", "url": "https://www.usap-dc.org/view/dataset/601291"}], "date_created": "Fri, 24 Apr 2020 00:00:00 GMT", "description": "This award supports a project to conduct an integrated geophysical survey over a large portion of the West Antarctic Ice Sheet (WAIS) toward an understanding of the dynamic behavior of the ice sheet and the nature of the lithosphere beneath the ice sheet. West Antarctica is characterized by two kinds of the Earth s most dynamic systems, a continental rift (the West Antarctic Rift System) and a marine based ice sheet (the WAIS). Active continental rift systems, caused by divergent plate motions, result in thinned continental crust. Associated with the thin crust are fault-bounded sedimentary basins, active volcanism, and elevated heat flow. Marine ice sheets are characterized by rapidly moving streams of ice, penetrating and draining a slowly moving ice reservoir. Evidence left by past marine ice sheets indicates that they may have a strongly non- linear response to long-term climate change which results in massive and rapid discharges of ice. Understanding the evolution of the ice stream system and its interaction with the interior ice is the key to understanding this non-linear response. Subglacial geology and ice dynamics are generally studied in isolation, but evidence is mounting that the behavior of the West Antarctic ice streams may be closely linked to the nature of the underlying West Antarctic rift system. The fast moving ice streams appear to glide on a lubricating layer of water-saturated till. This till requires easily eroded sediment and a source of water, both of which may be controlled by the geology of the rift system; the sediments from the fault-bounded basins and the water from the elevated heat flux associated with active lithospheric extension. This project represents an interdisciplinary aerogeophysical study to characterize the lithosphere of the West Antarctic rift system beneath critical regions of the WAIS. The objective is to determine the effects of the rift architect ure, as manifested by the distribution of sedimentary basins and volcanic constructs, on the ice stream system. The research tool is a unique geophysical aircraft with laser altimetry, ice penetrating radar, aerogravity, and aeromagnetic systems integrated with a high precision kinematic GPS navigation system. It is capable of imaging both the surface and bed of the ice sheet while simultaneously measuring the gravity and magnetic signature of the subglacial lithosphere. Work to be done under this award will build on work already completed in the southern sector of central West Antarctica and it will focus on the region of the Byrd Subglacial Basin and Ice Stream D. The ice sheet in these regions is completely covered by satellite imagery and so this project will be integrated with remote sensing studies of the ice stream. The changing dynamics of Ice Stream D, as with other West Antarctic ice streams, seem to be correlated with changes in the morphological provinces of the underlying rift system. The experimental targets proceed from the divide of the interior ice, downstream through the onset of streaming to the trunk of Ice Stream D. This study will be coordinated with surface glaciological investigations of Ice Stream D and will be used to guide cooperative over-snow seismic investigations of the central West Antarctic rift system. The data will also be used to select a site for future deep ice coring along the crest of the WAIS. These data represent baseline data for long term global change monitoring work and represent crucial boundary conditions for ice sheet modeling efforts.", "east": -105.0, "geometry": "POINT(-130 -81)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": true, "keywords": "USAP-DC; MAGNETIC FIELD; GRAVITY FIELD; Antarctica; GLACIERS/ICE SHEETS; Marie Byrd Land; Airborne Gravity", "locations": "Marie Byrd Land; Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": null, "persons": "Bell, Robin; Blankenship, Donald D.; Finn, C. A.", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.5, "title": "Collaborative Research: Lithospheric Controls on the Behavior of the West Antarctic Ice Sheet: Corridor Aerogeophysics of Eastern Ross Transect Zone", "uid": "p0010094", "west": -155.0}, {"awards": "9615282 Siddoway, Christine; 9615281 Luyendyk, Bruce", "bounds_geometry": "POLYGON((-170 -76,-166.5 -76,-163 -76,-159.5 -76,-156 -76,-152.5 -76,-149 -76,-145.5 -76,-142 -76,-138.5 -76,-135 -76,-135 -76.8,-135 -77.6,-135 -78.4,-135 -79.2,-135 -80,-135 -80.8,-135 -81.6,-135 -82.4,-135 -83.2,-135 -84,-138.5 -84,-142 -84,-145.5 -84,-149 -84,-152.5 -84,-156 -84,-159.5 -84,-163 -84,-166.5 -84,-170 -84,-170 -83.2,-170 -82.4,-170 -81.6,-170 -80.8,-170 -80,-170 -79.2,-170 -78.4,-170 -77.6,-170 -76.8,-170 -76))", "dataset_titles": "Bedrock sample data, Ford Ranges region (Marie Byrd Land); SOAR-WMB Airborne gravity data", "datasets": [{"dataset_uid": "601294", "doi": "10.15784/601294", "keywords": "Aerogeophysics; Airborne Gravity; Airplane; Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Gravity Data; Marie Byrd Land; Potential Field; Ross Sea; Solid Earth", "people": "Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-WMB Airborne gravity data", "url": "https://www.usap-dc.org/view/dataset/601294"}, {"dataset_uid": "601829", "doi": "10.15784/601829", "keywords": "Antarctica; Cryosphere; Gondwana; Marie Byrd Land; Migmatite", "people": "Siddoway, Christine", "repository": "USAP-DC", "science_program": null, "title": "Bedrock sample data, Ford Ranges region (Marie Byrd Land)", "url": "https://www.usap-dc.org/view/dataset/601829"}], "date_created": "Fri, 24 Apr 2020 00:00:00 GMT", "description": "This award supports a collaborative project that combines air and ground geological-geophysical investigations to understand the tectonic and geological development of the boundary between the Ross Sea Rift and the Marie Byrd Land (MBL) volcanic province. The project will determine the Cenozoic tectonic history of the region and whether Neogene structures that localized outlet glacier flow developed within the context of Cenozoic rifting on the eastern Ross Embayment margin, or within the volcanic province in MBL. The geological structure at the boundary between the Ross Embayment and western MBL may be a result of: 1) Cenozoic extension on the eastern shoulder of the Ross Sea rift; 2) uplift and crustal extension related to Neogene mantle plume activity in western MBL; or a combination of the two. Faulting and volcanism, mountain uplift, and glacier downcutting appear to now be active in western MBL, where generally East-to-West-flowing outlet glaciers incise Paleozoic and Mesozoic bedrock, and deglaciated summits indicate a previous North-South glacial flow direction. This study requires data collection using SOAR (Support Office for Aerogeophysical Research, a facility supported by Office of Polar Programs which utilizes high precision differential GPS to support a laser altimeter, ice-penetrating radar, a towed proton magnetometer, and a Bell BGM-3 gravimeter). This survey requires data for 37,000 square kilometers using 5.3 kilometer line spacing with 15.6 kilometer tie lines, and 86,000 square kilometers using a grid of 10.6 by 10.6 kilometer spacing. Data will be acquired over several key features in the region including, among other, the eastern edge of the Ross Sea rift, over ice stream OEO, the transition from the Edward VII Peninsula plateau to the Ford Ranges, the continuation to the east of a gravity high known from previous reconnaissance mapping over the Fosdick Metamorphic Complex, an d the extent of the high-amplitude magnetic anomalies (volcanic centers?) detected southeast of the northern Ford Ranges by other investigators. SOAR products will include glaciology data useful for studying driving stresses, glacial flow and mass balance in the West Antarctic Ice Sheet (WAIS). The ground program is centered on the southern Ford Ranges. Geologic field mapping will focus on small scale brittle structures for regional kinematic interpretation, on glaciated surfaces and deposits, and on datable volcanic rocks for geochronologic control. The relative significance of fault and joint sets, the timing relationships between them, and the probable context of their formation will also be determined. Exposure ages will be determined for erosion surfaces and moraines. Interpretation of potential field data will be aided by on ground sampling for magnetic properties and density as well as ground based gravity measurements. Oriented samples will be taken for paleomagnetic studies. Combined airborne and ground investigations will obtain basic data for describing the geology and structure at the eastern boundary of the Ross Embayment both in outcrop and ice covered areas, and may be used to distinguish between Ross Sea rift- related structural activity from uplift and faulting on the perimeter of the MBL dome and volcanic province. Outcrop geology and structure will be extrapolated with the aerogeophysical data to infer the geology that resides beneath the WAIS. The new knowledge of Neogene tectonics in western MBL will contribute to a comprehensive model for the Cenozoic Ross rift and to understanding of the extent of plume activity in MBL. Both are important for determining the influence of Neogene tectonics on the ice streams and WAIS.", "east": -135.0, "geometry": "POINT(-152.5 -80)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e LGS", "is_usap_dc": true, "keywords": "GRAVITY; USAP-DC; Ross Sea; TECTONICS; Marie Byrd Land", "locations": "Ross Sea; Marie Byrd Land", "north": -76.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Luyendyk, Bruce P.; Siddoway, Christine", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.0, "title": "Air-Ground Study of Tectonics at the Boundary Between the Eastern Ross Embayment and Western Marie Byrd Land, Antarctica: Basement Geology and Structure", "uid": "p0010096", "west": -170.0}, {"awards": "1142158 Cheng, Chi-Hing; 0231006 DeVries, Arthur", "bounds_geometry": "POLYGON((163 -76.5,163.5 -76.5,164 -76.5,164.5 -76.5,165 -76.5,165.5 -76.5,166 -76.5,166.5 -76.5,167 -76.5,167.5 -76.5,168 -76.5,168 -76.63,168 -76.76,168 -76.89,168 -77.02,168 -77.15,168 -77.28,168 -77.41,168 -77.54,168 -77.67,168 -77.8,167.5 -77.8,167 -77.8,166.5 -77.8,166 -77.8,165.5 -77.8,165 -77.8,164.5 -77.8,164 -77.8,163.5 -77.8,163 -77.8,163 -77.67,163 -77.54,163 -77.41,163 -77.28,163 -77.15,163 -77.02,163 -76.89,163 -76.76,163 -76.63,163 -76.5))", "dataset_titles": "High-resolution benthic seawater temperature record 1999-2012 (25-40m depth) from near intake jetty at McMurdo Station, Antarctica; Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae)", "datasets": [{"dataset_uid": "601811", "doi": null, "keywords": "Antarctica; Bellingshausen Sea; Cryosphere; Southern Ocean", "people": "Desvignes, Thomas; McDowell, Jan; Cheng, Chi-Hing; Biesack, Ellen; Steinberg, Deborah; Hilton, Eric; Corso, Andrew", "repository": "USAP-DC", "science_program": "LTER", "title": "Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae)", "url": "https://www.usap-dc.org/view/dataset/601811"}, {"dataset_uid": "601275", "doi": null, "keywords": "Antarctica; Benthic; McMurdo Sound; Mcmurdo Station; Oceans; Physical Oceanography; Temperature Probe; Water Temperature", "people": "Cheng, Chi-Hing; Devries, Arthur; Cziko, Paul", "repository": "USAP-DC", "science_program": null, "title": "High-resolution benthic seawater temperature record 1999-2012 (25-40m depth) from near intake jetty at McMurdo Station, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601275"}], "date_created": "Wed, 08 Apr 2020 00:00:00 GMT", "description": "Antarctic notothenioid fishes exhibit two adaptive traits to survive in frigid temperatures. The first of these is the production of anti-freeze proteins in their blood and tissues. The second is a system-wide ability to perform cellular and physiological functions at extremely cold temperatures.The proposal goals are to show how Antarctic fishes use these characteristics to avoid freezing, and which additional genes are turned on, or suppressed in order for these fishes to maintain normal physiological function in extreme cold temperatures. Progressively colder habitats are encountered in the high latitude McMurdo Sound and Ross Shelf region, along with somewhat milder near?shore water environments in the Western Antarctic Peninsula (WAP). By quantifying the extent of ice crystals invading and lodging in the spleen, the percentage of McMurdo Sound fish during austral summer (Oct-Feb) will be compared to the WAP intertidal fish during austral winter (Jul-Sep) to demonstrate their capability and extent of freeze avoidance. Resistance to ice entry in surface epithelia (e.g. skin, gill and intestinal lining) is another expression of the adaptation of these fish to otherwise lethally freezing conditions.\u003cbr/\u003e\u003cbr/\u003eThe adaptive nature of a uniquely characteristic polar genome will be explored by the study of the transcriptome (the set of expressed RNA transcripts that constitutes the precursor to set of proteins expressed by an entire genome). Three notothenioid species (E.maclovinus, D. Mawsoni and C. aceratus) will be analysed to document evolutionary genetic changes (both gain and loss) shaped by life under extreme chronic cold. A differential gene expression (DGE) study will be carried out on these different species to evaluate evolutionary modification of tissue-wide response to heat challenges. The transcriptomes and other sequencing libraries will contribute to de novo ice-fish genome sequencing efforts.", "east": 168.0, "geometry": "POINT(165.5 -77.15)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD", "is_usap_dc": true, "keywords": "McMurdo Sound; MARINE ECOSYSTEMS; Water Temperature; AQUATIC SCIENCES; OCEAN TEMPERATURE; FIELD INVESTIGATION; USAP-DC", "locations": "McMurdo Sound", "north": -76.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Cheng, Chi-Hing; Devries, Arthur", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.8, "title": "Antarctic Notothenioid Fish Freeze Avoidance and Genome-wide Evolution for Life in the Cold", "uid": "p0010091", "west": 163.0}, {"awards": "1840058 Jenouvrier, Stephanie", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Causes and consequences of pair-bond disruption in a sex-skewed population of a long-lived monogamous seabird: the wandering Albatross; Demographic outputs and their variances for three life history complexes for the Southern Fulmar across contrasted sea ice conditions.; Impact of Climate Change on Pair-Bond Dynamics of Snow Petrels (Pagodroma nivea); Supplementary material from \"Boldness predicts divorce rates in wandering albatrosses", "datasets": [{"dataset_uid": "200372", "doi": "https://rs.figshare.com/collections/Supplementary_material_from_Boldness_predicts_divorce_rates_in_wandering_albatrosses_i_Diomedea_exulans_i_/6181063", "keywords": null, "people": null, "repository": "https://rs.figshare.com/", "science_program": null, "title": "Supplementary material from \"Boldness predicts divorce rates in wandering albatrosses", "url": "https://rs.figshare.com/collections/Supplementary_material_from_Boldness_predicts_divorce_rates_in_wandering_albatrosses_i_Diomedea_exulans_i_/6181063"}, {"dataset_uid": "601585", "doi": "10.15784/601585", "keywords": "Antarctica; Biota; Birds; East Antarctica; Southern Fulmar", "people": "Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Demographic outputs and their variances for three life history complexes for the Southern Fulmar across contrasted sea ice conditions.", "url": "https://www.usap-dc.org/view/dataset/601585"}, {"dataset_uid": "601518", "doi": "10.15784/601518", "keywords": "Antarctica; Biota; Wandering Albatross", "people": "Barbraud, Christophe; Jenouvrier, Stephanie; Sun, Ruijiao; Delord, Karine", "repository": "USAP-DC", "science_program": null, "title": "Causes and consequences of pair-bond disruption in a sex-skewed population of a long-lived monogamous seabird: the wandering Albatross", "url": "https://www.usap-dc.org/view/dataset/601518"}, {"dataset_uid": "601832", "doi": "10.15784/601832", "keywords": "Antarctica; Climate Change; Cryosphere; Ile des Petrels, Pointe Geologie Archipelago (66\u25e640\u2032 S, 140\u25e601\u2032 106 E), Terre Adelie, Antarctica.", "people": "jenouvrier, stephanie", "repository": "USAP-DC", "science_program": null, "title": "Impact of Climate Change on Pair-Bond Dynamics of Snow Petrels (Pagodroma nivea)", "url": "https://www.usap-dc.org/view/dataset/601832"}], "date_created": "Wed, 01 Apr 2020 00:00:00 GMT", "description": "The goal of this project is to understand the drivers of pair disruption and quantify its resulting effects on individual fitness components and population growth rate and structure for two procellariiformes breeding in the Southern Ocean: the wandering albatross and the snow petrel, which both form long-lasting pair bonds. The mechanisms of pair disruption may be contrasted between these species, as pair disruption in wandering albatross may occur with the death of a partner by incidental by-catch in fisheries, while in snow petrels it may occur through divorce and climate-related conditions. Unique long-term individual mark-recapture data sets exist for these iconic polar species, allowing for a comprehensive study of the rates, causes and consequences of pair disruption and how they differ among species.\r\n\r\nThis study will result in the most detailed analysis to date of the impact of social monogamy and long-term pair bonds on individual fitness components (vital rates: survival, recruitment and fecundity; life-history outcomes: life expectancy, age at 1st breeding and lifetime reproductive success; and occupancy times: duration of pair bond or widowhood) and population growth and structure (e.g, sex ratio of individuals available for mating). Specifically, the investigators will assess:\r\n1. Variations in pair disruption rates, and if they are related to global change (by-catch in the case of albatross widowing, and climate in the case of petrel divorce) by developing a state-of-the-art statistical multievent mark-recapture model. \r\n2. Impacts of pair disruption on vital rates, specifically whether i) greater familiarity and better coordination within pairs improves breeding performance and survival, ii) mating costs reduce the probability of breeding and iii) divorce is more likely to occur after a breeding failure. \r\n3. Impacts of pair disruption on life-history outcomes and occupancy times using Markov chain stochastic life cycle models. \r\n4. Impacts of pair disruption on population dynamics by developing a novel non-linear two-sex matrix population model. \r\nThe investigators will develop novel sensitivity and Life Table Response Experiment analyses to examine the respective effects of fisheries, climate, vital rates, and pair-disruption rates on life-history outcomes, occupancy times, and population growth and structure, and their variations among year and species. \r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e VISUAL OBSERVATIONS", "is_usap_dc": true, "keywords": "ECOLOGICAL DYNAMICS; FIELD INVESTIGATION; East Antarctica; USAP-DC", "locations": "East Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Jenouvrier, Stephanie", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "https://rs.figshare.com/", "repositories": "https://rs.figshare.com/; USAP-DC", "science_programs": null, "south": -90.0, "title": "Polar Seabirds with Long-term Pair Bonds: Effects of Mating on Individual Fitness and Population Dynamics", "uid": "p0010090", "west": -180.0}, {"awards": "1643733 Trusel, Luke; 1643715 Moussavi, Mahsa Sadat", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Supraglacial Lakes in Antarctica", "datasets": [{"dataset_uid": "601401", "doi": "10.15784/601401", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Landsat-8; Satellite Imagery; Supraglacial Lake", "people": "Trusel, Luke; Halberstadt, Anna Ruth; Moussavi, Mahsa; Abdalati, Waleed; Pope, Allen", "repository": "USAP-DC", "science_program": null, "title": "Supraglacial Lakes in Antarctica", "url": "https://www.usap-dc.org/view/dataset/601401"}], "date_created": "Mon, 16 Mar 2020 00:00:00 GMT", "description": "Melting of snow and ice at the surface of the Antarctic ice sheet can lead to the formation of meltwater lakes, an important precursor to ice-shelf collapse and accelerated ice-sheet mass loss. Understanding the present state of Antarctic surface melt provides a baseline to gauge how quickly melt impacts could evolve in the future and to reduce uncertainties in estimates of future sea-level rise. This project will use a suite of complimentary measurements from Earth-observing satellites, ground observations, and numerical climate and ice-shelf models to enhance understanding of surface melt and lakes, as well as the processes linking these systems. The project directly supports the scientific training of a postdoctoral associate and several undergraduate researchers. In addition, it will promote public scientific literacy and the broadening of quantitative skills for high-school students through the development and implementation of an educational unit in a partnership with an education and outreach expert and two high school teachers.\u003cbr/\u003e\u003cbr/\u003eAccurate prediction of sea-level contributions from Antarctica critically requires understanding current melting and supraglacial lake conditions. This project will quantify Antarctic surface melt and supraglacial lakes, and the linkages between the two phenomena. Scatterometer data will enable generation of a 19-year multi-sensor melt time series. Synthetic aperture radar data will document melt conditions across all Antarctic ice shelves at the highest spatial resolution to date (40 m). Multispectral satellite imagery will be used to delineate and measure the depth of supraglacial lakes--for the first time studying the spatial and temporal variations of Antarctic supraglacial lakes. Melt and lake observations will be compared to identify agreement and disagreement. Melt observations will be used to evaluate biases in a widely used, reanalysis-driven, regional climate model. This model will then be used to examine climatic and glaciological variables associated with supraglacial lakes. Finally, in situ observations and climate model output will drive a numerical model that simulates the entire lifecycle of surface melt and possible subsequent lake formation.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; Supraglacial Lake; ICE SHEETS; Satellite Imagery; LANDSAT; Antarctica; USAP-DC; AMD; USA/NSF; SENTINEL-2A", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Moussavi, Mahsa; Pope, Allen; Trusel, Luke", "platforms": "SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e LANDSAT \u003e LANDSAT; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SENTINEL-2 \u003e SENTINEL-2A", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Water on the Antarctic Ice Sheet: Quantifying Surface Melt and Mapping Supraglacial Lakes", "uid": "p0010088", "west": -180.0}, {"awards": "1743035 Saba, Grace", "bounds_geometry": "POLYGON((164 -72.2,165 -72.2,166 -72.2,167 -72.2,168 -72.2,169 -72.2,170 -72.2,171 -72.2,172 -72.2,173 -72.2,174 -72.2,174 -72.74,174 -73.28,174 -73.82,174 -74.36,174 -74.9,174 -75.44,174 -75.98,174 -76.52,174 -77.06,174 -77.6,173 -77.6,172 -77.6,171 -77.6,170 -77.6,169 -77.6,168 -77.6,167 -77.6,166 -77.6,165 -77.6,164 -77.6,164 -77.06,164 -76.52,164 -75.98,164 -75.44,164 -74.9,164 -74.36,164 -73.82,164 -73.28,164 -72.74,164 -72.2))", "dataset_titles": "Grazing rates of Euphausia crystallorophias from RVIB Nathaniel B. Palmer NBP1801 in the Ross Sea, Jan.-Feb. 2018; NBP1801 Expedition data; ru32-20180109T0531; Zooplankton abundance from Isaacs-Kid Midwater Trawl (IKMT) hauls from RVIB Nathaniel B. Palmer NBP1801 in the Ross Sea, Jan.-Feb. 2018; Zooplankton abundance from ring net tows from RVIB Nathaniel B. Palmer NBP1801 in the Ross Sea, January 2018", "datasets": [{"dataset_uid": "200139", "doi": "10.1575/1912/bco-dmo.792478.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Grazing rates of Euphausia crystallorophias from RVIB Nathaniel B. Palmer NBP1801 in the Ross Sea, Jan.-Feb. 2018", "url": "https://www.bco-dmo.org/dataset/792478"}, {"dataset_uid": "200056", "doi": "10.7284/907753", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1801 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1801"}, {"dataset_uid": "200138", "doi": "10.1575/1912/bco-dmo.792385.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Zooplankton abundance from Isaacs-Kid Midwater Trawl (IKMT) hauls from RVIB Nathaniel B. Palmer NBP1801 in the Ross Sea, Jan.-Feb. 2018", "url": "https://www.bco-dmo.org/dataset/792385"}, {"dataset_uid": "200137", "doi": "10.1575/1912/bco-dmo.789299.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Zooplankton abundance from ring net tows from RVIB Nathaniel B. Palmer NBP1801 in the Ross Sea, January 2018", "url": "https://www.bco-dmo.org/dataset/789299"}, {"dataset_uid": "200140", "doi": "", "keywords": null, "people": null, "repository": "ERDDAP", "science_program": null, "title": "ru32-20180109T0531", "url": "http://slocum-data.marine.rutgers.edu/erddap/tabledap/ru32-20180109T0531-profile-sci-delayed.html"}], "date_created": "Thu, 27 Feb 2020 00:00:00 GMT", "description": "Terra Nova Bay (western Ross Sea, Antarctica) supports dense populations of several key species in the Ross Sea food web, including copepods, crystal krill (Euphausia crystallorophias), Antarctic silverfish (Pleuragramma antarcticum), and colonies of Ad\u00e9lie and Emperor penguins that feed primarily on crystal krill and silverfish. Absent from our understanding of the Ross Sea food web is zooplankton and silverfish mesoscale distribution, spatial structure of age/maturity classes, and their interactions with physical drivers and each other. The quantitative linkages between primary producers and the higher trophic levels, specifically, the processes responsible for the regulation of abundance and rates of middle trophic levels dominated by copepods and crystal krill (Euphausia crystallorophias), is virtually unknown. Given that the next century will see extensive changes in the Ross Sea\u2019s ice distributions and oceanography as a result of climate change, understanding the basic controls of zooplankton and silverfish abundance and distribution is essential. \r\nDuring a January \u2013 March 2018 cruise in the western Ross Sea, we deployed a glider equipped with an echo sounder (Acoustic Zooplankton Fish Profiler) that simultaneously measured depth, temperature, conductivity, chlorophyll fluorescence, and dissolved oxygen. Additionally, net tows, mid-water trawls, and crystal krill grazing experiments were conducted. Our study provided the first glider-based acoustic assessment of simultaneous distributions of multiple trophic levels in the Ross Sea, from which predator-prey interactions and the relationships between organisms and physics drivers (sea ice, circulation features) were investigated. We illustrated high variability in ocean physics, phytoplankton biomass, and crystal krill biomass and aggregation over time and between locations within Terra Nova Bay. Biomass of krill was highest in locations characterized by deeper mixed layers and highest integrated chlorophyll concentrations. Krill aggregations were consistently located at depth well below the mixed layer and chlorophyll maximum. Experiments investigating krill grazing, in combination with krill depth distributions relative to chlorophyll biomass, illuminate high krill grazing rates could be attributed to the occupation of a unique niche whereby they are opportunistically feeding on sinking high concentrations of detritus derived from surface blooms. The information on the abundance, distribution, and interactions of key species in multiple trophic levels resulting from this project provide a conceptual background to understand how this ecosystem might respond to future conditions under climate change.\r\nOur project tested the capability of a multi-frequency echo sounder on a glider for the first time. The production of consistent, vertically-resolved, high resolution glider-based acoustic measurements will pave the way for cost-effective, automated examination of entire food webs and ecosystems in regions all over the global ocean. A wide range of users including academic and government scientists, ecosystem-based fisheries managers, and monitoring programs including those conducted by OOI, IOOS, and NOAA will benefit from this project. This project also provided the opportunity to focus on broadening participation in research and articulating the societal benefits through education and innovative outreach programs. A data set from this project is being included in the new NSF-funded Polar CAP initiative, that will be used by a diverse and young audience to increase understanding of the polar system and the ability to reason with data. Finally, this project provided a unique field opportunity and excellent hand-on training for a post-doctoral researcher, a graduate student, and two undergraduate students.", "east": 174.0, "geometry": "POINT(169 -74.9)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; FISH; Terra Nova Bay; AQUATIC SCIENCES; PELAGIC; PLANKTON; USAP-DC; ANIMALS/VERTEBRATES", "locations": "Terra Nova Bay", "north": -72.2, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Saba, Grace", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO; ERDDAP; R2R", "science_programs": null, "south": -77.6, "title": "Using Bio-acoustics on an Autonomous Surveying Platform for the Examination of Phytoplankton-zooplankton and Fish Interactions in the Western Ross Sea", "uid": "p0010086", "west": 164.0}, {"awards": "1644027 Wallace, Paul; 1644013 Gaetani, Glenn; 1644020 Sims, Kenneth W.", "bounds_geometry": "POLYGON((164.1 -77.1,164.65 -77.1,165.2 -77.1,165.75 -77.1,166.3 -77.1,166.85 -77.1,167.4 -77.1,167.95 -77.1,168.5 -77.1,169.05 -77.1,169.6 -77.1,169.6 -77.235,169.6 -77.37,169.6 -77.505,169.6 -77.64,169.6 -77.775,169.6 -77.91,169.6 -78.045,169.6 -78.18,169.6 -78.315,169.6 -78.45,169.05 -78.45,168.5 -78.45,167.95 -78.45,167.4 -78.45,166.85 -78.45,166.3 -78.45,165.75 -78.45,165.2 -78.45,164.65 -78.45,164.1 -78.45,164.1 -78.315,164.1 -78.18,164.1 -78.045,164.1 -77.91,164.1 -77.775,164.1 -77.64,164.1 -77.505,164.1 -77.37,164.1 -77.235,164.1 -77.1))", "dataset_titles": "G170 Electron Microprobe Analyses of Melt Inclusions and Host Olivines; G170 Raman Spectroscopy \u0026 Tomography Volumes of Melt Inclusions and Vapor Bubbles; G170 Sample Locations Ross Island \u0026 Discovery Province; G170 Secondary Ion Mass Spectrometry Analses of Melt Inclusion Volatiles; G170 Secondary Ion Mass Spectrometry Analyses of Melt Inclusion Hydrogen Isotopes; Location and Description of Tephra Samples from the Erebus and Discovery Sub-provinces", "datasets": [{"dataset_uid": "601505", "doi": "10.15784/601505", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Electron Microprobe Analyses; Olivine; Petrography; Ross Island", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Electron Microprobe Analyses of Melt Inclusions and Host Olivines", "url": "https://www.usap-dc.org/view/dataset/601505"}, {"dataset_uid": "601504", "doi": "10.15784/601504", "keywords": "Antarctica; Ross Island; Sample/collection Description; Sample/Collection Description; Sample Location", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Sample Locations Ross Island \u0026 Discovery Province", "url": "https://www.usap-dc.org/view/dataset/601504"}, {"dataset_uid": "601507", "doi": "10.15784/601507", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Hydrogen; Ion Mass Spectrometry; Ross Island", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Secondary Ion Mass Spectrometry Analyses of Melt Inclusion Hydrogen Isotopes", "url": "https://www.usap-dc.org/view/dataset/601507"}, {"dataset_uid": "601506", "doi": "10.15784/601506", "keywords": "Antarctica; Ion Mass Spectrometry; Ross Island; Volatiles", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Secondary Ion Mass Spectrometry Analses of Melt Inclusion Volatiles", "url": "https://www.usap-dc.org/view/dataset/601506"}, {"dataset_uid": "601250", "doi": "10.15784/601250", "keywords": "Antarctica; Hut Point Peninsula; Mt. Bird; Mt. Morning; Mt. Terror; Ross Island; Turks Head; Turtle Rock", "people": "Gaetani, Glenn; Pamukcu, Ayla", "repository": "USAP-DC", "science_program": null, "title": "Location and Description of Tephra Samples from the Erebus and Discovery Sub-provinces", "url": "https://www.usap-dc.org/view/dataset/601250"}, {"dataset_uid": "601508", "doi": "10.15784/601508", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Melt Inclusions; Raman Spectroscopy; Ross Island; Vapor Bubbles; Volcanic", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Raman Spectroscopy \u0026 Tomography Volumes of Melt Inclusions and Vapor Bubbles", "url": "https://www.usap-dc.org/view/dataset/601508"}], "date_created": "Sat, 08 Feb 2020 00:00:00 GMT", "description": "The depths at which magmas are stored, their pre-eruptive volatile contents, and the rates at which they ascend to the Earth\u0027s surface are important controls on the dynamics of volcanic eruptions. Basaltic magmas are likely to be vapor undersaturated as they begin their ascent from the mantle through the crust, but volatile solubility drops with decreasing pressure. Once vapor saturation is achieved and the magma begins to degas, its pre-eruptive volatile content is determined largely by the depth at which it resides within the crust. Magma stored in deeper reservoirs tend to experience less pre-eruptive degassing and to be richer in volatiles than magma shallower reservoirs. Eruptive style is influenced by the rate at which a magma ascends from the reservoir to the surface through its effect on the efficiency of vapor bubble nucleation, growth, and coalescence. The proposed work will advance our understanding of pre-eruptive storage conditions and syn-eruptive ascent rates through a combined field and analytical research program. Volatile measurements from olivine-hosted melt inclusions will be used to systematically investigate magma storage depths and ascent rates associated with alkaline volcanism in the Erebus volcanic province. A central goal of the project is to provide a spatial and temporal framework for interpreting results from studies of present-day volcanic processes at Mt Erebus volcano. The Erebus volcanic province of Antarctica is especially well suited to this type of investigation because: (1) there are many exposed mafic scoria cones, fissure vents, and hyaloclastites (exposed in sea cliffs) that produced rapidly quenched, olivine-rich tephra; (2) existing volatile data for Ross Island MIs show that magma storage was relatively deep compared to many mafic volcanic systems; (3) some of the eruptive centers ejected mantle xenoliths, allowing for comparison of ascent rates for xenolith-bearing and xenolith-free eruptions, and comparison of ascent rates for those bearing xenoliths with times estimated from settling velocities; and (4) the cold, dry conditions in Antarctica result in excellent tephra preservation compared to tropical and even many temperate localities. The project provides new tools for assessing volcanic hazards, facilitates collaboration involving researchers from three different institutions (WHOI, U Wyoming, and U Oregon), supports the researchers\u0027 involvement in teaching, advising, and outreach, and provides an educational opportunity for a promising young postdoctoral researcher. Understanding the interrelationships among magma volatile contents, reservoir depths, and ascent rates is vital for assessing volcanic hazards associated with alkaline volcanism across the globe.\r\n\r\n", "east": 169.6, "geometry": "POINT(166.85 -77.775)", "instruments": null, "is_usap_dc": true, "keywords": "Tephra; Turtle Rock; USA/NSF; Amd/Us; LABORATORY; AMD; Ross Island; Turks Head; Hut Point Peninsula; LAVA SPEED/FLOW; USAP-DC; Mt. Morning; Mt. Terror; ROCKS/MINERALS/CRYSTALS; Mt. Bird; FIELD INVESTIGATION", "locations": "Ross Island; Mt. Morning; Mt. Bird; Mt. Terror; Hut Point Peninsula; Turtle Rock; Turks Head", "north": -77.1, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Gaetani, Glenn; Le Roux, Veronique; Sims, Kenneth; Wallace, Paul", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.45, "title": "Collaborative Research: Determining Magma Storage Depths and Ascent Rates for the Erebus Volcanic Province, Antarctica Using Diffusive Water Loss from Olivine-hosted Melt Inclusion", "uid": "p0010081", "west": 164.1}, {"awards": "1443268 Beard, Brian; 1443437 Carlson, Anders", "bounds_geometry": "POLYGON((-80 -65,-79 -65,-78 -65,-77 -65,-76 -65,-75 -65,-74 -65,-73 -65,-72 -65,-71 -65,-70 -65,-70 -65.5,-70 -66,-70 -66.5,-70 -67,-70 -67.5,-70 -68,-70 -68.5,-70 -69,-70 -69.5,-70 -70,-71 -70,-72 -70,-73 -70,-74 -70,-75 -70,-76 -70,-77 -70,-78 -70,-79 -70,-80 -70,-80 -69.5,-80 -69,-80 -68.5,-80 -68,-80 -67.5,-80 -67,-80 -66.5,-80 -66,-80 -65.5,-80 -65))", "dataset_titles": "Radiogenic isotopes of ODP Site 178-1096; Sand content of ODP Site 178-1096", "datasets": [{"dataset_uid": "200109", "doi": " doi:10.1594/PANGAEA.909411", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Sand content of ODP Site 178-1096", "url": "https://doi.pangaea.de/10.1594/PANGAEA.909411 "}, {"dataset_uid": "200108", "doi": " doi:10.1594/PANGAEA.909407 ", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Radiogenic isotopes of ODP Site 178-1096", "url": "https://doi.pangaea.de/10.1594/PANGAEA.909407"}], "date_created": "Fri, 31 Jan 2020 00:00:00 GMT", "description": "This project developed sediment provenance proxies to trace the sources of sediment discharged by the WAIS to the continental rise. The WAIS erodes sediments from various West Antarctic geologic terranes that are deposited in adjacent drift sites. The geochemistry and magnetic properties of drift sediments reflect the tectono-metamorphic history of their source terranes. Deglaciation of a terrane during WAIS collapse should be detectable by the loss of the terrane\u2019s geochemical and magnetic signature in continental-rise detrital sediments. Continental shelf late-Holocene sediments from near the current WAIS groundling line were analyzed for silt- and claysize Sr-Nd-Pb isotopes and major-trace elements. The suite of cores spans from the eastern Ross Sea to the northern tip of the Antarctic Peninsula and established the provenance signatures of the Ross and Amundsen Provinces of Marie Byrd Land, Pine Island Bay, Thurston Island/Eight Coast Block, Ellsworth-Whitmore Crustal Block, and Antarctic Peninsula terranes. Many of these terranes have similar tectono-metamorphic histories but Sr-Nd isotope data from detrital sediments suggest at least 3 distinct provenance signatures. This comprehensive grain-size-specific provenance data adds to on-going collection of glacial till mineral and bulk provenance data. An initial down core study of Ocean Drilling Program Site 1096 in the Bellingshausen Sea was used to assess the utility of these new grain-size-specific provenance proxies in documenting WAIS collapse. We found the presence of both the WAIS and APIS over the last 115,000 years, but absence of the WAIS before 115,000 years ago. This means that the WAIS was gone during the last interglacial period, an interval when sea level was at least 6 meters above present. ", "east": -70.0, "geometry": "POINT(-75 -67.5)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "West Antarctic Ice Sheet; GLACIERS/ICE SHEETS; West Antarctica; PALEOCLIMATE RECONSTRUCTIONS; NOT APPLICABLE; USAP-DC; ISOTOPES; GEOCHEMISTRY; Bellingshausen Sea", "locations": "West Antarctic Ice Sheet; West Antarctica; Bellingshausen Sea", "north": -65.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Anders, Carlson; Beard, Brian; Stoner, Joseph", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "PANGAEA", "repositories": "PANGAEA", "science_programs": null, "south": -70.0, "title": "Collaborative Research: Development of a Suite of Proxies to Detect Past Collapse of the West Antarctic Ice Sheet", "uid": "p0010079", "west": -80.0}, {"awards": "1842064 Tinto, Kirsteen", "bounds_geometry": "POLYGON((-115 -74,-113.9 -74,-112.8 -74,-111.7 -74,-110.6 -74,-109.5 -74,-108.4 -74,-107.3 -74,-106.2 -74,-105.1 -74,-104 -74,-104 -74.2,-104 -74.4,-104 -74.6,-104 -74.8,-104 -75,-104 -75.2,-104 -75.4,-104 -75.6,-104 -75.8,-104 -76,-105.1 -76,-106.2 -76,-107.3 -76,-108.4 -76,-109.5 -76,-110.6 -76,-111.7 -76,-112.8 -76,-113.9 -76,-115 -76,-115 -75.8,-115 -75.6,-115 -75.4,-115 -75.2,-115 -75,-115 -74.8,-115 -74.6,-115 -74.4,-115 -74.2,-115 -74))", "dataset_titles": "Gravity-derived bathymetry for the Thwaites, Crosson and Dotson ice shelves (2009-2019); Processed line aerogravity data over the Thwaites Glacier region (2018/19 season)", "datasets": [{"dataset_uid": "200159", "doi": "10.5285/b9b28a35-8620-4182-bf9c-638800b6679b", "keywords": null, "people": null, "repository": "UK PDC", "science_program": null, "title": "Processed line aerogravity data over the Thwaites Glacier region (2018/19 season)", "url": "https://data.bas.ac.uk/metadata.php?id=GB/NERC/BAS/PDC/01241"}, {"dataset_uid": "200160", "doi": "10.5285/7803de8b-8a74-466b-888e-e8c737bf21ce", "keywords": null, "people": null, "repository": "UK PDC", "science_program": null, "title": "Gravity-derived bathymetry for the Thwaites, Crosson and Dotson ice shelves (2009-2019)", "url": "https://data.bas.ac.uk/metadata.php?id=GB/NERC/BAS/PDC/01332"}], "date_created": "Wed, 08 Jan 2020 00:00:00 GMT", "description": "Considerable uncertainty remains in projections of future ice loss from West Antarctica. A recent decadal style U.S. National Academy of Sciences, Engineering, and Medicine report entitled: A Strategic Vision for NSF Investments in Antarctic and Southern Ocean Research (2015) identifies changing ice in Antarctica as one of the highest priority science problems facing communities around the globe. The report identifies Thwaites Glacier as a target for collaborative intense research efforts in the coming years. This project contributes to that effort by deploying an instrument on board airborne surveys that will help to constrain the unknown terrains beneath the Thwaites Ice Shelf and in the region of the grounding line where the inland ice goes afloat. By improving the accuracy and resolution of these data, which are fed into predictive numerical models, the team will help to constrain the magnitude and rate of increase in the contribution of ice from Thwaites Glacier to the global ocean.\u003cbr/\u003e\u003cbr/\u003eThe team will enhance the capabilities of the already planned British Antarctic Survey aerogeophysics survey of Thwaites Glacier during the 2018/19 field season. Their Inertial Measurement Unit will be paired with a state-of-the-art commercial gravity meter to acquire high-quality and significantly enhanced resolution data both over the ice shelf and at the grounding line. Data will be processed immediately following collection and raw and observed data will be released six months after collection.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -104.0, "geometry": "POINT(-109.5 -75)", "instruments": null, "is_usap_dc": true, "keywords": "GRAVITY; Antarctica", "locations": "Antarctica", "north": -74.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Instrumentation and Support; Antarctic Integrated System Science; Antarctic Instrumentation and Facilities", "paleo_time": null, "persons": "Tinto, Kirsty", "platforms": null, "repo": "UK PDC", "repositories": "UK PDC", "science_programs": "Thwaites (ITGC)", "south": -76.0, "title": "RAPID: High-Resolution Gravity for Thwaites Glacier", "uid": "p0010077", "west": -115.0}, {"awards": "1341496 Girton, James", "bounds_geometry": "POLYGON((-142 -66,-135.3 -66,-128.6 -66,-121.9 -66,-115.2 -66,-108.5 -66,-101.8 -66,-95.1 -66,-88.4 -66,-81.7 -66,-75 -66,-75 -66.8,-75 -67.6,-75 -68.4,-75 -69.2,-75 -70,-75 -70.8,-75 -71.6,-75 -72.4,-75 -73.2,-75 -74,-81.7 -74,-88.4 -74,-95.1 -74,-101.8 -74,-108.5 -74,-115.2 -74,-121.9 -74,-128.6 -74,-135.3 -74,-142 -74,-142 -73.2,-142 -72.4,-142 -71.6,-142 -70.8,-142 -70,-142 -69.2,-142 -68.4,-142 -67.6,-142 -66.8,-142 -66))", "dataset_titles": "Bottom Photographs from the Antarctic Peninsula acquired during R/V Laurence M. Gould expedition LMG1703; Expedition Data; Expedition data of NBP1701", "datasets": [{"dataset_uid": "001369", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1701"}, {"dataset_uid": "601302", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Benthic Images; Benthos; Biota; LMG1708; Oceans; Photo; Photo/video; Photo/Video; R/v Laurence M. Gould; Ship; Yoyo Camera", "people": "Girton, James", "repository": "USAP-DC", "science_program": null, "title": "Bottom Photographs from the Antarctic Peninsula acquired during R/V Laurence M. Gould expedition LMG1703", "url": "https://www.usap-dc.org/view/dataset/601302"}, {"dataset_uid": "002661", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1701", "url": "https://www.rvdata.us/search/cruise/NBP1701"}], "date_created": "Tue, 10 Dec 2019 00:00:00 GMT", "description": "Current oceanographic interest in the interaction of relatively warm water of the Southern Ocean Circumpolar Deep Water (CDW) as it moves southward to the frigid waters of the Antarctic continental shelves is based on the potential importance of heat transport from the global ocean to the base of continental ice shelves. This is needed to understand the longer term mass balance of the continent, the stability of the vast Antarctic ice sheets and the rate at which sea-level will rise in a warming world. Improved observational knowledge of the mechanisms of how warming CDW moves across the Antarctic Circumpolar Current (ACC) is needed. Understanding this dynamical transport, believed to take place through the eddy flux of time-varying mesoscale circulation features, will improve coupled ocean-atmospheric climate models. The development of the next generation of coupled ocean-ice-climate models help us understand future changes in atmospheric heat fluxes, glacial and sea-ice balance, and changes in the Antarctic ecosystems. A recurring obstacle to our understanding is the lack of data in this distant region. In this project, a total of 10 subsurface profiling EM-APEX floats adapted to operate under sea ice were launched in 12 missions (and 2 recoveries) from 4 cruises of opportunity to the Amundsen Sea sector of the Antarctic continental margin during Austral summer. The floats were launched south of the Polar Front and measured shear, turbulence, temperature, and salinity to 2000m depth for 1-2 year missions while drifting with the CDW layer between profiles.", "east": -75.0, "geometry": "POINT(-108.5 -70)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERA", "is_usap_dc": true, "keywords": "OCEAN TEMPERATURE; R/V NBP; USAP-DC; ICE DEPTH/THICKNESS; HEAT FLUX; OCEAN CURRENTS; SALINITY/DENSITY; LMG1703; Bellingshausen Sea; Yoyo Camera; WATER MASSES; R/V LMG; NBP1701", "locations": "Bellingshausen Sea", "north": -66.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Girton, James; Rynearson, Tatiana", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -74.0, "title": "Collaborative Research: Pathways of Circumpolar Deep Water to West Antarctica from Profiling Float and Satellite Measurements", "uid": "p0010074", "west": -142.0}, {"awards": "1444167 Detrich, H. William", "bounds_geometry": "POLYGON((-70 -58,-68.5 -58,-67 -58,-65.5 -58,-64 -58,-62.5 -58,-61 -58,-59.5 -58,-58 -58,-56.5 -58,-55 -58,-55 -59.8,-55 -61.6,-55 -63.4,-55 -65.2,-55 -67,-55 -68.8,-55 -70.6,-55 -72.4,-55 -74.2,-55 -76,-56.5 -76,-58 -76,-59.5 -76,-61 -76,-62.5 -76,-64 -76,-65.5 -76,-67 -76,-68.5 -76,-70 -76,-70 -74.2,-70 -72.4,-70 -70.6,-70 -68.8,-70 -67,-70 -65.2,-70 -63.4,-70 -61.6,-70 -59.8,-70 -58))", "dataset_titles": "Assembled Contig Dat for Daane et al. (2019); E-MTAB-6759: RNA-seq across tissues in four Notothenioid species (Antarctic icefish); Expedition Data of LMG1603; Expedition Data of LMG1604; Expedition Data of LMG1605; Expedition Data of LMG1803; Expedition Data of LMG1804; Expedition Data of LMG1805; Full raw data set, computer code, and evolutionary trajectories for all species in Damsgaard et al. (2019); Histology-, CT-, ultrasound-, and MRI-scans (~2 TB) for Damsgaard et al. (2019); PRJNA420419: Genome and Transcriptome Data for Kim et al. (2019) Blackfin Icefish Genome; PRJNA531677: Sequencing Data for Daane et al. (2019); S-BSST132: Assembled Transcriptomes for Berthelot et al. (2018); SRP047484 RAD-tag Sequences of Genetically Mapped Notothenia coriiceps embryos; SRP118539: RAD-tag Sequences of Genetically Mapped Chaenocephalus aceratus Embryos; Transposable element sequences and genome sizes, refs 142597 to MF142757", "datasets": [{"dataset_uid": "200252", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of LMG1604", "url": "https://www.rvdata.us/search/cruise/LMG1604"}, {"dataset_uid": "200251", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of LMG1804", "url": "https://www.rvdata.us/search/cruise/LMG1804"}, {"dataset_uid": "200092", "doi": "", "keywords": null, "people": null, "repository": "NCBI BioProject", "science_program": null, "title": "PRJNA420419: Genome and Transcriptome Data for Kim et al. (2019) Blackfin Icefish Genome", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=prjna420419"}, {"dataset_uid": "200093", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "SRP118539: RAD-tag Sequences of Genetically Mapped Chaenocephalus aceratus Embryos", "url": "https://www.ncbi.nlm.nih.gov/sra/SRP118539 "}, {"dataset_uid": "200094", "doi": "", "keywords": null, "people": null, "repository": "Array Express", "science_program": null, "title": "E-MTAB-6759: RNA-seq across tissues in four Notothenioid species (Antarctic icefish)", "url": "https://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-6759/"}, {"dataset_uid": "200095", "doi": "", "keywords": null, "people": null, "repository": "BioStudies", "science_program": null, "title": "S-BSST132: Assembled Transcriptomes for Berthelot et al. (2018)", "url": "https://www.ebi.ac.uk/biostudies/studies/S-BSST132"}, {"dataset_uid": "200096", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "SRP047484 RAD-tag Sequences of Genetically Mapped Notothenia coriiceps embryos", "url": "https://www.ncbi.nlm.nih.gov/sra/?term=SRP047484"}, {"dataset_uid": "200098", "doi": "", "keywords": null, "people": null, "repository": "NCBI BioProject", "science_program": null, "title": "PRJNA531677: Sequencing Data for Daane et al. (2019)", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA531677"}, {"dataset_uid": "200099", "doi": "10.5281/zenodo.2628936", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Assembled Contig Dat for Daane et al. (2019)", "url": "https://zenodo.org/record/2628936#.Xegqj3dFw2w"}, {"dataset_uid": "200102", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Transposable element sequences and genome sizes, refs 142597 to MF142757", "url": "https://www.ncbi.nlm.nih.gov/nuccore?LinkName=pubmed_nuccore\u0026from_uid=29739320"}, {"dataset_uid": "200103", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Full raw data set, computer code, and evolutionary trajectories for all species in Damsgaard et al. (2019)", "url": "https://github.com/elifesciences-publications/Retinaevolution"}, {"dataset_uid": "200104", "doi": "", "keywords": null, "people": null, "repository": "eLife", "science_program": null, "title": "Histology-, CT-, ultrasound-, and MRI-scans (~2 TB) for Damsgaard et al. (2019)", "url": "https://retinaevolution.bios.au.dk/eLife%20documentation/README.txt"}, {"dataset_uid": "200254", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of LMG1805", "url": "https://www.rvdata.us/search/cruise/LMG1805"}, {"dataset_uid": "200253", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of LMG1605", "url": "https://www.rvdata.us/search/cruise/LMG1605"}, {"dataset_uid": "200249", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of LMG1803", "url": "https://www.rvdata.us/search/cruise/LMG1803"}, {"dataset_uid": "200250", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of LMG1603", "url": "https://www.rvdata.us/search/cruise/LMG1603"}], "date_created": "Wed, 04 Dec 2019 00:00:00 GMT", "description": "Antarctic fish and their early developmental stages are an important component of the food web that sustains life in the cold Southern Ocean (SO) that surrounds Antarctica. They feed on smaller organisms and in turn are eaten by larger animals, including seals and killer whales. Little is known about how rising ocean temperatures will impact the development of Antarctic fish embryos and their growth after hatching. This project will address this gap by assessing the effects of elevated temperatures on embryo viability, on the rate of embryo development, and on the gene \"toolkits\" that respond to temperature stress. One of the two species to be studied does not produce red blood cells, a defect that may make its embryos particularly vulnerable to heat. The outcomes of this research will provide the public and policymakers with \"real world\" data that are necessary to inform decisions and design strategies to cope with changes in the Earth\u0027s climate, particularly with respect to protecting life in the SO. The project will also further the NSF goals of training new generations of scientists, including providing scientific training for undergraduate and graduate students, and of making scientific discoveries available to the general public. This includes the unique educational opportunity for undergraduates to participate in research in Antarctica and engaging the public in several ways, including the development of professionally-produced educational videos with bi-lingual \r\nclosed captioning. \r\nSince the onset of cooling of the SO about 40 million years ago, evolution of Antarctic marine organisms has been driven by the development of cold temperatures. Because body temperatures of Antarctic fishes fall in a narrow range determined by their habitat (-1.9 to +2.0 C), they are particularly attractive models for understanding how organismal physiology and biochemistry have been shaped to maintain life in a cooling environment. Yet these fishes are now threatened by rapid warming of the SO. The long-term objective of this project is to understand the capacities of Antarctic fishes to acclimatize and/or adapt to oceanic warming through analysis of their underlying genetic \"toolkits.\" This objective will be accomplished through three Specific Aims: 1) assessing the effects of elevated temperatures on gene expression during development of embryos; 2) examining the effects of elevated temperatures on embryonic morphology and on the temporal and spatial patterns of gene expression; and 3) evaluating the evolutionary mechanisms that have led to the loss of the red blood cell genetic program by the white-blooded fishes. Aims 1 and 2 will be investigated by acclimating experimental embryos of both red-blooded and white-blooded fish to elevated temperatures. Differential gene expression will be examined through the use of high throughput RNA sequencing. The temporal and spatial patterns of gene expression in the context of embryonic morphology (Aim 2) will be determined by microscopic analysis of embryos \"stained\" with (hybridized to) differentially expressed gene probes revealed by Aim 1; other key developmental marker genes will also be used. The genetic lesions resulting from loss of red blood cells by the white-blooded fishes (Aim 3) will be examined by comparing genes and genomes in the two fish groups.", "east": -55.0, "geometry": "POINT(-62.5 -67)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; Polar; South Shetland Islands; USAP-DC; COASTAL", "locations": "Polar; South Shetland Islands", "north": -58.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Detrich, H. William", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "R2R", "repositories": "Array Express; BioStudies; eLife; GitHub; NCBI BioProject; NCBI GenBank; NCBI SRA; R2R; Zenodo", "science_programs": null, "south": -76.0, "title": "Antarctic Notothenioid Fishes: Sentinel Taxa for Southern Ocean Warming", "uid": "p0010073", "west": -70.0}, {"awards": "1443296 Cottle, John", "bounds_geometry": "POLYGON((-180 -76.85314,-179.4383642 -76.85314,-178.8767284 -76.85314,-178.3150926 -76.85314,-177.7534568 -76.85314,-177.191821 -76.85314,-176.6301852 -76.85314,-176.0685494 -76.85314,-175.5069136 -76.85314,-174.9452778 -76.85314,-174.383642 -76.85314,-174.383642 -77.658865,-174.383642 -78.46459,-174.383642 -79.270315,-174.383642 -80.07604,-174.383642 -80.881765,-174.383642 -81.68749,-174.383642 -82.493215,-174.383642 -83.29894,-174.383642 -84.104665,-174.383642 -84.91039,-174.9452778 -84.91039,-175.5069136 -84.91039,-176.0685494 -84.91039,-176.6301852 -84.91039,-177.191821 -84.91039,-177.7534568 -84.91039,-178.3150926 -84.91039,-178.8767284 -84.91039,-179.4383642 -84.91039,180 -84.91039,177.4459565 -84.91039,174.891913 -84.91039,172.3378695 -84.91039,169.783826 -84.91039,167.2297825 -84.91039,164.675739 -84.91039,162.1216955 -84.91039,159.567652 -84.91039,157.0136085 -84.91039,154.459565 -84.91039,154.459565 -84.104665,154.459565 -83.29894,154.459565 -82.493215,154.459565 -81.68749,154.459565 -80.881765,154.459565 -80.07604,154.459565 -79.270315,154.459565 -78.46459,154.459565 -77.658865,154.459565 -76.85314,157.0136085 -76.85314,159.567652 -76.85314,162.1216955 -76.85314,164.675739 -76.85314,167.2297825 -76.85314,169.783826 -76.85314,172.3378695 -76.85314,174.891913 -76.85314,177.4459565 -76.85314,-180 -76.85314))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 02 Dec 2019 00:00:00 GMT", "description": "Subduction takes place at convergent plate boundaries and involves sinking of one tectonic plate underneath another. Although this process is a key aspect of plate tectonics that shapes the planet over geologic time, and is a primary cause of earthquakes, it is not known what causes subduction to cease, and what effect it has on the deepest portions of the crust and the upper part of the mantle. By studying the age and composition of igneous rocks emplaced at the very end of the subduction cycle, this project seeks to understand what causes subduction to cease, and how this changes the composition and structure of the crust and upper mantle. Because this process occurs deep within the earth, the project will focus on rocks in the root of an ancient subduction zone, now exposed in the Transantarctic Mountains of Antarctica. In addition, Antarctica remains relatively poorly understood, and this project will contribute directly to increasing our understanding of the geologic history of this region. The project will focus on training graduate and undergraduate students - incorporating hands-on experience with an array of state-of-the-art analytical instrumentation. Students will also gain a range of more general skills including Geographic Information Systems (GIS), written and oral communication, and data management - strengths that are highly relevant to careers both in the academic and Geosciences industry. Each summer, high school students will be incorporated into aspects of the laboratory-based research through the UCSB research mentorship program. The PI and graduate students will engage the general public through a purpose-built iPhone App and multimedia website. Activities will include live phone and video conversations from the field between elementary school students and members of the team in Antarctica. \u003cbr/\u003e\u003cbr/\u003eThe mechanisms by which the deep crustal delaminates or \"founders\" and is returned to the mantle remains a fundamental problem in earth science. Specifically, little is known about the temporal and spatial scales over which this process occurs or the mechanisms that trigger such catastrophic events. Igneous rocks highly enriched in potassium, called lamprophyres, are often emplaced during, and immediately after, termination of subduction and therefore potentially provide direct insight into foundering. These enigmatic rocks are important because they represent near-primary mantle melt compositions and therefore their age, geochemistry and petrologic evolution reveal key information on both the composition of the upper mantle and its thermal state. Of equal importance, they reveal how these key parameters vary through both space and time. By evaluating lamprophyres along a subduction zone margin it is possible to extract: 1) local-scale information, such as the timing and duration of melting and the role of igneous crystallization processes in generation of isotopic heterogeneities; 2) along-strike variations in mantle source composition, temperature, and depth of melting 3) the plate-scale forces that control foundering and termination of subduction. This project will study a suite of lamprophyres along the axis of the Transantarctic Mountains, emplaced during the latest stages of the Neoproterozoic - Ordovician Ross orogeny, Antarctica (roughly 505 to 470 million years before present). High-precision geochronology (age determinations) will be combined with geochemical measurements on the rocks and minerals to understand the mechanisms and timing of deep crustal foundering/delamination.", "east": -174.383642, "geometry": "POINT(170.0379615 -80.881765)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "AGE DETERMINATIONS; ISOTOPES; PLATE TECTONICS; Antarctica; USAP-DC; NOT APPLICABLE", "locations": "Antarctica", "north": -76.85314, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Cottle, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repositories": null, "science_programs": null, "south": -84.91039, "title": "Petrologic Constraints on Subduction Termination From Lamprophyres, Ross Orogen, Antarctica", "uid": "p0010071", "west": 154.459565}, {"awards": "1443371 Fountain, Andrew", "bounds_geometry": "POLYGON((160.2 -77.1,160.57 -77.1,160.94 -77.1,161.31 -77.1,161.68 -77.1,162.05 -77.1,162.42 -77.1,162.79 -77.1,163.16 -77.1,163.53 -77.1,163.9 -77.1,163.9 -77.196,163.9 -77.292,163.9 -77.388,163.9 -77.484,163.9 -77.58,163.9 -77.676,163.9 -77.772,163.9 -77.868,163.9 -77.964,163.9 -78.06,163.53 -78.06,163.16 -78.06,162.79 -78.06,162.42 -78.06,162.05 -78.06,161.68 -78.06,161.31 -78.06,160.94 -78.06,160.57 -78.06,160.2 -78.06,160.2 -77.964,160.2 -77.868,160.2 -77.772,160.2 -77.676,160.2 -77.58,160.2 -77.484,160.2 -77.388,160.2 -77.292,160.2 -77.196,160.2 -77.1))", "dataset_titles": "McMurdo Dry Valleys LTER: A digital archive of human activity in the McMurdo Dry Valleys, Antarctica from 1902 to present", "datasets": [{"dataset_uid": "200086", "doi": "10.6073/pasta/0725cbd31f2af4bca2c6ad145e38dd3a", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "McMurdo Dry Valleys LTER: A digital archive of human activity in the McMurdo Dry Valleys, Antarctica from 1902 to present", "url": "https://doi.org/10.6073/pasta/0725cbd31f2af4bca2c6ad145e38dd3a"}], "date_created": "Thu, 21 Nov 2019 00:00:00 GMT", "description": "Beginning with the discovery of a \"curious valley\" in 1903 by Captain Scott, the McMurdo Dry Valleys (MDV) in Antarctica have been impacted by humans, although there were only three brief visits prior to 1950. Since the late 1950\u0027s, human activity in the MDV has become commonplace in summer, putting pressure on the region\u0027s fragile ecosystems through camp construction and inhabitation, cross-valley transport on foot and via vehicles, and scientific research that involves sampling and deployment of instruments. Historical photographs, put alongside information from written documentation, offer an invaluable record of the changing patterns of human activity in the MDV. Photographic images often show the physical extent of field camps and research sites, the activities that were taking place, and the environmental protection measures that were being followed. Historical photographs of the MDV, however, are scattered in different places around the world, often in private collections, and there is a real danger that many of these photos may be lost, along with the information they contain. This project will collect and digitize historical photographs of sites of human activity in the MDV from archives and private collections in the United States, New Zealand, and organize them both chronologically and spatially in a GIS database. Sites of past human activities will be re-photographed to provide comparisons with the present, and re-photography will assist in providing spatial data for historical photographs without obvious location information. The results of this analysis will support effective environmental management into the future. The digital photo archive will be openly available through the McMurdo Dry Valleys Long Term Ecological Research (MCM LTER) website (www.mcmlter.org), where it can be used by scientists, environmental managers, and others interested in the region. \u003cbr/\u003e\u003cbr/\u003eThe central question of this project can be reformulated as a hypothesis: Despite an overall increase in human activities in the MDV, the spatial range of these activities has become more confined over time as a result of an increased awareness of ecosystem fragility and efforts to manage the region. To address this hypothesis, the project will define the spatial distribution and temporal frequency of human activity in the MDV. Photographs and reports will be collected from archives with polar collections such as the National Archives of New Zealand in Wellington and Christchurch and the Byrd Polar Research Center in Ohio. Private photograph collections will be accessed through personal connections, social media, advertisements in periodicals such as The Polar Times, and other means. Re-photography in the field will follow established techniques and will create benchmarks for future research projects. The spatial data will be stored in an ArcGIS database for analysis and quantification of the human footprint over time in the MDV. The improved understanding of changing patterns of human activity in the MDV provided by this historical photo archive will provide three major contributions: 1) a fundamentally important historic accounting of human activity to support current environmental management of the MDV; 2) defining the location and type of human activity will be of immediate benefit in two important ways: a) places to avoid for scientists interested in sampling pristine landscapes, and, b) targets of opportunity for scientists investigating the long-term environmental legacy of human activity; and 3) this research will make an innovative contribution to knowledge of the environmental history of the MDV.", "east": 163.9, "geometry": "POINT(162.05 -77.58)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "CONTAMINANT LEVELS/SPILLS; Antarctica; NOT APPLICABLE; USAP-DC", "locations": "Antarctica", "north": -77.1, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Fountain, Andrew; Howkins, Adrian", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "EDI", "repositories": "EDI", "science_programs": null, "south": -78.06, "title": "Collaborative Research: Assessing Changing Patterns of Human Activity in the McMurdo Dry Valleys using Digital Photo Archives", "uid": "p0010066", "west": 160.2}, {"awards": "1738942 Wellner, Julia", "bounds_geometry": "POLYGON((-120 -71,-118 -71,-116 -71,-114 -71,-112 -71,-110 -71,-108 -71,-106 -71,-104 -71,-102 -71,-100 -71,-100 -71.5,-100 -72,-100 -72.5,-100 -73,-100 -73.5,-100 -74,-100 -74.5,-100 -75,-100 -75.5,-100 -76,-102 -76,-104 -76,-106 -76,-108 -76,-110 -76,-112 -76,-114 -76,-116 -76,-118 -76,-120 -76,-120 -75.5,-120 -75,-120 -74.5,-120 -74,-120 -73.5,-120 -73,-120 -72.5,-120 -72,-120 -71.5,-120 -71))", "dataset_titles": "A multibeam-bathymetric compilation for the southern Amundsen Sea shelf, 1999-2019; Expedition Data of NBP2002; NBP1902 Expedition data; Physical and geochemical data from sediment cores collected offshore Thwaites Glacier", "datasets": [{"dataset_uid": "200083", "doi": "10.7284/908147", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1902 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1902"}, {"dataset_uid": "601514", "doi": "10.15784/601514", "keywords": "Antarctica; Chemistry:sediment; Chemistry:Sediment; Glaciomarine Sediment; Grain Size; Magnetic Susceptibility; Marine Geoscience; Marine Sediments; NBP1902; NBP2002; Physical Properties; R/v Nathaniel B. Palmer; Sediment Core Data; Thwaites Glacier; Trace Elements; XRF", "people": "Lepp, Allison", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Physical and geochemical data from sediment cores collected offshore Thwaites Glacier", "url": "https://www.usap-dc.org/view/dataset/601514"}, {"dataset_uid": "200161", "doi": "10.5285/F2DFEDA9-BF44-4EF5-89A3-EE5E434A385C", "keywords": null, "people": null, "repository": "UK PDC", "science_program": null, "title": "A multibeam-bathymetric compilation for the southern Amundsen Sea shelf, 1999-2019", "url": "https://doi.org/10.5285/F2DFEDA9-BF44-4EF5-89A3-EE5E434A385C"}, {"dataset_uid": "200248", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP2002", "url": "https://www.rvdata.us/search/cruise/NBP2002"}], "date_created": "Fri, 01 Nov 2019 00:00:00 GMT", "description": "This project contributes to the joint initiative launched by the U.S. National Science Foundation (NSF) and the U.K. Natural Environment Research Council (NERC) to substantially improve decadal and longer-term projections of ice loss and sea-level rise originating from Thwaites Glacier in West Antarctica. Satellite observations extending over the last 25 years show that Thwaites Glacier is rapidly thinning and accelerating. Over this same period, the Thwaites grounding line, the point at which the glacier transitions from sitting on the seabed to floating, has retreated. Oceanographic studies demonstrate that the main driver of these changes is incursion of warm water from the deep ocean that flows beneath the floating ice shelf and causes basal melting. The period of satellite observation is not long enough to determine how a large glacier, such as Thwaites, responds to long-term and near-term changes in the ocean or the atmosphere. As a result, records of glacier change from the pre-satellite era are required to build a holistic understanding of glacier behavior. Ocean-floor sediments deposited at the retreating grounding line and further offshore contain these longer-term records of changes in the glacier and the adjacent ocean. An additional large unknown is the topography of the seafloor and how it influences interactions of landward-flowing warm water with Thwaites Glacier and affects its stability. Consequently, this project focuses on the seafloor offshore from Thwaites Glacier and the records of past glacial and ocean change contained in the sediments deposited by the glacier and surrounding ocean.\u003cbr/\u003e\u003cbr/\u003eUncertainty in model projections of the future of Thwaites Glacier will be significantly reduced by cross-disciplinary investigations seaward of the current grounding line, including extracting the record of decadal to millennial variations in warm water incursion, determining the pre-satellite era history of grounding-line migration, and constraining the bathymetric pathways that control flow of warm water to the grounding line. Sedimentary records and glacial landforms preserved on the seafloor will allow reconstruction of changes in drivers and the glacial response to them over a range of timescales, thus providing reference data that can be used to initiate and evaluate the reliability of models. Such data will further provide insights on the influence of poorly understood processes on marine ice sheet dynamics. This project will include an integrated suite of marine and sub-ice shelf research activities aimed at establishing boundary conditions seaward of the Thwaites Glacier grounding line, obtaining records of the external drivers of change, improving knowledge of processes leading to collapse of Thwaites Glacier, and determining the history of past change in grounding line migration and conditions at the glacier base. These objectives will be achieved through high-resolution geophysical surveys of the seafloor and analysis of sediments collected in cores from the inner shelf seaward of the Thwaites Glacier grounding line using ship-based equipment, and from beneath the ice shelf using a corer deployed through the ice shelf via hot water drill holes.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -100.0, "geometry": "POINT(-110 -73.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS", "is_usap_dc": true, "keywords": "BATHYMETRY; Antarctica; MARINE SEDIMENTS; AMD; MARINE GEOPHYSICS; Amd/Us; USAP-DC; Thwaites Glacier; LABORATORY; Southern Ocean; ICE SHEETS; USA/NSF; GLACIERS/ICE SHEETS; R/V NBP", "locations": "Antarctica; Southern Ocean; Thwaites Glacier", "north": -71.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": null, "persons": "Wellner, Julia; Larter, Robert; Minzoni, Rebecca; Hogan, Kelly; Anderson, John; Graham, Alastair; Hillenbrand, Claus-Dieter; Nitsche, Frank O.; Simkins, Lauren; Smith, James A.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; UK PDC; USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -76.0, "title": "NSF-NERC: THwaites Offshore Research (THOR)", "uid": "p0010062", "west": -120.0}, {"awards": "1443578 Schmidt, Steven", "bounds_geometry": "POLYGON((161.5 -77.5,161.7 -77.5,161.9 -77.5,162.1 -77.5,162.3 -77.5,162.5 -77.5,162.7 -77.5,162.9 -77.5,163.1 -77.5,163.3 -77.5,163.5 -77.5,163.5 -77.53,163.5 -77.56,163.5 -77.59,163.5 -77.62,163.5 -77.65,163.5 -77.68,163.5 -77.71,163.5 -77.74,163.5 -77.77,163.5 -77.8,163.3 -77.8,163.1 -77.8,162.9 -77.8,162.7 -77.8,162.5 -77.8,162.3 -77.8,162.1 -77.8,161.9 -77.8,161.7 -77.8,161.5 -77.8,161.5 -77.77,161.5 -77.74,161.5 -77.71,161.5 -77.68,161.5 -77.65,161.5 -77.62,161.5 -77.59,161.5 -77.56,161.5 -77.53,161.5 -77.5))", "dataset_titles": "16S and 18S amplicon sequencing of Antarctic cryoconite holes; Genomes of Antarctic ssDNA viruses (GenBank accession numbers MN311489-MN311492 and MN328267-MN328291); Metadata from samples (in the process of submitting to EDI; will update with DOI once completed); Microbial species-area relationships in Antarctic cryoconite holes; Soil microbial communities of a mountain landscape, McMurdo Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "200081", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "16S and 18S amplicon sequencing of Antarctic cryoconite holes", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA480849/"}, {"dataset_uid": "200281", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Microbial species-area relationships in Antarctic cryoconite holes", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA668398/"}, {"dataset_uid": "200084", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Genomes of Antarctic ssDNA viruses (GenBank accession numbers MN311489-MN311492 and MN328267-MN328291)", "url": ""}, {"dataset_uid": "200280", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Soil microbial communities of a mountain landscape, McMurdo Dry Valleys, Antarctica", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA721735/"}, {"dataset_uid": "200279", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Metadata from samples (in the process of submitting to EDI; will update with DOI once completed)", "url": "https://github.com/pacificasommers/Cryoconite-metadata"}], "date_created": "Fri, 01 Nov 2019 00:00:00 GMT", "description": "Cryoconite holes are pockets of life completely encased in otherwise barren glacial ice. These pockets of life form when dust blown onto the ice melts a small, largely isolated hole that can function as its own tiny ecosystem. This dust can contain microorganisms such as bacteria, algae, or microscopic animals. The microorganisms within the hole interact and carry out functions typical of a larger ecosystem, such as a forest. Cryoconite holes are especially important in extreme cold environments such as the Antarctic Dry Valleys, where they function as repositories of life. Because cryoconite holes are mostly enclosed and persist for years, they can be tracked over time to test fundamental scientific questions about how communities of interacting organisms develop to become fully functioning ecosystems. This project will sample existing and experimentally created cryoconite holes to understand how these ecosystems develop and to what degree random processes (such as which organisms get there first) affect the final community composition and functioning. The results will not only improve our understanding of how microbial communities assemble and affect the functioning of microecosystems such as cryoconite holes, but also how the processes of community assembly affect functioning of larger ecosystems, such as forests. A better understanding of community establishment, development, and response to abiotic factors are essential to forecasting ecological responses to environmental change.\u003cbr/\u003e\u003cbr/\u003eIt is essential to unravel the links between community assembly, biodiversity, and nutrient cycling across numerous ecosystems because these are critical factors determining ecological responses to environmental change. The unique, largely isolated nature of cryoconite holes provides an experimental system that will advance fundamental understanding of the processes (e.g., stochastic dynamics such as dispersal limitation, assembly order, and ecological drift) driving community assembly. This project will use a field sampling campaign and a number of manipulative experiments to test a hypothesis that unites theory in community and ecosystem ecology: the degree to which stochastic processes guide microbial community assembly and affects regional patterns in biodiversity and ecosystem processes. Cryoconite holes will be sampled to compare community composition, environmental factors, and ecosystem functioning between hydrologically connected and isolated holes. New cryoconite holes will also be constructed and monitored over the course of two growing seasons to specifically alter assembly order and community size, thereby pairing a unique manipulative experiment with field surveys to address questions with relevance to the Antarctic and beyond. Amplicon sequencing, metagenomics, microscopy, sensitive environmental chemistry methods, and photosynthesis and respiration measurements will be used to test a series of sub-hypotheses that relate stochasticity to patterns in regional biodiversity, heterogeneity in environmental factors, and ecosystem processes.", "east": 163.5, "geometry": "POINT(162.5 -77.65)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "GLACIERS; Antarctica; USAP-DC; FIELD INVESTIGATION", "locations": "Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Schmidt, Steven; Cawley, Kaelin; Fountain, Andrew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "NCBI GenBank", "repositories": "GitHub; NCBI GenBank", "science_programs": null, "south": -77.8, "title": "Collaborative Research: Stochasticity and Cryoconite Community Assembly and Function", "uid": "p0010063", "west": 161.5}, {"awards": "1142646 Twickler, Mark; 1142517 Aydin, Murat; 1141839 Steig, Eric", "bounds_geometry": "POINT(90 -90)", "dataset_titles": "South Pole Ice Core Holocene Major Ion Dataset; South Pole ice core (SPC14) discrete methane data; South Pole Ice Core (SPICEcore) SPC14 Core Quality Versus Depth; SP19 Gas Chronology; Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "datasets": [{"dataset_uid": "601221", "doi": "10.15784/601221", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Data; Ice Core Depth; Ice Core Records; Snow/ice; Snow/Ice; SPICEcore", "people": "Steig, Eric J.; Aydin, Murat; Fegyveresi, John; Twickler, Mark; Souney, Joseph Jr.; Casey, Kimberly A.; Kahle, Emma; Nicewonger, Melinda R.; Fudge, T. J.; Hargreaves, Geoff; Nunn, Richard", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core (SPICEcore) SPC14 Core Quality Versus Depth", "url": "https://www.usap-dc.org/view/dataset/601221"}, {"dataset_uid": "601399", "doi": "10.15784/601399", "keywords": "Antarctica; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Holocene Major Ion Dataset", "url": "https://www.usap-dc.org/view/dataset/601399"}, {"dataset_uid": "601396", "doi": "10.15784/601396", "keywords": "Accumulation; Antarctica; Diffusion Length; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Dynamic; Layer Thinning; Oxygen Isotope; South Pole; SPICEcore; Temperature", "people": "White, James; Buizert, Christo; Epifanio, Jenna; Waddington, Edwin D.; Conway, Howard; Stevens, Max; Schauer, Andrew; Vaughn, Bruce; Morris, Valerie; Jones, Tyler R.; Fudge, T. J.; Koutnik, Michelle; Kahle, Emma; Steig, Eric J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "url": "https://www.usap-dc.org/view/dataset/601396"}, {"dataset_uid": "601381", "doi": "10.15784/601381", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Methane; South Pole; SPICEcore", "people": "Ferris, David G.; Severinghaus, Jeffrey P.; Kahle, Emma; Sowers, Todd A.; Edwards, Jon S.; Aydin, Murat; Winski, Dominic A.; Osterberg, Erich; Kreutz, Karl; Buizert, Christo; Fudge, T. J.; Brook, Edward J.; Hood, Ekaterina; Kalk, Michael; Steig, Eric J.; Kennedy, Joshua A.; Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}, {"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}], "date_created": "Wed, 30 Oct 2019 00:00:00 GMT", "description": "This proposal requests support for a project to drill and recover a new ice core from South Pole, Antarctica. The South Pole ice core will be drilled to a depth of 1500 m, providing an environmental record spanning approximately 40 kyrs. This core will be recovered using a new intermediate drill, which is under development by the U.S. Ice Drilling Design and Operations (IDDO) group in collaboration with Danish scientists. This proposal seeks support to provide: 1) scientific management and oversight for the South Pole ice core project, 2) personnel for ice core drilling and core processing, 3) data management, and 3) scientific coordination and communication via scientific workshops. The intellectual merit of the work is that the analysis of stable isotopes, atmospheric gases, and aerosol-borne chemicals in polar ice has provided unique information about the magnitude and timing of changes in climate and climate forcing through time. The international ice core research community has articulated the goal of developing spatial arrays of ice cores across Antarctica and Greenland, allowing the reconstruction of regional patterns of climate variability in order to provide greater insight into the mechanisms driving climate change. The broader impacts of the project include obtaining the South Pole ice core will support a wide range of ice core science projects, which will contribute to the societal need for a basic understanding of climate and the capability to predict climate and ice sheet stability on long time scales. Second, the project will help train the next generation of ice core scientists by providing the opportunity for hands-on field and core processing experience for graduate students and postdoctoral researchers. A postdoctoral researcher at the University of Washington will be directly supported by this project, and many other young scientists will interact with the project through individual science proposals. Third, the project will result in the development of a new intermediate drill which will become an important resource to US ice core science community. This drill will have a light logistical footprint which will enable a wide range of ice core projects to be carried out that are not currently feasible. Finally, although this project does not request funds for outreach activities, the project will run workshops that will encourage and enable proposals for coordinated outreach activities involving the South Pole ice core science team.", "east": 90.0, "geometry": "POINT(90 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "USAP-DC; Amd/Us; Antarctica; ANALYTICAL LAB; USA/NSF; AMD; South Pole; ICE CORE RECORDS; FIELD INVESTIGATION; Ice Core", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Twickler, Mark; Souney, Joseph Jr.; Aydin, Murat; Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: A 1500m Ice Core from South Pole", "uid": "p0010060", "west": 90.0}, {"awards": "1745137 Schroeder, Dustin", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic topographic and subglacial lake geostatistical simulations; Radar Sounding Observations of the Amundsen Sea Embayment, 2004-2005", "datasets": [{"dataset_uid": "601213", "doi": "10.15784/601213", "keywords": "Active Lakes; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model; Model Data; Snow/ice; Snow/Ice; Subglacial Lakes; Topography", "people": "MacKie, Emma; Caers, Jef; Schroeder, Dustin; Scheidt, Celine; Siegfried, Matt", "repository": "USAP-DC", "science_program": null, "title": "Antarctic topographic and subglacial lake geostatistical simulations", "url": "https://www.usap-dc.org/view/dataset/601213"}, {"dataset_uid": "601436", "doi": "10.15784/601436", "keywords": "Amundsen Sea; Antarctica; Bed Reflectivity; Ice Penetrating Radar; Radar Echo Sounder", "people": "Culberg, Riley; Chu, Winnie; Hilger, Andrew M.; Schroeder, Dustin; Jordan, Thomas M.; Seroussi, Helene; Young, Duncan A.; Vaughan, David G.", "repository": "USAP-DC", "science_program": null, "title": "Radar Sounding Observations of the Amundsen Sea Embayment, 2004-2005", "url": "https://www.usap-dc.org/view/dataset/601436"}], "date_created": "Sat, 12 Oct 2019 00:00:00 GMT", "description": "Earth\u0027s geologic record shows that the great ice sheets have contributed to rates of sea-level rise that have been much higher than those observed today. That said, some sectors of the current Antarctic ice sheet are losing mass at large and accelerating rates. One of the primary challenges for placing these recent and ongoing changes in the context of geologically historic rates, and for making projections decades to centuries into the future, is the difficulty of observing conditions and processes beneath the ice sheet. Whereas satellite observations allow tracking of the ice-surface velocity and elevation on the scale of glacier catchments to ice sheets, airborne ice-penetrating radar has been the only approach for assessing conditions on this scale beneath the ice. These radar observations have been made since the late 1960s, but, because many different instruments have been used, it is difficult to track change in subglacial conditions through time. This project will develop the technical tools and approaches required to cross-compare among these measurements and thus open up opportunities for tracking and understanding changes in the critical subglacial environment. Intertwined with the research and student training on this project will be an outreach education effort to provide middle school and high school students with improved resources and enhanced exposure to geophysical, glaciological, and remote-sensing topics through partnership with the National Science Olympiad.\u003cbr/\u003e\u003cbr/\u003eThe radar sounding of ice sheets is a powerful tool for glaciological science with broad applicability across a wide range of cryosphere problems and processes. Radar sounding data have been collected with extensive spatial and temporal coverage across the West Antarctic Ice Sheet, including areas where multiple surveys provide observations that span decades in time or entire cross-catchment ice-sheet sectors. However, one major obstacle to realizing the scientific potential of existing radar sounding observations in Antarctica is the lack of analysis approaches specifically developed for cross-instrument interpretation. Radar is also spatially limited and often has gaps of many tens of kilometers between data points. Further work is needed to investigate ways of extrapolating radar information beyond the flight lines. This project aims to directly address these barriers to full utilization of the collective Antarctic radar sounding record by developing a suite of processing and interpretation techniques to enable the synthesis of radar sounding data sets collected with systems that range from incoherent to coherent, single-channel to swath-imaging, and digital to optically-recorded radar sounders. This includes a geostatistical analysis of ice sheet and radar datasets to make probabilistic predictions of conditions at the bed. The approaches will be assessed for two target regions: the Amundsen Sea Embayment and the Siple Coast. All pre- and post-processed sounding data produced by this project will be publically hosted for use by the wider research community.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e IMAGING RADAR SYSTEMS", "is_usap_dc": true, "keywords": "GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHY; Amd/Us; Airborne Radar; USA/NSF; ICE DEPTH/THICKNESS; Antarctica; Radar; AMD; USAP-DC", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Glaciology", "paleo_time": null, "persons": "Schroeder, Dustin; MacKie, Emma", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "CAREER: Cross-Instrument Synthesis of Antarctic Radar Sounding Observations", "uid": "p0010058", "west": -180.0}, {"awards": "1443190 Parizek, Byron", "bounds_geometry": "POLYGON((-130 -73,-125.5 -73,-121 -73,-116.5 -73,-112 -73,-107.5 -73,-103 -73,-98.5 -73,-94 -73,-89.5 -73,-85 -73,-85 -73.9,-85 -74.8,-85 -75.7,-85 -76.6,-85 -77.5,-85 -78.4,-85 -79.3,-85 -80.2,-85 -81.1,-85 -82,-89.5 -82,-94 -82,-98.5 -82,-103 -82,-107.5 -82,-112 -82,-116.5 -82,-121 -82,-125.5 -82,-130 -82,-130 -81.1,-130 -80.2,-130 -79.3,-130 -78.4,-130 -77.5,-130 -76.6,-130 -75.7,-130 -74.8,-130 -73.9,-130 -73))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 16 Sep 2019 00:00:00 GMT", "description": "Accurate reconstructions and predictions of glacier movement on timescales of human interest require a better understanding of available observations and the ability to model the key processes that govern ice flow. The fact that many of these processes are interconnected, are loosely constrained by data, and involve not only the ice, but also the atmosphere, ocean, and solid Earth, makes this a challenging endeavor, but one that is essential for Earth-system modeling and the resulting climate and sea-level forecasts that are provided to policymakers worldwide. Based on the amount of ice present in the West Antarctic Ice Sheet and its ability to flow and/or melt into the ocean, its complete collapse would result in a global sea-level rise of 3.3 to 5 meters, making its stability and rate of change scientific questions of global societal significance. Whether or not a collapse eventually occurs, a better understanding of the potential West Antarctic contribution to sea level over the coming decades and centuries is necessary when considering the fate of coastal population centers. Recent observations of the Amundsen Sea Embayment of West Antarctica indicate that it is experiencing faster mass loss than any other region of the continent. At present, the long-term stability of this embayment is unknown, with both theory and observations suggesting that collapse is possible. This study is focused on this critical region as well as processes governing changes in outlet glacier flow. To this end, we will test an ice-sheet model against existing observations and improve treatment of key processes within ice sheet models.\r\n\r\nThis is a four-year (one year of no-cost extension) modeling study using the open-source Ice Sheet System Model in coordination with other models to help improve projections of future sea-level change. Overall project goals, which are distributed across the collaborating institutions, are to:\r\n1. hindcast the past two-to-three decades of evolution of the Amundsen Sea Embayment sector to determine controlling processes, incorporate and test parameterizations, and assess and improve model initialization, spinup, and performance;\r\n2. utilize observations from glacial settings and efficient process-oriented models to develop a better understanding of key processes associated with outlet glacier dynamics and to create numerically efficient parameterizations for these often sub-grid-scale processes;\r\n3. project a range of evolutions of the Amundsen Sea Embayment sector in the next several centuries given various forcings and inclusion or omission of physical processes in the model.\r\n", "east": -85.0, "geometry": "POINT(-107.5 -77.5)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; Antarctica; GLACIER MOTION/ICE SHEET MOTION; NOT APPLICABLE", "locations": "Antarctica", "north": -73.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Pollard, David; Parizek, Byron R.", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repositories": null, "science_programs": null, "south": -82.0, "title": "Collaborative Research: Evaluating Retreat in the Amundsen Sea Embayment: Assessing Controlling Processes, Uncertainties, and Projections", "uid": "p0010054", "west": -130.0}, {"awards": "1443346 Stone, John; 1443248 Hall, Brenda", "bounds_geometry": "POLYGON((-174 -84.2,-172.4 -84.2,-170.8 -84.2,-169.2 -84.2,-167.6 -84.2,-166 -84.2,-164.4 -84.2,-162.8 -84.2,-161.2 -84.2,-159.6 -84.2,-158 -84.2,-158 -84.36,-158 -84.52,-158 -84.68,-158 -84.84,-158 -85,-158 -85.16,-158 -85.32,-158 -85.48,-158 -85.64,-158 -85.8,-159.6 -85.8,-161.2 -85.8,-162.8 -85.8,-164.4 -85.8,-166 -85.8,-167.6 -85.8,-169.2 -85.8,-170.8 -85.8,-172.4 -85.8,-174 -85.8,-174 -85.64,-174 -85.48,-174 -85.32,-174 -85.16,-174 -85,-174 -84.84,-174 -84.68,-174 -84.52,-174 -84.36,-174 -84.2))", "dataset_titles": "Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast; Ice-D Antarctic Cosmogenic Nuclide database - site DUNCAN; Ice-D Antarctic Cosmogenic Nuclide database - site MAASON; Liv and Amundsen Glacier Radiocarbon Data", "datasets": [{"dataset_uid": "200087", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Ice-D Antarctic Cosmogenic Nuclide database - site MAASON", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200088", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Ice-D Antarctic Cosmogenic Nuclide database - site DUNCAN", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "601226", "doi": "10.15784/601226", "keywords": "Antarctica; Be-10; Beryllium-10; Cosmogenic; Cosmogenic Dating; Cosmogenic Radionuclides; Deglaciation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Liv Glacier; Rocks; Ross Ice Sheet; Surface Exposure Dates; Transantarctic Mountains", "people": "Stone, John", "repository": "USAP-DC", "science_program": null, "title": "Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast", "url": "https://www.usap-dc.org/view/dataset/601226"}, {"dataset_uid": "601208", "doi": "10.15784/601208", "keywords": "Antarctica; Carbon; Glaciology; Holocene; Radiocarbon; Ross Embayment; Ross Sea; Transantarctic Mountains", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Liv and Amundsen Glacier Radiocarbon Data", "url": "https://www.usap-dc.org/view/dataset/601208"}], "date_created": "Thu, 05 Sep 2019 00:00:00 GMT", "description": "The response of the Antarctic Ice Sheet to future climatic changes is recognized as the greatest uncertainty in projections of future sea level. An understanding of past ice fluctuations affords insight into ice-sheet response to climate and sea-level change and thus is critical for improving sea-level predictions. This project will examine deglaciation of the southern Ross Sea over the past few thousand years to document oscillations in Antarctic ice volume during a period of relatively stable climate and sea level. We will help quantify changes in ice volume, improve understanding of the ice dynamics responsible, and examine the implications for future sea-level change. The project will train future scientists through participation of graduate students, as well as undergraduates who will develop research projects in our laboratories.\u003cbr/\u003e\u003cbr/\u003ePrevious research indicates rapid Ross Sea deglaciation as far south as Beardmore Glacier early in the Holocene epoch (which began approximately 11,700 years before present), followed by more gradual recession. However, deglaciation in the later half of the Holocene remains poorly constrained, with no chronological control on grounding-line migration between Beardmore and Scott Glaciers. Thus, we do not know if mid-Holocene recession drove the grounding line rapidly back to its present position at Scott Glacier, or if the ice sheet withdrew gradually in the absence of significant climate forcing or eustatic sea level change. The latter possibility raises concerns for future stability of the Ross Sea grounding line. To address this question, we will map and date glacial deposits on coastal mountains that constrain the thinning history of Liv and Amundsen Glaciers. By extending our chronology down to the level of floating ice at the mouths of these glaciers, we will date their thinning history from glacial maximum to present, as well as migration of the Ross Sea grounding line southwards along the Transantarctic Mountains. High-resolution dating will come from Beryllium-10 surface-exposure ages of erratics collected along elevation transects, as well as Carbon-14 dates of algae within shorelines from former ice-dammed ponds. Sites have been chosen specifically to allow close comparison of these two dating methods, which will afford constraints on Antarctic Beryllium-10 production rates.", "east": -158.0, "geometry": "POINT(-166 -85)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; NOT APPLICABLE; Antarctica; ICE SHEETS; USAP-DC", "locations": "Antarctica", "north": -84.2, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Hall, Brenda; Stone, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "ICE-D", "repositories": "ICE-D; USAP-DC", "science_programs": null, "south": -85.8, "title": "Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment", "uid": "p0010053", "west": -174.0}, {"awards": "1443663 Cole-Dai, Jihong; 1443397 Kreutz, Karl; 1443336 Osterberg, Erich", "bounds_geometry": "POINT(-180 -90)", "dataset_titles": "Preliminary SPC14 high-resolution Fe and Mn biologically relevant and dissolved trace metal concentrations spanning -42 \u2013 54,300 years BP.; South Pole Ice Core Holocene Major Ion Dataset; South Pole Ice Core Sea Salt and Major Ions; South Pole ice core (SPC14) discrete methane data; South Pole (SPC14) microparticle concentration, mass concentration, flux, particle-size-distribution mode, and aspect ratio measurements; SPICEcore 400-480 m Major Ions SDSU; The South Pole Ice Core (SPICEcore) chronology and supporting data", "datasets": [{"dataset_uid": "601754", "doi": "10.15784/601754", "keywords": "Antarctica; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Sea Salt and Major Ions", "url": "https://www.usap-dc.org/view/dataset/601754"}, {"dataset_uid": "601430", "doi": "10.15784/601430", "keywords": "Antarctica; Ions; South Pole; SPICEcore", "people": "Larrick, Carleigh; Cole-Dai, Jihong", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SPICEcore 400-480 m Major Ions SDSU", "url": "https://www.usap-dc.org/view/dataset/601430"}, {"dataset_uid": "601206", "doi": "10.15784/601206", "keywords": "Antarctica; Calcium (ca); Chemistry:ice; Chemistry:Ice; Depth; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciochemistry; Glaciology; Ice; Ice Core; Ice Core Chemistry; Ice Core Data; Ice Core Records; Ice Core Stratigraphy; Nitrate; Nitrogen Isotopes; Paleoclimate; Snow/ice; Snow/Ice; South Pole; SPICEcore", "people": "Alley, Richard; Waddington, Edwin D.; Osterberg, Erich; Buizert, Christo; Dunbar, Nelia; Beaudette, Ross; Brook, Edward J.; Fudge, T. J.; Winski, Dominic A.; Jones, Tyler R.; Kreutz, Karl; Fegyveresi, John; Cole-Dai, Jihong; McConnell, Joseph; Thundercloud, Zayta; Sigl, Michael; Cox, Thomas S.; Steig, Eric J.; Ferris, David G.; Souney, Joseph Jr.; Kahle, Emma; Aydin, Murat; Morris, Valerie; Nicewonger, Melinda R.; Bay, Ryan; Casey, Kimberly A.; Sowers, Todd A.; Iverson, Nels; Severinghaus, Jeffrey P.; Epifanio, Jenna; Ortman, Nikolas", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "The South Pole Ice Core (SPICEcore) chronology and supporting data", "url": "https://www.usap-dc.org/view/dataset/601206"}, {"dataset_uid": "601675", "doi": "10.15784/601675", "keywords": "Antarctica; South Pole; SPICEcore", "people": "Kreutz, Karl", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Preliminary SPC14 high-resolution Fe and Mn biologically relevant and dissolved trace metal concentrations spanning -42 \u2013 54,300 years BP.", "url": "https://www.usap-dc.org/view/dataset/601675"}, {"dataset_uid": "601399", "doi": "10.15784/601399", "keywords": "Antarctica; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Holocene Major Ion Dataset", "url": "https://www.usap-dc.org/view/dataset/601399"}, {"dataset_uid": "601553", "doi": "10.15784/601553", "keywords": "Antarctica; Dust; Ice Core; South Pole", "people": "Kreutz, Karl", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole (SPC14) microparticle concentration, mass concentration, flux, particle-size-distribution mode, and aspect ratio measurements", "url": "https://www.usap-dc.org/view/dataset/601553"}, {"dataset_uid": "601381", "doi": "10.15784/601381", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Methane; South Pole; SPICEcore", "people": "Ferris, David G.; Severinghaus, Jeffrey P.; Kahle, Emma; Sowers, Todd A.; Edwards, Jon S.; Aydin, Murat; Winski, Dominic A.; Osterberg, Erich; Kreutz, Karl; Buizert, Christo; Fudge, T. J.; Brook, Edward J.; Hood, Ekaterina; Kalk, Michael; Steig, Eric J.; Kennedy, Joshua A.; Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}], "date_created": "Thu, 29 Aug 2019 00:00:00 GMT", "description": "This collaborative project explores the signatures and causes of natural climate change in the region surrounding Antarctica over the last 40,000 years as the Earth transitioned from an ice age into the modern warm period. The researchers will investigate how the wind belts that surround Antarctica changed in their strength and position through time, and document explosive volcanic eruptions and CO2 cycling in the Southern Ocean as potential climate forcing mechanisms over this interval. Understanding how and why the climate varied naturally in the past is critical for improving understanding of modern climate change and projections of future climate under higher levels of atmospheric CO2. \u003cbr/\u003e\u003cbr/\u003eThe investigators plan to conduct a suite of chemical measurements along the 1500m length of the South Pole Ice Core, including major ion and trace element concentrations, and microparticle (dust) concentrations and size distributions. These measurements will (1) extend the South Pole record of explosive volcanic eruptions to 40,000 years using sulfate and particle data; (2) establish the relative timing of climate changes in dust source regions of Patagonia, New Zealand, and Australia using dust flux data; (3) investigate changes in the strength and position of the westerly wind belt using dust size distribution data; and (4) quantify the flux of bioavailable trace metals deposited as dust to the Southern Ocean over time. These chemistry records will also be critical for creating the timescale that will be used by all researchers studying records from the South Pole core. The project will support four graduate students and several undergraduate students across three different institutions, and become a focus of the investigators\u0027 efforts to disseminate outcomes of climate change science to the broader community.", "east": -180.0, "geometry": "POINT(-180 -90)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; ICE CORE RECORDS; USAP-DC; Amd/Us; USA/NSF; LABORATORY; AMD", "locations": "Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Osterberg, Erich", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements", "uid": "p0010051", "west": -180.0}, {"awards": "1443424 McMahon, Kelton; 1826712 McMahon, Kelton; 1443585 Polito, Michael; 1443386 Emslie, Steven", "bounds_geometry": "POLYGON((-180 -60,-166 -60,-152 -60,-138 -60,-124 -60,-110 -60,-96 -60,-82 -60,-68 -60,-54 -60,-40 -60,-40 -61.8,-40 -63.6,-40 -65.4,-40 -67.2,-40 -69,-40 -70.8,-40 -72.6,-40 -74.4,-40 -76.2,-40 -78,-54 -78,-68 -78,-82 -78,-96 -78,-110 -78,-124 -78,-138 -78,-152 -78,-166 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -76.2,160 -74.4,160 -72.6,160 -70.8,160 -69,160 -67.2,160 -65.4,160 -63.6,160 -61.8,160 -60,162 -60,164 -60,166 -60,168 -60,170 -60,172 -60,174 -60,176 -60,178 -60,-180 -60))", "dataset_titles": "Amino acid nitrogen isotope values of modern and ancient Ad\u00e9lie penguin eggshells from the Ross Sea and Antarctic Peninsula regions; Amino acid nitrogen isotope values of penguins from the Antarctic Peninsula region 1930s to 2010s; Ancient Adelie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica; Carbon and nitrogen stable isotope values of Antarctic Krill from the South Shetland Islands and the northern Antarctic Peninsula 2007 and 2009; Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula; Radiocarbon dating and stable isotope values of penguin and seal tissues recovered from ornithogenic soils on Platter Island, Danger Islands Archipelago, Antarctic Peninsula in December 2015.; Radioisotope dates and carbon (\u03b413C) and nitrogen (\u03b415N) stable isotope values from modern and mummified Ad\u00e9lie Penguin chick carcasses and tissue from the Ross Sea, Antarctica; Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.; Receding ice drove parallel expansions in Southern Ocean penguin; SNP data from \"Receding ice drove parallel expansions in Southern Ocean penguins\".; Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica; The rise and fall of an ancient Adelie penguin \u0027supercolony\u0027 at Cape Adare, Antarctica", "datasets": [{"dataset_uid": "601263", "doi": "10.15784/601263", "keywords": "Abandoned Colonies; Antarctica; Holocene; Penguin; Ross Sea; Stable Isotope Analysis", "people": "Patterson, William; Emslie, Steven; Kristan, Allyson", "repository": "USAP-DC", "science_program": null, "title": "Radioisotope dates and carbon (\u03b413C) and nitrogen (\u03b415N) stable isotope values from modern and mummified Ad\u00e9lie Penguin chick carcasses and tissue from the Ross Sea, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601263"}, {"dataset_uid": "601212", "doi": "10.15784/601212", "keywords": "Abandoned Colonies; Antarctica; Antarctic Peninsula; Beach Deposit; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Holocene; Penguin; Radiocarbon; Radiocarbon Dates; Snow/ice; Snow/Ice; Stranger Point", "people": "Emslie, Steven", "repository": "USAP-DC", "science_program": null, "title": "Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601212"}, {"dataset_uid": "601327", "doi": "10.15784/601327", "keywords": "Adelie Penguin; Antarctica; Biota; Cape Adare; East Antarctica; Population Movement; Pygoscelis Adeliae; Radiocarbon; Ross Sea; Sea Level Rise; Stable Isotopes", "people": "McKenzie, Ashley; Emslie, Steven; Patterson, William", "repository": "USAP-DC", "science_program": null, "title": "The rise and fall of an ancient Adelie penguin \u0027supercolony\u0027 at Cape Adare, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601327"}, {"dataset_uid": "601210", "doi": "10.15784/601210", "keywords": "Antarctica; Antarctic Krill; Antarctic Peninsula; Biota; Carbon Isotopes; Isotope Data; Krill; Nitrogen Isotopes; Oceans; Southern Ocean; Stable Isotope Analysis", "people": "Polito, Michael", "repository": "USAP-DC", "science_program": null, "title": "Carbon and nitrogen stable isotope values of Antarctic Krill from the South Shetland Islands and the northern Antarctic Peninsula 2007 and 2009", "url": "https://www.usap-dc.org/view/dataset/601210"}, {"dataset_uid": "601232", "doi": "10.15784/601232", "keywords": "Amino Acids; Antarctica; Antarctic Peninsula; Biota; Isotope Data; Nitrogen Isotopes; Oceans; Penguin; Southern Ocean; Stable Isotope Analysis", "people": "Polito, Michael; McMahon, Kelton", "repository": "USAP-DC", "science_program": null, "title": "Amino acid nitrogen isotope values of penguins from the Antarctic Peninsula region 1930s to 2010s", "url": "https://www.usap-dc.org/view/dataset/601232"}, {"dataset_uid": "601760", "doi": "10.15784/601760", "keywords": "Adelie Penguin; Amino Acids; Antarctica; Antarctic Peninsula; Ross Sea; Stable Isotope Analysis; Trophic Position", "people": "Polito, Michael; Wonder, Michael; Emslie, Steven; McCarthy, Matthew; Patterson, William; McMahon, Kelton; Michelson, Chantel", "repository": "USAP-DC", "science_program": null, "title": "Amino acid nitrogen isotope values of modern and ancient Ad\u00e9lie penguin eggshells from the Ross Sea and Antarctic Peninsula regions", "url": "https://www.usap-dc.org/view/dataset/601760"}, {"dataset_uid": "601364", "doi": "10.15784/601364", "keywords": "Antarctica; Antarctic Peninsula; Arctocephalus Gazella; Carbon; Holocene; Nitrogen; Paleoecology; Penguin; Pygoscelis Spp.; Stable Isotope Analysis; Weddell Sea", "people": "Clucas, Gemma; Polito, Michael; Kalvakaalva, Rohit; Herman, Rachael", "repository": "USAP-DC", "science_program": null, "title": "Radiocarbon dating and stable isotope values of penguin and seal tissues recovered from ornithogenic soils on Platter Island, Danger Islands Archipelago, Antarctic Peninsula in December 2015.", "url": "https://www.usap-dc.org/view/dataset/601364"}, {"dataset_uid": "601509", "doi": "10.15784/601509", "keywords": "Antarctica; Antarctic Fur Seal; Elemental Concentrations; King Penguin; Population Dynamics; South Atlantic Ocean; South Georgia Island; Stable Isotope Analysis; Sub-Antarctic", "people": "Maiti, Kanchan; Kristan, Allyson; Polito, Michael; McMahon, Kelton", "repository": "USAP-DC", "science_program": null, "title": "Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.", "url": "https://www.usap-dc.org/view/dataset/601509"}, {"dataset_uid": "601374", "doi": "10.15784/601374", "keywords": "Adelie Penguin; Antarctica; Cape Irizar; Drygalski Ice Tongue; Ross Sea; Stable Isotopes", "people": "Emslie, Steven", "repository": "USAP-DC", "science_program": null, "title": "Ancient Adelie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601374"}, {"dataset_uid": "200180", "doi": "", "keywords": null, "people": null, "repository": "NCBI BioProject", "science_program": null, "title": "Receding ice drove parallel expansions in Southern Ocean penguin", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA589336"}, {"dataset_uid": "601382", "doi": "10.15784/601382", "keywords": "25 De Mayo/King George Island; Antarctica; Biota; Delta 13C; Delta 15N; Dietary Shifts; Opportunistic Sampling; Penguin; Pygoscelis Penguins; Stranger Point", "people": "Ciriani, Yanina; Emslie, Steven", "repository": "USAP-DC", "science_program": null, "title": "Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica", "url": "https://www.usap-dc.org/view/dataset/601382"}, {"dataset_uid": "200181", "doi": "10.6084/m9.figshare.c.4475300.v1", "keywords": null, "people": null, "repository": "Figshare", "science_program": null, "title": "SNP data from \"Receding ice drove parallel expansions in Southern Ocean penguins\".", "url": "https://doi.org/10.6084/m9.figshare.c.4475300.v1"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "The Antarctic marine ecosystem is highly productive and supports a diverse range of ecologically and commercially important species. A key species in this ecosystem is Antarctic krill, which in addition to being commercially harvested, is the principle prey of a wide range of marine organisms including penguins, seals and whales. The aim of this study is to use penguins and other krill predators as sensitive indicators of past changes in the Antarctic marine food web resulting from climate variability and the historic harvesting of seals and whales by humans. Specifically this study will recover and analyze modern (\u003c20 year old), historic (20-200 year old) and ancient (200-10,000 year old) penguin and other krill predator tissues to track their past diets and population movements relative to shifts in climate and the availability of Antarctic krill. Understanding how krill predators were affected by these factors in the past will allow us to better understand how these predators, the krill they depend on, and the Antarctic marine ecosystem as a whole will respond to current challenges such as global climate change and an expanding commercial fishery for Antarctic krill. The project will further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. This project will support the cross-institutional training of undergraduate and graduate students in advanced analytical techniques in the fields of ecology and biogeochemistry. In addition, this project includes educational outreach aimed encouraging participation in science careers by engaging K-12 students in scientific issues related to Antarctica, penguins, marine ecology, biogeochemistry, and global climate change.\u003cbr/\u003e\u003cbr/\u003eThis research will help place recent ecological changes in the Southern Ocean into a larger historical context by examining decadal and millennial-scale shifts in the diets and population movements of Antarctic krill predators (penguins, seals, and squid) in concert with climate variability and commercial harvesting. This will be achieved by coupling advanced stable and radio isotope techniques, particularly compound-specific stable isotope analysis, with unprecedented access to modern, historical, and well-preserved paleo-archives of Antarctic predator tissues dating throughout the Holocene. This approach will allow the project to empirically test if observed shifts in Antarctic predator bulk tissue stable isotope values over the past millennia were caused by climate-driven shifts at the base of the food web in addition to, or rather than, shifts in predator diets due to a competitive release following the historic harvesting of krill eating whale and seals. In addition, this project will track the large-scale abandonment and reoccupation of penguin colonies around Antarctica in response to changes in climate and sea ice conditions over the past several millennia. These integrated field studies and laboratory analyses will provide new insights into the underlying mechanisms that influenced past shifts in the diets and population movements of charismatic krill predators such as penguins. This will allow for improved projections of the ecosystem consequences of future climate change and anthropogenic harvesting scenarios in the Antarctica that are likely to affect the availability of Antarctic krill.", "east": -40.0, "geometry": "POINT(-120 -69)", "instruments": null, "is_usap_dc": true, "keywords": "ANIMAL ECOLOGY AND BEHAVIOR; South Shetland Islands; Penguin; Stable Isotopes; Polar; Ross Sea; USA/NSF; Weddell Sea; AMD; MARINE ECOSYSTEMS; USAP-DC; Antarctica; PENGUINS; Southern Hemisphere; FIELD INVESTIGATION; Amd/Us; Krill; MACROFOSSILS", "locations": "Southern Hemisphere; Ross Sea; South Shetland Islands; Weddell Sea; Polar; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Polito, Michael; Emslie, Steven; Kelton, McMahon; Patterson, William; McCarthy, Matthew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "Figshare; NCBI BioProject; USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "uid": "p0010047", "west": 160.0}, {"awards": "1644073 DiTullio, Giacomo; 1643684 Saito, Mak", "bounds_geometry": "POLYGON((-180 -72,-173.6 -72,-167.2 -72,-160.8 -72,-154.4 -72,-148 -72,-141.6 -72,-135.2 -72,-128.8 -72,-122.4 -72,-116 -72,-116 -72.7,-116 -73.4,-116 -74.1,-116 -74.8,-116 -75.5,-116 -76.2,-116 -76.9,-116 -77.6,-116 -78.3,-116 -79,-122.4 -79,-128.8 -79,-135.2 -79,-141.6 -79,-148 -79,-154.4 -79,-160.8 -79,-167.2 -79,-173.6 -79,180 -79,178 -79,176 -79,174 -79,172 -79,170 -79,168 -79,166 -79,164 -79,162 -79,160 -79,160 -78.3,160 -77.6,160 -76.9,160 -76.2,160 -75.5,160 -74.8,160 -74.1,160 -73.4,160 -72.7,160 -72,162 -72,164 -72,166 -72,168 -72,170 -72,172 -72,174 -72,176 -72,178 -72,-180 -72))", "dataset_titles": "Algal pigment concentrations from the Ross Sea; Biogenic silica concentrations from the Ross Sea; NBP1801 Expedition data; Nutrients from NBP18-01 CICLOPS", "datasets": [{"dataset_uid": "601428", "doi": "10.15784/601428", "keywords": "Amundsen Sea; Antarctica; NBP1801; Nitrate; Nitrite; Nutrients; Phosphate; Ross Sea; R/v Nathaniel B. Palmer; Silicic Acid; Terra Nova Bay", "people": "Saito, Mak", "repository": "USAP-DC", "science_program": null, "title": "Nutrients from NBP18-01 CICLOPS", "url": "https://www.usap-dc.org/view/dataset/601428"}, {"dataset_uid": "601205", "doi": "10.15784/601205", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Chlorophyll; Chromatography; Liquid Chromatograph; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Sea Water; Seawater Measurements; Southern Ocean; Water Measurements; Water Samples", "people": "Ditullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Algal pigment concentrations from the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601205"}, {"dataset_uid": "200056", "doi": "10.7284/907753", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1801 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1801"}, {"dataset_uid": "601225", "doi": "10.15784/601225", "keywords": "Antarctica; Biogenic Silica; Biogenic Silica Concentrations; Chemistry:Water; Geochemistry; NBP1801; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Sea Water; Southern Ocean; Spectroscopy; Water Measurements; Water Samples", "people": "Ditullio, Giacomo; Schanke, Nicole", "repository": "USAP-DC", "science_program": null, "title": "Biogenic silica concentrations from the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601225"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "Phytoplankton blooms in the coastal waters of the Ross Sea, Antarctica are typically dominated by either diatoms or Phaeocystis Antarctica (a flagellated algae that often can form large colonies in a gelatinous matrix). The project seeks to determine if an association of bacterial populations with Phaeocystis antarctica colonies can directly supply Phaeocystis with Vitamin B12, which can be an important co-limiting micronutrient in the Ross Sea. The supply of an essential vitamin coupled with the ability to grow at lower iron concentrations may put Phaeocystis at a competitive advantage over diatoms. Because Phaeocystis cells can fix more carbon than diatoms and Phaeocystis are not grazed as efficiently as diatoms, the project will help in refining understanding of carbon dynamics in the region as well as the basis of the food web webs. Such understanding also has the potential to help refine predictive ecological models for the region. The project will conduct public outreach activities and will contribute to undergraduate and graduate research. Engagement of underrepresented students will occur during summer student internships. A collaboration with Italian Antarctic researchers, who have been studying the Terra Nova Bay ecosystem since the 1980s, aims to enhance the project and promote international scientific collaborations. \u003cbr/\u003e\u003cbr/\u003eThe study will test whether a mutualistic symbioses between attached bacteria and Phaeocystis provides colonial cells a mechanism for alleviating chronic Vitamin B12 co-limitation effects thereby conferring them with a competitive advantage over diatom communities. The use of drifters in a time series study will provide the opportunity to track in both space and time a developing algal bloom in Terra Nova Bay and to determine community structure and the physiological nutrient status of microbial populations. A combination of flow cytometry, proteomics, metatranscriptomics, radioisotopic and stable isotopic labeling experiments will determine carbon and nutrient uptake rates and the role of bacteria in mitigating potential vitamin B12 and iron limitation. Membrane inlet and proton transfer reaction mass spectrometry will also be used to estimate net community production and release of volatile organic carbon compounds that are climatically active. Understanding how environmental parameters can influence microbial community dynamics in Antarctic coastal waters will advance an understanding of how changes in ocean stratification and chemistry could impact the biogeochemistry and food web dynamics of Southern Ocean ecosystems.", "east": 160.0, "geometry": "POINT(-158 -75.5)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; NBP1801; Amd/Us; USA/NSF; USAP-DC; NUTRIENTS; PIGMENTS; CHLOROPHYLL; R/V NBP; Ross Sea; AMD", "locations": "Ross Sea", "north": -72.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "DiTullio, Giacomo; Lee, Peter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -79.0, "title": "Collaborative Research: Cobalamin and Iron Co-Limitation Of Phytoplankton Species in Terra Nova Bay", "uid": "p0010045", "west": -116.0}, {"awards": "1443420 Dodd, Justin", "bounds_geometry": "POLYGON((167.07 -77.87,167.073 -77.87,167.076 -77.87,167.079 -77.87,167.082 -77.87,167.085 -77.87,167.088 -77.87,167.091 -77.87,167.094 -77.87,167.097 -77.87,167.1 -77.87,167.1 -77.873,167.1 -77.876,167.1 -77.879,167.1 -77.882,167.1 -77.885,167.1 -77.888,167.1 -77.891,167.1 -77.894,167.1 -77.897,167.1 -77.9,167.097 -77.9,167.094 -77.9,167.091 -77.9,167.088 -77.9,167.085 -77.9,167.082 -77.9,167.079 -77.9,167.076 -77.9,167.073 -77.9,167.07 -77.9,167.07 -77.897,167.07 -77.894,167.07 -77.891,167.07 -77.888,167.07 -77.885,167.07 -77.882,167.07 -77.879,167.07 -77.876,167.07 -77.873,167.07 -77.87))", "dataset_titles": "Diatom Oxygen Isotope Evidence of Pliocene (~4.68 to 3.44 Ma) Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "datasets": [{"dataset_uid": "601220", "doi": "10.15784/601220", "keywords": "And-1B; Andrill; Antarctica; Chemistry:sediment; Chemistry:Sediment; Delta 18O; Diatom; Mass Spectrometer; Oxygen Isotope; Paleoclimate; Pliocene; Sediment; Wais Project; West Antarctic Ice Sheet", "people": "Abbott, Tirzah; Dodd, Justin", "repository": "USAP-DC", "science_program": "ANDRILL", "title": "Diatom Oxygen Isotope Evidence of Pliocene (~4.68 to 3.44 Ma) Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "url": "https://www.usap-dc.org/view/dataset/601220"}], "date_created": "Tue, 06 Aug 2019 00:00:00 GMT", "description": "Abstract\u003cbr/\u003eDuring the Early Pliocene, 4.8 to 3.4 million years ago, warmer-than-present global temperatures resulted in a retreat of the Ross Ice Shelf and West Antarctic Ice Sheet. Understanding changes in ocean dynamics during times of reduced ice volume and increased temperatures in the geologic past will improve the predictive models for these conditions. The primary goal of the proposed research is to develop a new oxygen isotope record of Pliocene oceanographic conditions near the Antarctic continent. Oxygen isotope values from the carbonate tests of benthic foraminifera have become the global standard for paleo-oceanographic studies, but foraminifera are sparse in high-latitude sediment cores. This research will instead make use of oxygen isotope measurements from diatom silica preserved in a marine sediment core from the Ross Sea. The project is the first attempt at using this method and will advance understanding of global ocean dynamics and ice sheet-ocean interactions during the Pliocene. The project will foster the professional development of two early-career scientists and serve as training for graduate and undergraduate student researchers. The PIs will use this project to introduce High School students to polar/oceanographic research, as well as stable isotope geochemistry. Collaboration with teachers via NSTA and Polar Educators International will ensure the implementation of excellent STEM learning activities and curricula for younger students. \u003cbr/\u003e\u003cbr/\u003eTechnical Description\u003cbr/\u003eThis project will produce a high-resolution oxygen isotope record from well-dated diatom rich sediments that have been cross-correlated with global benthic foraminifera oxygen isotope records. Diatom silica frustules deposited during the Early Pliocene and recovered by the ANDRILL Project (AND-1B) provide ideal material for this objective. Diatomite unites in the AND-1B core are nearly pure, with little evidence of opal formation. A diatom oxygen isotope record from this core offers the potential to constrain lingering uncertainties about Ross Sea and Southern Ocean paleoceanography and Antarctic Ice Sheet history during a time of high atmospheric carbon dioxide concentrations. Specifically, oxygen isotope variations will be used to constrain changes in the water temperature and/or freshwater flux in the Pliocene Ross Sea. Diatom species data from the AND-1B core have been used to infer variations in the extent and duration of seasonal sea ice coverage, sea surface temperatures, and mid-water advection onto the continental shelf. However, the diatom oxygen isotope record will provide the first direct measure of water/oxygen isotope values at the Antarctic continental margin during the Pliocene.", "east": 167.1, "geometry": "POINT(167.085 -77.885)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "OXYGEN ISOTOPES; USAP-DC; Antarctica; NOT APPLICABLE", "locations": "Antarctica", "north": -77.87, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Dodd, Justin; Scherer, Reed Paul; Warnock, Jonathan", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -77.9, "title": "Diatom and Oxygen Isotope Evidence of Pliocene Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "uid": "p0010042", "west": 167.07}, {"awards": "1543230 Ainley, David; 1542791 Salas, Leonardo; 1543311 LaRue, Michelle; 1543003 Stammerjohn, Sharon", "bounds_geometry": "POLYGON((-180 -64,-144 -64,-108 -64,-72 -64,-36 -64,0 -64,36 -64,72 -64,108 -64,144 -64,180 -64,180 -65.4,180 -66.8,180 -68.2,180 -69.6,180 -71,180 -72.4,180 -73.8,180 -75.2,180 -76.6,180 -78,144 -78,108 -78,72 -78,36 -78,0 -78,-36 -78,-72 -78,-108 -78,-144 -78,-180 -78,-180 -76.6,-180 -75.2,-180 -73.8,-180 -72.4,-180 -71,-180 -69.6,-180 -68.2,-180 -66.8,-180 -65.4,-180 -64))", "dataset_titles": "ContinentalWESEestimates; Counting seals from space tutorial; Fast Ice Tool; Weddell seals habitat suitability model for the Ross Sea", "datasets": [{"dataset_uid": "200045", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Fast Ice Tool", "url": "https://github.com/leosalas/FastIceCovars"}, {"dataset_uid": "200046", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Weddell seals habitat suitability model for the Ross Sea", "url": "https://github.com/leosalas/WeddellSeal_SOS"}, {"dataset_uid": "200047", "doi": "", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Counting seals from space tutorial", "url": "https://www.int-res.com/articles/suppl/m612p193_supp.pdf"}, {"dataset_uid": "200234", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "ContinentalWESEestimates", "url": "https://github.com/leosalas/ContinentalWESEestimates"}], "date_created": "Fri, 02 Aug 2019 00:00:00 GMT", "description": "The Weddell seal is the southern-most mammal in the world, having a circumpolar distribution around Antarctica; the McMurdo Sound population in Antarctica is one of the best-studied mammal populations on earth. However, despite this, an understanding of how populations around the continent will fare under climate change is poorly understood. A complicating matter is the potential effects of a commercial enterprise in the Antarctic: a fishery targeting toothfish, which are important prey for Weddell seals. Although the species is easily detected and counted during the breeding season, no reliable estimates of continent-wide Weddell seal numbers exist, due to the logistic difficulties of surveying vast regions of Antarctica. Large-scale estimates are needed to understand how seal populations are responding to the fishery and climate change, because these drivers of change operate at scales larger than any single population, and may affect seals differently in different regions of the continent. We will take advantage of the ease of detectability of darkly colored seals when they the on ice to develop estimates of abundance from satellite images. This project will generate baseline data on the global distribution and abundance of Weddell seals around the Antarctic and will link environmental variables to population changes to better understand how the species will fare as their sea ice habitat continues to change. These results will help disentangle the effects of climate change and fishery operations, results that are necessary for appropriate international policy regarding fishery catch limits, impacts on the environment, and the value of marine protected areas. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. It will engage \"arm-chair\" scientists of all ages through connections with several non-governmental organizations and the general public. Anyone with access to the internet, including people who are physically unable to participate in field research directly, can participate in this project while simultaneously learning about multiple aspects of polar ecology through the project\u0027s interactive website. \u003cbr/\u003e\u003cbr/\u003eSpecifically, this research project will: 1) Quantify the distribution of Weddell seals around Antarctica and 2) Determine the impact of environmental variables (such as fast ice extent, ocean productivity, bathymetry) on habitat suitability and occupancy. To do this, the project will crowd-source counting of seals on high-resolution satellite images via a commercial citizen science platform. Variation in seal around the continent will then be related to habitat variables through generalized linear models. Specific variables, such as fast ice extent will be tested to determine their influence on population variability through both space and time. The project includes a rigorous plan for ensuring quality control in the dataset including ground truth data from other, localized projects concurrently funded by the National Science Foundation\u0027s Antarctic Science Program.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "COASTAL; Southern Ocean; COMMUNITY DYNAMICS; MAMMALS; SEA ICE; NOT APPLICABLE; Antarctica; PENGUINS; USAP-DC", "locations": "Antarctica; Southern Ocean", "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "LaRue, Michelle; Stamatiou, Kostas", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "GitHub", "repositories": "GitHub; Publication", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Determining Factors Affecting Distribution and Population Variability of the Ice-obligate Weddell Seal", "uid": "p0010041", "west": -180.0}, {"awards": "1744645 Young, Jodi", "bounds_geometry": "POLYGON((-64.4 -64.2,-64.38 -64.2,-64.36 -64.2,-64.34 -64.2,-64.32 -64.2,-64.3 -64.2,-64.28 -64.2,-64.26 -64.2,-64.24 -64.2,-64.22 -64.2,-64.2 -64.2,-64.2 -64.26,-64.2 -64.32,-64.2 -64.38,-64.2 -64.44,-64.2 -64.5,-64.2 -64.56,-64.2 -64.62,-64.2 -64.68,-64.2 -64.74,-64.2 -64.8,-64.22 -64.8,-64.24 -64.8,-64.26 -64.8,-64.28 -64.8,-64.3 -64.8,-64.32 -64.8,-64.34 -64.8,-64.36 -64.8,-64.38 -64.8,-64.4 -64.8,-64.4 -64.74,-64.4 -64.68,-64.4 -64.62,-64.4 -64.56,-64.4 -64.5,-64.4 -64.44,-64.4 -64.38,-64.4 -64.32,-64.4 -64.26,-64.4 -64.2))", "dataset_titles": "Dataset: Particulate Organic Carbon and Particulate Nitrogen; Dataset: Photosynthetic Pigments; Dataset: Physical Profiles of Temperature, Salinity, and Brine Volume; Sea-ice diatom compatible solute shifts", "datasets": [{"dataset_uid": "200378", "doi": "10.26008/1912/bco-dmo.913655.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Physical Profiles of Temperature, Salinity, and Brine Volume", "url": "https://www.bco-dmo.org/dataset/913655"}, {"dataset_uid": "200376", "doi": "10.26008/1912/bco-dmo.913566.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Particulate Organic Carbon and Particulate Nitrogen", "url": "https://www.bco-dmo.org/dataset/913566"}, {"dataset_uid": "200377", "doi": "10.26008/1912/bco-dmo.913222.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Photosynthetic Pigments", "url": "https://www.bco-dmo.org/dataset/913222"}, {"dataset_uid": "200322", "doi": "10.21228/M84386", "keywords": null, "people": null, "repository": "Metabolomics workbench", "science_program": null, "title": "Sea-ice diatom compatible solute shifts", "url": "https://www.metabolomicsworkbench.org/data/DRCCMetadata.php?Mode=Study\u0026StudyID=ST001393"}], "date_created": "Tue, 23 Jul 2019 00:00:00 GMT", "description": "Rapid changes in the extent and thickness of sea ice during the austral spring subject microorganisms within or attached to the ice to large fluctuations in temperature, salinity, light and nutrients. This project aims to identify cellular responses in sea-ice algae to increasing temperature and decreasing salinity during the spring melt along the western Antarctic Peninsula and to determine how associated changes at the cellular level can potentially affect dynamic, biologically driven processes. Understanding how sea-ice algae cope with, and are adapted to, their environment will not only help predict how polar ecosystems may change as the extent and thickness of sea ice change, but will also provide a better understanding of the widespread success of photosynthetic life on Earth. The scientific context and resulting advances from the research will be communicated to the general public through outreach activities that includes work with Science Communication Fellows and the popular Polar Science Weekend at the Pacific Science Center in Seattle, Washington. The project will provide student training to college students as well as provide for educational experiences for K-12 school children. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eThere is currently a poor understanding of feedback relationships that exist between the rapidly changing environment in the western Antarctic Peninsula region and sea-ice algal production. The large shifts in temperature and salinity that algae experience during the spring melt affect critical cellular processes, including rates of enzyme-catalyzed reactions involved in photosynthesis and respiration, and the production of stress-protective compounds. These changes in cellular processes are poorly constrained but can be large and may have impacts on local ecosystem productivity and biogeochemical cycles. In particular, this study will focus on the thermal sensitivity of enzymes and the cycling of compatible solutes and exopolymers used for halo- and cryo-protection, and how they influence primary production and the biogeochemical cycling of carbon and nitrogen. Approaches will include field sampling during spring melt, incubation experiments of natural sea-ice communities under variable temperature and salinity conditions, and controlled manipulation of sea-ice algal species in laboratory culture. Employment of a range of techniques, from fast repetition rate fluorometry and gross and net photosynthetic measurements to metabolomics and enzyme kinetics, will tease apart the mechanistic effects of temperature and salinity on cell metabolism and primary production with the goal of quantifying how these changes will impact biogeochemical processes along the western Antarctic Peninsula.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -64.2, "geometry": "POINT(-64.3 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; SHIPS; DIATOMS; Antarctic Peninsula", "locations": "Antarctic Peninsula", "north": -64.2, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Young, Jodi; Deming, Jody", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "BCO-DMO", "repositories": "BCO-DMO; Metabolomics workbench", "science_programs": null, "south": -64.8, "title": "Spring Blooms of Sea Ice Algae Along the Western Antarctic Peninsula: Effects of Warming and Freshening on Cell Physiology and Biogeochemical Cycles.", "uid": "p0010039", "west": -64.4}, {"awards": "1543229 Severinghaus, Jeffrey; 1543267 Brook, Edward J.", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Multi-site ice core Krypton stable isotope ratios; Noble Gas Data from recent ice in Antarctica for 86Kr problem", "datasets": [{"dataset_uid": "601394", "doi": "10.15784/601394", "keywords": "Antarctica; Bruce Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland Ice Cap; Ice Core; Ice Core Chemistry; Ice Core Records; James Ross Island; Krypton; Law Dome; Low Dome Ice Core; Roosevelt Island; Siple Dome; Siple Dome Ice Core; South Pole; SPICEcore; WAIS Divide; WAIS Divide Ice Core", "people": "Brook, Edward J.; Severinghaus, Jeffrey P.; Bereiter, Bernhard; Shackleton, Sarah; Etheridge, David; Mosley-Thompson, Ellen; Mulvaney, Robert; Buizert, Christo; Pyne, Rebecca L.; Baggenstos, Daniel; Bertler, Nancy", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Multi-site ice core Krypton stable isotope ratios", "url": "https://www.usap-dc.org/view/dataset/601394"}, {"dataset_uid": "601195", "doi": "10.15784/601195", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Krypton; Noble Gas; Xenon", "people": "Shackleton, Sarah; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Noble Gas Data from recent ice in Antarctica for 86Kr problem", "url": "https://www.usap-dc.org/view/dataset/601195"}, {"dataset_uid": "601394", "doi": "10.15784/601394", "keywords": "Antarctica; Bruce Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland Ice Cap; Ice Core; Ice Core Chemistry; Ice Core Records; James Ross Island; Krypton; Law Dome; Low Dome Ice Core; Roosevelt Island; Siple Dome; Siple Dome Ice Core; South Pole; SPICEcore; WAIS Divide; WAIS Divide Ice Core", "people": "Buizert, Christo; Mosley-Thompson, Ellen; Mulvaney, Robert; Pyne, Rebecca L.; Bertler, Nancy; Etheridge, David; Bereiter, Bernhard; Baggenstos, Daniel; Brook, Edward J.; Severinghaus, Jeffrey P.; Shackleton, Sarah", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Multi-site ice core Krypton stable isotope ratios", "url": "https://www.usap-dc.org/view/dataset/601394"}, {"dataset_uid": "601394", "doi": "10.15784/601394", "keywords": "Antarctica; Bruce Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland Ice Cap; Ice Core; Ice Core Chemistry; Ice Core Records; James Ross Island; Krypton; Law Dome; Low Dome Ice Core; Roosevelt Island; Siple Dome; Siple Dome Ice Core; South Pole; SPICEcore; WAIS Divide; WAIS Divide Ice Core", "people": "Brook, Edward J.; Baggenstos, Daniel; Bereiter, Bernhard; Shackleton, Sarah; Etheridge, David; Bertler, Nancy; Pyne, Rebecca L.; Mulvaney, Robert; Mosley-Thompson, Ellen; Buizert, Christo; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Multi-site ice core Krypton stable isotope ratios", "url": "https://www.usap-dc.org/view/dataset/601394"}], "date_created": "Wed, 10 Jul 2019 00:00:00 GMT", "description": "Overview: The funded work investigated whether ice core 86Kr acts as a proxy for barometric pressure variability, and whether this proxy can be used in Antarctic ice cores to infer past movement of the Southern Hemisphere (SH) westerly winds. Pressure variations drive macroscopic air movement in the firn column, which reduces the gravitational isotopic enrichment of slow-diffusing gases (such as Kr). The 86Kr deviation from gravitational equilibrium (denoted D86Kr) thus reflects the magnitude of pressure variations (among other things). Atmospheric reanalysis data suggest that pressure variability over Antarctica is linked to the Southern Annular Mode (SAM) index and the position of the SH westerly winds. Preliminary data from the WAIS Divide ice core show a large excursion in D86Kr during the last deglaciation (20-9 ka before present). In this project the investigators (1) performed high-precision 86Kr analysis on ice core and firn air samples to establish whether D86Kr is linked to pressure variability; (2) Refined the deglacial WAIS Divide record of Kr isotopes; (3) Investigated the role of pressure variability in firn air transport using firn air models with firn microtomography data and Lattice- Boltzmann modeling; and (4) Investigated how barometric pressure variability in Antarctica is linked to the SAM index and the position/strength of the SH westerlies in past and present climates using GCM and reanalysis data. A key finding was that D86Kr in recent ice samples (e.g. last 50 years) from a broad spatial array of sites in Antarctica and Greenland showed a significant correlation with directly measured barometric pressure variability at the ice core site. This strongly supports the hypothesis that 86Kr can be used as a paleo-proxy for storminess.\r\nIntellectual Merit: The SH westerlies are a key component of the global climate system; they are an important control on the global oceanic overturning circulation and possibly on atmospheric CO2 concentrations. Poleward movement of the SH westerlies during the last deglaciation has been hypothesized, yet evidence from proxy and modeling studies remains inconclusive. The funded work could provide valuable new constraints on deglacial movement of the SH westerlies. This record can be compared to high-resolution CO2 data from the same core, allowing us to test hypotheses that link CO2 to the SH westerlies. Climate proxies are at the heart of paleoclimate research. The funded work has apparently led to the discovery of a completely new proxy, opening up exciting new research possibilities and increasing the scientific value of existing ice cores. Once validated, the 86Kr proxy could be applied to other time periods as well, providing a long-term perspective on the movement of the SH westerlies. The funded work has furthermore provided valuable new insights into firn air transport. \r\n\r\nBroader impact: The Southern Ocean is presently an important sink of atmospheric CO2, thereby reducing the warming associated with anthropogenic CO2 emissions. Stratospheric ozone depletion and greenhouse warming have displaced the SH westerlies poleward, with potential consequences for the future magnitude of this oceanic carbon uptake. The funded work may provide a paleo-perspective on past movement of the SH westerlies and its link to atmospheric CO2, which could guide projections of future oceanic CO2 uptake, with strong societal benefits. The awarded funds supported and trained an early-career postdoctoral scholar at OSU, and fostered (international) collaboration. Data from the study will be available to the scientific community and the broad public through recognized data centers. During this project the PI and senior personnel have continued their commitment to public outreach through media interviews and speaking to schools and the public about their work. The PI provides services to the community by chairing the IPICS (International Partnership in Ice Core Sciences) working group and organizing annual PIRE (Partnerships in International Research and Education) workshops.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USA/NSF; FIRN; ICE CORE RECORDS; USAP-DC; Greenland; Xenon; Noble Gas; Ice Core; Amd/Us; Antarctica; AMD; LABORATORY; Krypton; ATMOSPHERIC PRESSURE", "locations": "Greenland; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.; Brook, Edward J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative research: Kr-86 as a proxy for barometric pressure variability and movement of the SH westerlies during the last\r\ndeglaciation", "uid": "p0010037", "west": -180.0}, {"awards": "1443677 Padman, Laurence; 1443498 Fricker, Helen; 1443497 Siddoway, Christine; 1443534 Bell, Robin", "bounds_geometry": "POLYGON((-180 -77,-177 -77,-174 -77,-171 -77,-168 -77,-165 -77,-162 -77,-159 -77,-156 -77,-153 -77,-150 -77,-150 -77.9,-150 -78.8,-150 -79.7,-150 -80.6,-150 -81.5,-150 -82.4,-150 -83.3,-150 -84.2,-150 -85.1,-150 -86,-153 -86,-156 -86,-159 -86,-162 -86,-165 -86,-168 -86,-171 -86,-174 -86,-177 -86,180 -86,178.1 -86,176.2 -86,174.3 -86,172.4 -86,170.5 -86,168.6 -86,166.7 -86,164.8 -86,162.9 -86,161 -86,161 -85.1,161 -84.2,161 -83.3,161 -82.4,161 -81.5,161 -80.6,161 -79.7,161 -78.8,161 -77.9,161 -77,162.9 -77,164.8 -77,166.7 -77,168.6 -77,170.5 -77,172.4 -77,174.3 -77,176.2 -77,178.1 -77,-180 -77))", "dataset_titles": "Basal Melt, Ice thickness and structure of the Ross Ice Shelf using airborne radar data; CATS2008: Circum-Antarctic Tidal Simulation version 2008; CATS2008_v2023: Circum-Antarctic Tidal Simulation 2008, version 2023; Deep ICE (DICE) Radar Dataset from Ross Ice Shelf (ROSETTA-Ice); LiDAR Nadir and Swath Data from Ross Ice Shelf, Antarctica (ROSETTA-Ice); ROSETTA-Ice data page; Ross Sea ocean model simulation used to support ROSETTA-Ice ; Shallow Ice Radar (SIR) Dataset from Ross Ice Shelf (ROSETTA-Ice)", "datasets": [{"dataset_uid": "601242", "doi": "10.15784/601242", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Penetrating Radar; Ice-Shelf Basal Melting; Radar Echo Sounder; Radar Echo Sounding; Snow/ice; Snow/Ice", "people": "Bell, Robin; Fricker, Helen; Hulbe, Christina; Siddoway, Christine; Dhakal, Tejendra; Frearson, Nicholas; Mosbeux, Cyrille; Cordero, Isabel; Das, Indrani; Siegfried, Matt; Padman, Laurence; Tinto, Kirsty", "repository": "USAP-DC", "science_program": null, "title": "Basal Melt, Ice thickness and structure of the Ross Ice Shelf using airborne radar data", "url": "https://www.usap-dc.org/view/dataset/601242"}, {"dataset_uid": "601794", "doi": null, "keywords": "Antarctica; Cryosphere; Remote Sensing; Ross Ice Shelf", "people": "Das, Indrani; Dong, LingLing; Packard, Sarah; Spergel, Julian; Wearing, Martin; Bell, Robin; Chu, Winnie; Cordero, Isabel; Frearson, Nicholas; Dhakal, Tejendra; Bertinato, Christopher; Keeshin, Skye", "repository": "USAP-DC", "science_program": null, "title": "Shallow Ice Radar (SIR) Dataset from Ross Ice Shelf (ROSETTA-Ice)", "url": "https://www.usap-dc.org/view/dataset/601794"}, {"dataset_uid": "601788", "doi": null, "keywords": "Antarctica; Cryosphere; Ross Ice Shelf", "people": "Dhakal, Tejendra; Bertinato, Christopher; Locke, Caitlin; Boghosian, Alexandra; Starke, Sarah; Becker, Maya K", "repository": "USAP-DC", "science_program": null, "title": "LiDAR Nadir and Swath Data from Ross Ice Shelf, Antarctica (ROSETTA-Ice)", "url": "https://www.usap-dc.org/view/dataset/601788"}, {"dataset_uid": "601772", "doi": "10.15784/601772", "keywords": "Antarctica; Cryosphere; Inverse Modeling; Model Data; Ocean Currents; Oceans; Sea Surface; Southern Ocean; Tide Model; Tides", "people": "Padman, Laurence; Sutterley, Tyler; Howard, Susan L.; Greene, Chad A.; Erofeeva, Svetlana", "repository": "USAP-DC", "science_program": null, "title": "CATS2008_v2023: Circum-Antarctic Tidal Simulation 2008, version 2023", "url": "https://www.usap-dc.org/view/dataset/601772"}, {"dataset_uid": "200100", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "ROSETTA-Ice data page", "url": "http://wonder.ldeo.columbia.edu/data/ROSETTA-Ice/"}, {"dataset_uid": "601789", "doi": null, "keywords": "Airborne Radar; Antarctica; Cryosphere; Ice Thickness; Remote Sensing; Ross Ice Shelf", "people": "Wilner, Joel; Millstein, Joanna; Bertinato, Christopher; Dhakal, Tejendra; Frearson, Nicholas; Cordero, Isabel; Chu, Winnie; Bell, Robin; Spergel, Julian; Das, Indrani; Dong, LingLing", "repository": "USAP-DC", "science_program": null, "title": "Deep ICE (DICE) Radar Dataset from Ross Ice Shelf (ROSETTA-Ice)", "url": "https://www.usap-dc.org/view/dataset/601789"}, {"dataset_uid": "601235", "doi": "10.15784/601235", "keywords": "Antarctica; Inverse Modeling; Model Data; Ocean Currents; Sea Surface; Tidal Models; Tides", "people": "Howard, Susan L.; Padman, Laurence; Erofeeva, Svetlana", "repository": "USAP-DC", "science_program": null, "title": "CATS2008: Circum-Antarctic Tidal Simulation version 2008", "url": "https://www.usap-dc.org/view/dataset/601235"}, {"dataset_uid": "601255", "doi": "10.15784/601255", "keywords": "Antarctica; Basal Melt; Ice Shelf; Model Output; Ocean Circulation Model; Ross Ice Shelf; Ross Sea", "people": "Howard, Susan L.; Padman, Laurence; Springer, Scott", "repository": "USAP-DC", "science_program": null, "title": "Ross Sea ocean model simulation used to support ROSETTA-Ice ", "url": "https://www.usap-dc.org/view/dataset/601255"}], "date_created": "Wed, 03 Jul 2019 00:00:00 GMT", "description": "The Ross Ice Shelf is the largest existing ice shelf in Antarctica, and is currently stabilizing significant portions of the land ice atop the Antarctic continent. An ice shelf begins where the land ice goes afloat on the ocean, and as such, the Ross Ice Shelf interacts with the ocean and seafloor below, and the land ice behind. Currently, the Ross Ice Shelf slows down, or buttresses, the fast flowing ice streams of the West Antarctic Ice Sheet (WAIS), a marine-based ice sheet, which if melted, would raise global sea level by 3-4 meters. The Ross Ice Shelf average ice thickness is approximately 350 meters, and it covers approximately 487,000 square kilometers, an area slightly larger than the state of California. The Ross Ice Shelf has disappeared during prior interglacial periods, suggesting in the future it may disappear again. Understanding the dynamics, stability and future of the West Antarctic Ice Sheet therefore requires in-depth knowledge of the Ross Ice Shelf. The ROSETTA-ICE project brings together scientists from 4 US institutions and from the Institute of Geological and Nuclear Sciences Limited, known as GNS Science, New Zealand. The ROSETTA-ICE data on the ice shelf, the water beneath the ice shelf, and the underlying rocks, will allow better predictions of how the Ross Ice Shelf will respond to changing climate, and therefore how the WAIS will behave in the future. The interdisciplinary ROSETTA-ICE team will train undergraduate and high school students in cutting edge research techniques, and will also work to educate the public via a series of vignettes integrating ROSETTA-ICE science with the scientific and human history of Antarctic research.\u003cbr/\u003e\u003cbr/\u003eThe ROSETTA-ICE survey will acquire gravity and magnetics data to determine the water depth beneath the ice shelf. Radar, LIDAR and imagery systems will be used to map the Ross Ice Shelf thickness and fine structure, crevasses, channels, debris, surface accumulation and distribution of marine ice. The high resolution aerogeophysical data over the Ross Ice Shelf region in Antarctica will be acquired using the IcePod sensor suite mounted externally on an LC-130 aircraft operating from McMurdo Station, Antarctica. Field activities will include ~36 flights on LC-130 aircraft over two field seasons in Antarctica. The IcePod instrument suite leverages the unique experience of the New York Air National Guard operating in Antarctica for NSF scientific research as well as infrastructure and logistics. The project will answer questions about the stability of the Ross Ice Shelf in future climate, and the geotectonic evolution of the Ross Ice Shelf Region, a key component of the West Antarctic Rift system. The comprehensive benchmark data sets acquired will enable broad, interdisciplinary analyses and modeling, which will also be performed as part of the project. ROSETTA-ICE will illuminate Ross ice sheet-ice shelf-ocean dynamics as the system nears a critical juncture but still is intact. Through interacting with an online data visualization tool, and comparing the ROSETTA-ICE data and results from earlier studies, we will engage students and young investigators, equipping them with new capabilities for the study of critical earth systems that influence global climate.", "east": 161.0, "geometry": "POINT(-174.5 -81.5)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LIDAR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e MAGNETIC FIELD/ELECTRIC FIELD INSTRUMENTS \u003e PROTON MAGNETOMETER", "is_usap_dc": true, "keywords": "Airborne Radar; LIDAR; Ross Ice Shelf; SALINITY; SALINITY/DENSITY; CONDUCTIVITY; ICE DEPTH/THICKNESS; Tidal Models; GRAVITY ANOMALIES; Ross Sea; Antarctica; BATHYMETRY; C-130; MAGNETIC ANOMALIES; USAP-DC; Airborne Gravity", "locations": "Ross Sea; Antarctica; Ross Ice Shelf", "north": -77.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Bell, Robin; Frearson, Nicholas; Das, Indrani; Fricker, Helen; Padman, Laurence; Springer, Scott; Siddoway, Christine; Tinto, Kirsty", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e C-130", "repo": "USAP-DC", "repositories": "PI website; USAP-DC", "science_programs": null, "south": -86.0, "title": "Collaborative Research: Uncovering the Ross Ocean and Ice Shelf Environment and Tectonic setting Through Aerogeophysical Surveys and Modeling (ROSETTA-ICE)", "uid": "p0010035", "west": -150.0}, {"awards": "1341513 Maksym, Edward; 1341725 Guest, Peter; 1341717 Ackley, Stephen; 1341606 Stammerjohn, Sharon; 1543483 Sedwick, Peter", "bounds_geometry": "POLYGON((-180 -55,-177 -55,-174 -55,-171 -55,-168 -55,-165 -55,-162 -55,-159 -55,-156 -55,-153 -55,-150 -55,-150 -57.3,-150 -59.6,-150 -61.9,-150 -64.2,-150 -66.5,-150 -68.8,-150 -71.1,-150 -73.4,-150 -75.7,-150 -78,-153 -78,-156 -78,-159 -78,-162 -78,-165 -78,-168 -78,-171 -78,-174 -78,-177 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -75.7,160 -73.4,160 -71.1,160 -68.8,160 -66.5,160 -64.2,160 -61.9,160 -59.6,160 -57.3,160 -55,162 -55,164 -55,166 -55,168 -55,170 -55,172 -55,174 -55,176 -55,178 -55,-180 -55))", "dataset_titles": "ASPeCt Visual Ice Observations on PIPERS Cruise NBP1704 April-June 2017; Expedition data of NBP1704; Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle; NBP1704 CTD sensor data; NBP1704 Expedition Data; PIPERS Airborne LiDAR Data; PIPERS Meteorology Rawinsonde Data; PIPERS Meteorology Time Series; PIPERS Noble Gases; Sea Ice Layer Cakes, PIPERS 2017; SUMO unmanned aerial system (UAS) atmospheric data", "datasets": [{"dataset_uid": "002663", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1704", "url": "https://www.rvdata.us/search/cruise/NBP1704"}, {"dataset_uid": "601184", "doi": "10.15784/601184 ", "keywords": "Air Temperature; Antarctica; Atmosphere; Meteorology; Near-Surface Air Temperatures; PIPERS; Radiation; Sea Ice Temperatures; Temperature; Weather Station Data; Wind Direction; Wind Speed", "people": "Guest, Peter", "repository": "USAP-DC", "science_program": null, "title": "PIPERS Meteorology Time Series", "url": "https://www.usap-dc.org/view/dataset/601184"}, {"dataset_uid": "200150", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle", "url": "https://www.bco-dmo.org/project/815403"}, {"dataset_uid": "601207", "doi": "10.15784/601207", "keywords": "Antarctica; Digital Elevation Model; Glaciology; Ice; Ice Thickness; Ice Thickness Distribution; LIDAR; NBP1704; PIPERS; Ross Sea; R/v Nathaniel B. Palmer; Sea Ice; Snow; Snow Depth; Surface Elevation", "people": "Jeffrey Mei, M.; Mei, M. Jeffrey; Maksym, Edward", "repository": "USAP-DC", "science_program": null, "title": "Sea Ice Layer Cakes, PIPERS 2017", "url": "https://www.usap-dc.org/view/dataset/601207"}, {"dataset_uid": "601422", "doi": "10.15784/601422", "keywords": "Antarctica; CTD; CTD Data; NBP1704; Ocean Profile Data; Ross Sea; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Stammerjohn, Sharon", "repository": "USAP-DC", "science_program": null, "title": "NBP1704 CTD sensor data", "url": "https://www.usap-dc.org/view/dataset/601422"}, {"dataset_uid": "601185", "doi": "10.15784/601185 ", "keywords": "Air Temperature; Antarctica; Atmosphere; Atmospheric Surface Winds; Meteorology; NBP1704; PIPERS; Pressure; Radiosonde; Rawinsonde; Relative Humidity; Ross Sea; R/v Nathaniel B. Palmer; Wind Direction; Wind Speed", "people": "Guest, Peter", "repository": "USAP-DC", "science_program": null, "title": "PIPERS Meteorology Rawinsonde Data", "url": "https://www.usap-dc.org/view/dataset/601185"}, {"dataset_uid": "601188", "doi": "10.15784/601188", "keywords": "Aerogeophysics; Airborne Laser Altimetry; Antarctica; LIDAR; PIPERS; Ross Sea; Sea Ice", "people": "Bell, Robin; Bertinato, Christopher; Xie, Hongjie; Dhakal, Tejendra; Locke, Caitlin", "repository": "USAP-DC", "science_program": null, "title": "PIPERS Airborne LiDAR Data", "url": "https://www.usap-dc.org/view/dataset/601188"}, {"dataset_uid": "001363", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1704 Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1704"}, {"dataset_uid": "601191", "doi": "10.15784/601191", "keywords": "Air Temperature; Antarctica; Atmosphere; Meteorology; NBP1704; PIPERS; R/v Nathaniel B. Palmer; Southern Ocean; Temperature Profiles; UAV; Unmanned Aircraft", "people": "Cassano, John", "repository": "USAP-DC", "science_program": null, "title": "SUMO unmanned aerial system (UAS) atmospheric data", "url": "https://www.usap-dc.org/view/dataset/601191"}, {"dataset_uid": "601183", "doi": "10.15784/601183", "keywords": "Antarctica; Glaciology; Ice Concentration; Ice Thickness; Ice Type; NBP1704; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Sea Ice; Snow Depth; Snow/ice; Snow/Ice; Visual Observations", "people": "Ackley, Stephen", "repository": "USAP-DC", "science_program": null, "title": "ASPeCt Visual Ice Observations on PIPERS Cruise NBP1704 April-June 2017", "url": "https://www.usap-dc.org/view/dataset/601183"}, {"dataset_uid": "601609", "doi": "10.15784/601609", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Mass Spectrometer; NBP1704; Noble Gas; Oceans; Ross Sea; R/v Nathaniel B. Palmer", "people": "Loose, Brice", "repository": "USAP-DC", "science_program": null, "title": "PIPERS Noble Gases", "url": "https://www.usap-dc.org/view/dataset/601609"}], "date_created": "Mon, 10 Jun 2019 00:00:00 GMT", "description": "The one place on Earth consistently showing increases in sea ice area, duration, and concentration is the Ross Sea in Antarctica. Satellite imagery shows about half of the Ross Sea increases are associated with changes in the austral fall, when the new sea ice is forming. The most pronounced changes are also located near polynyas, which are areas of open ocean surrounded by sea ice. To understand the processes driving the sea ice increase, and to determine if the increase in sea ice area is also accompanied by a change in ice thickness, this project will conduct an oceanographic cruise to the polynyas of the Ross Sea in April and May, 2017, which is the austral fall. The team will deploy state of the art research tools including unmanned airborne systems (UASs, commonly called drones), autonomous underwater vehicles (AUVs), and remotely operated underwater vehicles (ROVs). Using these tools and others, the team will study atmospheric, oceanic, and sea ice properties and processes concurrently. A change in sea ice production will necessarily change the ocean water below, which may have significant consequences for global ocean circulation patterns, a topic of international importance. All the involved institutions will be training students, and all share the goal of expanding climate literacy in the US, emphasizing the role high latitudes play in the Earth\u0027s dynamic climate.\u003cbr/\u003e\u003cbr/\u003eThe main goal of the project is to improve estimates of sea ice production and water mass transformation in the Ross Sea. The team will fully capture the spatial and temporal changes in air-ice-ocean interactions when they are initiated in the austral fall, and then track the changes into the winter and spring using ice buoys, and airborne mapping with the newly commissioned IcePod instrument system, which is deployed on the US Antarctic Program\u0027s LC-130 fleet. The oceanographic cruise will include stations in and outside of both the Terra Nova Bay and Ross Ice Shelf polynyas. Measurements to be made include air-sea boundary layer fluxes of heat, freshwater, and trace gases, radiation, and meteorology in the air; ice formation processes, ice thickness, snow depth, mass balance, and ice drift within the sea ice zone; and temperature, salinity, and momentum in the ocean below. Following collection of the field data, the team will improve both model parameterizations of air-sea-ice interactions and remote sensing algorithms. Model parameterizations are needed to determine if sea-ice production has increased in crucial areas, and if so, why (e.g., stronger winds or fresher oceans). The remote sensing validation will facilitate change detection over wider areas and verify model predictions over time. Accordingly this project will contribute to the international Southern Ocean Observing System (SOOS) goal of measuring essential climate variables continuously to monitor the state of the ocean and ice cover into the future.", "east": -150.0, "geometry": "POINT(-175 -66.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LIDAR; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "OCEAN MIXED LAYER; TRACE ELEMENTS; CARBON DIOXIDE; ATMOSPHERIC RADIATION; ICE GROWTH/MELT; AMD; BOUNDARY LAYER TEMPERATURE; SULFUR COMPOUNDS; NBP1704; HEAT FLUX; ICE DEPTH/THICKNESS; R/V NBP; USA/NSF; BOUNDARY LAYER WINDS; SNOW DEPTH; VERTICAL PROFILES; METHANE; POLYNYAS; CONDUCTIVITY; SEA ICE; Ross Sea; WATER MASSES; TURBULENCE; USAP-DC; Amd/Us", "locations": "Ross Sea", "north": -55.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Instrumentation and Support; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Ackley, Stephen; Bell, Robin; Weissling, Blake; Nuss, Wendell; Maksym, Edward; Stammerjohn, Sharon; Cassano, John; Guest, Peter; Sedwick, Peter; Xie, Hongjie", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "BCO-DMO; R2R; USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Seasonal Sea Ice Production in the Ross Sea, Antarctica", "uid": "p0010032", "west": 160.0}, {"awards": "1246357 Bart, Philip", "bounds_geometry": null, "dataset_titles": "NBP1502 Cruise Geophysics and underway data; NBP1502 YoYo camera benthic images from Ross Sea", "datasets": [{"dataset_uid": "000245", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1502 Cruise Geophysics and underway data", "url": "https://www.rvdata.us/search/cruise/NBP1502"}, {"dataset_uid": "601182", "doi": "10.15784/601182", "keywords": "Antarctica; Benthic; Benthic Images; Benthos; Bentic Fauna; Camera Tow; Marine Geoscience; Marine Sediments; NBP1502; Photo; Photo/video; Photo/Video; Ross Sea; R/v Nathaniel B. Palmer; Southern Ocean; Yoyo Camera", "people": "Bart, Philip", "repository": "USAP-DC", "science_program": null, "title": "NBP1502 YoYo camera benthic images from Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601182"}], "date_created": "Mon, 03 Jun 2019 00:00:00 GMT", "description": "Intellectual Merit:\n\nEvidence from the eastern Ross Sea continental shelf indicates that the West Antarctic Ice Sheet advanced and retreated during the last glacial cycle, but it is unclear whether the ice sheet advanced to the shelf edge or just to the middle shelf. These two end-member scenarios offer different interpretations as to why, how, and when the West Antarctic Ice Sheet oscillated. The PI proposes to acquire seismic, multibeam, and core data from Whales Deep, to evaluate the timing and duration of two advances of grounded ice to the outer and middle shelf of the Whales Deep Basin, a West Antarctic Ice Sheet paleo ice stream trough in eastern Ross Sea. Grounding events are represented by seismically resolvable Grounding Zone Wedges. The PI will collect radiocarbon dates on in situ benthic foraminifera from the grounding zone diamict as well as ramped pyrolysis radiocarbon dates on acid insoluble organics from open-marine mud overlying the grounding zone diamict. Using these data the PI will calculate the duration of the two grounding events. Furthermore, the PI will test a numerical model prediction that West Antarctic Ice Sheet retreat must have involved melting at the marine terminus of the ice sheet. Pore-water from the grounding zone diamict will be extracted from piston cores to determine salinity and \u03b418O values that should indicate if significant melting occurred at the grounding line.\n\nBroader impacts:\n\nThe data collected will provide constraints on the timing and pattern of Last Glacial Maximum advance and retreat that can be incorporated into interpretations of ice-surface elevation changes. The proposed activities will provide valuable field and research training to undergraduate/graduate students and a Louisiana high-school science teacher. The research will be interactively shared with middle- and high-school science students and with visitors to the LSU Museum of Natural Science Weekend-Science Program. ", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e AIRGUN ARRAYS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e SEISMIC REFLECTION PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e LONG STREAMERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERA; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "STRATIGRAPHIC SEQUENCE; R/V NBP; Ross Sea; Antarctica; MICROFOSSILS; RADIOCARBON; PALEOCLIMATE RECONSTRUCTIONS; SEDIMENTS; Southern Ocean; OCEANS; GEOSCIENTIFIC INFORMATION", "locations": "Antarctica; Ross Sea; Southern Ocean", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Bart, Philip; Steinberg, Deborah", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Timing and Duration of the LGM and Post-LGM Grounding Events in Whales Deep Paleo Ice Stream, Eastern Ross Sea Middle Continental Shelf", "uid": "p0000877", "west": null}, {"awards": "1637708 Gooseff, Michael", "bounds_geometry": "POLYGON((160 -77.25,160.5 -77.25,161 -77.25,161.5 -77.25,162 -77.25,162.5 -77.25,163 -77.25,163.5 -77.25,164 -77.25,164.5 -77.25,165 -77.25,165 -77.375,165 -77.5,165 -77.625,165 -77.75,165 -77.875,165 -78,165 -78.125,165 -78.25,165 -78.375,165 -78.5,164.5 -78.5,164 -78.5,163.5 -78.5,163 -78.5,162.5 -78.5,162 -78.5,161.5 -78.5,161 -78.5,160.5 -78.5,160 -78.5,160 -78.375,160 -78.25,160 -78.125,160 -78,160 -77.875,160 -77.75,160 -77.625,160 -77.5,160 -77.375,160 -77.25))", "dataset_titles": "EDI Data Portal: McMurdo Dry Valleys LTER; McMurdo Dry Valleys LTER Data Repository", "datasets": [{"dataset_uid": "200037", "doi": "", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "EDI Data Portal: McMurdo Dry Valleys LTER", "url": "https://portal.edirepository.org/nis/browseServlet?searchValue=MCM"}, {"dataset_uid": "200036", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "McMurdo Dry Valleys LTER Data Repository", "url": "http://mcm.lternet.edu/power-search/data-set"}], "date_created": "Fri, 31 May 2019 00:00:00 GMT", "description": "The McMurdo Dry Valleys, Antarctica, are a mosaic of terrestrial and aquatic ecosystems in a cold desert. The McMurdo Long Term Ecological Research (LTER) project has been observing these ecosystems since 1993 and this award will support key long-term measurements, manipulation experiments, synthesis, and modeling to test current theories on ecosystem structure and function. Data collection is focused on meteorology and physical and biological dimensions of soils, streams, lakes, glaciers, and permafrost. The long-term measurements show that biological communities have adapted to the seasonally cold, dark, and arid conditions that prevail for all but a short period in the austral summer. Physical (climate and geological) drivers impart a dynamic connectivity among portions of the Dry Valley landscape over seasonal to millennial time scales. For instance, lakes and soils have been connected through cycles of lake-level rise and fall over the past 20,000 years while streams connect glaciers to lakes over seasonal time scales. Overlaid upon this physical system are biotic communities that are structured by the environment and by the movement of individual organisms within and between the glaciers, streams, lakes, and soils. The new work to be conducted at the McMurdo LTER site will explore how the layers of connectivity in the McMurdo Dry Valleys influence ecosystem structure and function. \r\n\r\nThis project will test the hypothesis that increased ecological connectivity following enhanced melt conditions within the McMurdo Dry Valleys ecosystem will amplify exchange of biota, energy, and matter, homogenizing ecosystem structure and functioning. This hypothesis will be tested with new and continuing experiments that examine: 1) how climate variation alters connectivity among landscape units, and 2) how biota are connected across a heterogeneous landscape using state-of-the-science tools and methods including automated sensor networks, analysis of seasonal satellite imagery, biogeochemical analyses, and next-generation sequencing. McMurdo LTER education programs and outreach activities will be continued, and expanded with new programs associated with the 200th anniversary of the first recorded sightings of Antarctica. These activities will advance societal understanding of how polar ecosystems respond to change. McMurdo LTER will continue its mission of training and mentoring students, postdocs, and early career scientists as the next generation of leaders in polar ecosystem science, and lead the development of international environmental stewardship protocols for human activities in the region.", "east": 165.0, "geometry": "POINT(162.5 -77.875)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; NOT APPLICABLE; Antarctica; RIVERS/STREAM; USAP-DC; TERRESTRIAL ECOSYSTEMS; LAKE/POND; Polar", "locations": "Antarctica; Polar", "north": -77.25, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Gooseff, Michael N.; Takacs-Vesbach, Cristina; Howkins, Adrian; McKnight, Diane; Doran, Peter; Adams, Byron; Barrett, John; Morgan-Kiss, Rachael; Priscu, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "EDI", "repositories": "EDI; LTER", "science_programs": "LTER", "south": -78.5, "title": "LTER: Ecosystem Response to Amplified Landscape Connectivity in the McMurdo Dry Valleys, Antarctica", "uid": "p0010031", "west": 160.0}, {"awards": "1642570 Thurber, Andrew", "bounds_geometry": "POINT(166.666 -77.8)", "dataset_titles": "Microbial community composition of the Cinder Cones Cold Seep", "datasets": [{"dataset_uid": "200035", "doi": "DOI:10.1575/1912/bco-dmo.756997.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Microbial community composition of the Cinder Cones Cold Seep", "url": "https://www.bco-dmo.org/dataset/756997"}], "date_created": "Fri, 24 May 2019 00:00:00 GMT", "description": "Methane is a potent greenhouse gas that is naturally emitted into the oceans by geologic seeps and microbial production. Based on studies of persistent deep-sea seeps at mid- and northern latitudes, researchers have learned that bacteria and archaea can create a \"sediment filter\" that oxidizes methane prior to its release. Antarctica is thought to contain large reservoirs of organic carbon buried beneath its ice which could a quantity of methane equivalent to all of the permafrost in the Arctic and yet we know almost nothing about the methane oxidizing microbes in this region. How these microbial communities develop and potentially respond to fluctuations in methane levels is an under-explored avenue of research. A bacterial mat was recently discovered at 78 degrees south, suggesting the possible presence of a methane seep, and associated microbial communities. This project will explore this environment in detail to assess the levels and origin of methane, and the nature of the microbial ecosystem present. \u003cbr/\u003e \u003cbr/\u003eAn expansive bacterial mat appeared and/or was discovered at 78 degrees south in 2011. This site, near McMurdo Station Antarctica, has been visited since the mid-1960s, but this mat was not observed until 2011. The finding of this site provides an unusual opportunity to study an Antarctic marine benthic habitat with active methane cycling and to examine the dynamics of recruitment and community succession of seep fauna including bacteria, archaea, protists and metazoans. This project will collect the necessary baseline data to facilitate further studies of Antarctic methane cycling. The concentration and source of methane will be determined at this site and at potentially analogous sites in McMurdo Sound. In addition to biogeochemical characterization of the sites, molecular analysis of the microbial community will quantify the time scales on which bacteria and archaea respond to methane input and provide information on rates of community development and succession in the Southern Ocean. Project activities will facilitate the training of at least one graduate student and results will be shared at both local and international levels. A female graduate student will be mentored as part of this project and data collected will form part of her dissertation. Lectures will be given in K-12 classrooms in Oregon to excite students about polar science. National and international audiences will be reached through blogs and presentations at a scientific conference. The PI\u0027s previous blogs have been used by K-12 classrooms as part of their lesson plans and followed in over 65 countries.\u003cbr/\u003e", "east": 166.666, "geometry": "POINT(166.666 -77.8)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Sea Floor; USAP-DC; Ross Sea; BACTERIA/ARCHAEA; NOT APPLICABLE", "locations": "Ross Sea; Sea Floor", "north": -77.8, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Thurber, Andrew", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -77.8, "title": "EAGER: Elucidating the Antarctic Methane Cycle at the Cinder Cones Reducing Habitat.", "uid": "p0010030", "west": 166.666}, {"awards": "1544526 Omelon, Christopher", "bounds_geometry": "POLYGON((160 -76.5,160.37 -76.5,160.74 -76.5,161.11 -76.5,161.48 -76.5,161.85 -76.5,162.22 -76.5,162.59 -76.5,162.96 -76.5,163.33 -76.5,163.7 -76.5,163.7 -76.63,163.7 -76.76,163.7 -76.89,163.7 -77.02,163.7 -77.15,163.7 -77.28,163.7 -77.41,163.7 -77.54,163.7 -77.67,163.7 -77.8,163.33 -77.8,162.96 -77.8,162.59 -77.8,162.22 -77.8,161.85 -77.8,161.48 -77.8,161.11 -77.8,160.74 -77.8,160.37 -77.8,160 -77.8,160 -77.67,160 -77.54,160 -77.41,160 -77.28,160 -77.15,160 -77.02,160 -76.89,160 -76.76,160 -76.63,160 -76.5))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 09 May 2019 00:00:00 GMT", "description": "Cryptoendoliths are organisms that colonize microscopic cavities of rocks, which give them protection and allow them to inhabit extreme environments, such as the cold, arid desert of the Dry Valleys of Antarctica. Fossilized cryptoendoliths preserve the forms and features of organisms from the past and thus provide a unique opportunity to study the organisms\u0027 life histories and environments. To study this fossil record, there needs to be a better understanding of what environmental conditions allow these fossils to form. A climate gradient currently exists in the Dry Valleys that allows us to study living, dead, and fossilized cryptoendoliths from mild to increasingly harsh environments; providing insight to the limits of life and how these fossils are formed. This project will develop instruments to detect the biological activity of the live microorganisms and conduct laboratory experiments to determine the environmental limits of their survival. The project also will characterize the chemical and structural features of the living, dead, and fossilized cryptoendoliths to understand how they become fossilized. Knowing how microorganisms are preserved as fossils in cold and dry environments like Antarctica can help to refine methods that can be used to search for and identify evidence for extraterrestrial life in similar habitats on planets such as Mars. This project includes training of graduate and undergraduate students.\r\n\r\nLittle is known about cryptoendolithic microfossils and their formation processes in cold, arid terrestrial habitats of the Dry Valleys of Antarctica, where a legacy of activity is discernible in the form of biosignatures including inorganic materials and microbial fossils that preserve and indicate traces of past biological activity. The overarching goals of the proposed work are: (1) to determine how rates of microbial respiration and biodegradation of organic matter control microbial fossilization; and (2) to characterize microbial fossils and their living counterparts to elucidate mechanisms for fossilization. Using samples collected across an increasingly harsher (more cold and dry) climatic gradient that encompasses living, dead, and fossilized cryptoendolithic microorganisms, the proposed work will: (1) develop an instrument to be used in the field that can measure small concentrations of CO2 in cryptoendolithic habitats in situ; (2) use microscopy techniques to characterize endolithic microorganisms as well as the chemical and morphological characteristics of biosignatures and microbial fossils. A metagenomic survey of microbial communities in these samples will be used to characterize differences in diversity, identify if specific microorganisms (e.g. prokaryotes, eukaryotes) are more capable of surviving under these harsh climatic conditions, and to corroborate microscopic observations of the viability states of these microorganisms.", "east": 163.7, "geometry": "POINT(161.85 -77.15)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; Antarctica; NOT APPLICABLE; TERRESTRIAL ECOSYSTEMS", "locations": "Antarctica", "north": -76.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Omelon, Christopher; Breecker, Daniel; Bennett, Philip", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repositories": null, "science_programs": null, "south": -77.8, "title": "Activity, Preservation and Fossilization of Cryptoendolithic Microorganisms in Antarctica", "uid": "p0010028", "west": 160.0}, {"awards": "1443356 Conway, Howard; 1443552 Paul Winberry, J.", "bounds_geometry": "POLYGON((-175 -82.7,-173.9 -82.7,-172.8 -82.7,-171.7 -82.7,-170.6 -82.7,-169.5 -82.7,-168.4 -82.7,-167.3 -82.7,-166.2 -82.7,-165.1 -82.7,-164 -82.7,-164 -82.77,-164 -82.84,-164 -82.91,-164 -82.98,-164 -83.05,-164 -83.12,-164 -83.19,-164 -83.26,-164 -83.33,-164 -83.4,-165.1 -83.4,-166.2 -83.4,-167.3 -83.4,-168.4 -83.4,-169.5 -83.4,-170.6 -83.4,-171.7 -83.4,-172.8 -83.4,-173.9 -83.4,-175 -83.4,-175 -83.33,-175 -83.26,-175 -83.19,-175 -83.12,-175 -83.05,-175 -82.98,-175 -82.91,-175 -82.84,-175 -82.77,-175 -82.7))", "dataset_titles": "2015_Antarctica_Ground; Geophysical data from Crary Ice Rise, Ross Sea Embayment", "datasets": [{"dataset_uid": "601181", "doi": "10.15784/601181", "keywords": "Antarctica; Bed Elevation; Crary Ice Rise; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Ice Penetrating Radar; Ice Sheet Elevation; Ice Shelf; Ice Thickness; Internal Stratigraphy; Radar; Ross Ice Shelf; Snow/ice; Snow/Ice; Surface Elevation", "people": "Conway, Howard; Koutnik, Michelle; Paden, John; Winberry, Paul", "repository": "USAP-DC", "science_program": null, "title": "Geophysical data from Crary Ice Rise, Ross Sea Embayment", "url": "https://www.usap-dc.org/view/dataset/601181"}, {"dataset_uid": "200177", "doi": "", "keywords": null, "people": null, "repository": "CReSIS/ku.edu", "science_program": null, "title": "2015_Antarctica_Ground", "url": "https://data.cresis.ku.edu/data/accum/2015_Antarctica_Ground/"}], "date_created": "Mon, 06 May 2019 00:00:00 GMT", "description": "Recent observations and model results suggest that collapse of the Amundsen Sea sector of West Antarctica may already be underway. However, the timeline of collapse and the effects of ongoing climatic and oceanographic changes are key unanswered questions. Complete disintegration of the ice sheet would raise global sea level by more than 3 m, which would have significant societal impacts. Improved understanding of the controls on ice-sheet evolution is needed to make better predictions of ice-sheet behavior. Results from numerical models show that buttressing from surrounding ice shelves and/or from small-scale grounded ice rises should act to slow the retreat and discharge of ice from the interior ice sheet. However, there are very few field observations with which to develop and validate models. Field observations conducted in the early 1980s on Crary Ice Rise in the Ross Sea Embayment are a notable exception. This project will revisit Crary Ice Rise with new tools to make a suite of measurements designed to address questions about how the ice rise affects ice discharge from the Ross Sea sector of West Antarctica. The team will include a graduate and undergraduate student, and will participate in a range of outreach activities.\u003cbr/\u003e\u003cbr/\u003eNew tools including radar, seismic, and GPS instruments will be used to conduct targeted geophysical measurements both on Crary Ice Rise and across its grounding line. The project will use these new measurements, together with available ancillary data to inform a numerical model of grounding line dynamics. The model and measurements will be used to address the (1) How has the ice rise evolved over timescales ranging from: the past few decades; the past millennia after freeze-on; and through the deglaciation? (2) What history of ice dynamics is preserved in the radar-detected internal stratigraphy? (3) What dynamical effect does the presence/absence of the ice rise have on discharge of the Ross Ice Streams today? (4) How is it contributing to the slow-down of the proximal Whillans and Mercer ice streams? (5) What dynamical response will the ice rise have under future environmental change?", "east": -164.0, "geometry": "POINT(-169.5 -83.05)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS", "is_usap_dc": true, "keywords": "Amd/Us; FIELD SURVEYS; Antarctica; USA/NSF; AMD; USAP-DC; Radar; GLACIERS/ICE SHEETS", "locations": "Antarctica", "north": -82.7, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard; Koutnik, Michelle; Winberry, Paul", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "CReSIS/ku.edu; USAP-DC", "science_programs": null, "south": -83.4, "title": "Collaborative Research: Grounding Line Dynamics: Crary Ice Rise Revisited", "uid": "p0010026", "west": -175.0}, {"awards": "1543031 Ivany, Linda", "bounds_geometry": null, "dataset_titles": "NetCDF outputs from middle Eocene climate simulation using the GENESIS global circulation model ; Organic carbon isotope data from serially sampled Eocene driftwood from the La Meseta Fm., Seymour ; Oxygen isotope data from serially sampled Eocene bivalves from the La Meseta Fm., Seymour Island, Antarctica ", "datasets": [{"dataset_uid": "601175", "doi": "10.15784/601175 ", "keywords": "Antarctica; Atmosphere; Climate Model; Computer Model; Eocene; Genesis; Global Circulation Model; Modeling; Model Output; Seasonality; Temperature", "people": "Judd, Emily", "repository": "USAP-DC", "science_program": null, "title": "NetCDF outputs from middle Eocene climate simulation using the GENESIS global circulation model ", "url": "https://www.usap-dc.org/view/dataset/601175"}, {"dataset_uid": "601174", "doi": "10.15784/601174", "keywords": "Antarctica; Biota; Bivalves; Cucullaea; Eocene; Glaciers/ice Sheet; Glaciers/Ice Sheet; Isotope Data; La Meseta Formation; Mass Spectrometer; Mass Spectrometry; Oxygen Isotope; Paleotemperature; Retrotapes; Seasonality; Seymour Island", "people": "Judd, Emily", "repository": "USAP-DC", "science_program": null, "title": "Oxygen isotope data from serially sampled Eocene bivalves from the La Meseta Fm., Seymour Island, Antarctica ", "url": "https://www.usap-dc.org/view/dataset/601174"}, {"dataset_uid": "601173", "doi": "10.15784/601173 ", "keywords": "Antarctica; Carbon Isotopes; Driftwood; Eocene; Geochemistry; Geochronology; Isotope Data; La Meseta Formation; Mass Spectrometer; Mass Spectrometry; Organic Carbon Isotopes; Seasonality; Seymour Island; Wood", "people": "Judd, Emily", "repository": "USAP-DC", "science_program": null, "title": "Organic carbon isotope data from serially sampled Eocene driftwood from the La Meseta Fm., Seymour ", "url": "https://www.usap-dc.org/view/dataset/601173"}], "date_created": "Tue, 23 Apr 2019 00:00:00 GMT", "description": "In order to understand what environmental conditions might look like for future generations, we need to turn to archives of past times when the world was indeed warmer, before anyone was around to commit them to collective memory. The geologic record of Earth\u0027s past offers a glimpse of what could be in store for the future. Research by Ivany and her team looks to Antarctica during a time of past global warmth to see how seasonality of temperature and rainfall in coastal settings are likely to change in the future. They will use the chemistry of fossils (a natural archive of these variables) to test a provocative hypothesis about near-monsoonal conditions in the high latitudes when the oceans are warm. If true, we can expect high-latitude shipping lanes to become more hazardous and fragile marine ecosystems adapted to constant cold temperatures to suffer. With growing information about how human activities are likely to affect the planet in the future, we will be able to make more informed decisions about policies today. This research involves an international team of scholars, including several women scientists, training of graduate students, and a public museum exhibit to educate children about how we study Earth\u0027s ancient climate and what we can learn from it.\u003cbr/\u003e\u003cbr/\u003eAntarctica is key to an understanding how Earth?s climate system works under conditions of elevated CO2. The poles are the most sensitive regions on the planet to climate change, and the equator-to-pole temperature gradient and the degree to which high-latitude warming is amplified are important components for climate models to capture. Accurate proxy data with good age control are therefore critical for testing numerical models and establishing global patterns. The La Meseta Formation on Seymour Island is the only documented marine section from the globally warm Eocene Epoch exposed in outcrop on the continent; hence its climate record is integral to studies of warming. Early data suggest the potential for strongly seasonal precipitation and runoff in coastal settings. This collaboration among paleontologists, geochemists, and climate modelers will test this using seasonally resolved del-18O data from fossil shallow marine bivalves to track the evolution of seasonality through the section, in combination with independent proxies for the composition of summer precipitation (leaf wax del-D) and local seawater (clumped isotopes). The impact of the anticipated salinity stratification on regional climate will be evaluated in the context of numerical climate model simulations. In addition to providing greater clarity on high-latitude conditions during this time of high CO2, the combination of proxy and model results will provide insights about how Eocene warmth may have been maintained and how subsequent cooling came about. As well, a new approach to the analysis of shell carbonates for 87Sr/86Sr will allow refinements in age control so as to allow correlation of this important section with other regions to clarify global climate gradients. The project outlined here will develop new and detailed paleoclimate records from existing samples using well-tuned as well as newer proxies applied here in novel ways. Seasonal extremes are climate parameters generally inaccessible to most studies but critical to an understanding of climate change; these are possible to resolve in this well-preserved, accretionary-macrofossil-bearing section. This is an integrated study that links marine and terrestrial climate records for a key region of the planet across the most significant climate transition in the Cenozoic.", "east": -56.0, "geometry": "POINT(-56.5 -64.25)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "PALEOCLIMATE RECONSTRUCTIONS; USAP-DC; ISOTOPES; NOT APPLICABLE; MACROFOSSILS; Antarctica", "locations": "Antarctica", "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Ivany, Linda; Lu, Zunli; Junium, Christopher; Samson, Scott", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.5, "title": "Seasonality, Summer Cooling, and Calibrating the Approach of the Icehouse in Late Eocene Antarctica", "uid": "p0010025", "west": -57.0}, {"awards": "1247510 Detrich, H. William", "bounds_geometry": null, "dataset_titles": "E-MTAB-6759: RNA-seq across tissues in four Notothenioid species (Antarctic icefish); Expedition Data; Expedition data of LMG1003; Expedition data of LMG1004; PRJNA420419: Chaenocephalus aceratus Genome sequencing; PRJNA66471: Notothenia coriiceps Genome Sequencing Notothenia coriiceps isolate:Sejong01 (black rockcod); S-BSST 132: Assembled Transcriptomes for Berthelot et al. (2018); SRA091269: Notothenia coriiceps RNA Raw Sequence Reads; SRP047484: RAD-tag Sequences of Genetically Mapped Notothenia coriiceps Embryos ; SRP118539: RAD-tag Sequences of Genetically Mapped Chaenocephalus aceratus Embryos", "datasets": [{"dataset_uid": "200093", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "SRP118539: RAD-tag Sequences of Genetically Mapped Chaenocephalus aceratus Embryos", "url": "https://www.ncbi.nlm.nih.gov/sra/SRP118539 "}, {"dataset_uid": "200142", "doi": "", "keywords": null, "people": null, "repository": "NCBI BioProject", "science_program": null, "title": "PRJNA66471: Notothenia coriiceps Genome Sequencing Notothenia coriiceps isolate:Sejong01 (black rockcod)", "url": "https://www.ncbi.nlm.nih.gov/bioproject/66471"}, {"dataset_uid": "200145", "doi": "", "keywords": null, "people": null, "repository": "BioStudies", "science_program": null, "title": "S-BSST 132: Assembled Transcriptomes for Berthelot et al. (2018)", "url": "https://www.ebi.ac.uk/biostudies/studies/S-BSST132"}, {"dataset_uid": "200146", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "SRP047484: RAD-tag Sequences of Genetically Mapped Notothenia coriiceps Embryos ", "url": "https://www.ncbi.nlm.nih.gov/sra/?term=SRP047484"}, {"dataset_uid": "002684", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1003", "url": "https://www.rvdata.us/search/cruise/LMG1003"}, {"dataset_uid": "002685", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1004", "url": "https://www.rvdata.us/search/cruise/LMG1004"}, {"dataset_uid": "001508", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0807"}, {"dataset_uid": "200144", "doi": "", "keywords": null, "people": null, "repository": "Array Express", "science_program": null, "title": "E-MTAB-6759: RNA-seq across tissues in four Notothenioid species (Antarctic icefish)", "url": "https://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-6759/"}, {"dataset_uid": "001509", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0806"}, {"dataset_uid": "200143", "doi": "", "keywords": null, "people": null, "repository": "NCBI BioProject", "science_program": null, "title": "PRJNA420419: Chaenocephalus aceratus Genome sequencing", "url": "https://www.ncbi.nlm.nih.gov/bioproject/420419"}, {"dataset_uid": "200026", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "SRA091269: Notothenia coriiceps RNA Raw Sequence Reads", "url": "https://www.ncbi.nlm.nih.gov/sra/?term=SRA091269"}], "date_created": "Mon, 08 Apr 2019 00:00:00 GMT", "description": "Since the advent of Antarctic continental glaciation, the opening of the Drake Passage between South America and the Antarctic Peninsula, and the onset of cooling of the Southern Ocean ~40-25 million years ago, evolution of the Antarctic marine biota has been driven by the development of extreme cold temperatures. As circum-Antarctic coastal temperatures declined during this period from ~20\u00b0C to the modern -1.9 to +2.0\u00b0C (reached ~8-10 million years ago), the psychrophilic (cold-loving) ectotherms of the Southern Ocean evolved compensatory molecular, cellular, and physiological traits that enabled them to maintain normal metabolic function at cold temperatures. Today, these organisms are threatened by rapid warming of the Southern Ocean over periods measured in centuries (as much as 5\u00b0C/100 yr), a timeframe so short that re-adaptation and/or acclimatization to the \"new warm\" may not be possible. Thus, the long-term goals of this research project are: 1) to understand the biochemical and physiological capacities of the embryos of Antarctic notothenioid fish to resist or compensate for rapid oceanic warming; and 2) to assess the genetic toolkit available to support the acclimatization and adaptation of Antarctic notothenioid embryos to their warming habitat. The specific aims of this work are: 1) to determine the capacity of the chaperonin complex of notothenioid fishes to assist protein folding at temperatures between -4 and +20\u00b0C; and 2) to evaluate the genetic responses of notothenioid embryos, measured as global differential gene transcription, to temperature challenge, with -1.9\u00b0C as the \"normal\" control and +4 and +10\u00b0C as high temperature insults.\r\nThe physiology of embryonic development of marine stenotherms under future climate change scenarios is an important but understudied problem. This project will provide valuable insights into the capacity of Antarctic fish embryos to acclimatize and adapt to plausible climate change scenarios by examining multiple levels of biological organization, from the biochemical to the organismal. The results should also be broadly applicable to understanding the impact of global warming on marine biota worldwide. The research will also introduce graduate and undergraduate students to state-of-the-art biochemical, cellular, and molecular-biological research relevant to ecological and environmental issues of the Antarctic marine ecosystem.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e TRAWLS/NETS \u003e BOTTOM TRAWL", "is_usap_dc": false, "keywords": "AQUATIC SCIENCES; R/V LMG; USAP-DC; Southern Ocean", "locations": "Southern Ocean", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Detrich, H. William", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "NCBI SRA", "repositories": "Array Express; BioStudies; NCBI BioProject; NCBI SRA; R2R", "science_programs": null, "south": null, "title": "Protein Folding and Embryogenesis in Antarctic Fishes: A Comparative Approach to Environmental Stress", "uid": "p0010024", "west": null}, {"awards": "1743326 Kingslake, Jonathan", "bounds_geometry": null, "dataset_titles": "Report on Antarctic surface hydrology workshop, LDEO, 2018 ", "datasets": [{"dataset_uid": "601170", "doi": "10.15784/601170", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hydrology; Ice Sheet Stability; Ice Shelf; Report; Workshop", "people": "Bell, Robin; Kingslake, Jonathan; Trusel, Luke; Banwell, Alison; Das, Indrani; DeConto, Robert; Tedesco, Marco; Lenaerts, Jan; Schoof, Christian", "repository": "USAP-DC", "science_program": null, "title": "Report on Antarctic surface hydrology workshop, LDEO, 2018 ", "url": "https://www.usap-dc.org/view/dataset/601170"}], "date_created": "Tue, 26 Mar 2019 00:00:00 GMT", "description": "Ice shelves are the floating portions of glaciers that terminate in the ocean. They are common around the periphery of Antarctica. The accumulation of surface meltwater on or near the surface of ice shelves can play a role in ice-shelf collapse, which leads to accelerated loss of grounded ice and sea-level rise. Recent studies have showed that present-day meltwater generation and movement across the surface of Antarctica is more widespread than previously thought and is expected to increase. Consequently, there is a growing need to address the role of surface water in forecasts of ice-shelf behavior. While much progress has been made, understanding of the role of water in ice-shelf collapse is still in its infancy. This award supports a workshop that will bring together experts from multiple disciplines that, together, can advance understanding of Antarctic surface hydrology and its role in the future stability of ice shelves. This workshop will bring together U.S. and international scientists with expertise in ice-sheet dynamics, glacial hydrology, climatology, and other disciplines to identify critical knowledge gaps and move the community towards answering fundamental questions such as: What climate dynamics are responsible for surface meltwater generation in Antarctica? What controls the spatiotemporal distribution of meltwater ponds on Antarctic ice shelves? Where is meltwater generated, where does it pond today, and how will this change this century? How will meltwater impact ice shelves? How will surface hydrology impact sea-level this century? The deliberations will be captured in a workshop report.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; ICE SHEETS; North America; USAP-DC", "locations": "North America", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Kingslake, Jonathan; Tedesco, Marco; Trusel, Luke", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Workshop on Antarctic Surface Hydrology and Future Ice-shelf Stability", "uid": "p0010021", "west": null}, {"awards": "1758224 Salvatore, Mark", "bounds_geometry": "POLYGON((-180 -83,-178 -83,-176 -83,-174 -83,-172 -83,-170 -83,-168 -83,-166 -83,-164 -83,-162 -83,-160 -83,-160 -83.4,-160 -83.8,-160 -84.2,-160 -84.6,-160 -85,-160 -85.4,-160 -85.8,-160 -86.2,-160 -86.6,-160 -87,-162 -87,-164 -87,-166 -87,-168 -87,-170 -87,-172 -87,-174 -87,-176 -87,-178 -87,180 -87,178 -87,176 -87,174 -87,172 -87,170 -87,168 -87,166 -87,164 -87,162 -87,160 -87,160 -86.6,160 -86.2,160 -85.8,160 -85.4,160 -85,160 -84.6,160 -84.2,160 -83.8,160 -83.4,160 -83,162 -83,164 -83,166 -83,168 -83,170 -83,172 -83,174 -83,176 -83,178 -83,-180 -83))", "dataset_titles": "Laboratory Hyperspectral Reflectance Data of Central Transantarctic Mountain Rocks and Sediments; Orbital imagery used for SpecMap project", "datasets": [{"dataset_uid": "002735", "doi": null, "keywords": null, "people": null, "repository": "PGC", "science_program": null, "title": "Orbital imagery used for SpecMap project", "url": "https://www.pgc.umn.edu/projects/specmap/"}, {"dataset_uid": "601163", "doi": "10.15784/601163", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Remote Sensing; Rocks; Solid Earth; Spectroscopy; Transantarctic Mountains", "people": "Salvatore, Mark", "repository": "USAP-DC", "science_program": null, "title": "Laboratory Hyperspectral Reflectance Data of Central Transantarctic Mountain Rocks and Sediments", "url": "https://www.usap-dc.org/view/dataset/601163"}], "date_created": "Thu, 14 Mar 2019 00:00:00 GMT", "description": "Intellectual Merit:\u003cbr/\u003eIce free rock outcrops in the Transantarctic Mountains provide the only accessible windows into the interior of the ice covered Antarctic continent; they are extremely remote and difficult to study. This region also hosts the highest latitude ice-free valley systems on the planet. Based on two interdisciplinary workshops, the Transantarctic region near the Shackleton Glacier has been identified as a high priority site for further studies, with a field camp proposed for the 2015-2016 Antarctic field season. The geology of this region has been studied since the heroic era of Antarctic exploration, in the early 1900s, but geologic mapping has not been updated in more than forty years, and existing maps are at poor resolution (typically 1:250,000).\u003cbr/\u003e\u003cbr/\u003eThis project would utilize the WorldView-2 multispectral orbital dataset to supplement original geologic mapping efforts near the proposed 2015-2016 Shackleton Glacier camp. The WorldView-2 satellite is the only multispectral orbiting sensor capable of imaging the entirety of the Transantarctic Mountains, and all necessary data are currently available to the Polar Geospatial Center. High-latitude atmospheric correction of multispectral data for geologic investigations has only recently been tested, but has never been applied to WorldView-2 data, and never for observations of this type. Therefore, this research will require technique refinements and methodological developements to accomplish the goals. Atmospheric correction refinements and spectral validation will be made possible by laboratory spectroscopic measurements of rock samples currently stored at the U.S. Polar Rock Repository, at the Ohio State University. This project will result in spectral unit identification and boundary mapping at a factor of four higher resolution (1:62,500) than previous geologic mapping efforts, and more detailed investigations (1:5,123) are possible at resolutions more than a factor of forty-eight improved over previous geologic maps. Validated spectral mapping at these improved resolutions will allow for detailed lithologic, and potentially biologic, mapping using existing satellite imagery. This will greatly enhance planning capabilities, thus maximizing the efficiency of the scientific research and support logistics associated with the Shackleton Glacier deep field camp.\u003cbr/\u003e\u003cbr/\u003eBroader impacts:\u003cbr/\u003eThe proposed work will have multiple impacts on the broader scientific community. First, the refinement of existing atmospheric correction methodologies, and the development of new spectral mapping techniques, may substantially improve our ability to remotely investigate geologic surfaces throughout Antarctica. The ability to validate this orbital dataset will be of use to both current and future geologic, environmental, and biologic studies, potentially across the entire continent. The project will yield a specific spectral mapping product (at a scale of 1:62,500) to the scientific community by a targeted date of 01 March 2014, in order to support proposals submitted to the National Science Foundation for the proposed 2015/2016 Shackleton Glacier camp. High-resolution spectral mapping products (up to a maximum resolution of 2 meters per pixel) will also be generated for regions of particular scientific interest. The use of community based resources, such as Polar Geospatial Center (PGC) imagery and U.S. Polar Rock Repository rock samples, will generate new synergistic and collaborative research possibilities within the Antarctic research community. In addition, the lead PI (Salvatore) is an early career scientist who is active in both Antarctic and planetary remote sensing. There are overlaps in the calibration, correction, and validation of remote spectral datasets for Antarctic and planetary applications which can lead to benefits and insights to an early career PI, as well as the two communities.", "east": -160.0, "geometry": "POINT(180 -85)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; Antarctica; GEOCHEMISTRY; LANDSCAPE; REFLECTED INFRARED; USAP-DC", "locations": "Antarctica", "north": -83.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Salvatore, Mark", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "PGC", "repositories": "PGC; USAP-DC", "science_programs": null, "south": -87.0, "title": "EAGER: Surface Variability and Spectral Analyses of the Central Transantarctic Mountains, Antarctica", "uid": "p0010020", "west": 160.0}, {"awards": "9725024 Jacobs, Stanley", "bounds_geometry": "POLYGON((140 -65,141 -65,142 -65,143 -65,144 -65,145 -65,146 -65,147 -65,148 -65,149 -65,150 -65,150 -65.3,150 -65.6,150 -65.9,150 -66.2,150 -66.5,150 -66.8,150 -67.1,150 -67.4,150 -67.7,150 -68,149 -68,148 -68,147 -68,146 -68,145 -68,144 -68,143 -68,142 -68,141 -68,140 -68,140 -67.7,140 -67.4,140 -67.1,140 -66.8,140 -66.5,140 -66.2,140 -65.9,140 -65.6,140 -65.3,140 -65))", "dataset_titles": "Expedition Data; R/V Nathaniel B. Palmer NBP0008 - Expedition Data; \r\nSummer Oceanographic Measurements near the Mertz Polynya NBP0008", "datasets": [{"dataset_uid": "200023", "doi": "10.7284/905461", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "R/V Nathaniel B. Palmer NBP0008 - Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0008"}, {"dataset_uid": "001885", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0008"}, {"dataset_uid": "200022", "doi": "10.15784/601161 ", "keywords": null, "people": null, "repository": "USAP-DC", "science_program": null, "title": "\r\nSummer Oceanographic Measurements near the Mertz Polynya NBP0008", "url": "https://www.usap-dc.org/view/dataset/601161"}], "date_created": "Mon, 11 Mar 2019 00:00:00 GMT", "description": "This project will study the dynamics of Circumpolar Deep Water intruding on the continental shelf of the West Antarctic coast, and the effect of this intrusion on the production of cold, dense bottom water, and melting at the base of floating glaciers and ice tongues. It will concentrate on the Amundsen Sea shelf, specifically in the region of the Pine Island Glacier, the Thwaites Glacier, and the Getz Ice Shelf. Circumpolar Deep Water (CDW) is a relatively warm water mass (warmer than +1.0 deg Celsius) which is normally confined to the outer edge of the continental shelf by an oceanic front separating this water mass from colder and saltier shelf waters. In the Amundsen Sea however, the deeper parts of the continental shelf are filled with nearly undiluted CDW, which is mixed upward, delivering significant amounts of heat to the base of the floating glacier tongues and the ice shelf. The melt rate beneath the Pine Island Glacier averages ten meters of ice per year with local annual rates reaching twenty meters. By comparison, melt rates beneath the Ross Ice Shelf are typically twenty to forty centimeters of ice per year. In addition, both the Pine Island and the Thwaites Glacier are extremely fast-moving, and have a significant effect on the regional ice mass balance of West Antarctica. This project therefore has an important connection to antarctic glaciology, particularly in assessing the combined effect of global change on the antarctic environment. The particular objectives of the project are (1) to delineate the frontal structure on the continental shelf sufficiently to define quantitatively the major routes of CDW inflow, meltwater outflow, and the westward evolution of CDW influence; (2) to use the obtained data set to validate a three-dimensional model of sub-ice ocean circulation that is currently under construction, and (3) to refine the estiamtes of in situ melting on the mass balance of the antarctic ice sheet. The observational program will be carried out from the research vessel Nathaniel B. Palmer in February and March, 1999.", "east": 150.0, "geometry": "POINT(145 -66.5)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC; Southern Ocean; WATER MASSES; Antarctica", "locations": "Southern Ocean; Antarctica", "north": -65.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jacobs, Stanley; Visbeck, Martin", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -68.0, "title": "Circumpolar Deep Water and the West Antarctic Ice Sheet", "uid": "p0010019", "west": 140.0}, {"awards": "1750630 Smith, Craig", "bounds_geometry": "POLYGON((-64 -66,-63.3 -66,-62.6 -66,-61.9 -66,-61.2 -66,-60.5 -66,-59.8 -66,-59.1 -66,-58.4 -66,-57.7 -66,-57 -66,-57 -66.3,-57 -66.6,-57 -66.9,-57 -67.2,-57 -67.5,-57 -67.8,-57 -68.1,-57 -68.4,-57 -68.7,-57 -69,-57.7 -69,-58.4 -69,-59.1 -69,-59.8 -69,-60.5 -69,-61.2 -69,-61.9 -69,-62.6 -69,-63.3 -69,-64 -69,-64 -68.7,-64 -68.4,-64 -68.1,-64 -67.8,-64 -67.5,-64 -67.2,-64 -66.9,-64 -66.6,-64 -66.3,-64 -66))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 15 Feb 2019 00:00:00 GMT", "description": "Worldwide publicity surrounding the calving of an iceberg the size of Delaware in July 2017 from the Larsen C Ice Shelf on the eastern side of the Antarctic Peninsula presents a unique and time-sensitive opportunity for research and education on polar ecosystems in a changing climate. The goal of this project was to convene a workshop, drawing from the large fund of intellectual capital in the US and international Antarctic research communities. The two-day workshop was designed to bring scientists with expertise in Antarctic biological, ecological, and ecosystem sciences to Florida State University to share knowledge, identify important research knowledge gaps, and outline strategic plans for research. \r\n\r\nMajor outcomes from the project were as follows. The international workshop to share and review knowledge concerning the response of Antarctic ecosystems to ice-shelf collapse was held at the Florida State University Coastal and Marine Laboratory (FSUCML) on 18-19 November 2017. Thirty-eight U.S. and international scientists attended the workshop, providing expertise in biological, ecological, geological, biogeographical, and glaciological sciences. Twenty-six additional scientists were either not able to attend or were declined because of having reached maximum capacity of the venue or for not responding to our invitation before the registration deadline.\r\n\r\nThe latest results of ice-shelf research were presented, providing an overview of the current scientific knowledge and understanding of the biological, ecological,\r\ngeological and cryospheric processes associated with ice-shelf collapse and its\r\necosystem-level consequences. In addition, several presentations focused on future plans to investigate the impacts of the recent Larsen C collapse. The following presentations were given at the meeting:\r\n\r\n1) Cryospheric dynamics and ice-shelf collapse \u2013 past and future (M. Truffer,\r\nUniversity of Alaska, Fairbanks)\r\n2) The geological history and geological impacts of ice-shelf collapse on the Antarctic Peninsula (Scottt Ishman, Amy Leventer)\r\n3) Pelagic ecosystem responses to ice-shelf collapse (Mattias Cape, Amy Leventer)\r\n4) Benthic ecosystem response to ice-shelf collapse (Craig Smith, Pavica Sr\u0161en, Ann Vanreusel)\r\n5) Larsen C and biotic homogenization of the benthos (Richard Aronson, James\r\nMcClintock, Kathryn Smith, Brittany Steffel)\r\n6) British Antarctic Survey: plans for Larsen C investigations early 2018 and in the\r\nfuture (Huw Griffiths)\r\n7) Feedback on the workshop \u201cClimate change impacts on marine ecosystems:\r\nimplications for management of living resources and conservation\u201d held 19-22\r\nSeptember 2017, Cambridge, UK (Alex Rogers)\r\n8) Past research activities and plans for Larsen field work by the Alfred Wegener\r\nInstitute, Germany (Charlotte Havermans, Dieter Piepenburg.\r\n\r\nOne of the salient points emerging from the presentations and ensuing discussions was that, given our poor abilities to predict ecological outcomes of ice-shelf collapses, major cross-disciplinary efforts are needed on a variety of spatial and temporal scales to achieve a broader, predictive understanding of ecosystem\r\nconsequences of climatic warming and ice-shelf failure. As part of the workshop, the FSUCML Polar Academy Team\u2014Dr. Emily Dolan, Dr. Heidi Geisz, Barbara Shoplock, and Dr. Jeroen Ingels\u2014initiated AntICE: \"Antarctic Influences of Climate Change on Ecosystems\" (AntICE). They reached out to various groups of school children in the local area (and continue to do so). The AntICE Team have been interacting with these children at Wakulla High School and Wakulla Elementary in Crawfordville; children from the Cornerstone Learning Community, Maclay Middle School, Gilchrist Elementary, and the School of Arts and Sciences in Tallahassee; and the Tallahassee-area homeschooling community to educate them about Antarctic ecosystems and ongoing climate change. The underlying idea was to\r\nmake the children aware of climatic changes in the Antarctic and their effect on\r\necosystems so they, in turn, can spread this knowledge to their communities, family\r\nand friends \u2013 acting as \u2018Polar Ambassadors\u2019. We collaborated with the Polar-ICE\r\nproject, an NSF-funded educational project that established the Polar Literacy\r\nInitiative. This program developed the Polar Literacy Principles, which outline\r\nessential concepts to improve public understanding of Antarctic and Arctic\r\necosystems. In the Polar Academy work, we used the Polar Literacy principles, the\r\nPolar Academy Team\u2019s own Antarctic scientific efforts, and the experience of the FSU outreach and education program to engage with the children. We focused on the importance of Antarctic organisms and ecosystems, the uniqueness of its biota and the significance of its food webs, as well as how all these are changing and will\r\nchange further with climate change. Using general presentations, case studies,\r\nscientific methodology, individual experiences, interactive discussions and Q\u0026A\r\nsessions, the children were guided through the many issues Antarctic ecosystems\r\nare facing. Over 300 \u0027Polar ambassadors\u0027 attended the interactive lectures and\r\nafterwards took their creativity to high latitudes by creating welcome letters, displays, dioramas, sculptures, videos and online media to present at the scientific workshop. Over 50 projects were created by the children (Please see supporting files for images). We were also joined by a photographer, Ryan David Reines, to document the event. More information, media and links to online outreach products are available at https://marinelab.fsu.edu/labs/ingels/outreach/polar-academy/", "east": -57.0, "geometry": "POINT(-60.5 -67.5)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; USAP-DC; ECOLOGICAL DYNAMICS; NOT APPLICABLE; MARINE ECOSYSTEMS; Weddell Sea", "locations": "Weddell Sea", "north": -66.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Craig", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repositories": null, "science_programs": null, "south": -69.0, "title": "Collaborative Research: RAPID/Workshop- Antarctic Ecosystem Research following Ice Shelf Collapse and Iceberg Calving Events", "uid": "p0010012", "west": -64.0}, {"awards": "1246407 Jenouvrier, Stephanie", "bounds_geometry": "POINT(70.2433 -49.6875)", "dataset_titles": "Demographic outputs and their variances for three life history complexes for the Southern Fulmar across contrasted sea ice conditions.; Desprez, M., Jenouvrier, S., Barbraud, C., Delord, K. and Weimerskirch, H., 2018. Linking oceanographic conditions, migratory schedules and foraging behaviour during the non\u2010breeding season to reproductive performance in a long\u2010lived seabird. Functional ecology, 32(8), pp.2040-2053.; Jenouvrier, S., Desprez, M., Fay, R., Barbraud, C., Weimerskirch, H., Delord, K. and Caswell, H., 2018. Climate change and functional traits affect population dynamics of a long\u2010lived seabird. Journal of Animal Ecology, 87(4), pp.906-920.; Linking oceanographic conditions, migratory schedules and foraging behaviour during the non-breeding season to reproductive performance in a long-lived seabird", "datasets": [{"dataset_uid": "200008", "doi": "10.1111/1365-2435.13117", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Desprez, M., Jenouvrier, S., Barbraud, C., Delord, K. and Weimerskirch, H., 2018. Linking oceanographic conditions, migratory schedules and foraging behaviour during the non\u2010breeding season to reproductive performance in a long\u2010lived seabird. Functional ecology, 32(8), pp.2040-2053.", "url": "https://datadryad.org/resource/doi:10.5061/dryad.pb209db"}, {"dataset_uid": "601140", "doi": "10.15784/601140", "keywords": "Albatross; Animal Behavior Observation; Antarctica; Biota; Birds; Black-Browed Albatross (thalassarche Melanophris); Field Investigations; Foraging; Kerguelen Island; Ocean Island/plateau; Ocean Island/Plateau; Southern Ocean", "people": "Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Linking oceanographic conditions, migratory schedules and foraging behaviour during the non-breeding season to reproductive performance in a long-lived seabird", "url": "https://www.usap-dc.org/view/dataset/601140"}, {"dataset_uid": "601585", "doi": "10.15784/601585", "keywords": "Antarctica; Biota; Birds; East Antarctica; Southern Fulmar", "people": "Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Demographic outputs and their variances for three life history complexes for the Southern Fulmar across contrasted sea ice conditions.", "url": "https://www.usap-dc.org/view/dataset/601585"}, {"dataset_uid": "200007", "doi": "10.1111/1365-2656.12827.", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Jenouvrier, S., Desprez, M., Fay, R., Barbraud, C., Weimerskirch, H., Delord, K. and Caswell, H., 2018. Climate change and functional traits affect population dynamics of a long\u2010lived seabird. Journal of Animal Ecology, 87(4), pp.906-920.", "url": "https://doi.org/10.5061/dryad.h5vk5"}], "date_created": "Thu, 31 Jan 2019 00:00:00 GMT", "description": "Understanding the ecological consequences - present and future-of climate change is a central question in conservation biology. The goal of this project is to identify the effects of climate change on the Black-Browed Albatross, a seabird breeding in the Southern Ocean. The Black-Browed Albatross exhibits remarkable flight adaptations, using winds as an energy source to glide for long distances. This is the basis of their foraging strategy, by which they obtain food for themselves and their offspring. Climate change, however, is expected to modify wind patterns over the Southern Ocean. This project will analyze the effect of winds on life history traits (foraging behaviors, body conditions and demographic traits), and the effects of these traits on populations. New demographic models will provide the link between foraging behavior and the physical environment, and evaluate the persistence of this population in the face of climate change.\u003cbr/\u003e\u003cbr/\u003eUnderstanding and predicting population responses to climate change is important because the world?s climate will continue to change throughout the 21st century and beyond. To help guide conservation strategies and policy decisions in the face of climate change, reliable assessments of population extinction risks are urgently needed. The Black-Browed Albatross is considered endangered by the International Union for Conservation of Nature due to recent drastic reductions in its population size. This project will improve our understanding of the mechanisms by which climate affects the life history and populations of Black-Browed Albatross to improve prediction of extinction risks under future climate change.", "east": 70.2433, "geometry": "POINT(70.2433 -49.6875)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Southern Ocean; NOT APPLICABLE; USAP-DC; BIRDS", "locations": "Southern Ocean", "north": -49.6875, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Jenouvrier, Stephanie", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "Dryad", "repositories": "Dryad; USAP-DC", "science_programs": null, "south": -49.6875, "title": "Linking Foraging Behaviors to Demography to understand Albatrosses Population Responses to Climate Change", "uid": "p0010002", "west": 70.2433}, {"awards": "1341440 Jin, Meibing; 1341547 Stroeve, Julienne; 1341558 Ji, Rubao", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic MIZ, Pack Ice and Polynya Maps from Passive Microwave Satellite Data; Ice-ocean-ecosystem model output; Sea ice chlorophyll concentrations in Antarctic coastal polynyas and seasonal ice zones", "datasets": [{"dataset_uid": "601219", "doi": "10.15784/601219", "keywords": "Antarctica; Biota; Chlorophyll; Chlorophyll Concentration; Oceans; Polynya; Sea Ice Concentration; Seasonal Ice Zone; Southern Ocean", "people": "Ji, Rubao", "repository": "USAP-DC", "science_program": null, "title": "Sea ice chlorophyll concentrations in Antarctic coastal polynyas and seasonal ice zones", "url": "https://www.usap-dc.org/view/dataset/601219"}, {"dataset_uid": "601115", "doi": "10.15784/601115", "keywords": "Antarctica; Pack Ice; Polynya; Sea Ice; Southern Ocean", "people": "Stroeve, Julienne", "repository": "USAP-DC", "science_program": null, "title": "Antarctic MIZ, Pack Ice and Polynya Maps from Passive Microwave Satellite Data", "url": "https://www.usap-dc.org/view/dataset/601115"}, {"dataset_uid": "601136", "doi": "10.15784/601136", "keywords": "Antarctica; Biota; Model Data; Oceans; Southern Ocean", "people": "Jin, Meibing", "repository": "USAP-DC", "science_program": null, "title": "Ice-ocean-ecosystem model output", "url": "https://www.usap-dc.org/view/dataset/601136"}], "date_created": "Tue, 20 Nov 2018 00:00:00 GMT", "description": "The aim of study is to understand how climate-related changes in snow and ice affect predator populations in the Antarctic, using the Ad\u00e9lie penguin as a focal species due to its long history as a Southern Ocean \u0027sentinel\u0027 species and the number of long-term research programs monitoring its abundance, distribution, and breeding biology. Understanding the environmental factors that control predator population dynamics is critically important for projecting the state of populations under future climate change scenarios, and for designing better conservation strategies for the Antarctic ecosystem. For the first time, datasets from a network of observational sites for the Ad\u00e9lie penguin across the entire Antarctic will be combined and analyzed, with a focus on linkages among the ice environment, primary production, and the population responses of Ad\u00e9lie penguins. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. The results of this project can be used to illustrate intuitively to the general public the complex interactions between ice, ocean, pelagic food web and top predators. This project also offers an excellent platform to demonstrate the process of climate-change science - how scientists simulate climate change scenarios and interpret model results. This project supports the training of undergraduate and graduate students in the fields of polar oceanography, plankton and seabird ecology, coupled physical-biological modeling and mathematical ecology. The results will be broadly disseminated to the general oceanographic research community through scientific workshops, conferences and peer-reviewed journal articles, and to undergraduate and graduate education communities, K-12 schools and organizations, and the interested public through web-based servers using existing infrastructure at the investigators\u0027 institutions. The key question to be addressed in this project is how climate impacts the timing of periodic biological events (phenology) and how interannual variation in this periodic forcing influences the abundance of penguins in the Antarctic. The focus will be on the timing of ice algae and phytoplankton blooms because the high seasonality of sea ice and associated pulsed primary productivity are major drivers of the Antarctic food web. This study will also examine the responses of Ad\u00e9lie penguins to changes in sea ice dynamics and ice algae-phytoplankton phenology. Ad\u00e9lie penguins, like many other Antarctic seabirds, are long-lived, upper trophic-level predators that integrate the effects of sea ice on the food web at regional scales, and thus serve as a reliable biological indicator of environmental changes. The proposed approach is designed to accommodate the limits of measuring and modeling the intermediate trophic levels between phytoplankton and penguins (e.g., zooplankton and fish) at the pan-Antarctic scale, which are important but latent variables in the Southern Ocean food web. Through the use of remotely sensed and in situ data, along with state of the art statistical approaches (e.g. wavelet analysis) and numerical modeling, this highly interdisciplinary study will advance our understanding of polar ecosystems and improve the projection of future climate change scenarios.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; MARINE ECOSYSTEMS; NOT APPLICABLE; Antarctica", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Jin, Meibing; Stroeve, Julienne; Ji, Rubao", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Phytoplankton Phenology in the Antarctic: Drivers, Patterns, and Implications for the Adelie Penguin", "uid": "p0000001", "west": -180.0}, {"awards": "1141916 Aster, Richard", "bounds_geometry": null, "dataset_titles": "Dynamic Response of the Ross Ice Shelf to Ocean Waves and Structure and Dynamics of the Ross Sea", "datasets": [{"dataset_uid": "002573", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Dynamic Response of the Ross Ice Shelf to Ocean Waves and Structure and Dynamics of the Ross Sea", "url": "http://www.iris.washington.edu/mda/XH?timewindow=2014-2017"}], "date_created": "Mon, 22 Oct 2018 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003e\u003cbr/\u003eThe PIs propose to establish an ice shelf network of 18 broadband seismographs deployed for two years to obtain high-resolution, mantle-scale images of Earth structure underlying the Ross Sea Embayment. Prior marine geophysical work provides good crustal velocity models for the region seaward of the ice shelf but mantle structure is constrained by only low-resolution images due to the lack of prior seismic deployments. The proposed stations would be established between Ross Island and Marie Byrd Land. These stations would fill a major geological gap within this extensional continental province and would link data sets collected in the Transantarctic Mountain transition/Plateau region (TAMSEIS) and in West Antarctica (POLENET) to improve resolution of mantle features beneath Antarctica. The proposed deployment would allow the PIs to collect seismic data without the expense, logistical complexity, and iceberg hazards associated with ocean bottom seismograph deployments. Tomographic models developed from the proposed data will be used to choose between competing models for the dynamics of the Ross Sea. In particular, the PIs will investigate whether a broad region of hot mantle, including the Eastern Ross Sea, indicates distributed recent tectonic activity, which would call into question models proposing that Eastern Ross extension ceased during the Mesozoic. These data will also allow the PIs to investigate the deeper earth structure to evaluate the possible role of mantle plumes and/or small-scale convection in driving regional volcanism and tectonism across the region.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003e\u003cbr/\u003eData from this deployment will be of broad interdisciplinary use. This project will support three graduate and two undergraduate students. At least one student will be an underrepresented minority student. The PIs will interact with the media and include K-12 educators in their fieldwork.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Earth Sciences", "paleo_time": null, "persons": "Aster, Richard", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": null, "title": "Collaborative Research: Mantle Structure and Dynamics of the Ross Sea from a Passive Seismic Deployment on the Ross Ice Shelf", "uid": "p0000761", "west": null}, {"awards": "1245915 Ray, Laura", "bounds_geometry": null, "dataset_titles": "Ground Penetrating Radar Grid Survey of the McMurdo Shear Zone", "datasets": [{"dataset_uid": "601102", "doi": "10.15784/601102", "keywords": "Antarctica; Firn; Folds; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Snow/ice; Snow/Ice", "people": "Kaluzienski, Lynn; Arcone, Steven; Ray, Laura; Lever, Jim; Walker, Ben; Koons, Peter", "repository": "USAP-DC", "science_program": null, "title": "Ground Penetrating Radar Grid Survey of the McMurdo Shear Zone", "url": "https://www.usap-dc.org/view/dataset/601102"}], "date_created": "Thu, 27 Sep 2018 00:00:00 GMT", "description": "This award supports an integrated field observation, remote sensing and numerical modeling study of the McMurdo Shear Zone (SZ). The SZ is a 5-10 km wide strip of heavily crevassed ice that separates the McMurdo and Ross ice shelves, and is an important region of lateral support for the Ross Ice Shelf. Previous radar and remote sensing studies reveal an enigmatic picture of the SZ in which crevasses detected at depth have no apparent surface expression, and have orientations which are possibly inconsistent with the observed flow field. In the proposed work, we seek to test the hypothesis that the SZ is a zone of chaotic Lagrangian mixing with (intersecting) buried crevasses which leads to rheological instability, potentially allowing large scale velocity discontinuities. The work will involve detailed field-based observations of crevasse distributions and structure using ground-penetrating radar, and GPS and remote sensing observations of the flow and stress field in the SZ. Because of the hazardous nature of the SZ, the radar surveys will be conducted largely with the aid of a lightweight robotic vehicle. Observations will be used to develop a finite element model of ice shelf shear margin behavior. The intellectual merit of this project is an increased understanding of ice shelf shear margin dynamics. Shear margins play a key role in ice shelf stability, and ice shelves in turn modulate the flux of ice from the ice sheet across the grounding line to the ocean. Insights from this project will improve large-scale models being developed to predict ice sheet evolution and future rates of sea level rise, which are topics of enormous societal concern. The broader impacts of the project include an improved basis for US Antarctic Program logistics planning as well as numerous opportunities to engage K-12 students in scientific discovery. Intensified crevassing in the shear zone between the Ross and McMurdo ice shelves would preclude surface crossing by heavy traverse vehicles which would lead to increased costs of delivering fuel to South Pole and a concomitant loss of flight time provided by heavy-lift aircraft for science missions on the continent. Our multidisciplinary research combining glaciology, numerical modeling, and robotics engineering is an engaging way to show how robotics can assist scientists in collecting hazardous field measurements. Our outreach activities will leverage Dartmouth\u0027s current NSF GK-12 program, build on faculty-educator relationships established during University of Maine\u0027s recent GK-12 program, and incorporate project results into University of Maine\u0027s IDEAS initiative, which integrates computational modeling with the existing science curriculum at the middle school level. This award has field work in Antarctica.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Ray, Laura", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Flow and Fracture Dynamics in an Ice Shelf Lateral Margin: Observations and Modeling of the McMurdo Shear Zone", "uid": "p0000701", "west": null}, {"awards": "0839142 Tulaczyk, Slawek; 0839059 Powell, Ross; 0838947 Tulaczyk, Slawek; 0838764 Anandakrishnan, Sridhar; 0838763 Anandakrishnan, Sridhar; 0838855 Jacobel, Robert; 0839107 Powell, Ross", "bounds_geometry": null, "dataset_titles": "Basal melt rates of the Ross Ice Shelf near the Whillans Ice Stream grounding line; Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats in W Antarctica - Lake and Ice Stream Subglacial Access Research Drilling (LISSARD); Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats - Robotic Access to Grounding-zones for Exploration and Science (RAGES); IRIS ID#s 201035, 201162, 201205; IRIS offers free and open access to a comprehensive data store of raw geophysical time-series data collected from a large variety of sensors, courtesy of a vast array of US and International scientific networks, including seismometers (permanent and temporary), tilt and strain meters, infrasound, temperature, atmospheric pressure and gravimeters, to support basic research aimed at imaging the Earth\u0027s interior.; Paleogene marine and terrestrial development of the West Antarctic Rift System: Biomarker Data Set; Paleogene marine and terrestrial development of the West Antarctic Rift System: Palynomorph Data Set; Radar Studies of Subglacial Lake Whillans and the Whillans Ice Stream Grounding Zone; The IRIS DMC archives and distributes data to support the seismological research community.; UNAVCO ID#s WHL1, WHL2, LA02, LA09 (full data link not provided)", "datasets": [{"dataset_uid": "601122", "doi": "10.15784/601122", "keywords": "Antarctica; Flexure Zone; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Shelf; Ice-Shelf Basal Melting; Ice-Shelf Strain Rate", "people": "Begeman, Carolyn", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Basal melt rates of the Ross Ice Shelf near the Whillans Ice Stream grounding line", "url": "https://www.usap-dc.org/view/dataset/601122"}, {"dataset_uid": "001405", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IRIS offers free and open access to a comprehensive data store of raw geophysical time-series data collected from a large variety of sensors, courtesy of a vast array of US and International scientific networks, including seismometers (permanent and temporary), tilt and strain meters, infrasound, temperature, atmospheric pressure and gravimeters, to support basic research aimed at imaging the Earth\u0027s interior.", "url": "http://www.iris.edu/hq/data_and_software"}, {"dataset_uid": "609594", "doi": "10.7265/N54J0C2W", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; GPS; Radar; Whillans Ice Stream", "people": "Jacobel, Robert", "repository": "USAP-DC", "science_program": null, "title": "Radar Studies of Subglacial Lake Whillans and the Whillans Ice Stream Grounding Zone", "url": "https://www.usap-dc.org/view/dataset/609594"}, {"dataset_uid": "000150", "doi": "", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "UNAVCO ID#s WHL1, WHL2, LA02, LA09 (full data link not provided)", "url": "http://www.unavco.org/"}, {"dataset_uid": "600154", "doi": "10.15784/600154", "keywords": "Antarctica; Biota; Diatom; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Lake Whillans; Paleoclimate; Ross Sea; Southern Ocean; Subglacial Lake; WISSARD", "people": "Powell, Ross", "repository": "USAP-DC", "science_program": null, "title": "Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats in W Antarctica - Lake and Ice Stream Subglacial Access Research Drilling (LISSARD)", "url": "https://www.usap-dc.org/view/dataset/600154"}, {"dataset_uid": "601234", "doi": "10.15784/601234", "keywords": "ACL; Antarctica; Biomarker; BIT Index; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Stream; Whillans Ice Stream; WISSARD", "people": "Coenen, Jason; Askin, Rosemary; Casta\u00f1eda, Isla; Warny, Sophie; Baudoin, Patrick; Scherer, Reed Paul", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Paleogene marine and terrestrial development of the West Antarctic Rift System: Biomarker Data Set", "url": "https://www.usap-dc.org/view/dataset/601234"}, {"dataset_uid": "000148", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IRIS ID#s 201035, 201162, 201205", "url": "http://ds.iris.edu/"}, {"dataset_uid": "601245", "doi": "10.15784/601245", "keywords": "Antarctica; Pollen; West Antarctica; WISSARD", "people": "Scherer, Reed Paul; Casta\u00f1eda, Isla; Askin, Rosemary; Warny, Sophie; Baudoin, Patrick; Coenen, Jason", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Paleogene marine and terrestrial development of the West Antarctic Rift System: Palynomorph Data Set", "url": "https://www.usap-dc.org/view/dataset/601245"}, {"dataset_uid": "600155", "doi": "10.15784/600155", "keywords": "Antarctica; Glaciology; Oceans; Southern Ocean; WISSARD", "people": "Powell, Ross", "repository": "USAP-DC", "science_program": null, "title": "Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats - Robotic Access to Grounding-zones for Exploration and Science (RAGES)", "url": "https://www.usap-dc.org/view/dataset/600155"}, {"dataset_uid": "001406", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "The IRIS DMC archives and distributes data to support the seismological research community.", "url": "http://ds.iris.edu/ds/nodes/dmc/"}], "date_created": "Mon, 10 Sep 2018 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The LISSARD project (Lake and Ice Stream Subglacial Access Research Drilling) is one of three research components of the WISSARD integrative initiative (Whillans Ice Stream Subglacial Access Research Drilling) that is being funded by the Antarctic Integrated System Science Program of NSF\u0027s Office of Polar Programs, Antarctic Division. The overarching scientific objective of WISSARD is to assess the role of water beneath a West Antarctic ice stream in interlinked glaciological, geological, microbiological, geochemical, and oceanographic systems. The LISSARD component of WISSARD focuses on the role of active subglacial lakes in determining how fast the West Antarctic ice sheet loses mass to the global ocean and influences global sea level changes. The importance of Antarctic subglacial lakes has only been recently recognized, and the lakes have been identified as high priority targets for scientific investigations because of their unknown contributions to ice sheet stability under future global warming scenarios. LISSARD has several primary science goals: A) To provide an observational basis for improving treatments of subglacial hydrological and mechanical processes in models of ice sheet mass balance and stability; B) To reconstruct the past history of ice stream stability by analyzing archives of past basal water and ice flow variability contained in subglacial sediments, porewater, lake water, and basal accreted ice; C) To provide background understanding of subglacial lake environments to benefit RAGES and GBASE (the other two components of the WISSARD project); and D) To synthesize data and concepts developed as part of this project to determine whether subglacial lakes play an important role in (de)stabilizing Antarctic ice sheets. We propose an unprecedented synthesis of approaches to studying ice sheet processes, including: (1) satellite remote sensing, (2) surface geophysics, (3) borehole observations and measurements and, (4) basal and subglacial sampling. \u003cbr/\u003e\u003cbr/\u003eINTELLECTUAL MERIT: The latest report of the Intergovernmental Panel on Climate Change recognized that the greatest uncertainties in assessing future global sea-level change stem from a poor understanding of ice sheet dynamics and ice sheet vulnerability to oceanic and atmospheric warming. Disintegration of the WAIS (West Antarctic Ice Sheet) alone would contribute 3-5 m to global sea-level rise, making WAIS a focus of scientific concern due to its potential susceptibility to internal or ocean-driven instability. The overall WISSARD project will test the overarching hypothesis that active water drainage connects various subglacial environments and exerts major control on ice sheet flow, geochemistry, metabolic and phylogenetic diversity, and biogeochemical transformations. \u003cbr/\u003e\u003cbr/\u003eBROADER IMPACTS: Societal Relevance: Global warming, melting of ice sheets and consequential sea-level rise are of high societal relevance. Science Resource Development: After a 9-year hiatus WISSARD will provide the US-science community with a renewed capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and assets will be accessible for future use through the NSF-OPP drilling contractor. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments (2007). Education and Outreach (E/O): These activities are grouped into four categories: i) increasing student participation in polar research by fully integrating them in our research programs; ii) introducing new investigators to the polar sciences by incorporating promising young investigators in our programs, iii) promotion of K-12 teaching and learning programs by incorporating various teachers and NSTA programs, and iv) reaching a larger public audience through such venues as popular science magazines, museum based activities and videography and documentary films. In summary, WISSARD will promote scientific exploration of Antarctica by conveying to the public the excitement of accessing and studying what may be some of the last unexplored aquatic environments on Earth, and which represent a potential analogue for extraterrestrial life habitats on Europa and Mars.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS", "is_usap_dc": true, "keywords": "USAP-DC; Ice Penetrating Radar; Antarctic; Subglacial Lake; Subglacial Hydrology; Grounding Line; Sea Level Rise; Bed Reflectivity; Ice Sheet Stability; Stability; Radar; Sub-Ice-Shelf; Geophysics; Biogeochemical; LABORATORY; Sediment; Sea Floor Sediment; Ice Thickness; Model; Ice Stream Stability; Basal Ice; SATELLITES; Ice Sheet Thickness; Subglacial; Antarctica; NOT APPLICABLE; Antarctic Ice Sheet; Ice Sheet; FIELD SURVEYS; Surface Elevation; Geochemistry; FIELD INVESTIGATION; Not provided", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Tulaczyk, Slawek; Fisher, Andrew; Powell, Ross; Anandakrishnan, Sridhar; Jacobel, Robert; Scherer, Reed Paul", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SATELLITES", "repo": "USAP-DC", "repositories": "IRIS; UNAVCO; USAP-DC", "science_programs": "WISSARD", "south": null, "title": "Collaborative Research: Integrative Study of Marine Ice Sheet Stability \u0026 Subglacial Life Habitats in W Antarctica - Lake \u0026 Ice Stream Subglacial Access Research Drilling (LISSARD)", "uid": "p0000105", "west": null}, {"awards": "1141866 Conway, Howard; 1141889 Winberry, J. Paul", "bounds_geometry": null, "dataset_titles": "Beardmore Glacier High-Frequency Impulse Radar Data; Geophysical measurements Beardmore Glacier, Antarctica; Project code ZF for passive seismic and 17-030 for active source", "datasets": [{"dataset_uid": "601713", "doi": "10.15784/601713", "keywords": "Antarctica; Beardmore Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Ice Penetrating Radar; Snow/ice; Snow/Ice", "people": "Conway, Howard; Hoffman, Andrew; Christianson, Knut", "repository": "USAP-DC", "science_program": null, "title": "Beardmore Glacier High-Frequency Impulse Radar Data", "url": "https://www.usap-dc.org/view/dataset/601713"}, {"dataset_uid": "000210", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Project code ZF for passive seismic and 17-030 for active source", "url": "https://ds.iris.edu/mda/17-030"}, {"dataset_uid": "601121", "doi": "10.15784/601121", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Thickness; Radar", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Geophysical measurements Beardmore Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601121"}], "date_created": "Sun, 09 Sep 2018 00:00:00 GMT", "description": "Conway/1141866\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to conduct a suite of experiments to study spatial and temporal variations of basal conditions beneath Beardmore Glacier, an East Antarctic outlet glacier that discharges into the Ross Sea Embayment. The intellectual merit of the project is that it should help verify whether or not global warming will play a much larger role in the future mass balance of ice sheets than previously considered. Recent observations of rapid changes in discharge of fast-flowing outlet glaciers and ice streams suggest that dynamical responses to warming could affect that ice sheets of Greenland and Antarctica. Assessment of possible consequences of these responses is hampered by the lack of information about the basal boundary conditions. The leading hypothesis is that variations in basal conditions exert strong control on the discharge of outlet glaciers. Airborne and surface-based radar measurements of Beardmore Glacier will be made to map the ice thickness and geometry of the sub-glacial trough and active and passive seismic experiments, together with ground-based radar and GPS measurements will be made to map spatial and temporal variations of conditions at the ice-bed interface. The observational data will be used to constrain dynamic models of glacier flow. The models will be used to address the primary controls on the dynamics of Antarctic outlet glaciers, the conditions at the bed, their spatial and temporal variation, and how such variability might affect the sliding and flow of these glaciers. The work will also explore whether or not these outlet glaciers could draw down the interior of East Antarctica, and if so, how fast. The study will take three years including two field seasons to complete and results from the work will be disseminated through public and professional meetings and journal publications. All data and metadata will be made available through the NSIDC web portal. The broader impacts of the work are that it will help elucidate the fundamental physics of outlet glacier dynamics which is needed to improve predictions of the response of ice sheets to changing environmental conditions. The project will also provide support for early career investigators and will provide training and support for one graduate and two undergraduate students. All collaborators are currently involved in scientific outreach and graduate student education and they are committed to fostering diversity.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC; Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard; Winberry, Paul", "platforms": "Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "IRIS; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: East Antarctic Outlet Glacier Dynamics", "uid": "p0000437", "west": null}, {"awards": "1443341 Hawley, Robert; 1443471 Koutnik, Michelle", "bounds_geometry": "POLYGON((110 -89,117 -89,124 -89,131 -89,138 -89,145 -89,152 -89,159 -89,166 -89,173 -89,180 -89,180 -89.1,180 -89.2,180 -89.3,180 -89.4,180 -89.5,180 -89.6,180 -89.7,180 -89.8,180 -89.9,180 -90,173 -90,166 -90,159 -90,152 -90,145 -90,138 -90,131 -90,124 -90,117 -90,110 -90,110 -89.9,110 -89.8,110 -89.7,110 -89.6,110 -89.5,110 -89.4,110 -89.3,110 -89.2,110 -89.1,110 -89))", "dataset_titles": "7MHz radar in the vicinity of South Pole; Firn density and compaction rates 50km upstream of South Pole; Firn temperatures 50km upstream of South Pole; Shallow radar near South Pole; South Pole area GPS velocities; SPICEcore Advection", "datasets": [{"dataset_uid": "601099", "doi": "10.15784/601099", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Radar; Snow Accumulation; Snow/ice; Snow/Ice", "people": "Conway, Howard; Fudge, T. J.; Lilien, David; Koutnik, Michelle; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Shallow radar near South Pole", "url": "https://www.usap-dc.org/view/dataset/601099"}, {"dataset_uid": "601266", "doi": "10.15784/601266", "keywords": "Antarctica; Ice Core Data; South Pole; SPICEcore", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SPICEcore Advection", "url": "https://www.usap-dc.org/view/dataset/601266"}, {"dataset_uid": "601525", "doi": "10.15784/601525", "keywords": "Antarctica; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Snow/ice; Snow/Ice; South Pole; SPICEcore; Temperature", "people": "Conway, Howard; Lilien, David; Koutnik, Michelle; Fudge, T. J.; Stevens, Christopher Max; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Firn temperatures 50km upstream of South Pole", "url": "https://www.usap-dc.org/view/dataset/601525"}, {"dataset_uid": "601369", "doi": "10.15784/601369", "keywords": "Antarctica; Ice Sheet", "people": "Conway, Howard; Waddington, Edwin D.; Fudge, T. J.; Stevens, Max; Lilien, David; Koutnik, Michelle", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "7MHz radar in the vicinity of South Pole", "url": "https://www.usap-dc.org/view/dataset/601369"}, {"dataset_uid": "601100", "doi": "10.15784/601100", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ice Velocity", "people": "Fudge, T. J.; Lilien, David; Waddington, Edwin D.; Conway, Howard; Koutnik, Michelle", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole area GPS velocities", "url": "https://www.usap-dc.org/view/dataset/601100"}, {"dataset_uid": "601680", "doi": "10.15784/601680", "keywords": "Antarctica; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Snow/ice; Snow/Ice; South Pole; Temperature", "people": "Waddington, Edwin D.; Koutnik, Michelle; Fudge, T. J.; Conway, Howard; Lilien, David; Stevens, Christopher Max", "repository": "USAP-DC", "science_program": null, "title": "Firn density and compaction rates 50km upstream of South Pole", "url": "https://www.usap-dc.org/view/dataset/601680"}], "date_created": "Thu, 14 Jun 2018 00:00:00 GMT", "description": "Ice-core records are critical to understanding past climate variations. An Antarctic ice core currently being drilled at the South Pole will allow detailed investigation of atmospheric gases and fill an important gap in understanding the pattern of climate variability across Antarctica. Critical to the interpretation of any ice core are: 1) accurate chronologies for both the ice and the trapped gas and 2) demonstration that records from the ice core reliably reflect climate. The proposed research will improve the ice and gas chronologies by making measurements of snow compaction in the upstream catchment in order to constrain age models of the ice. These measurements will be a key data set needed for better understanding and predicting time-varying conditions in the upper part of the ice sheet. The research team will measure the modern spatial gradients in accumulation rate, surface temperature, and water stable isotopes from shallow ice cores in the upstream catchment in order to determine the climate history from the ice-core record. The new ice-flow measurements will make it possible to define the path of ice from upstream to the South Pole ice-core drill site to assess spatial gradients in snowfall and to infer histories of snowfall from internal layers within the ice sheet. The project will be led by an early-career scientist, provide broad training to graduate students, and engage in public outreach on polar science.\u003cbr/\u003e\u003cbr/\u003eIce-core records of stable isotopes, aerosol-born particles, and atmospheric gases are critical to understanding past climate variations. The proposed research will improve the ice and gas chronologies in the South Pole ice core by making in situ measurements of firn compaction in the upstream catchment to constrain models of the gas-age ice-age difference. The firn measurements will be a key data set needed to form a constitutive relationship for firn, and will drive better understanding and prediction of transient firn evolution. The research team will measure the modern gradients in accumulation rate, surface temperature, and water stable isotopes in the upstream catchment to separate spatial (advection) variations from temporal (climate) variations in the ice-core records. The ice-flow measurements will define the flowline upstream of the drill site, assess spatial gradients in accumulation, and infer histories of accumulation from radar-observed internal layers. Results will directly enhance interpretation of South Pole ice-core records, and also advance understanding of firn densification and drive next-generation firn models.", "east": 180.0, "geometry": "POINT(145 -89.5)", "instruments": null, "is_usap_dc": true, "keywords": "FIRN; Firn; USAP-DC; South Pole; Radar; FIELD SURVEYS; ICE CORE RECORDS", "locations": "South Pole", "north": -89.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Koutnik, Michelle; Conway, Howard; Waddington, Edwin D.; Fudge, T. J.; Hawley, Robert L.; Osterberg, Erich", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: Characterization of Upstream Ice and Firn Dynamics affecting the South Pole Ice Core", "uid": "p0000200", "west": 110.0}, {"awards": "1341585 Sorlien, Christopher", "bounds_geometry": "POLYGON((-180 -73.33,-179.1 -73.33,-178.2 -73.33,-177.3 -73.33,-176.4 -73.33,-175.5 -73.33,-174.6 -73.33,-173.7 -73.33,-172.8 -73.33,-171.9 -73.33,-171 -73.33,-171 -73.864,-171 -74.398,-171 -74.932,-171 -75.466,-171 -76,-171 -76.534,-171 -77.068,-171 -77.602,-171 -78.136,-171 -78.67,-171.9 -78.67,-172.8 -78.67,-173.7 -78.67,-174.6 -78.67,-175.5 -78.67,-176.4 -78.67,-177.3 -78.67,-178.2 -78.67,-179.1 -78.67,180 -78.67,178.5 -78.67,177 -78.67,175.5 -78.67,174 -78.67,172.5 -78.67,171 -78.67,169.5 -78.67,168 -78.67,166.5 -78.67,165 -78.67,165 -78.136,165 -77.602,165 -77.068,165 -76.534,165 -76,165 -75.466,165 -74.932,165 -74.398,165 -73.864,165 -73.33,166.5 -73.33,168 -73.33,169.5 -73.33,171 -73.33,172.5 -73.33,174 -73.33,175.5 -73.33,177 -73.33,178.5 -73.33,-180 -73.33))", "dataset_titles": "Ross Sea unconformities digital grids in depth and two-way time", "datasets": [{"dataset_uid": "601098", "doi": "10.15784/601098", "keywords": "Antarctica; Continental Margin; Geology/Geophysics - Other; Marine Geoscience; Miocene; Oligocene; Seismic Reflection", "people": "Wilson, Douglas S.; Sorlien, Christopher", "repository": "USAP-DC", "science_program": null, "title": "Ross Sea unconformities digital grids in depth and two-way time", "url": "https://www.usap-dc.org/view/dataset/601098"}], "date_created": "Fri, 25 May 2018 00:00:00 GMT", "description": "Intellectual Merit:\u003cbr/\u003eThis project will produce a new compilation of Ross Sea seismic stratigraphy, including new interpretations, that can be used to provide boundary conditions on the tectonic and glacial evolution of West Antarctica and the Ross Sea. The principal goals include compilation of, and interpretation of, all available existing seismic reflection data for the Western Ross Sea, coupled with geophysical modeling to produce paleo-bathymetric reconstructions for the entire 800 km-wide Ross Sea. Specific tasks will include: extending existing work on mapping travel time to reflectors, identifying relations in the seismic data that indicate subsidence through sea level, constructing velocity models for converting travel time to thickness, and using the velocity models to estimate density and porosity of sediments for backstripping analysis. Modeling/backstripping efforts will be used to constrain past bathymetry. Digital interpretations and stratigraphic grids will be provided as supplements to publications. In that way the results of this study can be used in thermal subsidence modeling and restoration of eroded rock to other parts of Ross Embayment and Marie Byrd Land by others. Digital products may be provided in advance of publication to modelers in a way that will not hurt publication chances.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe results of this work will be important for paleo-geographic reconstructions of Antarctica and will therefore be of use to a broad range of researchers, particularly those working in the Ross Sea region. The digital products can be used to test models for the past fluctuations of West Antarctic ice sheets, and in planning for future sediment drilling projects. Two undergraduates to be chosen from applicants will be involved in summer internships held at the University of Rhode Island. Outreach will also include a new website and one or more Wikipedia entries related to Ross Sea sub-sea floor characteristics. The project includes an international collaboration with Dr. Chiara Sauli and others at Instituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS) in Italy.", "east": -171.0, "geometry": "POINT(177 -76)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": -73.33, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Sorlien, Christopher; Luyendyk, Bruce P.", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.67, "title": "Subsidence, Tilting, Sedimentation, and Oligocene-middle Miocene paleo-depth of Ross Sea", "uid": "p0000271", "west": 165.0}, {"awards": "1440435 Ducklow, Hugh; 2023425 Schofield, Oscar", "bounds_geometry": "POLYGON((-80 -63,-78.3 -63,-76.6 -63,-74.9 -63,-73.2 -63,-71.5 -63,-69.8 -63,-68.1 -63,-66.4 -63,-64.7 -63,-63 -63,-63 -63.8,-63 -64.6,-63 -65.4,-63 -66.2,-63 -67,-63 -67.8,-63 -68.6,-63 -69.4,-63 -70.2,-63 -71,-64.7 -71,-66.4 -71,-68.1 -71,-69.8 -71,-71.5 -71,-73.2 -71,-74.9 -71,-76.6 -71,-78.3 -71,-80 -71,-80 -70.2,-80 -69.4,-80 -68.6,-80 -67.8,-80 -67,-80 -66.2,-80 -65.4,-80 -64.6,-80 -63.8,-80 -63))", "dataset_titles": "Environmental Data Initiative Repository, Supporting LTER; Expedition Data; Expedition data of LMG1501; Expedition data of LMG1601; Expedition data of LMG1701; Expedition data of LMG1801; Expedition data of LMG1901; Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae); UAV images and video of whales in the Antarctic Penisula during LMG1802", "datasets": [{"dataset_uid": "200123", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1601", "url": "https://www.rvdata.us/search/cruise/LMG1601"}, {"dataset_uid": "200122", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1501", "url": "https://www.rvdata.us/search/cruise/LMG1501"}, {"dataset_uid": "002729", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1701", "url": "https://www.rvdata.us/search/cruise/LMG1701"}, {"dataset_uid": "601811", "doi": null, "keywords": "Antarctica; Bellingshausen Sea; Cryosphere; Southern Ocean", "people": "Desvignes, Thomas; McDowell, Jan; Cheng, Chi-Hing; Biesack, Ellen; Steinberg, Deborah; Hilton, Eric; Corso, Andrew", "repository": "USAP-DC", "science_program": "LTER", "title": "Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae)", "url": "https://www.usap-dc.org/view/dataset/601811"}, {"dataset_uid": "601318", "doi": "10.15784/601318", "keywords": "Aerial Imagery; Antarctica; Antarctic Peninsula; Biota; Camera; Humpback Whales; LMG1802; LTER; Minke Whales; Oceans; Palmer Station; Photo; Photo/video; Photo/Video; R/v Laurence M. Gould; Species Size; UAV; Video Data; Whales", "people": "Friedlaender, Ari; Bierlich, KC; Boyer, Keyvi; Dale, Julian; Nowacek, Douglas", "repository": "USAP-DC", "science_program": "LTER", "title": "UAV images and video of whales in the Antarctic Penisula during LMG1802", "url": "https://www.usap-dc.org/view/dataset/601318"}, {"dataset_uid": "000246", "doi": "", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "Environmental Data Initiative Repository, Supporting LTER", "url": "https://portal.edirepository.org/nis/browseServlet?searchValue=PAL"}, {"dataset_uid": "001367", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1701"}, {"dataset_uid": "200125", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1901", "url": "https://www.rvdata.us/search/cruise/LMG1901"}, {"dataset_uid": "200124", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1801", "url": "https://www.rvdata.us/search/cruise/LMG1801"}], "date_created": "Fri, 11 May 2018 00:00:00 GMT", "description": "The Palmer Antarctica LTER (Long Term Ecological Research) site has been in operation since 1990. The goal of all the LTER sites is to conduct policy-relevant research on ecological questions that require tens of years of data, and cover large geographical areas. For the Palmer Antarctica LTER, the questions are centered around how the marine ecosystem west of the Antarctica peninsula is responding to a climate that is changing as rapidly as any place on the Earth. For example, satellite observations over the past 35 years indicate the average duration of sea ice cover is now ~90 days (3 months!) shorter than it was. The extended period of open water has implications for many aspects of ecosystem research, with the concurrent decrease of Ad\u00c3\u00a8lie penguins within this region regularly cited as an exemplar of climate change impacts in Antarctica. Cutting edge technologies such as autonomous underwater (and possibly airborne) vehicles, seafloor moorings, and numerical modeling, coupled with annual oceanographic cruises, and weekly environmental sampling, enables the Palmer Antarctica LTER to expand and bridge the time and space scales needed to assess climatic impacts. This award includes for the first time study of the roles of whales as major predators in the seasonal sea ice zone ecosystem. The team will also focus on submarine canyons, special regions of enhanced biological activity, along the Western Antarctic Peninsula (WAP).\u003cbr/\u003e\u003cbr/\u003eThe current award\u0027s overarching research question is: How do seasonality, interannual variability, and long term trends in sea ice extent and duration influence the structure and dynamics of marine ecosystems and biogeochemical cycling? Specific foci within the broad question include: 1. Long-term change and ecosystem transitions. What is the sensitivity or resilience of the ecosystem to external perturbations as a function of the ecosystem state? 2. Lateral connectivity and vertical stratification. What are the effects of lateral transports of freshwater, heat and nutrients on local ocean stratification and productivity and how do they drive changes in the ecosystem? 3. Top-down controls and shifting baselines. How is the ecosystem responding to the cessation of whaling and subsequent long-term recovery of whale stocks? 4. Foodweb structure and biogeochemical processes. How do temporal and spatial variations in foodweb structure influence carbon and nutrient cycling, export, and storage? The broader impacts of the award leverage local educational partnerships including the Sandwich, MA STEM Academy, the New England Aquarium, and the NSF funded Polar Learning and Responding (PoLAR) Climate Change Education Partnership at Columbia\u0027s Earth Institute to build new synergies between Arctic and Antarctic, marine and terrestrial scientists and students, governments and NGOs. The Palmer Antarctic LTER will also conduct appropriate cross LTER site comparisons, and serve as a leader in information management to enable knowledge-building within and beyond the Antarctic, oceanographic, and LTER communities.", "east": -63.0, "geometry": "POINT(-71.5 -67)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "PELAGIC; USAP-DC; R/V LMG; NOT APPLICABLE; Palmer Station; LMG1701", "locations": "Palmer Station", "north": -63.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Ducklow, Hugh; Martinson, Doug; Schofield, Oscar", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "EDI; R2R; USAP-DC", "science_programs": "LTER", "south": -71.0, "title": "LTER Palmer, Antarctica (PAL): Land-Shelf-Ocean Connectivity, Ecosystem Resilience and Transformation in a Sea-Ice Influenced Pelagic Ecosystem", "uid": "p0000133", "west": -80.0}, {"awards": "1443232 Waddington, Edwin", "bounds_geometry": "POLYGON((110 -89,117 -89,124 -89,131 -89,138 -89,145 -89,152 -89,159 -89,166 -89,173 -89,180 -89,180 -89.1,180 -89.2,180 -89.3,180 -89.4,180 -89.5,180 -89.6,180 -89.7,180 -89.8,180 -89.9,180 -90,173 -90,166 -90,159 -90,152 -90,145 -90,138 -90,131 -90,124 -90,117 -90,110 -90,110 -89.9,110 -89.8,110 -89.7,110 -89.6,110 -89.5,110 -89.4,110 -89.3,110 -89.2,110 -89.1,110 -89))", "dataset_titles": "AC-ECM for SPICEcore; ECM (DC and AC) multi-track data and images from 2016 processing season", "datasets": [{"dataset_uid": "601366", "doi": "10.15784/601366", "keywords": "Antarctica", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "ECM (DC and AC) multi-track data and images from 2016 processing season", "url": "https://www.usap-dc.org/view/dataset/601366"}, {"dataset_uid": "601189", "doi": " 10.15784/601189 ", "keywords": "Antarctica; Electrical Conductivity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Physical Properties; Snow/ice; Snow/Ice; South Pole; SPICEcore; Volcanic", "people": "Waddington, Edwin D.; Fudge, T. J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "AC-ECM for SPICEcore", "url": "https://www.usap-dc.org/view/dataset/601189"}], "date_created": "Tue, 08 May 2018 00:00:00 GMT", "description": "Ice cores record detailed histories of past climate variations. The South Pole ice core will allow investigation of atmospheric trace gases and fill an important gap in understanding the pattern of climate variability across Antarctica. An accurate timescale that assigns an age to the ice at each depth in the core is essential to interpretation of the ice-core records. This work will use electrical methods to identify volcanic eruptions throughout the past ~40,000 years in the core by detecting the enhanced electrical conductance in those layers due to volcanic impurities in the ice. These eruptions will be pattern-matched to other cores across Antarctica, synchronizing the timing of climate variations among cores and allowing the precise timescales developed for other Antarctic ice cores to be transferred to the South Pole ice core. The well-dated records of volcanic forcing will be combined with records of atmospheric gases, stable water-isotopes, and aerosols to better understand the large natural climate variations of the past 40,000 years. \u003cbr/\u003e \u003cbr/\u003eThe electrical conductance method and dielectric profiling measurements will be made along the length of each section of the South Pole ice core at the National Ice Core Lab. These measurements will help to establish a timescale for the core. Electrical measurements will provide a continuous record of volcanic events for the entire core including through the brittle ice (550-1250m representing ~10,000-20,000 year-old ice) where the core quality and thin annual layers may prevent continuous melt analysis and cause discrete measurements to miss volcanic events. The electrical measurements also produce a 2-D image of the electrical layering on a longitudinal cut surface of each core. These data will be used to identify any irregular or absent layering that would indicate a stratigraphic disturbance in the core. A robust chronology is essential to interpretation of the paleoclimate records from the South Pole ice core. The investigators will engage teachers through talks and webinars with the National Science Teachers Association and will share information with the public at events such as Polar Science Weekend at the Pacific Science Center. Results will be disseminated through publications and conference presentations and the data will be archived and publicly available.", "east": 180.0, "geometry": "POINT(145 -89.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; USA/NSF; Amd/Us; AMD; LABORATORY", "locations": null, "north": -89.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fudge, T. J.; Waddington, Edwin D.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Using Electrical Conductance Measurements to Develop the South Pole Ice Core Chronology", "uid": "p0000378", "west": 110.0}, {"awards": "1341729 Kirschvink, Joseph", "bounds_geometry": "POLYGON((-58.9 -63.5,-58.63 -63.5,-58.36 -63.5,-58.09 -63.5,-57.82 -63.5,-57.55 -63.5,-57.28 -63.5,-57.01 -63.5,-56.74 -63.5,-56.47 -63.5,-56.2 -63.5,-56.2 -63.62,-56.2 -63.74,-56.2 -63.86,-56.2 -63.98,-56.2 -64.1,-56.2 -64.22,-56.2 -64.34,-56.2 -64.46,-56.2 -64.58,-56.2 -64.7,-56.47 -64.7,-56.74 -64.7,-57.01 -64.7,-57.28 -64.7,-57.55 -64.7,-57.82 -64.7,-58.09 -64.7,-58.36 -64.7,-58.63 -64.7,-58.9 -64.7,-58.9 -64.58,-58.9 -64.46,-58.9 -64.34,-58.9 -64.22,-58.9 -64.1,-58.9 -63.98,-58.9 -63.86,-58.9 -63.74,-58.9 -63.62,-58.9 -63.5))", "dataset_titles": "2016 Paleomagnetic samples from the James Ross Basin, Antarctica; Expedition data of NBP1601", "datasets": [{"dataset_uid": "002665", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1601", "url": "https://www.rvdata.us/search/cruise/NBP1601"}, {"dataset_uid": "601094", "doi": "10.15784/601094", "keywords": "Antarctica; Geochronology; Geology/Geophysics - Other; Glaciology; James Ross Basin; Marine Geoscience; Marine Sediments", "people": "Kirschvink, Joseph; Skinner, Steven", "repository": "USAP-DC", "science_program": null, "title": "2016 Paleomagnetic samples from the James Ross Basin, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601094"}], "date_created": "Fri, 27 Apr 2018 00:00:00 GMT", "description": "Non-Technical Summary:\u003cbr/\u003e About 80 million years ago, the tip of the Antarctic Peninsula in the vicinity of what is now James Ross Island experienced an episode of rapid subsidence, creating a broad depositional basin that collected sediments eroding from the high mountains to the West. This depression accumulated a thick sequence of fossil-rich, organic-rich sediments of the sort that are known to preserve hydrocarbons, and for which Argentina, Chile, and the United Kingdom have overlapping territorial claims. The rocks preserve one of the highest resolution records of the biological and climatic events that led to the eventual death of the dinosaurs at the Cretaceous-Tertiary boundary (about 66 million years ago). A previous collaboration between scientists from the Instituto Ant\u00c3\u00a1rtico Argentino (IAA) and NSF-supported teams from Caltech and the University of Washington were able to show that this mass extinction event started nearly 50,000 years before the sudden impact of an asteroid. The asteroid obviously hit the biosphere hard, but something else knocked it off balance well before the asteroid hit. \u003cbr/\u003e A critical component of the previous work was the use of reversals in the polarity of the Earth?s magnetic field as a dating tool ? magnetostratigraphy. This allowed the teams to correlate the pattern of magnetic reversals from Antarctica with elsewhere on the planet. This includes data from a major volcanic eruption (a flood basalt province) that covered much of India 65 million years ago. The magnetic patterns indicate that the Antarctic extinction started with the first pulse of this massive eruption, which was also coincident with a rapid spike in polar temperature. The Argentinian and US collaborative teams will extend this magnetic polarity record back another ~ 20 million years in time, and expand it laterally to provide magnetic reversal time lines across the depositional basin. They hope to recover the end of the Cretaceous Long Normal interval, which is one of the most distinctive events in the history of Earth?s magnetic field. The new data should refine depositional models of the basin, allow better estimates of potential hydrocarbon reserves, and allow biotic events in the Southern hemisphere to be compared more precisely with those elsewhere on Earth. Other potential benefits of this work include exposing several US students and postdoctoral fellows to field based research in Antarctica, expanding the international aspects of this collaborative work via joint IAA/US field deployments, and follow-up laboratory investigations and personnel exchange of the Junior scientists.\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eTechnical Description of Project \u003cbr/\u003eThe proposed research will extend the stratigraphic record in the late Cretaceous and early Tertiary sediments (~ 83 to 65 Ma before present) of the James Ross Basin, Antarctica, using paleo-magnetic methods. Recent efforts provided new methods to analyze these rocks, yielding their primary magnetization, and producing both magnetic polarity patterns and paleomagnetic pole positions. This provided the first reliable age constraints for the younger sediments on Seymour Island, and quantified the sedimentation rate in this part of the basin. The new data will allow resolution of the stable, remnant magnetization of the sediments from the high deposition rate James Ross basin (Tobin et al., 2012), yielding precise chronology/stratigraphy. This approach will be extended to the re-maining portions of this sedimentary basin, and will allow quantitative estimates for tectonic and sedimentary processes between Cretaceous and Early Tertiary time. The proposed field work will refine the position of several geomagnetic reversals that occurred be-tween the end of the Cretaceous long normal period (Chron 34N, ~ 83 Ma), and the lower portion of Chron 31R (~ 71 Ma). Brandy Bay provides the best locality for calibrating the stratigraphic position of the top of the Cretaceous Long Normal Chron, C34N. Although the top of the Cretaceous long normal Chron is one of the most important correlation horizons in the entire geological timescale, it is not properly correlated to the southern hemisphere biostratigraphy. Locating this event, as well as the other reversals, will be a major addition to understanding of the geological history of the Antarctic Peninsula. These data will also help refine tectonic models for the evolution of the Southern continents, which will be of use across the board for workers in Cretaceous stratigraphy (including those involved in oil exploration).\u003cbr/\u003eThis research is a collaborative effort with Dr. Edward Olivero of the Centro Austral de Investigaciones Cientificas (CADIC/CONICET) and Prof. Augusto Rapalini of the University of Buenos Aires. The collaboration will include collection of samples on their future field excursions to important targets on and around James Ross Island, supported by the Argentinian Antarctic Program (IAA). Argentinian scientists and students will also be involved in the US Antarctic program deployments, proposed here for the R/V Laurence Gould, and will continue the pattern of joint international publication of the results.", "east": -56.2, "geometry": "POINT(-57.55 -64.1)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; R/V NBP; USAP-DC", "locations": null, "north": -63.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kirschvink, Joseph; Christensen, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -64.7, "title": "Paleomagnetism and Magnetostratigraphy of the James Ross Basin, Antarctica", "uid": "p0000276", "west": -58.9}, {"awards": "1142084 Nevitt, Gabrielle", "bounds_geometry": "POLYGON((40 -25,46 -25,52 -25,58 -25,64 -25,70 -25,76 -25,82 -25,88 -25,94 -25,100 -25,100 -28.5,100 -32,100 -35.5,100 -39,100 -42.5,100 -46,100 -49.5,100 -53,100 -56.5,100 -60,94 -60,88 -60,82 -60,76 -60,70 -60,64 -60,58 -60,52 -60,46 -60,40 -60,40 -56.5,40 -53,40 -49.5,40 -46,40 -42.5,40 -39,40 -35.5,40 -32,40 -28.5,40 -25))", "dataset_titles": "Satellite tracks of Black-browed Albatross in the Southern Indian Ocean", "datasets": [{"dataset_uid": "601093", "doi": "10.15784/601093", "keywords": "Albatross; Antarctica; Biota; Birds; Foraging; GPS Data; Southern Ocean; Stomach Temperature", "people": "Losekoot, Marcel; Nevitt, Gabrielle", "repository": "USAP-DC", "science_program": null, "title": "Satellite tracks of Black-browed Albatross in the Southern Indian Ocean", "url": "https://www.usap-dc.org/view/dataset/601093"}], "date_created": "Thu, 12 Apr 2018 00:00:00 GMT", "description": "With 70% of the Earth\u0027s surface being covered by oceans, a longstanding question of interest to the ecology of migratory seabirds is how they locate their prey across such vast distances. The project seeks to investigate the sensory strategies used in the foraging behavior of procellariiform seabirds, such as petrels, albatrosses and shearwaters. These birds routinely travel over thousands of kilometers of open ocean, apparently using their pronounced olfactory abilities (known to be up to a million times more sensitive than other birds) to identify productive marine areas or locate prey. High resolution tracking, such as provided by miniaturized GPS data loggers (+/- 5m; 10 second sampling), are needed to gain insight into some of the questions as to the sensory mechanisms birds use to locate their prey. Combining these tracking and positioning devices along with stomach temperature recorders capable of indicating prey ingestion, will provide a wealth of new behavioral information. Species specific foraging based on prey specific odors (e.g. krill vs fisheries vs. squid), and mixed strategies using olfaction and visual cues appear to be different for these different marine predators. \u003cbr/\u003e\u003cbr/\u003eAlbatrosses are increasingly an endangered species globally, and additional information as to their foraging strategies might lead to better conservation measures such as the avoidance of by-catch by long-line fisheries.\u003cbr/\u003eIntimate details of each species foraging activity patterns during the day and night and insight into the conservation of these top predators in pelagic Southern Ocean ecosystems are a few of the research directions these novel fine scale resolution approaches are yielding.", "east": 100.0, "geometry": "POINT(70 -42.5)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": -25.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Nevitt, Gabrielle", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -60.0, "title": "Applying High-resolution GPS Tracking to Characterize Sensory Foraging Strategies of the Black-browed Albatross, a Top Predator of the Southern Ocean Ecosystem", "uid": "p0000420", "west": 40.0}, {"awards": "1246292 Cary, Stephen", "bounds_geometry": "POLYGON((161.36062 -77.20215,161.610171 -77.20215,161.859722 -77.20215,162.109273 -77.20215,162.358824 -77.20215,162.608375 -77.20215,162.857926 -77.20215,163.107477 -77.20215,163.357028 -77.20215,163.606579 -77.20215,163.85613 -77.20215,163.85613 -77.291278,163.85613 -77.380406,163.85613 -77.469534,163.85613 -77.558662,163.85613 -77.64779,163.85613 -77.736918,163.85613 -77.826046,163.85613 -77.915174,163.85613 -78.004302,163.85613 -78.09343,163.606579 -78.09343,163.357028 -78.09343,163.107477 -78.09343,162.857926 -78.09343,162.608375 -78.09343,162.358824 -78.09343,162.109273 -78.09343,161.859722 -78.09343,161.610171 -78.09343,161.36062 -78.09343,161.36062 -78.004302,161.36062 -77.915174,161.36062 -77.826046,161.36062 -77.736918,161.36062 -77.64779,161.36062 -77.558662,161.36062 -77.469534,161.36062 -77.380406,161.36062 -77.291278,161.36062 -77.20215))", "dataset_titles": "Carbon-fixation rates and associated microbial communities; Carbon-fixation rates and associated microbial communities residing in arid and ephemerally wet Antarctic Dry Valley soils; Importance of Heterotrophic and Phototrophic N2 Fixation in the McMurdo Dry Valleys ; Microbial community composition of transiently wetted Antarctic Dry Valley soils.; Microbial population dynamics along a terrestrial Antarctic moisture gradient; Microbial population dynamics along a terrestrial wetted gradient", "datasets": [{"dataset_uid": "002738", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Carbon-fixation rates and associated microbial communities", "url": "https://www.ncbi.nlm.nih.gov/protein/?term=craig%20cary"}, {"dataset_uid": "002737", "doi": "", "keywords": null, "people": null, "repository": "KNB", "science_program": null, "title": "Carbon-fixation rates and associated microbial communities residing in arid and ephemerally wet Antarctic Dry Valley soils", "url": "https://knb.ecoinformatics.org/view/knb.756.1"}, {"dataset_uid": "002736", "doi": "", "keywords": null, "people": null, "repository": "EMBL", "science_program": null, "title": "Microbial population dynamics along a terrestrial Antarctic moisture gradient", "url": "https://www.ebi.ac.uk/ena/data/view/PRJEB27415"}, {"dataset_uid": "200013", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Importance of Heterotrophic and Phototrophic N2 Fixation in the McMurdo Dry Valleys ", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA505820"}, {"dataset_uid": "200014", "doi": "", "keywords": null, "people": null, "repository": "EMBL", "science_program": null, "title": "Microbial population dynamics along a terrestrial wetted gradient", "url": "https://www.ebi.ac.uk/ena/data/view/PRJEB7939"}, {"dataset_uid": "200015", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Microbial community composition of transiently wetted Antarctic Dry Valley soils.", "url": "https://www.ncbi.nlm.nih.gov/popset/?term=KP836071%20to%20KP836108"}], "date_created": "Wed, 14 Mar 2018 00:00:00 GMT", "description": "The McMurdo Dry Valleys in Antarctica are recognized as being the driest, coldest and probably one of the harshest environments on Earth. In addition to the lack of water, the biota in the valleys face a very limited supply of nutrients such as nitrogen compounds - necessary for protein synthesis. The glacial streams of the Dry Valleys have extensive cyanobacterial (blue green algae) mats that are a major source of carbon and nitrogen compounds to biota in this region. While cyanobacteria in streams are important as a source of these compounds, other non-photosynthetic bacteria also contribute a significant fraction (~50%) of fixed nitrogen compounds to valley biota. This research effort will involve an examination of exactly which non-phototrophic bacteria are involved in nitrogen fixation and what environmental factors are responsible for controlling nitrogen fixation by these microbes. This work will resolve the environmental factors that control the activity, abundance and diversity of nitrogen-fixing microbes across four of the McMurdo Dry Valleys. This will allow for comparisons among sites of differing latitude, temperature, elevation and exposure to water. These results will be integrated into a landscape wetness model that will help determine the impact of both cyanobacterial and non-photosynthetic nitrogen fixing microorganisms in this very harsh environment.\u003cbr/\u003e\u003cbr/\u003eThe Dry Valleys in many ways resemble the Martian environment, and understanding the primitive life and very simple nutrient cycling in the Dry Valleys has relevance for understanding how life might have once existed on other planets. Furthermore, the study of microbes from extreme environments has resulted in numerous biotechnological applications such as the polymerase chain reaction for amplifying DNA and mechanisms for freeze resistance in agricultural crops. Thus, this research should yield insights into how biota survive in extreme environments, and these insights could lead to other commercial applications.", "east": 163.85613, "geometry": "POINT(162.608375 -77.64779)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; Antarctica; USAP-DC; RIVERS/STREAM", "locations": "Antarctica", "north": -77.20215, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Cary, Stephen", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "NCBI GenBank", "repositories": "EMBL; KNB; NCBI GenBank", "science_programs": null, "south": -78.09343, "title": "Collaborative Research: Importance of Heterotrophic and Phototrophic N2 Fixation in the McMurdo Dry Valleys on Local, Regional and Landscape Scales", "uid": "p0000235", "west": 161.36062}, {"awards": "1142108 Koch, Paul", "bounds_geometry": "POLYGON((-180 -55.1,-168.1 -55.1,-156.2 -55.1,-144.3 -55.1,-132.4 -55.1,-120.5 -55.1,-108.6 -55.1,-96.7 -55.1,-84.8 -55.1,-72.9 -55.1,-61 -55.1,-61 -57.4,-61 -59.7,-61 -62,-61 -64.3,-61 -66.6,-61 -68.9,-61 -71.2,-61 -73.5,-61 -75.8,-61 -78.1,-72.9 -78.1,-84.8 -78.1,-96.7 -78.1,-108.6 -78.1,-120.5 -78.1,-132.4 -78.1,-144.3 -78.1,-156.2 -78.1,-168.1 -78.1,180 -78.1,178.47 -78.1,176.94 -78.1,175.41 -78.1,173.88 -78.1,172.35 -78.1,170.82 -78.1,169.29 -78.1,167.76 -78.1,166.23 -78.1,164.7 -78.1,164.7 -75.8,164.7 -73.5,164.7 -71.2,164.7 -68.9,164.7 -66.6,164.7 -64.3,164.7 -62,164.7 -59.7,164.7 -57.4,164.7 -55.1,166.23 -55.1,167.76 -55.1,169.29 -55.1,170.82 -55.1,172.35 -55.1,173.88 -55.1,175.41 -55.1,176.94 -55.1,178.47 -55.1,-180 -55.1))", "dataset_titles": "Southern Ocean Pinnipeds", "datasets": [{"dataset_uid": "000242", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Southern Ocean Pinnipeds", "url": "https://www.bco-dmo.org/project/726874"}], "date_created": "Wed, 28 Feb 2018 00:00:00 GMT", "description": "Building on previously funded NSF research, the use of paleobiological and paleogenetic data from mummified elephant seal carcasses found along the Dry Valleys and Victoria Land Coast in areas that today are too cold to support seal colonies (Mirougina leonina; southern elephant seals; SES) supports the former existence of these seals in this region. The occurrence and then subsequent disappearance of these SES colonies is consistent with major shifts in the Holocene climate to much colder conditions at the last ~1000 years BCE). \u003cbr/\u003e\u003cbr/\u003eFurther analysis of the preserved remains of three other abundant pinnipeds ? crabeater (Lobodon carciophagus), Weddell (Leptonychotes weddelli) and leopard (Hydrurga leptonyx) will be studied to track changes in their population size (revealed by DNA analysis) and their diet (studied via stable isotope analysis). Combined with known differences in life history, preferred ice habitat and ecosystem sensitivity among these species, this paleoclimate proxy data will be used to assess their exposure and sensitivity to climate change in the Ross Sea region during the past ~1-2,000 years", "east": -61.0, "geometry": "POINT(-128.15 -66.6)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; NOT APPLICABLE", "locations": null, "north": -55.1, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Koch, Paul; Costa, Daniel; Hoelzel, A. Rus", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -78.1, "title": "Collaborative Research: Exploring the Vulnerability of Southern Ocean Pinnipeds to Climate Change - An Integrated Approach", "uid": "p0000410", "west": 164.7}, {"awards": "1056396 Morgan-Kiss, Rachael", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Genetic sequence identifier: Accession Numbers: GU132860-GU132939; JN091926-JN091960; JQ9243533-JQ924384; KJ848331-KJ848439; KU196097-KU196166; PRJNA396917", "datasets": [{"dataset_uid": "000241", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Genetic sequence identifier: Accession Numbers: GU132860-GU132939; JN091926-JN091960; JQ9243533-JQ924384; KJ848331-KJ848439; KU196097-KU196166; PRJNA396917", "url": "https://www.ncbi.nlm.nih.gov/genbank/"}], "date_created": "Mon, 26 Feb 2018 00:00:00 GMT", "description": "This CAREER proposal will support an early career female PI to establish an integrated research and education program in the fields of polar biology and environmental microbiology, focusing on single-celled eukaryotes (protists) in high latitude ice-covered Antarctic lakes systems. Protists play important roles in energy flow and material cycling, and act as both primary producers (fixing inorganic carbon by photosynthesis) and consumers (preying on bacteria by phagotrophic digestion). The McMurdo Dry Valleys (MDV) located in Victoria Land, Antarctica, harbor microbial communities which are isolated in the unique aquatic ecosystem of perennially ice-capped lakes. The lakes support exclusively microbial consortia in chemically stratified water columns that are not influenced by seasonal mixing, allochthonous inputs, or direct human impact. This project will exploit permanently stratified biogeochemistry that is unique across the water columns of several MDV lakes to address gaps in our understanding of protist trophic function in aquatic food webs. The proposed research will examine (1) the impact of permanent biogeochemical gradients on protist trophic strategy, (2) the effect of major abiotic drivers (light and nutrients) on the distribution of two key mixotrophic and photoautotrophic protist species, and (3) the effect of episodic nutrient pulses on mixotroph communities in high latitude (ultraoligotrophic) MDV lakes versus low latitude (eutrophic) watersheds. The project will impact the fields of microbial ecology and environmental microbiology by combining results from field, laboratory and in situ incubation studies to synthesize new models for the protist trophic roles in the aquatic food web. The research component of this proposed project will be tightly integrated with the development of two new education activities designed to exploit the inherent excitement associated with polar biological research. The educational objectives are: 1) to establish a teaching module in polar biology in a core undergraduate course for microbiology majors; 2) to develop an instructional module to engage middle school girls in STEM disciplines. Undergraduates and middle school girls will also work with a doctoral student on his experiments in local Ohio watersheds.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Morgan-Kiss, Rachael", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "NCBI GenBank", "repositories": "NCBI GenBank", "science_programs": null, "south": -90.0, "title": "CAREER:Protist Nutritional Strategies in Permanently Stratified Antarctic Lakes", "uid": "p0000310", "west": -180.0}, {"awards": "0944307 Conway, Howard; 0944021 Brook, Edward J.; 0943466 Hawley, Robert", "bounds_geometry": "POLYGON((-163 -79,-162.8 -79,-162.6 -79,-162.4 -79,-162.2 -79,-162 -79,-161.8 -79,-161.6 -79,-161.4 -79,-161.2 -79,-161 -79,-161 -79.05,-161 -79.1,-161 -79.15,-161 -79.2,-161 -79.25,-161 -79.3,-161 -79.35,-161 -79.4,-161 -79.45,-161 -79.5,-161.2 -79.5,-161.4 -79.5,-161.6 -79.5,-161.8 -79.5,-162 -79.5,-162.2 -79.5,-162.4 -79.5,-162.6 -79.5,-162.8 -79.5,-163 -79.5,-163 -79.45,-163 -79.4,-163 -79.35,-163 -79.3,-163 -79.25,-163 -79.2,-163 -79.15,-163 -79.1,-163 -79.05,-163 -79))", "dataset_titles": "Roosevelt Island Borehole Firn temperatures; Roosevelt Island Borehole Optical Televiewer logs; Roosevelt Island Ice Core Time Scale and Associated Data; Roosevelt Island: Radar and GPS", "datasets": [{"dataset_uid": "601070", "doi": "10.15784/601070", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; GPS Data; Ice Velocity; Navigation; Radar; Roosevelt Island; Ross Sea", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island: Radar and GPS", "url": "https://www.usap-dc.org/view/dataset/601070"}, {"dataset_uid": "601085", "doi": "10.15784/601085", "keywords": "Antarctica; Borehole; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Records; Ice Fabric; Optical Images; Roosevelt Island; Snow/ice; Snow/Ice; Temperature", "people": "Clemens-Sewall, David; Hawley, Robert L.; Giese, Alexandra", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Borehole Firn temperatures", "url": "https://www.usap-dc.org/view/dataset/601085"}, {"dataset_uid": "601086", "doi": "10.15784/601086", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Roosevelt Island; Snow/ice; Snow/Ice", "people": "Hawley, Robert L.; Clemens-Sewall, David", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Borehole Optical Televiewer logs", "url": "https://www.usap-dc.org/view/dataset/601086"}, {"dataset_uid": "601359", "doi": "10.15784/601359", "keywords": "Antarctica; CO2; Ice Core; Roosevelt Island", "people": "Lee, James; Brook, Edward J.", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Ice Core Time Scale and Associated Data", "url": "https://www.usap-dc.org/view/dataset/601359"}], "date_created": "Fri, 16 Feb 2018 00:00:00 GMT", "description": "This award supports a project to use the Roosevelt Island ice core as a glaciological dipstick for the eastern Ross Sea. Recent attention has focused on the eastern Ross Embayment, where there are no geological constraints on ice thickness changes, due to the lack of protruding rock \"dipsticks\" where the ice sheet can leave datable records of high stands. Recent work has shown how dated ice cores can be used as dipsticks to derive ice-thickness histories. Partners from New Zealand and Denmark will extract an ice core from Roosevelt Island during the 2010-2011 and 2011-12 austral summers. Their science objective is to contribute to understanding of climate variability over the past 40kyr. The science goal of this project is not the climate record, but rather the history of deglaciation in the Ross Sea. The new history from the eastern Ross Sea will be combined with the glacial histories from the central Ross Sea (Siple Dome and Byrd) and existing and emerging histories from geologic and marine records along the western Ross Sea margin and will allow investigators to establish an updated, self-consistent model of the configuration and thickness of ice in the Ross Embayment during the LGM, and the timing of deglaciation. Results from this work will provide ground truth for new-generation ice-sheet models that incorporate ice streams and fast-flow dynamics. Realistic ice-sheet models are needed not only for predicting the response to future possible environments, but also for investigating past behaviors of ice sheets. This research contributes to the primary goals of the West Antarctic Ice Sheet Initiative as well as the IPY focus on ice-sheet history and dynamics. It also contributes to understanding spatial and temporal patterns of climate change and climate dynamics over the past 40kyr, one of the primary goals of the International Partnerships in Ice Core Sciences (IPICS). The project will help to develop the next generation of scientists and will contribute to the education and training of two Ph.D. students. All participants will benefit from the international collaboration, which will expose them to different field and laboratory techniques and benefit future collaborative work. All participants are involved in scientific outreach and undergraduate education, and are committed to fostering diversity. Outreach will be accomplished through regularly scheduled community and K-12 outreach events, talks and popular writing by the PIs, as well as through University press offices.", "east": -161.0, "geometry": "POINT(-162 -79.25)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "AMD; FIELD INVESTIGATION; Amd/Us; Deglaciation; USAP-DC; USA/NSF; NOT APPLICABLE; Ice Core; Not provided; Ross Sea Embayment", "locations": "Ross Sea Embayment", "north": -79.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard; Brook, Edward J.; Hawley, Robert L.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.5, "title": "Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island", "uid": "p0000272", "west": -163.0}, {"awards": "1246353 Anderson, John", "bounds_geometry": "POLYGON((-180 -74,-144.9 -74,-109.8 -74,-74.7 -74,-39.6 -74,-4.5 -74,30.6 -74,65.7 -74,100.8 -74,135.9 -74,171 -74,171 -74.3,171 -74.6,171 -74.9,171 -75.2,171 -75.5,171 -75.8,171 -76.1,171 -76.4,171 -76.7,171 -77,135.9 -77,100.8 -77,65.7 -77,30.6 -77,-4.5 -77,-39.6 -77,-74.7 -77,-109.8 -77,-144.9 -77,180 -77,180 -77,180 -77,180 -77,180 -77,180 -77,180 -77,180 -77,180 -77,180 -77,180 -77,180 -76.7,180 -76.4,180 -76.1,180 -75.8,180 -75.5,180 -75.2,180 -74.9,180 -74.6,180 -74.3,180 -74,180 -74,180 -74,180 -74,180 -74,180 -74,180 -74,180 -74,180 -74,180 -74,-180 -74))", "dataset_titles": "Circum-Antarctic grounding-line sinuosity; NBP1502A Cruise Core Data; NBP1502 Cruise Geophysics and underway data; Pennell Trough, Ross Sea bathymetry and glacial landforms", "datasets": [{"dataset_uid": "601484", "doi": "10.15784/601484", "keywords": "Antarctica; Bed Roughness; Bed Slope; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Pinning Points", "people": "Riverman, Kiya; Simkins, Lauren; Stearns, Leigh", "repository": "USAP-DC", "science_program": null, "title": "Circum-Antarctic grounding-line sinuosity", "url": "https://www.usap-dc.org/view/dataset/601484"}, {"dataset_uid": "601474", "doi": "10.15784/601474", "keywords": "Antarctica; Bathymetry; Elevation; Geomorphology; Glacial History; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marine Geoscience; NBP1502; Pennell Trough; Ross Sea; R/v Nathaniel B. Palmer", "people": "Prothro, Lindsay; Anderson, John; Eareckson, Elizabeth; Munevar Garcia, Santiago; Greenwood, Sarah; Simkins, Lauren", "repository": "USAP-DC", "science_program": null, "title": "Pennell Trough, Ross Sea bathymetry and glacial landforms", "url": "https://www.usap-dc.org/view/dataset/601474"}, {"dataset_uid": "601083", "doi": "10.15784/601083", "keywords": "Antarctica; Chemistry:sediment; Chemistry:Sediment; Geochronology; Marine Geoscience; Marine Sediments; NBP1502; R/v Nathaniel B. Palmer; Sediment Core", "people": "Simkins, Lauren; Anderson, John; Prothro, Lindsay", "repository": "USAP-DC", "science_program": null, "title": "NBP1502A Cruise Core Data", "url": "https://www.usap-dc.org/view/dataset/601083"}, {"dataset_uid": "000245", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1502 Cruise Geophysics and underway data", "url": "https://www.rvdata.us/search/cruise/NBP1502"}], "date_created": "Tue, 06 Feb 2018 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PI hypothesizes that bedforms found in the Central and Joides troughs can be interpreted as having been formed by rapid retreat, and possible collapse of an ice stream that occupied this area. To test this hypothesis, the PI proposes to conduct a detailed marine geological and geophysical survey of Central and Joides Troughs in the western Ross Sea. This project will bridge gaps between the small and isolated areas previously surveyed and will acquire a detailed sedimentological record of the retreating grounding line. The PI will reconstruct the retreat history of the Central and Joides troughs to century-scale resolution using radiocarbon dating methods and by looking at geomorphic features that are formed at regular time intervals. Existing multibeam, deep tow side-scan sonar, and core data will provide a framework for this research. The western Ross Sea is an ideal study area to investigate a single ice stream and the dynamics controlling its stability, including interactions between both East and West Antarctic Ice Sheets. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis proposal includes a post-doc, a graduate and two undergraduate students. The post-doc is involved with teaching an in-service K-12 teacher development and training course at Rice University for high-need teachers with a focus on curriculum enhancement. The project fosters collaboration for the PI and students with researchers at Louisiana State University and international colleagues at the Institute for Paleobiology at the Polish Academy of Sciences. The results from this project could lead to a better understanding of ice sheet and ice stream stability. This project will yield implications for society\u0027s understanding of climate change, as this work improves understanding of the behavior of ice sheets and their links to global climate.", "east": 179.99, "geometry": "POINT(175.495 -75.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e CARBON ANALYZERS", "is_usap_dc": true, "keywords": "AMD; Amd/Us; USAP-DC; USA/NSF; R/V NBP; NBP1502", "locations": null, "north": -74.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, John", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -77.0, "title": "Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum.", "uid": "p0000395", "west": 171.0}, {"awards": "0838735 Nitsche, Frank O.", "bounds_geometry": "POLYGON((-140 -68,-136 -68,-132 -68,-128 -68,-124 -68,-120 -68,-116 -68,-112 -68,-108 -68,-104 -68,-100 -68,-100 -68.75,-100 -69.5,-100 -70.25,-100 -71,-100 -71.75,-100 -72.5,-100 -73.25,-100 -74,-100 -74.75,-100 -75.5,-104 -75.5,-108 -75.5,-112 -75.5,-116 -75.5,-120 -75.5,-124 -75.5,-128 -75.5,-132 -75.5,-136 -75.5,-140 -75.5,-140 -74.75,-140 -74,-140 -73.25,-140 -72.5,-140 -71.75,-140 -71,-140 -70.25,-140 -69.5,-140 -68.75,-140 -68))", "dataset_titles": "Bathymetry compilation of Pine Island Bay, Amundsen Sea, Antarctica; OSO0910 Expedition Data", "datasets": [{"dataset_uid": "000525", "doi": "", "keywords": null, "people": null, "repository": "MGDS", "science_program": null, "title": "OSO0910 Expedition Data", "url": "https://www.marine-geo.org/tools/search/entry.php?id=OSO0910"}, {"dataset_uid": "000225", "doi": "", "keywords": null, "people": null, "repository": "MGDS", "science_program": null, "title": "Bathymetry compilation of Pine Island Bay, Amundsen Sea, Antarctica", "url": "http://dx.doi.org/10.1594/IEDA/320080"}], "date_created": "Fri, 26 Jan 2018 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The West Antarctic Ice Sheet is believed to be vulnerable to climate change as it is grounded below sea level, is drained by rapidly flowing ice streams and is fringed by floating ice shelves subject to melting by incursions of relatively warm Antarctic circumpolar water. Currently, the most rapidly thinning glaciers in Antarctica occur in the Amundsen and Bellingshausen Sea sectors. This study seeks to place the present day observations into a longer-term geological context over a broad scale by high-resolution swath bathymetric mapping of continental shelf sea floor features that indicate past ice presence and behavior. Gaps in existing survey coverage of glacial lineations and troughs indicating ice flow direction and paleo-grounding zone wedges over the Ross, Amundsen and Bellingshausen Sea sectors are targeted. The surveys will be conducted as part of the 2010 Icebreaker Oden science opportunity and will take advantage of the vessel?s state-of-the-art swath mapping system.\u003cbr/\u003e\u003cbr/\u003eBroader impacts:\u003cbr/\u003eThis activity will supplement and complement more focused regional studies by US, Swedish, UK, French, Japanese and Polish collaborators also sailing on the Oden. The PI will compile bathymetric data to be acquired by the Oden and other ships in the region over the duration of the project into the existing bathymetric data base. The compiled data set will be made publically available through the NSF founded Antarctic Multibeam Bathymetry and Geophysical Data Synthesis (AMBS) site. It will also be integrated into the GEBCO International Bathymetric Chart of the Southern Ocean (IBCSO) and so significantly improve the basis for ship navigation in the Pacific sector of the Southern Ocean. Undergraduate students will be involved in the research under supervision of the PI via the Lamont summer internship program. The PI is a young investigator and this will be his first NSF grant as a PI.", "east": -100.0, "geometry": "POINT(-120 -71.75)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES", "is_usap_dc": true, "keywords": "BATHYMETRY; SHIPS; Southern Ocean; Antarctica; Polar; GLACIERS/ICE SHEETS; R/V NBP", "locations": "Polar; Southern Ocean; Antarctica", "north": -68.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Nitsche, Frank O.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "MGDS", "repositories": "MGDS", "science_programs": null, "south": -75.5, "title": "Ice sheet Dynamics and Processes along the West Antarctic Continental Shelf", "uid": "p0010001", "west": -140.0}, {"awards": "1245899 Kowalewski, Douglas", "bounds_geometry": "POLYGON((-180 -70,-174 -70,-168 -70,-162 -70,-156 -70,-150 -70,-144 -70,-138 -70,-132 -70,-126 -70,-120 -70,-120 -71.5,-120 -73,-120 -74.5,-120 -76,-120 -77.5,-120 -79,-120 -80.5,-120 -82,-120 -83.5,-120 -85,-126 -85,-132 -85,-138 -85,-144 -85,-150 -85,-156 -85,-162 -85,-168 -85,-174 -85,180 -85,178 -85,176 -85,174 -85,172 -85,170 -85,168 -85,166 -85,164 -85,162 -85,160 -85,160 -83.5,160 -82,160 -80.5,160 -79,160 -77.5,160 -76,160 -74.5,160 -73,160 -71.5,160 -70,162 -70,164 -70,166 -70,168 -70,170 -70,172 -70,174 -70,176 -70,178 -70,-180 -70))", "dataset_titles": "Region Climate Model Output Plio-Pleistocene", "datasets": [{"dataset_uid": "601080", "doi": "10.15784/601080", "keywords": "Antarctica; Climate Model; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model; McMurdo; Paleoclimate; Ross Sea", "people": "Kowalewski, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Region Climate Model Output Plio-Pleistocene", "url": "https://www.usap-dc.org/view/dataset/601080"}], "date_created": "Tue, 16 Jan 2018 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to complement the ANDRILL marine record with a terrestrial project that will provide chronological control for past fluctuations of the West Antarctic Ice Sheet (WAIS) and alpine glaciers in McMurdo Sound. The project will develop high-resolution maps of drifts deposited from grounded marine-based ice and alpine glaciers on islands and peninsulas in McMurdo Sound. In addition, the PIs will acquire multi-clast/multi-nuclide cosmogenic analyses of these mapped drift sheets and alpine moraines and use regional climate modeling to shed light on the range of possible environmental conditions in the McMurdo region during periods of grounded ice expansion and recession. The PIs will make use of geological records for ice sheet and alpine glacier fluctuations preserved on the flanks of Mount Discovery, Black Island, and Brown Peninsula. Drifts deposited from grounded, marine-based ice will yield spatial constraints for former advances and retreats of the WAIS. Moraines from alpine glaciers, hypothesized to be of interglacial origin, could yield a first-order record of hydrologic change in the region. Synthesizing the field data, the team proposes to improve the resolution of existing regional-scale climate models for the Ross Embayment. The overall approach and anticipated results will provide the first steps towards linking the marine and terrestrial records in this critical sector of Antarctica.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eResults from the proposed work will be integrated with outreach programs at Boston University, Columbia University, and Worcester State University. The team will actively collaborate with the American Museum of Natural History to feature this project prominently in museum outreach. The team will also include a PolarTREC teacher as a member of the research team. The geomorphological results will be presented in 3D at Boston University?s Antarctic Digital Image Analyses Lab. The research will form the basis of a PhD dissertation at Boston University.", "east": -120.0, "geometry": "POINT(-160 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -70.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kowalewski, Douglas", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Collaborative Research: West Antarctic Ice Sheet stability, Alpine Glaciation, and Climate Variability: a Terrestrial Perspective from Cosmogenic-nuclide Dating in McMurdo Sound", "uid": "p0000391", "west": 160.0}, {"awards": "1115245 McKnight, Diane", "bounds_geometry": "POLYGON((160.5 -77.35,160.83 -77.35,161.16 -77.35,161.49 -77.35,161.82 -77.35,162.15 -77.35,162.48 -77.35,162.81 -77.35,163.14 -77.35,163.47 -77.35,163.8 -77.35,163.8 -77.4,163.8 -77.45,163.8 -77.5,163.8 -77.55,163.8 -77.6,163.8 -77.65,163.8 -77.7,163.8 -77.75,163.8 -77.8,163.8 -77.85,163.47 -77.85,163.14 -77.85,162.81 -77.85,162.48 -77.85,162.15 -77.85,161.82 -77.85,161.49 -77.85,161.16 -77.85,160.83 -77.85,160.5 -77.85,160.5 -77.8,160.5 -77.75,160.5 -77.7,160.5 -77.65,160.5 -77.6,160.5 -77.55,160.5 -77.5,160.5 -77.45,160.5 -77.4,160.5 -77.35))", "dataset_titles": "McMurdo Dry Valleys LTER data at EDI Data Portal", "datasets": [{"dataset_uid": "000204", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "McMurdo Dry Valleys LTER data at EDI Data Portal", "url": "https://portal.edirepository.org/nis/browseServlet?searchValue=MCM "}], "date_created": "Mon, 08 Jan 2018 00:00:00 GMT", "description": "The McMurdo Dry Valleys (MDV) is a polar desert on the coast of East Antarctica, a region that has not yet experienced climate warming. The McMurdo Dry Valleys Long Term Ecological Research (MCMLTER) project has documented the ecological responses of the glacier, soil, stream and lake ecosystems in the MDV during a cooling trend (from 1986 to 2000) which was associated with the depletion of atmospheric ozone. In the past decade, warming events with strong katabatic winds occurred during two summers and the resulting high streamflows and sediment deposition changed the dry valley landscape, possibly presaging conditions that will occur when the ozone hole recovers. In anticipation of future warming in Antarctica, the overarching hypothesis of the proposed project is: Climate warming in the McMurdo Dry Valley ecosystem will amplify connectivity among landscape units leading to enhanced coupling of nutrient cycles across landscapes, and increased biodiversity and productivity within the ecosystem. Warming in the MDV is hypothesized to act as a slowly developing, long-term press of warmer summers, upon which transient pulse events of high summer flows and strong katabatic winds will be overprinted. Four specific hypotheses address the ways in which pulses of water and wind will influence contemporary and future ecosystem structure, function and connectivity. Because windborne transport of biota is a key aspect of enhanced connectivity from katabatic winds, new monitoring will include high-resolution measurements of aeolian particle flux. Importantly, integrative genomics will be employed to understand the responses of specific organisms to the increased connectivity. The project will also include a novel social science component that will use environmental history to examine interactions between human activity, scientific research, and environmental change in the MDV over the past 100 years. To disseminate this research broadly, MCM scientists will participate in a wide array of outreach efforts ranging from presentations in K-12 classrooms to bringing undergraduates and teachers to the MDV to gain research experience. Planned outreach programs will build upon activities conducted during the International Polar Year (2007-2008), which include development of an interactive DVD for high school students and teachers and publication of a children\u0027s book in the LTER Schoolyard Book Series. A teacher\u0027s edition of the book with a CD containing lesson plans will be distributed. The project will develop programs for groups traditionally underrepresented in science arenas by publishing some outreach materials in Spanish.", "east": 163.8, "geometry": "POINT(162.15 -77.6)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.35, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "McKnight, Diane; Gooseff, Michael N.", "platforms": "Not provided", "repo": "LTER", "repositories": "LTER", "science_programs": "LTER", "south": -77.85, "title": "Increased Connectivity in a Polar Desert Resulting from Climate Warming: McMurdo Dry Valley LTER Program", "uid": "p0000301", "west": 160.5}, {"awards": "1543245 Rynearson, Tatiana", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP1701; NCBI Popset of 43 Southern Ocean diatom isolates, including accessions ON678208.1 - ON678250.1; Specific growth rate measurements for 43 Southern Ocean diatoms", "datasets": [{"dataset_uid": "002661", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1701", "url": "https://www.rvdata.us/search/cruise/NBP1701"}, {"dataset_uid": "601586", "doi": "10.15784/601586", "keywords": "Antarctica; Biota; NBP1701; Phytoplankton; R/v Nathaniel B. Palmer; Specific Growth Rate; Thermal Optimum Temperature", "people": "Bishop, Ian", "repository": "USAP-DC", "science_program": null, "title": "Specific growth rate measurements for 43 Southern Ocean diatoms", "url": "https://www.usap-dc.org/view/dataset/601586"}, {"dataset_uid": "001369", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1701"}, {"dataset_uid": "200328", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "NCBI Popset of 43 Southern Ocean diatom isolates, including accessions ON678208.1 - ON678250.1", "url": "https://www.ncbi.nlm.nih.gov/popset/?term=2248543458"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "The research will examine how diatoms (an important group of plankton in the Southern Ocean) adapt to environmental change. Diatoms will be sampled from different regions of the Southern Ocean, including the Drake Passage, the Pacific Sector of the Southern Ocean and the Ross Sea and examined to determine the range of genetic variation among diatoms in these regions. Experiments on a range of diatoms will be conducted in home laboratories and will be aimed at measuring shifts in physiological capacities over many generations in response to directional changes in the environment (temperature and pH). The information on the genetic diversity of field populations combined with information on potential rates of adaptability and genome changes will provide insight into ways in which polar marine diatoms populations may respond to environmental changes that may occur in surface oceans in the future or may have occurred during past climate conditions. Such information allows better modeling of biogeochemical cycles in the ocean as well as improves our abilities to interpret records of past ocean conditions. The project will support a doctoral student and a postdoctoral researcher as well as several undergraduate students. These scientists will learn the fundamentals of experimental evolution, a skill set that is being sought in the fields of biology and oceanography. The project also includes a collaboration with the Metcalf Institute for Marine and Environmental Reporting that will design and facilitate a session focused on current research related to evolution and climate change to be held at the annual conference of the National Association of Science Writers (NASW). \u003cbr/\u003e\u003cbr/\u003eBoth physiological and genetic variation are key parameters for understanding evolutionary processes in phytoplankton but they are essentially unknown for Southern Ocean diatoms. The extent to which these two factors determine plasticity and adaptability in field populations and the interaction between them will influence how and whether cold-adapted diatoms can respond to changing environments. This project includes a combination of field work to identify genetic diversity within diatoms using molecular approaches and experiments in the lab to assess the range of physiological variation in contemporary populations of diatoms and evolution experiments in the lab to assess how the combination of genetic diversity and physiological variation influence the evolutionary potential of diatoms under a changing environment. This research will uncover general relationships between physiological variation, genetic diversity, and evolutionary potential that may apply across microbial taxa and geographical regions, substantially improving efforts to predict shifts in marine ecosystems. Results from this study can be integrated into developing models that incorporate evolution to predict ecosystem changes under future climate change scenarios.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "USAP-DC; NBP1701; R/V NBP; AMD; USA/NSF; Amd/Us; DIATOMS", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rynearson, Tatiana; Bishop, Ian", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "NCBI; R2R; USAP-DC", "science_programs": null, "south": null, "title": "NSFGEO-NERC: Evolutionary Response of Southern Ocean Diatoms to Environmental Change", "uid": "p0000850", "west": null}, {"awards": "1143981 Domack, Eugene", "bounds_geometry": "POLYGON((-69.9517 -52.7581,-69.02971 -52.7581,-68.10772 -52.7581,-67.18573 -52.7581,-66.26374 -52.7581,-65.34175 -52.7581,-64.41976 -52.7581,-63.49777 -52.7581,-62.57578 -52.7581,-61.65379 -52.7581,-60.7318 -52.7581,-60.7318 -54.31551,-60.7318 -55.87292,-60.7318 -57.43033,-60.7318 -58.98774,-60.7318 -60.54515,-60.7318 -62.10256,-60.7318 -63.65997,-60.7318 -65.21738,-60.7318 -66.77479,-60.7318 -68.3322,-61.65379 -68.3322,-62.57578 -68.3322,-63.49777 -68.3322,-64.41976 -68.3322,-65.34175 -68.3322,-66.26374 -68.3322,-67.18573 -68.3322,-68.10772 -68.3322,-69.02971 -68.3322,-69.9517 -68.3322,-69.9517 -66.77479,-69.9517 -65.21738,-69.9517 -63.65997,-69.9517 -62.10256,-69.9517 -60.54515,-69.9517 -58.98774,-69.9517 -57.43033,-69.9517 -55.87292,-69.9517 -54.31551,-69.9517 -52.7581))", "dataset_titles": "Expedition Data; Processed Camera Images acquired during the Laurence M. Gould expedition LMG1311", "datasets": [{"dataset_uid": "000402", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1702"}, {"dataset_uid": "601311", "doi": "10.15784/601311", "keywords": "Antarctica; Antarctic Peninsula; Benthic Images; Camera; LARISSA; LMG1311; Marine Geoscience; Photo; Photo/video; Photo/Video; R/v Laurence M. Gould", "people": "Domack, Eugene Walter", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Processed Camera Images acquired during the Laurence M. Gould expedition LMG1311", "url": "https://www.usap-dc.org/view/dataset/601311"}, {"dataset_uid": "001366", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1702"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "This project aims to identify which portions of the glacial cover in the Antarctic Peninsula are losing mass to the ocean. This is an important issue to resolve because the Antarctic Peninsula is warming at a faster rate than any other region across the earth. Even though glaciers across the Antarctic Peninsula are small, compared to the continental ice sheet, defining how rapidly they respond to both ocean and atmospheric temperature rise is critical. It is critical because it informs us about the exact mechanisms which regulate ice flow and melting into the ocean. For instance, after the break- up of the Larsen Ice Shelf in 2002 many glaciers began to flow rapidly into the sea. Measuring how much ice was involved is difficult and depends upon accurate estimates of volume and area. One way to increase the accuracy of our estimates is to measure how fast the Earth\u0027s crust is rebounding or bouncing back, after the ice has been removed. This rebound effect can be measured with very precise techniques using instruments locked into ice free bedrock surrounding the area of interest. These instruments are monitored by a set of positioning satellites (the Global Positioning System or GPS) in a continuous fashion. Of course the movement of the Earth\u0027s bedrock relates not only to the immediate response but also the longer term rate that reflects the long vanished ice masses that once covered the entire Antarctic Peninsula?at the time of the last glaciation. These rebound measurements can, therefore, also tell us about the amount of ice which covered the Antarctic Peninsula thousands of years ago. Glacial isostatic rebound is one of the complicating factors in allowing us to understand how much the larger ice sheets are losing today, something that can be estimated by satellite techniques but only within large errors when the isostatic (rebound) correction is unknown.\u003cbr/\u003e\u003cbr/\u003eThe research proposed consists of maintaining a set of six rebound stations until the year 2016, allowing for a longer time series and thus more accurate estimates of immediate elastic and longer term rebound effects. It also involves the establishment of two additional GPS stations that will focus on constraining the \"bull\u0027s eye\" of rebound suggested by measurements over the past two years. In addition, several more geologic data points will be collected that will help to reconstruct the position of the ice sheet margin during its recession from the full ice sheet of the last glacial maximum. These will be based upon the coring of marine sediment sequences now recognized to have been deposited along the margins of retreating ice sheets and outlets. Precise dating of the ice margin along with the new and improved rebound data will help to constrain past ice sheet configurations and refine geophysical models related to the nature of post glacial rebound. Data management will be under the auspices of the UNAVCO polar geophysical network or POLENET and will be publically available at the time of station installation. This project is a small scale extension of the ongoing LARsen Ice Shelf, Antarctica Project (LARISSA), an IPY (International Polar Year)-funded interdisciplinary study aimed at understanding earth system connections related to the Larsen Ice Shelf and the northern Antarctic Peninsula.", "east": -60.7318, "geometry": "POINT(-65.34175 -60.54515)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e SEISMIC REFLECTION PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "LMG1702; R/V LMG", "locations": null, "north": -52.7581, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Kohut, Josh; Domack, Eugene Walter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -68.3322, "title": "Continuation of the LARISSA Continuous GPS Network in View of Observed Dynamic Response to Antarctic Peninsula Ice Mass Balance and Required Geologic Constraints", "uid": "p0000233", "west": -69.9517}, {"awards": "1141939 Lubin, Dan", "bounds_geometry": "POLYGON((-167.0365 -77.5203,-166.96385 -77.5203,-166.8912 -77.5203,-166.81855 -77.5203,-166.7459 -77.5203,-166.67325 -77.5203,-166.6006 -77.5203,-166.52795 -77.5203,-166.4553 -77.5203,-166.38265 -77.5203,-166.31 -77.5203,-166.31 -77.52527,-166.31 -77.53024,-166.31 -77.53521,-166.31 -77.54018,-166.31 -77.54515,-166.31 -77.55012,-166.31 -77.55509,-166.31 -77.56006,-166.31 -77.56503,-166.31 -77.57,-166.38265 -77.57,-166.4553 -77.57,-166.52795 -77.57,-166.6006 -77.57,-166.67325 -77.57,-166.7459 -77.57,-166.81855 -77.57,-166.8912 -77.57,-166.96385 -77.57,-167.0365 -77.57,-167.0365 -77.56503,-167.0365 -77.56006,-167.0365 -77.55509,-167.0365 -77.55012,-167.0365 -77.54515,-167.0365 -77.54018,-167.0365 -77.53521,-167.0365 -77.53024,-167.0365 -77.52527,-167.0365 -77.5203))", "dataset_titles": "Shortwave Spectroradiometer Data from Ross Island, Antarctica", "datasets": [{"dataset_uid": "601074", "doi": "10.15784/601074", "keywords": "Antarctica; Atmosphere; Meteorology; Radiosounding; Ross Island", "people": "Lubin, Dan", "repository": "USAP-DC", "science_program": null, "title": "Shortwave Spectroradiometer Data from Ross Island, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601074"}], "date_created": "Wed, 20 Dec 2017 00:00:00 GMT", "description": "Antarctic clouds constitute an important parameter of the surface radiation budget and thus play a significant role in Antarctic climate and climate change. The variability in, and long term trends of, cloud optical and microphysical properties are therefore fundamental in parameterizing the mixed phase (water-snow-ice) coastal Antarctic stratiform clouds experienced around the continent.\u003cbr/\u003e\u003cbr/\u003eUsing a spectoradiometer that covers the wavelength range of 350 to 2200nm, the downwelled spectral irradiance at the earth surface (Ross Island) will be used to retrieve the optical depth, thermodynamic phase, liquid water droplet effective radius, and ice-cloud effective particle size of overhead clouds, at hourly intervals and for an austral summer season (Oct-March). Based on the very limited data sets that exist for the maritime Antarctic, expectations are that Ross Island (Lat 78 S) should exhibit clouds with:\u003cbr/\u003ea) An abundance of supercooled liquid water, and related mixed-phase cloud processes\u003cbr/\u003eb) Cloud nucleation from year round biogenic and oceanic sources, in an otherwise pristine environment\u003cbr/\u003ec) Simple cloud geometries of predominantly stratiform cloud decks\u003cbr/\u003e\u003cbr/\u003eIncreased understanding of the cloud properties in the region of the main USAP base, McMurdo station is also relevant to operational weather forecasting relevant to aviation. A range of educational and outreach activities are associate with the project, including provision of workshops for high school teachers will be carried out.", "east": -166.31, "geometry": "POINT(-166.67325 -77.54515)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; USAP-DC", "locations": null, "north": -77.5203, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Lubin, Dan", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.57, "title": "Antarctic Cloud Physics: Fundamental Observations from Ross Island", "uid": "p0000327", "west": -167.0365}, {"awards": "1543452 Blankenship, Donald", "bounds_geometry": "POLYGON((90 -64,97 -64,104 -64,111 -64,118 -64,125 -64,132 -64,139 -64,146 -64,153 -64,160 -64,160 -64.6,160 -65.2,160 -65.8,160 -66.4,160 -67,160 -67.6,160 -68.2,160 -68.8,160 -69.4,160 -70,153 -70,146 -70,139 -70,132 -70,125 -70,118 -70,111 -70,104 -70,97 -70,90 -70,90 -69.4,90 -68.8,90 -68.2,90 -67.6,90 -67,90 -66.4,90 -65.8,90 -65.2,90 -64.6,90 -64))", "dataset_titles": "EAGLE/ICECAP II GEOPHYSICAL OBSERVATIONS (SURFACE AND BED ELEVATION, ICE THICKNESS, GRAVITY DISTURBANCE AND MAGNETIC ANOMALIES); EAGLE/ICECAP II INSTRUMENT MEASUREMENTS (LASER, MAGNETICS and POSITIONING); EAGLE/ICECAP II RADARGRAMS; EAGLE/ICECAP II Raw data (gps, raw serial packet data, raw radar records, gravimeter data and camera images); ICECAP Basal Interface Specularity Content Profiles: IPY and OIB", "datasets": [{"dataset_uid": "200043", "doi": "http://dx.doi.org/doi:10.26179/5bcff4afc287d", "keywords": null, "people": null, "repository": "AADC", "science_program": null, "title": "EAGLE/ICECAP II RADARGRAMS", "url": "https://data.aad.gov.au/metadata/records/AAS_4346_EAGLE_ICECAP_LEVEL2_RADAR_DATA"}, {"dataset_uid": "200044", "doi": "https://dx.doi.org/10.26179/5bbedd001756b", "keywords": null, "people": null, "repository": "AADC", "science_program": null, "title": "EAGLE/ICECAP II Raw data (gps, raw serial packet data, raw radar records, gravimeter data and camera images)", "url": "https://data.aad.gov.au/metadata/records/AAS_4346_EAGLE_ICECAP_LEVEL0_RAW_DATA"}, {"dataset_uid": "601371", "doi": "10.15784/601371", "keywords": "Antarctica; East Antarctica; ICECAP; Ice Penetrating Radar; Radar Echo Sounder; Radar Echo Sounding; Subglacial Hydrology", "people": "Greenbaum, Jamin; Schroeder, Dustin; Young, Duncan A.; Blankenship, Donald D.; Roberts, Jason; Siegert, Martin; van Ommen, Tas", "repository": "USAP-DC", "science_program": null, "title": "ICECAP Basal Interface Specularity Content Profiles: IPY and OIB", "url": "https://www.usap-dc.org/view/dataset/601371"}, {"dataset_uid": "200042", "doi": "http://dx.doi.org/doi:10.26179/5bcfef4e3a297", "keywords": null, "people": null, "repository": "AADC", "science_program": null, "title": "EAGLE/ICECAP II INSTRUMENT MEASUREMENTS (LASER, MAGNETICS and POSITIONING)", "url": "https://data.aad.gov.au/metadata/records/AAS_4346_EAGLE_ICECAP_Level1B_AEROGEOPHYSICS"}, {"dataset_uid": "200041", "doi": "https://doi.org/10.26179/5bcfffdabcf92", "keywords": null, "people": null, "repository": "AADC", "science_program": null, "title": "EAGLE/ICECAP II GEOPHYSICAL OBSERVATIONS (SURFACE AND BED ELEVATION, ICE THICKNESS, GRAVITY DISTURBANCE AND MAGNETIC ANOMALIES)", "url": "https://data.aad.gov.au/metadata/records/AAS_4346_EAGLE_ICECAP_LEVEL2_AEROGEOPHYSICS"}], "date_created": "Tue, 05 Dec 2017 00:00:00 GMT", "description": "Previous studies of the Indo-Pacific region of Antarctica show that the margin of the ice sheet in this region has advanced and retreated into deep interior basins many times in the past. The apparent instability of this region makes it an important target for study in terms of understanding the future of the East Antarctic ice sheet and sea level rise. This project will study a number of processes that control the ice-shelf stability of this region, with the aim of improving projections of the rate and magnitude of future sea-level rise. This project will engage a range of students and train this next generation of scientists in the complex, interdisciplinary issue of ice-ocean interaction. The project will integrate geophysical data collected from aircraft over three critical sections of the East Antarctic grounding line (Totten Glacier, Denman Glacier, and Cook Ice Shelf) with an advanced ocean model. Using Australian and French assets, the team will collect new data around Denman Glacier and Cook Ice Shelf whereas analysis of Totten Glacier will be based on existing data. The project will assess three hypotheses to isolate the processes that drive the differences in observed grounding line thinning among these three glaciers: 1. bathymetry and large-scale ocean forcing control cavity circulation; 2. ice-shelf draft and basal morphology control cavity circulation; 3. subglacial freshwater input across the grounding line controls cavity circulation. The key outcomes of this new project will be to: 1. evaluate of ice-ocean coupling in areas of significant potential sea-level contribution; 2. relate volume changes of grounded and floating ice to regional oceanic heat transport and sub-ice shelf ocean dynamics in areas of significant potential sea-level and meridional overturning circulation impacts; and 3. improve boundary conditions to evaluate mass, heat, and freshwater budgets of East Antarctica\u0027s continental margins.", "east": 160.0, "geometry": "POINT(125 -67)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e MAGNETIC FIELD/ELECTRIC FIELD INSTRUMENTS \u003e MAGNETOMETERS \u003e GEOMET 823A; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS", "is_usap_dc": true, "keywords": "BT-67; Antarctica; GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHY; USAP-DC; SEAFLOOR TOPOGRAPHY; GRAVITY ANOMALIES; MAGNETIC ANOMALIES; Polar; Sea Floor", "locations": "Antarctica; Sea Floor; Polar", "north": -64.0, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Young, Duncan A.; Grima, Cyril; Blankenship, Donald D.", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e BT-67", "repo": "AADC", "repositories": "AADC; USAP-DC", "science_programs": null, "south": -70.0, "title": "East Antarctic Grounding Line Experiment (EAGLE)", "uid": "p0000254", "west": 90.0}, {"awards": "1344348 Mikucki, Jill; 1344349 Tulaczyk, Slawek", "bounds_geometry": null, "dataset_titles": "2011 Time-domain ElectroMagnetics data for McMurdo Dry Valleys; Marinobacter lipolyticus BF04_CF-4 genomic scaffold, whole genome shotgun sequence; Marinobacter sp. BF14_3D 16S ribosomal RNA gene, partial sequence", "datasets": [{"dataset_uid": "601071", "doi": "10.15784/601071", "keywords": "Antarctica; Dry Valleys; Electromagnetic Data; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; McMurdo", "people": "Tulaczyk, Slawek", "repository": "USAP-DC", "science_program": null, "title": "2011 Time-domain ElectroMagnetics data for McMurdo Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/601071"}, {"dataset_uid": "000196", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Marinobacter sp. BF14_3D 16S ribosomal RNA gene, partial sequence", "url": "https://www.ncbi.nlm.nih.gov/nuccore/KX364066"}, {"dataset_uid": "000197", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Marinobacter lipolyticus BF04_CF-4 genomic scaffold, whole genome shotgun sequence", "url": "https://www.ncbi.nlm.nih.gov/nuccore?term=PRJNA165567"}], "date_created": "Wed, 08 Nov 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe MCM-SkyTEM project mapped resistivity in the McMurdo Dry Valleys and at Cape Barne on the Ross Island during the 2011-12 austral season using an airborne transient electromagnetic method. The SkyTEM system is mounted to a helicopter enabling a broad geophysical survey of subsurface resistivity structure over terrain that is inaccessible to traditional ground-based methods. Resistivity measurements obtained distinguish between highly resistive geologic materials such as glacier ice, bedrock and permafrost, and conductive materials such as unfrozen sediments or permafrost with liquid brine to depths of about 300 m. The PIs request funding to derive data products relevant to physical and chemical conditions in potential subsurface microbial habitats of the McMurdo Dry Valleys, similar cold regions on Earth and other planetary bodies. They will use these data products to characterize the hydrologic history of McMurdo Dry Valleys as well as the subsurface hydrologic connectivity in the region to investigate the implications for nutrient and microbial transport. The PIs will make these data products accessible to the research community. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003ePolar microbial habitats are of high societal and scientific interest because they represent important testing grounds for the limits of life on Earth and other planetary bodies. Project deliverables will include teaching aids for undergraduate and graduate students. Two Ph.D. students will obtain advanced research training as part of this project. The PIs and students on this project will also engage in informal public outreach opportunities by presenting at local K-12 schools and reaching out to local media outlets on stories relating to SkyTEM research.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Integrated System Science", "paleo_time": null, "persons": "Tulaczyk, Slawek; Mikucki, Jill", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "NCBI GenBank; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: EAGER: Processing, Interpretation and Dissemination of the Proof-of-Concept Transient Electromagnetic Survey of the McMurdo Dry Valleys Region", "uid": "p0000329", "west": null}, {"awards": "1043784 Schwartz, Susan", "bounds_geometry": "POLYGON((-160 -79,-158 -79,-156 -79,-154 -79,-152 -79,-150 -79,-148 -79,-146 -79,-144 -79,-142 -79,-140 -79,-140 -79.3,-140 -79.6,-140 -79.9,-140 -80.2,-140 -80.5,-140 -80.8,-140 -81.1,-140 -81.4,-140 -81.7,-140 -82,-142 -82,-144 -82,-146 -82,-148 -82,-150 -82,-152 -82,-154 -82,-156 -82,-158 -82,-160 -82,-160 -81.7,-160 -81.4,-160 -81.1,-160 -80.8,-160 -80.5,-160 -80.2,-160 -79.9,-160 -79.6,-160 -79.3,-160 -79))", "dataset_titles": "PASSCAL experiment 201205 (full data link not provided)", "datasets": [{"dataset_uid": "000194", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "PASSCAL experiment 201205 (full data link not provided)", "url": "http://ds.iris.edu/ds/nodes/dmc/"}], "date_created": "Tue, 07 Nov 2017 00:00:00 GMT", "description": "This award provides support for \"Investigating (Un)Stable Sliding of Whillans Ice Stream and Subglacial Water Dynamics Using Borehole Seismology: A proposed Component of the Whillans Ice Stream Subglacial Access and Research Drilling\" from the Antarctic Integrated Systems Science (AISS) program in the Office of Polar Programs at NSF. The project will use the sounds naturally produced by the ice and subglacial water to understand the glacial dynamics of the Whillans Ice Stream located adjacent to the Ross Ice Shelf in Antarctica.\u003cbr/\u003e\u003cbr/\u003eIntellectual Merit: The transformative component of the project is that in addition to passive surface seismometers, the team will deploy a series of borehole seismometers. Englacial placement of the seismometers has not been done before, but is predicted to provide much better resolution (detection of smaller scale events as well as detection of a much wider range of frequencies) of the subglacial dynamics. In conjunction with the concurrent WISSARD (Whillans Ice Stream Subglacial Access and Research Drilling) project the team will be able to tie subglacial processes to temporal variations in ice stream dynamics and mass balance of the ice stream. The Whillans Ice Stream experiences large changes in ice velocity in response to tidally triggered stick-slip cycles as well as periodic filling and draining of subglacial Lake Whillans. The overall science goals include: improved understanding of basal sliding processes and role of sticky spots, subglacial lake hydrology, and dynamics of small earthquakes and seismic properties of ice and firn.\u003cbr/\u003e\u003cbr/\u003eBroader Impact: Taken together, the research proposed here will provide information on basal controls of fast ice motion which has been recognized by the IPCC as necessary to make reliable predictions of future global sea-level rise. The information collected will therefore have broader implications for global society. The collected information will also be relevant to a better understanding of earthquakes. For outreach the project will work with the overall WISSARD outreach coordinator to deliver information to three audiences: the general public, middle school teachers, and middle school students. The project also provides funding for training of graduate students, and includes a female principal investigator.", "east": -140.0, "geometry": "POINT(-150 -80.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -79.0, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Schwartz, Susan; Tulaczyk, Slawek", "platforms": "Not provided", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -82.0, "title": "Investigating (Un)Stable Sliding of Whillians Ice Stream and Subglacial Water Dynamics Using Borehole Seismology: A Proposed Component of WISSARD", "uid": "p0000393", "west": -160.0}, {"awards": "1460449 Goehring, Brent; 1341420 Balco, Gregory; 1341364 Todd, Claire", "bounds_geometry": "POLYGON((164.08 -74.6,164.0842 -74.6,164.0884 -74.6,164.0926 -74.6,164.0968 -74.6,164.101 -74.6,164.1052 -74.6,164.1094 -74.6,164.1136 -74.6,164.1178 -74.6,164.122 -74.6,164.122 -74.6023,164.122 -74.6046,164.122 -74.6069,164.122 -74.6092,164.122 -74.6115,164.122 -74.6138,164.122 -74.6161,164.122 -74.6184,164.122 -74.6207,164.122 -74.623,164.1178 -74.623,164.1136 -74.623,164.1094 -74.623,164.1052 -74.623,164.101 -74.623,164.0968 -74.623,164.0926 -74.623,164.0884 -74.623,164.0842 -74.623,164.08 -74.623,164.08 -74.6207,164.08 -74.6184,164.08 -74.6161,164.08 -74.6138,164.08 -74.6115,164.08 -74.6092,164.08 -74.6069,164.08 -74.6046,164.08 -74.6023,164.08 -74.6))", "dataset_titles": "Interface to observational data associated with exposure-age measurements and resulting calculated ages. Dynamic content, updated.", "datasets": [{"dataset_uid": "200196", "doi": null, "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Interface to observational data associated with exposure-age measurements and resulting calculated ages. Dynamic content, updated.", "url": "https://version2.ice-d.org/antarctica/nsf/"}], "date_created": "Wed, 18 Oct 2017 00:00:00 GMT", "description": "The investigators will map glacial deposits and date variations in glacier variability at several ice-free regions in northern Victoria Land, Antarctica. These data will constrain the nature and timing of past ice thickness changes for major glaciers that drain into the northwestern Ross Sea. This is important because during the Last Glacial Maximum (15,000 - 18,000 years ago) these glaciers were most likely flowing together with grounded ice from both the East and West Antarctic Ice Sheets that expanded across the Ross Sea continental shelf to near the present shelf edge. Thus, the thickness of these glaciers was most likely controlled in part by the extent and thickness of the Ross Sea ice sheet and ice shelf. The data the PIs propose to collect can provide constraints on the position of the grounding line in the western Ross Sea during the Last Glacial Maximum, the time that position was reached, and ice thickness changes that occurred after that time. The primary intellectual merit of this project will be to improve understanding of a period of Antarctic ice sheet history that is relatively unconstrained at present and also potentially important in understanding past ice sheet-sea level interactions. \u003cbr/\u003e\u003cbr/\u003eThis proposal will support an early career researcher\u0027s ongoing program of undergraduate education and research that is building a socio-economically diverse student body with students from backgrounds underrepresented in the geosciences. This proposal will also bring an early career researcher into Antarctic research.", "east": 164.122, "geometry": "POINT(164.101 -74.6115)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; Cosmogenic Dating; Exposure Age; LABORATORY; NOT APPLICABLE; Amd/Us; Ross Sea", "locations": "Ross Sea", "north": -74.6, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Goehring, Brent; Balco, Gregory; Todd, Claire", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "ICE-D", "repositories": "ICE-D", "science_programs": null, "south": -74.623, "title": "Collaborative Research: Terrestrial Exposure-Age Constraints on the last Glacial Maximum Extent of the Antarctic Ice Sheet in the Western Ross Sea", "uid": "p0000306", "west": 164.08}, {"awards": "1142007 Kurbatov, Andrei", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic Ice Core Tephra Analysis; Antarctic Tephra Data Base AntT static web site", "datasets": [{"dataset_uid": "601038", "doi": "10.15784/601038", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Intracontinental Magmatism; IntraContinental Magmatism; Tephra", "people": "Kurbatov, Andrei V.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Antarctic Ice Core Tephra Analysis", "url": "https://www.usap-dc.org/view/dataset/601038"}, {"dataset_uid": "601052", "doi": "10.15784/601052", "keywords": "Antarctica; Geochemistry; Geochronology; Glaciology; Intracontinental Magmatism; IntraContinental Magmatism; Sample/collection Description; Sample/Collection Description; Tephra", "people": "Dunbar, Nelia; Kurbatov, Andrei V.", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Tephra Data Base AntT static web site", "url": "https://www.usap-dc.org/view/dataset/601052"}], "date_created": "Fri, 06 Oct 2017 00:00:00 GMT", "description": "Many key questions in climate research (e.g. relative timing of climate events in different geographic areas, climate-forcing mechanisms, natural threshold levels in the climate system) are dependent on accurate reconstructions of the temporal and spatial distribution of past rapid climate change events in continental, atmospheric, marine and polar realms. This collaborative interdisciplinary research project aims to consolidate, into a single user-friendly database, information about volcanic products detected in Antarctica. By consolidating information about volcanic sources, and physical and geochemical characteristics of volcanic products, this systematic data collection approach will improve the ability of researchers to identify volcanic ash, or tephra, from specific volcanic eruptions that may be spread over large areas in a geologically instantaneous amount of time. Development of this database will assist in the identification and cross-correlation of time intervals in various paleoclimate archives that contain volcanic layers from often unknown sources. The AntT project relies on a cyberinfrastructure framework developed in house through NSF funded CDI-Type I: CiiWork for data assimilation, interpretation and open distribution model. In addition to collection and integration of existing information about volcanic products, this project will focus on filling the information gaps about unique physico-chemical characteristics of very fine (\u003c3 micrometer) volcanic particles (cryptotephra) that are present in Antarctic ice cores. This component of research will involve improving analytical methodology for detecting cryptotephra layers in ice, and will train a new generation of scientists to apply an array of modern state?of?the-art instrumentation available to the project team. \u003cbr/\u003e\u003cbr/\u003eThe recognized importance of tephra in establishing a chronological framework for volcanic and sedimentary successions has already resulted in the development of robust regional tephrochronological frameworks (e.g. Europe, Kamchatka, New Zealand, Western North America). The AntT project will provide this framework for Antarctic tephrochronology, as needed for precise correlation records between Antarctic ice cores (e.g. WAIS Divide, RICE, ITASE) and global paleoclimate archives. The results of AntT will be of particular significance to climatologists, paleoclimatologists, atmospheric chemists, geochemists, climate modelers, solar-terrestrial physicists, environmental statisticians, and policy makers for designing solutions to mitigate or cope with likely future impacts of climate change events on modern society.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Hartman, Laura; Wheatley, Sarah D.; Kurbatov, Andrei V.", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Developing an Antarctic Tephra Database for Interdisciplinary Paleoclimate Research (AntT)", "uid": "p0000328", "west": -180.0}, {"awards": "1341390 Frank, Tracy", "bounds_geometry": null, "dataset_titles": "Stable carbon and oxygen isotope data from drill cores from McMurdo Sound, Antarctica", "datasets": [{"dataset_uid": "000195", "doi": "", "keywords": null, "people": null, "repository": "EarthChem", "science_program": null, "title": "Stable carbon and oxygen isotope data from drill cores from McMurdo Sound, Antarctica", "url": "http://dx.doi.org/10.1594/IEDA/100718"}], "date_created": "Fri, 06 Oct 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThis project will use sediment cores from the Victoria Land Basin (VLB), Antarctica, to study secondary (diagenetic) carbonate minerals, as indicators of the basin?s fluid-flow history, within the well-constrained tectonic, depositional, and climatic context provided by sediment cores. This study will provide insights into subsurface processes in Victoria Land Basin, Antarctica and their relationships with the region?s climatic, cryospheric, and tectonic history. The work will utilize cores previously recovered by US-sponsored stratigraphic drilling projects (CIROS, CRP, and ANDRILL projects). This work is motivated by the unexpected discovery of dense brine in the subsurface of Southern McMurdo Sound during drilling by the ANDRILL Southern McMurdo Sound project. The presence of the brine is intriguing because it contradicts previous models for the origin of subsurface fluids that called upon large contributions from glacial melt water. Project objectives involve documenting the distribution of the brine (and potentially other fluids) via characterization of diagenetic precipitates. The approach will involve integration of petrographic and geochemical data (including conventional carbon, oxygen, and ?clumped? isotopes) to fully characterize diagenetic phases and allow development of a robust paragenetic history. This work will provide novel insights into the Cenozoic evolution of the VLB and, more broadly, the role of glacial processes in generating subsurface fluids. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eResults from this project will help understand the origins of brines, groundwater and hydrocarbon reservoirs in analogous modern and ancient deposits elsewhere, which is of broad interest. This project will support the training of one graduate and one undergraduate student at the University of Nebraska-Lincoln (UNL) providing learning opportunities in sedimentary geology and diagenesis, fields with wide applicability. This proposal emphasizes rapid dissemination of results to the scientific community via conference presentations and contributions to peer-reviewed publications. The results will be integrated into education activities designed to develop skills in petrography and diagenesis, which are highly sought after in the energy sector. The project will generate a well-constrained dataset that allows direct linkage of diagenetic phases to environmental and tectonic change across a large sedimentary basin which will provide the basis for a comprehensive case study in an upper-level course (Sedimentary Petrography and Diagenesis) at UNL. In addition, online exercises will be developed and submitted to an open-access site (SEPM Stratigraphy Web) dedicated to sedimentary geology.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Earth Sciences", "paleo_time": null, "persons": "Frank, Tracy; Fielding, Christopher", "platforms": "Not provided", "repo": "EarthChem", "repositories": "EarthChem", "science_programs": null, "south": null, "title": "Insights into the Burial, Tectonic, and Hydrologic History of the Cenozoic Succession in McMurdo Sound, Antarctica through Analysis of Diagenetic Phases", "uid": "p0000256", "west": null}, {"awards": "1142002 Kaplan, Michael", "bounds_geometry": "POLYGON((-58 -63.7,-57.95 -63.7,-57.9 -63.7,-57.85 -63.7,-57.8 -63.7,-57.75 -63.7,-57.7 -63.7,-57.65 -63.7,-57.6 -63.7,-57.55 -63.7,-57.5 -63.7,-57.5 -63.73,-57.5 -63.76,-57.5 -63.79,-57.5 -63.82,-57.5 -63.85,-57.5 -63.88,-57.5 -63.91,-57.5 -63.94,-57.5 -63.97,-57.5 -64,-57.55 -64,-57.6 -64,-57.65 -64,-57.7 -64,-57.75 -64,-57.8 -64,-57.85 -64,-57.9 -64,-57.95 -64,-58 -64,-58 -63.97,-58 -63.94,-58 -63.91,-58 -63.88,-58 -63.85,-58 -63.82,-58 -63.79,-58 -63.76,-58 -63.73,-58 -63.7))", "dataset_titles": "10Be and 14C data from northern Antarctic Peninsula", "datasets": [{"dataset_uid": "601051", "doi": "10.15784/601051", "keywords": "Antarctica; Antarctic Peninsula; Glaciers/ice Sheet; Glaciers/Ice Sheet; GPS; James Ross Island; Sample/collection Description; Sample/Collection Description; Solid Earth", "people": "Kaplan, Michael", "repository": "USAP-DC", "science_program": null, "title": "10Be and 14C data from northern Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601051"}], "date_created": "Tue, 19 Sep 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to investigate last glacial maximum through Holocene glacial change on the northeastern Antarctic Peninsula, an area distinguished by dramatic ice shelf collapses and retreat of upstream glaciers. However, there is a lack of long-term context to know the relative significance of recent events over longer time scales. The PIs will obtain data on former ice margin positions, ice thicknesses, glacier retreat and thinning rates, and Holocene glacier change in the James Ross Island Archipelago and areas near the former Larsen-A ice shelf. These data include maximum- and minimum-limiting 14C and cosmogenic-nuclide exposure dates integrated with geomorphology and stratigraphy. Understanding the extent, nature, and history of glacial events is important for placing current changes in glacial extent into a long-term context. This research will also contribute to understanding the sensitivity of ice shelves and glaciers in this region to climate change. Records of changes in land-terminating glaciers will also address outstanding questions related to climate change since the LGM and through the Holocene. The PIs will collect samples during cooperative field projects with scientists of the Instituto Anta\u0026#769;rtico Argentino and the Korea Polar Research Institute planned as part of existing, larger, research projects.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe proposed work includes collaborations with Argentina and Korea. The PIs are currently involved in or are initiating education and outreach activities that will be incorporated into this project. These include interactions with the American Museum of Natural History, the United States Military Academy at West Point, and undergraduate involvement in their laboratories. This project provides a significant opportunity to engage the public as it focuses on an area where environmental changes are the object of attention in the popular media.", "east": -57.5, "geometry": "POINT(-57.75 -63.85)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; GLACIATION; Not provided", "locations": "Antarctic Peninsula", "north": -63.7, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Kaplan, Michael", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.0, "title": "Terrestrial Geological Context for Glacier Change in the Northeast Antarctica Peninsula", "uid": "p0000337", "west": -58.0}, {"awards": "1142122 Miller, Nathan", "bounds_geometry": "POLYGON((166.163 -76.665,166.2635 -76.665,166.364 -76.665,166.4645 -76.665,166.565 -76.665,166.6655 -76.665,166.766 -76.665,166.8665 -76.665,166.967 -76.665,167.0675 -76.665,167.168 -76.665,167.168 -76.782,167.168 -76.899,167.168 -77.016,167.168 -77.133,167.168 -77.25,167.168 -77.367,167.168 -77.484,167.168 -77.601,167.168 -77.718,167.168 -77.835,167.0675 -77.835,166.967 -77.835,166.8665 -77.835,166.766 -77.835,166.6655 -77.835,166.565 -77.835,166.4645 -77.835,166.364 -77.835,166.2635 -77.835,166.163 -77.835,166.163 -77.718,166.163 -77.601,166.163 -77.484,166.163 -77.367,166.163 -77.25,166.163 -77.133,166.163 -77.016,166.163 -76.899,166.163 -76.782,166.163 -76.665))", "dataset_titles": "Antarctic emerald rockcod have the capacity to compensate for warming when uncoupled from CO2-acidification; Physiological and biochemical measurements on Antarctic dragonfish (Gymnodraco acuticeps) from McMurdo Sound; Physiological and biochemical measurements on juvenile Antarctic rockcod (Trematomus bernacchii) from McMurdo Sound; Thermal windows and metabolic performance curves in a developing Antarctic fish", "datasets": [{"dataset_uid": "601025", "doi": "10.15784/601025", "keywords": "Antarctica; Biota; Fish; McMurdo Sound; Oceans; Ross Sea; Southern Ocean", "people": "Flynn, Erin; Miller, Nathan; Todgham, Anne; Davis, Brittany", "repository": "USAP-DC", "science_program": null, "title": "Physiological and biochemical measurements on juvenile Antarctic rockcod (Trematomus bernacchii) from McMurdo Sound", "url": "https://www.usap-dc.org/view/dataset/601025"}, {"dataset_uid": "601040", "doi": "10.15784/601040", "keywords": "Antarctica; Biota; Fish; McMurdo Sound; Oceans; Ross Sea; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Todgham, Anne; Miller, Nathan", "repository": "USAP-DC", "science_program": null, "title": "Thermal windows and metabolic performance curves in a developing Antarctic fish", "url": "https://www.usap-dc.org/view/dataset/601040"}, {"dataset_uid": "601039", "doi": "10.15784/601039", "keywords": "Antarctica; Biota; Chemistry:fluid; Chemistry:Fluid; CTD Data; Fish; McMurdo Sound; Ocean Acidification; Oceans; Physical Oceanography; Ross Sea; Southern Ocean", "people": "Todgham, Anne; Miller, Nathan", "repository": "USAP-DC", "science_program": null, "title": "Antarctic emerald rockcod have the capacity to compensate for warming when uncoupled from CO2-acidification", "url": "https://www.usap-dc.org/view/dataset/601039"}, {"dataset_uid": "601026", "doi": "10.15784/601026", "keywords": "Antarctica; Biota; Chemistry:fluid; Chemistry:Fluid; CTD Data; Fish; McMurdo Sound; Ocean Acidification; Oceans; Physical Oceanography; Ross Sea; Southern Ocean", "people": "Flynn, Erin; Todgham, Anne; Miller, Nathan; Davis, Brittany", "repository": "USAP-DC", "science_program": null, "title": "Physiological and biochemical measurements on Antarctic dragonfish (Gymnodraco acuticeps) from McMurdo Sound", "url": "https://www.usap-dc.org/view/dataset/601026"}], "date_created": "Tue, 15 Aug 2017 00:00:00 GMT", "description": "Ocean acidification and increased temperatures are projected to be the primary impacts of global climate change on polar marine ecosystems over the next century. While recent research has focused on the effects of these drivers on calcifying organisms, less is known about how these changes may affect vertebrates. This research will focus on two Antarctic fishes, Trematomus bernacchii and Pagothenia borchgrevinki. Fish eggs and larvae will be collected in McMurdo Sound and reared under different temperature and pH regimes. Modern techniques will be used to examine subsequent changes in physiology, growth, development and gene expression over both short and long timescales. The results will fill a missing gap in our knowledge about the response of non-calcifying organisms to projected changes in pH and temperature. Results will be widely disseminated through publications as well as through presentations at national and international meetings; raw data will also be made available through open-access, web-based databases. This project will support the research and training of three graduate and three undergraduate students. As well, this project will foster the development of two modules on climate change and ocean acidification for an Introduction to Biology course.", "east": 167.168, "geometry": "POINT(166.6655 -77.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.665, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Miller, Nathan; Todgham, Anne", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.835, "title": "RUI: Synergistic effects of Ocean Acidification and Warming on Larval Development in Antarctic Fishes", "uid": "p0000411", "west": 166.163}, {"awards": "1245879 Nitsche, Frank O.", "bounds_geometry": null, "dataset_titles": "NBP1503 data collected during field expedition", "datasets": [{"dataset_uid": "200001", "doi": "10.7284/901478", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1503 data collected during field expedition", "url": "https://www.rvdata.us/search/cruise/NBP1503"}], "date_created": "Sun, 30 Jul 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThis project will determine the potential vulnerability of key ice streams to incursions of warmer ocean water onto the continental shelf and if this mechanism could already explain any of the observed thinning of the ice sheet. It will provide important constrains on ice dynamic of the investigated section of the EAIS, and thus will be critical for future ice sheet models and provide mechanisms for EAIS contributions to past sea level high-stand. The PI proposes to investigate four key ice stream systems on the continental shelf between ~90\u00c2\u00b0E and 160\u00c2\u00b0E. They will use multibeam bathymetry to identify if and where cross-shelf troughs exist to help determine whether these troughs could provide potential pathways for warmer ocean water. Furthermore, detailed analysis of morphological features of these troughs could provide information on past ice dynamic, maximum extent, and flow direction of related paleo ice streams. The PIs will also conduct water column measurements along these troughs and on the continental slope to determine whether warmer ocean water could enter the shelf in the near future, or if such water has already entered any troughs, and thus might be causing the observed thinning of some ice streams.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis project includes the participation and support of undergraduate and graduate students in field work and data analysis. The possible involvement of a PolarTREC teacher and the Earth2Class teachers program will reach out to K-12 students.", "east": 134.6, "geometry": "POINT(125.05 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "WATER TEMPERATURE; Polar; SALINITY; Antarctica; Southern Ocean; R/V NBP; BATHYMETRY", "locations": "Polar; Antarctica; Southern Ocean", "north": -63.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Nitsche, Frank O.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -66.0, "title": "Vulnerability of East Antarctic Ice Streams to warm Ocean Water Incursions", "uid": "p0000394", "west": 115.5}, {"awards": "1142129 Lamanna, Matthew", "bounds_geometry": "POLYGON((-60 -63.5,-59.6 -63.5,-59.2 -63.5,-58.8 -63.5,-58.4 -63.5,-58 -63.5,-57.6 -63.5,-57.2 -63.5,-56.8 -63.5,-56.4 -63.5,-56 -63.5,-56 -63.7,-56 -63.9,-56 -64.1,-56 -64.3,-56 -64.5,-56 -64.7,-56 -64.9,-56 -65.1,-56 -65.3,-56 -65.5,-56.4 -65.5,-56.8 -65.5,-57.2 -65.5,-57.6 -65.5,-58 -65.5,-58.4 -65.5,-58.8 -65.5,-59.2 -65.5,-59.6 -65.5,-60 -65.5,-60 -65.3,-60 -65.1,-60 -64.9,-60 -64.7,-60 -64.5,-60 -64.3,-60 -64.1,-60 -63.9,-60 -63.7,-60 -63.5))", "dataset_titles": "2008-2016 AMNH accessioned vertebrate fossils from Seymour Island; 3D digital reconstructions of vocal organs of Antarctic Cretaceous bird Vegavis and Paleogene bird Presbyornis", "datasets": [{"dataset_uid": "601035", "doi": "10.15784/601035", "keywords": "Antarctica; Biota; Birds", "people": "Salisbury, Steven; Lamanna, Matthew; Clarke, Julia", "repository": "USAP-DC", "science_program": null, "title": "3D digital reconstructions of vocal organs of Antarctic Cretaceous bird Vegavis and Paleogene bird Presbyornis", "url": "https://www.usap-dc.org/view/dataset/601035"}, {"dataset_uid": "601112", "doi": "10.15784/601112", "keywords": "Antarctica; Biota; Penguin; Seymour Island; Vertebrates", "people": "MacPhee, Ross", "repository": "USAP-DC", "science_program": null, "title": "2008-2016 AMNH accessioned vertebrate fossils from Seymour Island", "url": "https://www.usap-dc.org/view/dataset/601112"}], "date_created": "Wed, 12 Jul 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe role that Antarctica has played in vertebrate evolution and paleobiogeography during the Late Cretaceous and early Paleogene is largely unknown. Evidence indicates that Antarctica was home to a diverse flora during the Late Cretaceous and Paleogene, yet the vertebrates that must have existed on the continent remain virtually unknown. To fill this gap, the PIs have formed the Antarctic Vertebrate Paleontology Initiative (AVPI), whose goal is to search for and collect Late Cretaceous-Paleogene vertebrate fossils in Antarctica at localities that have never been properly surveyed, as well as in areas of proven potential. Two field seasons are proposed for the James Ross Island Group on the northeastern margin of the Antarctic Peninsula. Expected finds include chondrichthyan and osteichthyan fishes, marine reptiles, ornithischian and non-avian theropod dinosaurs, ornithurine birds, and therian and non-therian mammals. Hypotheses to be tested include: 1) multiple extant bird and/or therian mammal lineages originated during the Cretaceous and survived the K-Pg boundary extinction event; 2) the \"Scotia Portal\" permitted the dispersal of continental vertebrates between Antarctica and South America prior to the latest Cretaceous and through to the late Paleocene or early Eocene; 3) Late Cretaceous non-avian dinosaurs from Antarctica are closely related to coeval taxa from other Gondwanan landmasses; 4) terminal Cretaceous marine reptile faunas from southern Gondwana differed from contemporaneous but more northerly assemblages; and 5) the collapse of Antarctic ichthyofaunal diversity during the K-Pg transition was triggered by a catastrophic extinction.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe PIs will communicate discoveries to audiences through a variety of channels, such as the Dinosaurs in Their Time exhibition at Carnegie Museum of Natural History and the outreach programs of the Environmental Science Institute of the University of Texas at Austin. In addition, Carnegie Museum will launch a student-oriented programming initiative using AVPI research as a primary focus. This array of activities will help some 2,000 Pittsburgh-area undergraduates to explore the relevance of deep-time discoveries to critical modern issues. The AVPI will provide research opportunities for eight undergraduate and three graduate students, several of whom will receive field training in Antarctica. Fossils will be accessioned into the Carnegie Museum collection, and made accessible virtually through the NSF-funded Digital Morphology library at University of Texas.", "east": -56.0, "geometry": "POINT(-58 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; Not provided", "locations": null, "north": -63.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Lamanna, Matthew", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.5, "title": "Collaborative Research: Late Cretaceous-Paleogene Vertebrates from Antarctica: Implications for Paleobiogeography, Paleoenvironment, and Extinction in Polar Gondwana", "uid": "p0000380", "west": -60.0}, {"awards": "1148982 Hansen, Samantha", "bounds_geometry": "POLYGON((153.327 -73.032547,154.5063012 -73.032547,155.6856024 -73.032547,156.8649036 -73.032547,158.0442048 -73.032547,159.223506 -73.032547,160.4028072 -73.032547,161.5821084 -73.032547,162.7614096 -73.032547,163.9407108 -73.032547,165.120012 -73.032547,165.120012 -73.3530275,165.120012 -73.673508,165.120012 -73.9939885,165.120012 -74.314469,165.120012 -74.6349495,165.120012 -74.95543,165.120012 -75.2759105,165.120012 -75.596391,165.120012 -75.9168715,165.120012 -76.237352,163.9407108 -76.237352,162.7614096 -76.237352,161.5821084 -76.237352,160.4028072 -76.237352,159.223506 -76.237352,158.0442048 -76.237352,156.8649036 -76.237352,155.6856024 -76.237352,154.5063012 -76.237352,153.327 -76.237352,153.327 -75.9168715,153.327 -75.596391,153.327 -75.2759105,153.327 -74.95543,153.327 -74.6349495,153.327 -74.314469,153.327 -73.9939885,153.327 -73.673508,153.327 -73.3530275,153.327 -73.032547))", "dataset_titles": "Crustal Structure beneath the Northern Transantarctic Mountains and Wilkes Subglacial Basin: Implications for Tectonic Origins; Shear Wave Splitting Analysis and Seismic Anisotropy beneath the Northern Transantarctic Mountains; Upper Mantle Seismic Structure beneath the Northern Transantarctic Mountains from Regional P- and S-wave Tomography; Upper Mantle Shear Wave Velocity Structure beneath the Northern Transantarctic Mountains", "datasets": [{"dataset_uid": "601019", "doi": "10.15784/601019", "keywords": "Antarctica; Geology/Geophysics - Other; GPS; Sample/collection Description; Sample/Collection Description; Seismology; Shearwave Spitting; Solid Earth; Transantarctic Mountains", "people": "Hansen, Samantha", "repository": "USAP-DC", "science_program": null, "title": "Shear Wave Splitting Analysis and Seismic Anisotropy beneath the Northern Transantarctic Mountains", "url": "https://www.usap-dc.org/view/dataset/601019"}, {"dataset_uid": "601018", "doi": "10.15784/601018", "keywords": "Antarctica; Geology/Geophysics - Other; Model; Seismology; Solid Earth; Tomography; Transantarctic Mountains", "people": "Hansen, Samantha", "repository": "USAP-DC", "science_program": null, "title": "Upper Mantle Shear Wave Velocity Structure beneath the Northern Transantarctic Mountains", "url": "https://www.usap-dc.org/view/dataset/601018"}, {"dataset_uid": "601017", "doi": "10.15784/601017", "keywords": "Antarctica; Geology/Geophysics - Other; Model; Seismology; Solid Earth; Tomography; Transantarctic Mountains", "people": "Hansen, Samantha", "repository": "USAP-DC", "science_program": null, "title": "Upper Mantle Seismic Structure beneath the Northern Transantarctic Mountains from Regional P- and S-wave Tomography", "url": "https://www.usap-dc.org/view/dataset/601017"}, {"dataset_uid": "601194", "doi": "10.15784/601194", "keywords": "Antarctica; Transantarctic Mountains", "people": "Hansen, Samantha", "repository": "USAP-DC", "science_program": null, "title": "Crustal Structure beneath the Northern Transantarctic Mountains and Wilkes Subglacial Basin: Implications for Tectonic Origins", "url": "https://www.usap-dc.org/view/dataset/601194"}], "date_created": "Sun, 04 Jun 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eTo understand Antarctica\u0027s geodynamic development, origin of the Transantarctic Mountains (TAMs) and the Wilkes Subglacial Basin (WSB) must be determined. Current constraints on the crustal thickness and seismic velocity structure beneath the TAMs and the WSB are limited, leading to uncertainties over competing geologic models that have been suggested to explain their formation. The PI proposes to broaden the investigation of this region with a new seismic deployment, the Transantarctic Mountains Northern Network (TAMNNET), a 15-station array across the northern TAMs and the WSB that will fill a major gap in seismic coverage. Data from TAMNNET will be combined with that from other previous and ongoing seismic initiatives and will be analyzed using proven modeling techniques to generate a detailed image of the seismic structure beneath the TAMs and the WSB. These data will be used to test three fundamental hypotheses: the TAMs are underlain by thickened crust, the WSB is characterized by thin crust and thick sedimentary layers, and slow seismic velocities are prevalent along strike beneath the TAMs. Results from the proposed study will provide new information about the nature and formation of the Antarctic continent and will help to advance our understanding of important global processes, such as mountain building and basin formation. The proposed research also has important implications for other fields of Antarctic science. Constraints on the origin of the TAMs uplift are critical for climate and ice sheet models, and new information acquired about variations in the thermal and lithospheric structure beneath the TAMs and the WSB will be used to estimate critical ice sheet boundary conditions. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis project incorporates three educational strategies to promote the integration of teaching and research. Graduate students will be trained in Antarctic tectonics and seismic processing through hands-on fieldwork and data analysis techniques. Through NSF\u0027s PolarTREC program, the PI will work with K-12 educators. The PI will develop a three-week summer field program for recent high school graduates and early-career undergraduate students from Minority-Serving Institutions in Alabama. Teaching materials and participant experiences will be shared with individuals outside the program via a course website. Following the summer program, participants who were particularly engaged will be offered internship opportunities to analyze TAMNNET data. In successive years, the students could assist with fieldwork and could be recruited into the graduate program under the PI\u0027s supervision. Ultimately, this program would not only serve to educate undergraduates but would also generate a pipeline of underrepresented students into the geosciences.", "east": 165.120012, "geometry": "POINT(159.223506 -74.6349495)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": -73.032547, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Hansen, Samantha", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.237352, "title": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin", "uid": "p0000300", "west": 153.327}, {"awards": "1443554 Buys, Emmanuel", "bounds_geometry": "POLYGON((166.163 -76.665,166.2635 -76.665,166.364 -76.665,166.4645 -76.665,166.565 -76.665,166.6655 -76.665,166.766 -76.665,166.8665 -76.665,166.967 -76.665,167.0675 -76.665,167.168 -76.665,167.168 -76.782,167.168 -76.899,167.168 -77.016,167.168 -77.133,167.168 -77.25,167.168 -77.367,167.168 -77.484,167.168 -77.601,167.168 -77.718,167.168 -77.835,167.0675 -77.835,166.967 -77.835,166.8665 -77.835,166.766 -77.835,166.6655 -77.835,166.565 -77.835,166.4645 -77.835,166.364 -77.835,166.2635 -77.835,166.163 -77.835,166.163 -77.718,166.163 -77.601,166.163 -77.484,166.163 -77.367,166.163 -77.25,166.163 -77.133,166.163 -77.016,166.163 -76.899,166.163 -76.782,166.163 -76.665))", "dataset_titles": "Biosamples and observations from Weddell Seal colonies in McMurdo Sound during the 2015-2016 Antarctic field season", "datasets": [{"dataset_uid": "601028", "doi": "10.15784/601028", "keywords": "Antarctica; Biota; McMurdo Sound; Ross Sea; Sample/collection Description; Sample/Collection Description; Seals", "people": "Buys, Emmanuel; Hindle, Allyson", "repository": "USAP-DC", "science_program": null, "title": "Biosamples and observations from Weddell Seal colonies in McMurdo Sound during the 2015-2016 Antarctic field season", "url": "https://www.usap-dc.org/view/dataset/601028"}], "date_created": "Fri, 26 May 2017 00:00:00 GMT", "description": "The Weddell seal is a champion diving mammal. The physiology that permits these animals to sustain extended breath-hold periods and survive the extreme pressure of diving deep allows them to thrive in icy Antarctic waters. Key elements of their physiological specializations to breath-hold diving are their ability for remarkable adjustment of their heart and blood vessel system, coordinating blood pressure and flow to specific body regions based on their metabolic requirements, and their ability to sustain periods without oxygen. Identifying the details of these strategies has tremendous potential to better inform human medicine, helping us to develop novel therapies for cardiovascular trauma (e.g. stroke, heart attack) and diseases associated with blunted oxygen delivery to tissues (e.g. pneumonia, sepsis, or cancer). The goal of this project is to document specific genes that control these cardiovascular adjustments in seals, and to compare their abundance and activity with humans. Specifically, the investigators will study a signaling pathway that coordinates local blood flow. They will also use tissue samples to generate cultured cells from Weddell seals that can be used to study the molecular effects of low oxygen conditions in the laboratory. The project will further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. The project will train a pre-veterinary student researcher will conduct public outreach via a center for community health improvement, a multicultural affairs office, and a public aquarium. The goal of this study is to unravel the molecular mechanisms underlying the dive response. A hallmark of the dive response is tissue-specific vascular system regulation, likely resulting from variation in both nerve inputs and in production of local signaling molecules produced by blood vessel cells. The investigators will use emerging genomic information to begin to unravel the genetics underlying redistribution of the circulation during diving. They will also directly test the hypothesis that modifications in the signaling system prevent local blood vessel changes under low oxygen conditions, thereby allowing the centrally mediated diving reflex to override local physiological responses and to control the constriction of blood vessel walls in Weddell seals. They will perform RNA-sequencing of Weddell seal tissues and use the resulting sequence, along with information from other mammals such as dog, to obtain a full annotation (identifying all genes based on named features of reference genomes) of the existing genome assembly for the Weddell seal, facilitating comparative and species-specific genomic research. They will also generate a Weddell seal pluripotent stem cell line which should be a valuable research tool for cell biologists, molecular biologists and physiologists that will allow them to further test their hypotheses. It is expected that the proposed studies will advance our knowledge of the biochemical and physiological adaptations that allow the Weddell seal to thrive in the Antarctic environment.", "east": 167.168, "geometry": "POINT(166.6655 -77.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.665, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Buys, Emmanuel; Costa, Daniel; Zapol, Warren; Hindle, Allyson", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.835, "title": "Unraveling the Genomic and Molecular Basis of the Dive Response: Nitric Oxide Signaling and Vasoregulation in the Weddell Seal", "uid": "p0000072", "west": 166.163}, {"awards": "1246463 Burns, Jennifer", "bounds_geometry": "POINT(149 -80)", "dataset_titles": "1970s - 1980s Kooyman-Billups TDR Dive Records from Weddell Seals in McMurdo Sound; Cortisol levels in Weddell seal fur; Seasonal Dive Data ; Specimen logs and observations from Weddell Seal colonies in Erebus Bay, 2013-2017; Weddell Seal Heat Flux Dataset; Weddell seal iron dynamics and oxygen stores across lactation; Weddell seal metabolic hormone data; Weddell Seal Molt Phenology Dataset; Weddell Seal Molt Survey Data; Weddell seal summer diving behavior", "datasets": [{"dataset_uid": "601560", "doi": "10.15784/601560", "keywords": "Antarctica; Biota; Diving Behavior; McMurdo Sound; Weddell Seal", "people": "Tsai, EmmaLi", "repository": "USAP-DC", "science_program": null, "title": "1970s - 1980s Kooyman-Billups TDR Dive Records from Weddell Seals in McMurdo Sound", "url": "https://www.usap-dc.org/view/dataset/601560"}, {"dataset_uid": "601137", "doi": "10.15784/601137", "keywords": "Antarctica; Biota; Ross Sea; Seals; Southern Ocean; Weddell Seal", "people": "Beltran, Roxanne; Burns, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Weddell seal summer diving behavior", "url": "https://www.usap-dc.org/view/dataset/601137"}, {"dataset_uid": "601134", "doi": "10.15784/601134", "keywords": "Antarctica; Biota; Cortisol; Fur; Ross Sea; Seals; Southern Ocean; Visual Observations; Weddell Seal", "people": "Burns, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Cortisol levels in Weddell seal fur", "url": "https://www.usap-dc.org/view/dataset/601134"}, {"dataset_uid": "601133", "doi": "10.15784/601133", "keywords": "Antarctica; Biota; Ross Sea; Seals; Visual Observations; Weddell Seal", "people": "Burns, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Weddell Seal Molt Survey Data", "url": "https://www.usap-dc.org/view/dataset/601133"}, {"dataset_uid": "601131", "doi": "10.15784/601131", "keywords": "Antarctica; B-292-M; Biota; Ross Sea; Seals; Southern Ocean; Weddell Seal", "people": "Burns, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Weddell Seal Molt Phenology Dataset", "url": "https://www.usap-dc.org/view/dataset/601131"}, {"dataset_uid": "601271", "doi": "10.15784/601271", "keywords": "Antarctica; Heat Flux; Infrared Thermography; Physiological Conditions; Surface Temperatures; Thermoregulation; Weddell Seal", "people": "Walcott, Skyla", "repository": "USAP-DC", "science_program": null, "title": "Weddell Seal Heat Flux Dataset", "url": "https://www.usap-dc.org/view/dataset/601271"}, {"dataset_uid": "601027", "doi": "10.15784/601027", "keywords": "Antarctica; Biota; McMurdo Sound; Oceans; Ross Sea; Sample/collection Description; Sample/Collection Description; Seals", "people": "Burns, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Specimen logs and observations from Weddell Seal colonies in Erebus Bay, 2013-2017", "url": "https://www.usap-dc.org/view/dataset/601027"}, {"dataset_uid": "601338", "doi": "10.15784/601338", "keywords": "Animal Behavior Observation; Antarctica; Biota; McMurdo Sound; Ross Sea; Seal Dive Data; Weddell Seal", "people": "Burns, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Seasonal Dive Data ", "url": "https://www.usap-dc.org/view/dataset/601338"}, {"dataset_uid": "601840", "doi": null, "keywords": "Antarctica; Cryosphere; Hormones; McMurdo Sound; Ross Sea; Weddell Seal", "people": "Kirkham, Amy", "repository": "USAP-DC", "science_program": null, "title": "Weddell seal metabolic hormone data", "url": "https://www.usap-dc.org/view/dataset/601840"}, {"dataset_uid": "601587", "doi": "10.15784/601587", "keywords": "Aerobic; Antarctica; Dive Capacity; Iron; McMurdo Sound; Weddell Seal", "people": "Shero, Michelle", "repository": "USAP-DC", "science_program": null, "title": "Weddell seal iron dynamics and oxygen stores across lactation", "url": "https://www.usap-dc.org/view/dataset/601587"}], "date_created": "Wed, 24 May 2017 00:00:00 GMT", "description": "Marine mammals that inhabit high latitude environments have evolved unique mechanisms to execute a suite of energetically-costly life history events (CLHEs) within a relatively short timeframe when conditions are most favorable. Understanding the intrinsic and extrinsic factors that regulate CLHEs is particularly important in species such as Weddell seals, as both reproduction and molt are associated with large reductions in foraging effort, and the timing and outcome of each appears linked with the other. The long-term mark recapture program on Erebus Bay\u0027s Weddell seals provides a unique opportunity to examine CLHEs in a known-history population. The proposed work will monitor physiological condition, pregnancy status, and behavior at various times throughout the year to determine if molt timing is influenced by prior reproductive outcome, and if it, in turn, influences future reproductive success. These data will then be used to address the demographic consequences of trade-offs between CLHEs in Weddell seals. The impact of environmental conditions and CLHE timing on population health will also be modeled so that results can be extended to other climates and species. \u003cbr/\u003e\u003cbr/\u003eAn improved understanding of the interactions between CLHEs and the environment is important in predicting the response of organisms from higher trophic levels to climate change. Results will be widely disseminated through publications as well as through presentations at national and international meetings. In addition, raw data will be made available through open-access databases. This project will support the research and training of graduate students and a post-doctoral researcher and will further foster an extensive public outreach collaboration.", "east": 165.0, "geometry": "POINT(165 -77)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; USAP-DC; Seal Dive Data; Weddell Seal", "locations": null, "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Burns, Jennifer", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.0, "title": "The Cost of A New Fur Coat: Interactions between Molt and Reproduction in Weddell Seals", "uid": "p0000229", "west": 165.0}, {"awards": "1245580 Castro, M. Clara", "bounds_geometry": "POINT(162.167 -77.733)", "dataset_titles": "Developing a New Paleoclimate Proxy for Polar and Alpine Glacial Regions Based on Noble Gases", "datasets": [{"dataset_uid": "600389", "doi": "10.15784/600389", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Critical Zone; Geochemistry; Noble Gas; Paleoclimate; Ross Ice Shelf; Ross Sea; Taylor Valley", "people": "Castro, M. Clara", "repository": "USAP-DC", "science_program": null, "title": "Developing a New Paleoclimate Proxy for Polar and Alpine Glacial Regions Based on Noble Gases", "url": "https://www.usap-dc.org/view/dataset/600389"}], "date_created": "Mon, 30 Jan 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eNoble gases in groundwater systems can indicate past climates in ice-free regions through estimation of noble gas temperatures. Traditional noble gas temperatures cannot be derived in ice-covered regions where water is not in contact with the atmosphere. The goal of the proposed work is to take advantage of noble gas properties in ice covered lakes at the ice/water interface to develop a new paleoclimate proxy with the potential to be routinely used in both polar and alpine glacial regions. The evolution of the Taylor Valley lakes is intimately connected to the dynamics of nearby glaciers, as well as the advance and retreat of the Ross Ice Shelf, both of which are dictated by climate change. The perennial ice cover of the lakes form at the water/ice interface and sublimate at the top rendering these lakes ideal to test and develop this new proxy. The proposed research involves conducting an extensive noble gas sampling campaign of lake water, stream water, ice covers and glacial ice. This data set, together with data continuously collected in the area will provide a solid basis to develop, test and refine mathematical models capable of accurately describing heavy noble gas concentration profiles as well as their overall inventory in the lakes over time. These will provide information on the occurrence of major climatic events while simultaneously providing temporal constraints on such events. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe findings of this work will be inserted into a new class that the PI has created at the University of Michigan targeted at non-science majors. It will create research opportunities for 1-2 undergraduates each year and will support a PhD student. The outcomes of this research could have strong societal relevance.", "east": 162.167, "geometry": "POINT(162.167 -77.733)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.733, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Castro, M. Clara; Doran, Peter; Kenig, Fabien", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.733, "title": "Developing a New Paleoclimate Proxy for Polar and Alpine Glacial Regions Based on Noble Gases", "uid": "p0000388", "west": 162.167}, {"awards": "1043554 Willenbring, Jane", "bounds_geometry": "POINT(161.5 -77.5)", "dataset_titles": "Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins", "datasets": [{"dataset_uid": "600379", "doi": "10.15784/600379", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Cosmogenic Radionuclides; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Isotope; Sample/collection Description; Sample/Collection Description; Transantarctic Mountains", "people": "Willenbring, Jane", "repository": "USAP-DC", "science_program": null, "title": "Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins", "url": "https://www.usap-dc.org/view/dataset/600379"}], "date_created": "Wed, 09 Nov 2016 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to address the question of whether ice surface melting zones developed at high elevations during warm climatic phases in the Transantarctic Mountains. Evidence from sediment cores drilled by the ANDRILL program indicates that open water in the Ross Sea could have been a source of warmth during Pliocene and Pleistocene. The question is whether marine warmth penetrated inland to the ice sheet margins. The glacial record may be ill suited to answer this question, as cold-based glaciers may respond too slowly to register brief warmth. Questions also surround possible orbital controls on regional climate and ice sheet margins. Northern Hemisphere insolation at obliquity and precession timescales is thought to control Antarctic climate through oceanic or atmospheric connections, but new thinking suggests that the duration of Southern Hemisphere summer may be more important. The PIs propose to use high elevation alluvial deposits in the Transantarctic Mountains as a proxy for inland warmth. These relatively young fans, channels, and debris flow levees stand out as visible evidence for the presence of melt water in an otherwise ancient, frozen landscape. Based on initial analyses of an alluvial fan in the Olympus Range, these deposits are sensitive recorders of rare melt events that occur at orbital timescales. For their study they will 1) map alluvial deposits using aerial photography, satellite imagery and GPS assisted field surveys to establish water sources and to quantify parameters effecting melt water production, 2) date stratigraphic sequences within these deposits using OSL, cosmogenic nuclide, and interbedded volcanic ash chronologies, 3) use paired nuclide analyses to estimate exposure and burial times, and rates of deposition and erosion, and 4) use micro and regional scale climate modeling to estimate paleoenvironmental conditions associated with melt events.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis study will produce a record of inland melting from sites adjacent to ice sheet margins to help determine controls on regional climate along margins of the East Antarctic Ice Sheet to aid ice sheet and sea level modeling studies. The proposal will support several graduate and undergraduates. A PhD student will be supported on existing funding. The PIs will work with multiple K 12 schools to conduct interviews and webcasts from Antarctica and they will make follow up visits to classrooms after the field season is complete.", "east": 161.5, "geometry": "POINT(161.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Willenbring, Jane", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.5, "title": "Collaborative Research: Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins", "uid": "p0000429", "west": 161.5}, {"awards": "1043485 Curtice, Josh; 1043018 Pollard, David; 1043517 Clark, Peter", "bounds_geometry": "POLYGON((163.5 -77.57,163.685 -77.57,163.87 -77.57,164.055 -77.57,164.24 -77.57,164.425 -77.57,164.61 -77.57,164.795 -77.57,164.98 -77.57,165.165 -77.57,165.35 -77.57,165.35 -77.645,165.35 -77.72,165.35 -77.795,165.35 -77.87,165.35 -77.945,165.35 -78.02,165.35 -78.095,165.35 -78.17,165.35 -78.245,165.35 -78.32,165.165 -78.32,164.98 -78.32,164.795 -78.32,164.61 -78.32,164.425 -78.32,164.24 -78.32,164.055 -78.32,163.87 -78.32,163.685 -78.32,163.5 -78.32,163.5 -78.245,163.5 -78.17,163.5 -78.095,163.5 -78.02,163.5 -77.945,163.5 -77.87,163.5 -77.795,163.5 -77.72,163.5 -77.645,163.5 -77.57))", "dataset_titles": "A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea; Ice Sheet Model Output, West Antarctic Ice Sheet Deglaciation", "datasets": [{"dataset_uid": "609639", "doi": "10.7265/N5NC5Z53", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model", "people": "Pollard, David", "repository": "USAP-DC", "science_program": null, "title": "Ice Sheet Model Output, West Antarctic Ice Sheet Deglaciation", "url": "https://www.usap-dc.org/view/dataset/609639"}, {"dataset_uid": "600123", "doi": "10.15784/600123", "keywords": "Antarctica; Cosmogenic Dating; Ross Sea; Sample/collection Description; Sample/Collection Description; Southern Ocean; WAIS", "people": "Curtice, Josh; Kurz, Mark D.", "repository": "USAP-DC", "science_program": null, "title": "A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600123"}], "date_created": "Sat, 15 Oct 2016 00:00:00 GMT", "description": "1043517/Clark\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop a better understanding of the response of the WAIS to climate change. The timing of the last deglaciation of the western Ross Sea will be improved using in situ terrestrial cosmogenic nuclides (3He, 10Be, 14C, 26Al, 36Cl) to date glacial erratics at key areas and elevations along the western Ross Sea coast. A state-of-the art ice sheet-shelf model will be used to identify mechanisms of deglaciation of the Ross Sea sector of WAIS. The model results and forcing will be compared with observations including the new cosmogenic data proposed here, with the aim of better determining and understanding the history and causes of WAIS deglaciation in the Ross Sea. There is considerable uncertainty, however, in the history of grounding line retreat from its last glacial maximum position, and virtually nothing is known about the timing of ice- surface lowering prior to ~10,000 years ago. Given these uncertainties, we are currently unable to assess one of the most important questions regarding the last deglaciation of the global ice sheets, namely as to whether the Ross Sea sector of WAIS contributed significantly to meltwater pulse 1A (MWP-1A), an extraordinarily rapid (~500-year duration) episode of ~20 m sea-level rise that occurred ~14,500 years ago. The intellectual merit of this project is that recent observations of startling changes at the margins of the Greenland and Antarctic ice sheets indicate that dynamic responses to warming may play a much greater role in the future mass balance of ice sheets than considered in current numerical projections of sea level rise. The broader impacts of this work are that it has direct societal relevance to developing an improved understanding of the response of the West Antarctic ice sheet to current and possible future environmental changes including the sea-level response to glacier and ice sheet melting due to global warming. The PI will communicate results from this project to a variety of audiences through the publication of peer-reviewed papers and by giving talks to public audiences. Finally the project will support a graduate student and undergraduate students in all phases of field-work, laboratory work and data interpretation.", "east": 165.35, "geometry": "POINT(164.425 -77.945)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e DATA ANALYSIS \u003e ENVIRONMENTAL MODELING \u003e COMPUTER", "is_usap_dc": true, "keywords": "Ocean Depth; Not provided; Bed Elevation; Model Output; Sea Level Rise; Surface Accumulation Rate; Surface Melt Rate; Ocean Melt Rate; Total Ice Volume; Modeling; Calving Rate; Total Ice Area; LABORATORY", "locations": null, "north": -77.57, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Pollard, David; Curtice, Josh; Clark, Peter; Kurz, Mark D.", "platforms": "Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.32, "title": "Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "uid": "p0000194", "west": 163.5}, {"awards": "1246202 Hofmann, Gretchen", "bounds_geometry": "POLYGON((163.317388 -77.3354,163.6520742 -77.3354,163.9867604 -77.3354,164.3214466 -77.3354,164.6561328 -77.3354,164.990819 -77.3354,165.3255052 -77.3354,165.6601914 -77.3354,165.9948776 -77.3354,166.3295638 -77.3354,166.66425 -77.3354,166.66425 -77.386975,166.66425 -77.43855,166.66425 -77.490125,166.66425 -77.5417,166.66425 -77.593275,166.66425 -77.64485,166.66425 -77.696425,166.66425 -77.748,166.66425 -77.799575,166.66425 -77.85115,166.3295638 -77.85115,165.9948776 -77.85115,165.6601914 -77.85115,165.3255052 -77.85115,164.990819 -77.85115,164.6561328 -77.85115,164.3214466 -77.85115,163.9867604 -77.85115,163.6520742 -77.85115,163.317388 -77.85115,163.317388 -77.799575,163.317388 -77.748,163.317388 -77.696425,163.317388 -77.64485,163.317388 -77.593275,163.317388 -77.5417,163.317388 -77.490125,163.317388 -77.43855,163.317388 -77.386975,163.317388 -77.3354))", "dataset_titles": "mRNA sequencing - RNAseq; Nearshore pH, temperature, (salinity, depth) at mooring sites in McMurdo Sound, Antarctica, Overwinter 2011-2016; pH temp sal measurement data", "datasets": [{"dataset_uid": "002576", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "pH temp sal measurement data", "url": "https://www.bco-dmo.org/dataset/639502"}, {"dataset_uid": "000181", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "mRNA sequencing - RNAseq", "url": "http://www.bco-dmo.org/dataset/639502"}, {"dataset_uid": "601141", "doi": "10.15784/601141", "keywords": "Antarctica; McMurdo Sound; Mcmurdo Station; Mooring; Oceans; Ocean Temperature; PH; Physical Oceanography; Ross Sea; Sea Surface Temperature; Seawater Measurements; Southern Ocean; Temperature", "people": "Kapsenberg, Lydia; Hofmann, Gretchen; Hoshijima, Umihiko", "repository": "USAP-DC", "science_program": null, "title": "Nearshore pH, temperature, (salinity, depth) at mooring sites in McMurdo Sound, Antarctica, Overwinter 2011-2016", "url": "https://www.usap-dc.org/view/dataset/601141"}], "date_created": "Tue, 13 Sep 2016 00:00:00 GMT", "description": "The research supported in this project will examine the effects of environmental change on a key Antarctic marine invertebrate, a pelagic mollusk, the pteropod, Limacina helicina antarctica. There are two main activities in this project: (1) to deploy oceanographic equipment ? in this case, autonomously recording pH sensors called SeaFETs and other devices that record temperature and salinity, and (2) to use these environmental data in the laboratory at McMurdo Station to study the response of the marine invertebrates to future changes in water quality that is expected in the next few decades. Notably, changes in oceanic pH (aka ocean acidification) and ocean warming are projected to be particularly threatening to calcifying marine organisms in cold-water, high latitude seas, making tolerance data on these organisms a critical research need in Antarctic marine ecosystems. \u003cbr/\u003e\u003cbr/\u003eThese Antarctic shelled-animals are especially vulnerable to dissolution stress from ocean acidification because they currently inhabit seawater that is barely at the saturation level to support biogenic calcification. Indeed, these polar animals are considered to be the \u0027first responders\u0027 to chemical changes in the surface oceans. Thus, this project will lead to information about the adaptive capacity of L. helcina antarctica. From an ecological perspective this is important because this animal is a critical part of the Antarctic food chain in coastal waters and changes in its abundance will impact other species. Finally, the research conducted in this project will serve as a training and educational opportunity for undergraduate and graduate students as well as postdoctoral scholars.", "east": 166.66425, "geometry": "POINT(164.990819 -77.593275)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.3354, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hofmann, Gretchen", "platforms": "Not provided", "repo": "BCO-DMO", "repositories": "BCO-DMO; USAP-DC", "science_programs": null, "south": -77.85115, "title": "Ocean Acidification Seascape: Linking Natural Variability and Anthropogenic changes in pH and Temperature to Performance in Calcifying Antarctic Marine Invertebrates", "uid": "p0000390", "west": 163.317388}, {"awards": "0838817 Kyle, Philip", "bounds_geometry": "POLYGON((167 -77.3,167.05 -77.3,167.1 -77.3,167.15 -77.3,167.2 -77.3,167.25 -77.3,167.3 -77.3,167.35 -77.3,167.4 -77.3,167.45 -77.3,167.5 -77.3,167.5 -77.34,167.5 -77.38,167.5 -77.42,167.5 -77.46,167.5 -77.5,167.5 -77.54,167.5 -77.58,167.5 -77.62,167.5 -77.66,167.5 -77.7,167.45 -77.7,167.4 -77.7,167.35 -77.7,167.3 -77.7,167.25 -77.7,167.2 -77.7,167.15 -77.7,167.1 -77.7,167.05 -77.7,167 -77.7,167 -77.66,167 -77.62,167 -77.58,167 -77.54,167 -77.5,167 -77.46,167 -77.42,167 -77.38,167 -77.34,167 -77.3))", "dataset_titles": "Mount Erebus Volcano Observatory III (MEVO III): Conduit Processes and Surveillance", "datasets": [{"dataset_uid": "600153", "doi": "10.15784/600153", "keywords": "Antarctica; Cable Observatory; Intracontinental Magmatism; IntraContinental Magmatism; MEVO; Mount Erebus; Photo/video; Photo/Video; Ross Sea; Solid Earth; Volcano", "people": "Kyle, Philip", "repository": "USAP-DC", "science_program": "MEVO", "title": "Mount Erebus Volcano Observatory III (MEVO III): Conduit Processes and Surveillance", "url": "https://www.usap-dc.org/view/dataset/600153"}], "date_created": "Thu, 23 Jun 2016 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Mount Erebus is Antarctica?s most active volcano that has been in a persistent state of activity for at least the last 35 years. It has a unique geochemistry among the Earth\u0027s active volcanoes and is also unique in hosting a persistent convecting lake(s) of anorthclase phonolite magma in its summit crater. The relative simplicity of the magmatic system, consistency of activity, and accessibility of close-range observation make Erebus attractive as a target for extensive studies. Although the Erebus\u0027 seismicity and eruptive activity and processes are becoming increasingly well understood over years of research, there is a near total lack of understanding its deeper magmatic system. The primary goal of this proposal is to continue supporting the Mt. Erebus Volcano Observatory (MEVO III) improving our current understanding of the Erebus eruptive and non-eruptive magmatic system using an integrated approach from geophysical, geochemical and remote sensing observations. This goal can be grouped into the following fundamental research objectives: (a) to sustain year-round surveillance of on-going volcanic activity primarily using geophysical observatories; (b) to understand processes within the convecting conduit which feeds the persistent lava lakes; and (c) to understand the impact of Erebus eruptive activity upon the Antarctic environment. Continued reliance on students provides a broader impact to this proposed research and firmly grounds this effort in its educational mission.", "east": 167.5, "geometry": "POINT(167.25 -77.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS", "is_usap_dc": true, "keywords": "Ice Caves; USAP-DC; Amd/Us; Distributed Temperature Sensing; FIELD SURVEYS; Not provided; AMD; Optical Fiber", "locations": null, "north": -77.3, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kyle, Philip; Curtis, Aaron; Rotman, Holly", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "MEVO", "south": -77.7, "title": "Mount Erebus Volcano Observatory III (MEVO III): Conduit Processes and Surveillance", "uid": "p0000488", "west": 167.0}, {"awards": "1355533 Dayton, Paul", "bounds_geometry": "POLYGON((163 -78,163.4 -78,163.8 -78,164.2 -78,164.6 -78,165 -78,165.4 -78,165.8 -78,166.2 -78,166.6 -78,167 -78,167 -78.05,167 -78.1,167 -78.15,167 -78.2,167 -78.25,167 -78.3,167 -78.35,167 -78.4,167 -78.45,167 -78.5,166.6 -78.5,166.2 -78.5,165.8 -78.5,165.4 -78.5,165 -78.5,164.6 -78.5,164.2 -78.5,163.8 -78.5,163.4 -78.5,163 -78.5,163 -78.45,163 -78.4,163 -78.35,163 -78.3,163 -78.25,163 -78.2,163 -78.15,163 -78.1,163 -78.05,163 -78))", "dataset_titles": "A Multi-decadal Record of Antarctic Benthos: Image Analysis to Maximize Data Utilization", "datasets": [{"dataset_uid": "600164", "doi": "10.15784/600164", "keywords": "Antarctica; Bentic Fauna; Biota; McMurdo Sound; Oceans; Ross Sea; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Dayton, Paul", "repository": "USAP-DC", "science_program": null, "title": "A Multi-decadal Record of Antarctic Benthos: Image Analysis to Maximize Data Utilization", "url": "https://www.usap-dc.org/view/dataset/600164"}], "date_created": "Tue, 31 May 2016 00:00:00 GMT", "description": "Antarctic benthic communities are characterized by many species of sponges (Phylum Porifera), long thought to exhibit extremely slow demographic patterns of settlement, growth and reproduction. This project will analyze many hundreds of diver and remotely operated underwater vehicle photographs documenting a unique, episodic settlement event that occurred between 2000 and 2010 in McMurdo Sound that challenges this paradigm of slow growth. Artificial structures were placed on the seafloor between 1967 and 1974 at several sites, but no sponges were observed to settle on these structures until 2004. By 2010 some 40 species of sponges had settled and grown to be surprisingly large. Given the paradigm of slow settlement and growth supported by the long observation period (37 years, 1967-2004), this extraordinary large-scale settlement and rapid growth over just a 6-year time span is astonishing. This project utilizes image processing software (ImageJ) to obtain metrics (linear dimensions to estimate size, frequency, percent cover) for sponges and other fauna visible in the photographs. It uses R to conduct multidimensional scaling to ordinate community data and ANOSIM to test for differences of community data among sites and times and structures. It will also use SIMPER and ranked species abundances to discriminate species responsible for any differences. \u003cbr/\u003e\u003cbr/\u003eThis work focuses on Antarctic sponges, but the observations of massive episodic recruitment and growth are important to understanding seafloor communities worldwide. Ecosystems are composed of populations, and populations are ecologically described by their distribution and abundance. A little appreciated fact is that sponges often dominate marine communities, but because sponges are so hard to study, most workers focus on other groups such as corals, kelps, or bivalves. Because most sponges settle and grow slowly their life history is virtually unstudied. The assumption of relative stasis of the Antarctic seafloor community is common, and this project will shatter this paradigm by documenting a dramatic episodic event. Finally, the project takes advantage of old transects from the 1960s and 1970s and compares them with extensive 2010 surveys of the same habitats and sometimes the same intact transect lines, offering a long-term perspective of community change. The investigators will publish these results in peer-reviewed journals, give presentations to the general public and will involve students from local outreach programs, high schools, and undergraduates at UCSD to help with the analysis.", "east": 167.0, "geometry": "POINT(165 -78.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -78.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Dayton, Paul", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.5, "title": "EAGER: A Multi-decadal Record of Antarctic Benthos: Image Analysis to Maximize Data Utilization", "uid": "p0000401", "west": 163.0}, {"awards": "1142052 MacPhee, Ross", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1602", "datasets": [{"dataset_uid": "002666", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1602", "url": "https://www.rvdata.us/search/cruise/NBP1602"}], "date_created": "Tue, 26 Apr 2016 00:00:00 GMT", "description": "The role that Antarctica has played in vertebrate evolution and paleobiogeography during the Late Cretaceous and early Paleogene is largely unknown. Evidence indicates that Antarctica was home to a diverse flora during the Late Cretaceous and Paleogene, yet the vertebrates that must have existed on the continent remain virtually unknown. To fill this gap, the PIs have formed the Antarctic Vertebrate Paleontology Initiative (AVPI), whose goal is to search for and collect Late Cretaceous-Paleogene vertebrate fossils in Antarctica at localities that have never been properly surveyed, as well as in areas of proven potential. Two field seasons are proposed for the James Ross Island Group on the northeastern margin of the Antarctic Peninsula. Expected finds include chondrichthyan and osteichthyan fishes, marine reptiles, ornithischian and non-avian theropod dinosaurs, ornithurine birds, and therian and non-therian mammals. Hypotheses to be tested include: 1) multiple extant bird and/or therian mammal lineages originated during the Cretaceous and survived the K-Pg boundary extinction event; 2) the ?Scotia Portal? permitted the dispersal of continental vertebrates between Antarctica and South America prior to the latest Cretaceous and through to the late Paleocene or early Eocene; 3) Late Cretaceous non-avian dinosaurs from Antarctica are closely related to coeval taxa from other Gondwanan landmasses; 4) terminal Cretaceous marine reptile faunas from southern Gondwana differed from contemporaneous but more northerly assemblages; and 5) the collapse of Antarctic ichthyofaunal diversity during the K-Pg transition was triggered by a catastrophic extinction.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe PIs will communicate discoveries to audiences through a variety of channels, such as the Dinosaurs in Their Time exhibition at Carnegie Museum of Natural History and the outreach programs of the Environmental Science Institute of the University of Texas at Austin. In addition, Carnegie Museum will launch a student-oriented programming initiative using AVPI research as a primary focus. This array of activities will help some 2,000 Pittsburgh-area undergraduates to explore the relevance of deep-time discoveries to critical modern issues. The AVPI will provide research opportunities for eight undergraduate and three graduate students, several of whom will receive field training in Antarctica. Fossils will be accessioned into the Carnegie Museum collection, and made accessible virtually through the NSF-funded Digital Morphology library at University of Texas.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Lamanna, Matthew", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Late Cretaceous-Paleogene Vertebrates from Antarctica: Implications for Paleobiogeography, Paleoenvironment, and Extinction in Polar Gondwana", "uid": "p0000854", "west": null}, {"awards": "0838936 Brook, Edward J.; 0839031 Severinghaus, Jeffrey", "bounds_geometry": "POINT(161.75 -77.75)", "dataset_titles": "Measurements of 14C-methane for the Younger Dryas - Preboreal Transition from Taylor Glacier, Antarctica; Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica; Taylor Glacier chemistry data and Taylor Dome TD2015 time scale; Taylor Glacier CO2 record; Taylor Glacier Gas Isotope Data", "datasets": [{"dataset_uid": "601103", "doi": "10.15784/601103", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Horizontal Ice Core; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Taylor Glacier chemistry data and Taylor Dome TD2015 time scale", "url": "https://www.usap-dc.org/view/dataset/601103"}, {"dataset_uid": "601029", "doi": "10.15784/601029", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Critical Zone; Geochemistry; Methane; Paleoclimate; Sample/collection Description; Sample/Collection Description; Solid Earth; Taylor Glacier; Transantarctic Mountains; Younger Dryas", "people": "Petrenko, Vasilii; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Measurements of 14C-methane for the Younger Dryas - Preboreal Transition from Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601029"}, {"dataset_uid": "000158", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Taylor Glacier CO2 record", "url": "ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/taylor/taylor2016d13co2.txt"}, {"dataset_uid": "601033", "doi": "10.15784/601033", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciology; Ice Core Records; Isotope; Solid Earth; Taylor Glacier; Transantarctic Mountains", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Taylor Glacier Gas Isotope Data", "url": "https://www.usap-dc.org/view/dataset/601033"}, {"dataset_uid": "600165", "doi": "10.15784/600165", "keywords": "Antarctica; Cosmogenic; Geochemistry; Ice Core Records; Paleoclimate; Radiocarbon; Taylor Glacier; Transantarctic Mountains", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600165"}], "date_created": "Tue, 29 Mar 2016 00:00:00 GMT", "description": "Severinghaus/0839031 \u003cbr/\u003e\u003cbr/\u003eThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop a precise gas-based chronology for an archive of large-volume samples of the ancient atmosphere, which would enable ultra-trace gas measurements that are currently precluded by sample size limitations of ice cores. The intellectual merit of the proposed work is that it will provide a critical test of the \"clathrate hypothesis\" that methane clathrates contributed to the two abrupt atmospheric methane concentration increases during the last deglaciation 15 and 11 kyr ago. This approach employs large volumes of ice (\u003e1 ton) to measure carbon-14 on past atmospheric methane across the abrupt events. Carbon-14 is an ideal discriminator of fossil sources of methane to the atmosphere, because most methane sources (e.g., wetlands, termites, biomass burning) are rich in carbon-14, whereas clathrates and other fossil sources are devoid of carbon-14. The proposed work is a logical extension to Taylor Glacier, Antarctica, of an approach pioneered at the margin of the Greenland ice sheet over the past 7 years. The Greenland work found higher-than-expected carbon-14 values, likely due in part to contaminants stemming from the high impurity content of Greenland ice and the interaction of the ice with sediments from the glacier bed. The data also pointed to the possibility of a previously unknown process, in-situ cosmogenic production of carbon-14 methane (radiomethane) in the ice matrix. Antarctic ice in Taylor Glacier is orders of magnitude cleaner than the ice at the Greenland site, and is much colder and less stratigraphically disturbed, offering the potential for a clear resolution of this puzzle and a definitive test of the cosmogenic radiomethane hypothesis. Even if cosmogenic radiomethane in ice is found, it still may be possible to reconstruct atmospheric radiomethane with a correction enabled by a detailed understanding of the process, which will be sought by co-measuring carbon-14 in carbon monoxide and carbon dioxide. The broader impacts of the proposed work are that the clathrate test may shed light on the stability of the clathrate reservoir and its potential for climate feedbacks under human-induced warming. Development of Taylor Glacier as a \"horizontal ice core\" would provide a community resource for other researchers. Education of one postdoc, one graduate student, and one undergraduate, would add to human resources. This award has field work in Antarctica.", "east": 161.75, "geometry": "POINT(161.75 -77.75)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; Not provided; USAP-DC", "locations": null, "north": -77.75, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Brook, Edward J.; Severinghaus, Jeffrey P.", "platforms": "Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "NCEI; USAP-DC", "science_programs": null, "south": -77.75, "title": "Collaborative Research: A \"Horizontal Ice Core\" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica", "uid": "p0000099", "west": 161.75}, {"awards": "1043145 Obbard, Rachel", "bounds_geometry": "POLYGON((164.1005 -77.1188,164.36443 -77.1188,164.62836 -77.1188,164.89229 -77.1188,165.15622 -77.1188,165.42015 -77.1188,165.68408 -77.1188,165.94801 -77.1188,166.21194 -77.1188,166.47587 -77.1188,166.7398 -77.1188,166.7398 -77.19337,166.7398 -77.26794,166.7398 -77.34251,166.7398 -77.41708,166.7398 -77.49165,166.7398 -77.56622,166.7398 -77.64079,166.7398 -77.71536,166.7398 -77.78993,166.7398 -77.8645,166.47587 -77.8645,166.21194 -77.8645,165.94801 -77.8645,165.68408 -77.8645,165.42015 -77.8645,165.15622 -77.8645,164.89229 -77.8645,164.62836 -77.8645,164.36443 -77.8645,164.1005 -77.8645,164.1005 -77.78993,164.1005 -77.71536,164.1005 -77.64079,164.1005 -77.56622,164.1005 -77.49165,164.1005 -77.41708,164.1005 -77.34251,164.1005 -77.26794,164.1005 -77.19337,164.1005 -77.1188))", "dataset_titles": "Bromide in Snow in the Sea Ice Zone", "datasets": [{"dataset_uid": "600158", "doi": "10.15784/600158", "keywords": "Atmosphere; Chemistry:ice; Chemistry:Ice; Critical Zone; Crystals; Glaciology; Oceans; Photo/video; Photo/Video; Ross Sea; Sea Ice; Sea Surface; Snow; Southern Ocean", "people": "Obbard, Rachel", "repository": "USAP-DC", "science_program": null, "title": "Bromide in Snow in the Sea Ice Zone", "url": "https://www.usap-dc.org/view/dataset/600158"}], "date_created": "Tue, 01 Mar 2016 00:00:00 GMT", "description": "A range of chemical and microphysical pathways in polar latitudes, including spring time (tropospheric) ozone depletion, oxidative pathways for mercury, and cloud condensation nuclei (CCN) production leading to changes in the cloud cover and attendant surface energy budgets, have been invoked as being dependent upon the emission of halogen gases formed in sea-ice. \u003cbr/\u003e\u003cbr/\u003eThe prospects for climate warming induced reductions in sea ice extent causing alteration of these incompletely known surface-atmospheric feedbacks and interactions requires confirmation of mechanistic details in both laboratory studies and field campaigns. One such mechanistic question is how bromine (BrO and Br) enriched snow migrates or is formed through processes in sea-ice, prior to its subsequent mobilization as an aerosol fraction into the atmosphere by strong winds. Once aloft, it may react with ozone and other atmospheric species. Dartmouth researchers will collect snow from the surface of sea ice, from freely blowing snow and in sea-ice cores from Cape Byrd, Ross Sea. A range of spectroscopic, microanalytic and and microstructural approaches will be subsequently used to determine the Br distribution gradients through sea-ice, in order to shed light on how sea-ice first forms and then releases bromine species into the polar atmospheric boundary layer.", "east": 166.7398, "geometry": "POINT(165.42015 -77.49165)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.1188, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Obbard, Rachel", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.8645, "title": "Bromide in Snow in the Sea Ice Zone", "uid": "p0000414", "west": 164.1005}, {"awards": "1043152 Cottle, John", "bounds_geometry": "POINT(162.66667 -78.16667)", "dataset_titles": "EarthChem Library #925.", "datasets": [{"dataset_uid": "000167", "doi": "", "keywords": null, "people": null, "repository": "EarthChem", "science_program": null, "title": "EarthChem Library #925.", "url": "http://www.earthchem.org/library/browse/view?id=925"}], "date_created": "Tue, 01 Mar 2016 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eMagmas generated during subduction of oceanic lithosphere beneath active continental margins typically have a calc-alkaline chemistry. However, igneous rocks with signatures usually associated with anorogenic magmatism are increasingly being found with calc-alkaline rocks in subduction zones. These enigmatic rocks provide insight into a variety of magmatic and structural processes that are fundamental to subduction zone dynamics but processes that lead to their petrogenesis remain a matter of debate. This project will investigate the Koettlitz Glacier Alkaline Province (KGAP) in the Transantarctic Mountains, which is a section through a Na-alkaline province bounded to the north and south by calc-alkaline magmatism. This province potentially contains key information on the thermo-mechanical processes leading to generation of Na-alkaline rocks in subduction systems. The PI will examine structures that bound the KGAP as well as intrusives and metasedimentary rocks contained within it to determine the tectonomagmatic history in the framework of two end-member hypotheses: the KGAP represents a crustal-scale extensional or transtensional domain in a subduction setting; or the KGAP formed in response to ridge subduction. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis study will train three graduate and three undergraduate students incorporating hands-on experience with state of the art instrumentation. Each summer, four high school students will be incorporated into various aspects of the laboratory-based research through the UCSB research mentorship program. This project will stimulate refinement of in-situ LA-ICPMS methods and development of collaborative linkages with Antarctic geologists at GNS Science in New Zealand. Results will be disseminated via papers and presentations at international conferences.", "east": 162.66667, "geometry": "POINT(162.66667 -78.16667)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -78.16667, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Cottle, John", "platforms": "Not provided", "repo": "EarthChem", "repositories": "EarthChem", "science_programs": null, "south": -78.16667, "title": "Exploring the Significance of Na-Alkaline Magmatism in Subduction Systems, a Case Study From the Ross Orogen, Antarctica", "uid": "p0000331", "west": 162.66667}, {"awards": "1043649 Hock, Regine", "bounds_geometry": null, "dataset_titles": "King George and Livingston Islands: Velocities and Digital Elevation Model", "datasets": [{"dataset_uid": "609667", "doi": "10.7265/N5R49NR1", "keywords": "Antarctica; Antarctic Peninsula; Digital Elevation Model; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Thickness; Ice Velocity", "people": "Hock, Regine; Osmanoglu, Batuhan", "repository": "USAP-DC", "science_program": null, "title": "King George and Livingston Islands: Velocities and Digital Elevation Model", "url": "https://www.usap-dc.org/view/dataset/609667"}], "date_created": "Wed, 17 Feb 2016 00:00:00 GMT", "description": "1043649/Braun\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to determine the current mass balance of selected glaciers of the Western Antarctic Peninsula (WAP) and adjacent islands, including King George Island and Livingston Island. A major goal is to discriminate the climatic and dynamic components of the current mass budget. The dynamic component will be assessed using a flux gate approach. Glacier velocity fields will be derived by offset tracking on repeat SAR satellite imagery, and ice thicknesses across grounding lines or near terminus will be approximated from a new methods based on mass continuity. The surface mass balance will be computed from a spatially distributed temperature-index mass-balance model forced by temperature and precipitation data from regional climate models. Our results will provide improved mass budget estimates of Western Antarctic Peninsula glaciers and a more thorough understanding of the ratio between the climatic and dynamic components. The techniques to be developed will be applicable to other glaciers in the region allowing regional scale mass budgets to be derived. The broader impacts of this work are that glacier wastage is currently the most important contributor to global sea level rise and the Antarctic Peninsula has been identified as one of the largest single contributors. Future sea-level rise has major societal, economic and ecological implications. The activity will foster new partnerships through collaboration with European and South American colleagues. The project will form the base of of a postdoctoral research fellowship. It will also provide training of undergraduate and graduate students through inclusion of data and results in course curriculums.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e PALSAR", "is_usap_dc": true, "keywords": "ALOS; Digital Elevation Model", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Glaciology", "paleo_time": null, "persons": "Hock, Regine; Osmanoglu, Batuhan", "platforms": "SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e ADVANCED LAND OBSERVING SATELLITE (ALOS) \u003e ALOS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Contribution of Western Antarctic Peninsula glaciers to sea level rise: Separation of the dynamic and climatic components", "uid": "p0000054", "west": null}, {"awards": "1141326 Rotella, Jay", "bounds_geometry": "POLYGON((163.1 -70.3,163.59 -70.3,164.08 -70.3,164.57 -70.3,165.06 -70.3,165.55 -70.3,166.04 -70.3,166.53 -70.3,167.02 -70.3,167.51 -70.3,168 -70.3,168 -70.98,168 -71.66,168 -72.34,168 -73.02,168 -73.7,168 -74.38,168 -75.06,168 -75.74,168 -76.42,168 -77.1,167.51 -77.1,167.02 -77.1,166.53 -77.1,166.04 -77.1,165.55 -77.1,165.06 -77.1,164.57 -77.1,164.08 -77.1,163.59 -77.1,163.1 -77.1,163.1 -76.42,163.1 -75.74,163.1 -75.06,163.1 -74.38,163.1 -73.7,163.1 -73.02,163.1 -72.34,163.1 -71.66,163.1 -70.98,163.1 -70.3))", "dataset_titles": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2017 Antarctic field season", "datasets": [{"dataset_uid": "601125", "doi": "10.15784/601125", "keywords": "Antarctica; Biota; Sea Ice", "people": "Rotella, Jay", "repository": "USAP-DC", "science_program": null, "title": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2017 Antarctic field season", "url": "https://www.usap-dc.org/view/dataset/601125"}], "date_created": "Mon, 08 Feb 2016 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe Erebus Bay population of Weddell seals in Antarctica?s Ross Sea is the most southerly breeding population of mammal in the world, closely associated with persistent shore-fast ice, and one that has been intensively studied since 1968. The resulting long-term database, which includes data for 20,586 marked individuals, contains detailed population information that provides an excellent opportunity to study linkages between environmental conditions and demographic processes in the Antarctic. The population?s location is of special interest as the Ross Sea is one of the most productive areas of the Southern Ocean, one of the few pristine marine environments remaining on the planet, and, in contrast to the Antarctic Peninsula and Arctic, is undergoing a gradual lengthening of the sea-ice season.\u003cbr/\u003eThe work to be continued here capitalizes on (1) long-term data for individual seals and their polar environment; (2) experience collecting and analyzing data from the extensive study population; and (3) recent statistical advances in hierarchical modeling that allow for rigorous treatment of individual heterogeneity (in mark-recapture and body mass data) and inclusion of diverse covariates hypothesized to explain variation in fitness components. Covariates to be considered include traits of individuals and their mothers and environmental conditions throughout life. \u003cbr/\u003e\u003cbr/\u003eThe study will continue to (1) provide detailed data on known-age individuals to other science projects and (2) educate and mentor the next generation of ecologists through academic and professional training and research experiences.", "east": 168.0, "geometry": "POINT(165.55 -73.7)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -70.3, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rotella, Jay; Garrott, Robert", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.1, "title": "The Demographic Consequences of Environmental Variability and Individual Heterogeneity in Life-history Tactics of a Long-lived Antarctic Marine Predator", "uid": "p0000299", "west": 163.1}, {"awards": "1063592 Arrigo, Kevin", "bounds_geometry": "POLYGON((-75.8 -61.08,-74.457 -61.08,-73.114 -61.08,-71.771 -61.08,-70.428 -61.08,-69.085 -61.08,-67.742 -61.08,-66.399 -61.08,-65.056 -61.08,-63.713 -61.08,-62.37 -61.08,-62.37 -61.684,-62.37 -62.288,-62.37 -62.892,-62.37 -63.496,-62.37 -64.1,-62.37 -64.704,-62.37 -65.308,-62.37 -65.912,-62.37 -66.516,-62.37 -67.12,-63.713 -67.12,-65.056 -67.12,-66.399 -67.12,-67.742 -67.12,-69.085 -67.12,-70.428 -67.12,-71.771 -67.12,-73.114 -67.12,-74.457 -67.12,-75.8 -67.12,-75.8 -66.516,-75.8 -65.912,-75.8 -65.308,-75.8 -64.704,-75.8 -64.1,-75.8 -63.496,-75.8 -62.892,-75.8 -62.288,-75.8 -61.684,-75.8 -61.08))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 11 Jan 2016 00:00:00 GMT", "description": "Phaeocystis antarctica is capable of forming blooms that are denser and more extensive than any other member of the Southern Ocean phytoplankton community. The factors that enable P Antarctica to dominate its competitors are not clear but are likely related to its colonial lifestyle. The goal of the project is to map all the reactions in metabolic pathways that are key to defining the ecological niche of Phaeocystis antarctica by developing a Pathway/Genome Database (PGDB) using Pathway Tools software. The investigators will assign proteins and enzymes to key pathways in P. Antarctica, continually improve and edit the database as the full Phaeocystis genome comes online, and host the database on the BioCyc webpage. The end product will be the first database for a eukaryotic phytoplankton genome where researchers can query extant metabolic pathways and place new proteins and enzymes of interest within metabolic networks. The risk is that a substantial percentage of catalytic enzymes may belong to pathways that are poorly characterized. The science impact is to link genomes to metabolic potential in the context of Phaeocystis life history but also in comparison to other organisms across the tree of life. The education and outreach includes work with a high school teacher and intern and curriculum development.", "east": -62.37, "geometry": "POINT(-69.085 -64.1)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -61.08, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Arrigo, Kevin", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -67.12, "title": "Application for an Early-concept Grant for Exploratory Reasearch (EAGER) to develop a Pathway/Genome Database (PGDB) for the Southern Ocean Haptophyte Phaeocystis Antarctica.", "uid": "p0000445", "west": -75.8}, {"awards": "0944659 Kiene, Ronald; 0944686 Kieber, David", "bounds_geometry": "POLYGON((-180 -68,-177 -68,-174 -68,-171 -68,-168 -68,-165 -68,-162 -68,-159 -68,-156 -68,-153 -68,-150 -68,-150 -69,-150 -70,-150 -71,-150 -72,-150 -73,-150 -74,-150 -75,-150 -76,-150 -77,-150 -78,-153 -78,-156 -78,-159 -78,-162 -78,-165 -78,-168 -78,-171 -78,-174 -78,-177 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -77,160 -76,160 -75,160 -74,160 -73,160 -72,160 -71,160 -70,160 -69,160 -68,162 -68,164 -68,166 -68,168 -68,170 -68,172 -68,174 -68,176 -68,178 -68,-180 -68))", "dataset_titles": "Ecophysiology of DMSP and related compounds and their contributions to carbon and sulfur dynamics in Phaeocystis antarctica", "datasets": [{"dataset_uid": "600117", "doi": "10.15784/600117", "keywords": "Biota; Ross Sea; Southern Ocean", "people": "Kieber, David John", "repository": "USAP-DC", "science_program": null, "title": "Ecophysiology of DMSP and related compounds and their contributions to carbon and sulfur dynamics in Phaeocystis antarctica", "url": "https://www.usap-dc.org/view/dataset/600117"}, {"dataset_uid": "600150", "doi": "10.15784/600150", "keywords": "Antarctica; Biota; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Oceans; Ross Sea", "people": "Kiene, Ronald", "repository": "USAP-DC", "science_program": null, "title": "Ecophysiology of DMSP and related compounds and their contributions to carbon and sulfur dynamics in Phaeocystis antarctica", "url": "https://www.usap-dc.org/view/dataset/600150"}], "date_created": "Wed, 16 Dec 2015 00:00:00 GMT", "description": "Spectacular blooms of Phaeocystis antarctica in the Ross Sea, Antarctica are the source of some of the world\u0027s highest concentrations of dimethylsulfoniopropionate (DMSP) and its volatile degradation product, dimethylsulfide (DMS). The flux of DMS from the oceans to the atmosphere in this region and its subsequent gas phase oxidation generates aerosols that have a strong influence on cloud properties and possibly climate. In the oceans, DMS and DMSP are quantitatively significant components of the carbon, sulfur, and energy flows in marine food webs, especially in the Ross Sea. Despite its central role in carbon and sulfur biogeochemistry in the Ross Sea, surprisingly little is known about the physiological functions of DMSP in P. Antarctica. The research will isolate and characterize DMSP lyases from P. antarctica, with the goal of obtaining amino acid and gene sequence information on these important enzymes. The physiological studies will focus on the effects of varying intensities of photosynthetically active radiation, with and without ultraviolet radiation as these are factors that we have found to be important controls on DMSP and DMS dynamics. The research also will examine the effects of prolonged darkness on the dynamics of DMSP and related compounds in P. antarctica, as survival of this species during the dark Antarctic winter and at sub-euphotic depths appears to be an important part of the Phaeocystis? ecology. A unique aspect of this work is the focus on measurements of intracellular MSA, which if detected, would provide strong evidence for in vivo radical scavenging functions for methyl sulfur compounds. The study will advance understanding of what controls DMSP cycling and ultimately DMS emissions from the Ross Sea and also provide information on what makes P. antarctica so successful in this extreme environment. The research will directly benefit and build on several interrelated ocean-atmosphere programs including the International Surface Ocean Lower Atmosphere Study (SOLAS) program. The PIs will participate in several activities involving K-12 education, High School teacher training, public education and podcasting through the auspices of the Dauphin Island Sea Lab Discovery Hall program and SUNY ESF. Two graduate students will be employed full time, and six undergraduates (2 each summer) will be trained as part of this project.", "east": -150.0, "geometry": "POINT(-175 -73)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; Not provided; Ecophysiology; AMD; USAP-DC; FIELD SURVEYS", "locations": null, "north": -68.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kiene, Ronald; Kieber, David John", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Ecophysiology of DMSP and related compounds and their contributions to carbon and sulfur dynamics in Phaeocystis antarctica", "uid": "p0000085", "west": 160.0}, {"awards": "1142174 Smith, Walker; 1142074 Ballard, Grant", "bounds_geometry": "POLYGON((165.9 -76.9,166.25 -76.9,166.6 -76.9,166.95 -76.9,167.3 -76.9,167.65 -76.9,168 -76.9,168.35 -76.9,168.7 -76.9,169.05 -76.9,169.4 -76.9,169.4 -76.97,169.4 -77.04,169.4 -77.11,169.4 -77.18,169.4 -77.25,169.4 -77.32,169.4 -77.39,169.4 -77.46,169.4 -77.53,169.4 -77.6,169.05 -77.6,168.7 -77.6,168.35 -77.6,168 -77.6,167.65 -77.6,167.3 -77.6,166.95 -77.6,166.6 -77.6,166.25 -77.6,165.9 -77.6,165.9 -77.53,165.9 -77.46,165.9 -77.39,165.9 -77.32,165.9 -77.25,165.9 -77.18,165.9 -77.11,165.9 -77.04,165.9 -76.97,165.9 -76.9))", "dataset_titles": "Access to data; Experimental analyses of phytoplankton temperature response; Glider data from the southern Ross Sea collected from the iRobot Seaglider during the RVIB Nathaniel B. Palmer (AUV-SG-503-2012, NBP1210) cruises in 2012 (Penguin Glider project); Penguin Science file sharing site", "datasets": [{"dataset_uid": "601135", "doi": "10.15784/601135", "keywords": "Antarctica; Biota; Chlorophyll; Foraminifera; Growth; Phytoplankton; Plankton; Temperature", "people": "Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Experimental analyses of phytoplankton temperature response", "url": "https://www.usap-dc.org/view/dataset/601135"}, {"dataset_uid": "002740", "doi": null, "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Penguin Science file sharing site", "url": "https://data.pointblue.org/apps/penguin_science/"}, {"dataset_uid": "002575", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Glider data from the southern Ross Sea collected from the iRobot Seaglider during the RVIB Nathaniel B. Palmer (AUV-SG-503-2012, NBP1210) cruises in 2012 (Penguin Glider project)", "url": "https://www.bco-dmo.org/dataset/568868/data"}, {"dataset_uid": "001426", "doi": "", "keywords": null, "people": null, "repository": "CADC", "science_program": null, "title": "Access to data", "url": "http://data.prbo.org/apps/penguinscience/AllData/NSF-ANT-1142074/"}], "date_created": "Mon, 14 Dec 2015 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe Ross Sea is believed to contributes a huge portion (~1/3) of the primary productivity of the Southern Ocean and is home to a similar large portion of the top predators (e.g. 38% of Adelie, 28% of Emperor penguins) of the Antarctic sea ice ecosystem. The trophic pathways in this system are complex in both space and time. One scenario for the Ross Sea ecosystem is that diatoms are grazed by krill, which are in turn the preferred food of fish, penguins and other predators. Phaeocystis colonies, on the other hand lead to grazing by pteropods and other organisms that are a non-favoured food source for top predators. Remotely sensed chlorophyll, indicating all phytoplankton, is then suggested to be a relatively poor predictor of penguin foraging efforts. This is also consistent with notion that algal species composition is very important to penguin grazing pressure, mediated by krill, and perhaps resulting in selective depletion. \u003cbr/\u003e\u003cbr/\u003eThis collaborative research sets out to use an autonomous glider, equipped with a range of sensors, and informed by satellite chlorophyll imagery to be combined with 3-dimenisonal active penguin tracking to their preferred foraging sites. The effect of localized grazing pressure of krill on the appearance and disappearance of algal blooms will also be followed. Overall the objective of the research is to reconcile and explain several years of the study of the foraging habits and strategies of (top predator) penguins at the Cape Crozier site (Ross Island), with the dynamics of krill and their supporting algal food webs. The use of a glider to answer a primarily ecological questions is subject to moderate to high risk, and is potentially transformative.", "east": 169.4, "geometry": "POINT(167.65 -77.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; USAP-DC", "locations": null, "north": -76.9, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker; Ballard, Grant", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "BCO-DMO; CADC; Project website; USAP-DC", "science_programs": null, "south": -77.6, "title": "Collaborative Research: Penguin Foraging Reveals Phytoplankton Spatial Structure in the Ross Sea", "uid": "p0000322", "west": 165.9}, {"awards": "0944141 Ballard, Grant; 0944358 Dugger, Katie; 0944411 Ainley, David", "bounds_geometry": "POLYGON((165.9 -76.9,166.25 -76.9,166.6 -76.9,166.95 -76.9,167.3 -76.9,167.65 -76.9,168 -76.9,168.35 -76.9,168.7 -76.9,169.05 -76.9,169.4 -76.9,169.4 -76.97,169.4 -77.04,169.4 -77.11,169.4 -77.18,169.4 -77.25,169.4 -77.32,169.4 -77.39,169.4 -77.46,169.4 -77.53,169.4 -77.6,169.05 -77.6,168.7 -77.6,168.35 -77.6,168 -77.6,167.65 -77.6,167.3 -77.6,166.95 -77.6,166.6 -77.6,166.25 -77.6,165.9 -77.6,165.9 -77.53,165.9 -77.46,165.9 -77.39,165.9 -77.32,165.9 -77.25,165.9 -77.18,165.9 -77.11,165.9 -77.04,165.9 -76.97,165.9 -76.9))", "dataset_titles": "Adelie penguin banding data 1994-2009; Adelie penguin chick counts 1997-2009; Adelie penguin chick measurements 1996 - 2009; Adelie penguin diet data 1996 - 2009; Adelie penguin dive data 1999-2009; Adelie penguin Geolocation Sensor data 2003-2007; Adelie penguin resighting data 1997-2009; Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science; Adelie penguin satellite position data 2000-2009; Adelie penguin weighbridge data 1994-2009; Daily weather observations 1996-2009; Leopard Seal counts 1997-2009; PRBO/California Avian Data Center (CADC)", "datasets": [{"dataset_uid": "600006", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin chick measurements 1996 - 2009", "url": "https://www.usap-dc.org/view/dataset/600006"}, {"dataset_uid": "600008", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin diet data 1996 - 2009", "url": "https://www.usap-dc.org/view/dataset/600008"}, {"dataset_uid": "600009", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin Geolocation Sensor data 2003-2007", "url": "https://www.usap-dc.org/view/dataset/600009"}, {"dataset_uid": "000154", "doi": "", "keywords": null, "people": null, "repository": "CADC", "science_program": null, "title": "PRBO/California Avian Data Center (CADC)", "url": "http://data.prbo.org/apps/penguinscience/"}, {"dataset_uid": "601444", "doi": "10.15784/601444", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Mark-Recapture; Monitoring; Penguin; Ross Island", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601444"}, {"dataset_uid": "600015", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Daily weather observations 1996-2009", "url": "https://www.usap-dc.org/view/dataset/600015"}, {"dataset_uid": "600014", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin weighbridge data 1994-2009", "url": "https://www.usap-dc.org/view/dataset/600014"}, {"dataset_uid": "600013", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin dive data 1999-2009", "url": "https://www.usap-dc.org/view/dataset/600013"}, {"dataset_uid": "600012", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin satellite position data 2000-2009", "url": "https://www.usap-dc.org/view/dataset/600012"}, {"dataset_uid": "600011", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin resighting data 1997-2009", "url": "https://www.usap-dc.org/view/dataset/600011"}, {"dataset_uid": "600010", "doi": "", "keywords": "Biota; Oceans", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Leopard Seal counts 1997-2009", "url": "https://www.usap-dc.org/view/dataset/600010"}, {"dataset_uid": "600005", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin banding data 1994-2009", "url": "https://www.usap-dc.org/view/dataset/600005"}, {"dataset_uid": "600007", "doi": "", "keywords": "Biota", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin chick counts 1997-2009", "url": "https://www.usap-dc.org/view/dataset/600007"}], "date_created": "Sun, 13 Dec 2015 00:00:00 GMT", "description": "While changes in populations typically are tracked to gauge the impact of climate or habitat change, the process involves the response of individuals as each copes with an altered environment. In a study of Adelie penguins that spans 13 breeding seasons, results indicate that only 20% of individuals within a colony successfully raise offspring, and that they do so because of their exemplary foraging proficiency. Moreover, foraging appears to require more effort at the largest colony, where intraspecific competition is higher than at small colonies, and also requires more proficiency during periods of environmental stress. When conditions are particularly daunting, emigration dramatically increases, countering the long-standing assumption that Ad\u00e9lie penguins are highly philopatric. The research project will 1) determine the effect of age, experience and physiology on individual foraging efficiency; 2) determine the effect of age, experience, and individual quality on breeding success and survival in varying environmental and competitive conditions at the colony level; and 3) develop a comprehensive model for the Ross-Beaufort Island metapopulation dynamics. Broader impacts include training of interns, continuation of public outreach through the highly successful project website penguinscience.com, development of classroom materials and other standards-based instructional resources.", "east": 169.4, "geometry": "POINT(167.65 -77.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.9, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ainley, David; Dugger, Katie; Ballard, Grant", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "CADC; USAP-DC", "science_programs": null, "south": -77.6, "title": "COLLABORATIVE: Adelie Penguin Response to Climate Change at the Individual, Colony and Metapopulation Levels", "uid": "p0000318", "west": 165.9}, {"awards": "1043454 Kooyman, Gerald", "bounds_geometry": "POLYGON((-172.642 -72.55,-170.9074 -72.55,-169.1728 -72.55,-167.4382 -72.55,-165.7036 -72.55,-163.969 -72.55,-162.2344 -72.55,-160.4998 -72.55,-158.7652 -72.55,-157.0306 -72.55,-155.296 -72.55,-155.296 -73.0743,-155.296 -73.5986,-155.296 -74.1229,-155.296 -74.6472,-155.296 -75.1715,-155.296 -75.6958,-155.296 -76.2201,-155.296 -76.7444,-155.296 -77.2687,-155.296 -77.793,-157.0306 -77.793,-158.7652 -77.793,-160.4998 -77.793,-162.2344 -77.793,-163.969 -77.793,-165.7036 -77.793,-167.4382 -77.793,-169.1728 -77.793,-170.9074 -77.793,-172.642 -77.793,-172.642 -77.2687,-172.642 -76.7444,-172.642 -76.2201,-172.642 -75.6958,-172.642 -75.1715,-172.642 -74.6472,-172.642 -74.1229,-172.642 -73.5986,-172.642 -73.0743,-172.642 -72.55))", "dataset_titles": "NBP1302 data; Pre and Post Molt Biology of Emperor Penguins - Oden Trans - Ross / Amundsen Sea Cruise", "datasets": [{"dataset_uid": "000179", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1302 data", "url": "https://www.rvdata.us/search/cruise/NBP1302"}, {"dataset_uid": "600149", "doi": "10.15784/600149", "keywords": "Amundsen Sea; Biota; Oceans; Penguin; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Kooyman, Gerald", "repository": "USAP-DC", "science_program": null, "title": "Pre and Post Molt Biology of Emperor Penguins - Oden Trans - Ross / Amundsen Sea Cruise", "url": "https://www.usap-dc.org/view/dataset/600149"}], "date_created": "Sat, 12 Dec 2015 00:00:00 GMT", "description": "The emperor penguin dives deeper and longer, fasts longer, and endures the harshest weather conditions of all diving birds. It spends about four and half months per annum deep in Antarctic pack ice away from shore and stations, and thus is largely unavailable for study. This time includes preparation for the molt, and travel to the colony to breed, a time period in which great swings in body weight occur. This study will fill an important gap in what we know about the biology of the annual cycle of the emperor by examining the molt-post molt period. The P.I. proposes to traverse the Amundsen and Bellingshausen seas on the Oden, to locate and tag emperor penguins during the molt season. The objectives are to (1) Place satellite tags on 20 adult post molt birds to determine their route, rate of travel, and diving behavior as they return back to their breeding colonies, (2) Obtain an index of body condition, (3) Collect guano to determine the type of food consumed by emperor penguins in the region, (4) Conduct shipboard surveys to sight and plot the location and abundance of adult and juvenile birds on the ship\u0027s track. The PI hypothesizes that bird dives will be shallow during the initial post-molt phase, and that food will consist primarily of krill; that there will be differential dispersal of birds from the Ross Sea vs. Marie Byrd Land, with Ross Sea birds traveling farther; and that the greatest adult mortality occurs during the molt and early post molt period. Broader impacts include training of a post doc, a graduate student, and an aquarium volunteer. The P.I. also will present findings through a website, through public lectures, and in collaboration with the Birch aquarium.", "east": -155.296, "geometry": "POINT(-163.969 -75.1715)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "R/V NBP; Not provided", "locations": null, "north": -72.55, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kooyman, Gerald", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -77.793, "title": "Pre and post molt biology of emperor penguins - Oden trans - Ross / Amundsen Sea cruise", "uid": "p0000325", "west": -172.642}, {"awards": "0944653 Forster, Richard", "bounds_geometry": "POLYGON((-119.4 -78.1,-118.46000000000001 -78.1,-117.52000000000001 -78.1,-116.58 -78.1,-115.64 -78.1,-114.7 -78.1,-113.76 -78.1,-112.82000000000001 -78.1,-111.88 -78.1,-110.94 -78.1,-110 -78.1,-110 -78.28999999999999,-110 -78.47999999999999,-110 -78.67,-110 -78.86,-110 -79.05,-110 -79.24,-110 -79.42999999999999,-110 -79.62,-110 -79.81,-110 -80,-110.94 -80,-111.88 -80,-112.82000000000001 -80,-113.76 -80,-114.7 -80,-115.64 -80,-116.58 -80,-117.52000000000001 -80,-118.46000000000001 -80,-119.4 -80,-119.4 -79.81,-119.4 -79.62,-119.4 -79.42999999999999,-119.4 -79.24,-119.4 -79.05,-119.4 -78.86,-119.4 -78.67,-119.4 -78.47999999999999,-119.4 -78.28999999999999,-119.4 -78.1))", "dataset_titles": "Annual Satellite Era Accumulation Patterns Over WAIS Divide: A Study Using Shallow Ice Cores, Near-Surface Radars and Satellites", "datasets": [{"dataset_uid": "600146", "doi": "10.15784/600146", "keywords": "Airborne Radar; Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Radar; WAIS Divide; WAIS Divide Ice Core", "people": "Forster, Richard", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Annual Satellite Era Accumulation Patterns Over WAIS Divide: A Study Using Shallow Ice Cores, Near-Surface Radars and Satellites", "url": "https://www.usap-dc.org/view/dataset/600146"}], "date_created": "Fri, 20 Nov 2015 00:00:00 GMT", "description": "This award supports a project to broaden the knowledge of annual accumulation patterns over the West Antarctic Ice Sheet by processing existing near-surface radar data taken on the US ITASE traverse in 2000 and by gathering and validating new ultra/super-high-frequency (UHF) radar images of near surface layers (to depths of ~15 m), expanding abilities to monitor recent annual accumulation patterns from point source ice cores to radar lines. Shallow (15 m) ice cores will be collected in conjunction with UHF radar images to confirm that radar echoed returns correspond with annual layers, and/or sub-annual density changes in the near-surface snow, as determined from ice core stable isotopes. This project will additionally improve accumulation monitoring from space-borne instruments by comparing the spatial-radar-derived-annual accumulation time series to the passive microwave time series dating back over 3 decades and covering most of Antarctica. The intellectual merit of this project is that mapping the spatial and temporal variations in accumulation rates over the Antarctic ice sheet is essential for understanding ice sheet responses to climate forcing. Antarctic precipitation rate is projected to increase up to 20% in the coming century from the predicted warming. Accumulation is a key component for determining ice sheet mass balance and, hence, sea level rise, yet our ability to measure annual accumulation variability over the past 5 decades (satellite era) is mostly limited to point-source ice cores. Developing a radar and ice core derived annual accumulation dataset will provide validation data for space-born remote sensing algorithms, climate models and, additionally, establish accumulation trends. The broader impacts of the project are that it will advance discovery and understanding within the climatology, glaciology and remote sensing communities by verifying the use of UHF radars to monitor annual layers as determined by visual, chemical and isotopic analysis from corresponding shallow ice cores and will provide a dataset of annual to near-annual accumulation measurements over the past ~5 decades across WAIS divide from existing radar data and proposed radar data. By determining if temporal changes in the passive microwave signal are correlated with temporal changes in accumulation will help assess the utility of passive microwave remote sensing to monitor accumulation rates over ice sheets for future decades. The project will promote teaching, training and learning, and increase representation of underrepresented groups by becoming involved in the NASA History of Winter project and Thermochron Mission and by providing K-12 teachers with training to monitor snow accumulation and temperature here in the US, linking polar research to the student?s backyard. The project will train both undergraduate and graduate students in polar research and will encouraging young investigators to become involved in careers in science. In particular, two REU students will participate in original research projects as part of this larger project, from development of a hypothesis to presentation and publication of the results. The support of a new, young woman scientist will help to increase gender diversity in polar research.", "east": -110.0, "geometry": "POINT(-114.7 -79.05)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -78.1, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Forster, Richard", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -80.0, "title": "Collaborative Research: Annual satellite era accumulation patterns over WAIS Divide: A study using shallow ice cores, near-surface radars and satellites", "uid": "p0000079", "west": -119.4}, {"awards": "1042883 Mayewski, Paul", "bounds_geometry": null, "dataset_titles": "LA-ICP-MS Results: 3 Siple Dome A Glacial Age Archives; Roosevelt Island Climate Evolution Ice Core ICP-MS data", "datasets": [{"dataset_uid": "609621", "doi": "10.7265/N52J68SQ", "keywords": "Antarctica; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; ICP-MS; Roosevelt Island; Ross Ice Shelf", "people": "Kurbatov, Andrei V.; Mayewski, Paul A.; Beers, Thomas M.", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Climate Evolution Ice Core ICP-MS data", "url": "https://www.usap-dc.org/view/dataset/609621"}, {"dataset_uid": "609636", "doi": "10.7265/N5WS8R6H", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; ICP-MS; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Kurbatov, Andrei V.; Haines, Skylar; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "LA-ICP-MS Results: 3 Siple Dome A Glacial Age Archives", "url": "https://www.usap-dc.org/view/dataset/609636"}], "date_created": "Tue, 27 Oct 2015 00:00:00 GMT", "description": "1042883/Mayewski\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to analyze a deep ice core which will be drilled by a New Zealand research team at Roosevelt Island. The objectives are to process the ice core at very high resolution to (a) better understand phasing sequences in Arctic/Antarctic abrupt climate change, even at the level of individual storm events; (b) determine the impact of changes in the Westerlies and the Amundsen Sea Low on past/present/future climate change; (c) determine how sea ice extent has varied in the area; (d) compare the response of West Antarctica climate to other regions during glacial/interglacial cycles; and (e) determine how climate of the Ross Sea Embayment changed during the transition from Ross Ice Sheet to Ross Ice Shelf. The intellectual merit of the RICE deep ice core project is that it is expected to provide a 30kyr long (and possibly 150kyr long) extremely high-resolution view of climate change in the Ross Sea Embayment Region and data essential to test and understand critical questions that have emerged as a consequence of the recent synthesis of Antarctic and Southern Ocean climate change presented in the Scientific Commission for Antarctic Research document: Antarctic Climate Change and the Environment (ACCE, 2009). Ice core processing and analysis will be performed jointly by University of Maine and the collaborators from New Zealand. Co-registered sampling for all chemical analyses will be accomplished by a joint laboratory effort at the IGNS NZ ice core facility using a continuous melter system developed by the University of Maine. The RICE deep ice core record will provide information necessary in unraveling the significance of multi-millennial underpinning for climate change and in the understanding of observed and projected climate change in light of current dramatic human impact on Antarctica and the Southern Ocean. The broader impacts of the project include the fact that two CCI graduate students will be funded through the project, and will be involved in all aspects of field research, core sampling, sample processing, analytical and numerical analyses, data interpretation, writing of manuscripts, and presentation of results at national and international conferences. Data and ideas developed in this project and associated work will be used in several courses taught at the University of Maine. Innovative cyberinfrastructure will be incorporated into this work and ground breaking analytical technologies, and data access/storage tools will be used.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e LA-ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS", "is_usap_dc": true, "keywords": "LABORATORY", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Haines, Skylar; Kurbatov, Andrei V.; Mayewski, Paul A.; Beers, Thomas M.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Roosevelt Island Climate Evolution Project (RICE): US Deep Ice Core Glaciochemistry Contribution (2011- 2014)", "uid": "p0000193", "west": null}, {"awards": "1142156 Marschall, Horst", "bounds_geometry": "POLYGON((-6.44 -71.93,-5.378 -71.93,-4.316 -71.93,-3.254 -71.93,-2.192 -71.93,-1.13 -71.93,-0.068 -71.93,0.994 -71.93,2.056 -71.93,3.118 -71.93,4.18 -71.93,4.18 -71.998,4.18 -72.066,4.18 -72.134,4.18 -72.202,4.18 -72.27,4.18 -72.338,4.18 -72.406,4.18 -72.474,4.18 -72.542,4.18 -72.61,3.118 -72.61,2.056 -72.61,0.994 -72.61,-0.068 -72.61,-1.13 -72.61,-2.192 -72.61,-3.254 -72.61,-4.316 -72.61,-5.378 -72.61,-6.44 -72.61,-6.44 -72.542,-6.44 -72.474,-6.44 -72.406,-6.44 -72.338,-6.44 -72.27,-6.44 -72.202,-6.44 -72.134,-6.44 -72.066,-6.44 -71.998,-6.44 -71.93))", "dataset_titles": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antarctica", "datasets": [{"dataset_uid": "600135", "doi": "10.15784/600135", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Dronning Maud Land; Geochemistry; Geochronology; Solid Earth", "people": "Marschall, Horst", "repository": "USAP-DC", "science_program": null, "title": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antarctica", "url": "https://www.usap-dc.org/view/dataset/600135"}], "date_created": "Fri, 23 Oct 2015 00:00:00 GMT", "description": "Geochemical studies of single mineral grains in rocks can be probed to reconstruct the history of our planet. The mineral zircon (ZrSiO4) is of unique importance in that respect because of its reliability as a geologic clock due to its strong persistence against weathering, transport and changes in temperature and pressure. Uranium-Lead (U-Pb) dating of zircon grains is, perhaps, the most frequently employed method of extracting time information on geologic processes that shaped the continental crust, and has been used to constrain the evolution of continents and mountain belts through time. In addition, the isotopic composition of the element Hafnium (Hf) in zircon is used to date when the continental crust was generated by extraction of magma from the underlying mantle. Melting of rocks in the mantle and deep in the continental crust are key processes in the evolution of the continents, and they are recorded in the Hf isotopic signatures of zircon. Although the analytical procedures for U-Pb dating and Hf isotope analyses of zircon are robust now, our understanding of zircon growth and its exchange of elements and isotopes with its surrounding rock or magma are still underdeveloped. The focus of the proposed study, therefore, is to unravel the evolution of zircon Hf isotopes in rocks that were formed deep in the Earth?s crust, and more specifically, to apply these isotopic methods to rocks collected in Dronning Maud Land (DML), East Antarctica.\u003cbr/\u003e\u003cbr/\u003eDronning Maud Land (DML) occupied a central location during the formation of supercontinents ? large landmasses made up of all the continents that exist today - more than 500 million years ago. It is currently thought that supercontinents were formed and dismembered five or six times throughout Earth?s history. The area of DML is key for understanding the formation history of the last two supercontinents. The boundaries of continents that were merged to form those supercontinents are most likely hidden in DML. In this study, the isotopic composition of zircon grains recovered from DML rocks will be employed to identify these boundaries across an extensive section through the area. The rock samples were collected by the investigator during a two-month expedition to Antarctica in the austral summer of 2007?2008. The results of dating and isotope analyses of zircon of the different DML crustal domains will deliver significant insight into the regional geology of East Antarctica and its previous northern extension into Africa. This has significance for the reconstruction of the supercontinents and defining the continental boundaries in DML.", "east": 4.18, "geometry": "POINT(-1.13 -72.27)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -71.93, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Marschall, Horst", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.61, "title": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antacrtica", "uid": "p0000448", "west": -6.44}, {"awards": "1343649 Levy, Joseph", "bounds_geometry": "POLYGON((162.852 -77.6111,162.9893 -77.6111,163.1266 -77.6111,163.2639 -77.6111,163.4012 -77.6111,163.5385 -77.6111,163.6758 -77.6111,163.8131 -77.6111,163.9504 -77.6111,164.0877 -77.6111,164.225 -77.6111,164.225 -77.65331,164.225 -77.69552,164.225 -77.73773,164.225 -77.77994,164.225 -77.82215,164.225 -77.86436,164.225 -77.90657,164.225 -77.94878,164.225 -77.99099,164.225 -78.0332,164.0877 -78.0332,163.9504 -78.0332,163.8131 -78.0332,163.6758 -78.0332,163.5385 -78.0332,163.4012 -78.0332,163.2639 -78.0332,163.1266 -78.0332,162.9893 -78.0332,162.852 -78.0332,162.852 -77.99099,162.852 -77.94878,162.852 -77.90657,162.852 -77.86436,162.852 -77.82215,162.852 -77.77994,162.852 -77.73773,162.852 -77.69552,162.852 -77.65331,162.852 -77.6111))", "dataset_titles": "Cryptic Hydrology of the McMurdo Dry Valleys: Water Track Contributions to Water and Geochemical Budgets in Taylor Valley, Antarctica", "datasets": [{"dataset_uid": "600139", "doi": "10.15784/600139", "keywords": "Antarctica; Chemistry:soil; Chemistry:Soil; Critical Zone; Dry Valleys; Permafrost; Sample/collection Description; Sample/Collection Description; Well Measurements", "people": "Levy, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Cryptic Hydrology of the McMurdo Dry Valleys: Water Track Contributions to Water and Geochemical Budgets in Taylor Valley, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600139"}], "date_created": "Mon, 05 Oct 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to quantify the hillslope water, solute, and carbon budgets for Taylor Valley in the McMurdo Dry Valleys, using water tracks to investigate near-surface geological processes and challenge the paradigm that shallow groundwater is minimal or non-exixtant. Water tracks are linear zones of high soil moisture that route shallow groundwater downslope in permafrost dominated soils. Four hypotheses will be tested: 1) water tracks are important pathways for water and solute transport; 2) water tracks transport more dissolved silica than streams in Taylor Valley indicating they are the primary site of chemical weathering for cold desert soils and bedrock; 3) water tracks that drain highland terrains are dominated by humidity-separated brines while water tracks that drain lowland terrains are dominated by marine aerosols; 4) water tracks are the sites of the highest terrestrial soil carbon concentrations and the strongest CO2 fluxes in Taylor Valley and their carbon content increases with soil age, while carbon flux decreases with age. To test these hypotheses the PIs will carry out a suite of field measurements supported by modeling and remote sensing. They will install shallow permafrost wells in water tracks that span the range of geological, climatological, and topographic conditions in Taylor Valley. Multifrequency electromagnetic induction sounding of the upper ~1 m of the permafrost will create the first comprehensive map of soil moisture in Taylor Valley, and will permit direct quantification of water track discharge across the valley. The carbon contents of water track soils will be measured and linked to global carbon dynamics.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eNon-science majors at Oregon State University will be integrated into the proposed research through a new Global Environmental Change course focusing on the scientific method in Antarctica. Three undergraduate students, members of underrepresented minorities, will be entrained in the research, will contribute to all aspects of field and laboratory science, and will present results at national meetings.", "east": 164.225, "geometry": "POINT(163.5385 -77.82215)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.6111, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Levy, Joseph", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0332, "title": "Cryptic Hydrology of the McMurdo Dry Valleys: Water Track Contributions to Water and Geochemical Budgets in Taylor Valley, Antarctica", "uid": "p0000407", "west": 162.852}, {"awards": "0739575 Emslie, Steven", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Egg membrane and chick feather THg concentration and stable isotope composition; Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica", "datasets": [{"dataset_uid": "600145", "doi": "10.15784/600145", "keywords": "Antarctica; Antarctic Peninsula; Biota; Geochronology; Global; Penguin; Ross Sea; Sample/collection Description; Sample/Collection Description; Scotia Sea; Southern Ocean", "people": "Polito, Michael; Patterson, William; Emslie, Steven", "repository": "USAP-DC", "science_program": null, "title": "Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica", "url": "https://www.usap-dc.org/view/dataset/600145"}, {"dataset_uid": "601459", "doi": "10.15784/601459", "keywords": "Adelie Penguin; Antarctica; Antarctic Peninsula; Mercury; Penguin", "people": "McKenzie, Ashley", "repository": "USAP-DC", "science_program": null, "title": "Egg membrane and chick feather THg concentration and stable isotope composition", "url": "https://www.usap-dc.org/view/dataset/601459"}], "date_created": "Fri, 25 Sep 2015 00:00:00 GMT", "description": "The research combines interdisciplinary study in geology, paleontology, and biology, using stable isotope and radiocarbon analyses, to examine how climate change and resource utilization have influenced population distribution, movement, and diet in penguins during the mid-to-late Holocene. Previous investigations have demonstrated that abandoned colonies contain well-preserved remains that can be used to examine differential responses of penguins to climate change in various sectors of Antarctica. As such, the research team will investigate abandoned and active pygoscelid penguin (Adelie, Chinstrap, and Gentoo) colonies in the Antarctic Peninsula and Ross Sea regions, and possibly Prydz Bay, in collaboration with Chinese scientists during four field seasons. Stable isotope analyses will be conducted on recovered penguin tissues and prey remains in guano to address hypotheses on penguin occupation history, population movement, and diet in relation to climate change since the late Pleistocene. The study will include one Ph.D., two Masters and 16 undergraduate students in advanced research over the project period. Students will be exposed to a variety of fields, the scientific method, and international scientific research. They will complete field and lab research for individual projects or Honor\u0027s theses for academic credit. The project also will include web-based outreach, lectures to middle school students, and the development of interactive exercises that highlight hypothesis-driven research and the ecology of Antarctica. Two undergraduate students in French and Spanish languages at UNCW will be hired to assist in translating the Web page postings for broader access to this information.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; AMD; USAP-DC; FIELD INVESTIGATION; Amd/Us", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Emslie, Steven; Polito, Michael; Patterson, William", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica", "uid": "p0000317", "west": -180.0}, {"awards": "1142065 DiTullio, Giacomo; 1142097 Bochdansky, Alexander; 1142044 Dunbar, Robert; 1142117 Hansell, Dennis", "bounds_geometry": "POLYGON((165 -52,166 -52,167 -52,168 -52,169 -52,170 -52,171 -52,172 -52,173 -52,174 -52,175 -52,175 -54.65,175 -57.3,175 -59.95,175 -62.6,175 -65.25,175 -67.9,175 -70.55,175 -73.2,175 -75.85,175 -78.5,174 -78.5,173 -78.5,172 -78.5,171 -78.5,170 -78.5,169 -78.5,168 -78.5,167 -78.5,166 -78.5,165 -78.5,165 -75.85,165 -73.2,165 -70.55,165 -67.9,165 -65.25,165 -62.6,165 -59.95,165 -57.3,165 -54.650000000000006,165 -52))", "dataset_titles": "Carbon chemistry from CTD; Deployment: NBP1302; NBP1302 data; Video Particle Profiler (VPP) and Digital Inline Holographic Microscopy (DIHM) data from cruise NBP1302", "datasets": [{"dataset_uid": "600388", "doi": "10.15784/600388", "keywords": "Antarctica; Biota; Holographic Microscopy; Oceans; Photo/video; Photo/Video; Phytoplankton; Ross Sea; Sample/collection Description; Sample/Collection Description; Southern Ocean; Video Particle Profiler", "people": "Bochdansky, Alexander", "repository": "USAP-DC", "science_program": null, "title": "Video Particle Profiler (VPP) and Digital Inline Holographic Microscopy (DIHM) data from cruise NBP1302", "url": "https://www.usap-dc.org/view/dataset/600388"}, {"dataset_uid": "000220", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Carbon chemistry from CTD", "url": "http://www.bco-dmo.org/dataset/658394"}, {"dataset_uid": "000179", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1302 data", "url": "https://www.rvdata.us/search/cruise/NBP1302"}, {"dataset_uid": "000221", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Deployment: NBP1302", "url": "http://www.bco-dmo.org/deployment/547873"}], "date_created": "Wed, 26 Aug 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eSinking particles are a major element of the biological pump and they are commonly assigned to two fates: mineralization in the water column and accumulation at the seafloor. However, there is another fate of export hidden within the vertical decline of carbon, the transformation of sinking organic matter to fine suspended and/or dissolved organic fractions. This process has been suggested but has rarely been observed or quantified. As a result, it is presumed that the solubilized fraction is largely mineralized over short time scales. However, global ocean surveys of dissolved organic carbon are demonstrating a significant water column accumulation of organic matter under high productivity environments. This proposal will investigate the transformation of organic particles from sinking to solubilized phases of the export flux in the Ross Sea. The Ross Sea experiences high export particle production, low dissolved organic carbon export with overturning circulation, and the area has a predictable succession of production and export events. In addition, the basin is shallow (\u003c 000 m) so the products the PIs will target are relatively concentrated. To address the proposed hypothesis, the PIs will use both well-established and novel biochemical and optical measures of export production and its fate. The outcomes of this work will help researchers close the carbon budget in the Ross Sea.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis research will support graduate and undergraduate students and will provide undergraduates and pre-college students with field-based research experience. Scientifically, this research will increase understanding of carbon sinks in the Ross Sea and will help develop new tools for identifying, quantifying, and tracking that carbon. The PIs will interface with K-12 students through daily reports from the field and through educational modules developed by several of the PIs in collaboration with science education specialists and college students. A K-12 educator will be included on the research cruises. Outreach will be through COSEE Florida and the Maritime Center in Norfolk, VA.", "east": 175.0, "geometry": "POINT(170 -65.25)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e DIHM; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "Not provided; NBP1302; Phaeocystis; R/V NBP", "locations": null, "north": -52.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Bochdansky, Alexander; Dunbar, Robert; DiTullio, Giacomo; Ditullio, Giacomo; Harry, Dennis L.; HANSELL, DENNIS", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "BCO-DMO; R2R; USAP-DC", "science_programs": null, "south": -78.5, "title": "Collaborative research: TRacing the fate of Algal Carbon Export in the Ross Sea (TRACERS)", "uid": "p0000307", "west": 165.0}, {"awards": "0944254 Smith, Walker; 0944165 McGillicuddy, Dennis", "bounds_geometry": "POLYGON((168 -65,168.2 -65,168.4 -65,168.6 -65,168.8 -65,169 -65,169.2 -65,169.4 -65,169.6 -65,169.8 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,169.8 -65,169.6 -65,169.4 -65,169.2 -65,169 -65,168.8 -65,168.6 -65,168.4 -65,168.2 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65))", "dataset_titles": "Data from expdition NBP1201; Expedition Data; Project data: Processes Regulating Iron Supply at the Mesoscale - Ross Sea", "datasets": [{"dataset_uid": "000155", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Project data: Processes Regulating Iron Supply at the Mesoscale - Ross Sea", "url": "http://www.bco-dmo.org/project/2155"}, {"dataset_uid": "001442", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1201"}, {"dataset_uid": "000156", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Data from expdition NBP1201", "url": "http://www.bco-dmo.org/deployment/506350"}], "date_created": "Wed, 08 Jul 2015 00:00:00 GMT", "description": "The Ross Sea continental shelf is one of the most productive areas in the Southern Ocean, and may comprise a significant, but unaccounted for, oceanic CO2 sink, largely driven by phytoplankton production. The processes that control the magnitude of primary production in this region are not well understood, but data suggest that iron limitation is a factor. Field observations and model simulations indicate four potential sources of dissolved iron to surface waters of the Ross Sea: (1) circumpolar deep water intruding from the shelf edge; (2) sediments on shallow banks and nearshore areas; (3) melting sea ice around the perimeter of the polynya; and (4) glacial meltwater from the Ross Ice Shelf. The principal investigators hypothesize that hydrodynamic transport via mesoscale currents, fronts, and eddies facilitate the supply of dissolved iron from these four sources to the surface waters of the Ross Sea polynya. These hypotheses will be tested through a combination of in situ observations and numerical modeling, complemented by satellite remote sensing. In situ observations will be obtained during a month-long cruise in the austral summer. The field data will be incorporated into model simulations, which allow quantification of the relative contributions of the various hypothesized iron supply mechanisms, and assessment of their impact on primary production. The research will provide new insights and a mechanistic understanding of the complex oceanographic phenomena that regulate iron supply, primary production, and biogeochemical cycling. The research will thus form the basis for predictions about how this system may change in a warming climate. The broader impacts include training of graduate and undergraduate students, international collaboration, and partnership with several ongoing outreach programs that address scientific research in the Southern Ocean. The research also will contribute to the goals of the international research programs ICED (Integrated Climate and Ecosystem Dynamics) and GEOTRACES (Biogeochemical cycling and trace elements in the marine environment).", "east": 170.0, "geometry": "POINT(169 -65)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "R/V NBP; Not provided", "locations": null, "north": -65.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker; McGillicuddy, Dennis", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "BCO-DMO", "repositories": "BCO-DMO; R2R", "science_programs": null, "south": -65.0, "title": "Collaborative Research: Impact of Mesoscale Processes on Iron Supply and Phytoplankton Dynamics in the Ross Sea", "uid": "p0000330", "west": 168.0}, {"awards": "1141890 Huber, Bruce", "bounds_geometry": "POLYGON((-62.176502 -57.913998,-61.4764715 -57.913998,-60.776441 -57.913998,-60.0764105 -57.913998,-59.37638 -57.913998,-58.6763495 -57.913998,-57.976319 -57.913998,-57.2762885 -57.913998,-56.576258 -57.913998,-55.8762275 -57.913998,-55.176197 -57.913998,-55.176197 -58.6469082,-55.176197 -59.3798184,-55.176197 -60.1127286,-55.176197 -60.8456388,-55.176197 -61.578549,-55.176197 -62.3114592,-55.176197 -63.0443694,-55.176197 -63.7772796,-55.176197 -64.5101898,-55.176197 -65.2431,-55.8762275 -65.2431,-56.576258 -65.2431,-57.2762885 -65.2431,-57.976319 -65.2431,-58.6763495 -65.2431,-59.37638 -65.2431,-60.0764105 -65.2431,-60.776441 -65.2431,-61.4764715 -65.2431,-62.176502 -65.2431,-62.176502 -64.5101898,-62.176502 -63.7772796,-62.176502 -63.0443694,-62.176502 -62.3114592,-62.176502 -61.578549,-62.176502 -60.8456388,-62.176502 -60.1127286,-62.176502 -59.3798184,-62.176502 -58.6469082,-62.176502 -57.913998))", "dataset_titles": "Expedition Data of NBP1203; Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203; Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "datasets": [{"dataset_uid": "001438", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1203", "url": "https://www.rvdata.us/search/cruise/NBP1203"}, {"dataset_uid": "601347", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Current Measurements; LADCP; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601347"}, {"dataset_uid": "601348", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": null, "title": "Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601348"}], "date_created": "Wed, 17 Jun 2015 00:00:00 GMT", "description": "Time series data, from ocean moorings, on key aspects of evolving ocean properties are of considerable importance in assessing the condition of the ocean system. They are needed, for example, their understand how the oceans are warming, and how they continue to uptake greenhouse gases such as CO2. \u003cbr/\u003e\u003cbr/\u003eThe Cape Adare Long Term Mooring (CALM) program goal was to observe the bottom water export from the Ross Sea to the deep ocean. To accomplish this two instrumented moorings were set on the continental slope off Cape Adare (western Ross Sea, Antarctica), positioned to capture the export of Antarctic Bottom Water (AABW), some of the coldest and densest water found in the global ocean. Data records for the moorings spans over some four years in this very remote part of the ocean. The CALM analysis will address some specific objectives:\u003cbr/\u003e? Characterize the temperature, salinity and current variability associated with the Ross Sea AABW export.\u003cbr/\u003e? Examine the linkages between observed variability to regional tides, atmosphere and sea ice forcing.\u003cbr/\u003e? Relate the Ross Sea AABW export fluctuations to the larger scale climate system dynamics, such as ENSO and SAM, and to AABW formation along other margins of Antarctica, e.g. the Weddell Sea", "east": -55.176197, "geometry": "POINT(-58.6763495 -61.578549)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -57.913998, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Huber, Bruce; Vernet, Maria", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -65.2431, "title": "Cape Adare Long Term Moorings (CALM): Analysis Phase", "uid": "p0000495", "west": -62.176502}, {"awards": "1332492 Lohmann, Rainer", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Origin of Persistent Organic Pollutants in the Antarctic Atmosphere, Snow and Marine Food Web", "datasets": [{"dataset_uid": "600138", "doi": "10.15784/600138", "keywords": "Animal Tracking; Antarctica; Antarctic Peninsula; Atmosphere; Biota; Chemistry:fluid; Chemistry:Fluid; Human Dimensions; McMurdo Sound; Oceans; Palmer Station; Pollution; Ross Sea; Sample/collection Description; Sample/Collection Description; Seals; Southern Ocean; Weddell Sea", "people": "Lohmann, Rainer", "repository": "USAP-DC", "science_program": null, "title": "Origin of Persistent Organic Pollutants in the Antarctic Atmosphere, Snow and Marine Food Web", "url": "https://www.usap-dc.org/view/dataset/600138"}], "date_created": "Tue, 09 Jun 2015 00:00:00 GMT", "description": "Many persistent organic pollutants (POPs), though banned in the U.S. since the 1970s, remain in the environment and continue to reach hitherto pristine regions such as the Arctic and Antarctic. The overall goals of this RAPID project are to better understand the remobilization of POPs from melting glaciers in the Antarctic, and their transfer into the food-web. Legacy POPs have characteristic chemical signatures that will be used ascertain the origin of POPs in the Antarctic atmosphere and marine food-web. Samples that were collected in 2010 will be analyzed for a wide range of legacy POPs, and their behavior will be contrasted with results for emerging contaminants. The intellectual merit of the proposed research combines (a) the use of chemical signatures to assess whether melting glaciers are releasing legacy POPs back into the Antarctic marine ecosystem, and (b) a better understanding of the food-web dynamics of legacy POPs versus emerging organic pollutants.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of the proposed research project will include the training of the next generation of scientists through support for a graduate student and a postdoctoral scholar. As well, this work will result in a better understanding of the relationship between pollutants, trophic food web ecology and global climate change in the pristine Antarctic ecosystem.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Lohmann, Rainer", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "RAPID: Origin of Persistent Organic Pollutants in the Antarctic Atmosphere, Snow and Marine Food WEB", "uid": "p0000344", "west": -180.0}, {"awards": "1321782 Costa, Daniel", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Retrospective Analysis of Antarctic Tracking data (RAATD): International Crabeater and Weddell Seal Tracking Data Sets", "datasets": [{"dataset_uid": "600137", "doi": "10.15784/600137", "keywords": "Animal Tracking; Antarctica; Biota; Oceans; Sample/collection Description; Sample/Collection Description; Seals; Southern Ocean", "people": "Costa, Daniel", "repository": "USAP-DC", "science_program": null, "title": "Retrospective Analysis of Antarctic Tracking data (RAATD): International Crabeater and Weddell Seal Tracking Data Sets", "url": "https://www.usap-dc.org/view/dataset/600137"}], "date_created": "Wed, 03 Jun 2015 00:00:00 GMT", "description": "Identifying the basic habitat requirements of Antarctic predators is fundamental to understanding how they will respond to the human-induced challenges of commercial fisheries and climate change. This understanding can only be achieved if the underlying linkages to physical processes are related to animal movements. As part of the international Retrospective Analysis of Antarctic Tracking Data (RAATD) organized by the SCAR Expert Group of Birds and Marine Mammals, this research will collate and synthesize tracking data from crabeater seals, Lobodon carcinophagus, and Weddell seals, Leptonychotes weddelli. These data will be combined with all available data from the Southern Ocean that has been collected by researchers from Norway, United Kingdom, Germany, Australia and the USA. These data will be analyzed using a common analytical approach and synthesized into a synoptic view of these two species across the Southern Ocean. The diving and movement patterns will be examined for each species. As well, the total home range and core habitat utilization patterns for each species and region will be determined. This study will develop global habitat maps for each species based on physical and biological attributes of their \"hot-spots\" and then overlay all the species specific maps to identify multi-species areas of ecological significance. Broader impacts include support and training for a postdoctoral scholar, the production of a publicly available database and the participation in an international data synthesis effort.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Costa, Daniel", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Retrospective Analysis of Antarctic Tracking data (RAATD): International Crabeater and Weddell Seal Tracking Data Sets", "uid": "p0000346", "west": -180.0}, {"awards": "1303896 Kirschvink, Joseph", "bounds_geometry": "POLYGON((-57 -63,-56.9 -63,-56.8 -63,-56.7 -63,-56.6 -63,-56.5 -63,-56.4 -63,-56.3 -63,-56.2 -63,-56.1 -63,-56 -63,-56 -63.2,-56 -63.4,-56 -63.6,-56 -63.8,-56 -64,-56 -64.2,-56 -64.4,-56 -64.6,-56 -64.8,-56 -65,-56.1 -65,-56.2 -65,-56.3 -65,-56.4 -65,-56.5 -65,-56.6 -65,-56.7 -65,-56.8 -65,-56.9 -65,-57 -65,-57 -64.8,-57 -64.6,-57 -64.4,-57 -64.2,-57 -64,-57 -63.8,-57 -63.6,-57 -63.4,-57 -63.2,-57 -63))", "dataset_titles": "Magnetostratigraphy of Cretaceous Sediments in the James Ross Island Basin, Antarctica", "datasets": [{"dataset_uid": "600136", "doi": "10.15784/600136", "keywords": "Antarctica; GPS; James Ross Basin; Sample/collection Description; Sample/Collection Description; Solid Earth", "people": "Kirschvink, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Magnetostratigraphy of Cretaceous Sediments in the James Ross Island Basin, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600136"}], "date_created": "Sat, 23 May 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PI will collect samples to extend the magneto-stratigraphic record of late Cretaceous sediments of the James Ross Basin, Antarctica. RAPID support will allow him to take advantage of an invitation from the Instituto Antartico Argentino (IAA) to participate on an excursion to James Ross Island in the Antarctic Peninsula. The PI hopes to collect samples that will refine the position of several geomagnetic reversals between the end of the Cretaceous long normal Chron and the lower portion of Chron 31R. The Brandy Bay locality targeted by this expedition is the best place in the basin for calibrating the biostratigraphic position of the top of the Cretaceous Long Normal Chron, which is one of the most reliable correlation horizons in the entire Geological Time Scale.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe top of the Cretaceous long normal Chron is not properly correlated to southern hemisphere biostratigraphy. Locating this event will be a major addition to understanding geological time. This expedition will provide opportunities for an undergraduate student. This project is based on a productive collaboration with an Argentine scientist.", "east": -56.0, "geometry": "POINT(-56.5 -64)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -63.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kirschvink, Joseph", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Magnetostratigraphy of Cretaceous Sediments in the James Ross Island Basin, Antarctica", "uid": "p0000419", "west": -57.0}, {"awards": "1043217 Zagorodnov, Victor", "bounds_geometry": null, "dataset_titles": "Fiber-Optic Distributed Temperature Sensing at Windless Bight", "datasets": [{"dataset_uid": "609604", "doi": "10.7265/N5V122QS", "keywords": "Antarctica; Ice Shelf; McMurdo Sound; Mooring; Oceans; Physical Oceanography; Ross Ice Shelf; Southern Ocean", "people": "Zagorodnov, Victor; Holland, David; Tyler, Scott W.", "repository": "USAP-DC", "science_program": null, "title": "Fiber-Optic Distributed Temperature Sensing at Windless Bight", "url": "https://www.usap-dc.org/view/dataset/609604"}], "date_created": "Tue, 05 May 2015 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eResearchers will explore the use of a distributed temperature sensing monitoring system (DTS), using fiber-optical (FO) technology, as the basis of a sustainable, sub-ice cavity sensing array. FO cable systems, such as may be deployed through a hot-water drilled hole through an ice shelf, passing through the underlying cavity to the sea floor, are capable of measuring temperatures down fiber at 1 meter intervals, and at time frequencies as high as 15 seconds. DTS FO systems operate via optical time domain reflectometry along the fiber waveguide using inelastic backscatter of coherent laser light as a probe beam in the FO environment.\u003cbr/\u003e\u003cbr/\u003eThe introduction of new technologies to the harsh environmental conditions of the Antarctic are often associated with high risk. However, the potential rewards of this approach (e.g. multiyear capability, minimal submerged mechanical or electrical components that may fail, relative simplicity of deployment and measurement principle, yet yielding distributed real time and spatial observation) are attractive enough to conduct a pilot project at a field-ready location (McMurdo). \u003cbr/\u003e\u003cbr/\u003eCurrent indications are that the instability of some of the world\u0027s largest ice sheets located around the Antarctic and Greenland may be caused by the presence of warming, deep ocean waters, shoaling over continental shelves, and melting the underside of floating ice shelves. Additional knowledge of the temporal and spatial variability of the temperature fields underneath terminal ice shelves, such as those draining the West Antarctic Ice Sheet, are needed to accurately project future global climate effects on ice-shelf ocean interactions, and in order to inform societal and technological aspects of adaption to changing sea-level.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e TEMPERATURE LOGGERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS", "is_usap_dc": true, "keywords": "GROUND STATIONS; Not provided; Conservative Temperature; MOORINGS; Ice Shelf Temperature; Ocean Temperature", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Zagorodnov, Victor; Holland, David; Tyler, Scott W.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED \u003e MOORINGS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Application of Distributed Temperature Sensors (DTS) for Antarctic Ice Shelves and Cavities", "uid": "p0000183", "west": null}, {"awards": "1146554 Rack, Frank", "bounds_geometry": "POLYGON((153.694 -77.89028,155.025433 -77.89028,156.356866 -77.89028,157.688299 -77.89028,159.019732 -77.89028,160.351165 -77.89028,161.682598 -77.89028,163.014031 -77.89028,164.345464 -77.89028,165.676897 -77.89028,167.00833 -77.89028,167.00833 -78.525252,167.00833 -79.160224,167.00833 -79.795196,167.00833 -80.430168,167.00833 -81.06514,167.00833 -81.700112,167.00833 -82.335084,167.00833 -82.970056,167.00833 -83.605028,167.00833 -84.24,165.676897 -84.24,164.345464 -84.24,163.014031 -84.24,161.682598 -84.24,160.351165 -84.24,159.019732 -84.24,157.688299 -84.24,156.356866 -84.24,155.025433 -84.24,153.694 -84.24,153.694 -83.605028,153.694 -82.970056,153.694 -82.335084,153.694 -81.700112,153.694 -81.06514,153.694 -80.430168,153.694 -79.795196,153.694 -79.160224,153.694 -78.525252,153.694 -77.89028))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 27 Apr 2015 00:00:00 GMT", "description": "This award provides support for \"EAGER: Handbook of Hot Water Drill System (HWDS) Design Considerations and Best Practices\" from the Antarctic Integrated System Science within the Office of Polar Programs. More and more science projects are proposing to use hot-water drilling systems (HWDS) to rapidly and/or cleanly access glacial and subglacial systems. To date the hot-water drill systems have been developed in isolation, and no attempt has been made to gather information about the different systems in one place. This proposal requests funds to document existing HWDS, and to then assess the design, testing, and development of a hot-water drill system that will be integrated with the evolving over-ice traverse capability of the USAP program.\u003cbr/\u003e\u003cbr/\u003eIntellectual Merit: A working handbook of best practices for hot-water drill design systems, including safety considerations, is long overdue, and will 1) provide suggestions for optimizing current systems; 2) contribute in the very near term to already funded projects such as WISSARD (Whillans Ice Stream Subglacial Access and Research Drilling); and 3) fit the long-term needs of the Antarctic science community who have identified rapid and clean access to glacial and subglaical environments as a top priority for the next decades. The collected information will be used for community education and training, will discuss potential design and operational trade-offs, and will identify ways to optimize the capabilities of an integrated USAP traverse and HWDS infrastructure. EAGER funding for this project is warranted because such a handbook has not been tried before, and needs to be shown to be doable prior to larger investments in such compilations. It fits the AISS (Antarctic Integrated System Science) program as an optimized HWDS will meet the needs of many different Antarctic research disciplines including biology, geology, glaciology, and oceanography.\u003cbr/\u003e\u003cbr/\u003eBroader Impacts: The proposed work is being done on behalf of the Antarctic research community, and will seek to capture the knowledge of experienced hot-water drill engineers who are nearing retirement, and to educate the next generation of hot-water drillers and engineers. The PI indicates he will work with the owners of such systems both within the US and abroad. Identification of best practices in hot-water drilling will save several different Antarctic research communities significant time, effort, and funding in the future.", "east": 167.00833, "geometry": "POINT(160.351165 -81.06514)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e GRAVITY CORER; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE TRANSDUCERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e NISKIN BOTTLES; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e FSI; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS", "is_usap_dc": false, "keywords": "Hot Water Drill; Subglacial Lake; Ross Ice Shelf; West Antarctic Ice Sheet; FIELD SURVEYS; TRAVERSE; Clean Access Drilling; Drilling Parameters; FIELD INVESTIGATION; DRILLING PLATFORMS; Not provided; Antarctica; WISSARD; Whillans Ice Stream; FIXED OBSERVATION STATIONS", "locations": "Antarctica; West Antarctic Ice Sheet; Whillans Ice Stream; Ross Ice Shelf", "north": -77.89028, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Rack, Frank", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e FIXED OBSERVATION STATIONS; LAND-BASED PLATFORMS \u003e VEHICLES \u003e TRAVERSE; Not provided; WATER-BASED PLATFORMS \u003e FIXED PLATFORMS \u003e SURFACE \u003e DRILLING PLATFORMS", "repositories": null, "science_programs": null, "south": -84.24, "title": "EAGER: Handbook of Hot Water Drill System (HWDS) Design Considerations and Best Practices.", "uid": "p0000729", "west": 153.694}, {"awards": "0229314 Stone, John", "bounds_geometry": null, "dataset_titles": "Reedy Glacier Exposure Ages, Antarctica", "datasets": [{"dataset_uid": "609601", "doi": "10.7265/N5MG7MF1", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Cosmogenic; Geochemistry; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Reedy Glacier; Sample/collection Description; Sample/Collection Description", "people": "Stone, John", "repository": "USAP-DC", "science_program": null, "title": "Reedy Glacier Exposure Ages, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609601"}], "date_created": "Mon, 30 Mar 2015 00:00:00 GMT", "description": "The stability of the marine West Antarctic Ice Sheet (WAIS) remains an important, unresolved problem for predicting future sea level change. Recent studies indicate that the mass balance of the ice sheet today may be negative or positive. The apparent differences may stem in part from short-term fluctuations in flow. By comparison, geologic observations provide evidence of behavior over much longer time scales. Recent work involving glacial-geologic mapping, dating and ice-penetrating radar surveys suggests that deglaciation of both the Ross Sea Embayment and coastal Marie Byrd Land continued into the late Holocene, and leaves open the possibility of ongoing deglaciation and grounding-line retreat. However, previous work in the Ross Sea Embayment was based on data from just three locations that are all far to the north of the present grounding line. Additional data from farther south in the Ross Sea Embayment are needed to investigate whether recession has ended, or if the rate and pattern of deglaciation inferred from our previous study still apply to the present grounding line. This award provides support to reconstruct the evolution of Reedy Glacier, in the southern Transantarctic Mountains, since the Last Glacial Maximum (LGM). Because Reedy Glacier emerges from the mountains above the grounding line, its surface slope and elevation should record changes in thickness of grounded ice in the Ross Sea up to the present day. The deglaciation chronology of Reedy Glacier therefore can indicate whether Holocene retreat of the WAIS ended thousands of years ago, or is still continuing at present. This integrated glaciologic, glacial-geologic, and cosmogenic-isotope exposure- dating project will reconstruct past levels of Reedy Glacier. Over two field seasons, moraines will be mapped, dated and correlated at sites along the length of the glacier. Radar and GPS measurements will be made to supplement existing ice thickness and velocity data, which are needed as input for a model of glacier dynamics. The model will be used to relate geologic measurements to the grounding-line position downstream. Ultimately, the mapping, dating and ice-modeling components of the study will be integrated into a reconstruction that defines changes in ice thickness in the southern Ross Sea since the LGM, and relates these changes to the history of grounding-line retreat. This work directly addresses key goals of the West Antarctic Ice Sheet Initiative, which are to understand the dynamics, recent history and possible future behavior of the West Antarctic Ice Sheet.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "Surface Exposure Dates; FIELD SURVEYS; Aluminum-26; Erosion; Rock Samples; Beryllium-10; Exposure Age", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Stone, John", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Late Quaternary History of Reedy Glacier", "uid": "p0000029", "west": null}, {"awards": "0944556 Barrett, John", "bounds_geometry": "POLYGON((160.6015 -76.9089,161.7382 -76.9089,162.8749 -76.9089,164.0116 -76.9089,165.1483 -76.9089,166.285 -76.9089,167.4217 -76.9089,168.5584 -76.9089,169.6951 -76.9089,170.8318 -76.9089,171.9685 -76.9089,171.9685 -77.73527,171.9685 -78.56164,171.9685 -79.38801,171.9685 -80.21438,171.9685 -81.04075,171.9685 -81.86712,171.9685 -82.69349,171.9685 -83.51986,171.9685 -84.34623,171.9685 -85.1726,170.8318 -85.1726,169.6951 -85.1726,168.5584 -85.1726,167.4217 -85.1726,166.285 -85.1726,165.1483 -85.1726,164.0116 -85.1726,162.8749 -85.1726,161.7382 -85.1726,160.6015 -85.1726,160.6015 -84.34623,160.6015 -83.51986,160.6015 -82.69349,160.6015 -81.86712,160.6015 -81.04075,160.6015 -80.21438,160.6015 -79.38801,160.6015 -78.56164,160.6015 -77.73527,160.6015 -76.9089))", "dataset_titles": "Ecosphere (Supplement), Ecological Society of America.", "datasets": [{"dataset_uid": "002538", "doi": "", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Ecosphere (Supplement), Ecological Society of America.", "url": "http://www.esapubs.org/archive/ecos/C004/014/suppl-1.php"}], "date_created": "Fri, 13 Feb 2015 00:00:00 GMT", "description": "Advances in molecular techniques have expanded our understanding of soil microbial communities, and raised important questions about regional and global patterns in microbial diversity. The proposed research will investigate the composition and activity of microbial communities across a range of geochemical and hydrologic soil conditions, and over local to regional scales in the Transantarctic Mountains, in order to assess controls over microbial biogeography. The research targets two areas in the Transantarctic mountains, the McMurdo Dry Valleys, and the Beardmore Glacier region further south, the latter representing an underexplored and inarguably more extreme soil environment. The research project will adopt an integrated approach, using molecular techniques and in situ assessment of biological activity in a quantitative biogeographical framework, with the goal of distinguishing fine versus broad scale controls over microbial community structure. The research is essential to determining the basic trophic status of extreme microbial food webs, and their sensitivity to climate change. The investigators will engage secondary and post-secondary educators through first person outreach as well as web-based communications and exercises. Two postdoctoral scientists will be trained in an interdisciplinary and international setting.", "east": 171.9685, "geometry": "POINT(166.285 -81.04075)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.9089, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Barrett, John", "platforms": "Not provided", "repo": "Publication", "repositories": "Publication", "science_programs": null, "south": -85.1726, "title": "Collaborative Research: Controls over the Spatial Distribution and Activity of Microbial Communities in Antarctic Soils", "uid": "p0000350", "west": 160.6015}, {"awards": "0944645 Goodge, John", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 11 Feb 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eBecause of extensive ice cover and sparse remote-sensing data, the geology of the Precambrian East Antarctic Shield (EAS) remains largely unexplored with information limited to coastal outcrops from the African, Indian and Australian sectors. The East Antarctic lithosphere is globally important: as one of the largest coherent Precambrian shields, including rocks as old as ~3.8 Ga, it played an important role in global crustal growth; it is a key piece in assembly of the Rodinia and Gondwana supercontinents; it is the substrate to Earth?s major ice cap, including numerous sub-glacial lakes, and influences its thermal state and mechanical stability; and its geotectonic association with formerly adjacent continental blocks in South Africa, India and Australia suggest that it might harbor important mineral resources. This project will increase understanding of the age and composition of the western EAS lithosphere underlying and adjacent to the Transantarctic Mountains (TAM) using U-Pb ages, and Hf- and O-isotope analysis of zircon in early Paleozoic granitoids and Pleistocene glacial tills. TAM granites of the early Paleozoic Ross Orogen represent an areally extensive continental-margin arc suite that can provide direct information about the EAS crust from which it melted and/or through which it passed. Large rock clasts of igneous and metamorphic lithologies entrained in glacial tills at the head of major outlet glaciers traversing the TAM provide eroded samples of the proximal EAS basement. Zircons in these materials will provide data about age and inheritance (U-Pb), crustal vs. mantle origin (O isotopes), and crustal sources and evolution (Hf isotopes). Integrated along a significant part of the TAM, these data will help define broader crustal provinces that can be correlated with geophysical data and used to test models of crustal assembly. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis project will provide a research opportunity for undergraduate and graduate students. Undergraduates will be involved as Research Assistants in sample preparation, imaging, and analytical procedures, and conducting their own independent research. The two main elements of this project will form the basis of MS thesis projects for two graduate students at UMD. Through this project they will gain a good understanding of petrology, isotope geochemistry, and analytical methods. The broader scientific impacts of this work are that it will help develop a better understanding of the origin and evolution of East Antarctic lithosphere underlying and adjacent to the TAM, which will be of value to the broader earth science and glaciological community. Furthermore, knowledge of East Antarctic geology is of continuing interest to the general public because of strong curiosity about past supercontinents, what?s under the ice, and the impact of global warming on ice-sheet stability.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Transantarctic Mountains; Not provided", "locations": "Transantarctic Mountains", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Goodge, John", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Age and Composition of the East Antarctic Shield by Isotopic Analysis of Granite and Glacial Till", "uid": "p0000258", "west": null}, {"awards": "0944557 Marsh, Adam", "bounds_geometry": "POINT(166 78)", "dataset_titles": "Environmental Genomics of an Antarctic Polychaete #SRP040946", "datasets": [{"dataset_uid": "000223", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Environmental Genomics of an Antarctic Polychaete #SRP040946", "url": "https://www.ncbi.nlm.nih.gov/sra/?term=SRP040946"}], "date_created": "Tue, 13 Jan 2015 00:00:00 GMT", "description": "Genome-enabled biology provides a foundation for understanding the genetic basis of organism-environment interactions. . The research project links gene expression, genome methylation, and metabolic rates to assess the mechanisms of environmental adaptation (temperature) across multiple generations in a polar, and closely related temperate, polychaete. By comparing these two species, the research will assess how a polar environment shapes responses to environmental stress. This work will produce: 1) a database of full transcriptome (gene specific) profiling data for the polar polychaete cultured at two temperatures; 2) the contribution of genome methylation to the suppression of gene transcription activities; 3) the linkage between shifts in mRNA pools and total cellular activities (as ATP consumption via respiration); 4) an assessment of the inheritance of patterns of gene expression and metabolic activities across three generations; and 5) a simple demographic model of the polar polychaete population dynamics under normal and \u0027global-warming\u0027 temperature scenarios. Broader impacts include two outreach activities. The first is a mentoring program, where African-American undergraduate students spend 1.5 years working on a research project with a UD faculty member (2 summers plus their senior academic year). The second is a children\u0027s display activity at UD?s School of Marine Science \"Coast Day\".", "east": 166.0, "geometry": "POINT(166 -78)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -78.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Marsh, Adam G.", "platforms": "Not provided", "repo": "NCBI GenBank", "repositories": "NCBI GenBank", "science_programs": null, "south": -78.0, "title": "Environmental Genomics in an Antarctic polychaete", "uid": "p0000355", "west": 166.0}, {"awards": "0732730 Truffer, Martin; 0732804 McPhee, Miles; 0732869 Holland, David; 0732906 Nowicki, Sophie", "bounds_geometry": "POINT(-100.728 -75.0427)", "dataset_titles": "Automatic Weather Station Pine Island Glacier; Borehole Temperatures at Pine Island Glacier, Antarctica; Ocean-Ice Interaction in the Amundsen Sea Sector of West Antarctica", "datasets": [{"dataset_uid": "609627", "doi": "10.7265/N5T151MV", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Pine Island Glacier; Temperature", "people": "Truffer, Martin; Stanton, Timothy", "repository": "USAP-DC", "science_program": null, "title": "Borehole Temperatures at Pine Island Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609627"}, {"dataset_uid": "601216", "doi": "10.15784/601216", "keywords": "Antarctica; Atmosphere; Automated Weather Station; Flux; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Meteorology; Pine Island Glacier; Weather Station Data", "people": "Mojica Moncada, Jhon F.; Holland, David", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Automatic Weather Station Pine Island Glacier", "url": "https://www.usap-dc.org/view/dataset/601216"}, {"dataset_uid": "600072", "doi": "10.15784/600072", "keywords": "Antarctica; Atmosphere; McMurdo; Meteorology; Oceans; Ross Island; Southern Ocean", "people": "McPhee, Miles G.", "repository": "USAP-DC", "science_program": null, "title": "Ocean-Ice Interaction in the Amundsen Sea Sector of West Antarctica", "url": "https://www.usap-dc.org/view/dataset/600072"}], "date_created": "Tue, 30 Dec 2014 00:00:00 GMT", "description": "Collaborative With: McPhee 0732804, Holland 0732869, Truffer 0732730, Stanton 0732926, Anandakrishnan 0732844 \u003cbr/\u003eTitle: Collaborative Research: IPY: Ocean-Ice Interaction in the Amundsen Sea Sector of West Antarctica\u003cbr/\u003e\u003cbr/\u003eThe Office of Polar Programs, Antarctic Integrated and System Science Program has made this award to support an interdisciplinary study of the effects of the ocean on the stability of glacial ice in the most dynamic region the West Antarctic Ice Sheet, namely the Pine Island Glacier in the Amundsen Sea Embayment. The collaborative project builds on the knowledge gained by the highly successful West Antarctic Ice Sheet program and is being jointly sponsored with NASA. Recent observations indicate a significant ice loss, equivalent to 10% of the ongoing increase in sea-level rise, in this region. These changes are largest along the coast and propagate rapidly inland, indicating the critical impact of the ocean on ice sheet stability in the region. While a broad range of remote sensing and ground-based instrumentation is available to characterize changes of the ice surface and internal structure (deformation, ice motion, melt) and the shape of the underlying sediment and rock bed, instrumentation has yet to be successfully deployed for observing boundary layer processes of the ocean cavity which underlies the floating ice shelf and where rapid melting is apparently occurring. Innovative, mini ocean sensors that can be lowered through boreholes in the ice shelf (about 500 m thick) will be developed and deployed to automatically provide ocean profiling information over at least three years. Their data will be transmitted through a conducting cable frozen in the borehole to the surface where it will be further transmitted via satellite to a laboratory in the US. Geophysical and remote sensing methods (seismic, GPS, altimetry, stereo imaging, radar profiling) will be applied to map the geometry of the ice shelf, the shape of the sub ice-shelf cavity, the ice surface geometry and deformations within the glacial ice. To integrate the seismic, glaciological and oceanographic observations, a new 3-dimensional coupled ice-ocean model is being developed which will be the first of its kind. NASA is supporting satellite based research and the deployment of a robotic-camera system to explore the environment in the ocean cavity underlying the ice shelf and NSF is supporting all other aspects of this study. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: This project is motivated by the potential societal impacts of rapid sea level rise and should result in critically needed improvements in characterizing and predicting the behavior of coupled ocean-ice systems. It is a contribution to the International Polar Year and was endorsed by the International Council for Science as a component of the \"Multidisciplinary Study of the Amundsen Sea Embayment\" proposal #258 of the honeycomb of endorsed IPY activities. The research involves substantial international partnerships with the British Antarctic Survey and the University of Bristol in the UK. The investigators will partner with the previously funded \"Polar Palooza\" education and outreach program in addition to undertaking a diverse set of outreach activities of their own. Eight graduate students and one undergraduate as well as one post doc will be integrated into this research project.", "east": -100.728, "geometry": "POINT(-100.728 -75.0427)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e SEISMIC REFLECTION PROFILERS", "is_usap_dc": true, "keywords": "West Antarctica; Seismic; LABORATORY; Amundsen Sea; Ocean-Ice Interaction; Remote Sensing; COMPUTERS; FIELD SURVEYS; LANDSAT-8; FIELD INVESTIGATION; Ocean Profiling; AUVS; Sea Level Rise; Stability; Not provided; Deformation; SATELLITES; Ice Movement; GROUND-BASED OBSERVATIONS; Ice Temperature; International Polar Year; Borehole", "locations": "West Antarctica; Amundsen Sea", "north": -75.0427, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Truffer, Martin; Stanton, Timothy; Bindschadler, Robert; Behar, Alberto; Nowicki, Sophie; Anandakrishnan, Sridhar; Holland, David; McPhee, Miles G.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e LANDSAT \u003e LANDSAT-8; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SATELLITES; WATER-BASED PLATFORMS \u003e UNCREWED VEHICLES \u003e SUBSURFACE \u003e AUVS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -75.0427, "title": "Collaborative Research; IPY: Ocean-Ice Interaction in the Amundsen Sea sector of West Antarctica", "uid": "p0000043", "west": -100.728}, {"awards": "0944220 Ponganis, Paul", "bounds_geometry": "POLYGON((-180 -68,-147 -68,-114 -68,-81 -68,-48 -68,-15 -68,18 -68,51 -68,84 -68,117 -68,150 -68,150 -69,150 -70,150 -71,150 -72,150 -73,150 -74,150 -75,150 -76,150 -77,150 -78,117 -78,84 -78,51 -78,18 -78,-15 -78,-48 -78,-81 -78,-114 -78,-147 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -77,160 -76,160 -75,160 -74,160 -73,160 -72,160 -71,160 -70,160 -69,160 -68,162 -68,164 -68,166 -68,168 -68,170 -68,172 -68,174 -68,176 -68,178 -68,-180 -68))", "dataset_titles": "The Physiological Ecology of Two Antarctic Icons: Emperor Penguins and Leopard Seals", "datasets": [{"dataset_uid": "600113", "doi": "10.15784/600113", "keywords": "Antarctica; Biota; Electrocardiogram; Penguin; Southern Ocean", "people": "Ponganis, Paul", "repository": "USAP-DC", "science_program": null, "title": "The Physiological Ecology of Two Antarctic Icons: Emperor Penguins and Leopard Seals", "url": "https://www.usap-dc.org/view/dataset/600113"}], "date_created": "Mon, 24 Nov 2014 00:00:00 GMT", "description": "Emperor penguins (Aptenodytes forsteri) and leopard seals (Hydrurga leptonyx) are iconic, top predators in Antarctica. Understanding their physiological ecology is essential to the assessment of their adaptability to the threats of climate change, pollution, and overfishing. The proposed research has multipronged objectives. Prior results suggest that Emperor penguins have flexible (vs. static) aerobic dive limits (ADL) that vary with the type of dive, and that the role of heart rate in utilization of oxygen stores also varies with dive type. A series of physiological measurements are proposed with backpack electrocardiogram recorders, that will allow further delineation of patterns and interrelationships among heart rate, dive behavior, and oxygen stores. Importantly, the research will be done on free diving emperors, and not individuals confined to a dive hole, thereby providing a more genuine measure of diving physiology and behavior. A separate objective is to examine foraging behavior of leopard seals, using a backpack digital camera and time depth recorder. Leopard seal behavior and prey intake is poorly quantified, but known to be significant. Accordingly the research is somewhat exploratory but will provide important baseline data. Finally, the P.I. proposes to continue long term overflight censuses of Emperor penguin colonies in the Ross Sea. Broader impacts include collaboration with National Geographic television, graduate student training, and development of sedation techniques for leopard seals.", "east": 150.0, "geometry": "POINT(-25 -73)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -68.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ponganis, Paul", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "The Physiological Ecology of Two Antarctic Icons: Emperor Penguins and Leopard Seals", "uid": "p0000349", "west": 160.0}, {"awards": "0943935 Isbell, John; 0943934 Taylor, Edith", "bounds_geometry": null, "dataset_titles": "Portal to search geologic sample collections, Polar Rock Repository, Byrd Polar Research Center, The Ohio State University; Portal to search paleobotanical collections, Biodiversity Institute, University of Kansas", "datasets": [{"dataset_uid": "002567", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Portal to search paleobotanical collections, Biodiversity Institute, University of Kansas", "url": "http://biodiversity.ku.edu/paleobotany/collections/collections-search"}, {"dataset_uid": "001377", "doi": "", "keywords": null, "people": null, "repository": "PRR", "science_program": null, "title": "Portal to search geologic sample collections, Polar Rock Repository, Byrd Polar Research Center, The Ohio State University", "url": "http://research.bpcrc.osu.edu/rr/"}, {"dataset_uid": "001402", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Portal to search paleobotanical collections, Biodiversity Institute, University of Kansas", "url": "http://biodiversity.ku.edu/paleobotany/collections/collections-search"}], "date_created": "Tue, 23 Sep 2014 00:00:00 GMT", "description": "Intellectual Merit:\u003cbr/\u003eThe focus of this proposal is to collect fossil plants and palynomorphs from Permian-Triassic (P-T) rocks of the central Transantarctic Mountains (CTM), together with detailed data on sedimentologic and paleoecologic depositional environments. Fossil plants are important climate proxies that offer a unique window into the past, and the CTM fossils are an important source of data on the ways that plants responded to a strongly seasonal, polar light regime during a time of global change. The proposed project uses paleobotanical expertise, integrated with detailed sedimentology and stratigraphy, to reconstruct Permian-Triassic plant communities and their paleoenvironments. This interdisciplinary approach could uncover details of Antarctica?s complex late Paleozoic and Mesozoic environmental and climatic history which included: 1) deglaciation, 2) development and evolution of a post-glacial landscape and biota, 3) environmental and biotic change associated with the end-Permian mass extinction, 4) environmental recovery in the earliest Triassic, 5) strong, possible runaway Triassic greenhouse, and 6) widespread orogenesis and development of a foreland basin system. The PIs will collect compression floras both quantitatively and qualitatively to obtain biodiversity and abundance data. Since silicified wood is also present, the PIs will analyze tree rings and growth in a warm, high-latitude environment for which there is no modern analogue. Fossil plants from the CTM can provide biological and environmental information to: 1) interpret paleoclimate when Gondwana moved from icehouse to greenhouse conditions; 2) trace floral evolution across the P-T boundary; 3) reconstruct Antarctic plant life; 4) further understanding of plant adaptations to high latitudes. The Intellectual Merit of the research includes: 1) tracing floral evolution after the retreat of glaciers; 2) examining floral composition and diversity across the PTB; and 3) obtaining data on the recovery of these ecosystems in the Early Triassic, as well as changes in floral cover and diversity in the Early-Middle Triassic. Antarctica is the only place on Earth that includes extensive outcrops of terrestrial rocks, combined with widespread and well-preserved plant fossils, which spans this crucial time period.\u003cbr/\u003e\u003cbr/\u003eBroader impacts:\u003cbr/\u003eThe broader impacts include public outreach; teaching, and mentoring of women and underrepresented students; mentoring graduate student, postdoctoral, and new faculty women; development of an inquiry-based workshop on Antarctic paleoclimate with the Division of Education, KU Natural History Museum; continuing support of workshops for middle school girls in science via the Expanding Your Horizons Program, Emporia State University, and the TRIO program, KU; exploring Antarctic geosciences through video/computer links from McMurdo Station and satellite phone conferences from the field with K-12 science classes in Wisconsin and Kansas, and through participation in the NSF Research Experiences for Teachers program at the University of Wisconsin.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "FIELD SURVEYS; LABORATORY; Transanatarctic Basin; Paleobotany; Fossil Plants; FIELD INVESTIGATION; Sedimentology; Late Paleozoic Ice Age; Not provided; Central Transantarctic Mountains; Beardmore Glacier", "locations": "Transanatarctic Basin; Central Transantarctic Mountains; Beardmore Glacier", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Instrumentation and Support; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e PALEOZOIC \u003e PERMIAN; PHANEROZOIC \u003e MESOZOIC \u003e TRIASSIC; PHANEROZOIC \u003e PALEOZOIC \u003e PERMIAN; PHANEROZOIC \u003e MESOZOIC \u003e TRIASSIC", "persons": "Isbell, John", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "PI website", "repositories": "PI website; PRR", "science_programs": null, "south": null, "title": "Collaborative Research: Antarctic Ecosystems across the Permian-Triassic Boundary: Integrating Paleobotany, Sedimentology, and Paleoecology", "uid": "p0000372", "west": null}, {"awards": "1043700 Harry, Dennis", "bounds_geometry": "POLYGON((-180 -70,-176.5 -70,-173 -70,-169.5 -70,-166 -70,-162.5 -70,-159 -70,-155.5 -70,-152 -70,-148.5 -70,-145 -70,-145 -71,-145 -72,-145 -73,-145 -74,-145 -75,-145 -76,-145 -77,-145 -78,-145 -79,-145 -80,-148.5 -80,-152 -80,-155.5 -80,-159 -80,-162.5 -80,-166 -80,-169.5 -80,-173 -80,-176.5 -80,180 -80,177.5 -80,175 -80,172.5 -80,170 -80,167.5 -80,165 -80,162.5 -80,160 -80,157.5 -80,155 -80,155 -79,155 -78,155 -77,155 -76,155 -75,155 -74,155 -73,155 -72,155 -71,155 -70,157.5 -70,160 -70,162.5 -70,165 -70,167.5 -70,170 -70,172.5 -70,175 -70,177.5 -70,-180 -70))", "dataset_titles": "Geodynamic Models of Subsidence and Lithospheric Flexure at the ANDRILL Drill Sites: Implications for Cenozoic Tectonics and Ice Sheet History; Ross Sea post-middle Miocene seismic interpretation", "datasets": [{"dataset_uid": "601227", "doi": "10.15784/601227", "keywords": "Andrill; Antarctica; Marine Geoscience; Ross Sea; Seismic Interpretation; Seismic Reflection; Stratigraphy; Subsidence; Victoria Land Basin", "people": "Harry, Dennis L.", "repository": "USAP-DC", "science_program": "ANDRILL", "title": "Ross Sea post-middle Miocene seismic interpretation", "url": "https://www.usap-dc.org/view/dataset/601227"}, {"dataset_uid": "600128", "doi": "10.15784/600128", "keywords": "Andrill; Antarctica; Continental Rift; Geology/Geophysics - Other; Lithosphere; Model; Ross Sea; Solid Earth; Tectonic; Transantarctic Mountains", "people": "Harry, Dennis L.", "repository": "USAP-DC", "science_program": "ANDRILL", "title": "Geodynamic Models of Subsidence and Lithospheric Flexure at the ANDRILL Drill Sites: Implications for Cenozoic Tectonics and Ice Sheet History", "url": "https://www.usap-dc.org/view/dataset/600128"}], "date_created": "Sun, 31 Aug 2014 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThis research will place the subsidence history of the southern Victoria Land Basin into a quantitative geodynamic context and will assess the influence of flexure associated with late Neogene volcanic loading of the crust by the Erebus Volcanic Group. This will be done by extending geodynamic models of extension in the West Antarctic Rift System to include extensional hiatuses hypothesized to have occurred during the Late Paleogene and Miocene, and by developing a new geodynamic model of volcanic loading and associated lithosphere flexure. Finite element and finite difference modeling methods will be used. In the first phase of the project, a series of extensional geodynamic models will be developed to examine the effect that proposed extensional hiatuses have on the style of extension, with emphasis placed on developing a process based understanding of the change in rift style from diffuse during the Late Cretaceous to more focused during the Cenozoic. The models will test the hypotheses that extensional hiatuses led to the change in rifting style, and will place constraints on the timing and duration of the hiatuses. The second phase of the project will use the thermal and rheological properties of the previous models to constrain the flexural rigidity of the lithosphere in order to model the flexural response to volcanic loading to test the hypotheses that flexural subsidence contributed to cyclic changes between grounded and floating ice at the ANDRILL AND-1A site, complicating interpretations of the climatic record from this core, and that flexure contributes to the stress orientation at the AND-2B site, which is inconsistent with the expected regional extensional stress orientation.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe project will train an undergraduate student and an M.S. student. Outreach activities include a planned series of talks at regional high schools, junior colleges, and 4-year colleges that have geology programs.", "east": -145.0, "geometry": "POINT(-175 -75)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; MARINE GEOPHYSICS; Antarctica; NOT APPLICABLE", "locations": "Antarctica", "north": -70.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Harry, Dennis L.", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -80.0, "title": "Geodynamic Models of Subsidence and Lithospheric Flexure at the ANDRILL Drill Sites: Implications for Cenozoic Tectonics and Ice Sheet History", "uid": "p0000467", "west": 155.0}, {"awards": "0087345 Conway, Howard", "bounds_geometry": "POINT(112 79)", "dataset_titles": null, "datasets": null, "date_created": "Fri, 15 Aug 2014 00:00:00 GMT", "description": "This award supports a program of ground-based geophysical measurements to map in detail the spatial variations of ice flow, accumulation rate, internal layering and ice thickness at the sites which have been identified as promising locations to drill the next deep ice core in West Antarctica. The main investigative tools are a high- and low-frequency ice penetrating radar to image the topography of internal layers and the bed, repeat GPS surveys to calculate the present day surface velocity field, synthetic aperture radar (SAR) interferometry to calculate the regional velocity field, and short firn cores to calculate present day accumulation rates. The data which will be collected will be used to as input to time-dependent ice flow and temperature models that will predict depth variation of age, layer thickness, and temperature. As well as yielding an estimate of expected conditions before drilling, the mismatch between the model prediction and data eventually recovered from the core will help infer thinning and climate (accumulation and temperature) histories for the region. The Western Divide, between the Ross Sea Embayment and the Amundsen Sea, has been identified as the region which best satisfies the criteria which have been established for a deep drilling site. Preliminary site selection using airborne geophysical methods has identified several potential drill sites on the Western Divide where the climate record should be best preserved. This work will contribute in a major way to the final site selection for the next deep ice core in West Antarctica.", "east": -112.0, "geometry": "POINT(-112 -79)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e SAR", "is_usap_dc": false, "keywords": "FIELD SURVEYS; Internal Layering; Radar; Accumulation Rate; FIELD INVESTIGATION; LABORATORY; Not provided; Internal Layers; Antarctica; Ice Flow; Interferometry; Ice Thickness", "locations": "Antarctica", "north": -79.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard; Waddington, Edwin D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -79.0, "title": "Collaborative Research: Western Divide West Antarctic Ice Cores (WAISCORES) Site Selection", "uid": "p0000557", "west": -112.0}, {"awards": "0944489 Williams, Trevor", "bounds_geometry": "POLYGON((-55 -58,-33.2 -58,-11.4 -58,10.4 -58,32.2 -58,54 -58,75.8 -58,97.6 -58,119.4 -58,141.2 -58,163 -58,163 -60,163 -62,163 -64,163 -66,163 -68,163 -70,163 -72,163 -74,163 -76,163 -78,141.2 -78,119.4 -78,97.6 -78,75.8 -78,54 -78,32.2 -78,10.4 -78,-11.4 -78,-33.2 -78,-55 -78,-55 -76,-55 -74,-55 -72,-55 -70,-55 -68,-55 -66,-55 -64,-55 -62,-55 -60,-55 -58))", "dataset_titles": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris", "datasets": [{"dataset_uid": "600116", "doi": "10.15784/600116", "keywords": "Geochronology; George V Land; IODP U1356; IODP U1361; Marine Sediments; ODP1165; Prydz Bay; Solid Earth; Southern Ocean; Wilkes Land", "people": "Hemming, Sidney R.; Williams, Trevor", "repository": "USAP-DC", "science_program": null, "title": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris", "url": "https://www.usap-dc.org/view/dataset/600116"}], "date_created": "Wed, 13 Aug 2014 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to study the stability and dynamics of the East Antarctic ice sheet during the Pliocene in the area of the Wilkes and Aurora subglacial basins. Models indicate the ice sheet is most sensitive to warming in these low-lying areas. This study is important as there is very little direct evidence about which parts of the East Antarctic ice sheet became unstable under warm conditions. In a pilot study the PIs have shown that the isotopic geochemical signature of downcore ice-rafted debris (IRD) can be linked to continental source areas indicating which parts of the ice sheet reached the coast and calved IRD-bearing icebergs. Their initial results suggest rapid iceberg discharge from the Wilkes Land and Ad\u00e9lie Land coastal areas at times in the late Miocene and early Pliocene. In this study the PIs will analyze IRD from IODP sediment cores collected on the continental rise off East Antarctica. By analyzing 40Ar/39Ar ages of hornblende IRD grains, U-Pb ages of zircons, and Sm-Nd isotopes of the fine fraction of several IRD-rich layers for each core, they will be able to fingerprint continental source areas that will indicated ice extent and dynamics on East Antarctica. The PIs will also carry out detailed studies across a few of these layers to characterize the anatomy of the ice-rafting event and better understand the mechanism of ice destabilization.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe data collected will be important for scientists in a broad variety of fields. The project will involve one undergraduate student and one summer intern at LDEO, and a graduate student at Imperial College London. The project will expose to cutting edge methodologies as well as an international research team. Data from the project will be deposited in the online databases (SedDB) and all results and methods will be made available to the scientific community through publications in peer-reviewed journals and attendance at international conferences.", "east": 163.0, "geometry": "POINT(54 -68)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -58.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Williams, Trevor; Hemming, Sidney R.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris", "uid": "p0000353", "west": -55.0}, {"awards": "1043265 Deming, Jody", "bounds_geometry": "POLYGON((162.1397 -77.14085,162.828507 -77.14085,163.517314 -77.14085,164.206121 -77.14085,164.894928 -77.14085,165.583735 -77.14085,166.272542 -77.14085,166.961349 -77.14085,167.650156 -77.14085,168.338963 -77.14085,169.02777 -77.14085,169.02777 -77.200745,169.02777 -77.26064,169.02777 -77.320535,169.02777 -77.38043,169.02777 -77.440325,169.02777 -77.50022,169.02777 -77.560115,169.02777 -77.62001,169.02777 -77.679905,169.02777 -77.7398,168.338963 -77.7398,167.650156 -77.7398,166.961349 -77.7398,166.272542 -77.7398,165.583735 -77.7398,164.894928 -77.7398,164.206121 -77.7398,163.517314 -77.7398,162.828507 -77.7398,162.1397 -77.7398,162.1397 -77.679905,162.1397 -77.62001,162.1397 -77.560115,162.1397 -77.50022,162.1397 -77.440325,162.1397 -77.38043,162.1397 -77.320535,162.1397 -77.26064,162.1397 -77.200745,162.1397 -77.14085))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 31 Jul 2014 00:00:00 GMT", "description": "The relatively pristine Antarctic continent with its extensive maritime zone represents a unique location on the planet to investigate the long distance aerial transport and deposition of marine microorganisms. The vast extent of new sea ice that forms each winter around the continent results in large numbers of frost flowers, delicate ice-crystal structures of high salt content that form on the surface of the ice and are readily dispersed by wind. The proposed research builds on earlier work in the Arctic and tests the new hypothesis that wind-borne frost flowers provide an effective mechanism for the transport of marine bacteria over long distances, one that can be uniquely sourced and tracked by the frost flower salt signature in the Antarctic realm. A highly resolved genomic snapshot of the microbial community will be acquired at each stage in the transport path, which will track decreasing fractions of the marine microbial community as it freezes into sea ice, incorporates into frost flowers, converts to aerosols, and ultimately deposits within continental snowpack. En route from sea ice to snowpack, marine bacteria will be exposed to an array of environmental stresses, including high salinity, low temperatures, UV light and potential desiccation. A parallel proteomic analysis will enable an evaluation of the microbial response to these extreme conditions and potential survival mechanisms that allow persistence or eventual colonization of deposition sites across Antarctica. \u003cbr/\u003e\u003cbr/\u003eCurrent understanding of microbes in the Antarctic atmosphere is based on a limited number of microscopic and culture-based assays and a single report of low-resolution 16S RNA gene sequence analysis. The research will broadly impact understanding of atmospheric microbiology, from source to deposition, and various issues of microbial survival, colonization, endemism, and diversity under extreme conditions. In addition to venues that reach the scientific community, the research team will develop a permanent multi-media and artifact-based exhibit on Antarctic Microbial Transport that will be showcased at Seattle\u0027s Pacific Science Center (PSC), which educates nearly a million visitors annually.", "east": 169.02777, "geometry": "POINT(165.583735 -77.440325)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.14085, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Deming, Jody", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.7398, "title": "High Resolution Genomic and Proteomic Analyses of a Microbial Transport Mechanism from Antarctic Marine Waters to Permanent Snowpack", "uid": "p0000356", "west": 162.1397}, {"awards": "0944475 Kaplan, Michael", "bounds_geometry": "POLYGON((-149.7 -84.1,-118.61 -84.1,-87.52 -84.1,-56.43 -84.1,-25.34 -84.1,5.75 -84.1,36.84 -84.1,67.93 -84.1,99.02 -84.1,130.11 -84.1,161.2 -84.1,161.2 -84.43,161.2 -84.76,161.2 -85.09,161.2 -85.42,161.2 -85.75,161.2 -86.08,161.2 -86.41,161.2 -86.74,161.2 -87.07,161.2 -87.4,130.11 -87.4,99.02 -87.4,67.93 -87.4,36.84 -87.4,5.75 -87.4,-25.34 -87.4,-56.43 -87.4,-87.52 -87.4,-118.61 -87.4,-149.7 -87.4,-149.7 -87.07,-149.7 -86.74,-149.7 -86.41,-149.7 -86.08,-149.7 -85.75,-149.7 -85.42,-149.7 -85.09,-149.7 -84.76,-149.7 -84.43,-149.7 -84.1))", "dataset_titles": "Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "datasets": [{"dataset_uid": "600115", "doi": "10.15784/600115", "keywords": "Antarctica; Cosmogenic Dating; Sample/collection Description; Sample/Collection Description; Solid Earth; Transantarctic Mountains", "people": "Kaplan, Michael", "repository": "USAP-DC", "science_program": null, "title": "Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "url": "https://www.usap-dc.org/view/dataset/600115"}], "date_created": "Thu, 17 Jul 2014 00:00:00 GMT", "description": "The proposed work will investigate changes in the compositional variation of glacial tills over time across two concentric sequences of Pleistocene moraines located adjacent to the heads of East Antarctic outlet glaciers in the Transantarctic Mountains (TAM). The chronologic framework for this work will be generated from cosmogenic exposure ages of boulders on prominent morainal ridges. The PIs hypothesize that variations in till composition may indicate a change in ice flow direction or a change in the composition of the original source area, while ages of the moraines provide a long-term terrestrial perspective on ice sheet dynamics. Both results are vital for modeling experiments that aim to reconstruct the East Antarctic Ice Sheet and assess its role in the global climate system and its potential impact on global sea level rise. The variation of till compositions through time also allows for a more accurate interpretation of sediment cores from the Ross Sea and the Southern Ocean. Additionally, till exposures at the head of some East Antarctic outlet glaciers have been shown to contain subglacial material derived from East Antarctic bedrock, providing a window through the ice to view East Antarctica?s inaccessible bedrock. Till samples will be collected from two well-preserved sequences of moraine crests at Mt. Howe (head of Scott Glacier) and Mt. Achernar (between Beardmore and Nimrod Glaciers). Each size fraction in glacial till provides potentially valuable information, and the PIs will measure the petrography of the clast and sand fractions, quantitative X-ray diffraction on the crushed \u003c2mm fraction, elemental abundance of the silt/clay fraction, and U/Pb of detrital zircons in the sand fraction. Data collection will rely on established methods previously used in this region and the PIs will also explore new methods to assess their efficacy. On the same moraines crests sampled for provenance studies, the PIs will sample for cosmogenic surface exposure analyses to provide a chronologic framework at the sites for provenance changes through time. \u003cbr/\u003e\u003cbr/\u003eBroader Impact \u003cbr/\u003eThe proposed research involves graduate and undergraduate training in a diverse array of laboratory methods. Students and PIs will be make presentations to community and campus groups, as well as conduct interviews with local news outlets. The proposed work also establishes a new, potentially long-term, collaboration between scientists at IUPUI and LDEO and brings a new PI (Kaplan) into the field of Antarctic Earth Sciences.", "east": 161.2, "geometry": "POINT(5.75 -85.75)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION", "locations": null, "north": -84.1, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kaplan, Michael", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.4, "title": "Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "uid": "p0000459", "west": -149.7}, {"awards": "1045215 Gooseff, Michael", "bounds_geometry": "POLYGON((160 -77.25,160.5 -77.25,161 -77.25,161.5 -77.25,162 -77.25,162.5 -77.25,163 -77.25,163.5 -77.25,164 -77.25,164.5 -77.25,165 -77.25,165 -77.375,165 -77.5,165 -77.625,165 -77.75,165 -77.875,165 -78,165 -78.125,165 -78.25,165 -78.375,165 -78.5,164.5 -78.5,164 -78.5,163.5 -78.5,163 -78.5,162.5 -78.5,162 -78.5,161.5 -78.5,161 -78.5,160.5 -78.5,160 -78.5,160 -78.375,160 -78.25,160 -78.125,160 -78,160 -77.875,160 -77.75,160 -77.625,160 -77.5,160 -77.375,160 -77.25))", "dataset_titles": "Are the Dry Valleys Getting Wetter? A Preliminary Assessment of Wetness Across the McMurdo Dry Valleys Landscape", "datasets": [{"dataset_uid": "600131", "doi": "10.15784/600131", "keywords": "Antarctica; Climate; Critical Zone; Dry Valleys; Radar; Soil Moisture", "people": "Gooseff, Michael N.", "repository": "USAP-DC", "science_program": null, "title": "Are the Dry Valleys Getting Wetter? A Preliminary Assessment of Wetness Across the McMurdo Dry Valleys Landscape", "url": "https://www.usap-dc.org/view/dataset/600131"}], "date_created": "Tue, 01 Jul 2014 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eUntil recently, wetted soils in the Dry Valleys were generally only found adjacent to streams and lakes. Since the warm austral summer of 2002, numerous ?wet spots? have been observed far from shorelines on relatively flat valley floor locations and as downslope fingers of flow on valley walls. The source of the water to wet these soils is unclear, as is the spatial and temporal pattern of occurrence from year to year. Their significance is potentially great as enhanced soil moisture may change the thermodynamics, hydrology, and erosion rate of surface soils, and facilitate transport of materials that had previously been stable. These changes to the soil active layer could significantly modify permafrost and ground ice stability within the Dry Valleys. The PIs seek to investigate these changes to address two competing hypotheses: that the source of water to these ?wet spots? is ground ice melt and that the source of this water is snowmelt. The PIs will document the spatiotemporal dynamics of these wet areas using high frequency remote sensing data from Quickbird and Wordview satellites to document the occurrence, dimensions, and growth of wet spots during the 2010-\u00c2\u00ad11 and 2011-\u00c2\u00ad12 austral summers. They will test their hypotheses by determining whether wet spots recur in the same locations in each season, and they will compare present to past distribution using archived imagery. They will also determine whether spatial snow accumulation patterns and temporal ablation patterns are coincident with wet spot formation. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eOne graduate student will be trained on this project. Findings will be reported at scientific meetings and published in peer reviewed journals. They will also develop a teaching module on remote sensing applications to hydrology for the Modular Curriculum for Hydrologic Advancement and an innovative prototype project designed to leverage public participation in mapping wet spots and snow patches across the Dry Valleys through the use of social media and mobile computing applications.", "east": 165.0, "geometry": "POINT(162.5 -77.875)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; AMD; USAP-DC; ANALYTICAL LAB; Amd/Us", "locations": null, "north": -77.25, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Gooseff, Michael N.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.5, "title": "EAGER: Are the Dry Valleys Getting Wetter? A Preliminary Assessment of Wetness Across the McMurdo Dry Valleys Landscape", "uid": "p0000471", "west": 160.0}, {"awards": "1250208 Friedlaender, Ari", "bounds_geometry": "POLYGON((-80 -63,-78 -63,-76 -63,-74 -63,-72 -63,-70 -63,-68 -63,-66 -63,-64 -63,-62 -63,-60 -63,-60 -63.7,-60 -64.4,-60 -65.1,-60 -65.8,-60 -66.5,-60 -67.2,-60 -67.9,-60 -68.6,-60 -69.3,-60 -70,-62 -70,-64 -70,-66 -70,-68 -70,-70 -70,-72 -70,-74 -70,-76 -70,-78 -70,-80 -70,-80 -69.3,-80 -68.6,-80 -67.9,-80 -67.2,-80 -66.5,-80 -65.8,-80 -65.1,-80 -64.4,-80 -63.7,-80 -63))", "dataset_titles": "Linking the Movement Patterns and Foraging Behavior of Humpback Whales to their Prey across Multiple Spatial Scales within the LTER Study Region", "datasets": [{"dataset_uid": "600151", "doi": "10.15784/600151", "keywords": "Antarctica; Antarctic Peninsula; Biota; Oceans; Sample/collection Description; Sample/Collection Description; Southern Ocean; Whales", "people": "Johnston, David; Friedlaender, Ari; Nowacek, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Linking the Movement Patterns and Foraging Behavior of Humpback Whales to their Prey across Multiple Spatial Scales within the LTER Study Region", "url": "https://www.usap-dc.org/view/dataset/600151"}], "date_created": "Mon, 10 Mar 2014 00:00:00 GMT", "description": "Whales play a central role in the ecology and biogeochemistry of the Southern Ocean. However, little is known regarding their distribution and behavior, in part because of challenges associated with studying these organisms from large research vessels. This research will take advantage of the unique opportunity presented by the 2012-2013 test run of the smaller, more mobile R/V Point Sur. This work will use the Point Sur to investigate humpback whales in the waters studied by the Palmer Long Term Ecological Research (LTER) Station off the Western Antarctic Peninsula (WAP). Employing a combination of long-term satellite-linked tags and short-term suction cup tags, researchers will investigate the distribution, abundance and foraging behaviors of whales in this region. Whale biogeography will then be related to quantitative surveys of krill, their primary food source. Hypotheses regarding whale distribution and foraging strategies as well as physical oceanographic features will be tested. The WAP is undergoing some of the most dramatic warming on the planet, and a better understanding of the ecology of top predators is central to developing an understanding of the impacts of this change. Results will be widely disseminated through publications as well as through presentations at national and international meetings. In addition, raw data will be made available through open-access databases. Finally, this work will be coordinated with the extensive infrastructure of the Palmer LTER site, enabling outreach and educational activities.", "east": -60.0, "geometry": "POINT(-70 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Friedlaender, Ari; Nowacek, Douglas; Johnston, David", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LTER", "south": -70.0, "title": "RAPID: Linking the Movement Patterns and Foraging Behavior of Humpback Whales to their Prey across Multiple Spatial Scales within the LTER Study Region", "uid": "p0000666", "west": -80.0}, {"awards": "1043619 Hemming, Sidney; 1043572 Licht, Kathy", "bounds_geometry": "POLYGON((-177.982 -63.997,-149.64107 -63.997,-121.30014 -63.997,-92.95921 -63.997,-64.61828 -63.997,-36.27735 -63.997,-7.93642 -63.997,20.40451 -63.997,48.74544 -63.997,77.08637 -63.997,105.4273 -63.997,105.4273 -66.3324,105.4273 -68.6678,105.4273 -71.0032,105.4273 -73.3386,105.4273 -75.674,105.4273 -78.0094,105.4273 -80.3448,105.4273 -82.6802,105.4273 -85.0156,105.4273 -87.351,77.08637 -87.351,48.74544 -87.351,20.40451 -87.351,-7.93642 -87.351,-36.27735 -87.351,-64.61828 -87.351,-92.95921 -87.351,-121.30014 -87.351,-149.64107 -87.351,-177.982 -87.351,-177.982 -85.0156,-177.982 -82.6802,-177.982 -80.3448,-177.982 -78.0094,-177.982 -75.674,-177.982 -73.3386,-177.982 -71.0032,-177.982 -68.6678,-177.982 -66.3324,-177.982 -63.997))", "dataset_titles": "East Antarctic outlet glacier contributions to the Ross Sea from chronology of detrital grains", "datasets": [{"dataset_uid": "600124", "doi": "10.15784/600124", "keywords": "Antarctica; East Antarctica; Geochemistry; Ross Sea; Sample/collection Description; Sample/Collection Description; Solid Earth; Southern Ocean; West Antarctica", "people": "Hemming, Sidney R.", "repository": "USAP-DC", "science_program": null, "title": "East Antarctic outlet glacier contributions to the Ross Sea from chronology of detrital grains", "url": "https://www.usap-dc.org/view/dataset/600124"}], "date_created": "Tue, 18 Feb 2014 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs proposed a provenance study of glacial deposits in the Ross Embayment that will provide a broad scale geochronologic survey of detrital minerals in till to help characterize bedrock beneath the East Antarctic ice sheet and constrain Antarctica?s glacial history. This project capitalizes on previous investments in field sampling. Analytical tools applied to single mineral grains extracted from existing collections of glacial till will generate ?fingerprints? of East Antarctic outlet glaciers and West Antarctic till to refine paleo-ice flow models for the Ross Embayment during the last glacial maximum, older records from ANDRILL cores, and to assess IRD sources in the Southern Ocean. New provenance tracers will include a suite of geochronological methods that together provide greater insights into the orogenic and erosional history the region. This project will include U/Pb of detrital zircons, (U-Th)/He on a subset of the U/Pb dated zircons, as well as Ar-Ar of detrital hornblende, mica and feldspars. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis research will train one M.S. student at IUPUI, a Ph.D. student at Columbia, and several undergraduates at both institutions. Graduate students involved in the project will be involved in mentoring undergraduate researchers. Incorporation of research discoveries will be brought into the classroom by providing concrete examples and exercises at the appropriate level. Licht and Columbia graduate student E. Pierce are developing outreach projects with local secondary school teachers to investigate the provenance of glacial materials in their local areas. The research will have broad applicability to many fields.", "east": 105.4273, "geometry": "POINT(-36.27735 -75.674)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e LA-ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e PETROGRAPHIC MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS", "is_usap_dc": true, "keywords": "Not provided; FIELD SURVEYS", "locations": null, "north": -63.997, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Licht, Kathy; Hemming, Sidney R.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.351, "title": "Collaborative Research: East Antarctic outlet glacier contributions to the Ross Sea from chronology of detrital grains", "uid": "p0000333", "west": -177.982}, {"awards": "1043745 Halanych, Kenneth", "bounds_geometry": null, "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001427", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1210"}, {"dataset_uid": "000439", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1312"}], "date_created": "Fri, 07 Feb 2014 00:00:00 GMT", "description": "The research will explore the genetics, diversity, and biogeography of Antarctic marine benthic invertebrates, seeking to overturn the widely accepted suggestion that benthic fauna do not constitute a large, panmictic population. The investigators will sample adults and larvae from undersampled regions of West Antarctica that, combined with existing samples, will provide significant coverage of the western hemisphere of the Southern Ocean. The objectives are: 1) To assess the degree of genetic connectivity (or isolation) of benthic invertebrate species in the Western Antarctic using high-resolution genetic markers. 2) To begin exploring planktonic larvae spatial and bathymetric distributions for benthic shelf invertebrates in the Bellinghausen, Amundsen and Ross Seas. 3) To continue to develop a Marine Antarctic Genetic Inventory (MAGI) that relates larval and adult forms via DNA barcoding. Broader impacts include traditional forms of training (postdocs, graduate studentships, undergraduate research experiences) and lectures to K-12 groups.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e PROFILERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES", "is_usap_dc": false, "keywords": "R/V LMG; R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Halanych, Kenneth", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Genetic connectivity and biogeographic patterns of Antarctic benthic invertebrates", "uid": "p0000263", "west": null}, {"awards": "1232962 Ledwell, James", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1310A", "datasets": [{"dataset_uid": "002658", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1310A", "url": "https://www.rvdata.us/search/cruise/NBP1310A"}], "date_created": "Fri, 07 Feb 2014 00:00:00 GMT", "description": "Intellectual Merit: The Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) is a study of ocean mixing in the Antarctic Circumpolar Current (ACC) which runs west to east all around the continent of Antarctica, south of the other continents. This current system is somewhat of a barrier to transport of heat, carbon dioxide and other important ocean constituents between the far south and the rest of the ocean, and mixing processes play an important role in those transports. DIMES is a multi-investigator cooperative project, led by physical oceanographers in the U.S. and in the U.K. A passive tracer and an array of sub-surface floats were deployed early in 2009 more than 2000 km west of Drake Passage on a surface of constant density about 1500 m deep between the Sub Antarctic Front and the Polar Front of the ACC. In early 2010 a U.S. led research cruise sampled the tracer, turbulence levels, and the velocity and density profiles that govern the generation of that turbulence, and additional U.K. led research cruises in 2011 and 2012 continue this sampling as the tracer has made its way through Drake Passage, into the Scotia Sea, and over the North Scotia Ridge, a track of more than 3000 km. The initial results show that diapycnal, i.e., vertical, mixing west of Drake Passage where the bottom is relatively smooth is no larger than in most other regions of the open ocean. In contrast, there are strong velocity shears and intense turbulence levels over the rough topography in Drake Passage and diapycnal diffusivity of the tracer more than 10 times larger in Drake Passage and to the east than west of Drake Passage.\u003cbr/\u003e\u003cbr/\u003eThe DIMES field program continues with the U.S. team collecting new velocity and turbulence data in the Scotia Sea. It is anticipated that the tracer will continue passing through the Scotia Sea until at least early 2014. The U.K. partners have scheduled sampling of the tracer on cruises at the North Scotia Ridge and in the eastern and central Scotia Sea in early 2013 and early 2014. The current project will continue the time series of the tracer at Drake Passage on two more U.S. led cruises, in late 2012 and late 2013. Trajectories through the Scotia Sea estimated from the tracer observations, from neutrally buoyant floats, and from numerical models will be used to accurately estimate mixing rates of the tracer and to locate where the mixing is concentrated. During the 2013 cruise the velocity and turbulence fields along high-resolution transects along the ACC and across the ridges of Drake Passage will be measured to see how far downstream of the ridges the mixing is enhanced, and to test the hypothesis that mixing is enhanced by breaking lee waves generated by flow over the rough topography.\u003cbr/\u003e\u003cbr/\u003eBroader Impacts: DIMES (see web site at http://dimes.ucsd.edu) involves many graduate students and post-doctoral researchers. Two graduate students, who would become expert in ocean turbulence and the processes generating it, will continue be trained on this project. The work in DIMES is ultimately motivated by the need to understand the overturning circulation of the global ocean. This circulation governs the transport and storage of heat and carbon dioxide within the huge oceanic reservoir, and thus plays a major role in regulating the earth?s climate. Understanding the circulation and how it changes in reaction to external forces is necessary to the understanding of past climate change and of how climate might change in the future, and is therefore of great importance to human well-being. The data collected and analyzed by the DIMES project will be assembled and made publicly available at the end of the project.\u003cbr/\u003e\u003cbr/\u003eThe DIMES project is a process experiment sponsored by the U.S. CLIVAR (Climate variability and predictability) program.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Ledwell, James", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Studies of Turbulence and Mixing in the Antarctic Circumpolar Current, a Continuation of DIMES", "uid": "p0000846", "west": null}, {"awards": "1043740 Lenczewski, Melissa", "bounds_geometry": "POLYGON((165 -77.5,165.3 -77.5,165.6 -77.5,165.9 -77.5,166.2 -77.5,166.5 -77.5,166.8 -77.5,167.1 -77.5,167.4 -77.5,167.7 -77.5,168 -77.5,168 -77.6,168 -77.7,168 -77.8,168 -77.9,168 -78,168 -78.1,168 -78.2,168 -78.3,168 -78.4,168 -78.5,167.7 -78.5,167.4 -78.5,167.1 -78.5,166.8 -78.5,166.5 -78.5,166.2 -78.5,165.9 -78.5,165.6 -78.5,165.3 -78.5,165 -78.5,165 -78.4,165 -78.3,165 -78.2,165 -78.1,165 -78,165 -77.9,165 -77.8,165 -77.7,165 -77.6,165 -77.5))", "dataset_titles": "Fate of Drilling Fluids during the South McMurdo Sound Project (SMS) of the Antarctic Geological Drilling Program (ANDRILL)", "datasets": [{"dataset_uid": "600129", "doi": "10.15784/600129", "keywords": "Andrill; Antarctica; Chemistry:fluid; Chemistry:Fluid; Chemistry:rock; Chemistry:Rock; Drilling Fluid; Geochemistry; McMurdo; Ross Sea; Sediment Core", "people": "Lenczewski, Melissa", "repository": "USAP-DC", "science_program": "ANDRILL", "title": "Fate of Drilling Fluids during the South McMurdo Sound Project (SMS) of the Antarctic Geological Drilling Program (ANDRILL)", "url": "https://www.usap-dc.org/view/dataset/600129"}], "date_created": "Mon, 27 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PI proposes to utilize computer models used by hydrogeologists to establish the fate and transport of contamination and determine the extent of drilling fluid contamination in the ANDRILL SMS core. For these models, previously collected logs of lithology, porosity, fracture density, fracture type, fracture orientation, drilling fluid loss, drilling fluid characteristics and temperature will be used as input parameters. In addition, biodegradation and sorption constants for the drilling fluid will be determined and incorporated into the models. Samples of drilling fluids used during coring as well as the return fluids were collected at the drill site using standard microbiological sampling techniques. Fluids will be tested at in situ temperatures under aerobic and anaerobic conditions to determine biodegradation constants. Sorption will be determined between the drilling fluids and core samples using standard isotherm methods. Geochemical and microbial fingerprints of the fluids and the changes during biodegradation will determine the potential impact of the drilling fluids on the isolated microbial communities and the geochemistry within various subsurface lithologic units beneath the southern McMurdo Sound in Antarctica. The results of this study could potentially provide guidelines on developing less detrimental methods for future exploration, if deemed necessary through this research.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis proposed project will train a graduate student. The methods developed for analyses of samples in this project will serve as a guide for future studies of similar interest and will improve the understanding of ecological impacts of geologic drilling in Antarctica. The results of this study will be used as a reference for comparison with future studies examining newly developed, and improved, sample collection methods in future exploratory drilling projects in pristine environments. The PI is new to Antarctic research.", "east": 168.0, "geometry": "POINT(166.5 -78)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Lenczewski, Melissa", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -78.5, "title": "Fate of Drilling Fluids during the South McMurdo Sound Project (SMS) of the Antarctic Geological Drilling Program (ANDRILL)", "uid": "p0000468", "west": 165.0}, {"awards": "0739515 Fagan, William", "bounds_geometry": "POLYGON((-68.383 -60.65,-66.10137 -60.65,-63.81974 -60.65,-61.53811 -60.65,-59.25648 -60.65,-56.97485 -60.65,-54.69322 -60.65,-52.41159 -60.65,-50.12996 -60.65,-47.84833 -60.65,-45.5667 -60.65,-45.5667 -61.4145,-45.5667 -62.179,-45.5667 -62.9435,-45.5667 -63.708,-45.5667 -64.4725,-45.5667 -65.237,-45.5667 -66.0015,-45.5667 -66.766,-45.5667 -67.5305,-45.5667 -68.295,-47.84833 -68.295,-50.12996 -68.295,-52.41159 -68.295,-54.69322 -68.295,-56.97485 -68.295,-59.25648 -68.295,-61.53811 -68.295,-63.81974 -68.295,-66.10137 -68.295,-68.383 -68.295,-68.383 -67.5305,-68.383 -66.766,-68.383 -66.0015,-68.383 -65.237,-68.383 -64.4725,-68.383 -63.708,-68.383 -62.9435,-68.383 -62.179,-68.383 -61.4145,-68.383 -60.65))", "dataset_titles": "Data Paper, ESA Ecology", "datasets": [{"dataset_uid": "000141", "doi": "", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Data Paper, ESA Ecology", "url": "http://dx.doi.org/10.1890/13-1108.1"}], "date_created": "Fri, 17 Jan 2014 00:00:00 GMT", "description": "This five-year project seeks to characterize decadal scale changes in penguin and seabird populations on the Antarctic Peninsula, and to identify the factors driving these long-term changes. Two interconnected research activities are proposed: 1. Continued, long-term monitoring and censusing of penguin and seabird populations at \u003e117 sites throughout the Antarctic Peninsula via opportunistic ship-based data collection. 2. Synthesis and quantitative analyses of datasets detailing long-term changes in five penguin and seabird species from diverse sites throughout the Antarctic Peninsula. When complete, the penguin/seabird database will incorporate data from the Antarctic Site Inventory (ASI), the CCAMLR database, the US AMLR database, the LTER database from Palmer Station, data from British and Argentine researchers, historic census data compiled by the Scientific Committee on Antarctic Research (SCAR), and, when possible, additional privately held datasets. Additional data for temperature change, sea ice coverage, the seasonal timing and intensity of human visitation, and other factors have been gathered and will be analyzed together with population trajectories within a spatially explicit framework. The research will include hierarchical statistical analyses to characterize the long-term population dynamics of several key polar species across multiple spatial scales (sites, regions, and the Peninsula). Analyses also will focus on specific subsets of the overall database to contrast visitor impacts on paired colonies, sites, and regions that share similar environmental conditions but differ in the intensity of tourism. \u003cbr/\u003e\u003cbr/\u003eThe Broader Impacts include (1) research training and first-time Antarctic experiences for a postdoctoral researcher and several graduate students, all of whom will then be better positioned to bring their expertise in spatial and/or quantitative/theoretical ecology to bear on questions in polar research; (2) assembly and analysis of a large, multi-season database of penguin and seabird time series from the Antarctic Peninsula that will be publicly available, (3) assistance in distinguishing the impacts of tourism versus climate change on seabird populations. Under the Environmental Protocol to the Antarctic Treaty, Treaty Parties are charged with regular and effective monitoring to assess the impacts of human activities. This project will uniquely assist Parties in fulfilling this mandate.", "east": -45.5667, "geometry": "POINT(-56.97485 -64.4725)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.65, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Fagan, William; Lynch, Heather", "platforms": "Not provided", "repo": "Publication", "repositories": "Publication", "science_programs": null, "south": -68.295, "title": "Collaborative Research: Multispecies, Multiscale Investigations of Longterm Changes in Penguin and Seabird Populations on the Antarctic Peninsula", "uid": "p0000465", "west": -68.383}, {"awards": "0838850 Gooseff, Michael", "bounds_geometry": "POLYGON((162.32 -77.62,162.418 -77.62,162.516 -77.62,162.614 -77.62,162.712 -77.62,162.81 -77.62,162.90800000000002 -77.62,163.006 -77.62,163.104 -77.62,163.202 -77.62,163.3 -77.62,163.3 -77.631,163.3 -77.64200000000001,163.3 -77.653,163.3 -77.664,163.3 -77.67500000000001,163.3 -77.686,163.3 -77.697,163.3 -77.708,163.3 -77.71900000000001,163.3 -77.73,163.202 -77.73,163.104 -77.73,163.006 -77.73,162.90800000000002 -77.73,162.81 -77.73,162.712 -77.73,162.614 -77.73,162.516 -77.73,162.418 -77.73,162.32 -77.73,162.32 -77.71900000000001,162.32 -77.708,162.32 -77.697,162.32 -77.686,162.32 -77.67500000000001,162.32 -77.664,162.32 -77.653,162.32 -77.64200000000001,162.32 -77.631,162.32 -77.62))", "dataset_titles": "The Role of Snow Patches on the Spatial Distribution of Soil Microbial Communities and Biogeochemical Cycling in the Antarctic Dry Valleys", "datasets": [{"dataset_uid": "600100", "doi": "10.15784/600100", "keywords": "Antarctica; Critical Zone; Mps-1 Water Potential Sensor; Physical Properties; Soil Moisture; Soil Temperature", "people": "Gooseff, Michael N.", "repository": "USAP-DC", "science_program": null, "title": "The Role of Snow Patches on the Spatial Distribution of Soil Microbial Communities and Biogeochemical Cycling in the Antarctic Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/600100"}], "date_created": "Tue, 26 Nov 2013 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eTwo models have been proposed to describe controls over microbial biogeography. One model proposes that microbes are ubiquitously distributed across the global environment, and that environmental conditions select for taxa physiologically adapted to local physical conditions. An alternative model predicts that dispersal is the important limitation to the distribution of microorganisms and that spatial heterogeneity of microbial communities is a result of both dispersal and local environmental limitations. According to both models, spatial heterogeneity of microbial communities may be especially pronounced in extreme ecosystems where the environmental selection for organisms with suitable physiology is most strongly manifest. We propose that Antarctic terrestrial environments are ideal places to examine microbial biogeography for 3 reasons: 1) the pristine nature and remoteness of Antarctica minimizes the prevalence of exotic species dispersed through human vectors; 2) the extreme conditions of Antarctic environments provide a strong environmental filter which limits the establishment of non-indigenous taxa; and 3) extreme heterogeneity in the terrestrial environment provides natural gradients of soil conditions (temperature, water and nutrient availability). In the proposed research we will investigate the influence of snow on the composition and spatial distribution of soil microbial communities and linked biogeochemical cycling in the McMurdo Dry Valleys. We will conduct fieldwork at the landscape scale (repeated remote sensing to characterize snow distribution), at the valley and patch scales (quantify snow patch ablation, microbial communities and biogeochemical cycling in subnivian soils). We hypothesize that snow patches play an important role in structuring the spatial distribution of soil microbial communities and their associated ecosystem functioning because of the physical and hydrological influences that snow patches have on the soil environment. The research will contribute to greater public awareness of the importance of polar research to fundamental questions of biology, ecology and hydrology through direct linkages with International Antarctic Institute public outreach activities, including dissemination of web-based learning units on environmental science and microbiology, targeted as resources for secondary and post-secondary educators. Three graduate students, one postdoctoral scholar and multiple undergraduates will participate in the research activities.", "east": 163.3, "geometry": "POINT(162.81 -77.675)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.62, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gooseff, Michael N.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.73, "title": "Collaborative Research: The Role of Snow Patches on the Spatial Distribution of Soil Microbial Communities and Biogeochemical Cycling in the Antarctic Dry Valleys", "uid": "p0000489", "west": 162.32}, {"awards": "0838948 Hofmann, Eileen", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 14 Nov 2013 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eThe Ross Sea is a highly productive area within the Southern Ocean, but it experiences substantial variability in both physical (temperature, ice concentrations, salinity, winds, and current velocities) and biogeochemical (chlorophyll, productivity, micronutrients, higher trophic level standing stocks, gases, etc.) conditions. Understanding the temporal and spatial oceanographic variations in physical forcing is essential to understanding the ecological functioning within the Ross Sea. There are a number of models of the physical oceanography of the Ross Sea that characterize the observed circulation. Unfortunately, data on the appropriate time scales (daily, monthly, seasonal, and interannual) to completely evaluate those models are lacking. The proposed research is a demonstration project to characterize the physical and biological oceanography of the southern Ross Sea using newly developed Glider technology to sample the region continuously through the growing season, to collect temperature, salinity, fluorescence, oxygen and optical transmission data. These field data will be used to assist in evaluation of an eddy-resolving ROMS-based coupled circulation-biological model, and, along with satellite ocean color information, will be assimilated into an ecosystem model. Data assimilation techniques will reduce the model uncertainties of the circulation and food webs of the region. The intellectual merit of this effort arises from the combination of field-based investigations using a novel technology (one that is far more cost-effective than ship-based studies) with state-of-the-art biological-physical models and advanced data assimilation techniques. The research will provide new insights into the complex oceanographic phenomena of the Antarctic continental shelves and is a novel method of continuing the studies of the southern Ross Sea. Broader impacts of the proposed research include training of graduate and undergraduate students and partnership with several ongoing outreach programs dealing with scientific research in the Southern Ocean. At least 2 graduate students will be supported by this research, and it will be a critical component of a variety of outreach programs in Virginia, including a High School Marine Science Day, Boy and Girl Scout education, and middle school curriculum improvement. The investigators also will create a web site to foster immediate release of the data collected by the glider, and seek a linkage with schools at various levels (middle, high school and Universities) that potentially could incorporate the data into classroom activities", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hofmann, Eileen; Dinniman, Michael; Klinck, John M.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Seasonal Evolution of Chemical and Biological Variability in the Ross Sea", "uid": "p0000262", "west": null}, {"awards": "0838911 Hofmann, Eileen; 0838892 Burns, Jennifer; 0838937 Costa, Daniel", "bounds_geometry": "POLYGON((160 -68,162 -68,164 -68,166 -68,168 -68,170 -68,172 -68,174 -68,176 -68,178 -68,180 -68,180 -68.8,180 -69.6,180 -70.4,180 -71.2,180 -72,180 -72.8,180 -73.6,180 -74.4,180 -75.2,180 -76,178 -76,176 -76,174 -76,172 -76,170 -76,168 -76,166 -76,164 -76,162 -76,160 -76,160 -75.2,160 -74.4,160 -73.6,160 -72.8,160 -72,160 -71.2,160 -70.4,160 -69.6,160 -68.8,160 -68))", "dataset_titles": "Weddell seal dive behavior and rhythmicity from 2010-2012 in the Ross Sea; Weddell seals as autonomous sensors of the winter oceanography of the Ross Sea", "datasets": [{"dataset_uid": "600101", "doi": "10.15784/600101", "keywords": "Biota; Oceans; Ross Sea; Seals; Southern Ocean", "people": "Burns, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Weddell seals as autonomous sensors of the winter oceanography of the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600101"}, {"dataset_uid": "600025", "doi": "10.15784/600025", "keywords": "Antarctica; Biota; Oceans; Ross Sea; Southern Ocean", "people": "Costa, Daniel", "repository": "USAP-DC", "science_program": null, "title": "Weddell seals as autonomous sensors of the winter oceanography of the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600025"}, {"dataset_uid": "601835", "doi": "10.15784/601835", "keywords": "Aerobic; Antarctica; Cryosphere; Weddell Seal", "people": "Shero, Michelle", "repository": "USAP-DC", "science_program": null, "title": "Weddell seal dive behavior and rhythmicity from 2010-2012 in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601835"}], "date_created": "Mon, 11 Nov 2013 00:00:00 GMT", "description": "Abstract \u003cbr/\u003eThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). \u003cbr/\u003e\u003cbr/\u003eMarine mammals of the Southern Ocean have evolved diverse life history patterns and foraging strategies to accommodate extreme fluctuations in the physical and biological environment. In light of ongoing climate change and the dramatic shifts in the extent and persistence of sea ice in the Ross Sea, it is critical to understand how Weddell seals, Leptonychotes weddellii, a key apex predator, select and utilize foraging habitats. Recent advances in satellite-linked animal-borne conductivity, temperature and depth (CTD) tags make it possible to simultaneously collect data on seal locations, their diving patterns, and the temperature and salinity profiles of the water columns they utilize. In other ecosystems, such data have revealed that marine predators selectively forage in areas where currents and fronts serve to locally concentrate prey resources, and that these conditions are required to sustain populations. Weddell seals will be studied in McMurdo Sound and at Terra Nova Bay, Ross Sea and will provide the first new data on Weddell seal winter diving behavior and habitat use in almost two decades. The relationship between an animal\u0027s diving behavior and physical habitat has enormous potential to enhance monitoring studies and to provide insight into how changes in ice conditions (due either to warming or the impact of large icebergs, such as B15) might impact individual time budgets and foraging success. The second thrust of this project is to use the profiles obtained from CTD seal tags to model the physical oceanography of this region. Current mathematical models of physical oceanographic processes in the Southern Ocean are directed at better understanding the role that it plays in global climate processes, and the linkages between physical and biological oceanographic processes. However, these efforts are limited by the scarcity of oceanographic data at high latitudes in the winter months; CTD tags deployed on animals will collect data at sufficient spatial and temporal resolution to improve data density. The project will contribute to two IPY endorsed initiatives: MEOP (Marine Mammals as Explorers of the Ocean Pole to Pole) and CAML (Census of Antarctic Marine Life). In addition, the highly visual nature of the data and analysis lends itself to public and educational display and outreach, particularly as they relate to global climate change, and we have collaborations with undergraduate and graduate training programs, the Seymour Marine Discovery Center, and the ARMADA program to foster these broader impacts.", "east": 180.0, "geometry": "POINT(170 -72)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -68.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Burns, Jennifer; Hofmann, Eileen; Costa, Daniel", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.0, "title": "Collaborative Research: Weddell seals as autonomous sensors of the winter oceanography of the Ross Sea", "uid": "p0000661", "west": 160.0}, {"awards": "0838955 Gast, Rebecca", "bounds_geometry": "POLYGON((71.504166 -76.159164,71.5142214 -76.159164,71.5242768 -76.159164,71.5343322 -76.159164,71.5443876 -76.159164,71.554443 -76.159164,71.5644984 -76.159164,71.5745538 -76.159164,71.5846092 -76.159164,71.5946646 -76.159164,71.60472 -76.159164,71.60472 -76.2018032,71.60472 -76.2444424,71.60472 -76.2870816,71.60472 -76.3297208,71.60472 -76.37236,71.60472 -76.4149992,71.60472 -76.4576384,71.60472 -76.5002776,71.60472 -76.5429168,71.60472 -76.585556,71.5946646 -76.585556,71.5846092 -76.585556,71.5745538 -76.585556,71.5644984 -76.585556,71.554443 -76.585556,71.5443876 -76.585556,71.5343322 -76.585556,71.5242768 -76.585556,71.5142214 -76.585556,71.504166 -76.585556,71.504166 -76.5429168,71.504166 -76.5002776,71.504166 -76.4576384,71.504166 -76.4149992,71.504166 -76.37236,71.504166 -76.3297208,71.504166 -76.2870816,71.504166 -76.2444424,71.504166 -76.2018032,71.504166 -76.159164))", "dataset_titles": "Alternative Nutritional Strategies in Antarctic Protists", "datasets": [{"dataset_uid": "600103", "doi": "10.15784/600103", "keywords": "Biota; Microbiology; NBP0305; NBP0405; NBP0508; NBP1101; Oceans; Southern Ocean", "people": "Gast, Rebecca", "repository": "USAP-DC", "science_program": null, "title": "Alternative Nutritional Strategies in Antarctic Protists", "url": "https://www.usap-dc.org/view/dataset/600103"}], "date_created": "Wed, 30 Oct 2013 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). \u003cbr/\u003e\u003cbr/\u003eMost organisms meet their carbon and energy needs using photosynthesis (phototrophy) or ingestion/assimilation of organic substances (heterotrophy). However, a nutritional strategy that combines phototrophy and heterotrophy - mixotrophy - is geographically and taxonomically widespread in aquatic systems. While the presence of mixotrophs in the Southern Ocean is known only recently, preliminary evidence indicates a significant role in Southern Ocean food webs. Recent work on Southern Ocean dinoflagellate, Kleptodinium, suggests that it sequesters functional chloroplasts of the bloom-forming haptophyte, Phaeocystis antarctica. This dinoflagellate is abundant in the Ross Sea, has been reported elsewhere in the Southern Ocean, and may have a circumpolar distribution. By combining nutritional modes. mixotrophy may offer competitive advantages over pure autotrophs and heterotrophs. \u003cbr/\u003e\u003cbr/\u003eThe goals of this project are to understand the importance of alternative nutritional strategies for Antarctic species that combine phototrophic and phagotrophic processes in the same organism. The research will combine field investigations of plankton and ice communities in the Southern Ocean with laboratory experiments on Kleptodinium and recently identified mixotrophs from our Antarctic culture collections. The research will address: 1) the relative contributions of phototrophy and phagotrophy in Antarctic mixotrophs; 2) the nature of the relationship between Kleptodinium and its kleptoplastids; 3) the distributions and abundances of mixotrophs and Kleptodinium in the Southern Ocean during austral spring/summer; and 4) the impacts of mixotrophs and Kleptodinium on prey populations, the factors influencing these behaviors and the physiological conditions of these groups in their natural environment. The project will contribute to the maintenance of a culture collection of heterotrophic, phototrophic and mixotrophic Antarctic protists that are available to the scientific community, and it will train graduate and undergraduate students at Temple University. Research findings and activities will be summarized for non-scientific audiences through the PIs\u0027 websites and through other public forums, and will involve middle school teachers via collaboration with COSEE-New England.", "east": 71.60472, "geometry": "POINT(71.554443 -76.37236)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.159164, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gast, Rebecca", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.585556, "title": "Collaborative Research: Alternative Nutritional Strategies in Antarctic Protists", "uid": "p0000490", "west": 71.504166}, {"awards": "1043779 Mellish, Jo-Ann", "bounds_geometry": "POLYGON((165.83333 -77.51528,165.923331 -77.51528,166.013332 -77.51528,166.103333 -77.51528,166.193334 -77.51528,166.283335 -77.51528,166.373336 -77.51528,166.463337 -77.51528,166.553338 -77.51528,166.643339 -77.51528,166.73334 -77.51528,166.73334 -77.55153,166.73334 -77.58778,166.73334 -77.62403,166.73334 -77.66028,166.73334 -77.69653,166.73334 -77.73278,166.73334 -77.76903,166.73334 -77.80528,166.73334 -77.84153,166.73334 -77.87778,166.643339 -77.87778,166.553338 -77.87778,166.463337 -77.87778,166.373336 -77.87778,166.283335 -77.87778,166.193334 -77.87778,166.103333 -77.87778,166.013332 -77.87778,165.923331 -77.87778,165.83333 -77.87778,165.83333 -77.84153,165.83333 -77.80528,165.83333 -77.76903,165.83333 -77.73278,165.83333 -77.69653,165.83333 -77.66028,165.83333 -77.62403,165.83333 -77.58778,165.83333 -77.55153,165.83333 -77.51528))", "dataset_titles": "Thermoregulation in Free-Living Antarctic Seals: The Missing Link in Effective Ecological Modeling", "datasets": [{"dataset_uid": "600130", "doi": "10.15784/600130", "keywords": "Antarctica; Biota; Oceans; Ross Sea; Sea Ice; Seals; Sea Surface; Southern Ocean", "people": "Mellish, Jo-Ann", "repository": "USAP-DC", "science_program": null, "title": "Thermoregulation in Free-Living Antarctic Seals: The Missing Link in Effective Ecological Modeling", "url": "https://www.usap-dc.org/view/dataset/600130"}], "date_created": "Sun, 22 Sep 2013 00:00:00 GMT", "description": "Despite being an essential physiological component of homeotherm life in polar regions, little is known about the energetic requirements for thermoregulation in either air or water for high- latitude seals. In a joint field and modeling study, the principal investigators will quantify these costs for the Weddell seal under both ambient air and water conditions. The field research will include innovative heat flux, digestive and locomotor cost telemetry on 40 free-ranging seals combined with assessments of animal health (morphometrics, hematology and clinical chemistry panels), quantity (ultrasound) and quality (tissue biopsy) of blubber insulation, and determination of surface skin temperature patterns (infrared thermography). Field-collected data will be combined with an established individual based computational energetics model to define cost-added thresholds in body condition for different body masses. This study will fill a major knowledge gap by providing data essential to modeling all aspects of pinniped life history, in particular for ice seals. Such parameterization of energetic cost components will be essential for the accurate modeling of responses by pinnipeds to environmental variance, including direct and indirect effects driven by climate change. The study also will provide extensive opportunities in polar field work, animal telemetry, biochemical analyses and computational modeling for up to three undergraduate students and one post-doctoral researcher. Integrated education and outreach efforts will educate the public (K-12 through adult) on the importance of quantifying energetic costs of thermoregulation for marine mammals and the need to understand responses of species to environmental variance. This effort will include a custom-built, interactive hands-on mobile exhibit, and development of content for an Ocean Today kiosk.", "east": 166.73334, "geometry": "POINT(166.283335 -77.69653)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.51528, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Mellish, Jo-Ann", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.87778, "title": "Collaborative Research: THERMOREGULATION IN FREE-LIVING ANTARCTIC SEALS: THE MISSING LINK IN EFFECTIVE ECOLOGICAL MODELING", "uid": "p0000343", "west": 165.83333}, {"awards": "0838615 Hall, Brenda", "bounds_geometry": "POLYGON((-177.13 -84.55,-177.074 -84.55,-177.018 -84.55,-176.962 -84.55,-176.906 -84.55,-176.85 -84.55,-176.794 -84.55,-176.738 -84.55,-176.682 -84.55,-176.626 -84.55,-176.57 -84.55,-176.57 -84.615,-176.57 -84.68,-176.57 -84.745,-176.57 -84.81,-176.57 -84.875,-176.57 -84.94,-176.57 -85.005,-176.57 -85.07,-176.57 -85.135,-176.57 -85.2,-176.626 -85.2,-176.682 -85.2,-176.738 -85.2,-176.794 -85.2,-176.85 -85.2,-176.906 -85.2,-176.962 -85.2,-177.018 -85.2,-177.074 -85.2,-177.13 -85.2,-177.13 -85.135,-177.13 -85.07,-177.13 -85.005,-177.13 -84.94,-177.13 -84.875,-177.13 -84.81,-177.13 -84.745,-177.13 -84.68,-177.13 -84.615,-177.13 -84.55))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 05 Sep 2013 00:00:00 GMT", "description": "Stone/0838818 \u003cbr/\u003e\u003cbr/\u003eThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). \u003cbr/\u003e\u003cbr/\u003eThis award supports a project to study the former thickness and retreat history of Shackleton and Beardmore Glaciers which flow through the Transantarctic Mountains (TAMs) into the southern Ross Sea. Lateral moraine deposits along the lower reaches of these major outlet glaciers will be mapped and dated and the results will help to date the LGM and constrain the thickness of ice where it left the Transantarctic Mountains and flowed into the Ross Sea. The intellectual merit of the project is that the results will allow scientists to distinguish between models of ice retreat, which have important implications for former ice configuration and dynamics, and to constrain the contribution from Ross Sea deglaciation to global sea level through the late Holocene. In addition, this will make a significant contribution to a better understanding of the magnitude and timing of postglacial sea-level change and the potential contribution of Antarctica to sea-level rise in future. The broader impacts of the project are that the work will help quantify changes in grounded ice volume since the LGM, improve understanding of the ice dynamics responsible, and examine their implications for future sea level change. The project will train future scientists through participation of two graduate students and undergraduates who will develop self-contained research projects. As in previous Antarctic projects, there will be interaction with K-12 students through classroom visits, web-based expedition journals, letters from the field, and discussions with teachers and will allow the project to be shared with a wide audience. This award has field work in Antarctica.", "east": -176.57, "geometry": "POINT(-176.85 -84.875)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -84.55, "nsf_funding_programs": "Antarctic Instrumentation and Support", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Hall, Brenda", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -85.2, "title": "Collaborative Research: Constraints on the last Ross Ice Sheet from Glacial Deposits in the Southern Transantarctic Mountains", "uid": "p0000094", "west": -177.13}, {"awards": "1142083 Kyle, Philip", "bounds_geometry": "POINT(167.15334 -77.529724)", "dataset_titles": "Database of Erebus cave field seasons; Icequakes at Erebus volcano, Antarctica; Mount Erebus Observatory GPS data; Mount Erebus Seismic Data; Mount Erebus Thermodynamic model code; Mount Erebus Volcano Observatory: Operations, Science and Outreach (MEVO-OSO); Seismic data used for high-resolution active-source seismic tomography", "datasets": [{"dataset_uid": "200027", "doi": "", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Mount Erebus Observatory GPS data", "url": "https://www.unavco.org/data/gps-gnss/data-access-methods/dai1/monument.php?mid=22083\u0026parent_link=Permanent\u0026pview=original"}, {"dataset_uid": "600381", "doi": "10.15784/600381", "keywords": "Antarctica; Cable Observatory; Geology/Geophysics - Other; Infrared Imagery; Intracontinental Magmatism; IntraContinental Magmatism; MEVO; Mount Erebus; Photo/video; Photo/Video; Ross Island; Solid Earth; Thermal Camera; Volcano", "people": "Oppenheimer, Clive; Kyle, Philip", "repository": "USAP-DC", "science_program": "MEVO", "title": "Mount Erebus Volcano Observatory: Operations, Science and Outreach (MEVO-OSO)", "url": "https://www.usap-dc.org/view/dataset/600381"}, {"dataset_uid": "200034", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Seismic data used for high-resolution active-source seismic tomography", "url": "http://ds.iris.edu/mda/ZW/?timewindow=2007-2009http://ds.iris.edu/mda/Y4?timewindow=2008-2009http://ds.iris.edu/ds/nodes/dmc/forms/assembled-data/?dataset_report_number=09-015"}, {"dataset_uid": "200033", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Icequakes at Erebus volcano, Antarctica", "url": "http://ds.iris.edu/mda/ZW/?timewindow=2007-2009http://ds.iris.edu/mda/Y4?timewindow=2008-2009http://ds.iris.edu/mda/ZO?timewindow=2011-2012"}, {"dataset_uid": "200032", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Mount Erebus Seismic Data", "url": "http://ds.iris.edu/mda/ER/"}, {"dataset_uid": "200031", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Mount Erebus Thermodynamic model code", "url": "https://github.com/kaylai/Iacovino2015_thermodynamic_model"}, {"dataset_uid": "200030", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Database of Erebus cave field seasons", "url": "https://github.com/foobarbecue/troggle"}], "date_created": "Tue, 03 Sep 2013 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eMt. Erebus is one of only a handful of volcanoes worldwide that have lava lakes with readily observable and nearly continuous Strombolian explosive activity. Erebus is also unique in having a permanent convecting lava lake of anorthoclase phonolite magma. Over the years significant infrastructure has been established at the summit of Mt. Erebus as part of the Mount Erebus Volcano Observatory (MEVO), which serves as a natural laboratory to study a wide range of volcanic processes, especially magma degassing associated with an open convecting magma conduit. The PI proposes to continue operating MEVO for a further five years. The fundamental fundamental research objectives are: to understand diffuse flank degassing by using distributed temperature sensing and gas measurements in ice caves, to understand conduit processes, and to examine the environmental impact of volcanic emissions from Erebus on atmospheric and cryospheric environments. To examine conduit processes the PI will make simultaneous observations with video records, thermal imaging, measurements of gas emission rates and gas compositions, seismic, and infrasound data.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eAn important aspect of Erebus research is the education and training of students. Both graduate and undergraduate students will have the opportunity to work on MEVO data and deploy to the field site. In addition, this proposal will support a middle or high school science teacher for two field seasons. The PI will also continue working with various media organizations and filmmakers.", "east": 167.15334, "geometry": "POINT(167.15334 -77.529724)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e TIRS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e SPECTROMETERS \u003e FTIR SPECTROMETER; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e SPECTROMETERS \u003e DOAS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e LASER RANGING \u003e MOBLAS; IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e ELECTRON MICROPROBES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e PETROGRAPHIC MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e HRDI; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e TIRS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e INFRASONIC MICROPHONES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e AMS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e XRF; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-ES; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e LASER RANGING \u003e MOBLAS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e IRGA; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e SCANNING ELECTRON MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE CHAMBERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e SPECTROMETERS \u003e FTIR SPECTROMETER; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e MICROTOMOGRAPHY; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e SIMS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Earthquakes; Vesuvius; Cosmogenic Radionuclides; Infrasonic Signals; Icequakes; Magma Shells; Phase Equilibria; Passcal; Correlation; Backscattering; Eruptive History; Degassing; Volatiles; Magma Convection; Thermodynamics; Tremors; Optech; Uv Doas; Energy Partitioning; Erebus; Cronus; Holocene; Lava Lake; Phonolite; Vagrant; Thermal Infrared Camera; Flir; USA/NSF; Mount Erebus; Active Source Seismic; GROUND-BASED OBSERVATIONS; Interferometry; Volatile Solubility; Redox State; Viscosity; Hydrogen Emission; Seismicity; Eruptions; Explosion Energy; FIELD SURVEYS; Radar Spectra; OBSERVATION BASED; Seismic Events; Strombolian Eruptions; Anorthoclase; Ice Caves; Iris; VOLCANO OBSERVATORY; Melt Inclusions; Ftir; Alkaline Volcanism; Tomography; TLS; Volcanic Gases; ANALYTICAL LAB", "locations": "Vesuvius; Cronus; Vagrant; Mount Erebus; Passcal", "north": -77.529724, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kyle, Philip; Oppenheimer, Clive; Chaput, Julien; Jones, Laura; Fischer, Tobias", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e VOLCANO OBSERVATORY; OTHER \u003e MODELS \u003e OBSERVATION BASED; OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB", "repo": "UNAVCO", "repositories": "GitHub; IRIS; UNAVCO; USAP-DC", "science_programs": "MEVO", "south": -77.529724, "title": "Mount Erebus Volcano Observatory: Operations, Science and Outreach (MEVO-OSO)", "uid": "p0000383", "west": 167.15334}, {"awards": "1043749 Rouse, Gregory", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1105", "datasets": [{"dataset_uid": "002659", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1105", "url": "https://www.rvdata.us/search/cruise/NBP1105"}], "date_created": "Mon, 24 Jun 2013 00:00:00 GMT", "description": "The west Antarctic Peninsula is warming rapidly, and continuing changes in the thermal regime will likely result in severe consequences for marine fauna, including potential extinction of strongly adapted stenotherms, and invasions from neighboring faunas. Initial impacts of climate change may result in changes in connectivity among populations of the same species. These changes may will be undetectable by direct observation, but may be assessed via genetic connectivity, i.e. differences in allele or haplotype frequencies among populations can be used to infer levels of gene flow. The proposed research will explore the role that the Scotia Arc plays in connecting populations from South America to Antarctica, a corridor identified as a likely entry route for invaders into Antarctica. It also will examine the way in which cryptic species may confound our knowledge of broad-scale distributions, and in doing so, make contributions towards understanding biodiversity and testing the paradigm of circumpolarity in Antarctica. The principal investigator will to collect multi-locus genetic data across \u0027species\u0027 from a broad suite of benthic marine invertebrate phyla, from multiple locations, in order to address hypotheses regarding speciation and connectivity, to estimate demographic population changes, and to identify the underlying processes that drive observed phylogeographic patterns. Comparative phylogeography is a particularly valuable approach because it enables the identification of long-term barriers and refugia common to groups of species and is consequently highly relevant to conservation planning. Moreover, this work will form a valuable baseline for detecting future changes in connectivity. The results of the research will be disseminated through peer-reviewed publications and presentations at conferences. In addition, the project will support the interdisciplinary training of a female graduate student, two undergraduate students, and host additional summer students through the STARS program at SIO, which helps minority students prepare for graduate school. This project will integrate research and education through conducting an interdisciplinary workshop that brings together Earth Science and Biology high school teachers. This workshop aims to assist teachers derive their own curricula uniting plate tectonics, ocean history and evolution, supporting a new high school earth sciences program. Information generated by this project will also directly feed into international efforts to design a series of Marine Protected Areas (MPAs) in Antarctica.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rouse, Gregory", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Using molecular data to test connectivity and the circumpolar paradigm for Antarctic marine invertebrates", "uid": "p0000847", "west": null}, {"awards": "0823101 Ducklow, Hugh", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG1301", "datasets": [{"dataset_uid": "001425", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1301"}, {"dataset_uid": "002731", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1301", "url": "https://www.rvdata.us/search/cruise/LMG1301"}], "date_created": "Mon, 24 Jun 2013 00:00:00 GMT", "description": "Since 1990, Palmer LTER (PAL) research has been guided by the hypothesis that variability in the polar marine ecosystem is mechanistically coupled to changes in the annual advance, retreat and spatial extent of sea ice. Since that time, the hypothesis has been modified to incorporate climate migration, i.e. the displacement of a cold, dry polar climate by a warm, moist climate regime in the northern component of the PAL region, producing fundamental changes in food web structure and elemental cycling. The observed northern changes are affecting all trophic levels and elemental cycling, and the primary mechanism of change involves match-mismatch dynamics. The proposed research builds on previous findings, with a new emphasis on process studies and modeling to elucidate the mechanistic links between teleconnections, climate change, physical oceanographic forcing and ecosystem dynamics. The proposed research will examine the hypothesis that regional warming and sea ice decline associated with historical and on-going climate migration in the northern part of the study area have altered key phenological relationships, leading to changes in species distributions, increasing trophic mismatches and changes in habitat, food availability, ecosystem dynamics and biogeochemical cycling. Through targeted process studies linked to numerical model simulations, the research also will test the hypothesis that deep cross-shelf canyons characterizing the core study region are focal areas for ecosystem processes that result in predictable, elevated food resources for top-predators. The effort includes the addition of 3 new PIs: a zooplankton ecologist with expertise in biogeochemical fluxes, a phytoplankton ecologist focusing on bio-optics and autonomous observations using gliders, and a numerical simulation modeler specializing in coupled global models of ocean circulation, plankton ecology and biogeochemical cycles. The program will add trace metal sampling and analysis, moored physical oceanographic sensors, a moored sediment trap in the south, drifting sediment traps and stable carbon (del 13C) and nitrogen (del 15N) isotope analyses. Missions lasting up to 45 days using gliders deployed before, during and after summer cruises will, along with moorings and satellite remote sensing of sea ice, ocean color, sea surface temperatures and wind fields, greatly extend the observational program in space and time. \u003cbr/\u003e\u003cbr/\u003eSince its inception, PAL has been a leader in Information Management to enable knowledge-building within and beyond the Antarctic, oceanographic and LTER communities. PAL has designed and deployed a new information infrastructure with a relational database architecture to facilitate data distribution and sharing. The Education and Outreach program capitalizes on the public\u0027s fascination with Antarctica to promote scientific literacy from kindergarten students to adult citizens concerned with climate change and environmental sustainability. Through communicating results to the public and working with scientific assessment bodies (e.g., IPCC) and Antarctic Treaty parties to protect Earth\u0027s last frontier, PAL researchers contribute to the national scientific agenda and the greater public benefit.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e PROFILERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ducklow, Hugh", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": "LTER", "south": null, "title": "Palmer, Antarctica Long Term Ecological Research Project", "uid": "p0000874", "west": null}, {"awards": "0839053 Ackley, Stephen", "bounds_geometry": "POLYGON((-180 -67.05,-170.9866 -67.05,-161.9732 -67.05,-152.9598 -67.05,-143.9464 -67.05,-134.933 -67.05,-125.9196 -67.05,-116.9062 -67.05,-107.8928 -67.05,-98.8794 -67.05,-89.866 -67.05,-89.866 -68.1033,-89.866 -69.1566,-89.866 -70.2099,-89.866 -71.2632,-89.866 -72.3165,-89.866 -73.3698,-89.866 -74.4231,-89.866 -75.4764,-89.866 -76.5297,-89.866 -77.583,-98.8794 -77.583,-107.8928 -77.583,-116.9062 -77.583,-125.9196 -77.583,-134.933 -77.583,-143.9464 -77.583,-152.9598 -77.583,-161.9732 -77.583,-170.9866 -77.583,180 -77.583,178.57 -77.583,177.14 -77.583,175.71 -77.583,174.28 -77.583,172.85 -77.583,171.42 -77.583,169.99 -77.583,168.56 -77.583,167.13 -77.583,165.7 -77.583,165.7 -76.5297,165.7 -75.4764,165.7 -74.4231,165.7 -73.3698,165.7 -72.3165,165.7 -71.2632,165.7 -70.2099,165.7 -69.1566,165.7 -68.1033,165.7 -67.05,167.13 -67.05,168.56 -67.05,169.99 -67.05,171.42 -67.05,172.85 -67.05,174.28 -67.05,175.71 -67.05,177.14 -67.05,178.57 -67.05,-180 -67.05))", "dataset_titles": "The Sea Ice System in Antarctic Summer, Oden Southern Ocean Expedition (OSO 2010-11)", "datasets": [{"dataset_uid": "600106", "doi": "10.15784/600106", "keywords": "Ice Core Records; Oceans; Oden; OSO1011; Sea Ice; Sea Ice Salinity; Sea Ice Thickness; Southern Ocean", "people": "Ackley, Stephen", "repository": "USAP-DC", "science_program": null, "title": "The Sea Ice System in Antarctic Summer, Oden Southern Ocean Expedition (OSO 2010-11)", "url": "https://www.usap-dc.org/view/dataset/600106"}], "date_created": "Fri, 03 May 2013 00:00:00 GMT", "description": "Several aspect of the seasonal melting and reformation cycle of Antarctic sea ice appear to be divergent from those occurring in the Arctic. This is most clearly demonstrated by the dramatic diminishing extent and thinning of the Arctic sea ice, to be contrasted to the changes in Antarctic sea-ice extent, which recently (decadaly) shows small increases. Current climate models do not resolve this discrepancy which likely results from both a lack of relevant observational sea-ice data in the Antarctic, along with inadequacies in the physical parameterization of sea-ice properties in climate models.\u003cbr/\u003e\u003cbr/\u003eResearchers will take advantage of the cruise track of the I/B Oden during transit through the Antarctic sea-ice zones in the region of the Bellingshausen, Amundsen and Ross (BAR) seas on a cruise to McMurdo Station. Because of its remoteness and inaccessibility, the BAR region is of considerable scientific interest as being one of the last under described and perhaps unexploited marine ecosystems left on the planet .\u003cbr/\u003e\u003cbr/\u003eA series of on station and underway observations of sea ice properties will be undertaken, thematically linked to broader questions of summer ice survival and baseline physical properties (e.g. estimates of heat and salt fluxes). In situ spatiotemporal variability of sea-ice cover extent, thickness and snow cover depths will be observed.", "east": 165.7, "geometry": "POINT(-142.083 -72.3165)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -67.05, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Ackley, Stephen", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.583, "title": "The Sea Ice System in Antarctic Summer, Oden Southern Ocean Expedition (OSO 2010-11)", "uid": "p0000676", "west": -89.866}, {"awards": "1043621 Weygand, James", "bounds_geometry": "POLYGON((-180 -54.5,-144 -54.5,-108 -54.5,-72 -54.5,-36 -54.5,0 -54.5,36 -54.5,72 -54.5,108 -54.5,144 -54.5,180 -54.5,180 -57,180 -59.5,180 -62,180 -64.5,180 -67,180 -69.5,180 -72,180 -74.5,180 -77,180 -79.5,144 -79.5,108 -79.5,72 -79.5,36 -79.5,0 -79.5,-36 -79.5,-72 -79.5,-108 -79.5,-144 -79.5,-180 -79.5,-180 -77,-180 -74.5,-180 -72,-180 -69.5,-180 -67,-180 -64.5,-180 -62,-180 -59.5,-180 -57,-180 -54.5))", "dataset_titles": "Southern Auroral Electrojet Index", "datasets": [{"dataset_uid": "002542", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Southern Auroral Electrojet Index", "url": "http://vmo.igpp.ucla.edu/search/?words=spase://VMO/NumericalData/SAE/Magnetometer/PT60S"}], "date_created": "Mon, 15 Apr 2013 00:00:00 GMT", "description": "The auroral electrojet index (AE) is used as an indicator of geomagnetic activity at high latitudes representing the strength of auroral electrojet currents in the Northern polar ionosphere. A similar AE index for the Southern hemisphere is not available due to lack of complete coverage the Southern auroral zone (half of which extends over the ocean) with continuous magnetometer observations. While in general global auroral phenomena are expected to be conjugate, differences have been observed in the conjugate observations from the ground and from the Earth\u0027s satellites. These differences indicate a need for an equivalent Southern auroral geomagnetic activity index. The goal of this award is to create the Southern AE (SAE) index that would accurately reflect auroral activity in that hemisphere. With this index, it would be possible to investigate the similarities and the cause of differences between the SAE and \"standard\" AE index from the Northern hemisphere. It would also make it possible to identify when the SAE does not provide a reliable calculation of the Southern hemisphere activity, and to determine when it is statistically beneficial to consider the SAE index in addition to the standard AE while analyzing geospace data from the Northern and Southern polar regions. The study will address these questions by creating the SAE index and its \"near-conjugate\" NAE index from collected Antarctic magnetometer data, and will analyze variations in the cross-correlation of these indices and their differences as a function of geomagnetic activity, season, Universal Time, Magnetic Local Time, and interplanetary magnetic field and solar wind plasma parameters. The broader impact resulting from the proposed effort is in its importance to the worldwide geospace scientific community that currently uses only the standard AE index in a variety of geospace models as necessary input.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -54.5, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Weygand, James", "platforms": "Not provided", "repo": "PI website", "repositories": "PI website", "science_programs": null, "south": -79.5, "title": "A Comparison of Conjugate Auroral Electojet Indices", "uid": "p0000500", "west": -180.0}, {"awards": "0838934 Wiens, Douglas; 0838973 Nyblade, Andrew", "bounds_geometry": "POLYGON((40 -76,50 -76,60 -76,70 -76,80 -76,90 -76,100 -76,110 -76,120 -76,130 -76,140 -76,140 -76.8,140 -77.6,140 -78.4,140 -79.2,140 -80,140 -80.8,140 -81.6,140 -82.4,140 -83.2,140 -84,130 -84,120 -84,110 -84,100 -84,90 -84,80 -84,70 -84,60 -84,50 -84,40 -84,40 -83.2,40 -82.4,40 -81.6,40 -80.8,40 -80,40 -79.2,40 -78.4,40 -77.6,40 -76.8,40 -76))", "dataset_titles": "Seismological Record ID# ZM 2007-12; Seismological Record Network Code# ZM (full data link not provided)", "datasets": [{"dataset_uid": "000152", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Seismological Record Network Code# ZM (full data link not provided)", "url": "http://www.iris.edu/"}, {"dataset_uid": "000149", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Seismological Record ID# ZM 2007-12", "url": "http://www.iris.edu/"}], "date_created": "Mon, 21 Jan 2013 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The high elevations of East Antarctica are critical in localizing the initial Cenozoic glaciation and stabilizing it with respect to melting during warm interglacials. However, the geological history for this region and the geophysical mechanism for maintaining the highlands are poorly understood. In 2007-2009, an array of 24 broadband seismographs (named GAMSEIS) was installed across the Gamburtsev Mountains area of the East Antarctic Plateau as part of the Antarctica?s Gamburtsev Province (AGAP) International Polar Year project. The IPY AGAP/GAMSEIS program included plans by other international partners to install seismographs at locations along the flanks of the Gamburtsev Mountains and in other East Antarctic regions. The proposed project will continue operating six of the deployed AGAP/GAMSEIS stations for two more years together with two new broadband seismic stations added to broaden the geographic scope of the array. Most stations will be located at the existing U.S. Autonomous Geophysical Observatories and the USAP fuel cache locations in order to minimize logistical support. This array, combined with seismographs deployed by China and Japan (and possibly Australia, France, and Italy in near future) will provide a sparse but large-scale network of seismometers for the longer-term studies of the crustal and upper mantle structures underneath the East Antarctic Plateau. Continued reliance on students provides a broader impact to this proposed research and firmly grounds this effort in its educational mission.", "east": 140.0, "geometry": "POINT(90 -80)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Wiens, Douglas; Nyblade, Andrew", "platforms": "Not provided", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -84.0, "title": "Collaborative Research: Polenet East: An International Seismological Network for East Antarctica", "uid": "p0000504", "west": 40.0}, {"awards": "0838914 Wannamaker, Philip", "bounds_geometry": "POLYGON((141.01732 -82.13,144.910279 -82.13,148.803238 -82.13,152.696197 -82.13,156.589156 -82.13,160.482115 -82.13,164.375074 -82.13,168.268033 -82.13,172.160992 -82.13,176.053951 -82.13,179.94691 -82.13,179.94691 -82.351835,179.94691 -82.57367,179.94691 -82.795505,179.94691 -83.01734,179.94691 -83.239175,179.94691 -83.46101,179.94691 -83.682845,179.94691 -83.90468,179.94691 -84.126515,179.94691 -84.34835,176.053951 -84.34835,172.160992 -84.34835,168.268033 -84.34835,164.375074 -84.34835,160.482115 -84.34835,156.589156 -84.34835,152.696197 -84.34835,148.803238 -84.34835,144.910279 -84.34835,141.01732 -84.34835,141.01732 -84.126515,141.01732 -83.90468,141.01732 -83.682845,141.01732 -83.46101,141.01732 -83.239175,141.01732 -83.01734,141.01732 -82.795505,141.01732 -82.57367,141.01732 -82.351835,141.01732 -82.13))", "dataset_titles": "Agglutinated Foraminifera, genome sequencing data; Rift Mechanisms and Thermal Regime of the Lithosphere across Beardmore Glacier Region, Central Transantarctic Mountains, from Magnetotelluric Measurements", "datasets": [{"dataset_uid": "600102", "doi": "10.15784/600102", "keywords": "Antarctica; Magnetotelluric; Potential Field; Solid Earth; Transantarctic Mountains", "people": "Wannamaker, Philip", "repository": "USAP-DC", "science_program": null, "title": "Rift Mechanisms and Thermal Regime of the Lithosphere across Beardmore Glacier Region, Central Transantarctic Mountains, from Magnetotelluric Measurements", "url": "https://www.usap-dc.org/view/dataset/600102"}, {"dataset_uid": "000211", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Agglutinated Foraminifera, genome sequencing data", "url": "http://www.ncbi.nlm.nih.gov/sites/myncbi/collections/public/1vwfrm7rJme2hrzl6smGVhpk-/"}], "date_created": "Mon, 12 Nov 2012 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The investigators will examine competing hypotheses for the mechanism of extension and creation of the Transantarctic Mountains, and evolution of the thermal regimes of rifted West Antarctica and stable East Antarctica using magnetotelluric (MT) profiles. Surrounded almost entirely by ocean ridges, Antarctica is a special tectonic situation because of the need to make accommodation space for rifting in the Transantarctic region. In the MT method, temporal variations in the Earth\u0027s natural electromagnetic field are used as source fields to probe the electrical resistivity structure in the depth range of 1 to 200 km, or more. Geophysical methods, such as MT, are appropriate in Antarctica because of the predominance of thick ice cover over most of the Continent and the difficult operating environment. The proposed effort will consist of approximately 50 sites over a distance approaching 500 km with a 10 km average spacing, oriented normal to the Transantarctic Mountains (TAM), in the Beardmore glacier area. High quality MT soundings will be collected over thick ice sheets using a custom electrode preamp design, updated from previous Antarctic projects. Data acquisition will take place over two field seasons. The primary goals are three-fold: to establish the location of the deeper tectonic transition between East and West Antarctica that may be offset from the physiographic transition at the surface, using deep resistivity structure distinguish between modes of extensional upwelling and magmatism that may be vertically non-uniform, depth and magnitude of quasi-layered deep crustal low resistivity, particularly below West Antarctica, will be used to estimate crustal heat flux into the ice sheet base.", "east": 179.94691, "geometry": "POINT(160.482115 -83.239175)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -82.13, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Earth Sciences", "paleo_time": null, "persons": "Bowser, Samuel; Wannamaker, Philip", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "NCBI GenBank; USAP-DC", "science_programs": null, "south": -84.34835, "title": "Rift Mechanisms and Thermal Regime of the Lithosphere across Beardmore Glacier Region, Central Transantarctic Mountains, from Magnetotelluric Measurements", "uid": "p0000247", "west": 141.01732}, {"awards": "0739464 Cassano, John", "bounds_geometry": "POLYGON((160 -74.5,161.5 -74.5,163 -74.5,164.5 -74.5,166 -74.5,167.5 -74.5,169 -74.5,170.5 -74.5,172 -74.5,173.5 -74.5,175 -74.5,175 -74.9,175 -75.3,175 -75.7,175 -76.1,175 -76.5,175 -76.9,175 -77.3,175 -77.7,175 -78.1,175 -78.5,173.5 -78.5,172 -78.5,170.5 -78.5,169 -78.5,167.5 -78.5,166 -78.5,164.5 -78.5,163 -78.5,161.5 -78.5,160 -78.5,160 -78.1,160 -77.7,160 -77.3,160 -76.9,160 -76.5,160 -76.1,160 -75.7,160 -75.3,160 -74.9,160 -74.5))", "dataset_titles": "Atmosphere-Ocean-Ice Interaction in a Coastal Polynya", "datasets": [{"dataset_uid": "600075", "doi": "10.15784/600075", "keywords": "Antarctica; Atmosphere; Meteorology; Navigation; Oceans; Ross Sea; Sea Ice; Southern Ocean; Terra Nova Bay; UAV", "people": "Cassano, John; Maslanik, Jim", "repository": "USAP-DC", "science_program": null, "title": "Atmosphere-Ocean-Ice Interaction in a Coastal Polynya", "url": "https://www.usap-dc.org/view/dataset/600075"}], "date_created": "Thu, 13 Sep 2012 00:00:00 GMT", "description": "Antarctic polynyas are the ice free zones often persisting in continental sea ice. Characterization of the lower atmosphere properties, air-sea surface heat fluxes and corresponding ocean depth profiles of Antarctic polynyas, especially during strong wind events, is needed for a more detailed understanding of the role of polynya in the production of latent-heat type sea ice and the formation, through brine rejection, of dense ocean bottom waters. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: A key technological innovation, the use of instrumented uninhabited aircraft systems (UAS), will be employed to enable the persistent and safe observation of the interaction of light and strong katabatic wind fields with the Terra Nova Bay (Victoria Land, Antarctica) polynya waters during late winter and early summer time frames. The use of UAS observational platforms on the continent to date has to date been modest, but demonstration of their versatility and effectiveness in surveying and observing mode is a welcome development. The projects use of UAS platforms by University of Colorado and LDEO (Columbia) researchers is both high risk, and potentially transformative for the systematic data measurement tasks that many Antarctic science applications increasingly require.", "east": 175.0, "geometry": "POINT(167.5 -76.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -74.5, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Cassano, John; Maslanik, Jim", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.5, "title": "Collaborative Research: Atmosphere-Ocean-Ice Interaction in a Coastal Polynya", "uid": "p0000678", "west": 160.0}, {"awards": "0537752 Creyts, Timothy; 0538674 Winebrenner, Dale", "bounds_geometry": null, "dataset_titles": "Millennially Averaged Accumulation Rates for Lake Vostok; Modeled Radar Attenuation Rate Profile at the Vostok 5G Ice Core Site, Antarctica", "datasets": [{"dataset_uid": "609501", "doi": "10.7265/N59K485D", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Lake Vostok; Radar Attenuation Rate; Vostok Ice Core", "people": "Studinger, Michael S.; Macgregor, Joseph A.; Matsuoka, Kenichi", "repository": "USAP-DC", "science_program": null, "title": "Modeled Radar Attenuation Rate Profile at the Vostok 5G Ice Core Site, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609501"}, {"dataset_uid": "609500", "doi": "10.7265/N5F769HV", "keywords": "Accumulation Rate; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Lake Vostok", "people": "Waddington, Edwin D.; Studinger, Michael S.; Matsuoka, Kenichi; Macgregor, Joseph A.; Winebrenner, Dale", "repository": "USAP-DC", "science_program": null, "title": "Millennially Averaged Accumulation Rates for Lake Vostok", "url": "https://www.usap-dc.org/view/dataset/609500"}], "date_created": "Thu, 09 Aug 2012 00:00:00 GMT", "description": "0538674\u003cbr/\u003eMatsuoka\u003cbr/\u003eThis award supports a project to evaluate radio-echo intensities in the available SOAR ice-penetrating radar data along grids covering Lake Vostok, and along four regional tracks from Ridge B toward the lake. The project has two objectives; first, it will examine the upper surface of the lake and reflectors hypothesized to be a boundary between the meteoric and accreted ice. They will provide crucial knowledge on the dynamic evolution of the lake. Second, this project will examine a poorly understood echo-free zone within the deep ice in central East Antarctica. This zone may consist of distorted stagnant ice, while its upper boundary may be a shear zone. The SOAR radar data provide a unique resource to examine spatiotemporal water circulation patterns that should be understood in order to select the best direct-sampling strategy to the lake. The Vostok ice core provides a unique opportunity to do this work. First, the path effects, i.e. propagation loss and birefringence, will be derived at the ice-core site using ice temperature, chemistry, and fabric data. Second, lateral variations of the propagation loss will be estimated by tracking chemistry associated with radar-detected isochronous layers, and by inferring temperatures from an ice-flow model that can replicate those layers. Ice-fabric patterns will be inferred from anisotropy in the reflectivity at about 100 radar-track cross-over sites. In terms of broader impacts, a graduate student will be trained to interpret the radar data in the light of radar theory and glaciological context of Lake Vostok and summer workshops for K-12 teachers will be provided in Seattle and New York. This project will contribute to ongoing efforts to study Lake Vostok and will complement the site selection for a North Vostok ice core, which has been proposed by Russia and France as an IPY program.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LASERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e ALTIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e RADAR ALTIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMOMETERS \u003e THERMOMETERS", "is_usap_dc": true, "keywords": "Airborne Radar Sounding; DHC-6; Salinity; Lake Vostok; Antarctic Ice Sheet; Modeling; FIELD SURVEYS; Model Output; Accumulation Rate; MODELS; Numerical Model; Ice Sheet; Not provided; Hydrostatic; Aerogeophysical; Subglacial; Attenuation Rate; Radar; FIELD INVESTIGATION; Model; Circulation; LABORATORY", "locations": "Lake Vostok; Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Matsuoka, Kenichi; Winebrenner, Dale; Creyts, Timothy; Macgregor, Joseph A.; Studinger, Michael S.; Waddington, Edwin D.", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e DHC-6; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e MODELS \u003e MODELS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Deciphering the Deep Ice and the Ice-water Interface over Lake Vostok Using Existing Radar Data", "uid": "p0000090", "west": null}, {"awards": "1241487 Adams, Byron", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 06 Jul 2012 00:00:00 GMT", "description": "This award will support the participation of US scientists in an international planning workshop devoted to discussions of how to best facilitate and coordinate international efforts for terrestrial system studies at the McMurdo Dry Valleys of Antarctica. To date, various aspects of the different Dry Valley landscape features (lakes, soils, glaciers, streams) and their biota have been studied most intensively by US and New Zealand scientists, but these efforts could significantly improve their explanatory power if they were coordinated so as to reduce redundancy, decrease environmental degradation and, most importantly, produce comparable datasets. Additionally, many of the present environmental management programs are based on the past baseline composition and location of biotic communities. As these communities become rearranged across the valleys in the future there is interest in assessing whether today\u0027s management plans are adequate. To efficiently move these research programs forward for the McMurdo Dry Valleys requires a coordinated, interdisciplinary, long-term data monitoring and observation network. \u003cbr/\u003e\u003cbr/\u003eThe ultimate objectives of the workshop are to: i) identify the optimal, complementary suites of measurements required to assess and address key processes associated with environmental change in Dry Valley ecosystems; ii) develop standards and protocols for gathering the most critical biotic and abiotic measurements associated with the key processes driving environmental change; iii) generate a draft data coordination and development plan that will maximize the utility of these data; iv) assess the effectiveness of current McMurdo Dry Valley ASMA (Antarctic Special Management Area) environmental protection guidelines.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Adams, Byron", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "A Planning Workshop for a McMurdo Dry Valleys Terrestrial Observation Network", "uid": "p0000126", "west": null}, {"awards": "0739654 Catania, Ginny; 0739372 Conway, Howard", "bounds_geometry": null, "dataset_titles": "Coastal and Terminus History of the Eastern Amundsen Sea Embayment, West Antarctica, 1972 - 2011; Ice Flow History of the Thwaites Glacier, West Antarctica", "datasets": [{"dataset_uid": "609463", "doi": "10.7265/N5RR1W6X", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Flow Lines; Thwaites Glacier", "people": "Fudge, T. J.; Conway, Howard; Catania, Ginny", "repository": "USAP-DC", "science_program": null, "title": "Ice Flow History of the Thwaites Glacier, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/609463"}, {"dataset_uid": "609522", "doi": "10.7265/N5CC0XNK", "keywords": "Amundsen Sea; Antarctica; Climate Change; Coastline; GIS Data; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Satellite Data Interpretation", "people": "Macgregor, Joseph A.; Catania, Ginny; Andrews, Alan G.; Markowski, Michael", "repository": "USAP-DC", "science_program": null, "title": "Coastal and Terminus History of the Eastern Amundsen Sea Embayment, West Antarctica, 1972 - 2011", "url": "https://www.usap-dc.org/view/dataset/609522"}], "date_created": "Wed, 30 May 2012 00:00:00 GMT", "description": "Catania 0739654\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to study the Amundsen Sea drainage system and improve understanding of the impact of recent glaciological changes as an aid to predicting how this region will change in the future. The intellectual merit of the work is that the Amundsen Sea drainage system has been a recent focus for glaciological research because of rapid changes occurring there as a result of grounding line retreat. The work will focus on the regions of flow transition and will map the internal stratigraphy of the ice sheet across the Thwaites Glacier shear margins and use the age and geometry of radar-detected internal layers to interpret ice flow history. Thwaites Glacier (one of the main pathways for ice drainage in the region) has recently widened and may continue to do so in the near future. Thwaites Glacier may be particularly vulnerable to grounding line retreat because it lacks a well-defined subglacial channel. The subglacial environment exerts strong control on ice flow and flow history will be mapped in the context of bed topography and bed reflectivity. The plan is to use existing ice-penetrating radar data and coordinate with planned upcoming surveys to reduce logistical costs. The work proposed here will take three years to complete but no additional fieldwork in Antarctica is required. More detailed ground-based geophysical (radar and seismic) experiments will be needed at key locations to achieve our overall goal and the work proposed here will aid in identifying those regions. The broader impacts of the project are that it will initiate a new collaboration among radar communities within the US including those that are on the forefront of radar systems engineering and those that are actively involved in radar-derived internal layer and bed analysis. The project will also provide support for a postdoctoral researcher and a graduate student, thus giving them exposure to a variety of methodologies and scientific issues. Finally, there are plans to further develop the \"Wired Antarctica\" website designed by Ginny Catania with the help of a student-teacher. This will allow for the existing lesson plans to be updated to Texas State standards so that they can be used more broadly within state middle and high schools.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e SAR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e TM; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e ALTIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR", "is_usap_dc": true, "keywords": "ERS-1; Coastal; Terminus; LABORATORY; Subglacial; Glacier; Not provided; Thwaites Glacier; Antarctica; LANDSAT; Internal Stratigraphy; West Antarctica; Internal Layers; Amundsen Sea; FIELD INVESTIGATION; FIELD SURVEYS; Glaciers; LANDSAT-5; Radar; Seismic", "locations": "Coastal; Antarctica; Thwaites Glacier; Amundsen Sea; West Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard; Catania, Ginny; Markowski, Michael; Macgregor, Joseph A.; Andrews, Alan G.; Fudge, T. J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e EUROPEAN REMOTE SENSING SATELLITE (ERS) \u003e ERS-1; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e LANDSAT \u003e LANDSAT; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e LANDSAT \u003e LANDSAT-5", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Ice-flow history of the Thwaites Glacier, West Antarctica", "uid": "p0000143", "west": null}, {"awards": "0739769 Fricker, Helen", "bounds_geometry": "POLYGON((-57.22 74.58,-55.343 74.58,-53.466 74.58,-51.589 74.58,-49.712 74.58,-47.835 74.58,-45.958 74.58,-44.081 74.58,-42.204 74.58,-40.327 74.58,-38.45 74.58,-38.45 73.822,-38.45 73.064,-38.45 72.306,-38.45 71.548,-38.45 70.79,-38.45 70.032,-38.45 69.274,-38.45 68.516,-38.45 67.758,-38.45 67,-40.327 67,-42.204 67,-44.081 67,-45.958 67,-47.835 67,-49.712 67,-51.589 67,-53.466 67,-55.343 67,-57.22 67,-57.22 67.758,-57.22 68.516,-57.22 69.274,-57.22 70.032,-57.22 70.79,-57.22 71.548,-57.22 72.306,-57.22 73.064,-57.22 73.822,-57.22 74.58))", "dataset_titles": "Amery Ice Shelf metadata (IRIS); Columbia Glacier metadata (IRIS); Greenland Ice Sheet Seismic Network metadata (IRIS)", "datasets": [{"dataset_uid": "000100", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Amery Ice Shelf metadata (IRIS)", "url": "http://www.iris.edu/mda/X9?timewindow=2004-2007"}, {"dataset_uid": "000101", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Columbia Glacier metadata (IRIS)", "url": "http://www.iris.edu/mda/YM?timewindow=2004-2005"}, {"dataset_uid": "000103", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Greenland Ice Sheet Seismic Network metadata (IRIS)", "url": "http://www.iris.edu/mda/_GLISN"}], "date_created": "Thu, 22 Mar 2012 00:00:00 GMT", "description": "This award supports a project to strengthen collaborations between the various research groups working on iceberg calving. Relatively little is known about the calving process, especially the physics that governs the initiation and propagation of fractures within the ice. This knowledge gap exists in part because of the diverse range in spatial and temporal scales associated with calving (ranging from less than one meter to over a hundred kilometers in length scale). It is becoming increasingly clear that to predict the future behavior of the Antarctic Ice Sheet and its contribution to sea level rise, it is necessary to improve our understanding of iceberg calving processes. Further challenges stem from difficulties in monitoring and quantifying short-time and spatial-scale processes associated with ice fracture, including increased fracturing events in ice shelves or outlet glaciers that may be a precursor to disintegration, retreat or increased calving rates. Coupled, these fundamental problems currently prohibit the inclusion of iceberg calving into numerical ice sheet models and hinder our ability to accurately forecast changes in sea level in response to climate change. Seismic data from four markedly different environmental regimes forms the basis of the proposed research, and researchers most familiar with the datasets will perform all analyses. Extracting the similarities and differences across the full breadth of calving processes embodies the core of the proposed work, combining and improving methods previously developed by each group. Techniques derived from solid Earth seismology, including waveform cross-correlation and clustering will be applied to each data set allowing quantitative process comparisons on a significantly higher level than previously possible. This project will derive catalogues of glaciologically produced seismic events; the events will then be located and categorized based on their location, waveform and waveform spectra both within individual environments and between regions. The intellectual merit of this work is that it will lead to a better understanding of iceberg calving and the teleconnections between seismic events and other geophysical processes around the globe. The broader impacts of this work are that it relates directly to socio-environmental impacts of global change and sea level rise. Strong collaborations will form as a result of this research, including bolstered collaborations between the glacier and ice sheet communities, as well as the glaciology and seismology communities. Outreach and public dissemination of findings will be driven by SIO\u0027s Visualization Center, and Birch Aquarium, hosting presentations devoted to the role of the cryosphere in global change. Time-lapse movies of recent changes at Columbia Glacier will be used to engage potential young scientists. A program of presentations outside the university setting to at-risk and gifted youth will be continued. This study will also involve undergraduates in analyses and interpretation and presentation of the seismic data assembled. The work will also support two junior scientists who will be supported by this project.", "east": 72.949097, "geometry": "POINT(72.8836975 -69.008701)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS", "is_usap_dc": false, "keywords": "PASSCAL; Not provided; Antarctic; SEISMOLOGICAL STATIONS; Iceberg; Seismology; Calving", "locations": "Antarctic", "north": -68.993301, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fricker, Helen", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e PASSCAL; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e SEISMOLOGICAL STATIONS; Not provided", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -69.024101, "title": "An Investigation into the Seismic Signatures Generated by Iceberg Calving and Rifting", "uid": "p0000683", "west": 72.818298}, {"awards": "0839039 Kustka, Adam", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1101; Processed CurrentMeter Data from the Adare Basin near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1101 ", "datasets": [{"dataset_uid": "002653", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1101", "url": "https://www.rvdata.us/search/cruise/NBP1101"}, {"dataset_uid": "601343", "doi": null, "keywords": "Antarctica; Mooring; NBP1101; Ross Sea; Salinity; Southern Ocean; Temperature", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": null, "title": "Processed CurrentMeter Data from the Adare Basin near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1101 ", "url": "https://www.usap-dc.org/view/dataset/601343"}], "date_created": "Tue, 17 Jan 2012 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eAn interdisciplinary team of researchers will focus on describing the high productivity patchiness observed in phytoplankton blooms in the mid to late summer in the Ross Sea, Antarctica. Key hypotheses to be tested and extended are that intrusions of nutrient and micro nutrient (e.g. Fe) rich water masses of the Antarctic modified circumpolar deep water (CDW) up onto continental shelves act to control the biogeochemical response of a large area of the productive Ross Sea coastal region. It is believed that this enhanced productivity may be a significant contributing factor to the global carbon cycle. \u003cbr/\u003e\u003cbr/\u003eA novel sampling strategy to be used to test the above hypotheses will employ a remotely controlled deep (1000m) glider (AUV) to locate and map CDW in near real time measuring C (conductivity), T (temperature), D (pressure) and apparent optical properties, and which will serve to direct further ship-based sampling. \u003cbr/\u003e\u003cbr/\u003eThe adaptive coordination of a polar research vessel with an AUV additionally provides an opportunity to engage in formal and informal education and public outreach on issues in polar research.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Kohut, Josh", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Collaborate Research:Modified Circumpolar Deep Water Intrusions as an Iron Source to the Summer Ross Sea Ecosystem", "uid": "p0000843", "west": null}, {"awards": "0230499 Kieber, David", "bounds_geometry": "POLYGON((-179.99998 -43.58056,-143.999984 -43.58056,-107.999988 -43.58056,-71.999992 -43.58056,-35.999996 -43.58056,0 -43.58056,35.999996 -43.58056,71.999992 -43.58056,107.999988 -43.58056,143.999984 -43.58056,179.99998 -43.58056,179.99998 -46.971468,179.99998 -50.362376,179.99998 -53.753284,179.99998 -57.144192,179.99998 -60.5351,179.99998 -63.926008,179.99998 -67.316916,179.99998 -70.707824,179.99998 -74.098732,179.99998 -77.48964,143.999984 -77.48964,107.999988 -77.48964,71.999992 -77.48964,35.999996 -77.48964,0 -77.48964,-35.999996 -77.48964,-71.999992 -77.48964,-107.999988 -77.48964,-143.999984 -77.48964,-179.99998 -77.48964,-179.99998 -74.098732,-179.99998 -70.707824,-179.99998 -67.316916,-179.99998 -63.926008,-179.99998 -60.5351,-179.99998 -57.144192,-179.99998 -53.753284,-179.99998 -50.362376,-179.99998 -46.971468,-179.99998 -43.58056))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001616", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0409"}], "date_created": "Tue, 17 Jan 2012 00:00:00 GMT", "description": "Areas of the Southern Ocean have spectacular blooms of phytoplankton during the austral spring and early summer. One of the dominant phytoplankton species, the haptophyte Phaeocystis antarctica, is a prolific producer of the organic sulfur compound dimethylsulfoniopropionate (DMSP) and Phaeocystis blooms are associated with some of the world\u0027s highest concentrations of DMSP and its volatile degradation product, dimethylsulfide (DMS). Sulfur, in the form of DMS, is transferred from the oceans to the atmosphere and can affect the chemistry of precipitation and influence cloud properties and possibly climate. DMSP and DMS are also quantitatively significant components of the carbon, sulfur and energy flows in many marine food webs, although very little information is available on these processes in high latitude systems. \u003cbr/\u003e\u003cbr/\u003eThis project will study how solar radiation and iron cycling affect DMSP and DMS production by phytoplankton, and the subsequent utilization of these labile forms of organic matter by the microbial food web. Four interrelated hypotheses will be tested in field-based experiments and in situ observations: 1) solar radiation, including enhanced UV-B due to seasonal ozone depletion, plays an important role in determining the net ecosystem production of DMS in the Ross Sea; 2) development of shallow mixed layers promotes the accumulation of DMS in surface waters, because of enhanced exposure of plankton communities to high doses of solar radiation; 3) DMSP production and turnover represent a significant part of the carbon and sulfur flux through polar food webs; 4) bloom development and resulting nutrient depletion (e.g., iron) will result in high production rates of DMSP and high DMS concentrations and atmospheric fluxes. Results from this study will greatly improve understanding of the underlying mechanisms controlling DMSP and DMS concentrations in polar waters, thereby improving our ability to predict DMS fluxes to the atmosphere from this important climatic region. \u003cbr/\u003e\u003cbr/\u003eBoth Drs. Kieber and Kiene actively engage high school, undergraduate and graduate students in their research and are involved in formal programs that target underrepresented groups (NSF-REU and the American Chemical Society-SEED). This project will continue this type of educational outreach. The PIs also teach undergraduate and graduate courses and incorporation of research experiences into their classes will enrich student learning experiences.", "east": 179.99998, "geometry": "POINT(0 -89.999)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.58056, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kiene, Ronald", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.48964, "title": "Collaborative Research: Impact of Solar Radiation and Nutrients on Biogeochemical Cycling of DMSP and DMS in the Ross Sea, Antarctica", "uid": "p0000582", "west": -179.99998}, {"awards": "0125172 Gordon, Arnold", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0302; Expedition data of NBP0304C; Expedition data of NBP0304D; Expedition data of NBP0402; Expedition data of NBP0408; Expedition data of NBP0501", "datasets": [{"dataset_uid": "001692", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304D"}, {"dataset_uid": "001691", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304C"}, {"dataset_uid": "002638", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0402", "url": "https://www.rvdata.us/search/cruise/NBP0402"}, {"dataset_uid": "002629", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "002627", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "002625", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0304D", "url": "https://www.rvdata.us/search/cruise/NBP0304D"}, {"dataset_uid": "002624", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0304C", "url": "https://www.rvdata.us/search/cruise/NBP0304C"}, {"dataset_uid": "002620", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0408", "url": "https://www.rvdata.us/search/cruise/NBP0408"}, {"dataset_uid": "002588", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0302", "url": "https://www.rvdata.us/search/cruise/NBP0302"}], "date_created": "Tue, 17 Jan 2012 00:00:00 GMT", "description": "This study will investigate how the Antarctic Slope Front and continental slope morphology determine the exchanges of mass, heat, and fresh water between the shelf and the deep ocean, in particular those leading to outflows of dense water into intermediate and deep layers of the adjacent basins and into the world ocean circulation \u003cbr/\u003eWhile the importance to the global ocean circulation and climate of cold water masses originating in the Antarctic is unquestioned, the processes by which these water masses enter the deep ocean circulation are not. The primary goal of this work therefore is to identify the principal physical processes that govern the transfer of shelf-modified dense water into intermediate and deep layers of the adjacent deep ocean. At the same time, it seeks to understand the compensatory poleward flow of waters from the oceanic regime. The upper continental slope has been identified as the critical gateway for the exchange of shelf and deep ocean waters. Here the topography, velocity and density fields associated with the nearly ubiquitous front must strongly influence the advective and turbulent transfer of water properties between the shelf and oceanic regimes. The study has four specific objectives: [1] Determine the mean frontal structure and the principal scales of variability, and estimate the role of the front on cross-slope exchanges and mixing of adjacent water masses; [2] Determine the influence of slope topography and bathymetry on frontal location and outflow of dense Shelf Water; [3] Establish the role of frontal instabilities, benthic boundary layer transports, tides and other oscillatory processes on cross-slope advection and fluxes; and [4] Assess the effect of diapycnal mixing, lateral mixing identified through intrusions, and nonlinearities in the equation of state on the rate of descent and the fate of outflowing, near-freezing Shelf Water.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Gordon, Arnold; Cande, Steven; Visbeck, Martin; Jacobs, Stanley", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Anslope, Cross-slope Exchanges at the Antarctic Slope Front", "uid": "p0000807", "west": null}, {"awards": "0230497 Kiene, Ronald", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0409", "datasets": [{"dataset_uid": "001616", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0409"}, {"dataset_uid": "002640", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0409", "url": "https://www.rvdata.us/search/cruise/NBP0409"}], "date_created": "Tue, 17 Jan 2012 00:00:00 GMT", "description": "Areas of the Southern Ocean have spectacular blooms of phytoplankton during the austral spring and early summer. One of the dominant phytoplankton species, the haptophyte Phaeocystis antarctica, is a prolific producer of the organic sulfur compound dimethylsulfoniopropionate (DMSP) and Phaeocystis blooms are associated with some of the world\u0027s highest concentrations of DMSP and its volatile degradation product, dimethylsulfide (DMS). Sulfur, in the form of DMS, is transferred from the oceans to the atmosphere and can affect the chemistry of precipitation and influence cloud properties and possibly climate. DMSP and DMS are also quantitatively significant components of the carbon, sulfur and energy flows in many marine food webs, although very little information is available on these processes in high latitude systems. \u003cbr/\u003e\u003cbr/\u003eThis project will study how solar radiation and iron cycling affect DMSP and DMS production by phytoplankton, and the subsequent utilization of these labile forms of organic matter by the microbial food web. Four interrelated hypotheses will be tested in field-based experiments and in situ observations: 1) solar radiation, including enhanced UV-B due to seasonal ozone depletion, plays an important role in determining the net ecosystem production of DMS in the Ross Sea; 2) development of shallow mixed layers promotes the accumulation of DMS in surface waters, because of enhanced exposure of plankton communities to high doses of solar radiation; 3) DMSP production and turnover represent a significant part of the carbon and sulfur flux through polar food webs; 4) bloom development and resulting nutrient depletion (e.g., iron) will result in high production rates of DMSP and high DMS concentrations and atmospheric fluxes. Results from this study will greatly improve understanding of the underlying mechanisms controlling DMSP and DMS concentrations in polar waters, thereby improving our ability to predict DMS fluxes to the atmosphere from this important climatic region. \u003cbr/\u003e\u003cbr/\u003eBoth Drs. Kieber and Kiene actively engage high school, undergraduate and graduate students in their research and are involved in formal programs that target underrepresented groups (NSF-REU and the American Chemical Society-SEED). This project will continue this type of educational outreach. The PIs also teach undergraduate and graduate courses and incorporation of research experiences into their classes will enrich student learning experiences.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kiene, Ronald", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Impact of Solar Radiation and Nutrients on Biogeochemical Cycling of DMSP and DMS in the Ross Sea, Antarctica", "uid": "p0000832", "west": null}, {"awards": "0538033 Panter, Kurt", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 14 Sep 2011 00:00:00 GMT", "description": "This project studies glaciovolcanic deposits at Minna Bluff in the western Ross Embayment of Antarctica. Its goal is to determine the history of the Ross Ice Shelf, which is fed by the major ice sheets from both East and West Antarctica. Apart from determining how these ice sheets waxed and waned during a period of dynamic climate change, glaciovolcanic sequences may constrain ice sheet parameters that are critical to numerical models such as thickness, hydrology, and basal thermal regime. This three-year study would map, analyze, and determine the age of key units using 40Ar/39Ar dating. Pilot studies would also be conducted for 36Cl dating of glacial deposits and stable isotope evaluations of alteration. The project offers a complementary record of Ross Ice Shelf behavior to that sampled by ANDRILL. It also improves the general record of McMurdo area volcanostratigraphy, which is important to interpreting landforms, glacial deposits, and ancient ice found in the Dry Valleys.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this project include improving society\u0027s understanding of global climate change, sea level rise, and graduate and undergraduate student education. Outreach efforts include educational programs for public schools and community groups, exhibits for a local science museum, and a project website.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Panter, Kurt", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Proposal: Late Cenozoic Volcanism and Glaciation at Minna Bluff, Antarctica: Implications for Antarctic Cryosphere History", "uid": "p0000252", "west": null}, {"awards": "0838866 Buesseler, Ken", "bounds_geometry": "POLYGON((-75 -62,-74 -62,-73 -62,-72 -62,-71 -62,-70 -62,-69 -62,-68 -62,-67 -62,-66 -62,-65 -62,-65 -62.8,-65 -63.6,-65 -64.4,-65 -65.2,-65 -66,-65 -66.8,-65 -67.6,-65 -68.4,-65 -69.2,-65 -70,-66 -70,-67 -70,-68 -70,-69 -70,-70 -70,-71 -70,-72 -70,-73 -70,-74 -70,-75 -70,-75 -69.2,-75 -68.4,-75 -67.6,-75 -66.8,-75 -66,-75 -65.2,-75 -64.4,-75 -63.6,-75 -62.8,-75 -62))", "dataset_titles": "data deposited with Palmer Long-Term Ecological Research (LTER) repository.", "datasets": [{"dataset_uid": "000215", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "data deposited with Palmer Long-Term Ecological Research (LTER) repository.", "url": "http://pal.lternet.edu/data/"}], "date_created": "Wed, 31 Aug 2011 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eBy using a tool-box of particle flux and characterization techniques appropriate to the study of particulate organic carbon fluxes out of the upper sunlit zone, WHOI researchers will attempt to evaluate the so called \u0027biological pump\u0027 term at the Palmer Long Term Ecological Research (PAL) site in the Western Antarctic Peninsula (WAP). The goal of these measurements is to describe the seasonal dynamics of production, export (sinking) and at-depth remineralization rates of organic matter produced in the Antarctic photic zone. This should lead to a better understanding of the biogeochemical controls on the carbon cycle in this difficult to access region. Additionally, how much of the newly fixed organic carbon is exported off the shelf, effectively driving an influx of atmospheric (including anthropogenic) CO2 to be sequestered into the deep ocean is not presently known. Comparison of prior time series sediment traps in the WAP seem to indicate smaller sinking C fluxes than other, as equally as productive Antarctic coastal regions, e.g. the Ross Sea. New observations and modeling activities will attempt to explain this discrepancy, and to account for the apparently inefficient particle export. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003e\"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\"", "east": -65.0, "geometry": "POINT(-70 -66)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -62.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Buesseler, Ken; Valdes, James", "platforms": "Not provided", "repo": "LTER", "repositories": "LTER", "science_programs": "LTER", "south": -70.0, "title": "WAPflux - New Tools to Study the Fate of Phytoplankton Production in the West Antarctic Peninsula", "uid": "p0000686", "west": -75.0}, {"awards": "0440847 Raymond, Charles", "bounds_geometry": null, "dataset_titles": "GPS-Measured Ice Velocities and Strain Data from the Ross and Amundsen Sea Ice Flow Divide, West Antarctica; Polarimetric Radar Data from the Ross and Amundsen Sea Ice Flow Divide, West Antarctica", "datasets": [{"dataset_uid": "609496", "doi": "10.7265/N5TH8JNG", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Radar; Ross-Amundsen Divide", "people": "Fujita, Shuji; Matsuoka, Kenichi; Power, Donovan; Raymond, Charles", "repository": "USAP-DC", "science_program": null, "title": "Polarimetric Radar Data from the Ross and Amundsen Sea Ice Flow Divide, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/609496"}, {"dataset_uid": "609503", "doi": "10.7265/N5222RQ8", "keywords": "Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ice Flow Velocity; Ross-Amundsen Divide; Strain", "people": "Rasmussen, Al; Power, Donovan; Matsuoka, Kenichi", "repository": "USAP-DC", "science_program": null, "title": "GPS-Measured Ice Velocities and Strain Data from the Ross and Amundsen Sea Ice Flow Divide, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/609503"}], "date_created": "Mon, 29 Aug 2011 00:00:00 GMT", "description": "This award supports a project to investigate fabrics with ground-based radar measurements near the Ross/Amundsen Sea ice-flow divide where a deep ice core will be drilled. The alignment of crystals in ice (crystal-orientation fabric) has an important effect on ice deformation. As ice deforms, anisotropic fabrics are produced, which, in turn, influence further deformation. Measurement of ice fabric variations can help reveal the deformation history of the ice and indicate how the ice will deform in the future. Ice cores provide opportunities to determine a vertical fabric profile, but horizontal variations of fabrics remain unknown. Remote sensing with ice-penetrating radar is the only way to do that over large areas. Preliminary results show that well-established polarimetric methods can detect the degree of horizontal anisotropy of fabrics and their orientation, even when they are nearly vertical-symmetric fabrics. In conjunction with ice deformation history, our first mapping of ice fabrics will contribute to modeling ice flow near the future ice core site. The project will train a graduate student and provide research experiences for two under graduate students both in field and laboratory. The project will contribute to ongoing West Antarctic ice sheet program efforts to better understand the impact of the ice sheet on global sea level rise. This project also supports an international collaboration between US and Japanese scientists.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "GPS; FIELD SURVEYS; Antarctic; Radar; Antarctica; FIELD INVESTIGATION; Ice Sheet; Not provided; Ross-Amundsen Divide; West Antarctica; West Antarctic Ice Sheet", "locations": "Antarctica; Ross-Amundsen Divide; West Antarctica; Antarctic; West Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Matsuoka, Kenichi; Power, Donovan; Fujita, Shuji; Raymond, Charles; Rasmussen, Al", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Detection of Crystal Orientation Fabrics near the Ross/Amundsen Sea Ice-flow Divide and at the Siple Dome Ice Core Site using Polarimetric Radar Methods", "uid": "p0000024", "west": null}, {"awards": "0636818 Stone, John", "bounds_geometry": "POLYGON((-157 -85,-156 -85,-155 -85,-154 -85,-153 -85,-152 -85,-151 -85,-150 -85,-149 -85,-148 -85,-147 -85,-147 -85.3,-147 -85.6,-147 -85.9,-147 -86.2,-147 -86.5,-147 -86.8,-147 -87.1,-147 -87.4,-147 -87.7,-147 -88,-148 -88,-149 -88,-150 -88,-151 -88,-152 -88,-153 -88,-154 -88,-155 -88,-156 -88,-157 -88,-157 -87.7,-157 -87.4,-157 -87.1,-157 -86.8,-157 -86.5,-157 -86.2,-157 -85.9,-157 -85.6,-157 -85.3,-157 -85))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 05 Aug 2011 00:00:00 GMT", "description": "Hall/0636687\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to investigate late Pleistocene and Holocene changes in Scott Glacier, a key outlet glacier that flows directly into the Ross Sea just west of the present-day West Antarctic Ice Sheet (WAIS) grounding line. The overarching goals are to understand changes in WAIS configuration in the Ross Sea sector at and since the last glacial maximum (LGM) and to determine whether Holocene retreat observed in the Ross Embayment has ended or if it is still ongoing. To address these goals, moraine and drift sequences associated with Scott Glacier will be mapped and dated and ice thickness, surface velocity and surface mass balance will be measured to constrain an ice-flow model of the glacier. This model will be used to help interpret the dated geologic sequences. The intellectual merit of the project relates to gaining a better understanding of the West Antarctic Ice Sheet and how changing activity of fast-flowing outlet glaciers and ice streams exerts strong control on the mass balance of the ice sheet. Previous work suggests that grounding-line retreat in the Ross Sea continued into the late Holocene and left open the possibility of ongoing deglaciation as part of a long-term trend. Results from Reedy Glacier, an outlet glacier just behind the grounding line, suggest that retreat may have slowed substantially over the past 2000 years and perhaps even stopped. By coupling the work on Scott Glacier with recent data from Reedy Glacier, the grounding-line position will be bracketed and it should be possible to establish whether the retreat has truly ended or if it is ongoing. The broader impacts of the work relate to the societal relevance of an improved understanding of the West Antarctic ice sheet to establish how it will respond to current and possible future environmental changes. The work addresses this key goal of the West Antarctic Ice Sheet Initiative, as well as the International Polar Year focus on ice sheet history and dynamics. The work will develop future scientists through the education and training of one undergraduate and two Ph.D. students, interaction with K-12 students through classroom visits, web-based \u0027expedition\u0027 journals, letters from the field, and discussions with teachers. Results from this project will be posted with previous exposure dating results from Antarctica, on the University of Washington Cosmogenic Nuclide Lab website, which also provides information about chemical procedures and calculation methods to other scientists working with cosmogenic nuclides.", "east": -147.0, "geometry": "POINT(-152 -86.5)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -85.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Stone, John; Conway, Howard", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -88.0, "title": "Collaborative Research:Grounding-line Retreat in the Southern Ross Sea - Constraints from Scott Glacier", "uid": "p0000149", "west": -157.0}, {"awards": "0636719 Joughin, Ian; 0636970 Tulaczyk, Slawek", "bounds_geometry": null, "dataset_titles": "Antarctic Active Subglacial Lake Inventory from ICESat Altimetry", "datasets": [{"dataset_uid": "601439", "doi": "10.15784/601439", "keywords": "Altimetry; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Icesat; Laser Altimetry; Subglacial Lake", "people": "Fricker, Helen; Tulaczyk, Slawek; Joughin, Ian; Smith, Ben", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Active Subglacial Lake Inventory from ICESat Altimetry", "url": "https://www.usap-dc.org/view/dataset/601439"}], "date_created": "Wed, 27 Jul 2011 00:00:00 GMT", "description": "Tulaczyk/0636970\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to study elevation change anomalies (henceforth ECAs), which are oval-shaped, 5-to-10 km areas observed in remote sensing images in several locations within the Ross Sea sector of the West Antarctic Ice Sheet (WAIS). Within these anomalies, surface elevation changes at rates of up to ~1 to ~2 cm per day, significantly faster than in surrounding regions. These anomalies are thought to result from filling and draining of multi-kilometer-scale subglacial water pockets. The intellectual merit of this project is that these ECA\u0027s represent an unprecedented window into the elusive world of water drainage dynamics beneath the modern Antarctic ice sheet. Although subglacial water fluxes are small compared to normal terrestrial conditions, they play an important role in controlling fast ice streaming and, potentially, stability of the ice sheet. The dearth of observational constraints on sub-ice sheet water dynamics represents one of the most important limitations on progress in quantitative modeling of ice streams and ice sheets. Such models are necessary to assess future ice sheet mass balance and to reconstruct the response of ice sheets to past climate changes. The dynamic sub-ice sheet water transport indicated by the ECAs may have also implications for studies of subglacial lakes and other subglacial environments, which may harbor life adapted to such extreme conditions. The broader impacts of this project are that it will provide advanced training opportunities to one postdoctoral fellow (UW), two female doctoral students (UCSC), who will enhance diversity in polar sciences, and at least three undergraduate students (UCSC). Project output will be relevant to broad scientific and societal interests, such as the future global sea level changes and the response of Polar Regions to climate changes. Douglas Fox, a freelance science journalist, is interested in joining the first field season to write feature articles to popular science magazines and promote the exposure of this project, and Antarctic Science in general, to mass media.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e LIDAR/LASER ALTIMETERS \u003e GLAS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e LIDAR/LASER ALTIMETERS \u003e GLAS", "is_usap_dc": false, "keywords": "ICESAT; Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Smith, Ben; Joughin, Ian; Tulaczyk, Slawek; SMITH, BENJAMIN", "platforms": "Not provided; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e ICE, CLOUD AND LAND ELEVATION SATELLITE (ICESAT) \u003e ICESAT", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Elevation Change Anomalies in West Antarctica and Dynamics of Subglacial Water Transport Beneath Ice Streams and their Tributaries", "uid": "p0000115", "west": null}, {"awards": "0538120 Catania, Ginny; 0538015 Hulbe, Christina", "bounds_geometry": "POLYGON((154.71 -82.78,154.79000000000002 -82.78,154.87 -82.78,154.95 -82.78,155.03 -82.78,155.11 -82.78,155.19 -82.78,155.26999999999998 -82.78,155.35 -82.78,155.43 -82.78,155.51 -82.78,155.51 -82.788,155.51 -82.796,155.51 -82.804,155.51 -82.812,155.51 -82.82,155.51 -82.828,155.51 -82.836,155.51 -82.844,155.51 -82.852,155.51 -82.86,155.43 -82.86,155.35 -82.86,155.26999999999998 -82.86,155.19 -82.86,155.11 -82.86,155.03 -82.86,154.95 -82.86,154.87 -82.86,154.79000000000002 -82.86,154.71 -82.86,154.71 -82.852,154.71 -82.844,154.71 -82.836,154.71 -82.828,154.71 -82.82,154.71 -82.812,154.71 -82.804,154.71 -82.796,154.71 -82.788,154.71 -82.78))", "dataset_titles": "Grounding Line Strain Grid Surveys, Kamb Ice Stream, Antarctica; Ice-Penetrating Radar Data Across Siple Coast Grounding Lines", "datasets": [{"dataset_uid": "609494", "doi": "10.7265/N5Z899C6", "keywords": "Antarctica; Geodesy; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Grounding Line; Kamb Ice Stream; Strain", "people": "Hulbe, Christina", "repository": "USAP-DC", "science_program": null, "title": "Grounding Line Strain Grid Surveys, Kamb Ice Stream, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609494"}, {"dataset_uid": "609474", "doi": "10.7265/N5M043BH", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; GPR; Grounding Line; Radar; Siple Coast", "people": "Hulbe, Christina; Catania, Ginny", "repository": "USAP-DC", "science_program": null, "title": "Ice-Penetrating Radar Data Across Siple Coast Grounding Lines", "url": "https://www.usap-dc.org/view/dataset/609474"}], "date_created": "Sat, 02 Jul 2011 00:00:00 GMT", "description": "0538120\u003cbr/\u003eCatania\u003cbr/\u003eThis award supports a project to identify and map ice surface and internal features that chronicle the sequence of events leading to the shut-down of Kamb ice stream. In particular, the project will study past grounding line migration and the relationship between that process and ice stream shutdown. The intellectual merits of the project include the fact that an understanding of such processes has important implications for our ability to accurately predict mass balance changes in this region. Currently, one of the five major West Antarctic ice streams, Kamb, is quiescent, and another, Whillans, is slowing in its downstream reaches. The Kamb shutdown appears to have begun at its downstream end but beyond that simple observation, it is not possible, yet, to draw meaningful comparisons between the two adjacent streams. We do not know if current events on Whillans Ice Stream are similar to what transpired during the Kamb shut-down. The work proposed here intends to bridge that gap. It is expected that this effort will yield useful insights into the influence of grounding line dynamics on ice stream flow. The work will involve a combination of field investigations using radio-echo sounding and GPS combined with computational efforts involving the interpretation of ice-surface features such as relict flow traces and crevasses. The broader impacts of the project will be in addressing a global environmental problem with critical societal implications, training the next generation of scientists and engineers to serve the nation, and encouraging women to pursue scientific or engineering careers. Participants from both institutions are involved in a range of public outreach activities.", "east": 155.51, "geometry": "POINT(155.11 -82.82)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR", "is_usap_dc": true, "keywords": "Not provided; Ice Sheet Elevation; West Antarctic Ice Stream; MODELS; Ice Sheet Thickness; West Antarctic Ice Sheet; Kamb Ice Stream; Antarctic Ice Sheet; Ice Sheet; Ice Stream Motion; Antarctica; Siple Dome; Grounding Line; FIELD INVESTIGATION; GPS; FIELD SURVEYS; West Antarctica; Ice Stream; Radar", "locations": "Antarctica; Kamb Ice Stream; West Antarctic Ice Stream; Antarctic Ice Sheet; West Antarctica; West Antarctic Ice Sheet; Siple Dome", "north": -82.78, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Hulbe, Christina; Catania, Ginny", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e MODELS \u003e MODELS; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.86, "title": "Collaborative Research: Grounding Line Forensics: The History of Grounding Line Retreat in the Kamb Ice Stream Outlet Region", "uid": "p0000019", "west": 154.71}, {"awards": "0529666 Fritsen, Christian; 0528728 Vernet, Maria; 0529087 Ross, Robin", "bounds_geometry": "POLYGON((-69.08 -64.8,-68.632 -64.8,-68.184 -64.8,-67.736 -64.8,-67.288 -64.8,-66.84 -64.8,-66.392 -64.8,-65.944 -64.8,-65.496 -64.8,-65.048 -64.8,-64.6 -64.8,-64.6 -65.121,-64.6 -65.442,-64.6 -65.763,-64.6 -66.084,-64.6 -66.405,-64.6 -66.726,-64.6 -67.047,-64.6 -67.368,-64.6 -67.689,-64.6 -68.01,-65.048 -68.01,-65.496 -68.01,-65.944 -68.01,-66.392 -68.01,-66.84 -68.01,-67.288 -68.01,-67.736 -68.01,-68.184 -68.01,-68.632 -68.01,-69.08 -68.01,-69.08 -67.689,-69.08 -67.368,-69.08 -67.047,-69.08 -66.726,-69.08 -66.405,-69.08 -66.084,-69.08 -65.763,-69.08 -65.442,-69.08 -65.121,-69.08 -64.8))", "dataset_titles": "Expedition data of NBP0103; The Dynamic Coupling among Phytoplankton, Ice, Ice Algae and Krill (PIIAK)", "datasets": [{"dataset_uid": "002595", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0103", "url": "https://www.rvdata.us/search/cruise/NBP0103"}, {"dataset_uid": "600050", "doi": "10.15784/600050", "keywords": "Bellingshausen Sea; Cryosphere; Oceans; Photosynthetically Active Radiation (par); Sea Ice; Sea Surface; Southern Ocean; Total Integrated Exposure To PAR", "people": "Fritsen, Christian", "repository": "USAP-DC", "science_program": null, "title": "The Dynamic Coupling among Phytoplankton, Ice, Ice Algae and Krill (PIIAK)", "url": "https://www.usap-dc.org/view/dataset/600050"}, {"dataset_uid": "600049", "doi": "10.15784/600049", "keywords": "Bellingshausen Sea; Biota; Oceans; Southern Ocean", "people": "Ross, Robin Macurda; Quetin, Langdon B.", "repository": "USAP-DC", "science_program": null, "title": "The Dynamic Coupling among Phytoplankton, Ice, Ice Algae and Krill (PIIAK)", "url": "https://www.usap-dc.org/view/dataset/600049"}, {"dataset_uid": "600048", "doi": "10.15784/600048", "keywords": "Bellingshausen Sea; Biota; Oceans; Phytoplankton; Southern Ocean", "people": "Vernet, Maria", "repository": "USAP-DC", "science_program": null, "title": "The Dynamic Coupling among Phytoplankton, Ice, Ice Algae and Krill (PIIAK)", "url": "https://www.usap-dc.org/view/dataset/600048"}], "date_created": "Sat, 02 Apr 2011 00:00:00 GMT", "description": "This collaborative study between the Desert Research Institute, the University of California, Santa Barbara (0529087; Robin Ross), and the University of California, San Diego (0528728; Maria Vernet) will examine the relationship between sea ice extent along the Antarctic Peninsula and the life history of krill (Euphausia superba), by developing, refining, and linking diagnostic datasets and models of phytoplankton decreases in the fall, phytoplankton biomass incorporation into sea ice, sea ice growth dynamics, sea ice algal production and biomass accumulation, and larval krill energetics, condition, and survival. Krill is a key species in the food web of the Southern Ocean ecosystem, and one that is intricately involved with seasonal sea ice dynamics. Results from the Southern Ocean experiment of the Global Ocean Ecosystems Dynamics program (SO-Globec) field work as well as historical information on sea ice dynamics and krill recruitment suggest a shift in the paradigm that all pack ice is equally good krill habitat.\u003cbr/\u003e\u003cbr/\u003eSO-Globec is a multidisciplinary effort focused on understanding the physical and biological factors that influence growth, reproduction, recruitment and survival of Antarctic krill (Euphausia superba). The program uses a multi-trophic level approach that includes the predators and competitors of Antarctic krill, represented by other zooplankton, fish, penguins, seals, and cetaceans. It is currently in a synthesis and modeling phase. This collaborative project is concerned with the lower trophic levels, and will be integrated with other synthesis and modeling studies that deal with grazers, predators, and other higher trophic levels.", "east": -64.6, "geometry": "POINT(-66.84 -66.405)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": true, "keywords": "R/V NBP; Not provided", "locations": null, "north": -64.8, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Fritsen, Christian; Vernet, Maria; Ross, Robin Macurda; Quetin, Langdon B.", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -68.01, "title": "Collaborative Research: U.S. SO GLOBEC Synthesis and Modeling: Timing is Everything: The Dynamic Coupling among Phytoplankton, Ice, Ice Algae and Krill (PIIAK)", "uid": "p0000522", "west": -69.08}, {"awards": "0839069 Yager, Patricia", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1005", "datasets": [{"dataset_uid": "002654", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1005", "url": "https://www.rvdata.us/search/cruise/NBP1005"}], "date_created": "Thu, 03 Mar 2011 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eThe Amundsen Sea Polynya is areally the most productive Antarctic polynya, exhibits higher chlorophyll levels during peak bloom and greater interannual variability than the better-studied Ross Sea Polynya ecosystem. Polynyas may be the key to understanding the future of polar regions as their extent is expected to increase with anthropogenic warming. The project will examine 1) sources of iron to the Amundsen Sea Polynya as a function of climate forcing, 2) phytoplankton community structure in relation to iron supply and mixed-layer depths, 3) the efficiency of the biological pump of carbon to depth and 4) the net flux of carbon as a function of climate and micronutrient forcing. The research also will compare results for the Amundsen Sea to existing data synthesis and modeling efforts for the Palmer LTER and Ross Sea. The project will 1) build close scientific collaborations between US and Swedish researchers; 2) investigate climate change implications with broad societal relevance; 3) train new researchers; 4) encourage participation in research science by underrepresented groups, and 5) involve broad dissemination of results via scientific literature and public outreach, including close interactions with NSF-supported PolarTrec and COSEE K-12 teachers.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Yager, Patricia", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative research aboard Icebreaker Oden: ASPIRE (Amundsen Sea Polynya International Research Expedition)", "uid": "p0000844", "west": null}, {"awards": "0741348 Torres, Joseph", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1002", "datasets": [{"dataset_uid": "002652", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1002", "url": "https://www.rvdata.us/search/cruise/NBP1002"}], "date_created": "Thu, 03 Mar 2011 00:00:00 GMT", "description": "Intellectual Merit: Pleuragramma antarcticum, the Antarctic silverfish, play a key role in the trophic pyramid of the Antarctic coastal ecosystem, acting as food for larger fishes, flying and non-flying seabirds, pinnipeds, and whales. In turn, they are predators on coastal euphausiids, including both Euphausia superba and crystallorophias. Historically, Pleuragramma have been an important food source for Ad\u00e9lie Penguins of the Western Antarctic Peninsula (WAP), but during the last decade Pleuragramma have disappeared from the Ad\u00e9lie diet. We suggest that Pleuragramma?s absence from the diets of top predators is linked to the declining sea ice canopy, which serves as a nursery for eggs and larvae during the austral spring. The research will investigate four hydrographic regimes over the WAP continental shelf with the following features: (1) persistent gyral flows that act to retain locally spawned larvae, (2) spring sea ice that has declined in recent years (3) the prevalence of adult silverfish, and (4) the presence of breeding Ad\u00e9lie penguins whose diets vary in the proportions of silverfish consumed. The research will evaluate the importance of local reproduction versus larval advection, and the extent to which populations in the subregions of study are genetically distinct, via analysis of population structure, otolith microchemistry and molecular genetics of fish. The Pleuragramma data will be compared with penguin diet samples taken synoptically. \u003cbr/\u003e\u003cbr/\u003eBroader Impacts: The proposed research brings together an international group of scientists with highly complimentary suites of skills to address the fate of Pleuragramma on the WAP shelf. Graduate students will use the data acquired as part of their Ph.D research, and will receive cross-training in ornithological field techniques, molecular genetic methods and otolith isotope chemistry. The PIs will work actively with the St. Petersburg Times to produce a blog in real time with pictures and text, which will be used to interact with local schools while we are at sea and after our return. The investigators also will collaborate with the COSEE center at USF and at local schools and museums to disseminate results to the K-12 community throughout the region.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Torres, Joseph", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative research: Possible climate-induced change in the distribution of Pleuragramma antarcticum on the Western Antarctic Peninsula shelf", "uid": "p0000842", "west": null}, {"awards": "9909367 Leventer, Amy", "bounds_geometry": "POLYGON((26.27227 -42.81742,38.414467 -42.81742,50.556664 -42.81742,62.698861 -42.81742,74.841058 -42.81742,86.983255 -42.81742,99.125452 -42.81742,111.267649 -42.81742,123.409846 -42.81742,135.552043 -42.81742,147.69424 -42.81742,147.69424 -45.454494,147.69424 -48.091568,147.69424 -50.728642,147.69424 -53.365716,147.69424 -56.00279,147.69424 -58.639864,147.69424 -61.276938,147.69424 -63.914012,147.69424 -66.551086,147.69424 -69.18816,135.552043 -69.18816,123.409846 -69.18816,111.267649 -69.18816,99.125452 -69.18816,86.983255 -69.18816,74.841058 -69.18816,62.698861 -69.18816,50.556664 -69.18816,38.414467 -69.18816,26.27227 -69.18816,26.27227 -66.551086,26.27227 -63.914012,26.27227 -61.276938,26.27227 -58.639864,26.27227 -56.00279,26.27227 -53.365716,26.27227 -50.728642,26.27227 -48.091568,26.27227 -45.454494,26.27227 -42.81742))", "dataset_titles": "Diatom assemblages from Edward VIII Gulf, Kemp Coast, East Antarctica; NB0101 Expedition Data; Quantitative Diatom Assemblage Data from Iceberg Alley, Mac. Robertson Shelf, East Antarctica acquired during expedition NBP0101", "datasets": [{"dataset_uid": "001879", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NB0101 Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0101"}, {"dataset_uid": "601177", "doi": "10.15784/601177", "keywords": "Antarctica; Biota; Diatom; East Antarctica; Microscopy; NBP0101; Oceans; Paleoceanography; Paleoclimate; R/v Nathaniel B. Palmer; Sediment Corer", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "Diatom assemblages from Edward VIII Gulf, Kemp Coast, East Antarctica", "url": "https://www.usap-dc.org/view/dataset/601177"}, {"dataset_uid": "601307", "doi": null, "keywords": "Antarctica; Biota; Diatom; East Antarctica; Mac. Robertson Shelf; Marine Geoscience; Microscope; NBP0101; Paleoclimate; Piston Corer; R/v Nathaniel B. Palmer; Sediment Core; Species Abundance", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "Quantitative Diatom Assemblage Data from Iceberg Alley, Mac. Robertson Shelf, East Antarctica acquired during expedition NBP0101", "url": "https://www.usap-dc.org/view/dataset/601307"}], "date_created": "Thu, 03 Mar 2011 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a multi-institutional, international (US - Australia) marine geologic and geophysical investigation of Prydz Bay and the MacRobertson Shelf, to be completed during an approximately 60-day cruise aboard the RVIB N.B. Palmer. The primary objective is to develop a record of climate and oceanographic change during the Quaternary, using sediment cores collected via kasten and jumbo piston coring. Core sites will be selected based on seismic profiling (Seabeam 2112 and Bathy2000). Recognition of the central role of the Antarctic Ice Sheet to global oceanic and atmospheric systems is based primarily on data collected along the West Antarctic margin, while similar extensive and high resolution data sets from the much more extensive East Antarctic margin are sparse. Goals of this project include (1) development of a century- to millennial-scale record of Holocene paleoenvironments, and (2) testing of hypotheses concerning the sedimentary record of previous glacial and interglacial events on the shelf, and evaluation of the timing and extent of maximum glaciation along this 500 km stretch of the East Antarctic margin. \u003cbr/\u003e\u003cbr/\u003eHigh-resolution seismic mapping and coring of sediments deposited in inner shelf depressions will be used to reconstruct Holocene paleoenvironments. In similar depositional settings in the Antarctic Peninsula and Ross Sea, sedimentary records demonstrate millennial- and century- scale variability in primary production and sea-ice extent during the Holocene, which have been linked to chronological periodicities in radiocarbon distribution, suggesting the possible role of solar variability in driving some changes in Holocene climate. Similar high-resolution Holocene records from the East Antarctic margin will be used to develop a circum-Antarctic suite of data regarding the response of southern glacial and oceanographic systems to late Quaternary climate change. In addition, these data will help us to evaluate the response of the East Antarctic margin to global warming. \u003cbr/\u003e\u003cbr/\u003eInitial surveys of the Prydz Channel - Amery Depression region reveal sequences deposited during previous Pleistocene interglacials. The upper Holocene and lower (undated) siliceous units can be traced over 15,000 km2 of the Prydz Channel, but more sub-bottom seismic reflection profiling in conjunction with dense coring over this region is needed to define the spatial distribution and extent of the units. Chronological work will determine the timing and duration of previous periods of glacial marine sedimentation on the East Antarctic margin during the late Pleistocene. \u003cbr/\u003e\u003cbr/\u003eAnalyses will focus on detailed sedimentologic, geochemical, micropaleontological, and paleomagnetic techniques. This multi-parameter approach is the most effective way to extract a valuable paleoenvironmental signal in these glacial marine sediments. These results are expected to lead to a significant advance in understanding of the behavior of the Antarctic ice-sheet and ocean system in the recent geologic past.\u003cbr/\u003e\u003cbr/\u003eThe combination of investigators, all with many years of experience working in high latitude marine settings, will provide an effective team to complete the project. University and College faculty (Principal Investigators on this project) will supervise a combination of undergraduate and post-graduate students involved in all stages of the project so that educational objectives will be met in tandem with the research goals of the project.", "east": 147.69424, "geometry": "POINT(86.983255 -56.00279)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": false, "keywords": "R/V NBP; USAP-DC", "locations": null, "north": -42.81742, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Leventer, Amy", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -69.18816, "title": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin", "uid": "p0000609", "west": 26.27227}, {"awards": "0732535 Arrigo, Kevin", "bounds_geometry": "POLYGON((-130 -67,-127.1 -67,-124.2 -67,-121.3 -67,-118.4 -67,-115.5 -67,-112.6 -67,-109.7 -67,-106.8 -67,-103.9 -67,-101 -67,-101 -67.9,-101 -68.8,-101 -69.7,-101 -70.6,-101 -71.5,-101 -72.4,-101 -73.3,-101 -74.2,-101 -75.1,-101 -76,-103.9 -76,-106.8 -76,-109.7 -76,-112.6 -76,-115.5 -76,-118.4 -76,-121.3 -76,-124.2 -76,-127.1 -76,-130 -76,-130 -75.1,-130 -74.2,-130 -73.3,-130 -72.4,-130 -71.5,-130 -70.6,-130 -69.7,-130 -68.8,-130 -67.9,-130 -67))", "dataset_titles": "GEOTRACES International Data Assembly Centre Accession# NIO100280", "datasets": [{"dataset_uid": "000212", "doi": "", "keywords": null, "people": null, "repository": "GEOTRACES", "science_program": null, "title": "GEOTRACES International Data Assembly Centre Accession# NIO100280", "url": "http://www.bodc.ac.uk/geotraces/"}], "date_created": "Thu, 24 Feb 2011 00:00:00 GMT", "description": "IPY: Shedding dynamic light on iron limitation: The interplay of iron\u003cbr/\u003elimitation and dynamic irradiance in governing the phytoplankton\u003cbr/\u003edistribution in the Ross Sea\u003cbr/\u003e\u003cbr/\u003eThe Southern Ocean plays an important role in the global carbon cycle, accounting for approximately 25% of total anthropogenic CO2 uptake by the oceans, mainly via primary production. In the Ross Sea, primary production is dominated by two taxa that are distinct in location and timing. Diatoms dominate in the shallow mixed layer of the continental shelf, whereas the colony forming Phaeocystis antarctica (Prymnesiophyceae) dominate in the more deeply mixed, open regions. Significantly, both groups have vastly different nutrient utilization characteristics, and support very different marine food webs. Their responses to climate change, and the implications for carbon export, are unclear. Previous studies show that light availability and the quality of the light climate (static versus dynamic) play a major role in defining where and when the different phytoplankton taxa bloom. However, iron (Fe) limitation of the algal communities in both the sub-Arctic and the Southern Ocean is now well documented. Moreover, phytoplankton Fe demand varies as a function of irradiance. The main hypothesis of the proposed research is: The interaction between Fe limitation and dynamic irradiance governs phytoplankton distributions in the Ross Sea. Our strategy to test this hypothesis is three-fold: 1) The photoacclimation of the different phytoplankton taxa to different light conditions under Fe limitation will be investigated in experiments in the laboratory under controlled Fe conditions. 2) The photophysiological mechanisms found in these laboratory experiments will then be tested in the field on two cruises with international IPY partners. 3) Finally, data generated during the lab and field parts of the project will be used to parameterize a dynamic light component of the Coupled Ice Atmosphere and Ocean (CIAO) model of the Ross Sea. Using the improved model, we will run future climate scenarios to test the impact of climate change on the phytoplankton community structure, distribution, primary production and carbon export in the Southern Ocean. The proposed research complies with IPY theme\" Understanding Environmental change in Polar Regions\" and includes participation in an international cruise. Detailed model descriptions and all of the results generated from these studies will be made public via a DynaLiFe website. Improving the CIAO model will give us and other IPY partners the opportunity to test the ecological consequences of physiological characteristics observed in Antarctic phytoplankton under current and future climate scenarios. Outreach will include participation in Stanford\u0027s Summer Program for Professional Development for Science Teachers, Stanford\u0027s School of Earth Sciences high school internship program, and development of curriculum for local science training centers, including the Chabot Space and Science Center.", "east": -101.0, "geometry": "POINT(-115.5 -71.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -67.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Arrigo, Kevin", "platforms": "Not provided", "repo": "GEOTRACES", "repositories": "GEOTRACES", "science_programs": null, "south": -76.0, "title": "IPY: Shedding dynamic light on iron limitation: The interplay of iron limitation and dynamic irradiance in governing the phytoplankton distribution in the Ross Sea", "uid": "p0000112", "west": -130.0}, {"awards": "0538479 Seibel, Brad", "bounds_geometry": "POLYGON((166 -77,166.1 -77,166.2 -77,166.3 -77,166.4 -77,166.5 -77,166.6 -77,166.7 -77,166.8 -77,166.9 -77,167 -77,167 -77.1,167 -77.2,167 -77.3,167 -77.4,167 -77.5,167 -77.6,167 -77.7,167 -77.8,167 -77.9,167 -78,166.9 -78,166.8 -78,166.7 -78,166.6 -78,166.5 -78,166.4 -78,166.3 -78,166.2 -78,166.1 -78,166 -78,166 -77.9,166 -77.8,166 -77.7,166 -77.6,166 -77.5,166 -77.4,166 -77.3,166 -77.2,166 -77.1,166 -77))", "dataset_titles": "Impacts of Elevated pCO2 on a Dominant Aragonitic Pteropod (Thecosomata) and its Specialist Predator (Gymnosomata) in the Ross Sea", "datasets": [{"dataset_uid": "600055", "doi": "10.15784/600055", "keywords": "Biota; CO2; Mcmurdo Station; Oceans; Ross Island; Sample/collection Description; Sample/Collection Description; Shell Fish; Southern Ocean", "people": "Seibel, Brad", "repository": "USAP-DC", "science_program": null, "title": "Impacts of Elevated pCO2 on a Dominant Aragonitic Pteropod (Thecosomata) and its Specialist Predator (Gymnosomata) in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600055"}], "date_created": "Sat, 18 Dec 2010 00:00:00 GMT", "description": "Rising atmospheric carbon dioxide concentrations have resulted in greater oceanic uptake of anthropogenic carbon dioxide. Elevated partial pressure of carbon dioxide can impact marine organisms both via decreased carbonate saturation that affects calcification rates and via disturbance to acid-base (metabolic) physiology. Pteropod molluscs (Thecosomata) form shells made of aragonite, a type of calcium carbonate that is highly soluble, suggesting that these organisms may be particularly sensitive to increasing carbon dioxide and reduced carbonate ion concentration. Thecosome pteropods, which dominate the calcium carbonate export south of the Antarctic Polar Front, will be the first major group of marine calcifying organisms to experience carbonate undersaturation within parts of their present-day geographical ranges as a result of anthropogenic carbon dioxide. An unusual, co-evolved relationship between thecosomes and their specialized gymnosome predators provides a unique backdrop against which to assess the physiological and ecological importance of elevated partial pressure of carbon dioxide. Pteropods are functionally important components of the Antarctic ecosystem with potential to influence phytoplankton stocks, carbon export, and dimethyl sulfide levels that, in turn, influence global climate through ocean-atmosphere feedback loops. The research will quantify the impact of elevated carbon dioxide on a dominant aragonitic pteropod, Limacina helicina, and its specialist predator, the gymnosome Clione antarctica, in the Ross Sea through laboratory experimentation. Results will be disseminated broadly to enhance scientific understanding in this field. The project involves collaboration between researchers at a predominantly undergraduate institution with a significant enrollment of students that are typically underrepresented in the research environment (California State University San Marcos - CSUSM) and at a Ph.D.-granting institution (University of Rhode Island - URI). The program will promote education and learning through the joint education of undergraduate students and graduate students at CSUSM and URI as part of a research team, as well as through the teaching activities of the principal investigators. Dr. Keating, CSUSM professor of science education, will participate in the McMurdo fieldwork and lead the outreach opportunities for the project.", "east": 167.0, "geometry": "POINT(166.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Seibel, Brad", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Impacts of Elevated pCO2 on a Dominant Aragonitic Pteropod (Thecosomata) and its Specialist Predator (Gymnosomata) in the Ross Sea", "uid": "p0000694", "west": 166.0}, {"awards": "0439906 Koch, Paul", "bounds_geometry": "POLYGON((162 -72,162.6 -72,163.2 -72,163.8 -72,164.4 -72,165 -72,165.6 -72,166.2 -72,166.8 -72,167.4 -72,168 -72,168 -72.6,168 -73.2,168 -73.8,168 -74.4,168 -75,168 -75.6,168 -76.2,168 -76.8,168 -77.4,168 -78,167.4 -78,166.8 -78,166.2 -78,165.6 -78,165 -78,164.4 -78,163.8 -78,163.2 -78,162.6 -78,162 -78,162 -77.4,162 -76.8,162 -76.2,162 -75.6,162 -75,162 -74.4,162 -73.8,162 -73.2,162 -72.6,162 -72))", "dataset_titles": "Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change", "datasets": [{"dataset_uid": "600041", "doi": "10.15784/600041", "keywords": "Biota; Isotope; Penguin; Ross Sea; Seals; Southern Ocean", "people": "Koch, Paul", "repository": "USAP-DC", "science_program": null, "title": "Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change", "url": "https://www.usap-dc.org/view/dataset/600041"}], "date_created": "Sat, 30 Oct 2010 00:00:00 GMT", "description": "During previous NSF-sponsored research, the PI\u0027s discovered that southern elephant seal colonies once existed along the Victoria Land coast (VLC) of Antarctica, a region where they are no longer observed. Molted seal skin and hair occur along 300 km of coastline, more than 1000 km from any extant colony. The last record of a seal at a former colony site is at ~A.D. 1600. Because abandonment occurred prior to subantarctic sealing, disappearance of the VLC colony probably was due to environmental factors, possibly cooling and encroachment of land-fast, perennial sea ice that made access to haul-out sites difficult. The record of seal inhabitation along the VLC, therefore, has potential as a proxy for climate change. Elephant seals are a predominantly subantarctic species with circumpolar distribution. Genetic studies have revealed significant differentiation among populations, particularly with regard to that at Macquarie I., which is the extant population nearest to the abandoned VLC colony. Not only is the Macquarie population unique genetically, but it is has undergone unexplained decline of 2%/yr over the last 50 years3. In a pilot study, genetic analyses showed a close relationship between the VLC seals and those at Macquarie I. An understanding of the relationship between the two populations, as well as of the environmental pressures that led to the demise of the VLC colonies, will provide a better understanding of present-day population genetic structure, the effect of environmental change on seal populations, and possibly the reasons underlying the modern decline at Macquarie Island.\u003cbr/\u003eThis project addresses several key research problems: (1) Why did elephant seals colonize and then abandon the VLC? (2) What does the elephant seal record reveal about Holocene climate change and sea-ice conditions? (3) What were the foraging strategies of the seals and did these strategies change over time as climate varied? (4) How does the genetic structure of the VLC seals relate to extant populations? (5) How did genetic diversity change over time and with colony decline? (6) Using ancient samples to estimate mtDNA mutation rates, what can be learned about VLC population dynamics over time? (7) What was the ecological relationship between elephant seals and Adelie penguins that occupied the same sites, but apparently at different times? The proposed work includes the professional training of young researchers and incorporation of data into graduate and undergraduate courses.", "east": 168.0, "geometry": "POINT(165 -75)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS", "locations": null, "north": -72.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Earth Sciences", "paleo_time": null, "persons": "Koch, Paul", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change", "uid": "p0000533", "west": 162.0}, {"awards": "0737168 Prentice, Michael; 0541054 Sletten, Ronald", "bounds_geometry": "POLYGON((162.2335 -77.5047,162.3803 -77.5047,162.5271 -77.5047,162.6739 -77.5047,162.8207 -77.5047,162.9675 -77.5047,163.1143 -77.5047,163.2611 -77.5047,163.4079 -77.5047,163.5547 -77.5047,163.7015 -77.5047,163.7015 -77.52814,163.7015 -77.55158,163.7015 -77.57502,163.7015 -77.59846,163.7015 -77.6219,163.7015 -77.64534,163.7015 -77.66878,163.7015 -77.69222,163.7015 -77.71566,163.7015 -77.7391,163.5547 -77.7391,163.4079 -77.7391,163.2611 -77.7391,163.1143 -77.7391,162.9675 -77.7391,162.8207 -77.7391,162.6739 -77.7391,162.5271 -77.7391,162.3803 -77.7391,162.2335 -77.7391,162.2335 -77.71566,162.2335 -77.69222,162.2335 -77.66878,162.2335 -77.64534,162.2335 -77.6219,162.2335 -77.59846,162.2335 -77.57502,162.2335 -77.55158,162.2335 -77.52814,162.2335 -77.5047))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 06 Oct 2010 00:00:00 GMT", "description": "This award supports a project to examine the stratigraphy of near-surface sediments in Taylor Valley, Antarctica. Two contrasting hypotheses have been proposed for surface sediments in lower Taylor Valley, which have important and very different implications for how the West Antarctic Ice Sheet (WAIS) responded to the sea-level rise of the last deglaciation and Holocene environmental changes. One hypothesis holds that the sediments, designated Ross I drift, directly reflect \u003e10,000 14C-years of WAIS shrinkage in the Ross Sea during and perhaps driven by deglacial sea-level rise. The other hypothesis, holds that the Taylor sediments have little significance for WAIS change during the deglaciation. These two hypotheses reflect fundamentally different interpretations of the sediment record. Over the course of two field seasons and a third year at the home institutions, the project will test these two hypotheses using glacial geology, geochemistry, ground penetrating radar (GPR) at both 100 MHz and 400 MHz, and portable sediment coring. The intellectual merit of the proposed work is that it will test these two hypotheses and make novel use of the subsurface record that may result in new insights into WAIS sensitivity during the deglaciation. The study will also directly test the conclusion that Glacial Lake Washburn was much larger than previously proposed during the Last Glacial Maximum (LGM). This occurrence, if real, represents a stunning climate anomaly. Answers to these local ice sheet and lake questions directly pertain to larger scale issues concerning the influences of sea-level rise, climate change, and internal ice-sheet dynamics on the recession of the WAIS since the LGM. There are numerous broader impacts to this project. Understanding the glacial and lake history in the McMurdo Sound region has important implications for the role that the WAIS will play in future sea-level and global climate change. Moreover, the history of Taylor Valley has significance for the ecosystem studies currently being conducted by the LTER group. Lastly, during the course of the proposed research, the project will train two graduate and undergraduate students and the research will be featured prominently in the teaching of students.", "east": 163.7015, "geometry": "POINT(162.9675 -77.6219)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR", "is_usap_dc": false, "keywords": "Not provided; Salt", "locations": null, "north": -77.5047, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Prentice, Michael; Sletten, Ronald S.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.7391, "title": "Collaborative Research: Fluctuations of the West Antarctic Ice Sheet in Relation to Lake History in Taylor Valley, Antarctica, Since the Last Glacial Maximum", "uid": "p0000656", "west": 162.2335}, {"awards": "0636974 Verosub, Kenneth", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 01 Oct 2010 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eThis project performs a paleomagnetic survey of sediment cores from Antarctica\u0027s continental margin. Its goal is to refine the magnetostratigraphy to improve regional stratigraphic correlations, help date cores that lack biostratigraphic indicators, and understand paleoenvironmental conditions and climate change. As well, these cores record the earth\u0027s magnetic field near the magnetic pole, which may offer important information to scientists modeling the geodynamo.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this work include postdoctoral and undergraduate education. There are also implications for society\u0027s understanding of global climate change, since these techniques offer a different perspective on climate change from Antarctic marine sediment cores, which are critical to understanding the behavior of the ice sheets and their links to the global climate.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Verosub, Kenneth", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "New Paleomagnetic and Environmental Magnetic Studies of Old Cores from the Ross Sea Sector, Antarctica", "uid": "p0000367", "west": null}, {"awards": "0538097 Anandakrishnan, Sridhar", "bounds_geometry": "POLYGON((140 -89.8,144 -89.8,148 -89.8,152 -89.8,156 -89.8,160 -89.8,164 -89.8,168 -89.8,172 -89.8,176 -89.8,180 -89.8,180 -89.82,180 -89.84,180 -89.86,180 -89.88,180 -89.9,180 -89.92,180 -89.94,180 -89.96,180 -89.98,180 -90,176 -90,172 -90,168 -90,164 -90,160 -90,156 -90,152 -90,148 -90,144 -90,140 -90,140 -89.98,140 -89.96,140 -89.94,140 -89.92,140 -89.9,140 -89.88,140 -89.86,140 -89.84,140 -89.82,140 -89.8))", "dataset_titles": "IRIS Data Management Center (DMC) holds the full resolution seismic data. Keyword: POLELAKE. Dataset ID: 10-019; seismic data. Keyword: POLELAKE. Dataset ID: 10-019", "datasets": [{"dataset_uid": "000102", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "seismic data. Keyword: POLELAKE. Dataset ID: 10-019", "url": "http://ds.iris.edu/ds/nodes/dmc/"}, {"dataset_uid": "001466", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IRIS Data Management Center (DMC) holds the full resolution seismic data. Keyword: POLELAKE. Dataset ID: 10-019", "url": "http://www.iris.edu/dms/dmc"}], "date_created": "Wed, 08 Sep 2010 00:00:00 GMT", "description": "0538097\u003cbr/\u003eAnandakrishnan\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to intensively study a subglacial Antarctic lake near the geographic South Pole using seismic and radar methods. These ground-based experiments are better suited to determine the presence of water and its thickness than are airborne methods. We hypothesize that there are two end-member explanations for this feature: either the lake is thawed, but freezing on (and likely to have been freezing on through much of the current interglacial period), or it is a frozen, relict lake for which the high basal radar reflectivity is due to intergranular water in a permafrost-like layer beneath the ice. The seismic experiment we propose is ideally suited to examine these alternatives. Intermediate cases of, e.g., a thawed saturated sedimentary base or a smooth crystalline basement layer would also be resolved by this experiment. Seismic reflections are sensitive to changes in acoustic impedance which is strongly variable with fluid content, porosity, and lithology. Water has low density relative to most rocks and low seismic velocity (and nil shear wave velocity) relative to both ice and rock. Thus, discriminating between subglacial water and subglacial rock is a task ideally suited to the seismic reflection technique. This project has significant impacts outside the directly affected fields of Antarctic glaciology and geology. The lake (either thawed or sediments with thin liquid layers around the matrix particles) will have the potential for harboring novel life forms. The experiment has the potential for expanding our information about the newest frontier in life on Earth. The collaboration between PIs in the seismic community and the marine acoustics community will foster cross-disciplinary pollination of ideas, techniques, and tools. In addition to traditional seismic techniques, new methods of data analysis that have been developed by acousticians will be applied to this problem as an independent measure of lake properties. We will train students who will have a wider view of seismology than would be possible in a traditional ocean acoustics or traditional geoscience seismology program of study.", "east": 180.0, "geometry": "POINT(160 -89.9)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e SEISMIC REFLECTION PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS", "is_usap_dc": false, "keywords": "Antarctica; South Pole; Porosity; Not provided; Seismic; Lithology; FIELD INVESTIGATION; Subglacial; Subglacial Lake; FIELD SURVEYS; LABORATORY; Fluid Content; Acoustic Impedance", "locations": "Antarctica; South Pole", "north": -89.8, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Anandakrishnan, Sridhar; Holland, Charles", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -90.0, "title": "Characterization of Lake Amundsen-Scott, S. Pole: A Ground Geophysical Program", "uid": "p0000693", "west": 140.0}, {"awards": "0838842 Passchier, Sandra", "bounds_geometry": "POLYGON((-180 -68,-177 -68,-174 -68,-171 -68,-168 -68,-165 -68,-162 -68,-159 -68,-156 -68,-153 -68,-150 -68,-150 -69,-150 -70,-150 -71,-150 -72,-150 -73,-150 -74,-150 -75,-150 -76,-150 -77,-150 -78,-153 -78,-156 -78,-159 -78,-162 -78,-165 -78,-168 -78,-171 -78,-174 -78,-177 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -77,160 -76,160 -75,160 -74,160 -73,160 -72,160 -71,160 -70,160 -69,160 -68,162 -68,164 -68,166 -68,168 -68,170 -68,172 -68,174 -68,176 -68,178 -68,-180 -68))", "dataset_titles": "Particle-size measurements for diamictites AND-2A sediment core, McMurdo Sound", "datasets": [{"dataset_uid": "601452", "doi": "10.15784/601452", "keywords": "Antarctica; McMurdo Sound; Miocene; Particle Size; Pleistocene; Pliocene", "people": "Hansen, Melissa A.; Passchier, Sandra", "repository": "USAP-DC", "science_program": "ANDRILL", "title": "Particle-size measurements for diamictites AND-2A sediment core, McMurdo Sound", "url": "https://www.usap-dc.org/view/dataset/601452"}], "date_created": "Fri, 27 Aug 2010 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The project aims on studying sediment cores collected from Prydz Bay and the Ross Sea to unravel the Neogene paleoclimatic history of the East Antarctic ice sheet. In the light of current measurements and predictions of a substantial rise in global temperature, investigations into the sensitivity of the East Antarctic ice sheet to climate change and its role in the climate system are essential. Geological records of former periods of climate change provide an opportunity to ground truth model predictions. The scientific objective of this project is to identify a previously proposed middle Miocene transition from a more dynamic wet-based East Antarctic ice sheet to the present semi-permanent ice sheet that is partially frozen to its bed. The timing and significance of this transition is controversial due to a lack of quantitative studies on well-dated ice-proximal sedimentary sequences. This project partially fills that gap using the composition and physical properties of diamictites and sandstones to establish shifts in ice-sheet drainage pathways, paleoenvironments and basal ice conditions. The results from the two key areas around the Antarctic continental margin will provide insight into the behavior of the East Antarctic ice sheet across the middle Miocene transition and through known times of warming in the late Miocene and Pliocene.", "east": -150.0, "geometry": "POINT(-175 -73)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -68.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Passchier, Sandra", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Determining Middle Miocene through Pliocene Changes in Paleo Ice-flow and Basal Ice Conditions in East Antarctica through Sedimentological Analyses of Core Samples", "uid": "p0000147", "west": 160.0}, {"awards": "0537143 Blanchette, Robert", "bounds_geometry": "POLYGON((-69 -60,-68.3 -60,-67.6 -60,-66.9 -60,-66.2 -60,-65.5 -60,-64.8 -60,-64.1 -60,-63.4 -60,-62.7 -60,-62 -60,-62 -61,-62 -62,-62 -63,-62 -64,-62 -65,-62 -66,-62 -67,-62 -68,-62 -69,-62 -70,-62.7 -70,-63.4 -70,-64.1 -70,-64.8 -70,-65.5 -70,-66.2 -70,-66.9 -70,-67.6 -70,-68.3 -70,-69 -70,-69 -69,-69 -68,-69 -67,-69 -66,-69 -65,-69 -64,-69 -63,-69 -62,-69 -61,-69 -60))", "dataset_titles": "(Arenz et al. 2006) DQ317323, DQ317324, DQ317325, DQ317326, DQ317327, DQ317328, DQ317329, DQ317330, DQ317331, DQ317332, DQ317333, DQ317334, DQ317335, DQ317336, DQ317337, DQ317338, DQ317339, DQ317340, DQ317341, DQ317342, DQ317343, DQ317344, DQ317345, DQ317346, DQ317347, DQ317348, DQ317349, DQ317350, DQ317351, DQ317352, DQ317353, DQ317354, DQ317355, DQ317356, DQ317357, DQ317358, DQ317359, DQ317360, DQ317361, DQ317362, DQ317363, DQ317364, DQ317365, DQ317366, DQ317367, DQ317368, DQ317369, DQ317370, DQ317371, DQ317372, DQ317373, DQ317374, DQ317375, DQ317376, DQ317377, DQ317378, DQ317379, DQ317380, DQ317381, DQ317382, DQ317383, DQ317384, DQ317385, DQ317386, DQ317387, DQ317388, DQ317389 (Arenz and Blanchette 2009) FJ235934, FJ235935, FJ235936, FJ235937, FJ235938, FJ235939, FJ235940, FJ235941, FJ235942, FJ235943, FJ235944, FJ235945, FJ235946, FJ235947, FJ235948, FJ235949, FJ235950, FJ235951, FJ235952, FJ235953, FJ235954, FJ235955, FJ235956, FJ235957, FJ235958, FJ235959, FJ235960, FJ235961, FJ235962, FJ235963, FJ235964, FJ235965, FJ235966, FJ235967, FJ235968, FJ235969, FJ235970, FJ235971, FJ235972, FJ235973, FJ235974, FJ235975, FJ235976, FJ235977, FJ235978, FJ235979, FJ235980, FJ235981, FJ235982, FJ235983, FJ235984, FJ235985, FJ235986, FJ235987, FJ235988, FJ235989, FJ235990, FJ235991, FJ235992, FJ235993, FJ235994, FJ235995, FJ235996, FJ235997, FJ235998, FJ235999, FJ236000, FJ236001, FJ236002, FJ236003, FJ236004, FJ236005, FJ236006, FJ236007, FJ236008, FJ236009, FJ236010, FJ236011, FJ236012, FJ236013, FJ236014 (Blanchette et al. 2010) GU212367, GU212368, GU212369, GU212370, GU212371, GU212372, GU212373, GU212374, GU212375, GU212376, GU212377, GU212378, GU212379, GU212380, GU212381, GU212382, GU212383, GU212384, GU212385, GU212386, GU212387, GU212388, GU212389, GU212390, GU212391, GU212392, GU212393, GU212394, GU212395, GU212396, GU212397, GU212398, GU212399, GU212400, GU212401, GU212402, GU212403, GU212404, GU212405, GU212406, GU212407, GU212408, GU212409, GU212410, GU212411, GU212412, GU212413, GU212414, GU212415, GU212416, GU212417, GU212418, GU212419, GU212420, GU212421, GU212422, GU212423, GU212424, GU212425, GU212426, GU212427, GU212428, GU212429, GU212430, GU212431, GU212432, GU212433, GU212434", "datasets": [{"dataset_uid": "000121", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "(Arenz et al. 2006) DQ317323, DQ317324, DQ317325, DQ317326, DQ317327, DQ317328, DQ317329, DQ317330, DQ317331, DQ317332, DQ317333, DQ317334, DQ317335, DQ317336, DQ317337, DQ317338, DQ317339, DQ317340, DQ317341, DQ317342, DQ317343, DQ317344, DQ317345, DQ317346, DQ317347, DQ317348, DQ317349, DQ317350, DQ317351, DQ317352, DQ317353, DQ317354, DQ317355, DQ317356, DQ317357, DQ317358, DQ317359, DQ317360, DQ317361, DQ317362, DQ317363, DQ317364, DQ317365, DQ317366, DQ317367, DQ317368, DQ317369, DQ317370, DQ317371, DQ317372, DQ317373, DQ317374, DQ317375, DQ317376, DQ317377, DQ317378, DQ317379, DQ317380, DQ317381, DQ317382, DQ317383, DQ317384, DQ317385, DQ317386, DQ317387, DQ317388, DQ317389 (Arenz and Blanchette 2009) FJ235934, FJ235935, FJ235936, FJ235937, FJ235938, FJ235939, FJ235940, FJ235941, FJ235942, FJ235943, FJ235944, FJ235945, FJ235946, FJ235947, FJ235948, FJ235949, FJ235950, FJ235951, FJ235952, FJ235953, FJ235954, FJ235955, FJ235956, FJ235957, FJ235958, FJ235959, FJ235960, FJ235961, FJ235962, FJ235963, FJ235964, FJ235965, FJ235966, FJ235967, FJ235968, FJ235969, FJ235970, FJ235971, FJ235972, FJ235973, FJ235974, FJ235975, FJ235976, FJ235977, FJ235978, FJ235979, FJ235980, FJ235981, FJ235982, FJ235983, FJ235984, FJ235985, FJ235986, FJ235987, FJ235988, FJ235989, FJ235990, FJ235991, FJ235992, FJ235993, FJ235994, FJ235995, FJ235996, FJ235997, FJ235998, FJ235999, FJ236000, FJ236001, FJ236002, FJ236003, FJ236004, FJ236005, FJ236006, FJ236007, FJ236008, FJ236009, FJ236010, FJ236011, FJ236012, FJ236013, FJ236014 (Blanchette et al. 2010) GU212367, GU212368, GU212369, GU212370, GU212371, GU212372, GU212373, GU212374, GU212375, GU212376, GU212377, GU212378, GU212379, GU212380, GU212381, GU212382, GU212383, GU212384, GU212385, GU212386, GU212387, GU212388, GU212389, GU212390, GU212391, GU212392, GU212393, GU212394, GU212395, GU212396, GU212397, GU212398, GU212399, GU212400, GU212401, GU212402, GU212403, GU212404, GU212405, GU212406, GU212407, GU212408, GU212409, GU212410, GU212411, GU212412, GU212413, GU212414, GU212415, GU212416, GU212417, GU212418, GU212419, GU212420, GU212421, GU212422, GU212423, GU212424, GU212425, GU212426, GU212427, GU212428, GU212429, GU212430, GU212431, GU212432, GU212433, GU212434", "url": "http://www.ncbi.nlm.nih.gov/genbank/"}], "date_created": "Mon, 24 May 2010 00:00:00 GMT", "description": "Fungi in Antarctic ecosystems are major contributors to biodiversity and have great influence on many processes such as biodegradation and nutrient cycling. It is essential for biological surveys as well as genomic and proteomic studies to be completed so a better understanding of these organisms is obtained. Previous research has identified unique fungi associated with historic wooden structures brought to Antarctica by Robert F. Scott and Ernest Shackleton during the Heroic Era of exploration. Many of the fungi found are previously undescribed species that belong to the little known genus Cadophora. The research team will obtain important new information on the fungi present in the Ross Sea and Peninsula Regions of Antarctica, particularly their role in decomposition and nutrient recycling and their mechanisms and strategies for survival in the polar environment. New tools and methods include denaturing gradient gel electrophoresis (DGGE), real-time PCR, and proteomic profiling. These analyses will reveal key details of the physiological adaptations these fungi have evolved to carry out processes such as biodegradation and nutrient cycling under conditions that would inhibit other fungi. This work, coupled with the training and learning opportunities it provides, will be of value to many fields of study including microbial ecology, polar biology, wood microbiology, environmental science, soil science, geobiochemistry, and mycology as well as fungal phylogenetics, proteomics and genomics. Results obtained will have immediate applied use to help preserve and protect Antarctica\u0027s historic monuments. The investigations proposed are a continuation of research to identify the microbes attacking these historic structures and artifacts and to elucidate their biology and ecology in the polar environment. New research will also be done at the historic Cape Adare huts, the first wooden structures to be built in Antarctica and also at East Base, an American historic site on Stonington Island from the Admiral Byrd and Ronne Expeditions of 1939-1948. The research team will conduct vital studies needed to successfully conserve the wooden structures and artifacts at these sites and protect them for future generations", "east": -62.0, "geometry": "POINT(-65.5 -65)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Blanchette, Robert", "platforms": "Not provided", "repo": "NCBI GenBank", "repositories": "NCBI GenBank", "science_programs": null, "south": -70.0, "title": "Studies of Antarctic Fungi: Adaptive Stratigies for Survival and Protecting Antarctica\u0027s Historic Structures", "uid": "p0000187", "west": -69.0}, {"awards": "0338151 Raymond, Charles", "bounds_geometry": "POINT(-112.086 -79.468)", "dataset_titles": "Englacial Layers and Attenuation Rates across the Ross and Amundsen Sea Ice-Flow Divide (WAIS Divide), West Antarctica; Surface Elevation and Ice Thickness, Western Marie Byrd Land, Antarctica", "datasets": [{"dataset_uid": "609470", "doi": "10.7265/N5416V0W", "keywords": "Airborne Radar; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Radar; WAIS Divide", "people": "Raymond, Charles; Matsuoka, Kenichi", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Englacial Layers and Attenuation Rates across the Ross and Amundsen Sea Ice-Flow Divide (WAIS Divide), West Antarctica", "url": "https://www.usap-dc.org/view/dataset/609470"}, {"dataset_uid": "609119", "doi": "10.7265/N5BZ63ZH", "keywords": "Airborne Radar; Airplane; Antarctica; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marie Byrd Land", "people": "Wilson, Douglas S.; Luyendyk, Bruce P.", "repository": "USAP-DC", "science_program": null, "title": "Surface Elevation and Ice Thickness, Western Marie Byrd Land, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609119"}], "date_created": "Tue, 11 May 2010 00:00:00 GMT", "description": "This award supports an investigation of spatial variations of ice temperature and subglacial conditions using available ice-penetrating radar data around a future deep ice coring site near the Ross and Amundsen flow divide of West Antarctic Ice Sheet. Besides geometry of reflection layers the focus will be on intensities of radar echoes from within ice deeper than several hundred meters and will also examine echoes from the bed. Preliminary studies on theory and comparison with Japanese radar data from East Antarctica suggest that large spatial variations of the vertical gradient of radar echoes from within ice exist and are caused primarily by ice temperature and secondarily by crystal-orientation fabric. The hypothesis that the vertical gradient is a proxy of ice temperature will be tested. The project will utilize an existing data set from the Support Office for Aerogeophysical Research in Antarctica (SOAR) and will complement work already underway at University of Texas to analyze the radar data. The project will provide undergraduate research experience with an emphasis on computer analysis of time series and large data sets as well as development of web-based resource of results and methods and will support an international collaboration between US and Japan through discussions on the preliminary results from their study sites. Practical procedures developed through this study will be downloadable from the project\u0027s web site in the third year and will allow investigation of other ice sheets using existing radar data sets. This project will contribute to the interpretation of the future inland West Antarctic ice core and will help in the understanding of ice sheet history and climate change.", "east": -112.086, "geometry": "POINT(-112.086 -79.468)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e ALTIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LASERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e RADAR ALTIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR", "is_usap_dc": true, "keywords": "SOAR; Ice Sheet Elevation; Antarctic Ice Sheet; Layers; USAP-DC; West Antarctic; FIELD INVESTIGATION; Amundsen; Ice Sheet; Airborne Laser Altimetry; Ice Surface; Not provided; Ice Penetrating Radar; Ice Sheet Thickness; Ice Extent; Ice Surface Elevation; Ice Cover; Ice Deformation; FIELD SURVEYS; Antarctica; Ground Ice; Subglacial; Reflection Layers; West Antarctic Ice Sheet; Ice Surface Temperature; LABORATORY; Amundsen Flow Divide; Radar Echo Sounding; Internal Layering; Radar Altimetry; Ice; Radar Echoes; Englacial; Crystal Orientation Fabric; Ice Thickness; Altimetry; Ice Temperature; Radar Echo Sounder; Ice Thickness Distribution", "locations": "Antarctic Ice Sheet; Antarctica; West Antarctic; Amundsen; Amundsen Flow Divide; West Antarctic Ice Sheet", "north": -79.468, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Raymond, Charles; Matsuoka, Kenichi; Luyendyk, Bruce P.; Wilson, Douglas S.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.468, "title": "Glaciological Characteristics of the Ross/Amundsen Sea Ice-flow Divide Deduced by a New Analysis of Ice-penetrating Radar Data", "uid": "p0000017", "west": -112.086}, {"awards": "0126279 Lawver, Lawrence; 0125624 Wilson, Terry", "bounds_geometry": "POLYGON((163.69456 -75.04911,164.525266 -75.04911,165.355972 -75.04911,166.186678 -75.04911,167.017384 -75.04911,167.84809 -75.04911,168.678796 -75.04911,169.509502 -75.04911,170.340208 -75.04911,171.170914 -75.04911,172.00162 -75.04911,172.00162 -75.3293,172.00162 -75.60949,172.00162 -75.88968,172.00162 -76.16987,172.00162 -76.45006,172.00162 -76.73025,172.00162 -77.01044,172.00162 -77.29063,172.00162 -77.57082,172.00162 -77.85101,171.170914 -77.85101,170.340208 -77.85101,169.509502 -77.85101,168.678796 -77.85101,167.84809 -77.85101,167.017384 -77.85101,166.186678 -77.85101,165.355972 -77.85101,164.525266 -77.85101,163.69456 -77.85101,163.69456 -77.57082,163.69456 -77.29063,163.69456 -77.01044,163.69456 -76.73025,163.69456 -76.45006,163.69456 -76.16987,163.69456 -75.88968,163.69456 -75.60949,163.69456 -75.3293,163.69456 -75.04911))", "dataset_titles": "Expedition Data; NBP0401 data", "datasets": [{"dataset_uid": "001664", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0401"}, {"dataset_uid": "000106", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0401 data", "url": "https://www.rvdata.us/search/cruise/NBP0401"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a study to investigate the tectonic development of the southwestern Ross Sea region. Displacements between East and West Antarctica have long been proposed based on global plate circuits, apparent hot spot motions, interpretations of seafloor magnetic anomalies, paleomagnetism, and on geologic grounds. Such motions require plate boundaries crossing Antarctica, yet these boundaries have never been explicitly defined. This project will attempt to delineate the late Cenozoic - active boundary between East and West Antarctica along the Terror Rift in the western Ross Sea, where young structures have been identified, continuity between active extension and intracontinental structures can be established, and where accessibility via ship will allow new key data sets to be acquired. We will use multi-source marine and airborne geophysical data to map the fault patterns and volcanic structure along the eastern margin of the Terror Rift. The orientations of volcanic fissures and seamount alignments on the seafloor will be mapped using multibeam bathymetry. The volcanic alignments will show the regional extension or shear directions across the Terror Rift and the orientations of associated crustal stresses. Swath bathymetry and single channel seismic data will be used to document neotectonic fault patterns and the eastern limit of recent faulting. Delineation of neotectonic fault patterns will demonstrate whether the eastern margin of the Terror Rift forms a continuous boundary and whether the rift itself can be linked with postulated strike-slip faults in the northwestern Ross Sea. Seafloor findings from this project will be combined with fault kinematic and stress field determinations from the surrounding volcanic islands and the Transantarctic Mountains. The integrated results will test the propositions that the eastern boundary of the Terror Rift forms the limit of the major, late Cenozoic -active structures through the Ross Sea and that Terror Rift kinematics involve dextral transtension linked to the right-lateral strike-slip faulting to the north. These results will help constrain the kinematic and dynamic links between the West Antarctic rift system and Southern Ocean structures and any related motions between East and West Antarctica. In the first year, a collaborative structural analysis of existing multichannel and single channel seismic profiles and aeromagnetic data over the Terror Rift will be conducted. The location of volcanic vents or fissures and any fault scarps on the sea floor will be identified and a preliminary interpretation of the age and kinematics of deformation in the Terror Rift will be produced. Late in the second year, a one-month cruise on RVIB N.B. Palmer will carry out multibeam bathymetric and sidescan sonar mapping of selected portions of the seafloor of Terror Rift. Gravity, magnetics, seismic reflection and Bathy2000 3.5 kHz sub-bottom profile data will also be collected across the rift. In the third year, we will use these multisource data to map the orientations and forms of volcanic bodies and the extent and geometry of neotectonic faulting associated with the Terror Rift. The project will: 1) complete a map of neotectonic faults and volcanic structures in the Terror Rift; 2) interpret the structural pattern to derive the motions and stresses associated with development of the rift; 3) compare Terror Rift structures with faults and lineaments mapped in the Transantarctic Mountains to improve age constraints on the structures; and 4) integrate the late Cenozoic structural interpretations from the western Ross Sea with Southern Ocean plate boundary kinematics.", "east": 172.00162, "geometry": "POINT(167.84809 -76.45006)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": true, "keywords": "R/V NBP", "locations": null, "north": -75.04911, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Wilson, Terry", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.85101, "title": "Collaborative Research: Neotectonic Structure of Terror Rift, Western Ross Sea", "uid": "p0000111", "west": 163.69456}, {"awards": "0444134 Mitchell, B. Gregory", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0606", "datasets": [{"dataset_uid": "002646", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0606", "url": "https://www.rvdata.us/search/cruise/NBP0606"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The Shackleton Fracture Zone (SFZ) in Drake Passage of the Southern Ocean defines a boundary between low and high phytoplankton waters. Low chlorophyll water flowing through the southern Drake Passage emerges as high chlorophyll water to the east, and recent evidence indicates that the Southern Antarctic Circumpolar Current Front (SACCF) is steered south of the SFZ onto the Antarctic Peninsula shelf where mixing between the water types occurs. The mixed water is then advected off-shelf with elevated iron and phytoplankton biomass. The SFZ is therefore an ideal natural laboratory to improve the understanding of plankton community responses to natural iron fertilization, and how these processes influence export of organic carbon to the ocean interior. The bathymetry of the region is hypothesized to influence mesoscale circulation and transport of iron, leading to the observed patterns in phytoplankton biomass. The position of the Antarctic Circumpolar Current (ACC) is further hypothesized to influence the magnitude of the flow of ACC water onto the peninsula shelf, mediating the amount of iron transported into the Scotia Sea. To address these hypotheses, a research cruise will be conducted near the SFZ and to the east in the southern Scotia Sea. A mesoscale station grid for vertical profiles, water sampling, and bottle incubation enrichment experiments will complement rapid surface surveys of chemical, plankton, and hydrographic properties. Distributions of manganese, aluminum and radium isotopes will be determined to trace iron sources and estimate mixing rates. Phytoplankton and bacterial physiological states (including responses to iron enrichment) and the structure of the plankton communities will be studied. The primary goal is to better understand how plankton productivity, community structure and export production in the Southern Ocean are affected by the coupling between bathymetry, mesoscale circulation, and distributions of limiting nutrients. The proposed work represents an interdisciplinary approach to address the fundamental physical, chemical and biological processes that contribute to the abrupt transition in chl-a which occurs near the SFZ. Given recent indications that the Southern Ocean is warming, it is important to advance the understanding of conditions that regulate the present ecosystem structure in order to predict the effects of climate variability. This project will promote training and learning across a broad spectrum of groups. Funds are included to support postdocs, graduate students, and undergraduates. In addition, this project will contribute to the development of content for the Polar Science Station website, which has been a resource since 2001 for instructors and students in adult education, home schooling, tribal schools, corrections education, family literacy programs, and the general public.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Mitchell, B.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Plankton Community Structure and Iron Distribution in the Southern Drake Passage and Scotia Sea", "uid": "p0000837", "west": null}, {"awards": "0125526 Wise, Sherwood", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0602A", "datasets": [{"dataset_uid": "002616", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0602A", "url": "https://www.rvdata.us/search/cruise/NBP0602A"}, {"dataset_uid": "001571", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0602A"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this \"demonstration cruise\" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the \"Greenhouse-Icehouse\" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program\u0027s technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the \"no man\u0027s land\" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program\u0027s vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this \"demonstration cruise\" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the \"Greenhouse-Icehouse\" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program\u0027s technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the \"no man\u0027s land\" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program\u0027s vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ROCK CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, John", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Proposal: SHALDRIL - A Demonstration Drilling Cruise to the James Ross Basin", "uid": "p0000828", "west": null}, {"awards": "9714299 Caron, David", "bounds_geometry": "POLYGON((-179.9984 -43.56676,-143.99865 -43.56676,-107.9989 -43.56676,-71.99915 -43.56676,-35.9994 -43.56676,0.000349999999997 -43.56676,36.0001 -43.56676,71.99985 -43.56676,107.9996 -43.56676,143.99935 -43.56676,179.9991 -43.56676,179.9991 -47.057693,179.9991 -50.548626,179.9991 -54.039559,179.9991 -57.530492,179.9991 -61.021425,179.9991 -64.512358,179.9991 -68.003291,179.9991 -71.494224,179.9991 -74.985157,179.9991 -78.47609,143.99935 -78.47609,107.9996 -78.47609,71.99985 -78.47609,36.0001 -78.47609,0.000349999999997 -78.47609,-35.9994 -78.47609,-71.99915 -78.47609,-107.9989 -78.47609,-143.99865 -78.47609,-179.9984 -78.47609,-179.9984 -74.985157,-179.9984 -71.494224,-179.9984 -68.003291,-179.9984 -64.512358,-179.9984 -61.021425,-179.9984 -57.530492,-179.9984 -54.039559,-179.9984 -50.548626,-179.9984 -47.057693,-179.9984 -43.56676))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002003", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9901"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "*** Caron 9714299 The analysis of microbial biodiversity of extreme environments is difficult because traditional methods for examining diversity are often ineffective for assessing species richness within these communities. Additional difficulties arise due to the difficulties of recreating and maintaining pertinent environmental features during sample collection and procession. This study focuses on the protistan assemblages (algae and protozoa) in the sea ice, sediment and ocean environments of the Ross Sea, Antarctica. The identification of protistan species in natural assemblages traditionally has entailed direct microscopical analyses as well as enrichment and culture techniques for assessing biodiversity. Determination of diversity for these assemblages in therefore susceptible to biases as a consequence of sampling, enrichment and culture, as well as selective losses due to sample preservation and concentration for microscopy. The goals of this project are: (1) to develop and apply molecular biological approaches to assess species diversity of small protists (algae and protozoa smaller than 100 micrometers) in ocean water, sea ice and sediment environments and (2) to obtain baseline physiological information on the growth rates, feeding rates and growth efficiencies of cultured protozoa under pertinent temperature regimes. Molecular biological studies will involve the use of PCR-based protocols to examine small subunit ribosomal RNA gene (srDNA) diversity. Approaches and techniques developed will be applicable to any other water body or sediment and would provide a means to examine the representativeness of protistan cultures in extant culture collections. ***", "east": 179.9991, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56676, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Caron, David; Jeffries, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.47609, "title": "LEXEN: Protistan Biodiversity in Antarctic Marine Ecosystems: Molecular Biological and Traditional Approaches", "uid": "p0000625", "west": -179.9984}, {"awards": "0087401 Smith, Walker", "bounds_geometry": null, "dataset_titles": "Current Meter Data from the Ross Sea acquired with a Mooring deployed in December 2005 and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006); Expedition data of NBP0301B; Expedition data of NBP0305A; Expedition data of NBP0501; Expedition data of NBP0601A; Fluorometer Data acquired on Moorings deployed the Ross Sea and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006); Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601A", "datasets": [{"dataset_uid": "002623", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0601A", "url": "https://www.rvdata.us/search/cruise/NBP0601A"}, {"dataset_uid": "002621", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0305A", "url": "https://www.rvdata.us/search/cruise/NBP0305A"}, {"dataset_uid": "601341", "doi": null, "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Fluid Chemistry Data; Mooring; NBP0601A; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Seawater Measurements; Southern Ocean", "people": "Asper, Vernon; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601A", "url": "https://www.usap-dc.org/view/dataset/601341"}, {"dataset_uid": "601339", "doi": null, "keywords": "Antarctica; Current Meter; Mooring; NBP0601A; Oceans; Physical Oceanography; Ross Sea; Southern Ocean", "people": "Smith, Walker; Asper, Vernon", "repository": "USAP-DC", "science_program": null, "title": "Current Meter Data from the Ross Sea acquired with a Mooring deployed in December 2005 and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006)", "url": "https://www.usap-dc.org/view/dataset/601339"}, {"dataset_uid": "002622", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "601333", "doi": null, "keywords": "Antarctica; Flourometer; Mooring; NBP0601A; Ross Sea; Southern Ocean", "people": "Asper, Vernon; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Fluorometer Data acquired on Moorings deployed the Ross Sea and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006)", "url": "https://www.usap-dc.org/view/dataset/601333"}, {"dataset_uid": "002583", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0301B", "url": "https://www.rvdata.us/search/cruise/NBP0301B"}, {"dataset_uid": "002627", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "During the past few decades of oceanographic research, it has been recognized that significant variations in biogeochemical processes occur among years. Interannual variations in the Southern Ocean are known to occur in ice extent and concentration, in the composition of herbivore communities, and in bird and marine mammal distributions and reproductive success. However, little is known about the interannual variations in production of phytoplankton or the role that these variations play in the food web. This project will collect time series data on the seasonal production of phytoplankton in the southern Ross Sea, Antarctica. Furthermore, it will assess the interannual variations of the production of the two major functional groups of the system, diatoms and Phaeocystis Antarctica, a colonial haptophyte. The Ross Sea provides a unique setting for this type of investigation for a number of reasons. For example, a de facto time-series has already been initiated in the Ross Sea through the concentration of a number of programs in the past ten years. It also is well known that the species diversity is reduced relative to other systems and its seasonal production is as great as anywhere in the Antarctic. Most importantly, seasonal production of both the total phytoplankton community (as well as its two functional groups) can be estimated from late summer nutrient profiles. The project will involve short cruises on the US Coast Guard ice breakers in the southern Ross Sea that will allow the collection of water column nutrient and particulate after data at specific locations in the late summer of each of five years. Additionally, two moorings with in situ nitrate analyzers moored at fifteen will be deployed, thus collecting for the first time in the in the Antarctic a time-series of euphotic zone nutrient concentrations over the entire growing season. All nutrient data will be used to calculate seasonal production for each year in the southern Ross Sea and compared to previously collected information, thereby providing an assessment of interannual variations in net community production. Particulate matter data will allow us to estimate the amount of export from the surface layer by late summer, and therefore calculate the interannual variability of this ecosystem process. Interannual variations of seasonal production (and of the major taxa of producers) are a potentially significant feature in the growth and survival of higher trophic levels within the food web of the Ross Sea. They are also important in order to understand the natural variability in biogeochemical processes of the region. Because polar regions such as the Ross Sea are predicted to be impacted by future climate change, biological changes are also anticipated. Placing these changes in the context of natural variability is an essential element of understanding and predicting such alterations. This research thus seeks to quantify the natural variability of an Antarctic coastal system, and ultimately understand its causes and impacts on food webs and biogeochemical cycles of the Ross Sea.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "Ross Sea; AMD; USAP-DC; Amd/Us; USA/NSF; R/V NBP", "locations": "Ross Sea", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker; Gordon, Arnold", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Interannual Variability in the Antarctic-Ross Sea (IVARS): Nutrients and Seasonal Production", "uid": "p0000803", "west": null}, {"awards": "9632763 Smith, Raymond; 9011927 Ross, Robin", "bounds_geometry": "POLYGON((-79.68459 -52.36474,-77.851019 -52.36474,-76.017448 -52.36474,-74.183877 -52.36474,-72.350306 -52.36474,-70.516735 -52.36474,-68.683164 -52.36474,-66.849593 -52.36474,-65.016022 -52.36474,-63.182451 -52.36474,-61.34888 -52.36474,-61.34888 -54.071087,-61.34888 -55.777434,-61.34888 -57.483781,-61.34888 -59.190128,-61.34888 -60.896475,-61.34888 -62.602822,-61.34888 -64.309169,-61.34888 -66.015516,-61.34888 -67.721863,-61.34888 -69.42821,-63.182451 -69.42821,-65.016022 -69.42821,-66.849593 -69.42821,-68.683164 -69.42821,-70.516735 -69.42821,-72.350306 -69.42821,-74.183877 -69.42821,-76.017448 -69.42821,-77.851019 -69.42821,-79.68459 -69.42821,-79.68459 -67.721863,-79.68459 -66.015516,-79.68459 -64.309169,-79.68459 -62.602822,-79.68459 -60.896475,-79.68459 -59.190128,-79.68459 -57.483781,-79.68459 -55.777434,-79.68459 -54.071087,-79.68459 -52.36474))", "dataset_titles": "Expedition Data; Expedition data of NBP0105", "datasets": [{"dataset_uid": "001649", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0301"}, {"dataset_uid": "001998", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0001"}, {"dataset_uid": "002605", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0105", "url": "https://www.rvdata.us/search/cruise/NBP0105"}, {"dataset_uid": "001488", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0901"}, {"dataset_uid": "002292", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9302"}, {"dataset_uid": "001665", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0401"}, {"dataset_uid": "001613", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0501"}, {"dataset_uid": "001817", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0201"}, {"dataset_uid": "001884", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0101"}, {"dataset_uid": "001578", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0601"}, {"dataset_uid": "002045", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9906"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The annual advance and retreat of pack ice may be the major physical determinant of spatial and temporal changes in the structure and function of antarctic marine communities. Interannual cycles and/or trends in the annual extent of pack ice may also have significant effects on all levels of the food web, from total annual primary production to breeding success in seabirds. Historical records indicate a six to eight year cycle in the maximum extent of pack ice in the winter. During this decade, winters were colder in 1980 and 1981, and again in 1986 and 1987. Winter-over survival in Adelie penguins varied on the same cycle, higher in winters with heavy pack ice. This Long Term Ecological Research (LTER) project will define ecological processes linking the extent of annual pack ice with the biological dynamics of different trophic levels within antarctic marine communities. The general focus is on interannual variability in representative populations from the antarctic marine food web and on mechanistic linkages that control the observed variability in order to develop broader generalizations applicable to other large marine environments. To achieve these objectives, data from several spatial and temporal scales, including remote sensing, a field approach that includes an annual monitoring program, a series of process-oriented research cruises, and a modeling effort to provide linkages on multiple spatial and temporal scales between biological and environmental components of the ecosystem will be employed.", "east": -61.34888, "geometry": "POINT(-70.516735 -60.896475)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V LMG; R/V NBP", "locations": null, "north": -52.36474, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Raymond; Ross, Robin Macurda; Fraser, William; Martinson, Douglas; Ducklow, Hugh", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": "LTER", "south": -69.42821, "title": "Long-Term Ecological Research on the Antarctic Marine Ecosystem: An Ice-Dominated Environment", "uid": "p0000236", "west": -79.68459}, {"awards": "0094078 Bart, Philip", "bounds_geometry": "POLYGON((-179.99992 -72.00044,-143.999984 -72.00044,-108.000048 -72.00044,-72.000112 -72.00044,-36.000176 -72.00044,-0.000239999999991 -72.00044,35.999696 -72.00044,71.999632 -72.00044,107.999568 -72.00044,143.999504 -72.00044,179.99944 -72.00044,179.99944 -72.574101,179.99944 -73.147762,179.99944 -73.721423,179.99944 -74.295084,179.99944 -74.868745,179.99944 -75.442406,179.99944 -76.016067,179.99944 -76.589728,179.99944 -77.163389,179.99944 -77.73705,143.999504 -77.73705,107.999568 -77.73705,71.999632 -77.73705,35.999696 -77.73705,-0.000240000000019 -77.73705,-36.000176 -77.73705,-72.000112 -77.73705,-108.000048 -77.73705,-143.999984 -77.73705,-179.99992 -77.73705,-179.99992 -77.163389,-179.99992 -76.589728,-179.99992 -76.016067,-179.99992 -75.442406,-179.99992 -74.868745,-179.99992 -74.295084,-179.99992 -73.721423,-179.99992 -73.147762,-179.99992 -72.574101,-179.99992 -72.00044))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001648", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0301A"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "PROPOSAL NO.: 0094078\u003cbr/\u003ePRINCIPAL INVESTIGATOR: Bart, Philip\u003cbr/\u003eINSTITUTION NAME: Louisiana State University \u0026 Agricultural and Mechanical College\u003cbr/\u003eTITLE: CAREER: Relative frequency and phase of extreme expansions of the Antarctic Ice Sheets during the late Neogene\u003cbr/\u003eNSF RECEIVED DATE: 07/27/2000\u003cbr/\u003e\u003cbr/\u003ePROJECT SUMMARY\u003cbr/\u003e\u003cbr/\u003eExpansions and contractions of the Antarctic Ice Sheets (AISs) have undoubtedly had a profound influence on Earth\u0027s climate and global sea-level. However, rather than being a single entity, the Antarctic cryosphere consists of three primary elements: 1) the East Antarctic Ice Sheet (EAIS); 2) the West Antarctic Ice Sheet (WAIS); and 3) the Antarctic Peninsula Ice Cap (APIC). The distinguishing characteristics include significant differences in: 1) ice volume; 2) substratum elevation; 3) ice-surface elevation; and 4) location with respect to latitude. Various lines of evidence indicate that the AISs have undergone significant fluctuations in the past and that fluctuations will continue to occur in the future. The exact nature of the fluctuations has been the subject of many lively debates. According to one line of reasoning, the land-based EAIS has been relatively stable, experiencing only minor fluctuations since forming in the middle Miocene, whereas the marine-based WAIS has been dynamic, waxing and waning frequently since the late Miocene. According to an alternate hypothesis, the ice sheets advanced and retreated synchronously. These two views are incompatible. \u003cbr/\u003e\u003cbr/\u003eThe first objective of this proposal is to compare the long-term past behavior of the WAIS to that of the EAIS and APIC. The fluctuations of the AISs involve many aspects (the frequency of changes, the overall magnitude of ice-volume change, etc.), and the activities proposed here specifically concern the frequency and phase of extreme advances of the ice sheet to the continental shelf. The project will build upon previous seismic-stratigraphic investigations of the continental shelves. These studies have clarified many issues concerning the minimum frequency of extreme expansions for the individual ice sheets, but some important questions remain. During the course of the project, the following questions will be evaluated.\u003cbr/\u003e\u003cbr/\u003eQuestion 1) Were extreme advances of the EAIS and WAIS across the shelf of a similar frequency and coeval? This evaluation is possible because the western Ross Sea continental shelf (Northern Basin) receives drainage from the EAIS, and the eastern Ross Sea (Eastern Basin) receives drainage from the WAIS. Quantitative analyses of the extreme advances from these two areas have been conducted by Alonso et al. (1992) and Bart et al. (2000), respectively. However, the existing single-channel seismic grids are incomplete and can not be used to determine the stratigraphic correlations from Northern Basin to Eastern Basin. It is proposed that high-resolution seismic data (~2000 kms) be acquired to address this issue.\u003cbr/\u003e\u003cbr/\u003eQuestion 2) Were extreme advances of the APIC across the shelf as frequent as inferred by Bart and Anderson (1995)? Bart and Anderson (1995) inferred that the APIC advanced across the continental shelf at least 30 times since the middle Miocene. This is significant because it suggests that the advances of the small APIC were an order of magnitude more frequent than the advances of the EAIS and WAIS. Others contest the Bart and Anderson (1995) glacial-unconformity interpretation of seismic reflections, and argue that the advances of the APIC were far fewer (i.e., Larter et al., 1997). The recent drilling on the Antarctic Peninsula outer continental shelf has sampled some but not all of the glacial units, but the sediment recovery was poor, and thus, the glacial history interpretation is still ambiguous. The existing high-resolution seismic grids from the Antarctic Peninsula contain only one regional strike line on the outer continental shelf. This is inadequate to address the controversy of the glacial-unconformity interpretation and the regional correlation of the recent ODP results. It is proposed that high-resolution seismic data (~1000 kms) be acquired in a forthcoming (January 2002) cruise to the Antarctic Peninsula to address these issues.\u003cbr/\u003e\u003cbr/\u003eThe second objective of this project is 1) to expand the PI\u0027s effort to integrate his ongoing and the proposed experiments into a graduate-level course at LSU, and 2) to develop a pilot outreach program with a Baton Rouge public high school. The Louisiana Department of Education has adopted scientific standards that apply to all sciences. These standards reflect what 9th through 12th grade-level students should be able to do and know. The PI will target one of these standards, the Science As Inquiry Standard 1 Benchmark. The PI will endeavor to share with the students the excitement of conducting scientific research as a way to encourage the students to pursue earth science as a field of study at the university level.", "east": 179.99944, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -72.00044, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Bart, Philip", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.73705, "title": "PECASE: Relative frequency and phase of extreme expansions of the Antarctic Ice Sheets during the late Neogene", "uid": "p0000593", "west": -179.99992}, {"awards": "9316767 Jeffries, Martin", "bounds_geometry": "POLYGON((-180 -43.56571,-144 -43.56571,-108 -43.56571,-72 -43.56571,-36 -43.56571,0 -43.56571,36 -43.56571,72 -43.56571,108 -43.56571,144 -43.56571,180 -43.56571,180 -46.304308,180 -49.042906,180 -51.781504,180 -54.520102,180 -57.2587,180 -59.997298,180 -62.735896,180 -65.474494,180 -68.213092,180 -70.95169,144 -70.95169,108 -70.95169,72 -70.95169,36 -70.95169,0 -70.95169,-36 -70.95169,-72 -70.95169,-108 -70.95169,-144 -70.95169,-180 -70.95169,-180 -68.213092,-180 -65.474494,-180 -62.735896,-180 -59.997298,-180 -57.2587,-180 -54.520102,-180 -51.781504,-180 -49.042906,-180 -46.304308,-180 -43.56571))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002231", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9505"}, {"dataset_uid": "002234", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9503"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The goal of this investigation is to understand the role of snow in sea ice development processes and air-ice-ocean heat exchange interactions in the seasonal and perennial sea ice zones of the Ross Sea, the Amundsen Sea, and the Bellingshausen Sea. Observations and measurements of the characteristics of sea ice and snow will be combined with numerical models of sea-ice flooding and the entrainment of snow into the ice cover in order to gain an understanding of the sea-ice heat and mass balance, and to quantify the energy exchange within the antarctic sea-ice cover. The snow measurement program, using the RVIB Nathaniel B. Palmer, will include depth, grain size and morphology, density, temperature, thermal conductivity, water content, and stable isotope ratio. The ice measurement program will include thickness, salinity, temperature, density, brine content, and included gas volume, as well as such structural properties as the fraction of frazil, platelet, and congelation ice in the seasonal antarctic pack ice. Differences in ice types are the result of differences in the environment in which the ice forms: frazil ice is formed in supercooled sea water, normally through wind or wave-induced turbulence, while platelet and congelation ice is formed under quiescent conditions. The fraction of frazil ice is an important variable in the energy budget of the upper ocean, and contributes significantly to the stabilization of the surface layers. The numerical models will involve the thermodynamics of phase changes from liquid water to ice, along with the resulting energy transfer, brine expulsion, and the modulating effect of a snow cover. The results are expected to have broad relevance and application to understanding the effects of sea-ice processes in global change, and atmospheric, oceanographic, and remote sensing investigations of the Southern Ocean.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56571, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jeffries, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -70.95169, "title": "The Role of Snow in Antarctic Sea Ice Development and Ocean-Atmosphere Energy Exchange", "uid": "p0000642", "west": -180.0}, {"awards": "0125562 Zachos, James", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0602A", "datasets": [{"dataset_uid": "001571", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0602A"}, {"dataset_uid": "002617", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0602A", "url": "https://www.rvdata.us/search/cruise/NBP0602A"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this \"demonstration cruise\" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the \"Greenhouse-Icehouse\" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program\u0027s technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the \"no man\u0027s land\" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program\u0027s vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ROCK CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, John", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Proposal: SHALDRIL - A Demonstration Drilling Cruise to the James Ross Basin", "uid": "p0000829", "west": null}, {"awards": "9814383 Domack, Eugene", "bounds_geometry": "POLYGON((-70.90625 -52.35392,-69.456459 -52.35392,-68.006668 -52.35392,-66.556877 -52.35392,-65.107086 -52.35392,-63.657295 -52.35392,-62.207504 -52.35392,-60.757713 -52.35392,-59.307922 -52.35392,-57.858131 -52.35392,-56.40834 -52.35392,-56.40834 -53.615031,-56.40834 -54.876142,-56.40834 -56.137253,-56.40834 -57.398364,-56.40834 -58.659475,-56.40834 -59.920586,-56.40834 -61.181697,-56.40834 -62.442808,-56.40834 -63.703919,-56.40834 -64.96503,-57.858131 -64.96503,-59.307922 -64.96503,-60.757713 -64.96503,-62.207504 -64.96503,-63.657295 -64.96503,-65.107086 -64.96503,-66.556877 -64.96503,-68.006668 -64.96503,-69.456459 -64.96503,-70.90625 -64.96503,-70.90625 -63.703919,-70.90625 -62.442808,-70.90625 -61.181697,-70.90625 -59.920586,-70.90625 -58.659475,-70.90625 -57.398364,-70.90625 -56.137253,-70.90625 -54.876142,-70.90625 -53.615031,-70.90625 -52.35392))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001985", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0003"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to study the region recently occupied by the Larsen Ice Shelf in the Antarctic Peninsula. Over the last 10 years, scientists have observed a dramatic decay and disintegration of floating ice shelves along the northern end of the Antarctic Peninsula. Meteorological records and satellite observations indicate that this catastrophic decay is related to regional warming of nearly 3 degrees C in the last 50 years. While such retreat of floating ice shelves is unprecedented in historic records, current understanding of the natural variability of ice shelf systems over the last few thousand years is not understood well. This award supports a program of marine geologic research directed at filling this knowledge gap by developing an understanding of the dynamics of the northern Larsen Ice Shelf during the Holocene epoch (the last 10,000 years).\u003cbr/\u003e\u003cbr/\u003eThe Larsen Ice Shelf is located in the NW Weddell Sea along the eastern side of the Antarctic Peninsula and is currently undergoing a rapid, catastrophic retreat as documented by satellite imagery over the past five years. While the region of the northern Antarctic Peninsula has experienced a pronounced warming trend over the last 40 years, the links between this warming and global change (i.e. greenhouse warming) are not obvious. Yet the ice shelf is clearly receding at a rate unprecedented in historic time, leaving vast areas of the seafloor uncovered and in an open marine setting. This project will collect a series of short sediment cores within the Larsen Inlet and in areas that were at one time covered by the Larsen Ice Shelf. By applying established sediment and fossil criteria to the cores we hope to demonstrate whether the Larsen Ice Shelf has experienced similar periods of retreat and subsequent advance within the last 10,000 years. Past work in various regions of the Antarctic has focused on depositional models for ice shelves that allow one to discern the timing of ice shelf retreat/advance in areas of the Ross Sea, Antarctic Peninsula, and Prydz Bay. This research will lead to a much improved understanding of the dynamics of ice shelf systems and their role in past and future climate oscillations.", "east": -56.40834, "geometry": "POINT(-63.657295 -58.659475)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.35392, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Domack, Eugene Walter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.96503, "title": "Paleohistory of the Larsen Ice Shelf: Evidence from the Marine Record", "uid": "p0000619", "west": -70.90625}, {"awards": "0338317 Stock, Joann; 0338346 Cande, Steven", "bounds_geometry": "POLYGON((-179.9987 71.33822,-143.998893 71.33822,-107.999086 71.33822,-71.999279 71.33822,-35.999472 71.33822,0.000334999999978 71.33822,36.000142 71.33822,71.999949 71.33822,107.999756 71.33822,143.999563 71.33822,179.99937 71.33822,179.99937 59.8431,179.99937 48.34798,179.99937 36.85286,179.99937 25.35774,179.99937 13.86262,179.99937 2.3675,179.99937 -9.12762,179.99937 -20.62274,179.99937 -32.11786,179.99937 -43.61298,143.999563 -43.61298,107.999756 -43.61298,71.999949 -43.61298,36.000142 -43.61298,0.000335000000007 -43.61298,-35.999472 -43.61298,-71.999279 -43.61298,-107.999086 -43.61298,-143.998893 -43.61298,-179.9987 -43.61298,-179.9987 -32.11786,-179.9987 -20.62274,-179.9987 -9.12762,-179.9987 2.3675,-179.9987 13.86262,-179.9987 25.35774,-179.9987 36.85286,-179.9987 48.34798,-179.9987 59.8431,-179.9987 71.33822))", "dataset_titles": "Expedition Data; Expedition data of NBP0501", "datasets": [{"dataset_uid": "001561", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0607A"}, {"dataset_uid": "001690", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304B"}, {"dataset_uid": "001587", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0507"}, {"dataset_uid": "001691", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304C"}, {"dataset_uid": "001577", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0602"}, {"dataset_uid": "001609", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0501B"}, {"dataset_uid": "001692", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304D"}, {"dataset_uid": "002627", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "001557", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0607C"}, {"dataset_uid": "001652", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0406"}, {"dataset_uid": "001512", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0804"}, {"dataset_uid": "001660", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0403"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project will utilize the R/VIB Nathaniel B. Palmer\u0027s transit cruises to collect marine geophysical data on targets-of-opportunity in the southern oceans. Because the Palmer generally traverses regions only sparsely surveyed with geophysical instruments, this project represents a cost-effective way to collect important new data. The work\u0027s focus is expanding our knowledge of plate motion histories for the Antarctic and surrounding plates. The ultimate goals are improving global plate reconstructions and gaining new insight into general plate kinematics and dynamics and lithospheric rheology. Only slight deviations from the straight routes are required, and we expect to operate on one cruise per year over the three years of the project. The first cruise from New Zealand to Chile will survey a flow line of Pacific-Antarctic plate motion along the Menard fracture zone, which crosses the East Pacific Rise at ~50 S latitude. Swath bathymetry, gravity, magnetics, and a small amount of seismic reflection profiling will be collected to determine the exact trace of the fracture zone and its relationship to the associated gravity anomaly seen in shipboard and satellite radar altimetry data. These observations are critical for precise plate reconstructions, and will provide GPS-navigated locations of a major fracture zone near the northern end of the Pacific-Antarctic boundary. These data will be used in combination with similar data from the Pitman fracture zone at the southwestern end of the plate boundary and magnetic anomalies from previous cruises near the Menard fracture zone to improve high-precision plate reconstructions and evaluate the limits of internal deformation of the Pacific and Antarctic plates. The science plan for cruises in following years will be designed once transit schedules are set. In terms of broader impacts, we plan to teach an on-board marine geophysics class to graduate and undergraduate students on two cruises. The class consists of daily classroom lectures about the instruments and data; several hours per day of watch standing and data processing; and work by each student on an independent research project. We expect to accommodate 15 students per class, including participants from primarily undergraduate institutions with high minority enrollments.", "east": 179.99937, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": 71.33822, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Croon, Marcel; Stock, Joann; Miller, Alisa; Cande, Steven; Gordon, Arnold", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -43.61298, "title": "Collaborative Research: Collection of Marine Geophysical Data on Transits of the Nathaniel B. Palmer", "uid": "p0000121", "west": -179.9987}, {"awards": "9317598 Asper, Vernon", "bounds_geometry": "POLYGON((-180 -43.56582,-144.00001 -43.56582,-108.00002 -43.56582,-72.00003 -43.56582,-36.00004 -43.56582,-0.000049999999987 -43.56582,35.99994 -43.56582,71.99993 -43.56582,107.99992 -43.56582,143.99991 -43.56582,179.9999 -43.56582,179.9999 -46.943299,179.9999 -50.320778,179.9999 -53.698257,179.9999 -57.075736,179.9999 -60.453215,179.9999 -63.830694,179.9999 -67.208173,179.9999 -70.585652,179.9999 -73.963131,179.9999 -77.34061,143.99991 -77.34061,107.99992 -77.34061,71.99993 -77.34061,35.99994 -77.34061,-0.000050000000016 -77.34061,-36.00004 -77.34061,-72.00003 -77.34061,-108.00002 -77.34061,-144.00001 -77.34061,-180 -77.34061,-180 -73.963131,-180 -70.585652,-180 -67.208173,-180 -63.830694,-180 -60.453215,-180 -57.075736,-180 -53.698257,-180 -50.320778,-180 -46.943299,-180 -43.56582))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002252", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9406"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9317598 Asper The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. This component will focus on the collection of vertical flux samples which will be analyzed for carbon, nitrogen and total mass flux and also provided to the other investigators for their specific analyses. Profiles of the abundance of large aggregates in the water column using a non- contact photographic method will be made. These data will be used to complement other particle determinations, to investigate the role of these aggregates in particle flux and to determine the mechanisms of particle export as a function of season and phytoplankton species. The end result will be a better understanding of the bloom processes and significant contributions to the data base on aggregates and export mechanisms in this environment.", "east": 179.9999, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56582, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Asper, Vernon; Smith, Walker", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.34061, "title": "Collaborative Research on Bloom Dynamics and Food Web Structure in the Ross Sea: Vertical Flux of Carbon and Nitrogen", "uid": "p0000646", "west": -180.0}, {"awards": "9419605 Dunbar, Robert; 9896356 Dunbar, Robert", "bounds_geometry": "POLYGON((-180 -43.56493,-144.00001 -43.56493,-108.00002 -43.56493,-72.00003 -43.56493,-36.00004 -43.56493,-0.000049999999987 -43.56493,35.99994 -43.56493,71.99993 -43.56493,107.99992 -43.56493,143.99991 -43.56493,179.9999 -43.56493,179.9999 -47.023783,179.9999 -50.482636,179.9999 -53.941489,179.9999 -57.400342,179.9999 -60.859195,179.9999 -64.318048,179.9999 -67.776901,179.9999 -71.235754,179.9999 -74.694607,179.9999 -78.15346,143.99991 -78.15346,107.99992 -78.15346,71.99993 -78.15346,35.99994 -78.15346,-0.000050000000016 -78.15346,-36.00004 -78.15346,-72.00003 -78.15346,-108.00002 -78.15346,-144.00001 -78.15346,-180 -78.15346,-180 -74.694607,-180 -71.235754,-180 -67.776901,-180 -64.318048,-180 -60.859195,-180 -57.400342,-180 -53.941489,-180 -50.482636,-180 -47.023783,-180 -43.56493))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002132", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9709"}, {"dataset_uid": "002154", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9606"}, {"dataset_uid": "002094", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9807"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Not Available", "east": 179.9999, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56493, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Dunbar, Robert", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.15346, "title": "Research on Ocean-Atmosphere Variability and Ecosystem Response in the Ross Sea (ROAVERRS)", "uid": "p0000635", "west": -180.0}, {"awards": "9816049 DeMaster, David", "bounds_geometry": "POLYGON((-70.90654 -52.35368,-70.220384 -52.35368,-69.534228 -52.35368,-68.848072 -52.35368,-68.161916 -52.35368,-67.47576 -52.35368,-66.789604 -52.35368,-66.103448 -52.35368,-65.417292 -52.35368,-64.731136 -52.35368,-64.04498 -52.35368,-64.04498 -53.639401,-64.04498 -54.925122,-64.04498 -56.210843,-64.04498 -57.496564,-64.04498 -58.782285,-64.04498 -60.068006,-64.04498 -61.353727,-64.04498 -62.639448,-64.04498 -63.925169,-64.04498 -65.21089,-64.731136 -65.21089,-65.417292 -65.21089,-66.103448 -65.21089,-66.789604 -65.21089,-67.47576 -65.21089,-68.161916 -65.21089,-68.848072 -65.21089,-69.534228 -65.21089,-70.220384 -65.21089,-70.90654 -65.21089,-70.90654 -63.925169,-70.90654 -62.639448,-70.90654 -61.353727,-70.90654 -60.068006,-70.90654 -58.782285,-70.90654 -57.496564,-70.90654 -56.210843,-70.90654 -54.925122,-70.90654 -53.639401,-70.90654 -52.35368))", "dataset_titles": "Expedition Data; Expedition data of LMG0003", "datasets": [{"dataset_uid": "002690", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0003", "url": "https://www.rvdata.us/search/cruise/LMG0003"}, {"dataset_uid": "001983", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0004"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "OPP98-15823 P.I. Craig Smith\u003cbr/\u003eOPP98-16049 P.I. David DeMaster\u003cbr/\u003e\u003cbr/\u003ePrimary production in Antarctic coastal waters is highly seasonal, yielding an intense pulse of biogenic particles to the continental shelf floor. This seasonal pulse may have major ramifications for carbon cycling, benthic ecology and material burial on the west Antarctic Peninsula (WAP) shelf. Thus, we propose a multii-disciplinary program to evaluate the seafloor accumulation, fate and benthic community impacts of bloom material along a transect of three stations crossing the Antarctic shelf in the Palmer LTER study area. Using a seasonal series of five cruises to our transect, we will test the following hypostheses: (1) A substantial proportion of spring/summer export production is deposited ont eh WAP shelf as phytodetritus or fecal pellets. (2) The deposited bloom production is a source of labile particulate organic carbon for benthos for an extended period of time (months). (3) Large amounts of labile bloom POC are rapidly subducted into the sediment column by the deposit-feeding and caching activities of benthos. (4) Macrobenthic detritivores sustain a rapid increase in biomass and abundance following the spring/summer particulate organic carbon pulse. To test these hypotheses, we will evaluate seabed deposition and lability of particulate organic carbon, patterns of particulate organic carbon mixing into sediments, seasonal variations in macrofaunal and megafaunal abundance, biomass and reproductive condition, and rates of particulate organic carbon and silica mineralization and accumulation in the seabed. Fluxes of biogenic materials and radionuclides into midwater particle traps will be contrasted with seabed deposition and burial rates to establish water-column and seabed preservation efficiencies for these materials. The project will substantially improve our understanding of the spring/summer production pulse on the WAP shelf and its impacts on seafloor communities and carbon cycling in Antarctic coastal systems.", "east": -64.04498, "geometry": "POINT(-67.47576 -58.782285)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP; R/V LMG", "locations": null, "north": -52.35368, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "DeMaster, David; Smith, Craig", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -65.21089, "title": "Collaborative Research: Bentho-Pelagic Coupling on the West Antarctic Peninsula Shelf: The Impact and Fate of Bloom Material at the Seafloor", "uid": "p0000618", "west": -70.90654}, {"awards": "9814692 Kellogg, Thomas", "bounds_geometry": "POLYGON((-179.99342 -58.74225,-143.994734 -58.74225,-107.996048 -58.74225,-71.997362 -58.74225,-35.998676 -58.74225,0.000010000000003 -58.74225,35.998696 -58.74225,71.997382 -58.74225,107.996068 -58.74225,143.994754 -58.74225,179.99344 -58.74225,179.99344 -60.716231,179.99344 -62.690212,179.99344 -64.664193,179.99344 -66.638174,179.99344 -68.612155,179.99344 -70.586136,179.99344 -72.560117,179.99344 -74.534098,179.99344 -76.508079,179.99344 -78.48206,143.994754 -78.48206,107.996068 -78.48206,71.997382 -78.48206,35.998696 -78.48206,0.000010000000003 -78.48206,-35.998676 -78.48206,-71.997362 -78.48206,-107.996048 -78.48206,-143.994734 -78.48206,-179.99342 -78.48206,-179.99342 -76.508079,-179.99342 -74.534098,-179.99342 -72.560117,-179.99342 -70.586136,-179.99342 -68.612155,-179.99342 -66.638174,-179.99342 -64.664193,-179.99342 -62.690212,-179.99342 -60.716231,-179.99342 -58.74225))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001992", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0001"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a marine geological investigation of the Amundsen Sea region toward a better understanding of the deglaciation history of the West Antarctic Ice Sheet (WAIS). The WAIS may be inherently unstable because it is the last marine-based ice sheet in the world. Unlike other embayments in West Antarctica, major ice streams draining into the Amundsen Sea from the interior of the WAIS lack buttressing ice shelves. Mass balance data for the distal portions of these ice streams (Pine Island and Thwaites glaciers) appear to be in balance or may be becoming negative. Because both ice streams have beds that slope downward toward the center of the ice sheet, grounding-line recession resulting from either continued thinning or sea-level rise could trigger irreversible grounding-line retreat, leading to ice-sheet disintegration and consequent global sea-level rise. The limited marine geological and geophysical data available from the Amundsen Sea suggest that grounded ice or an ice shelf occupied the inner Amundsen Sea embayment until perhaps as recently as 1000 to 2000 years ago, and this ice may have retreated rapidly in historic time.\u003cbr/\u003e\u003cbr/\u003eThis project, a study of the marine geology and geophysics of the Amundsen Sea continental shelf from 100 degrees W to 130 degrees W, is designed to address the Amundsen Sea part of WAIS Science Plan Priority Goal H2: \"What is the deglaciation history in the eastern Ross, the Bellingshausen and Amundsen Seas?\" This project will examine bathymetric data of the Amundsen Sea continental shelf to determine the positions of former ice-steam channels, and to aid in choosing sites for sediment coring. Single-channel seismic reflection studies will be conducted in order to determine sediment-thickness patterns, to aid in choice of coring sites, and to locate and identify morphologic features indicative of former grounded ice (e.g., moraines, scours, flutes, striations, till wedges and deltas, etc.). Coring will be concentrated along former ice flow-lines. Core samples will be analyzed in the laboratory for sedimentology, to determine whether of not basal tills are present (indicating former grounded ice and its former extent), and for calcareous and siliceous microfossils. The chronology of grounding-line and ice-shelf retreat from a presumed Last Glacial Maximum position near the shelf break will be established using accelerator mass spectrometry (AMS) carbon-14 dates of acid-insoluble particulate organic carbon.\u003cbr/\u003e\u003cbr/\u003eThis project will share ship time in the Amundsen Sea with a physical oceanographic project. Marine geologic data and samples collected will be integrated with findings of other investigators toward developing a comprehensive interpretation of the history of the WAIS.", "east": 179.99344, "geometry": "POINT(0.000010000000003 -68.612155)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -58.74225, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kellogg, Thomas; Jacobs, Stanley", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.48206, "title": "Glacial History of the Amundsen Sea Shelf", "uid": "p0000620", "west": -179.99342}, {"awards": "0636639 MacPhee, Ross", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG0717; Expedition data of LMG0902", "datasets": [{"dataset_uid": "002669", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0902", "url": "https://www.rvdata.us/search/cruise/LMG0902"}, {"dataset_uid": "001520", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0717"}, {"dataset_uid": "002727", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0902", "url": "https://www.rvdata.us/search/cruise/LMG0902"}, {"dataset_uid": "002677", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0717", "url": "https://www.rvdata.us/search/cruise/LMG0717"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This exploratory project searches for fossils on Livingston Island in the South Shetland Islands off of the Antarctic peninsula. Strata there date from 125 to 99 million years in age, a critical time in the development of various flora and fauna. With so many unknowns in the biotic history of the Antarctic, any finds of vertebrate fossils on this little explored island will be of great significance. One key question is marsupial evolution. It is assumed that marsupials of South America and Australia transited through Antarctica, but a supporting fossil record has yet to be discovered. Related investigations on Mesozoic climate will be performed through stable isotope analysis of clay and rock samples. The broader impacts of the project include graduate student education and public outreach through a museum exhibit.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "MacPhee, Ross; DeMaster, David", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Vertebrate Paleontology of Livingston Island, South Shetlands, Antarctica", "uid": "p0000858", "west": null}, {"awards": "9815961 Bengtson, John", "bounds_geometry": "POLYGON((-179.99905 -43.56728,-143.99915 -43.56728,-107.99925 -43.56728,-71.99935 -43.56728,-35.99945 -43.56728,0.000450000000001 -43.56728,36.00035 -43.56728,72.00025 -43.56728,108.00015 -43.56728,144.00005 -43.56728,179.99995 -43.56728,179.99995 -47.058498,179.99995 -50.549716,179.99995 -54.040934,179.99995 -57.532152,179.99995 -61.02337,179.99995 -64.514588,179.99995 -68.005806,179.99995 -71.497024,179.99995 -74.988242,179.99995 -78.47946,144.00005 -78.47946,108.00015 -78.47946,72.00025 -78.47946,36.00035 -78.47946,0.000450000000001 -78.47946,-35.99945 -78.47946,-71.99935 -78.47946,-107.99925 -78.47946,-143.99915 -78.47946,-179.99905 -78.47946,-179.99905 -74.988242,-179.99905 -71.497024,-179.99905 -68.005806,-179.99905 -64.514588,-179.99905 -61.02337,-179.99905 -57.532152,-179.99905 -54.040934,-179.99905 -50.549716,-179.99905 -47.058498,-179.99905 -43.56728))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001997", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9909"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9815961 \u003cbr/\u003eBENGTSON\u003cbr/\u003eThe pack ice region surrounding Antarctica contains at least fifty percent of the world\u0027s population of seals, comprising about eighty percent of the world\u0027s total pinniped biomass. As a group, these seals are among the dominant top predators in Southern Ocean ecosystems, and the fluctuation in their abundance, growth patterns, life histories, and behavior provide a potential source of information about environmental variability integrated over a wide range of spatial and temporal scales. This proposal was developed as part of the international Antarctic Pack Ice Seals (APIS) program, which is aimed to better understand the ecological relationships between the distribution of pack ice seals and their environment. During January-February, 2000, a research cruise through the pack ice zone of the eastern Ross Sea and western Amundsen Sea will be conducted to survey and sample along six transects perpendicular to the continental shelf. Each of these transects will pass through five environmental sampling strata: continental shelf zone, Antarctic slope front, pelagic zone, the ice edge front, and the open water outside the pack ice zone. All zones but open water will be ice-covered to some degree. Surveys along each transect will gather data on bathymetry, hydrography, sea ice dynamics and characteristics, phytoplankton and ice algae stocks, prey species (e.g., fish, cephalopods and euphausiids), and seal distribution, abundance and diet. This physical and trophic approach to investigating ecological interactions among pack ice seals, prey and the physical environment will allow the interdisciplinary research team to test the hypothesis that there are measurable physical and biological features in the Southern Ocean that result in area of high biological activity by upper trophic level predators. Better insight into the interplay among pack ice seals and biological and physical features of Antarctic marine ecosystems will allow for a better prediction of fluctuation in seal population in the context of environmental change.", "east": 179.99995, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56728, "nsf_funding_programs": null, "paleo_time": null, "persons": "Bengtson, John", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.47946, "title": "Antarctic Pack Ice Seals: Ecological Interactions with Prey and the Environment", "uid": "p0000614", "west": -179.99905}, {"awards": "0636696 DeVries, Arthur", "bounds_geometry": "POLYGON((-68.0025 -52.7599,-67.07254 -52.7599,-66.14258 -52.7599,-65.21262 -52.7599,-64.28266 -52.7599,-63.3527 -52.7599,-62.42274 -52.7599,-61.49278 -52.7599,-60.56282 -52.7599,-59.63286 -52.7599,-58.7029 -52.7599,-58.7029 -53.98242,-58.7029 -55.20494,-58.7029 -56.42746,-58.7029 -57.64998,-58.7029 -58.8725,-58.7029 -60.09502,-58.7029 -61.31754,-58.7029 -62.54006,-58.7029 -63.76258,-58.7029 -64.9851,-59.63286 -64.9851,-60.56282 -64.9851,-61.49278 -64.9851,-62.42274 -64.9851,-63.3527 -64.9851,-64.28266 -64.9851,-65.21262 -64.9851,-66.14258 -64.9851,-67.07254 -64.9851,-68.0025 -64.9851,-68.0025 -63.76258,-68.0025 -62.54006,-68.0025 -61.31754,-68.0025 -60.09502,-68.0025 -58.8725,-68.0025 -57.64998,-68.0025 -56.42746,-68.0025 -55.20494,-68.0025 -53.98242,-68.0025 -52.7599))", "dataset_titles": "Expedition Data; Expedition data of LMG0809; Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae)", "datasets": [{"dataset_uid": "601811", "doi": null, "keywords": "Antarctica; Bellingshausen Sea; Cryosphere; Southern Ocean", "people": "Desvignes, Thomas; McDowell, Jan; Cheng, Chi-Hing; Biesack, Ellen; Steinberg, Deborah; Hilton, Eric; Corso, Andrew", "repository": "USAP-DC", "science_program": "LTER", "title": "Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae)", "url": "https://www.usap-dc.org/view/dataset/601811"}, {"dataset_uid": "001504", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0809"}, {"dataset_uid": "002728", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0809", "url": "https://www.rvdata.us/search/cruise/LMG0809"}, {"dataset_uid": "001493", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0810"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Antarctic notothenioid fish evolved antifreeze (AF) proteins that prevent ice crystals that enter their body fluids from growing, and thereby avoid freezing in their icy habitats. However, even in the extreme cold Antarctic marine environment, regional gradations of severity are found. The biological correlate for environmental severity in fish is the endogenous ice load, which likely determines the tolerable limit of environmental severity for notothenioid habitation. The endogenous ice load develops from environmental ice crystals entering through body surfaces and somehow localizing to the spleen. How prone the surface tissues are to ice entry, how ice reaches the spleen, and what the fate of splenic ice is, requires elucidation. Spleen sequestration of ice raises the hypothesis that macrophages may play a role in the translocation and perhaps elimination of AF-bound ice crystals. Antifreeze glycoproteins (AFGP) act in concert with a second, recently discovered antifreeze called antifreeze potentiating protein (AFPP), necessitating an assessment of the contribution of AFPP to freezing avoidance. Recent research suggests that the exocrine pancreas and the anterior stomach, not the liver, synthesize AFGPs and secrete them into the intestine, from where they may be returned to the blood. A GI-to-blood transport is a highly unconventional path for a major plasma protein and also begs the questions, What is the source of blood AFPP?. Why are two distinct AF proteins needed and what is the chronology of their evolution? What genomic changes in the DNA are associated with the development or loss of the antifreeze trait? Experiments described in this proposal address these interrelated questions of environmental, organismal, and evolutionary physiology, and will further our understanding of novel vertebrate physiologies, the limits of environmental adaptation, and climatically driven changes in the genome. The proposed research will (1) determine the temporal and spatial heterogeneity of environmental temperature and iciness in progressively more severe fish habitats in the greater McMurdo Sound area, and in the milder Arthur Harbor at Palmer Station. The splenic ice load in fishes inhabiting these sites will be determined to correlate to environmental severity and habitability. (2) Assess the surface tissue site of ice entry and their relative barrier properties in intact fish and isolated tissues preparations (3) Assess the role of immune cells in the fate of endogenous ice, (4) determine whether the blood AFGPs are from intestinal/rectal uptake, (5) examine the contribution of AFPP to the total blood AF activity (6) evaluate the progression of genomic changes in the AFGP locus across Notothenioidei as modulated by disparate thermal environments, in four selected species through the analyses of large insert DNA BAC clones. The origin and evolution of AFPP will be examined also by analyzing BAC clones encompassing the AFPP genomic locus. The broader impacts of the proposed research include training of graduate and undergraduate students in research approaches ranging from physical field measurements to cutting edge genomics. Undergraduate research projects have lead to co-authored publications and will continue to do so. Outreach includes establishing Wiki websites on topics of Antarctic fish biology and freeze avoidance, providing advisory services to the San Francisco Science Exploratorium, and making BAC libraries available to interested polar biologists. This research theme has repeatedly received national and international science news coverage and will continue to be disseminated to the public in that manner.", "east": -58.7029, "geometry": "POINT(-63.3527 -58.8725)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.7599, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Devries, Arthur", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -64.9851, "title": "Environmental, Organismal and Evolutionary Physiology of Freeze Avoidance in Antarctic Notothenioid Fishes", "uid": "p0000560", "west": -68.0025}, {"awards": "0003619 Dalziel, Ian", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG9810", "datasets": [{"dataset_uid": "002092", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG9810"}, {"dataset_uid": "002678", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG9810", "url": "https://www.rvdata.us/search/cruise/LMG9810"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a collaborative research program to initiate a Global Positioning System (GPS) network to measure crustal motions in the bedrock surrounding and underlying the West Antarctic Ice Sheet (WAIS). Evaluation of the role of both tectonic and ice-induced crustal motions of the WAIS bedrock is a critical goal for understanding past, present, and future dynamics of WAIS and its potential role in future global change scenarios, as well as improving our understanding of the role of Antarctica in global plate motions. The extent of active tectonism in West Antarctica is largely speculative, as few data exist that constrain its geographic distribution, directions, or rates of deformation. Active tectonism and the influence of bedrock on the WAIS have been highlighted recently by geophysical data indicating active subglacial volcanism and control of ice streaming by the presence of sedimentary basins. The influence of bedrock crustal motion on the WAIS and its future dynamics is a fundamental issue. Existing GPS projects are located only on the fringe of the ice sheet and do not address the regional picture. It is important that baseline GPS measurements on the bedrock around and within the WAIS be started so that a basis is established for detecting change.\u003cbr/\u003e\u003cbr/\u003eTo measure crustal motions, this project will build a West Antarctica GPS Network (WAGN) of at least 15 GPS sites across the interior of West Antarctica (approximately the size of the contiguous United States from the Rocky Mountains to the Pacific coast) over a two-year period beginning in the Antarctic field season 2001-2002. The planned network is designed using the Multi-modal Occupation Strategy (MOST), in which a small number of independent GPS \"roving\" receivers make differential measurements against a network of continuous GPS stations for comparatively short periods at each site. This experimental strategy, successfully implemented by a number of projects in California, S America, the SW Pacific and Central Asia, minimizes logistical requirements, an essential element of application of GPS geodesy in the scattered and remote outcrops of the WAIS bedrock.\u003cbr/\u003e\u003cbr/\u003eThe WAGN program will be integrated with the GPS network that has been established linking the Antarctic Peninsula with South America through the Scotia arc (Scotia Arc GPS Project (SCARP)). It will also interface with stations currently measuring motion across the Ross Embayment, and with the continent-wide GIANT program of the Working Group on Geodesy and Geographic Information Systems of the Scientific Committee on Antarctic Research (SCAR). The GPS network will be based on permanent monuments set in solid rock outcrops that will have near-zero set-up error for roving GPS occupations, and that can be directly converted to a continuous GPS site when future technology makes autonomous operation and satellite data linkage throughout West Antarctica both reliable and economical. The planned network both depends on and complements the existing and planned continuous networks. It is presently not practical, for reasons of cost and logistics, to accomplish the measurements proposed herein with either a network of continuous stations or traditional campaigns.\u003cbr/\u003e\u003cbr/\u003eThe proposed WAGN will complement existing GPS projects by filling a major gap in coverage among several discrete crustal blocks that make up West Antarctica, a critical area of potential bedrock movements. If crustal motions are relatively slow, meaningful results will only begin to emerge within the five-year maximum period of time for an individual funded project. Hence this proposal is only to initiate the network and test precision and velocities at the most critical sites. Once built, however, the network will yield increasingly meaningful results with the passage of time. Indeed, the slower the rates turn out to be, the more important an early start to measuring. It is anticipated that the results of this project will initiate an iterative process that will gradually resolve into an understanding of the contributions from plate rotations and viscoelastic and elastic motions resulting from deglaciation and ice mass changes. Velocities obtained from initial reoccupation of the most critical sites will dictate the timing of a follow-up proposal for reoccupation of the entire network when detectable motions have occurred.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Dalziel, Ian W.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: A GPS Network to Determine Crustal Motions in the Bedrock of the West Antarctic Ice Sheet: Phase I - Installation", "uid": "p0000859", "west": null}, {"awards": "9220848 Bartek, Louis", "bounds_geometry": "POLYGON((-179.9996 -52.35472,-143.99968 -52.35472,-107.99976 -52.35472,-71.99984 -52.35472,-35.99992 -52.35472,0 -52.35472,35.99992 -52.35472,71.99984 -52.35472,107.99976 -52.35472,143.99968 -52.35472,179.9996 -52.35472,179.9996 -54.916322,179.9996 -57.477924,179.9996 -60.039526,179.9996 -62.601128,179.9996 -65.16273,179.9996 -67.724332,179.9996 -70.285934,179.9996 -72.847536,179.9996 -75.409138,179.9996 -77.97074,143.99968 -77.97074,107.99976 -77.97074,71.99984 -77.97074,35.99992 -77.97074,0 -77.97074,-35.99992 -77.97074,-71.99984 -77.97074,-107.99976 -77.97074,-143.99968 -77.97074,-179.9996 -77.97074,-179.9996 -75.409138,-179.9996 -72.847536,-179.9996 -70.285934,-179.9996 -67.724332,-179.9996 -65.16273,-179.9996 -62.601128,-179.9996 -60.039526,-179.9996 -57.477924,-179.9996 -54.916322,-179.9996 -52.35472))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002245", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9407"}, {"dataset_uid": "002265", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9307"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award supports an integrated seismic, sedimentologic, and paleontologic investigation of glacio-marine stratigraphy of the Ross Sea continental shelf. The purpose of this work is to acquire seismic images and sediment cores of the glacial sediments toward a better understanding of the Cenozoic history of glaciation in the Ross Sea region. This investigation will utilize high resolution seismic profiling data to locate regions where the Pleistocene glacial till is thin or perhaps absent. Piston coring at these locations, if the till is penetrated, will provide sedimentary records of Cenozoic depositional environments and could provide important clues to fluctuations of the Antarctic Ice Sheets. The seismic profiling will provide a direct record of the grounding history of the Ross Ice Shelf during the Pleistocene and it will also allow first order correlations of Cenozoic sedimentary units that are represented by sediments recovered in the piston cores. This work will provide important proxy records of the history of both the West Antarctic Ice Sheet and the East Antarctic Ice Sheet and this, in turn, will provide important constraints to climate models.", "east": 179.9996, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.35472, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Bartek, Louis", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.97074, "title": "Integrated Biostratigraphy and High Resolution Seismic Stratigraphy of the Ross Sea: Implications for Cenozoic Eustatic and Climatic Change", "uid": "p0000643", "west": -179.9996}, {"awards": "9910175 Vernet, Maria; 9909933 Ross, Robin", "bounds_geometry": "POLYGON((-71.077 -57.9543,-70.015 -57.9543,-68.953 -57.9543,-67.891 -57.9543,-66.829 -57.9543,-65.767 -57.9543,-64.705 -57.9543,-63.643 -57.9543,-62.581 -57.9543,-61.519 -57.9543,-60.457 -57.9543,-60.457 -58.98629,-60.457 -60.01828,-60.457 -61.05027,-60.457 -62.08226,-60.457 -63.11425,-60.457 -64.14624,-60.457 -65.17823,-60.457 -66.21022,-60.457 -67.24221,-60.457 -68.2742,-61.519 -68.2742,-62.581 -68.2742,-63.643 -68.2742,-64.705 -68.2742,-65.767 -68.2742,-66.829 -68.2742,-67.891 -68.2742,-68.953 -68.2742,-70.015 -68.2742,-71.077 -68.2742,-71.077 -67.24221,-71.077 -66.21022,-71.077 -65.17823,-71.077 -64.14624,-71.077 -63.11425,-71.077 -62.08226,-71.077 -61.05027,-71.077 -60.01828,-71.077 -58.98629,-71.077 -57.9543))", "dataset_titles": "Expedition Data; Expedition data of LMG0205; Expedition data of NBP0104; Expedition data of NBP0202; Expedition data of NBP0204", "datasets": [{"dataset_uid": "002657", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0104", "url": "https://www.rvdata.us/search/cruise/NBP0104"}, {"dataset_uid": "002586", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0202", "url": "https://www.rvdata.us/search/cruise/NBP0202"}, {"dataset_uid": "002704", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0205", "url": "https://www.rvdata.us/search/cruise/LMG0205"}, {"dataset_uid": "001861", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0106"}, {"dataset_uid": "001856", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0105"}, {"dataset_uid": "001757", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0205"}, {"dataset_uid": "002643", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0204", "url": "https://www.rvdata.us/search/cruise/NBP0204"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The U.S. Global Ocean Ecosystems Dynamics (U.S. GLOBEC) program has the goal of understanding and ultimately predicting how populations of marine animal species respond to natural and anthropogenic changes in climate. Research in the Southern Ocean (SO) indicates strong coupling between climatic processes and ecosystem dynamics via the annual formation and destruction of sea ice. The Southern Ocean GLOBEC Program (SO GLOBEC) will investigate the dynamic relationship between physical processes and ecosystem responses through identification of critical parameters that affect the distribution, abundance and population dynamics of target species. The overall goals of the SO GLOBEC program are to elucidate shelf circulation processes and their effect on sea ice formation and krill distribution, and to examine the factors which govern krill survivorship and availability to higher trophic levels, including penguins, seals and whales. The focus of the U.S. contribution to the international SO GLOBEC program will be on winter processes. This component will focus on water-column primary production using direct experimental estimates, modeling restuls from a fast repetition rate fluorometer and modeling of primary production from both optical as well as biophysical models. This research will be coordinated with components focused on sea ice production and sea ice habitat. The result of the integrated SO GLOBEC program will be to improve the predictability of living marine resources, especially with respect to local and global climatic shifts.", "east": -60.457, "geometry": "POINT(-65.767 -63.11425)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V LMG; R/V NBP", "locations": null, "north": -57.9543, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Vernet, Maria; Costa, Daniel; Ross, Robin Macurda; Smith, Raymond", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -68.2742, "title": "GLOBEC: Winter Ecology of Larval Krill: Quantifying their Interaction with the Pack Ice Habitat", "uid": "p0000605", "west": -71.077}, {"awards": "0125818 Gargett, Ann", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0508", "datasets": [{"dataset_uid": "002610", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0508", "url": "https://www.rvdata.us/search/cruise/NBP0508"}, {"dataset_uid": "001584", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0508"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V NBP; B-15J", "locations": "B-15J", "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Neale, Patrick", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Interactive effects of UV and vertical mixing on phytoplankton and bacterioplankton in the Ross Sea", "uid": "p0000822", "west": null}, {"awards": "9815823 Smith, Craig", "bounds_geometry": "POLYGON((-70.90683 -52.35533,-69.8661302 -52.35533,-68.8254304 -52.35533,-67.7847306 -52.35533,-66.7440308 -52.35533,-65.703331 -52.35533,-64.6626312 -52.35533,-63.6219314 -52.35533,-62.5812316 -52.35533,-61.5405318 -52.35533,-60.499832 -52.35533,-60.499832 -53.818664,-60.499832 -55.281998,-60.499832 -56.745332,-60.499832 -58.208666,-60.499832 -59.672,-60.499832 -61.135334,-60.499832 -62.598668,-60.499832 -64.062002,-60.499832 -65.525336,-60.499832 -66.98867,-61.5405318 -66.98867,-62.5812316 -66.98867,-63.6219314 -66.98867,-64.6626312 -66.98867,-65.703331 -66.98867,-66.7440308 -66.98867,-67.7847306 -66.98867,-68.8254304 -66.98867,-69.8661302 -66.98867,-70.90683 -66.98867,-70.90683 -65.525336,-70.90683 -64.062002,-70.90683 -62.598668,-70.90683 -61.135334,-70.90683 -59.672,-70.90683 -58.208666,-70.90683 -56.745332,-70.90683 -55.281998,-70.90683 -53.818664,-70.90683 -52.35533))", "dataset_titles": "Expedition Data; Expedition data of LMG0009", "datasets": [{"dataset_uid": "001983", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0004"}, {"dataset_uid": "002689", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0009", "url": "https://www.rvdata.us/search/cruise/LMG0009"}, {"dataset_uid": "001811", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0009"}, {"dataset_uid": "001880", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0102"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "OPP98-15823 P.I. Craig Smith\u003cbr/\u003eOPP98-16049 P.I. David DeMaster\u003cbr/\u003e\u003cbr/\u003ePrimary production in Antarctic coastal waters is highly seasonal, yielding an intense pulse of biogenic particles to the continental shelf floor. This seasonal pulse may have major ramifications for carbon cycling, benthic ecology and material burial on the west Antarctic Peninsula (WAP) shelf. Thus, we propose a multii-disciplinary program to evaluate the seafloor accumulation, fate and benthic community impacts of bloom material along a transect of three stations crossing the Antarctic shelf in the Palmer LTER study area. Using a seasonal series of five cruises to our transect, we will test the following hypostheses: (1) A substantial proportion of spring/summer export production is deposited ont eh WAP shelf as phytodetritus or fecal pellets. (2) The deposited bloom production is a source of labile particulate organic carbon for benthos for an extended period of time (months). (3) Large amounts of labile bloom POC are rapidly subducted into the sediment column by the deposit-feeding and caching activities of benthos. (4) Macrobenthic detritivores sustain a rapid increase in biomass and abundance following the spring/summer particulate organic carbon pulse. To test these hypotheses, we will evaluate seabed deposition and lability of particulate organic carbon, patterns of particulate organic carbon mixing into sediments, seasonal variations in macrofaunal and megafaunal abundance, biomass and reproductive condition, and rates of particulate organic carbon and silica mineralization and accumulation in the seabed. Fluxes of biogenic materials and radionuclides into midwater particle traps will be contrasted with seabed deposition and burial rates to establish water-column and seabed preservation efficiencies for these materials. The project will substantially improve our understanding of the spring/summer production pulse on the WAP shelf and its impacts on seafloor communities and carbon cycling in Antarctic coastal systems.", "east": -60.499832, "geometry": "POINT(-65.703331 -59.672)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP; R/V LMG", "locations": null, "north": -52.35533, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Craig", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": "LTER", "south": -66.98867, "title": "Bentho-Pelagic Coupling on the West Antarctic Peninsula Shelf: The Impact and Fate of Bloom Material at the Seafloor", "uid": "p0000610", "west": -70.90683}, {"awards": "9614844 Jeffries, Martin", "bounds_geometry": "POLYGON((-180 -43.56557,-144 -43.56557,-108 -43.56557,-72 -43.56557,-36 -43.56557,0 -43.56557,36 -43.56557,72 -43.56557,108 -43.56557,144 -43.56557,180 -43.56557,180 -46.996716,180 -50.427862,180 -53.859008,180 -57.290154,180 -60.7213,180 -64.152446,180 -67.583592,180 -71.014738,180 -74.445884,180 -77.87703,144 -77.87703,108 -77.87703,72 -77.87703,36 -77.87703,0 -77.87703,-36 -77.87703,-72 -77.87703,-108 -77.87703,-144 -77.87703,-180 -77.87703,-180 -74.445884,-180 -71.014738,-180 -67.583592,-180 -64.152446,-180 -60.7213,-180 -57.290154,-180 -53.859008,-180 -50.427862,-180 -46.996716,-180 -43.56557))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002003", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9901"}, {"dataset_uid": "002110", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9803"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is a study of the effects of antarctic sea ice in the global climate system, through an examination of how the spatial distribution of ice and snow thickness and of open water is reflected in satellite-based synthetic aperture radar (SAR) imagery. The field investigations will be carried out from the RVIB Nathaniel B. Palmer in winter 1998 and summer 1999, and will produce observations of the snow and ice distribution, the crystal structure, stable isotopes, salinity and temperature structure of ice cores, and the stratigraphy, grain size, and water content of the snow cover. The SAR images from ERS-2 and RADARSAT will be acquired at the McMurdo ground station, and processed at the Alaska SAR Facility. These will provide information about the large-scale ice motion field and the small-scale ice deformation field, both of which contribute to the observed ice thickness distribution. In addition, a study of the spatial and temporal variation of the backscattered microwave energy will contribute to the development of numerical models that simulate the dynamic and thermodynamic interactions among the sea ice, ocean, and atmosphere. The surface data is vital for the extraction of environmental information from the radar data, and for the ultimate validation of interactive models.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56557, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jeffries, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.87703, "title": "Dynamic/Thermodynamic Processes and Their Contribution to the Sea Ice Thickness Distribution and Radar Backscatter in the Ross Sea", "uid": "p0000628", "west": -180.0}, {"awards": "9910164 Scheltema, Rudolf", "bounds_geometry": "POLYGON((-70.557 -52.351,-68.9316 -52.351,-67.3062 -52.351,-65.6808 -52.351,-64.0554 -52.351,-62.43 -52.351,-60.8046 -52.351,-59.1792 -52.351,-57.5538 -52.351,-55.9284 -52.351,-54.303 -52.351,-54.303 -53.60557,-54.303 -54.86014,-54.303 -56.11471,-54.303 -57.36928,-54.303 -58.62385,-54.303 -59.87842,-54.303 -61.13299,-54.303 -62.38756,-54.303 -63.64213,-54.303 -64.8967,-55.9284 -64.8967,-57.5538 -64.8967,-59.1792 -64.8967,-60.8046 -64.8967,-62.43 -64.8967,-64.0554 -64.8967,-65.6808 -64.8967,-67.3062 -64.8967,-68.9316 -64.8967,-70.557 -64.8967,-70.557 -63.64213,-70.557 -62.38756,-70.557 -61.13299,-70.557 -59.87842,-70.557 -58.62385,-70.557 -57.36928,-70.557 -56.11471,-70.557 -54.86014,-70.557 -53.60557,-70.557 -52.351))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001846", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0109"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Because of the extreme isolation of Antarctica since the early Oligocene one can expect to encounter a unique invertebrate fauna with a high degree of endemism. Yet, some benthic taxa include from 20 to \u003e50 percent non-endemic species. To account for such species it has been proposed that an intermittent reciprocal exchange must occur between the antiboreal populations of South America and the Antarctic continent. One possible means by which the geographical distribution can be maintained and genetic exchange may be accomplished is by the passive dispersal of planktonic larvae. To show that such dispersal is actually accomplished it must be demonstrated that (1) larvae of sublittoral species actually are found within the Drake passage and that such larvae belong to species that occur both in the antiboreal South American and Antarctic faunas and (2) that a hydrographic mechanism exists that can explain how the passive transport of larvae may occur between the two continents. The proposed research will address these two requirements by making transects of plankton samples across the Drake passage and by examining the possibility of cross frontal exchange of larvae at the subantarctic and polar fronts of the Antarctic circumpolar current as well as the possible transport of larvae in mesoscale rings. The outcome may suggest species that in the future may profitably be examined using molecular techniques, comparing individuals from bottom populations of South America and Antarctica. The study necessarily must be of a very preliminary nature since the occurrence of planktonic larvae of sublittoral benthic species in the Drake Passage has never before been examined.", "east": -54.303, "geometry": "POINT(-62.43 -58.62385)", "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.351, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Scheltema, Rudolf; Veit, Richard", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.8967, "title": "SGER: Dispersal of Planktonic Invertebrate Larvae and the Biogeography of the Antarctic Benthos", "uid": "p0000602", "west": -70.557}, {"awards": "0088143 Luyendyk, Bruce; 0087392 Bartek, Louis", "bounds_geometry": "POLYGON((-179.99786 -75.91667,-143.99852 -75.91667,-107.99918 -75.91667,-71.99984 -75.91667,-36.0005 -75.91667,-0.00115999999997 -75.91667,35.99818 -75.91667,71.99752 -75.91667,107.99686 -75.91667,143.9962 -75.91667,179.99554 -75.91667,179.99554 -76.183531,179.99554 -76.450392,179.99554 -76.717253,179.99554 -76.984114,179.99554 -77.250975,179.99554 -77.517836,179.99554 -77.784697,179.99554 -78.051558,179.99554 -78.318419,179.99554 -78.58528,143.9962 -78.58528,107.99686 -78.58528,71.99752 -78.58528,35.99818 -78.58528,-0.00116000000003 -78.58528,-36.0005 -78.58528,-71.99984 -78.58528,-107.99918 -78.58528,-143.99852 -78.58528,-179.99786 -78.58528,-179.99786 -78.318419,-179.99786 -78.051558,-179.99786 -77.784697,-179.99786 -77.517836,-179.99786 -77.250975,-179.99786 -76.984114,-179.99786 -76.717253,-179.99786 -76.450392,-179.99786 -76.183531,-179.99786 -75.91667))", "dataset_titles": "Expedition Data; NBP0301 data; NBP0306 data", "datasets": [{"dataset_uid": "000105", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0306 data", "url": "https://www.rvdata.us/search/cruise/NBP0306"}, {"dataset_uid": "001724", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0301"}, {"dataset_uid": "001668", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0306"}, {"dataset_uid": "000104", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0301 data", "url": "https://www.rvdata.us/search/cruise/NBP0301"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Luyendyk et.al.: OPP 0088143\u003cbr/\u003eBartek: OPP 0087392\u003cbr/\u003eDiebold: OPP 0087983\u003cbr/\u003e\u003cbr/\u003eThis award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a collaborative research program in marine geology and geophysics in the southern central and eastern Ross Sea. The project will conduct sites surveys for drilling from the Ross Ice Shelf into the seafloor beneath it. Many of the outstanding problems concerning the evolution of the East and West Antarctic Ice Sheets, Antarctic climate, global sea level, and the tectonic history of the West Antarctic Rift System can be addressed by drilling into the seafloor of the Ross Sea. Climate data for Cretaceous and Early Cenozoic time are lacking for this sector of Antarctica. Climate questions include: Was there any ice in Late Cretaceous time? What was the Antarctic climate during the Paleocene-Eocene global warming? When was the Cenozoic onset of Antarctic glaciation, when did glaciers reach the coast and when did they advance out onto the margin? Was the Ross Sea shelf non-marine in Late Cretaceous time; when did it become marine? Tectonic questions include: What was the timing of the Cretaceous extension in the Ross Sea rift; where was it located? What is the basement composition and structure? Where are the time and space limits of the effects of Adare Trough spreading? Another drilling objective is to sample and date the sedimentary section bounding the mapped RSU6 unconformity in the Eastern Basin and Central Trough to resolve questions about its age and regional extent. Deep Sea Drilling Project (DSDP) Leg 28 completed sampling at four drill sites in the early 1970\u0027s but had low recovery and did not sample the Early Cenozoic. Other drilling has been restricted to the McMurdo Sound area of the western Ross Sea and results can be correlated into the Victoria Land Basin but not eastward across basement highs. Further, Early Cenozoic and Cretaceous rocks have not been sampled. A new opportunity is developing to drill from the Ross Ice Shelf. This is a successor program to the Cape Roberts Drilling Project. One overriding difficulty is the need for site surveys at drilling locations under the ice shelf. This project will overcome this impediment by conducting marine geophysical drill site surveys at the front of the Ross Ice Shelf in the Central Trough and Eastern Basin. The surveys will be conducted a kilometer or two north of the ice shelf front where recent calving events have resulted in a southerly position of the ice shelf edge. In several years the northward advance of the ice shelf will override the surveyed locations and drilling could be accomplished. Systems to be used include swath bathymetry, gravity, magnetics, chirp sonar, high resolution seismic profiling, and 48 fold seismics. Cores will be collected to obtain samples for geotechnical properties, to study sub-ice shelf modern sedimentary processes, and at locations where deeper section is exposed.\u003cbr/\u003e\u003cbr/\u003eThis survey will include long profiles and detailed grids over potential drill sites. Survey lines will be tied to existing geophysical profiles and DSDP 270. A recent event that makes this plan timely is the calving of giant iceberg B-15 (in March, 2000) and others from the ice front in the eastern Ross Sea. This new calving event and one in 1987 have exposed 16,000 square kilometers of seafloor that had been covered by ice shelf for decades and is not explored. Newly exposed territory can now be mapped by modern geophysical methods. This project will map geological structure and stratigraphy below unconformity RSU6 farther south and east, study the place of Roosevelt Island in the Ross Sea rifting history, and determine subsidence history during Late Cenozoic time (post RSU6) in the far south and east. Finally the project will observe present day sedimentary processes beneath the ice shelf in the newly exposed areas.", "east": 179.99554, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": true, "keywords": "R/V NBP", "locations": null, "north": -75.91667, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Bartek, Louis; Luyendyk, Bruce P.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.58528, "title": "Collaborative Research: Antarctic Cretaceous-Cenozoic Climate, Glaciation, and Tectonics: Site surveys for drilling from the edge of the Ross Ice Shelf", "uid": "p0000425", "west": -179.99786}, {"awards": "9418153 Domack, Eugene", "bounds_geometry": "POLYGON((-70.90663 -52.3574,-69.956557 -52.3574,-69.006484 -52.3574,-68.056411 -52.3574,-67.106338 -52.3574,-66.156265 -52.3574,-65.206192 -52.3574,-64.256119 -52.3574,-63.306046 -52.3574,-62.355973 -52.3574,-61.4059 -52.3574,-61.4059 -53.843373,-61.4059 -55.329346,-61.4059 -56.815319,-61.4059 -58.301292,-61.4059 -59.787265,-61.4059 -61.273238,-61.4059 -62.759211,-61.4059 -64.245184,-61.4059 -65.731157,-61.4059 -67.21713,-62.355973 -67.21713,-63.306046 -67.21713,-64.256119 -67.21713,-65.206192 -67.21713,-66.156265 -67.21713,-67.106338 -67.21713,-68.056411 -67.21713,-69.006484 -67.21713,-69.956557 -67.21713,-70.90663 -67.21713,-70.90663 -65.731157,-70.90663 -64.245184,-70.90663 -62.759211,-70.90663 -61.273238,-70.90663 -59.787265,-70.90663 -58.301292,-70.90663 -56.815319,-70.90663 -55.329346,-70.90663 -53.843373,-70.90663 -52.3574))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002066", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9903"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9418153 This award supports a program aimed at providing research experiences to a broad range of undergraduate students. The program sill allow for active participation by undergraduate students in ongoing marine geologic research in Antarctica. Students will be recruited from institutions across the United States and will participate in a preparatory seminar on Antarctic science prior to the field season. This program will integrate undergraduate participation with existing marine geology and geophysics projects aboard either of the two United States Antarctic Program research vessels, the RV Polar Duke and the RVIB Nathaniel B. Palmer. Research topics will be related to the stratigraphy and/or evolution of the Antarctic continental margin, topics of increasing importance to both Antarctic and global geology. Students will have a full year following their field experience to conduct follow-up research via a senior thesis. This program is intended to provide better educational experiences to promising undergraduate students and to stimulate those students to pursue advanced degrees in geology and geophysics. ***", "east": -61.4059, "geometry": "POINT(-66.156265 -59.787265)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.3574, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Domack, Eugene Walter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -67.21713, "title": "Undergraduate Research Initiative: Antarctic Marine Geology and Geophysics", "uid": "p0000623", "west": -70.90663}, {"awards": "9527876 Anderson, John", "bounds_geometry": "POLYGON((-179.9996 -70.29238,-143.99968 -70.29238,-107.99976 -70.29238,-71.99984 -70.29238,-35.99992 -70.29238,0 -70.29238,35.99992 -70.29238,71.99984 -70.29238,107.99976 -70.29238,143.99968 -70.29238,179.9996 -70.29238,179.9996 -71.048723,179.9996 -71.805066,179.9996 -72.561409,179.9996 -73.317752,179.9996 -74.074095,179.9996 -74.830438,179.9996 -75.586781,179.9996 -76.343124,179.9996 -77.099467,179.9996 -77.85581,143.99968 -77.85581,107.99976 -77.85581,71.99984 -77.85581,35.99992 -77.85581,0 -77.85581,-35.99992 -77.85581,-71.99984 -77.85581,-107.99976 -77.85581,-143.99968 -77.85581,-179.9996 -77.85581,-179.9996 -77.099467,-179.9996 -76.343124,-179.9996 -75.586781,-179.9996 -74.830438,-179.9996 -74.074095,-179.9996 -73.317752,-179.9996 -72.561409,-179.9996 -71.805066,-179.9996 -71.048723,-179.9996 -70.29238))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002125", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9801"}, {"dataset_uid": "002067", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9902"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Anderson OPP 9527876 Abstract This award supports continuation of a long term investigation of the continental shelf sediments that is aimed at examining the configuration of the West Antarctic Ice Sheet during the last glacial maximum, the events and mechanisms involved in its retreat, and the timing of retreat. The project involves: 1) characterizing variations in the ice sheet grounding zone in a latitudinal transect extending from Ross Sea to Bransfield Basin, 2) reconstructing conditions at the ice/bed interface prior to and after ice sheet retreat, and 3) radiometrically dating ice sheet retreat along this transect. Detailed sea floor imagery (multibeam and deep-tow side-scan sonar), high resolution seismic reflection profiles, and sediment cores will be used to map and characterize prior grounding zones. Of particular concern are features that indicate the amount and organization (channelization) of basal meltwater and the extent of bed deformation that occurred in different ice streams. The timing of ice sheet retreat provides information about the link between Northern and Southern hemisphere ice expansion, and the role of eustasy in ice sheet decoupling. This research should lead to better predictive models to determine which ice streams are most unstable and likely, therefore, to serve as Oweak linksO in the long term behavior of West Antarctic Ice Sheet.", "east": 179.9996, "geometry": "POINT(0 -89.999)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -70.29238, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, John", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.85581, "title": "Mechanism and Timing of West Antarctic Ice Sheet Retreat at the End of the Last Glacial Maximum", "uid": "p0000624", "west": -179.9996}, {"awards": "0338101 Padman, Laurence", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0603", "datasets": [{"dataset_uid": "002614", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0603", "url": "https://www.rvdata.us/search/cruise/NBP0603"}, {"dataset_uid": "002615", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0603", "url": "https://www.rvdata.us/search/cruise/NBP0603"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The Larsen Ice Shelf is the third largest ice shelf in Antarctica and has continued a pattern of catastrophic decay since the mid 1990\u0027s. The proposed marine geologic work at the Larsen Ice Shelf builds upon our previous NSF-OPP funding and intends to test the working hypothesis that the Larsen B Ice Shelf system has been a stable component of Antarctica\u0027s glacial system since it formed during rising sea levels 10,000 years BP. This conclusion, if supported by observations from our proposed work, is an important first step in establishing the uniqueness and consequences of rapid regional warming currently taking place across the Peninsula. Our previous work in the Larsen A and B embayments has allowed us to recognize the signature of past ice shelf fluctuations and their impact on the oceanographic and biologic environments. We have also overcome many of the limitations of standard radiocarbon dating in Antarctic marine sequences by using variations in the strength of the earth\u0027s magnetic field for correlation of sediment records and by using specific organic compounds (instead of bulk sediment) for radiocarbon dating. We intend to pursue these analytical advances and extend our sediment core stratigraphy to areas uncovered by the most recent collapse of the Larsen B Ice Shelf and areas immediately adjacent to the Larsen C Ice Shelf. In addition to the core recovery program, we intend to utilize our unique access to the ice shelf front to continue our observations of the snow/ice stratigraphy, oceanographic character, and ocean floor character. Sediment traps will also be deployed in order to measure the input of debris from glaciers that are now surging in response to the ice shelf collapse. This proposal is a multi-institutional, international (USAP, Italy, and Canada) effort that combines the established expertise in a variety of disciplines and integrates the research plan into the educational efforts of primarily undergraduate institutions but including some graduate education. This is a three-year project with field seasons planned with flexibility in order to accommodate schedules for the RVIB L.M. Gould. The Antarctic Peninsula is undergoing greater warming than almost anywhere on Earth, perhaps associated with human-induced greenhouse effects. Our proposed work contributes to understanding of these changes where they are occurring first and with greatest magnitude and impact upon the environment.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Padman, Laurence; Domack, Eugene Walter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Paleohistory of the Larsen Ice Shelf: Phase II", "uid": "p0000827", "west": null}, {"awards": "9614201 Gowing, Marcia", "bounds_geometry": "POLYGON((-180 -43.56536,-144 -43.56536,-108 -43.56536,-72 -43.56536,-36 -43.56536,0 -43.56536,36 -43.56536,72 -43.56536,108 -43.56536,144 -43.56536,180 -43.56536,180 -46.976149,180 -50.386938,180 -53.797727,180 -57.208516,180 -60.619305,180 -64.030094,180 -67.440883,180 -70.851672,180 -74.262461,180 -77.67325,144 -77.67325,108 -77.67325,72 -77.67325,36 -77.67325,0 -77.67325,-36 -77.67325,-72 -77.67325,-108 -77.67325,-144 -77.67325,-180 -77.67325,-180 -74.262461,-180 -70.851672,-180 -67.440883,-180 -64.030094,-180 -60.619305,-180 -57.208516,-180 -53.797727,-180 -50.386938,-180 -46.976149,-180 -43.56536))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002003", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9901"}, {"dataset_uid": "002193", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9508"}, {"dataset_uid": "002110", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9803"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9614201 Costa Sea ice forms an extensive habitat in the Southern Ocean. Reports dating from the earliest explorations of Antarctica have described high concentrations of algae associated with sea-ice, suggesting that the ice must be an important site of production and biological activity. The magnitude and importance of ice-based production is difficult to estimate largely because the spatial and temporal distributions of ice communities have been examined in only a few regions, and the processes controlling production and community development in ice are still superficially understood. This study will examine sea ice communities in the Ross Sea region of Antarctica in conjunction with a studies of ice physics and remote sensing. The specific objectives of the study are: 1) to relate the overall distribution of ice communities in the Ross Sea to specific habitats that are formed as the result of ice formation and growth processes; 2) to study the initial formation of sea ice to document the incorporation and survival of organisms, in particular to examine winter populations within \"snow-ice\" layers to determine if there is a seed population established at the time of surface flooding; 3) to sample summer communities to determine the extent that highly productive \"snow-ice\" and \"freeboard\" communities develop in the deep water regions of the Ross Sea; 4) and to collect basic data on the biota, activity, and general physical and chemical characteristics of the ice assemblages, so that this study contributes to the general understanding of the ecology of the ice biota in pack ice regions.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56536, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gowing, Marcia; Garrison, David; Jeffries, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.67325, "title": "Ecological Studies of Sea Ice Communities in the Ross Sea, Antarctica", "uid": "p0000633", "west": -180.0}, {"awards": "0538148 Huber, Bruce", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0801; Processed CurrentMeter Data from the Adare Basin near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1101 ; Processed CurrentMeter Data from the Ross Sea near Antarctica acquired during the Nathaniel B. Palmer expedition NBP0801", "datasets": [{"dataset_uid": "601344", "doi": null, "keywords": "Antarctica; Cape Adare; Mooring; NBP0801; Physical Oceanography; Ross Sea; R/v Nathaniel B. Palmer; Salinity; Southern Ocean; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed CurrentMeter Data from the Ross Sea near Antarctica acquired during the Nathaniel B. Palmer expedition NBP0801", "url": "https://www.usap-dc.org/view/dataset/601344"}, {"dataset_uid": "002647", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0801", "url": "https://www.rvdata.us/search/cruise/NBP0801"}, {"dataset_uid": "001517", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0801"}, {"dataset_uid": "601343", "doi": null, "keywords": "Antarctica; Mooring; NBP1101; Ross Sea; Salinity; Southern Ocean; Temperature", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": null, "title": "Processed CurrentMeter Data from the Adare Basin near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1101 ", "url": "https://www.usap-dc.org/view/dataset/601343"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "An array of moorings will be deployed and maintained east of Cape Adare, Antarctica, at the northwestern corner of the Ross Sea to observe the properties of Antarctic Bottom Water (AABW) exiting the Ross Sea. This location has been identified from recent studies as an ideal place to make such measurements. Antarctic Bottom Water has the highest density of the major global water masses, and fills the deepest parts of the world\u0027s oceans. Because it obtains many of its characteristics during its contact with the atmosphere and with glacial ice along the continental margins of Antarctica, it is expected that changes in newly-formed AABW may represent an effective indicator for abrupt climate change. The heterogeneous nature of the source regions around Antarctica complicates the observation of newly-formed AABW properties. The two most important source regions for AABW are within the Weddell and the Ross Seas, with additional sources drawn from the east Antarctic margins. In the northwestern Weddell Sea, several programs have been undertaken in the last decade to monitor the long term variability of Weddell Sea Deep and Bottom Water, precursors of AABW originating from the Weddell Sea, however no such systematic efforts have yet been undertaken to make longterm measurements of outflow from the Ross Sea. The proposed study will significantly improve our knowledge of the long term variability in the outflow of deep and bottom water from the Ross Sea, and will provide the beginnings of a long-term monitoring effort which ultimately will allow detection of changes in the ocean in the context of global climate change. When joined with similar efforts ongoing in the Weddell Sea, long-term behavior and possible coupling of these two important sources of the ocean\u0027s deepest water mass can be examined in detail.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Caron, Bruce", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Cape Adare Long-term Mooring (CALM)", "uid": "p0000838", "west": null}, {"awards": "0125480 Manley, Patricia", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0602A", "datasets": [{"dataset_uid": "001571", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0602A"}, {"dataset_uid": "002618", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0602A", "url": "https://www.rvdata.us/search/cruise/NBP0602A"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this \"demonstration cruise\" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the \"Greenhouse-Icehouse\" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program\u0027s technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the \"no man\u0027s land\" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program\u0027s vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ROCK CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, John", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: SHALDRIL - A Demonstration Drilling Cruise to the James Ross Basin", "uid": "p0000830", "west": null}, {"awards": "9118439 Karl, David", "bounds_geometry": "POLYGON((-76.8432 -52.3533,-74.99221 -52.3533,-73.14122 -52.3533,-71.29023 -52.3533,-69.43924 -52.3533,-67.58825 -52.3533,-65.73726 -52.3533,-63.88627 -52.3533,-62.03528 -52.3533,-60.18429 -52.3533,-58.3333 -52.3533,-58.3333 -54.01689,-58.3333 -55.68048,-58.3333 -57.34407,-58.3333 -59.00766,-58.3333 -60.67125,-58.3333 -62.33484,-58.3333 -63.99843,-58.3333 -65.66202,-58.3333 -67.32561,-58.3333 -68.9892,-60.18429 -68.9892,-62.03528 -68.9892,-63.88627 -68.9892,-65.73726 -68.9892,-67.58825 -68.9892,-69.43924 -68.9892,-71.29023 -68.9892,-73.14122 -68.9892,-74.99221 -68.9892,-76.8432 -68.9892,-76.8432 -67.32561,-76.8432 -65.66202,-76.8432 -63.99843,-76.8432 -62.33484,-76.8432 -60.67125,-76.8432 -59.00766,-76.8432 -57.34407,-76.8432 -55.68048,-76.8432 -54.01689,-76.8432 -52.3533))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002292", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9302"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The annual advance and retreat of pack ice may be the major physical determinant of spatial/temporal changes in the structure and function of antarctic marine communities. Interannual cycles and/or trends in the annual extent of pack ice may also have significant effects on all levels of the food web, from total annual primary production to breeding success in seabirds. Historical records indicate a 6 to 8 year cycle in the maximum extent of pack ice in the winter. During this decade winters were colder in 1980 and 1981, and again in 1986 and 1987. In order to understand the interactions between pack ice and ecosystem dynamics, especially the influences of the well- documented interannual variability in ice cover on representative populations, a long-term ecological research (LTER) site has been established in the Antarctic Peninsula region near Palmer Station. The LTER project, will conduct comprehensive measurements of ice-dominated ecosystems in this region with a focus on primary production, krill populations and swarms and seabirds. A primary emphasis will be placed on the development of ecosystem models that will provide a predictive capability for issues related to global environmental change. This proposal will add to the existing LTER project detailed studies of the biogeochemical cycling of carbon and associated bioelements. The microbiology and carbon flux component of LTER will provide measurements of a suite of core parameters relevant to the carbon cycle and will test several hypotheses pertaining to carbon flux, including bacterial productivity and nutrient regeneration.", "east": -58.3333, "geometry": "POINT(-67.58825 -60.67125)", "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.3533, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Karl, David; Ross, Robin Macurda", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": "LTER", "south": -68.9892, "title": "Long-term Ecological Research (LTER) on the Antarctic Marine Ecosystem: Microbiology and Carbon Flux", "uid": "p0000651", "west": -76.8432}, {"awards": "9814041 Austin, Jr., James", "bounds_geometry": "POLYGON((-70.90616 -52.35281,-69.390587 -52.35281,-67.875014 -52.35281,-66.359441 -52.35281,-64.843868 -52.35281,-63.328295 -52.35281,-61.812722 -52.35281,-60.297149 -52.35281,-58.781576 -52.35281,-57.266003 -52.35281,-55.75043 -52.35281,-55.75043 -53.463301,-55.75043 -54.573792,-55.75043 -55.684283,-55.75043 -56.794774,-55.75043 -57.905265,-55.75043 -59.015756,-55.75043 -60.126247,-55.75043 -61.236738,-55.75043 -62.347229,-55.75043 -63.45772,-57.266003 -63.45772,-58.781576 -63.45772,-60.297149 -63.45772,-61.812722 -63.45772,-63.328295 -63.45772,-64.843868 -63.45772,-66.359441 -63.45772,-67.875014 -63.45772,-69.390587 -63.45772,-70.90616 -63.45772,-70.90616 -62.347229,-70.90616 -61.236738,-70.90616 -60.126247,-70.90616 -59.015756,-70.90616 -57.905265,-70.90616 -56.794774,-70.90616 -55.684283,-70.90616 -54.573792,-70.90616 -53.463301,-70.90616 -52.35281))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001987", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0002"}, {"dataset_uid": "001810", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0007A"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to study the deep crustal structure of the Bransfield Strait region. Bransfield Strait, in the northern Antarctic Peninsula, is one of a small number of modern basins that may be critical for understanding ancient mountain-building processes. The Strait is an actively-extending marginal basin in the far southeast Pacific, between the Antarctic Peninsula and the South Shetland Islands, an inactive volcanic arc. Widespread crustal extension, accompanied by volcanism along the Strait\u0027s axis, may be associated with slow underthrusting of oceanic crust at the South Shetland Trench; similar \"back-arc\" extension occurred along the entire Pacific margin (now western South America/West Antarctica) of the supercontinent known as Gondwanaland during the Jurassic-Early Cretaceous. Mid-Cretaceous deformation of these basins some 100 million years ago initiated uplift of the Andes. By understanding the deep structure and evolution of Bransfield rift, it should be possible to evaluate the crustal precursor to the Andes, and thereby understand more fully the early evolution of this globally important mountain chain.\u003cbr/\u003e\u003cbr/\u003eYears of international earth sciences research in Bransfield Strait has produced consensus on important aspects of its geologic environment: (1) It is probably a young (probably ~4 million years old) rift in preexisting Antarctic Peninsula crust; continued stretching of this crust results in complex fault patterns and associated volcanism. The volcanism, high heat flow, and mapped crustal trends are all consistent with the basin\u0027s continuing evolution as a rift; (2) The volcanism, which is recent and continuing, occurs along a \"neovolcanic\" zone centralized along the basin\u0027s axis. Multichannel seismic data collected aboard R/V Maurice Ewing in 1991 illustrate the following basin-wide characteristics of Bransfield Strait - a) widespread extension and faulting, b) the rise of crustal diapirs or domes associated with flower-shaped normal-fault structures, and c) a complicated system of fault-bounded segments across strike. The geophysical evidence also suggests NE-to-SW propagation of the rift, with initial crustal inflation/doming followed by deflation/subsidence, volcanism, and extension along normal faults.\u003cbr/\u003e\u003cbr/\u003eAlthough Bransfield Strait exhibits geophysical and geologic evidence for extension and volcanism, continental crust fragmentation does not appear to have gone to completion in this \"back-arc\" basin and ocean crust is not yet being generated. Instead, Bransfield rift lies near the critical transition from intracontinental rifting to seafloor-spreading. The basin\u0027s asymmetry, and seismic evidence for shallow intracrustal detachment faulting, suggest that it may be near one end-member of the spectrum of models proposed for continental break-up. Therefore, this basin is a \"natural lab\" for studying diverse processes involved in forming continental margins.\u003cbr/\u003e\u003cbr/\u003eUnderstanding Bransfield rift\u0027s deep crustal structure is the key to resolving its stage of evolution, and should also provide a starting point for models of Andean mountain-building. This work will define the deep structure by collecting and analyzing high-quality, high-density ocean bottom seismometer (OBS) profiles both along and across the Strait\u0027s strike. Scientific objectives are as follows: (1) to develop a detailed seismic velocity model for this rift; (2) to calibrate velocity structure and crustal thickness changes associated with presumed NE-to-SW rift propagation, as deduced from the multichannel seismic interpretations; (3) to document the degree to which deep velocity structure corresponds to along- and across-strike crustal segmentation; and (4) to assess structural relationships between the South Shetland Islands \"arc\" and Bransfield rift.\u003cbr/\u003e\u003cbr/\u003eThe proposed OBS data, integrated with interpretations of both Ewing profiles and those from other high-quality geophysical coverage in Bransfield Strait, will complement ongoing deep seismic analysis of Antarctic Peninsula crust to the southwest and additional OBS monitoring for deep earthquakes, in order to understand the complex plate tectonic evolution of this region.", "east": -55.75043, "geometry": "POINT(-63.328295 -57.905265)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.35281, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Austin, James; Austin, James Jr.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -63.45772, "title": "The Young Marginal Basin as a Key to Understanding the Rift-Drift Transition and Andean Orogenesis: OBS Refraction Profiling for Crustal Structure in Bransfield Strait", "uid": "p0000615", "west": -70.90616}, {"awards": "0542111 Lonsdale, Darcy; 0542456 Caron, David", "bounds_geometry": "POLYGON((-179.9999 -43.5663,-143.99993 -43.5663,-107.99996 -43.5663,-71.99999 -43.5663,-36.00002 -43.5663,-0.000050000000016 -43.5663,35.99992 -43.5663,71.99989 -43.5663,107.99986 -43.5663,143.99983 -43.5663,179.9998 -43.5663,179.9998 -46.99537,179.9998 -50.42444,179.9998 -53.85351,179.9998 -57.28258,179.9998 -60.71165,179.9998 -64.14072,179.9998 -67.56979,179.9998 -70.99886,179.9998 -74.42793,179.9998 -77.857,143.99983 -77.857,107.99986 -77.857,71.99989 -77.857,35.99992 -77.857,-0.000049999999987 -77.857,-36.00002 -77.857,-71.99999 -77.857,-107.99996 -77.857,-143.99993 -77.857,-179.9999 -77.857,-179.9999 -74.42793,-179.9999 -70.99886,-179.9999 -67.56979,-179.9999 -64.14072,-179.9999 -60.71165,-179.9999 -57.28258,-179.9999 -53.85351,-179.9999 -50.42444,-179.9999 -46.99537,-179.9999 -43.5663))", "dataset_titles": "Do Crustacean Zooplankton Play a Pivotal Role in Structuring Heterotrophic Plankton Communities in the Ross Sea?; Expedition Data; NBP0802 data; Processed CurrentMeter Data from the Ross Sea near Antarctica acquired during the Nathaniel B. Palmer expedition NBP0801", "datasets": [{"dataset_uid": "601344", "doi": null, "keywords": "Antarctica; Cape Adare; Mooring; NBP0801; Physical Oceanography; Ross Sea; R/v Nathaniel B. Palmer; Salinity; Southern Ocean; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed CurrentMeter Data from the Ross Sea near Antarctica acquired during the Nathaniel B. Palmer expedition NBP0801", "url": "https://www.usap-dc.org/view/dataset/601344"}, {"dataset_uid": "600059", "doi": "10.15784/600059", "keywords": "Antarctica; Biota; Crustacea; Oceans; Phytoplankton; Ross Sea; Southern Ocean", "people": "Lonsdale, Darcy", "repository": "USAP-DC", "science_program": null, "title": "Do Crustacean Zooplankton Play a Pivotal Role in Structuring Heterotrophic Plankton Communities in the Ross Sea?", "url": "https://www.usap-dc.org/view/dataset/600059"}, {"dataset_uid": "000122", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0802 data", "url": "https://www.rvdata.us/search/cruise/NBP0802"}, {"dataset_uid": "001517", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0801"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Recent studies of marine ecosystems show conflicting evidence for trophic cascades, and in particular the relative strength of the crustacean zooplankton-phytoplankton link. The Ross Sea is a natural laboratory for investigating this apparent conflict. It is a site of seasonally high abundances of phytoplankton, characterized by regions of distinct phytoplankton taxa; the southcentral polynya is strongly dominated by the colony-forming prymnesiophyte Phaeocystis antarctica, while coastal regions of this sea are typically dominated by diatoms or flagellate species. Recent studies indicate that, while the south-central polynya exhibits a massive phytoplankton bloom, the poor food quality of P. antarctica for many crustacean zooplankton prevents direct utilization of much of this phytoplankton bloom. Rather, evidence suggests that indirect utilization of this production may be the primary mechanism by which carbon and energy become available to those higher trophic levels. Specifically, we hypothesize that nano and microzooplankton constitute an important food source for crustacean zooplankton (largely copepods and juvenile euphausiids) during the summer period in the Ross Sea where the phytoplankton assemblage is dominated by the prymnesiophyte. In turn, we also hypothesize that predation by copepods (and other Crustacea) controls and structures the species composition of these protistan assemblages. We will occupy stations in the south-central Ross Sea Polynya (RSP) and Terra Nova Bay (TNB) during austral summer to test these hypotheses. We hypothesize that the diatom species that dominate the phytoplankton assemblage in TNB constitute a direct source of nutrition to herbivorous/omnivorous zooplankton (relative to the situation in the south-central RSP). That is, the contribution of heterotrophic protists to crustacean diets will be reduced in TNB. Our research will address fundamental gaps in our knowledge of food web structure and trophic cascades, and provide better understanding of the flow of carbon and energy within the biological community of this perennially cold sea. The PIs will play active roles in public education (K-12) via curriculum development (on Antarctic biology) and teacher trainer activities in the Centers for Ocean Science Education Excellence (COSEE-West), an innovative, NSF-funded program centered at USC and UCLA.", "east": 179.9998, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": true, "keywords": "R/V NBP", "locations": null, "north": -43.5663, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Lonsdale, Darcy; Caron, Bruce", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -77.857, "title": "Collaborative Research: Do Crustacean Zooplankton Play a Pivotal Role in Structuring Heterotrophic Plankton Communities in the Ross Sea?", "uid": "p0000520", "west": -179.9999}, {"awards": "9416989 Cande, Steven", "bounds_geometry": "POLYGON((-179.9998 -46.00095,-143.99984 -46.00095,-107.99988 -46.00095,-71.99992 -46.00095,-35.99996 -46.00095,0 -46.00095,35.99996 -46.00095,71.99992 -46.00095,107.99988 -46.00095,143.99984 -46.00095,179.9998 -46.00095,179.9998 -49.185793,179.9998 -52.370636,179.9998 -55.555479,179.9998 -58.740322,179.9998 -61.925165,179.9998 -65.110008,179.9998 -68.294851,179.9998 -71.479694,179.9998 -74.664537,179.9998 -77.84938,143.99984 -77.84938,107.99988 -77.84938,71.99992 -77.84938,35.99996 -77.84938,0 -77.84938,-35.99996 -77.84938,-71.99992 -77.84938,-107.99988 -77.84938,-143.99984 -77.84938,-179.9998 -77.84938,-179.9998 -74.664537,-179.9998 -71.479694,-179.9998 -68.294851,-179.9998 -65.110008,-179.9998 -61.925165,-179.9998 -58.740322,-179.9998 -55.555479,-179.9998 -52.370636,-179.9998 -49.185793,-179.9998 -46.00095))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002148", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9702"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9416989 Cande There is a significant misfit, ranging from 50 to 250 kms, of magnetic anomalies 13, 18, and 20 along the section of the Southeast Indian Ridge east of the Balleny fracture zone. This project will survey the critical plate boundaries and relevant magnetic anomalies in the South Tasman Sea, Emerald Basin and north of the Ross Sea embayment that will better constrain the history of the this plate motion. Data collected will be used to test the hypothesis that the Antarctic side of the ridge acted as a separate plate, attached to Marie Byrd Land, and that these anomalies indirectly indicate motion between East and West Antarctica between anomalies 24 and 13 time. Surveys will be conducted on the R/V W M Ewing in the Tasman Sea, and on the R/V N B Palmer north of the Ross Sea embayment. ***", "east": 179.9998, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -46.00095, "nsf_funding_programs": null, "paleo_time": null, "persons": "Cande, Steven", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.84938, "title": "Collaborative Research: Early Tertiary Tectonic Evolution of the Pacific-Australia-Antarctic Plate Circuit", "uid": "p0000632", "west": -179.9998}, {"awards": "9119683 Anderson, John", "bounds_geometry": "POLYGON((-179.999 -72.1543,-143.9991 -72.1543,-107.9992 -72.1543,-71.9993 -72.1543,-35.9994 -72.1543,0.000500000000017 -72.1543,36.0004 -72.1543,72.0003 -72.1543,108.0002 -72.1543,144.0001 -72.1543,180 -72.1543,180 -72.72384,180 -73.29338,180 -73.86292,180 -74.43246,180 -75.002,180 -75.57154,180 -76.14108,180 -76.71062,180 -77.28016,180 -77.8497,144.0001 -77.8497,108.0002 -77.8497,72.0003 -77.8497,36.0004 -77.8497,0.000499999999988 -77.8497,-35.9994 -77.8497,-71.9993 -77.8497,-107.9992 -77.8497,-143.9991 -77.8497,-179.999 -77.8497,-179.999 -77.28016,-179.999 -76.71062,-179.999 -76.14108,-179.999 -75.57154,-179.999 -75.002,-179.999 -74.43246,-179.999 -73.86292,-179.999 -73.29338,-179.999 -72.72384,-179.999 -72.1543))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002258", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9401"}, {"dataset_uid": "002241", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9501"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Marine geological and geophysical studies of the Ross Sea and Weddell Sea continental shelves provide evidence that the ice sheet grounded near the shelf edge in these areas during the late Wisconsinan, and that the retreat of the ice sheet to its present position was rapid and probably episodic. This Award supports a project which will establish the most recent (late Wisconsin- Holocene) history of ice sheet advance and retreat in Ross Sea. The objectives include: 1) reconstruction the late Wisconsin paleodrainage regime, including ice stream divides; 2) reconstruction of former grounding zone positions; 3) constraint of the timing of ice sheet retreat from the shelf; and 4) acquisition of geophysical, sedimentological, and paleontological data which may provide indicators the environmental factors that may have influenced to ice sheet retreat. This is a joint effort between Rice University, the University of Colorado, and Hamilton College. The project involves experts in a wide variety of fields, and will interface with glaciologists, physical oceanographers and climatologists who will address the problem of ice sheet stability and the record of climatic and glaciological change.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -72.1543, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, John", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.8497, "title": "Geologic Record of Late Wisconsinan/Holocene Ice Sheet Advance and Retreat from Ross Sea", "uid": "p0000641", "west": -179.999}, {"awards": "9316035 Gowing, Marcia", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP9406", "datasets": [{"dataset_uid": "002252", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9406"}, {"dataset_uid": "002592", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP9406", "url": "https://www.rvdata.us/search/cruise/NBP9406"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. The focus of this proposal is the role of microzooplankton in controlling the production and fate of carbon during the two types of blooms. Objectives are: 1) to determine biomass, abundance, size and selected species composition of primary producer assemblages, 2) to determine similar features of nano- and microplanktonic heterotrophic assemblages, 3) to measure total community grazing on heterotrophic bacteria and phytoplankton, 4) to examine which grazers are the major herbivores and bacterivores, and 5) to measure the contribution of microzooplankton and mesozooplankton egesta, sinking of algal cells and colonies, and sinking of protozoan assemblages associated with detritus to the total carbon flux from the euphotic zone through 250 m depth. Water samples for abundance and biomass determinations will be taken and samples will be examined with epifluorescence microscopy. Grazing rates will be measured using the dilution grazing technique and the dual-isotope radiolabeling single cell method. Carbon fluxes will be determined on sinking material collected with particle interceptor traps at the base of the euphotic zone and two deeper depths, using microscopical analysis . An understanding of these processes and other fundamental processes studied by collaborating investigators will contribute to the understanding of the role of the Southern Ocean in present, past and predicted future sequestration of carbon, as well as in other global elemental cycles.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Bloom Dynamics and Food Web Structure in the Ross Sea: Role of Microzooplankton in Controlling Production", "uid": "p0000811", "west": null}, {"awards": "0440959 Cande, Steven", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0701", "datasets": [{"dataset_uid": "002644", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0701", "url": "https://www.rvdata.us/search/cruise/NBP0701"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This work will perform a marine geophysical survey of sea floor spreading off Cape Adare, Antarctica. Magnetic, gravity, swath bathymetry and multi-channel seismic data will be acquired from the southern end of the Adare Basin to the northern parts of the Northern Basin and Central Trough in the Ross Embayment. Previous surveys documented 170 km of regional extension between forty-three and twenty-six million years ago, which resulted in some seafloor spreading in the Adare Basin. However, the relationship of Adare Basin spreading to the overall extension and the southward continental basins of the Ross Embayment has not been established. This relationship is critical to understanding the tectonic evolution of East and West Antarctica and linking Pacific plate motions to the rest of the world. The study will also offer unique insight into rifting processes by studying the transition of rifting between oceanic and continental lithosphere. In terms of broader impacts, this project will support two graduate students and field research experience for undergraduates. The project also involves cooperation between scientists from the US, Australia, New Zealand and Japan.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ROCK CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Cande, Steven", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: The Connection Between Mid-Cenozoic Seafloor Spreading and the Western Ross Sea Embayment", "uid": "p0000835", "west": null}, {"awards": "0338164 Sedwick, Peter", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0601", "datasets": [{"dataset_uid": "002619", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0601", "url": "https://www.rvdata.us/search/cruise/NBP0601"}, {"dataset_uid": "001580", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0601"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. \u003cbr/\u003eThis project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ditullio, Giacomo", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Interactive Effects of Iron, Light and CO2 on Phytoplankton Community Dynamics in the Ross Sea", "uid": "p0000831", "west": null}, {"awards": "9316710 Bartek, Louis", "bounds_geometry": "POLYGON((-179.9993 -75.77948,-143.99945 -75.77948,-107.9996 -75.77948,-71.99975 -75.77948,-35.9999 -75.77948,-0.000049999999987 -75.77948,35.9998 -75.77948,71.99965 -75.77948,107.9995 -75.77948,143.99935 -75.77948,179.9992 -75.77948,179.9992 -76.012273,179.9992 -76.245066,179.9992 -76.477859,179.9992 -76.710652,179.9992 -76.943445,179.9992 -77.176238,179.9992 -77.409031,179.9992 -77.641824,179.9992 -77.874617,179.9992 -78.10741,143.99935 -78.10741,107.9995 -78.10741,71.99965 -78.10741,35.9998 -78.10741,-0.000050000000016 -78.10741,-35.9999 -78.10741,-71.99975 -78.10741,-107.9996 -78.10741,-143.99945 -78.10741,-179.9993 -78.10741,-179.9993 -77.874617,-179.9993 -77.641824,-179.9993 -77.409031,-179.9993 -77.176238,-179.9993 -76.943445,-179.9993 -76.710652,-179.9993 -76.477859,-179.9993 -76.245066,-179.9993 -76.012273,-179.9993 -75.77948))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002168", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9601"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award supports a collaborative marine geological and geophysical project between the University of California, Santa Barbara, and the University of Alabama to study the glacial and tectonic history of the eastern Ross Sea and the Marie Byrd Land margin of West Antarctica. The goals of the project are (1) to conduct seismic imaging and piston coring to begin unraveling the history of the West Antarctic ice Sheet as recorded in the recent sediments of the continental shelf of the region, and (2) to acquire seismic images of the acoustic basement beneath the Cenozoic glacial deposits toward an understanding of the relationship between rift structure of the continental crust and Cenozoic glacial deposits of the region. This research will result in bathymetric, structural, sediment isopach, gravity and magnetic maps of the eastern Ross Sea and the Marie Byrd Land margin. This information will be integrated into an interpretation of the major glacial and structural features of the region. This project will result in a better understanding of the glacio-marine stratigraphy and glacial history of the eastern Ross Sea and Marie Byrd Land margin and, consequently, it will represent a significant contribution to the goals of the West Antarctic Ice Sheet initiative.", "east": 179.9992, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -75.77948, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Bartek, Louis; Luyendyk, Bruce P.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.10741, "title": "Collaborative Research: Glacial Marine Stratigraphy in the Eastern Ross Sea and Western Marie Byrd Land, and Shallow Structure of the West Antarctic Rift", "uid": "p0000639", "west": -179.9993}, {"awards": "9815283 Cande, Steven; 9814579 Stock, Joann", "bounds_geometry": "POLYGON((-57.56218 -33.87102,-49.979095 -33.87102,-42.39601 -33.87102,-34.812925 -33.87102,-27.22984 -33.87102,-19.646755 -33.87102,-12.06367 -33.87102,-4.480585 -33.87102,3.1025 -33.87102,10.685585 -33.87102,18.26867 -33.87102,18.26867 -35.4505,18.26867 -37.02998,18.26867 -38.60946,18.26867 -40.18894,18.26867 -41.76842,18.26867 -43.3479,18.26867 -44.92738,18.26867 -46.50686,18.26867 -48.08634,18.26867 -49.66582,10.685585 -49.66582,3.1025 -49.66582,-4.480585 -49.66582,-12.06367 -49.66582,-19.646755 -49.66582,-27.22984 -49.66582,-34.812925 -49.66582,-42.39601 -49.66582,-49.979095 -49.66582,-57.56218 -49.66582,-57.56218 -48.08634,-57.56218 -46.50686,-57.56218 -44.92738,-57.56218 -43.3479,-57.56218 -41.76842,-57.56218 -40.18894,-57.56218 -38.60946,-57.56218 -37.02998,-57.56218 -35.4505,-57.56218 -33.87102))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001873", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0102"}, {"dataset_uid": "001699", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304"}, {"dataset_uid": "001746", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0207"}, {"dataset_uid": "002042", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9908"}, {"dataset_uid": "001963", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0007B"}, {"dataset_uid": "001742", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0209"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided jointly by the Antarctic Geology and Geophysics Program of the Office of Polar Programs and the Marine Geology and Geophysics Program of the Division of Ocean Sciences, supports research to develop improved plate rotation models for the Southwest Pacific region (between the Pacific, Antarctic, and Australian plates, and the continental fragments of New Zealand, West Antarctica, Iselin Bank, East Antarctica, and Australia). The improved rotation parameters will be used to address tectonic problems related to motion between East and West Antarctica, and in particular, the questions of relative drift between major hotspot groups and the controversy regarding a possible missing plate boundary in this region. Previous work has documented NNW-striking mid-Tertiary seafloor spreading magnetic anomalies between East and West Antarctica, representing about 150 km of opening of the Adare Trough, north of the Ross Sea. This is not enough motion to resolve the apparent discrepancy between the plate motions and motions inferred from assuming hotspot fixity. Because this motion between East and West Antarctica corresponds to a very small rotation, it points to the need for determination of finite rotations describing motions of the various plates here with a high degree of accuracy, particularly for older times. This is now possible with the datasets that will be used in this project. \u003cbr/\u003e\u003cbr/\u003eThe work will be accomplished by integrating existing data with analysis and interpretation of other data sets recently made available by Japanese and Italian scientists from their cruises in the region. It will be further augmented by acquisition of new marine geophysical data on selected transits of the R/VIB Nathaniel B. Palmer. Specific objectives of the project include the following:\u003cbr/\u003e\u003cbr/\u003e1) improve the rotation model for mid-Tertiary extension between East and West Antarctica by including the plate boundary between the Pacific and Australia plates directly when calculating Australia-West Antarctica motion,\u003cbr/\u003e2) improve the reconstructions for the Late Cretaceous and Early Tertiary times by including new constraints on several boundaries not previously used in the reconstructions,\u003cbr/\u003e3) address the implications of new rotation models for the question of the fixity of global hotspots,\u003cbr/\u003e4) re-examine the geophysical data from the Western Ross Sea embayment in light of a model for substantial mid-Cenozoic extension.", "east": 18.26867, "geometry": "POINT(-19.646755 -41.76842)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -33.87102, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Cande, Steven; Stock, Joann", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -49.66582, "title": "Collaborative Research: Late Cretaceous and Cenozoic Reconstructions of the Southwest Pacific", "uid": "p0000590", "west": -57.56218}, {"awards": "9615053 Domack, Eugene", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG9802", "datasets": [{"dataset_uid": "002718", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG9802", "url": "https://www.rvdata.us/search/cruise/LMG9802"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Domack: OPP 9615053 Manley: OPP 9615670 Banerjee: OPP 9615695 Dunbar: OPP 9615668 Ishman: OPP 9615669 Leventer: OPP 9714371 Abstract This award supports a multi-disciplinary, multi-institutional effort to elucidate the detailed climate history of the Antarctic Peninsula during the Holocene epoch (the last 10,000 years). The Holocene is an important, but often overlooked, portion of the Antarctic paleoclimatic record because natural variability in Holocene climate on time scales of decades to millennia can be evaluated as a model for our present \"interglacial\" world. This project builds on over ten years of prior investigation into the depositional processes, productivity patterns and climate regime of the Antarctic Peninsula. This previous work identified key locations that contain ultra-high resolution records of past climatic variation. These data indicate that solar cycles operating on multi-century and millennial time scales are important regulators of meltwater production and paleoproductivity. These marine records can be correlated with ice core records in Greenland and Antarctica. This project will focus on sediment dispersal patterns across the Palmer Deep region. The objective is to understand the present links between the modern climatic and oceanographic systems and sediment distribution. In particular, additional information is needed regarding the influence of sea ice on the distribution of both biogenic and terrigenous sediment distribution. Sediment samples will be collected with a variety of grab sampling and coring devices. Analytical work will include carbon-14 dating of surface sediments using accellerator mass spectrometry and standard sedimentologic, micropaleontologic and magnetic granulometric analyses. This multiparameter approach is the most effective way to extract the paleoclimatic signals contained in the marine sediment cores. Two additional objectives are the deployment of sediment traps in front of the Muller Ice Shelf in Lallemand Fjord and seismic reflection work in conjunction with site augmentation funded through the Joint Oceanographic Institute. The goal of sediment trap work is to address whether sand transport and deposition adjacent to the ice shelf calving line results from meltwater or aeolian processes. In addition, the relationship between sea ice conditions and primary productivity will be investigated. The collection of a short series of seismic lines across the Palmer Deep basins will fully resolve the question of depth to acoustic basement. The combination of investigators on this project, all with many years of experience working in high latitude settings, provides an effective team to complete the project in a timely fashion. A combination of undergraduate, graduate and post-graduate students will be involved in all stages of the project so that educational objectives will be met in-tandem with research goals of the project.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Domack, Eugene Walter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Holocene Paleoenvironmental Change Along the Antarctic Peninsula: A Test of the Solar/Bi-Polar Signal", "uid": "p0000869", "west": null}, {"awards": "0125922 Anderson, John", "bounds_geometry": "POLYGON((-69.84264 -52.35215,-68.086508 -52.35215,-66.330376 -52.35215,-64.574244 -52.35215,-62.818112 -52.35215,-61.06198 -52.35215,-59.305848 -52.35215,-57.549716 -52.35215,-55.793584 -52.35215,-54.037452 -52.35215,-52.28132 -52.35215,-52.28132 -53.546701,-52.28132 -54.741252,-52.28132 -55.935803,-52.28132 -57.130354,-52.28132 -58.324905,-52.28132 -59.519456,-52.28132 -60.714007,-52.28132 -61.908558,-52.28132 -63.103109,-52.28132 -64.29766,-54.037452 -64.29766,-55.793584 -64.29766,-57.549716 -64.29766,-59.305848 -64.29766,-61.06198 -64.29766,-62.818112 -64.29766,-64.574244 -64.29766,-66.330376 -64.29766,-68.086508 -64.29766,-69.84264 -64.29766,-69.84264 -63.103109,-69.84264 -61.908558,-69.84264 -60.714007,-69.84264 -59.519456,-69.84264 -58.324905,-69.84264 -57.130354,-69.84264 -55.935803,-69.84264 -54.741252,-69.84264 -53.546701,-69.84264 -52.35215))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001571", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0602A"}, {"dataset_uid": "001602", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0502"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this \"demonstration cruise\" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the \"Greenhouse-Icehouse\" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program\u0027s technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the \"no man\u0027s land\" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program\u0027s vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.", "east": -52.28132, "geometry": "POINT(-61.06198 -58.324905)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ROCK CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.35215, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, John; Wellner, Julia", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.29766, "title": "Collaborative Research: SHALDRIL - A Demonstration Drilling Cruise to the James Ross Basin", "uid": "p0000571", "west": -69.84264}, {"awards": "9614028 Dymond, Jack", "bounds_geometry": "POLYGON((-179.9993 -63.09006,-143.99946 -63.09006,-107.99962 -63.09006,-71.99978 -63.09006,-35.99994 -63.09006,-0.000100000000003 -63.09006,35.99974 -63.09006,71.99958 -63.09006,107.99942 -63.09006,143.99926 -63.09006,179.9991 -63.09006,179.9991 -64.490422,179.9991 -65.890784,179.9991 -67.291146,179.9991 -68.691508,179.9991 -70.09187,179.9991 -71.492232,179.9991 -72.892594,179.9991 -74.292956,179.9991 -75.693318,179.9991 -77.09368,143.99926 -77.09368,107.99942 -77.09368,71.99958 -77.09368,35.99974 -77.09368,-0.000100000000003 -77.09368,-35.99994 -77.09368,-71.99978 -77.09368,-107.99962 -77.09368,-143.99946 -77.09368,-179.9993 -77.09368,-179.9993 -75.693318,-179.9993 -74.292956,-179.9993 -72.892594,-179.9993 -71.492232,-179.9993 -70.09187,-179.9993 -68.691508,-179.9993 -67.291146,-179.9993 -65.890784,-179.9993 -64.490422,-179.9993 -63.09006))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002161", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9605"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "96-14028 Dymond This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. This work is one of forty-four projects that are collaborating in the Southern Ocean Experiment, a three-year effort south of the Antarctic Polar Frontal Zone to track the flow of carbon through its organic and inorganic pathways from the air-ocean interface through the entire water column into the bottom sediment. The experiment will make use of the RVIB Nathaniel B. Palmer and the R/V Thompson. This component, a collaborative study by scientists from the Woods Hole Oceanographic Institution, Oregon State University, and the New Zealand Oceanographic Institution, concerns the export of particulate forms of carbon downward from the upper ocean. The observations will be obtained from an array of time- series sediment traps, and will be analyzed to quantify export fluxes from the Subtropical Front to the Ross Sea, over an 18- months period beginning the early austral summer of 1996. The measurement program will two annual phytoplankton blooms. The southern ocean provides a unique opportunity to investigate the processes controlling export flux in contrasting biogeochemical ocean zones demarcated by oceanic fronts. The temperature changes at the fronts coincide with gradients in nutrient concentrations and plankton ecology, resulting in a large latitudinal change in the ratio of calcium to silica taken up by the phytoplankton communities. This experiment will provide data on how the biological pump operates in the Southern Ocean and how it could potentially impact the level of atmospheric c arbon dioxide. The observed export fluxes of organic carbon, nitrogen, inorganic carbon, biogenic silica and alumina are central to the goals of the JGOFS program.", "east": 179.9991, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -63.09006, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Dymond, Jack", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.09368, "title": "Latitudinal Variations of Particle Fluxes in the Southern Ocean: A Bottom Tethered Sediment Trap Array Experiment", "uid": "p0000636", "west": -179.9993}, {"awards": "0338109 Brachfeld, Stefanie", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0603", "datasets": [{"dataset_uid": "002614", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0603", "url": "https://www.rvdata.us/search/cruise/NBP0603"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The Larsen Ice Shelf is the third largest ice shelf in Antarctica and has continued a pattern of catastrophic decay since the mid 1990\u0027s. The proposed marine geologic work at the Larsen Ice Shelf builds upon our previous NSF-OPP funding and intends to test the working hypothesis that the Larsen B Ice Shelf system has been a stable component of Antarctica\u0027s glacial system since it formed during rising sea levels 10,000 years BP. This conclusion, if supported by observations from our proposed work, is an important first step in establishing the uniqueness and consequences of rapid regional warming currently taking place across the Peninsula. Our previous work in the Larsen A and B embayments has allowed us to recognize the signature of past ice shelf fluctuations and their impact on the oceanographic and biologic environments. We have also overcome many of the limitations of standard radiocarbon dating in Antarctic marine sequences by using variations in the strength of the earth\u0027s magnetic field for correlation of sediment records and by using specific organic compounds (instead of bulk sediment) for radiocarbon dating. We intend to pursue these analytical advances and extend our sediment core stratigraphy to areas uncovered by the most recent collapse of the Larsen B Ice Shelf and areas immediately adjacent to the Larsen C Ice Shelf. In addition to the core recovery program, we intend to utilize our unique access to the ice shelf front to continue our observations of the snow/ice stratigraphy, oceanographic character, and ocean floor character. Sediment traps will also be deployed in order to measure the input of debris from glaciers that are now surging in response to the ice shelf collapse. This proposal is a multi-institutional, international (USAP, Italy, and Canada) effort that combines the established expertise in a variety of disciplines and integrates the research plan into the educational efforts of primarily undergraduate institutions but including some graduate education. This is a three-year project with field seasons planned with flexibility in order to accommodate schedules for the RVIB L.M. Gould. The Antarctic Peninsula is undergoing greater warming than almost anywhere on Earth, perhaps associated with human-induced greenhouse effects. Our proposed work contributes to understanding of these changes where they are occurring first and with greatest magnitude and impact upon the environment.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Brachfeld, Stefanie; Domack, Eugene Walter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Paleohistory of the Larsen Ice Shelf: Phase II", "uid": "p0000826", "west": null}, {"awards": "9317538 Nelson, David", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP9406", "datasets": [{"dataset_uid": "002252", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9406"}, {"dataset_uid": "002591", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP9406", "url": "https://www.rvdata.us/search/cruise/NBP9406"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. This component will test the closely related hypotheses that: (1) phytoplankton growth is controlled primarily by the relationship between solar irradiance and mixed-layer depth throughout the spring (2) diatom growth rates are much higher in spring than at any other time of year, in response to the more favorable irradiance/mixing relationships, and (3) persistence of diatom blooms in summer results from the diatoms\u0027 ability to outcompete other groups under the light-limited conditions that develop in turbid, high-biomass waters. These hypotheses will be tested by (1) obtaining the first reliable estimates of the Sverdrup \"critical depth\" in the Antarctic so that the changing relationship between the critical depth and the mixed- layer depth in spring can be defined, and (2) estimating diatom growth rates and the gross and net production attributable to diatoms throughout the spring. The results will provide information critical to an understanding of phytoplankton bloom dynamics in the Ross Sea.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Smith, Walker", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Bloom Dynamics and Food-Web Structure in the Ross Sea: The Irradiance/Mixing Regime and Diatom Growith in Spring", "uid": "p0000810", "west": null}, {"awards": "0636975 Sweeney, Colm", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG0909", "datasets": [{"dataset_uid": "002721", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0909", "url": "https://www.rvdata.us/search/cruise/LMG0909"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The proposed project will expand the suite of observations and lengthen the existing time series of underway surface dissolved carbon dioxide (pCO2) measurements transects across the Drake Passage on the R/VIB L.M. Gould. The additional observations include oxygen, nutrients and total CO2 (TCO2) concentrations, and the 13C to 12C ratio of TCO2. The continued and expanded time series will contribute towards two main scientific goals: the quantification of the spatial and temporal variability and the trends of surface carbon dioxide species in four major water mass regimes in the Drake Passage, and the understanding of the dominant processes and changes in those processes that contribute to the variability in surface pCO2 and the resulting air-sea flux of CO2 in the Drake Passage. The expanded program will also include the analysis of the 14C/12C of TCO2 and the specific study of the observations on one short wintertime cruise, with the objective of testing the hypothesis that the dissolved carbon dioxide in surface waters of the Drake Passage is determined by the degree of winter mixing. This is of special significance in light of two scenarios that may be affecting the ventilation of Southern Ocean deep water now and in the future: a decrease in water column stratification with the observations of higher zonal winds, or an increase in stratification due to higher precipitation and warming from climate change. If winter mixing determines the mean annual pCO2 in the Drake Passage, the increasing trend in atmospheric pCO2 should have little effect on sea surface pCO2.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Sweeney, Colm; Sweeney, Colm", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Surface pCO2 and the effects of Winter Time Overturning in the Drake Passage", "uid": "p0000872", "west": null}, {"awards": "9317587 Smith, Walker", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP9406", "datasets": [{"dataset_uid": "002252", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9406"}, {"dataset_uid": "002582", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP9406", "url": "https://www.rvdata.us/search/cruise/NBP9406"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. This component will conduct a set of process-oriented experiments designed to elucidate the controls of phytoplankton productivity, growth and accumulation as well as the mechanisms which control bacterial abundance and productivity in Antarctic waters. Specifically, the relative photosynthetic and nutrient (nitrate, ammonium) characteristics of diatom- vs. Phaeocystis- dominated assemblages will be examined to test if Phaeocystis simply grows faster under spring conditions in the Ross Sea. Phytoplankton and bacterial biomass, productivity and their interactions will be measured to elucidate the complex physical-chemical-biological interactions which occur. Substantial understanding of the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions will result from this research. Finally, because the Antarctic is the ocean\u0027s largest high-nutrient, low biomass system, and hence has the greatest potential for sequestering carbon dioxide, knowledge of the dynamics of the Ross Sea phytoplankton will also increase our understanding of the carbo n cycle of the Southern Ocean.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Bloom Dynamics and Food Web Structure in the Ross Sea: Primary Productivity, New Production and Bacterial Growth", "uid": "p0000802", "west": null}, {"awards": "0732995 Barbeau, David", "bounds_geometry": "POLYGON((-67.9988 -52.7596,-66.83756 -52.7596,-65.67632 -52.7596,-64.51508 -52.7596,-63.35384 -52.7596,-62.1926 -52.7596,-61.03136 -52.7596,-59.87012 -52.7596,-58.70888 -52.7596,-57.54764 -52.7596,-56.3864 -52.7596,-56.3864 -54.15258,-56.3864 -55.54556,-56.3864 -56.93854,-56.3864 -58.33152,-56.3864 -59.7245,-56.3864 -61.11748,-56.3864 -62.51046,-56.3864 -63.90344,-56.3864 -65.29642,-56.3864 -66.6894,-57.54764 -66.6894,-58.70888 -66.6894,-59.87012 -66.6894,-61.03136 -66.6894,-62.1926 -66.6894,-63.35384 -66.6894,-64.51508 -66.6894,-65.67632 -66.6894,-66.83756 -66.6894,-67.9988 -66.6894,-67.9988 -65.29642,-67.9988 -63.90344,-67.9988 -62.51046,-67.9988 -61.11748,-67.9988 -59.7245,-67.9988 -58.33152,-67.9988 -56.93854,-67.9988 -55.54556,-67.9988 -54.15258,-67.9988 -52.7596))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001520", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0717"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project studies the relationship between opening of the Drake Passage and formation of the Antarctic ice sheet. Its goal is to answer the question: What drove the transition from a greenhouse to icehouse world thirty-four million years ago? Was it changes in circulation of the Southern Ocean caused by the separation of Antarctica from South America or was it a global effect such as decreasing atmospheric CO2 content? This study constrains the events and timing through fieldwork in South America and Antarctica and new work on marine sediment cores previously collected by the Ocean Drilling Program. It also involves an extensive, multidisciplinary analytical program. Compositional analyses of sediments and their sources will be combined with (U-Th)/He, fission-track, and Ar-Ar thermochronometry to constrain uplift and motion of the continental crust bounding the Drake Passage. Radiogenic isotope studies of fossil fish teeth found in marine sediment cores will be used to trace penetration of Pacific seawater into the Atlantic. Oxygen isotope and trace metal measurements on foraminifera will provide additional information on the timing and magnitude of ice volume changes. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eThe broader impacts include graduate and undergraduate education; outreach to the general public through museum exhibits and presentations, and international collaboration with scientists from Argentina, Ukraine, UK and Germany.\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eThe project is supported under NSF\u0027s International Polar Year (IPY) research emphasis area on \"Understanding Environmental Change in Polar Regions\". This project is also a key component of the IPY Plates \u0026 Gates initiative (IPY Project #77), focused on determining the role of tectonic gateways in instigating polar environmental change.", "east": -56.3864, "geometry": "POINT(-62.1926 -59.7245)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.7596, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "MacPhee, Ross", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -66.6894, "title": "Collaborative Research: IPY: Testing the Polar Gateway Hypothesis: An Integrated Record of Drake Passage Opening \u0026 Antarctic Glaciation", "uid": "p0000120", "west": -67.9988}, {"awards": "9220009 Jacobs, Stanley", "bounds_geometry": "POLYGON((-179.99 -52.3518,-143.9914 -52.3518,-107.9928 -52.3518,-71.9942 -52.3518,-35.9956 -52.3518,0.00299999999999 -52.3518,36.0016 -52.3518,72.0002 -52.3518,107.9988 -52.3518,143.9974 -52.3518,179.996 -52.3518,179.996 -54.91842,179.996 -57.48504,179.996 -60.05166,179.996 -62.61828,179.996 -65.1849,179.996 -67.75152,179.996 -70.31814,179.996 -72.88476,179.996 -75.45138,179.996 -78.018,143.9974 -78.018,107.9988 -78.018,72.0002 -78.018,36.0016 -78.018,0.00300000000001 -78.018,-35.9956 -78.018,-71.9942 -78.018,-107.9928 -78.018,-143.9914 -78.018,-179.99 -78.018,-179.99 -75.45138,-179.99 -72.88476,-179.99 -70.31814,-179.99 -67.75152,-179.99 -65.1849,-179.99 -62.61828,-179.99 -60.05166,-179.99 -57.48504,-179.99 -54.91842,-179.99 -52.3518))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002257", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9402"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project will be the first systematic oceanographic study of the continental shelves of the Amundsen and Bellings-hausen Seas, and will include temperature and salinity profiling, water sampling for ocean chemistry, and continuous precision bathymetry. Upwelling warm deep water covers the Amundsen and Bellings-hausen shelves and delivers significant amounts of heat to the sea ice and fringing ice shelves. The regional precipitation is heavy, and has historically maintained a perennial ice cover. However, within the last few years satellite images have shown that the ice has been receding dramatically, with large areas of open water persisting through the winter in sectors that earlier had been ice-covered. These anomalous ice distributions are likely to have been accompanied by altered surface water properties, and possibly changes in the deep vertical circulation. There are indications that the conditions favoring a reduction in the sea ice may migrate westward toward the Ross Sea, and may have influenced a gradual warming over recent decades on the western side of the Antarctic Peninsula. The project will make use of the R/V Nathaniel B. Palmer in two cruises; one in the late austral summer 1993-1994, and a subse- quent cruise in September and October to observe late winter conditions.", "east": 179.996, "geometry": "POINT(0.00299999999999 -65.1849)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.3518, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jacobs, Stanley", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.018, "title": "Oceanography of the Amundsen and Bellingshausen Seas", "uid": "p0000648", "west": -179.99}, {"awards": "9117721 Jeffries, Martin", "bounds_geometry": "POLYGON((-110.149 -52.353,-104.86076 -52.353,-99.57252 -52.353,-94.28428 -52.353,-88.99604 -52.353,-83.7078 -52.353,-78.41956 -52.353,-73.13132 -52.353,-67.84308 -52.353,-62.55484 -52.353,-57.2666 -52.353,-57.2666 -54.17539,-57.2666 -55.99778,-57.2666 -57.82017,-57.2666 -59.64256,-57.2666 -61.46495,-57.2666 -63.28734,-57.2666 -65.10973,-57.2666 -66.93212,-57.2666 -68.75451,-57.2666 -70.5769,-62.55484 -70.5769,-67.84308 -70.5769,-73.13132 -70.5769,-78.41956 -70.5769,-83.7078 -70.5769,-88.99604 -70.5769,-94.28428 -70.5769,-99.57252 -70.5769,-104.86076 -70.5769,-110.149 -70.5769,-110.149 -68.75451,-110.149 -66.93212,-110.149 -65.10973,-110.149 -63.28734,-110.149 -61.46495,-110.149 -59.64256,-110.149 -57.82017,-110.149 -55.99778,-110.149 -54.17539,-110.149 -52.353))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002283", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9305"}, {"dataset_uid": "002253", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9405"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is an examination of the physical and structural properties of the antarctic ice pack in the Amundsen, Bellingshausen, and Ross Seas, with the goal of defining the geographical variability of various ice types, the deformation processes that are active in the antarctic ice pack, and the large-scale thermodynamics and heat exchange processes of the ice- covered Southern Ocean. An additional goal is to relate specific characteristics of antarctic sea ice to its synthetic aperture radar (SAR) signature as observed from satellites. Physical properties include the salinity, temperature, and brine volumes, while structural properties include the fraction of frazil, platelet, and congelation ice of the seasonal antarctic pack ice. Differences in ice types are the result of differences in the environment in which the ice forms: frazil ice is formed in supercooled sea water, normally through wind or wave-induced turbulence, while platelet and congelation ice is formed under quiescent conditions. The fraction of frazil ice (which has been observed to be generally in excess of 50% in Weddell Sea ice floes) is an important variable in the energy budget of the upper ocean, and contributes significantly to the stabilization of the surface layers. The integration of sea ice field observations and synthetic aperture radar data analysis and modeling studies will contribute to a better understanding of sea ice parameters and their geophysical controls, and will be useful in defining the kind of air-ice-ocean interactions that can be studied using SAR data, as well as having broader relevance and application to atmospheric, biological, and oceanographic investigations of the Southern Ocean.", "east": -57.2666, "geometry": "POINT(-83.7078 -61.46495)", "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.353, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jeffries, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -70.5769, "title": "Sea Ice Physical-Structrual Characteristics: Development and SAR Signature in the Pacific Sector of the Southern Ocean", "uid": "p0000647", "west": -110.149}, {"awards": "9725024 Jacobs, Stanley", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0001; Expedition data of NBP0008; Summer Oceanographic Measurements near the Mertz Polynya NBP0008", "datasets": [{"dataset_uid": "002598", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0001", "url": "https://www.rvdata.us/search/cruise/NBP0001"}, {"dataset_uid": "601161", "doi": "10.15784/601161 ", "keywords": "Antarctica; CTD; CTD Data; Mertz Polynya; NBP0008; Oceans; Oxygen; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Southern Ocean; Temperature", "people": "Jacobs, Stanley; Smethie, William M; Mortlock, R. A.; Mele, Phil", "repository": "USAP-DC", "science_program": null, "title": "Summer Oceanographic Measurements near the Mertz Polynya NBP0008", "url": "https://www.usap-dc.org/view/dataset/601161"}, {"dataset_uid": "002599", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0008", "url": "https://www.rvdata.us/search/cruise/NBP0008"}, {"dataset_uid": "001885", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0008"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project will study the dynamics of Circumpolar Deep Water intruding on the continental shelf of the West Antarctic coast, and the effect of this intrusion on the production of cold, dense bottom water, and melting at the base of floating glaciers and ice tongues. It will concentrate on the Amundsen Sea shelf, specifically in the region of the Pine Island Glacier, the Thwaites Glacier, and the Getz Ice Shelf. Circumpolar Deep Water (CDW) is a relatively warm water mass (warmer than +1.0 deg Celsius) which is normally confined to the outer edge of the continental shelf by an oceanic front separating this water mass from colder and saltier shelf waters. In the Amundsen Sea however, the deeper parts of the continental shelf are filled with nearly undiluted CDW, which is mixed upward, delivering significant amounts of heat to the base of the floating glacier tongues and the ice shelf. The melt rate beneath the Pine Island Glacier averages ten meters of ice per year with local annual rates reaching twenty meters. By comparison, melt rates beneath the Ross Ice Shelf are typically twenty to forty centimeters of ice per year. In addition, both the Pine Island and the Thwaites Glacier are extremely fast-moving, and have a significant effect on the regional ice mass balance of West Antarctica. This project therefore has an important connection to antarctic glaciology, particularly in assessing the combined effect of global change on the antarctic environment. The particular objectives of the project are (1) to delineate the frontal structure on the continental shelf sufficiently to define quantitatively the major routes of CDW inflow, meltwater outflow, and the westward evolution of CDW influence; (2) to use the obtained data set to validate a three-dimensional model of sub-ice ocean circulation that is currently under construction, and (3) to refine the estiamtes of in situ melting on the mass balance of the antarctic ice sheet. The observational program will be carried out from the research vessel Nathaniel B. Palmer in February and March, 1999. ***", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jacobs, Stanley", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Circumpolar Deep Water and the West Antarctic Ice Sheet", "uid": "p0000815", "west": null}, {"awards": "0338097 DiTullio, Giacomo; 0338350 Dunbar, Robert; 0741411 Hutchins, David; 0338157 Smith, Walker; 0127037 Neale, Patrick", "bounds_geometry": "POLYGON((173.31833 -46.5719,173.757539 -46.5719,174.196748 -46.5719,174.635957 -46.5719,175.075166 -46.5719,175.514375 -46.5719,175.953584 -46.5719,176.392793 -46.5719,176.832002 -46.5719,177.271211 -46.5719,177.71042 -46.5719,177.71042 -48.759516,177.71042 -50.947132,177.71042 -53.134748,177.71042 -55.322364,177.71042 -57.50998,177.71042 -59.697596,177.71042 -61.885212,177.71042 -64.072828,177.71042 -66.260444,177.71042 -68.44806,177.271211 -68.44806,176.832002 -68.44806,176.392793 -68.44806,175.953584 -68.44806,175.514375 -68.44806,175.075166 -68.44806,174.635957 -68.44806,174.196748 -68.44806,173.757539 -68.44806,173.31833 -68.44806,173.31833 -66.260444,173.31833 -64.072828,173.31833 -61.885212,173.31833 -59.697596,173.31833 -57.50998,173.31833 -55.322364,173.31833 -53.134748,173.31833 -50.947132,173.31833 -48.759516,173.31833 -46.5719))", "dataset_titles": "Expedition Data; Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea; Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601", "datasets": [{"dataset_uid": "001687", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0305"}, {"dataset_uid": "001545", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0608"}, {"dataset_uid": "001584", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0508"}, {"dataset_uid": "601340", "doi": null, "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Fluid Chemistry Data; Geochemistry; NBP0601; Niskin Bottle; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Southern Ocean; Water Measurements", "people": "Smith, Walker; DiTullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601", "url": "https://www.usap-dc.org/view/dataset/601340"}, {"dataset_uid": "001580", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0601"}, {"dataset_uid": "600036", "doi": "10.15784/600036", "keywords": "Biota; Chemistry:fluid; Chemistry:Fluid; Diatom; Oceans; Phytoplankton; Ross Sea; Southern Ocean", "people": "DiTullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600036"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. \u003cbr/\u003eThis project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images.", "east": 177.71042, "geometry": "POINT(175.514375 -57.50998)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FRRF; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FRRF", "is_usap_dc": true, "keywords": "B-15J; OCEAN PLATFORMS; FIELD SURVEYS; R/V NBP", "locations": "B-15J", "north": -46.5719, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ditullio, Giacomo; Smith, Walker; Dryer, Jennifer; Neale, Patrick", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; WATER-BASED PLATFORMS \u003e FIXED PLATFORMS \u003e SURFACE \u003e OCEAN PLATFORMS; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -68.44806, "title": "Collaborative Research: Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea", "uid": "p0000540", "west": 173.31833}, {"awards": "0837988 Steig, Eric", "bounds_geometry": "POLYGON((-180 -65,-144 -65,-108 -65,-72 -65,-36 -65,0 -65,36 -65,72 -65,108 -65,144 -65,180 -65,180 -67.5,180 -70,180 -72.5,180 -75,180 -77.5,180 -80,180 -82.5,180 -85,180 -87.5,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.5,-180 -85,-180 -82.5,-180 -80,-180 -77.5,-180 -75,-180 -72.5,-180 -70,-180 -67.5,-180 -65))", "dataset_titles": "West Antarctica Ice Core and Climate Model Data", "datasets": [{"dataset_uid": "609536", "doi": "10.7265/N5QJ7F8B", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; WAIS Divide", "people": "Steig, Eric J.", "repository": "USAP-DC", "science_program": null, "title": "West Antarctica Ice Core and Climate Model Data", "url": "https://www.usap-dc.org/view/dataset/609536"}], "date_created": "Fri, 30 Apr 2010 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). \u003cbr/\u003e\u003cbr/\u003eThis award supports a project to reconstruct the past physical and chemical climate of Antarctica, with an emphasis on the region surrounding the Ross Sea Embayment, using \u003e60 ice cores collected in this region by US ITASE and by Australian, Brazilian, Chilean, and New Zealand ITASE teams. The ice core records are annually resolved and exceptionally well dated, and will provide, through the analyses of stable isotopes, major soluble ions and for some trace elements, instrumentally calibrated proxies for past temperature, precipitation, atmospheric circulation, chemistry of the atmosphere, sea ice extent, and volcanic activity. These records will be used to understand the role of solar, volcanic, and human forcing on Antarctic climate and to investigate the character of recent abrupt climate change over Antarctica in the context of broader Southern Hemisphere and global climate variability. The intellectual merit of the project is that ITASE has resulted in an array of ice core records, increasing the spatial resolution of observations of recent Antarctic climate variability by more than an order of magnitude and provides the basis for assessment of past and current change and establishes a framework for monitoring of future climate change in the Southern Hemisphere. This comes at a critical time as global record warming and other impacts are noted in the Southern Ocean, the Antarctic Peninsula, and on the Antarctic ice sheet. The broader impacts of the project are that Post-doctoral and graduate students involved in the project will benefit from exposure to observational and modeling approaches to climate change research and working meetings to be held at the two collaborating institutions plus other prominent climate change institutions. The results are of prime interest to the public and the media Websites hosted by the two collaborating institutions contain climate change position papers, scientific exchanges concerning current climate change issues, and scientific contribution series.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Deuterium Isotopes; Deuterium Excess; Not provided; GROUND-BASED OBSERVATIONS; Wais Divide-project", "locations": null, "north": -65.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Antarctic Climate Reconstruction Utilizing the US ITASE Ice Core Array (2009- 2012)", "uid": "p0000180", "west": -180.0}, {"awards": "0538639 Waddington, Edwin", "bounds_geometry": "POLYGON((-112.1 -79.4,-112.09 -79.4,-112.08 -79.4,-112.07 -79.4,-112.06 -79.4,-112.05 -79.4,-112.04 -79.4,-112.03 -79.4,-112.02 -79.4,-112.01 -79.4,-112 -79.4,-112 -79.41,-112 -79.42,-112 -79.43,-112 -79.44,-112 -79.45,-112 -79.46,-112 -79.47,-112 -79.48,-112 -79.49,-112 -79.5,-112.01 -79.5,-112.02 -79.5,-112.03 -79.5,-112.04 -79.5,-112.05 -79.5,-112.06 -79.5,-112.07 -79.5,-112.08 -79.5,-112.09 -79.5,-112.1 -79.5,-112.1 -79.49,-112.1 -79.48,-112.1 -79.47,-112.1 -79.46,-112.1 -79.45,-112.1 -79.44,-112.1 -79.43,-112.1 -79.42,-112.1 -79.41,-112.1 -79.4))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 01 Apr 2010 00:00:00 GMT", "description": "0538639\u003cbr/\u003eWaddington\u003cbr/\u003eThis award supports a project to study the patterns of accumulation variation and microstructural properties near the WAIS Divide ice core site in a 2.5 km array of 20 m boreholes. Borehole Optical Stratigraphy (BOS) is a novel optical measurement system that detects annual-scale layers in firn that result from changes in firn microstructure, giving annual-scale records of how accumulation varied spatially over the last 40-50 years. Data from borehole optical stratigraphy can eventually be calibrated against other data on the microstructural parameters of firn to calibrate BOS\u0027s sensitivity to density, pore-volume, and pore-shape variations, and to show by proxy how these parameters vary in space across the survey area. Statistical analysis of layer-thickness and layer-brightness data will enable prediction of: 1) interannual accumulation variability, 2) variability in layer-thickness at decadal scales due to changing spatial patterns in accumulation and 3) variability in microstructure-driven metamorphism due to changing spatial patterns of microstructure. With these statistics in hand, a scientist measuring climatic shifts found in the WAIS Divide ice core will be able to determine the fraction by which signals they measure exceed the signal due to background accumulation variations. As an added benefit, while still in the field, we will determine a preliminary depth-age scale for the firn by optical layer-counting, to the depth of the deepest air-filled firn hole available. This will be a valuable result for core-drilling operations and for preliminary data-analysis on the core. In terms of broader impacts, this project will advance education by training a post-doctoral student in field techniques. The P.I. and the post-doctoral researcher will participate in an undergraduate seminar called \"What is Scientific Research?\", incorporating progress and results from this project. They will also communicate about their progress and field experience with a middle-school science and math class.", "east": -112.0, "geometry": "POINT(-112.05 -79.45)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e OPTICAL DUST LOGGERS", "is_usap_dc": false, "keywords": "Spatial Variability; FIELD INVESTIGATION; Not provided; LABORATORY; Stratigraphy; Borehole Optical Stratigraphy; Optical Layer-Counting; Microstructure; Firn; Depth-Age-Model; Optical; WAIS Divide; FIELD SURVEYS; Accumulation", "locations": "WAIS Divide", "north": -79.4, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fudge, T. J.; Waddington, Edwin D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -79.5, "title": "Spatial Variability in Firn Properties from Borehole Optical Stratigraphy at the Inland WAIS Core Site", "uid": "p0000237", "west": -112.1}, {"awards": "0440666 Waddington, Edwin", "bounds_geometry": null, "dataset_titles": "Histories of Accumulation, Thickness, and WAIS Divide Location, Antarctica", "datasets": [{"dataset_uid": "609473", "doi": "10.7265/N5QR4V2J", "keywords": "Antarctica; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; WAIS Divide; WAIS Divide Ice Core", "people": "Waddington, Edwin D.; Koutnik, Michelle", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Histories of Accumulation, Thickness, and WAIS Divide Location, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609473"}], "date_created": "Thu, 04 Mar 2010 00:00:00 GMT", "description": "This award supports development of a new modeling approach that will extract information about past snow accumulation rate in both space and time in the vicinity of the future ice core near the Ross-Amundsen divide of the West Antarctic Ice Sheet (WAIS). Internal layers, detected by ice-penetrating radar, are isochrones, or former ice-sheet surfaces that have been buried by subsequent snowfall, and distorted by ice flow. Extensive ice-penetrating radar data are available over the inland portion of the WAIS. Layers have been dated back to 17,000 years before present. The radar data add the spatial dimension to the temporally resolved accumulation record from ice cores. Accumulation rates are traditionally derived from the depths of young, shallow layers, corrected for strain using a local 1-D ice-flow model. Older, deeper layers have been more affected by flow over large horizontal distances. However, it is these deeper layers that contain information on longer-term climate patterns. This project will use geophysical inverse theory and a 2.5D flow-band ice-flow forward model comprising ice-surface and layer-evolution modules, to extract robust transient accumulation patterns by assimilating multiple deeper, more-deformed layers that have previously been intractable. Histories of divide migration, geothermal flux, and surface evolution will also be produced. The grant will support the PhD research of a female graduate student who is a mentor to female socio-economically disadvantaged high-school students interested in science, through the University of Washington Women\u0027s Center. It will also provide a research\u003cbr/\u003eexperience for an undergraduate student, and contribute to a freshman seminar on Scientific Research.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS", "is_usap_dc": true, "keywords": "Ross-Amundsen Divide; FIELD SURVEYS; Internal Layers; Ice Flow Model; West Antarctic Ice Sheet; Accumulation; Glacier; Ice Penetrating Radar; Model; MODELS; Snow Accumulation; GPS; Antarctica; Isochron; Not provided; Snowfall; Radar", "locations": "West Antarctic Ice Sheet; Antarctica; Ross-Amundsen Divide", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Koutnik, Michelle; Waddington, Edwin D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e MODELS \u003e MODELS; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": null, "title": "Histories of accumulation, thickness and WAIS Divide location from radar layers using a new inverse approach", "uid": "p0000018", "west": null}, {"awards": "0741510 Yuan, Xiaojun", "bounds_geometry": "POLYGON((-180 -69,-172 -69,-164 -69,-156 -69,-148 -69,-140 -69,-132 -69,-124 -69,-116 -69,-108 -69,-100 -69,-100 -70,-100 -71,-100 -72,-100 -73,-100 -74,-100 -75,-100 -76,-100 -77,-100 -78,-100 -79,-108 -79,-116 -79,-124 -79,-132 -79,-140 -79,-148 -79,-156 -79,-164 -79,-172 -79,180 -79,178.5 -79,177 -79,175.5 -79,174 -79,172.5 -79,171 -79,169.5 -79,168 -79,166.5 -79,165 -79,165 -78,165 -77,165 -76,165 -75,165 -74,165 -73,165 -72,165 -71,165 -70,165 -69,166.5 -69,168 -69,169.5 -69,171 -69,172.5 -69,174 -69,175.5 -69,177 -69,178.5 -69,-180 -69))", "dataset_titles": "Temperature and salinity measurements collected using XBT, XCTD from the Oden and other platforms in the Southern Oceans from 2003-2008 (NODC Accession 0053045)", "datasets": [{"dataset_uid": "000214", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Temperature and salinity measurements collected using XBT, XCTD from the Oden and other platforms in the Southern Oceans from 2003-2008 (NODC Accession 0053045)", "url": "https://data.nodc.noaa.gov/cgi-bin/iso?id=gov.noaa.nodc:0053045"}], "date_created": "Sat, 20 Feb 2010 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe project goal is to investigate the ocean-atmosphere-ice (OAI) interactions in the Amundsen and Ross Seas during the austral summer of 2007-08 using hydrographic measurements (CTD and XBT) in conjunction with (1) ship-based observations and satellite-derived estimates of sea ice concentration, and (2) ship-based observations and re-analyses of meteorological variables. The major scientific objectives are as follows: (1) to examine upper ocean characteristics along three transects in the Amundsen Sea and two transects in the Ross Sea within the context of ice-atmosphere variability over the preceding winter-spring season and as compared to other years where data are available; (2) to determine if there is additional evidence of increased upwelling of warm Circumpolar Deep Water onto the shelf in the Amundsen Sea and/or increased freshening in the Ross Sea as has been inferred by previous, but limited, ocean surveys in these regions; and (3) to examine the spatial variability in ocean thermal structure along the ship\u0027s track (outside the transects) to provide greater regional context and to compare with ocean XBT data collected during Oden 2006-07. A repeated temperature survey between the Amundsen and Ross Sea is particularly invaluable, given that this sector is the regional center of the high latitude OAI response to ENSO, thus providing opportunity for examining and linking regional oceanic temporal variability to global climate variability. The research will improve our understanding of the high latitude OAI response to climate change, and provide the physical context for the observed biology and geochemistry (investigated by our colleagues. Our results will be made widely available through research publications and internet-available databases, and through the strong public outreach efforts of Lamont-Doherty Earth Observatory. The outreach efforts will help increase awareness and understanding of anthropogenic climate change, melting ice, and ecosystem alteration in the highly sensitive Antarctic.", "east": -100.0, "geometry": "POINT(-147.5 -74)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -69.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Yuan, Xiaojun; Stammerjohn, Sharon", "platforms": "Not provided", "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -79.0, "title": "SGER: Science-of-Opportunity Aboard Icebreaker Oden: Ocean-Atmosphere-Ice Interactions and Changes", "uid": "p0000562", "west": 165.0}, {"awards": "0551969 Moran, Amy", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 12 Jan 2010 00:00:00 GMT", "description": "This project seeks to understand the evolutionary physiology of reproductive strategies in Southern Ocean marine invertebrates. The fauna of the Southern Ocean has evolved under stable, cold temperatures for approximately 14 million years. These conditions have led to the evolution of unusual physiological and biochemical characteristics, many of which may reflect adaptations to relatively low oxygen availability and high larval oxygen demands. The goal of the proposed projects is to understand latitudinal variation in the function of invertebrate egg masses in relation to oxygen availability and temperature. This relationship is critical to larval survival in the low-temperature, high-oxygen conditions found at high latitudes. In particular, the investigators will: (1) use first principles to model the diffusion of oxygen into egg and embryo masses of Antarctic organisms at environmentally relevant temperatures; (2) test model assumptions by measuring the temperature-dependence of embryonic metabolism and oxygen diffusivity through natural and artificial gels; (3) test model predictions by using oxygen microelectrodes to measure oxygen gradients in both artificial and natural egg masses, and by measuring developmental rates of embryos at different positions in masses; and (4) compare the structure and function of egg masses from the Southern Ocean to those from temperate waters. These components of the study constitute an integrated examination of the evolutionary physiology of egg mass structure and function. Studies of masses endemic to polar conditions will increase the understanding of egg mass evolution across equator-to-pole gradients in temperature and across gradients in oxygen partial pressure. The proposal will support graduate students and will involve several undergraduates in research. The PIs will also design and implement units on polar biology for undergraduate classes at their respective institutions. These educational units will focus on the PIs\u0027 photographs, video footage, experiments, and data from this project. The PIs will use web-linked video and instructional technologies to design and co-teach a new class on polar ecological physiology, will work with local grade school institutions to involve high school students in research, and will develop high school course modules about polar biology.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Moran, Amy", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Effects of Oxygen and Temperature on Egg Mass Function of Southern Ocean Marine Minvertebrates", "uid": "p0000716", "west": null}, {"awards": "0538594 Ponganis, Paul", "bounds_geometry": "POLYGON((165.983 -77.683,166.0164 -77.683,166.0498 -77.683,166.0832 -77.683,166.1166 -77.683,166.15 -77.683,166.1834 -77.683,166.2168 -77.683,166.2502 -77.683,166.2836 -77.683,166.317 -77.683,166.317 -77.6897,166.317 -77.6964,166.317 -77.7031,166.317 -77.7098,166.317 -77.7165,166.317 -77.7232,166.317 -77.7299,166.317 -77.7366,166.317 -77.7433,166.317 -77.75,166.2836 -77.75,166.2502 -77.75,166.2168 -77.75,166.1834 -77.75,166.15 -77.75,166.1166 -77.75,166.0832 -77.75,166.0498 -77.75,166.0164 -77.75,165.983 -77.75,165.983 -77.7433,165.983 -77.7366,165.983 -77.7299,165.983 -77.7232,165.983 -77.7165,165.983 -77.7098,165.983 -77.7031,165.983 -77.6964,165.983 -77.6897,165.983 -77.683))", "dataset_titles": "The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins", "datasets": [{"dataset_uid": "600057", "doi": "10.15784/600057", "keywords": "Antarctica; Biota; Oceans; Penguin; Southern Ocean", "people": "Ponganis, Paul", "repository": "USAP-DC", "science_program": null, "title": "The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins", "url": "https://www.usap-dc.org/view/dataset/600057"}], "date_created": "Sun, 20 Dec 2009 00:00:00 GMT", "description": "The research will examine blood and muscle oxygen store depletion in relation to the documented aerobic dive limit (ADL, onset of post-dive blood lactate accumulation) in diving of emperor penguins. The intellectual merits of this proposal involve its evaluation of the physiological basis of the ADL concept. The ADL is probably the most commonly-used, but rarely measured, factor to interpret and model the behavior and foraging ecology of diving animals. Based on prior studies, and on recent investigations of respiratory and blood oxygen depletion during dives of emperor penguins, it is hypothesized that the ADL is a result of the depletion of myoglobin (Mb)-bound oxygen and increased glycolysis in the primary locomotory muscles. This project will accurately define the physiological mechanisms underlying the ADL through 1) evaluation of the rate and magnitude of muscle oxygen depletion during dives in relation to the previously measured ADL, 2) characterization of the hemoglobin-oxygen dissociation curve in blood of emperor penguins and comparison of that curve to those of other diving and non-diving species, 3) application of the emperor hemoglogin-oxygen dissociation curve to previously collected oxygen and hemoglobin data in order to estimate the rate and magnitude of blood oxygen depletion during dives, and 4) measurement of muscle phosphoocreatine and glycogen concentrations in order to estimate their potential contributions to muscle energy metabolism during diving. The project also continues the census and monitoring of the emperor colonies in the Ross Sea, which is especially important in light of both fisheries activity and the movement of iceberg B15-A. Broader impacts of the project include: 1) technological development of microprocessor-based, \"backpack\" near-infrared spectrophotometer, which will be applicable not only to other species, but also to other fields (i.e., exercise physiology), 2) collaboration with the Department of Anesthesia at the U.S. Naval Hospital in San Diego in the training of anesthesia residents in research techniques, 3) the training and thesis research of two graduate students in these techniques and in Antarctic field research, and 4) a better understanding of the ADL concept and its use in the fields of diving behavior and physiology. In addition the annual census of emperor penguin colonies in the Ross Sea, in conjunction with the continued evaluation of previously developed remote cameras to monitor colony status, will form the basis of a new educational web site, and allow development of an educational outreach program to school children through SeaWorld of San Diego.", "east": 166.317, "geometry": "POINT(166.15 -77.7165)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.683, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ponganis, Paul", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.75, "title": "The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins", "uid": "p0000535", "west": 165.983}, {"awards": "0230285 Wilson, Terry", "bounds_geometry": "POLYGON((152.833 -75.317,154.4897 -75.317,156.1464 -75.317,157.8031 -75.317,159.4598 -75.317,161.1165 -75.317,162.7732 -75.317,164.4299 -75.317,166.0866 -75.317,167.7433 -75.317,169.4 -75.317,169.4 -75.9186,169.4 -76.5202,169.4 -77.1218,169.4 -77.7234,169.4 -78.325,169.4 -78.9266,169.4 -79.5282,169.4 -80.1298,169.4 -80.7314,169.4 -81.333,167.7433 -81.333,166.0866 -81.333,164.4299 -81.333,162.7732 -81.333,161.1165 -81.333,159.4598 -81.333,157.8031 -81.333,156.1464 -81.333,154.4897 -81.333,152.833 -81.333,152.833 -80.7314,152.833 -80.1298,152.833 -79.5282,152.833 -78.9266,152.833 -78.325,152.833 -77.7234,152.833 -77.1218,152.833 -76.5202,152.833 -75.9186,152.833 -75.317))", "dataset_titles": null, "datasets": null, "date_created": "Sat, 12 Dec 2009 00:00:00 GMT", "description": "OPP-0230285/OPP-0230356\u003cbr/\u003ePIs: Wilson, Terry J./Hothem, Larry D.\u003cbr/\u003e\u003cbr/\u003eThis award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to conduct GPS measurements of bedrock crustal motions in an extended Transantarctic Mountains Deformation network (TAMDEF) to document neotectonic displacements due to tectonic deformation within the West Antarctic rift and/or to mass change of the Antarctic ice sheets. Horizontal displacements related to active neotectonic rifting, strike-slip translations, and volcanism will be tightly constrained by monitoring the combined TAMDEF and Italian VLNDEF networks of bedrock GPS stations along the Transantarctic Mountains and on offshore islands in the Ross Sea. Glacio-isostatic adjustments due to deglaciation since the Last Glacial Maximum and to modern mass change of the ice sheets will be modeled from GPS-derived crustal motions together with new information from other programs on the configurations, thicknesses, deglaciation history and modern mass balance of the ice sheets. Tectonic and rheological information from ongoing structural and seismic investigations in the Victoria Land region will also be integrated in the modeling. The integrative and iterative modeling will yield a holistic interpretation of neotectonics and ice sheet history that will help us to discriminate tectonic crustal displacements from viscoelastic/elastic glacio-isostatic motions. These results will provide key information to interpret broad, continental-scale crustal motion patterns detected by sparse, regionally distributed GPS continuous trackers and by spaceborne instruments. This study will contribute to international programs focused on Antarctic neotectonic and global change issues.\u003cbr/\u003e\u003cbr/\u003eStrategies to meet these science objectives include repeat surveys of key sites in the existing TAMDEF network, extension of the array of TAMDEF sites southward about 250 km along the Transantarctic Mountains, linked measurements with the VLNDEF network, and integration of quasi-continuous trackers within the campaign network. By extending the array of bedrock sites southward, these measurements will cross gradients in predicted vertical motion due to viscoelastic rebound. The southward extension will also allow determination of the southern limit of the active Terror Rift and will provide a better baseline for constraints on any ongoing tectonic displacements across the West Antarctic rift system as a whole that might be possible using GPS data collected by the West Antarctic GPS Network. This project will also investigate unique aspects of GPS geodesy in Antarctica to determine how the error spectrum compares to mid-latitude regions and to identify the optimum measurement and data processing schemes for Antarctic conditions. The geodetic research will improve position accuracies within our network and will also yield general recommendations for deformation monitoring networks in polar regions.\u003cbr/\u003e\u003cbr/\u003eAn education and outreach program is planned and will be targeted at non-science-major undergraduate students taking Earth System Science at Ohio State University. The objective will be to illuminate the research process for nonscientists. This effort will educate students on the process of science and inform them about Antarctica and how it relates to global science issues.", "east": 169.4, "geometry": "POINT(161.1165 -78.325)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "GPS", "locations": null, "north": -75.317, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Wilson, Terry", "platforms": "SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repositories": null, "science_programs": null, "south": -81.333, "title": "Collaborative Research: Transantarctic Mountains Deformation Network: GPS Measurements of Neotectonic Motion in the Antarctic Interior", "uid": "p0000574", "west": 152.833}, {"awards": "0741380 Smith, Walker", "bounds_geometry": "POLYGON((100 -65,106 -65,112 -65,118 -65,124 -65,130 -65,136 -65,142 -65,148 -65,154 -65,160 -65,160 -66.5,160 -68,160 -69.5,160 -71,160 -72.5,160 -74,160 -75.5,160 -77,160 -78.5,160 -80,154 -80,148 -80,142 -80,136 -80,130 -80,124 -80,118 -80,112 -80,106 -80,100 -80,100 -78.5,100 -77,100 -75.5,100 -74,100 -72.5,100 -71,100 -69.5,100 -68,100 -66.5,100 -65))", "dataset_titles": "Small Grants for Exploratory Research - Oceanographic Research in the Amundsen and Ross Seas", "datasets": [{"dataset_uid": "600085", "doi": "10.15784/600085", "keywords": "Amundsen Sea; Chemistry:fluid; Chemistry:Fluid; CTD Data; Geochemistry; Oceans; Oden; OSO2007; Sea Surface; Southern Ocean", "people": "Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Small Grants for Exploratory Research - Oceanographic Research in the Amundsen and Ross Seas", "url": "https://www.usap-dc.org/view/dataset/600085"}], "date_created": "Mon, 22 Jun 2009 00:00:00 GMT", "description": "The research will examine the relative importance of the physical and chemical controls on phytoplankton dynamics and carbon flux in continental margin regions of the Southern Ocean, and elucidate mechanisms by which plankton populations and carbon export might be altered by climate change. We specifically will address (1) how the phytoplankton on the continental margins of the southern Ocean respond to spatial and temporal changes in temperature, light, iron supply, and carbon dioxide levels, (2) how these factors initiate changes in phytoplankton assemblage structure, and (3) how carbon export and the efficiency of the biological pump are impacted by the biomass and composition of the phytoplankton. Two regions of study (the Amundsen and Ross Seas) will be investigated, one well studied (Ross Sea) and one poorly described (Amundsen Sea). It is hypothesized that each region will have markedly different physical forcing, giving rise to distinct chemical conditions and therefore biological responses. As such, the comparison of the two may give us insights into the mechanisms of how Antarctic continental margins will respond under changing environmental conditions. Broader impacts include participation by an international graduate student from Brazil, outreach via seminars to the general public, collaboration with the teachers-in-residence on the cruise, development of a cruise web site and interactive email exchanges with local middle school students while at sea", "east": 160.0, "geometry": "POINT(130 -72.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -65.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Small Grants for Exploratory Research - Oceanographic Research in the Amundsen and Ross Seas:", "uid": "p0000217", "west": 100.0}, {"awards": "0636269 Harpp, Karen", "bounds_geometry": "POLYGON((161.55 -77.50314,161.5883 -77.50314,161.6266 -77.50314,161.66490000000002 -77.50314,161.7032 -77.50314,161.7415 -77.50314,161.7798 -77.50314,161.8181 -77.50314,161.8564 -77.50314,161.8947 -77.50314,161.933 -77.50314,161.933 -77.507124,161.933 -77.51110800000001,161.933 -77.515092,161.933 -77.519076,161.933 -77.52306,161.933 -77.527044,161.933 -77.531028,161.933 -77.535012,161.933 -77.538996,161.933 -77.54298,161.8947 -77.54298,161.8564 -77.54298,161.8181 -77.54298,161.7798 -77.54298,161.7415 -77.54298,161.7032 -77.54298,161.66490000000002 -77.54298,161.6266 -77.54298,161.5883 -77.54298,161.55 -77.54298,161.55 -77.538996,161.55 -77.535012,161.55 -77.531028,161.55 -77.527044,161.55 -77.52306,161.55 -77.519076,161.55 -77.515092,161.55 -77.51110800000001,161.55 -77.507124,161.55 -77.50314))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 03 Jun 2009 00:00:00 GMT", "description": "This project is a field and laboratory based investigation of the Vanda dike swarm in the Dry Valleys of Antarctica. These dikes crosscut Cambro-Ordovician granitoid plutons produced during the Ross Orogeny, and mark the transition between the cessation of subduction and the onset of extensional magmatism. Many dying convergent plate margins convert to extensional magmatism, and the Dry Valleys provide a magnificent opportunity to examine the shallow roots of a plate that experienced this transition. Because of their exceptional exposure, bimodal felsic and mafic compositions, and complex field relations, the Vanda dikes have the potential to reveal insights into this important phase of Antarctic tectonic history. \u003cbr/\u003eThe broader impacts include collaboration between a primarily undergraduate and two research institutions, and support for undergraduate participation in an exciting, field-based research project.", "east": 161.933, "geometry": "POINT(161.7415 -77.52306)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.50314, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Harpp, Karen", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.54298, "title": "Collaborative Research, RUI: The Transition from Subduction to Extensional Magmatism in the Dry Valleys of Antarctica", "uid": "p0000546", "west": 161.55}, {"awards": "0439759 Ballard, Grant", "bounds_geometry": "POLYGON((-180 -60,-177.5 -60,-175 -60,-172.5 -60,-170 -60,-167.5 -60,-165 -60,-162.5 -60,-160 -60,-157.5 -60,-155 -60,-155 -61.76,-155 -63.52,-155 -65.28,-155 -67.04,-155 -68.8,-155 -70.56,-155 -72.32,-155 -74.08,-155 -75.84,-155 -77.6,-157.5 -77.6,-160 -77.6,-162.5 -77.6,-165 -77.6,-167.5 -77.6,-170 -77.6,-172.5 -77.6,-175 -77.6,-177.5 -77.6,180 -77.6,178.5 -77.6,177 -77.6,175.5 -77.6,174 -77.6,172.5 -77.6,171 -77.6,169.5 -77.6,168 -77.6,166.5 -77.6,165 -77.6,165 -75.84,165 -74.08,165 -72.32,165 -70.56,165 -68.8,165 -67.04,165 -65.28,165 -63.52,165 -61.76,165 -60,166.5 -60,168 -60,169.5 -60,171 -60,172.5 -60,174 -60,175.5 -60,177 -60,178.5 -60,-180 -60))", "dataset_titles": "Access to data; Adelie penguin banding data 1994-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science; Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "datasets": [{"dataset_uid": "601443", "doi": "10.15784/601443", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Penguin; Ross Sea; Seabirds", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin banding data 1994-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601443"}, {"dataset_uid": "001368", "doi": "", "keywords": null, "people": null, "repository": "CADC", "science_program": null, "title": "Access to data", "url": "http://data.prbo.org/apps/penguinscience/AllData/mammals"}, {"dataset_uid": "601444", "doi": "10.15784/601444", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Mark-Recapture; Monitoring; Penguin; Ross Island", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601444"}], "date_created": "Tue, 19 May 2009 00:00:00 GMT", "description": "This project is an international collaborative investigation of geographic structuring, founding of new colonies, and population change of Adelie penguins (Pygoscelis adelia) nesting on Ross and Beaufort islands, Antarctica. The long-term changes occurring at these colonies are representative of changes throughout the Ross Sea, where 30% of all Adelie penguins reside, and are in some way related to changing climate. The recent grounding of two very large icebergs against Ross and Beaufort islands, with associated increased variability in sea-ice extent, has provided an unparalleled natural experiment affecting wild, interannual swings in colony productivity, foraging effort, philopatry and recruitment. Results of this natural experiment can provide insights into the demography and geographic population structuring of this species, having relevance Antarctic-wide in understanding its future responses to climate change as well as interpreting its amazingly well known Holocene history. This ongoing study will continue to consider the relative importance of resources that constrain or enhance colony growth (nesting habitat, access to food); the aspects of natural history that are affected by exploitative or interference competition among neighboring colonies (breeding success, foraging effort); climatic factors that influence the latter, especially sea ice patterns; and behavioral mechanisms that influence colony growth as a function of initial size and location (emigration, immigration). An increased effort will focus on understanding factors that affect over-winter survival. The hypothesis is that the age structure of Cape Crozier has changed over the past thirty years and no longer reflects the smaller colonies nearby. Based on recent analyses, it appears that the Ross Island penguins winter in a narrow band of sea ice north of the Antarctic Circle (where daylight persists) and south of the southern boundary of the Antarctic Circumpolar Current (where food abounds). More extensive winter ice takes the penguins north of that boundary where they incur higher mortality. Thus, where a penguin winters may be due to the timing of its post-breeding departure (which differs among colonies), which affects where it first encounters sea ice on which to molt and where it will be transported by the growing ice field. Foraging effort and interference competition for food suggested as factors driving the geographic structuring of colonies. The research includes a census of known-age penguins, studies of foraging effort and overlap among colonies; and identification of the location of molting and wintering areas. Information will be related to sea-ice conditions as quantified by satellite images. Demographic and foraging-effort models will be used to synthesize results. The iceberg natural experiment is an unparalleled opportunity to investigate the demographics of a polar seabird and its response to climate change. The marked, interannual variability in apparent philopatry, with concrete data being collected on its causes, is a condition rarely encountered among studies of vertebrates. Broader impacts include collaborating with New Zealand and Italian researchers, involving high school teachers and students in the fieldwork and continuing a website to highlight results to both scientists and the general public.", "east": -155.0, "geometry": "POINT(-175 -68.8)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ballard, Grant", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "CADC; USAP-DC", "science_programs": null, "south": -77.6, "title": "COLLABORATIVE: Geographic Structure of Adelie Penguin Colonies - Demography of Population Change", "uid": "p0000068", "west": 165.0}, {"awards": "0440478 Tang, Kam", "bounds_geometry": "POINT(166.66267 -77.85067)", "dataset_titles": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial Forms of Phaeocystis Antarctica", "datasets": [{"dataset_uid": "600043", "doi": "10.15784/600043", "keywords": "Biota; McMurdo Sound; Oceans; Phytoplankton; Ross Sea; Southern Ocean; Zooplankton", "people": "Smith, Walker; Tang, Kam", "repository": "USAP-DC", "science_program": null, "title": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial Forms of Phaeocystis Antarctica", "url": "https://www.usap-dc.org/view/dataset/600043"}], "date_created": "Mon, 04 May 2009 00:00:00 GMT", "description": "Phaeocystis Antarctica is a widely distributed phytoplankton that forms dense blooms and aggregates in the Southern Ocean. This phytoplankton and plays important roles in polar ecology and biogeochemistry, in part because it is a dominant primary producer, a main component of organic matter vertical fluxes, and the principal producer of volatile organic sulfur in the region. Yet P. Antarctica is also one of the lesser known species in terms of its physiology, life history and trophic relationships with other organisms; furthermore, information collected on other Phaeocystis species and from different locations may not be applicable to P. Antarctica in the Ross Sea. P. Antarctica occurs mainly as two morphotypes: solitary cells and mucilaginous colonies, which differ significantly in size, architecture and chemical composition. Relative dominance between solitary cells and colonies determines not only the size spectrum of the population, but also its carbon dynamics, nutrient uptake and utilization. Conventional thinking of the planktonic trophic processes is also challenged by the fact that colony formation could effectively alter the predator-prey interactions and interspecific competition. However, the factors that regulate the differences between solitary and colonial forms of P. Antarctica are not well-understood. The research objective of this proposal is therefore to address these over-arching questions:\u003cbr/\u003eo Do P. Antarctica solitary cells and colonies differ in growth, composition and\u003cbr/\u003ephotosynthetic rates?\u003cbr/\u003eo How do nutrients and grazers affect colony development and size distribution of P. \u003cbr/\u003eAntarctica?\u003cbr/\u003eo How do nutrients and grazers act synergistically to affect the long-term population\u003cbr/\u003edynamics of P. Antarctica? Experiments will be conducted in the McMurdo station with natural P. Antarctica assemblages and co-occurring grazers. Laboratory experiments will be conducted to study size-specific growth and photosynthetic rates of P. Antarctica, size-specific grazing mortality due to microzooplankton and mesozooplankton, the effects of macronutrients on the (nitrogen compounds) relative dominance of solitary cells and colonies, and the effects of micronutrient (Fe) and grazing related chemical signals on P. Antarctica colony development. Because this species is of critical importance in the Southern Ocean, and because this research will provide critical information on factors that regulate the role of P.Antarctica in food webs and biogeochemical cycles, a major gap in knowledge will be addressed. This project will train two marine science PhD students. The investigators will also collaborate with the School of Education and a marine science museum to communicate polar science to a broader audience.", "east": 166.66267, "geometry": "POINT(166.66267 -77.85067)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.85067, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Tang, Kam; Smith, Walker", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.85067, "title": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial forms of Phaeocystis antarctica", "uid": "p0000214", "west": 166.66267}, {"awards": "0436190 Eastman, Joseph", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Biodiversity, Buoyancy and Morphological Studies of Non-Antarctic Notothenioid Fishes", "datasets": [{"dataset_uid": "600038", "doi": "10.15784/600038", "keywords": "Biota; NBP0404; Oceans; R/v Nathaniel B. Palmer; Southern Ocean", "people": "Eastman, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Biodiversity, Buoyancy and Morphological Studies of Non-Antarctic Notothenioid Fishes", "url": "https://www.usap-dc.org/view/dataset/600038"}], "date_created": "Mon, 30 Mar 2009 00:00:00 GMT", "description": "Patterns of biodiversity, as revealed by basic research in organismal biology, may be derived from ecological and evolutionary processes expressed in unique settings, such as Antarctica. The polar regions and their faunas are commanding increased attention as declining species diversity, environmental change, commercial fisheries, and resource management are now being viewed in a global context. Commercial fishing is known to have a direct and pervasive effect on marine biodiversity, and occurs in the Southern Ocean as far south as the Ross Sea. \u003cbr/\u003eThe nature of fish biodiversity in the Antarctic is different than in all other ocean shelf areas. Waters of the Antarctic continental shelf are ice covered for most of the year and water temperatures are nearly constant at -1.5 C. In these waters components of the phyletically derived Antarctic clade of Notothenioids dominate fish diversity. In some regions, including the southwestern Ross Sea, Notothenioids are overwhelmingly dominant in terms of number of species, abundance, and biomass. Such dominance by a single taxonomic group is unique among shelf faunas of the world. In the absence of competition from a taxonomically diverse fauna, Notothenioids underwent a habitat or depth related diversification keyed to the utilization of unfilled niches in the water column, especially pelagic or partially pelagic zooplanktivory and piscivory. This has been accomplished in the absence of a swim bladder for buoyancy control. They also may form a special type of adaptive radiation known as a species flock, which is an assemblage of a disproportionately high number of related species that have evolved rapidly within a defined area where most species are endemic. Diversification in buoyancy is the hallmark of the notothenioid radiation. Buoyancy is the feature of notothenioid biology that determines whether a species lives on the substrate, in the water column or both. Buoyancy also influences other key aspects of life history including swimming, feeding and reproduction and thus has implications for the role of the species in the ecosystem. \u003cbr/\u003eWith similarities to classic evolutionary hot spots, the Antarctic shelf and its Notothenioid radiation merit further exploration. The 2004 \"International Collaborative Expedition to collect and study Fish Indigenous to Sub-Antarctic Habitats,\" or, \"ICEFISH,\" provided a platform for collection of notothenioid fishes from sub-Antarctic waters between South America and Africa, which will be examined in this project. This study will determine buoyancy for samples of all notothenioid species captured during the ICEFISH cruise. This essential aspect of the biology is known for only 19% of the notothenioid fauna. Also, the gross and microscopic anatomy of brains and sense organs of the phyletically basal families Bovichtidae, Eleginopidae, and of the non-Antarctic species of the primarily Antarctic family Nototheniidae will be examined. The fish biodiversity and endemicity in poorly known localities along the ICEFISH cruise track, seamounts and deep trenches will be quantified. Broader impacts include improved information for comprehending and conserving biodiversity, a scientific and societal priority.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Eastman, Joseph", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Biodiversity, Buoyancy and Morphological Studies of Non-Antarctic Notothenioid Fishes", "uid": "p0000106", "west": -180.0}, {"awards": "0338342 Foreman, Christine; 0338260 Chin, Yu-Ping", "bounds_geometry": "POINT(166.167 -77.55)", "dataset_titles": "Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island", "datasets": [{"dataset_uid": "600168", "doi": "10.15784/600168", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Critical Zone; Ross Island; Sample/collection Description; Sample/Collection Description; Water Samples", "people": "Chin, Yu-Ping; Foreman, Christine", "repository": "USAP-DC", "science_program": null, "title": "Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island", "url": "https://www.usap-dc.org/view/dataset/600168"}], "date_created": "Mon, 16 Mar 2009 00:00:00 GMT", "description": "Dissolved organic matter (DOM) is a significant chemical component in aquatic systems because it acts as an important carbon source for microorganisms, absorbs harmful radiation in sunlight, is able to complex metals, and can participate in important biogeochemical reactions. This study will investigate the biogeochemical cycling of DOM in a small coastal Antarctic pond, Pony Lake, located on Cape Royds, Ross Island. Because there are no higher plants present at this site all of the DOM in this lake is derived from microorganisms. Thus, Pony Lake is an ideal site to study the effect of physical, chemical, and microbial processes on the composition and character of the DOM pool. Finally, Pony Lake is also an ideal site to collect an International Humic Substances Society (IHSS) fulvic acid standard. Unlike other IHSS standards, this standard will not contain DOM components derived from higher land plants. To better understand the role of physical influences, the project will study the changes in the DOM pool as the lake evolves from ice-covered to ice-free conditions during the summer, as well as the relationship of DOM to the observed turnover of dominant microbial communities in the lake. Scientists will also monitor changes in microbial abundance, diversity, and productivity that may occur during the ice to open-water transition period. This research will provide much needed information regarding the relationship between microbial diversity and DOM biogeochemistry. Middle school science students will be active participants in this project through the Internet, while scientists are in the field, and in the lab.", "east": 166.167, "geometry": "POINT(166.167 -77.55)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; FIELD SURVEYS", "locations": null, "north": -77.55, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Foreman, Christine; Chin, Yu-Ping", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.55, "title": "Collaborative Research: Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island", "uid": "p0000548", "west": 166.167}, {"awards": "0742057 Gallager, Scott", "bounds_geometry": "POLYGON((-168.291 -64.846,-165.018 -64.846,-161.745 -64.846,-158.472 -64.846,-155.199 -64.846,-151.926 -64.846,-148.653 -64.846,-145.38 -64.846,-142.107 -64.846,-138.834 -64.846,-135.561 -64.846,-135.561 -66.0269,-135.561 -67.2078,-135.561 -68.3887,-135.561 -69.5696,-135.561 -70.7505,-135.561 -71.9314,-135.561 -73.1123,-135.561 -74.2932,-135.561 -75.4741,-135.561 -76.655,-138.834 -76.655,-142.107 -76.655,-145.38 -76.655,-148.653 -76.655,-151.926 -76.655,-155.199 -76.655,-158.472 -76.655,-161.745 -76.655,-165.018 -76.655,-168.291 -76.655,-168.291 -75.4741,-168.291 -74.2932,-168.291 -73.1123,-168.291 -71.9314,-168.291 -70.7505,-168.291 -69.5696,-168.291 -68.3887,-168.291 -67.2078,-168.291 -66.0269,-168.291 -64.846))", "dataset_titles": "SGER: Primary and Secondary Production and Carbon Flux Through the Microbial Community Along the Western Antarctic Marginal Ice Zone on the Oden Southern Ocean 2007 Expeditions", "datasets": [{"dataset_uid": "600086", "doi": "10.15784/600086", "keywords": "Amundsen Sea; Biota; Microbiology; Navigation; Oceans; Oden; OSO2007; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Dennett, Mark; Gallager, Scott", "repository": "USAP-DC", "science_program": null, "title": "SGER: Primary and Secondary Production and Carbon Flux Through the Microbial Community Along the Western Antarctic Marginal Ice Zone on the Oden Southern Ocean 2007 Expeditions", "url": "https://www.usap-dc.org/view/dataset/600086"}], "date_created": "Mon, 16 Mar 2009 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe research will continue and extend the study in the Southern Ocean that was initiated during the Oden Southern Ocean 2006 expedition in collaboration with Swedish scientist Mellissa Chierici. We will quantify carbon flux through the food web in the marginal ice zone (MIZ) by measuring size fractionated primary and secondary production, grazing and carbon flux through nanoplankton (2-20 um), microplankton (20-200um), and mesoplankton (200-2000 um). Community structure, species abundance and size specific grazing rates will be quantified using a variety of techniques both underway and at ice stations along the MIZ. The proposed cruise track extends across the Drake Passage to the Western Antarctic Peninsula (WAP) with three station transects along a gradient from the open ocean through the marginal ice zone (MIZ) in the Bellinghausen and Amundsen Seas and into the Ross Sea Polynya. Ice stations along each transect will provide material to characterize production associated with annual ice. Underway measurements of primary and secondary production (chlorophyll, CDOM, microplankton, and mesoplankton) and hydrography (temperature, salinity, pH, DO, turbidity) will establish a baseline for future cruises and as support for other projects such as biogeochemical studies on carbon dioxide drawdown and trace metal work on primary production. The outcome of these measurements will be a description of nano to mesoplankton standing stocks, community structure, and carbon flux along the MIZ in the Bellinghausen and Amundsen Seas and the Ross Sea Polynya.", "east": -135.561, "geometry": "POINT(-151.926 -70.7505)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -64.846, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gallager, Scott; Dennett, Mark", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.655, "title": "SGER: Primary and Secondary Production and Carbon Flux Through the Microbial Community Along the Western Antarctic Marginal Ice Zone on the Oden Southern Ocean 2007 Expeditions", "uid": "p0000563", "west": -168.291}, {"awards": "0741403 Sherrell, Robert", "bounds_geometry": "POLYGON((-180 -69,-172.5 -69,-165 -69,-157.5 -69,-150 -69,-142.5 -69,-135 -69,-127.5 -69,-120 -69,-112.5 -69,-105 -69,-105 -69.9,-105 -70.8,-105 -71.7,-105 -72.6,-105 -73.5,-105 -74.4,-105 -75.3,-105 -76.2,-105 -77.1,-105 -78,-112.5 -78,-120 -78,-127.5 -78,-135 -78,-142.5 -78,-150 -78,-157.5 -78,-165 -78,-172.5 -78,180 -78,178.8 -78,177.6 -78,176.4 -78,175.2 -78,174 -78,172.8 -78,171.6 -78,170.4 -78,169.2 -78,168 -78,168 -77.1,168 -76.2,168 -75.3,168 -74.4,168 -73.5,168 -72.6,168 -71.7,168 -70.8,168 -69.9,168 -69,169.2 -69,170.4 -69,171.6 -69,172.8 -69,174 -69,175.2 -69,176.4 -69,177.6 -69,178.8 -69,-180 -69))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 10 Mar 2009 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe research objective is (1) to determine the distributions and dynamics of a full suite of bioactive trace metals in dissolved and suspended particulate forms, along sampling transects of the Amundsen and Ross Seas. And (2) to test the sensitivity of overall cellular metal stoichiometry (metal/carbon ratios) to natural gradients in species assemblage and Fe availability. Our earlier findings from a single Ross Sea station and from a Drake Passage crossing suggest that Fe-limited phytoplankton cells are unusually enriched in Zn, Cu and Cd relative to biomass carbon, with strong implications for the biogeochemical cycling of these elements relative to carbon fluxes in the Southern Ocean. In collaboration with other researchers on the cruise, we will also measure metal stoichiometry of cells exposed to predicted 2010 temperature and carbon dioxide levels in shipboard incubation studies, as a window into possible effects of climate change on metals biogeochemistry in these regions. This proposal will support close international collaborations and lasting infrastructure development as US and Swedish scientists, and more importantly, their students, work toward shared the shared goal of understanding a region that is experiencing one of the fastest rates of climate change on the globe. Trace metal micro-nutrients are a key control on the productivity of Antarctic marine ecosystems. Our results will be made widely available through research publications and internet-available databases, and public outreach through COSEE at Rutgers University.", "east": -105.0, "geometry": "POINT(-148.5 -73.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -69.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Sherrell, Robert", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -78.0, "title": "SGER: Science-of-Opportunity Aboard Icebreaker Oden: Bioactive trace metals in the Amundsen and Ross Seas", "uid": "p0000561", "west": 168.0}, {"awards": "9911617 Blankenship, Donald; 9319379 Blankenship, Donald", "bounds_geometry": null, "dataset_titles": "Antarctic Aerogeophysics Data; Antarctic Subglacial Lake Classification Inventory; RBG - Robb Glacier Survey; SOAR-Lake Vostok Survey airborne radar data; SOAR-Lake Vostok Survey bed elevation data; SOAR-Lake Vostok Survey Gravity data; SOAR-Lake Vostok Survey ice thickness data; SOAR-Lake Vostok survey magnetic anomaly data; SOAR-Lake Vostok Survey surface elevation data", "datasets": [{"dataset_uid": "601297", "doi": "10.1594/IEDA/306567", "keywords": "Airborne Laser Altimeters; Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Sheet; Ice Stratigraphy; Ice Thickness; Ice Thickness Distribution; Lake Vostok; Radar; Radar Altimetry; Radar Echo Sounder; SOAR; Subglacial Lake", "people": "Bell, Robin; Studinger, Michael S.", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey ice thickness data", "url": "https://www.usap-dc.org/view/dataset/601297"}, {"dataset_uid": "601298", "doi": "10.1594/IEDA/306566", "keywords": "Airborne Altimetry; Airborne Laser Altimeters; Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Ice Sheet Elevation; Ice Surface; Lake Vostok; Radar Echo Sounder; SOAR; Surface Elevation", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey surface elevation data", "url": "https://www.usap-dc.org/view/dataset/601298"}, {"dataset_uid": "601296", "doi": " 10.1594/IEDA/306564", "keywords": "Airborne Magnetic; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Lake Vostok; Magnetic; Magnetic Anomaly; Magnetometer; Potential Field; SOAR; Solid Earth", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok survey magnetic anomaly data", "url": "https://www.usap-dc.org/view/dataset/601296"}, {"dataset_uid": "601295", "doi": "10.1594/IEDA/306563", "keywords": "Airborne Gravity; Airplane; Antarctica; East Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Lake Vostok; Potential Field; Solid Earth", "people": "Bell, Robin; Studinger, Michael S.", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey Gravity data", "url": "https://www.usap-dc.org/view/dataset/601295"}, {"dataset_uid": "609240", "doi": "", "keywords": "Airborne Radar; Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Navigation; Potential Field; SOAR; Solid Earth", "people": "Morse, David L.; Blankenship, Donald D.; Dalziel, Ian W.; Holt, John W.", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Aerogeophysics Data", "url": "https://www.usap-dc.org/view/dataset/609240"}, {"dataset_uid": "601299", "doi": "10.1594/IEDA/306565", "keywords": "Airborne Laser Altimeters; Airborne Laser Altimetry; Airborne Radar; Airplane; Antarctica; Bed Elevation; Bedrock Elevation; Digital Elevation Model; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Lake Vostok; Radar; Radar Echo Sounder; SOAR", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey bed elevation data", "url": "https://www.usap-dc.org/view/dataset/601299"}, {"dataset_uid": "601604", "doi": "10.15784/601604", "keywords": "Airborne Radar; Antarctica; Bed Elevation; Geophysics; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Surface Elevation; Ice Thickness; Robb Glacier; Transantarctic Mountains", "people": "Blankenship, Donald D.; Young, Duncan A.; Buck, W. Roger; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "RBG - Robb Glacier Survey", "url": "https://www.usap-dc.org/view/dataset/601604"}, {"dataset_uid": "601300", "doi": "10.1594/IEDA/306568", "keywords": "Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Lake Vostok; Navigation; Radar; SOAR; Subglacial Lakes", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey airborne radar data", "url": "https://www.usap-dc.org/view/dataset/601300"}, {"dataset_uid": "609336", "doi": "10.7265/N5CN71VX", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Subglacial Lake", "people": "Blankenship, Donald D.; Carter, Sasha P.; Holt, John W.", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Subglacial Lake Classification Inventory", "url": "https://www.usap-dc.org/view/dataset/609336"}], "date_created": "Fri, 06 Feb 2009 00:00:00 GMT", "description": "9911617\u003cbr/\u003eBlankenship\u003cbr/\u003e\u003cbr/\u003eThis award, provided jointly by the Antarctic Geology and Geophysics Program, the Antarctic Glaciology Program, and the Polar Research Support Section of the Office of Polar Programs, provides funds for continuation of the Support Office for Aerogeophysical Research (SOAR). From July 1994 to July 2000, SOAR served as a facility to accomplish aerogeophysical research in Antarctica under an agreement between the University of Texas at Austin and the National Science Foundation\u0027s Office of Polar Programs (NSF/OPP). SOAR operated and maintained an aerogeophysical instrument package that consists of an ice-penetrating radar sounder, a laser altimeter, a gravimeter and a magnetometer that are tightly integrated with each other as well as with the aircraft\u0027s avionics and power packages. An array of aircraft and ground-based GPS receivers supported kinematic differential positioning using carrier-phase observations. SOAR activities included: developing aerogeophysical research projects with NSF/OPP investigators; upgrading of the aerogeophysical instrumentation package to accommodate new science projects and advances in technology; fielding this instrument package to accomplish SOAR-developed projects; and management, reduction, and analysis of the acquired aerogeophysical data. In pursuit of 9 NSF-OPP funded aerogeophysical research projects (involving 14 investigators from 9 institutions), SOAR carried out six field campaigns over a six-year period and accomplished approximately 200,000 line kilometers of aerogeophysical surveying over both East and West Antarctica in 377 flights.\u003cbr/\u003e\u003cbr/\u003eThis award supports SOAR to undertake a one year and 8 month program of aerogeophysical activities that are consistent with continuing U.S. support for geophysical research in Antarctica. \u003cbr/\u003e- SOAR will conduct an aerogeophysical campaign during the 200/01 austral summer to accomplish surveys for two SOAR-developed projects: \"Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Studies\" (Co-PI\u0027s Bell and Studinger, LDEO); and \"Collaborative Research: Seismic Investigation of the Deep Continental Structure Across the East-West Antarctic Boundary\" (Co-PI\u0027s Weins, Washington U. and Anandakrishnan, U. Alabama). After configuration and testing of the survey aircraft in McMurdo, SOAR will conduct survey flights from an NSF-supported base adjacent to the Russian Station above Lake Vostok and briefly occupy one or two remote bases on the East Antarctic ice sheet.\u003cbr/\u003e- SOAR will reduce these aerogeophysical data and produce profiles and maps of surface elevation, bed elevation, gravity and magnetic field intensity. These results will be provided to the respective project investigators within nine months of conclusion of field activities. We will also submit a technical manuscript that describes these results to a refereed scientific journal and distribute these results to appropriate national geophysical data centers within approximately 24 months of completion of field activities.\u003cbr/\u003e- SOAR will standardize all previously reduced SOAR data products and transfer them to the appropriate national geophysical data centers by the end of this grant.\u003cbr/\u003e- SOAR will convene a workshop to establish a community consensus for future U.S. Antarctic aerogeophysical research. This workshop will be co-convened by Ian Dalziel and Richard Alley and will take place during the spring of 2001.\u003cbr/\u003e- SOAR will upgrade the existing SOAR in-field quality control procedures to serve as a web-based interface for efficient browsing of many low-level SOAR data streams.\u003cbr/\u003e- SOAR will repair and/or refurbish equipment that was used during the 2000/01 field campaign.\u003cbr/\u003e\u003cbr/\u003eSupport for SOAR is essential for accomplishing major geophysical investigations in Antarctica. Following data interpretation by the science teams, these data will provide valuable insights to the structure and evolution of the Antarctic continent.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e IMAGING RADAR SYSTEMS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LIDAR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e MAGNETIC FIELD/ELECTRIC FIELD INSTRUMENTS \u003e PROTON MAGNETOMETER", "is_usap_dc": true, "keywords": "Ice Sheet; Ice Sheet Elevation; Surface Winds; Snow Temperature; Atmospheric Pressure; Antarctic; West Antarctic Ice Sheet; Surface Temperature Measurements; FIELD INVESTIGATION; Surface Wind Speed Measurements; Subglacial Topography; Atmospheric Humidity Measurements; Not provided; Aerogeophysics; FIELD SURVEYS; GROUND STATIONS; Antarctica; SOAR; Snow Temperature Measurements; West Antarctica; Antarctic Ice Sheet; East Antarctic Plateau", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet; West Antarctica; West Antarctic Ice Sheet; East Antarctic Plateau", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": null, "persons": "Carter, Sasha P.; Holt, John W.; Blankenship, Donald D.; Morse, David L.; Dalziel, Ian W.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)", "uid": "p0000125", "west": null}, {"awards": "0125098 Emslie, Steven", "bounds_geometry": "POLYGON((-50 -60,-29 -60,-8 -60,13 -60,34 -60,55 -60,76 -60,97 -60,118 -60,139 -60,160 -60,160 -63,160 -66,160 -69,160 -72,160 -75,160 -78,160 -81,160 -84,160 -87,160 -90,139 -90,118 -90,97 -90,76 -90,55 -90,34 -90,13 -90,-8 -90,-29 -90,-50 -90,-50 -87,-50 -84,-50 -81,-50 -78,-50 -75,-50 -72,-50 -69,-50 -66,-50 -63,-50 -60))", "dataset_titles": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region", "datasets": [{"dataset_uid": "600028", "doi": "10.15784/600028", "keywords": "Antarctica; Biota; Geochronology; Oceans; Paleoclimate; Penguin; Radiocarbon; Ross Sea; Southern Ocean", "people": "Emslie, Steven", "repository": "USAP-DC", "science_program": null, "title": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region", "url": "https://www.usap-dc.org/view/dataset/600028"}], "date_created": "Sun, 01 Feb 2009 00:00:00 GMT", "description": "#0125098\u003cbr/\u003eSteve Emslie\u003cbr/\u003e\u003cbr/\u003eOccupation History and Diet of Adelie Penguins in the Ross Sea Region\u003cbr/\u003e\u003cbr/\u003eThis project will build on previous studies to investigate the occupation history and diet of Adelie penguins (Pygoscelis adeliae) in the Ross Sea region, Antarctica, with excavations of abandoned and active penguin colonies. Numerous active and abandoned colonies exist on the Victoria Land coast, from Cape Adare to Marble Point will be sampled. Some of these sites have been radiocarbon-dated and indicate a long occupation history for Adelie penguins extending to 13,000 years before present (B. P.). The material recovered from excavations, as demonstrated from previous investigations, will include penguin bones, tissue, and eggshell fragments as well as abundant remains of prey (fish bones, otoliths, squid beaks) preserved in ornithogenic (formed from bird guano) soils. These organic remains will be quantified and subjected to radiocarbon analyses to obtain a colonization history of penguins in this region. Identification of prey remains in the sediments will allow assessment of penguin diet. Other data (ancient DNA) from these sites will be analyzed through collaboration with New Zealand scientists. Past climatic conditions will be interpreted from published ice-core and marine-sediment records. These data will be used to test the hypothesis that Adelie penguins respond to climate change, past and present, in a predictable manner. In addition, the hypothesis that Adelie penguins alter their diet in accordance with climate, sea-ice conditions, and other marine environmental variables along a latitudinal gradient will be tested. Graduate and undergraduate students will be involved in this project and a project Web site will be developed to report results and maintain educational interaction between the PI and students at local middle and high schools in Wilmington, NC.", "east": 160.0, "geometry": "POINT(55 -75)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Emslie, Steven", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region", "uid": "p0000220", "west": -50.0}, {"awards": "0538266 Castillo, Paterno", "bounds_geometry": "POLYGON((171.82 -69.84,171.987 -69.84,172.154 -69.84,172.321 -69.84,172.488 -69.84,172.655 -69.84,172.822 -69.84,172.989 -69.84,173.156 -69.84,173.323 -69.84,173.49 -69.84,173.49 -70.007,173.49 -70.174,173.49 -70.341,173.49 -70.508,173.49 -70.675,173.49 -70.842,173.49 -71.009,173.49 -71.176,173.49 -71.343,173.49 -71.51,173.323 -71.51,173.156 -71.51,172.989 -71.51,172.822 -71.51,172.655 -71.51,172.488 -71.51,172.321 -71.51,172.154 -71.51,171.987 -71.51,171.82 -71.51,171.82 -71.343,171.82 -71.176,171.82 -71.009,171.82 -70.842,171.82 -70.675,171.82 -70.508,171.82 -70.341,171.82 -70.174,171.82 -70.007,171.82 -69.84))", "dataset_titles": "Samples collected during NBP0701 cruise in the Ross Sea", "datasets": [{"dataset_uid": "000135", "doi": "", "keywords": null, "people": null, "repository": "EarthChem", "science_program": null, "title": "Samples collected during NBP0701 cruise in the Ross Sea", "url": "http://dx.doi.org/10.1594/IEDA/100055"}], "date_created": "Tue, 30 Dec 2008 00:00:00 GMT", "description": "This award supports the study of lava samples from seamounts in the Cape Adare region of the western Ross Sea. Volcanism in this area is poorly understood, and the geochemistry of these lavas may offer new insight into regional geodynamics and global mantle geochemistry. Because the Cape Adare seamounts are located on oceanic lithosphere, they may be free of the contamination that affects lavas erupted through continental areas. This one-year investigation will gather data on samples collected on a cruise to this region in 2007. It will determine seamount ages, characterize their mantle sources, assess models for their origin, and judge the potential for more detailed study. In terms of broader impacts, this project will involve graduate and undergraduate students in an exciting field expedition, followed by laboratory work using cutting-edge techniques for geochemical analyses.", "east": 173.49, "geometry": "POINT(172.655 -70.675)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -69.84, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Castillo, Paterno; Cande, Steven", "platforms": "Not provided", "repo": "EarthChem", "repositories": "EarthChem", "science_programs": null, "south": -71.51, "title": "Collaborative Research: Constraining the Petrogenesis and Mantle Source of Adare Basin Seamount Lavas", "uid": "p0000222", "west": 171.82}, {"awards": "0234249 Hollibaugh, James", "bounds_geometry": "POLYGON((-73 -64,-72.1 -64,-71.2 -64,-70.3 -64,-69.4 -64,-68.5 -64,-67.6 -64,-66.7 -64,-65.8 -64,-64.9 -64,-64 -64,-64 -64.4,-64 -64.8,-64 -65.2,-64 -65.6,-64 -66,-64 -66.4,-64 -66.8,-64 -67.2,-64 -67.6,-64 -68,-64.9 -68,-65.8 -68,-66.7 -68,-67.6 -68,-68.5 -68,-69.4 -68,-70.3 -68,-71.2 -68,-72.1 -68,-73 -68,-73 -67.6,-73 -67.2,-73 -66.8,-73 -66.4,-73 -66,-73 -65.6,-73 -65.2,-73 -64.8,-73 -64.4,-73 -64))", "dataset_titles": "Ammonia Oxidizing Bacteria and Archaea Abundance", "datasets": [{"dataset_uid": "000117", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "Ammonia Oxidizing Bacteria and Archaea Abundance", "url": "http://oceaninformatics.ucsd.edu/datazoo/data/pallter/datasets?action=summary\u0026id=114"}], "date_created": "Mon, 01 Dec 2008 00:00:00 GMT", "description": "This project will investigate the distribution, phylogenetic affinities and ecological aspects of ammonium-oxidizing bacteria in the Palmer Long-Term Ecological Research study area. Ammonia oxidation is the first step in the conversion of regenerated nitrogen to dinitrogen gas via denitrification, a 3-step pathway mediated by three distinct guilds of bacteria. As such, ammonia oxidation is important to the global nitrogen cycle. Ammonia oxidation and the overall process of nitrification-denitrification have received little attention in polar oceans where it is significant and where the effects of climate change on biogeochemical rates are likely to be pronounced. The goals of the studies proposed here are A) to obtain more conclusive information concerning composition of Antarctic ammonia oxidizers; B) to begin characterizing their ecophysiology and ecology; and C) to obtain cultures of the organism for more detailed studies. Water column and sea ice AOB assemblages will be characterized phylogenetically and the different kinds of AOB in various samples will be quantified. Nitrification rates will be measured across the LTER study area in water column, sea ice and sediment samples. Grazing rates on AOB will be determined and their sensitivity to UV light evaluated. In addition, the significance of urea nitrogen as a source of reduced nitrogen to AOB will be assessed and the temperature response of nitrification over temperature ranges appropriate to polar regions will be evaluated. This work will provide insights into the ecology of AOB and the knowledge needed to model how water column nitrification will respond to changes in the polar ecosystems accompanying global climate change.", "east": -64.0, "geometry": "POINT(-68.5 -66)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hollibaugh, James T.", "platforms": "Not provided", "repo": "LTER", "repositories": "LTER", "science_programs": "LTER", "south": -68.0, "title": "Distribution And Ecology Of Ammonia Oxidizing Bacteria In The Palmer LTER Study Area", "uid": "p0000225", "west": -73.0}, {"awards": "0741428 Hutchins, David", "bounds_geometry": "POINT(-106 -73)", "dataset_titles": null, "datasets": null, "date_created": "Sun, 23 Nov 2008 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThis Small Grants for Exploratory Research (SGER) proposal describes global change-related experimental research designed to take full advantage of a unique science opportunity on short notice, the leasing of the Oden to conduct ice-breaking operations in McMurdo Sound. \u003cbr/\u003e\u003cbr/\u003eOur emphasis will be on using this opportunistic research platform to ask two questions about present day and future controls on Antarctic margin phytoplankton communities. These are: 1. How will expected alterations in pCO2, pH, and Fe availability in the Southern Ocean, due to future anthropogenic climate change affect phytoplankton species assemblages, carbon and nutrient biogeochemistry, and remineralization processes? 2. What is the current role of organic co-factors (vitamins) in limiting or co-limiting (along with iron ) phytoplankton growth and production in the Antarctic margin? The research approach includes experimental incubations with variation in iron enrichment, carbon dioxide concentration, and temperature. A second suite of experiments will examine co-limitation effects between vitamin B12 and Fe and B12 uptake kinetics. Changes in phytoplankton community structure, and carbon and nutrient cycling will be determined, in collaboration with many of the participating U.S. and Swedish investigators. Together, these two main objectives should allow us to obtain novel insights into the current and future controls on Antarctic margin phytoplankton growth, productivity, and carbon and nutrient biogeochemistry. In particular, the experiments in the Amundsen Sea represent a one-of-a-kind opportunity to understand algal dynamics and potential future responses to climate change in this little-studied ecosystem, and compare these results to those from the better-known Ross Sea. An important result of this study will be to build strong international collaborations with the Swedish marine science community. Additional broader impacts include participatin of an Hispanic Ph.D. student in cruise work and post-cruise analyses, and integration of results into graduate courses at the USC Catalina Lab facility. Public outreach will include presentations on global change impacts on the ocean targeted at audiences ranging from legislators and policymakers to the general public.", "east": -106.0, "geometry": "POINT(-106 -73)", "instruments": null, "is_usap_dc": true, "keywords": "SHIPS", "locations": null, "north": -73.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Hutchins, David", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repositories": null, "science_programs": null, "south": -73.0, "title": "SGER: Science-of-Opportunity Aboard Icebreaker Oden - Phytoplankton Global Change Experiments and Vitamin/Iron Co-Limitation in the Amundsen and Ross Seas", "uid": "p0000224", "west": -106.0}, {"awards": "0440670 Hulbe, Christina; 0440636 Fahnestock, Mark", "bounds_geometry": "POLYGON((-180 -70,-175 -70,-170 -70,-165 -70,-160 -70,-155 -70,-150 -70,-145 -70,-140 -70,-135 -70,-130 -70,-130 -71.6,-130 -73.2,-130 -74.8,-130 -76.4,-130 -78,-130 -79.6,-130 -81.2,-130 -82.8,-130 -84.4,-130 -86,-135 -86,-140 -86,-145 -86,-150 -86,-155 -86,-160 -86,-165 -86,-170 -86,-175 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -84.4,180 -82.8,180 -81.2,180 -79.6,180 -78,180 -76.4,180 -74.8,180 -73.2,180 -71.6,180 -70,180 -70,180 -70,180 -70,180 -70,180 -70,180 -70,180 -70,180 -70,180 -70,-180 -70))", "dataset_titles": "MOA-derived Structural Feature Map of the Ronne Ice Shelf; MOA-derived Structural Feature Map of the Ross Ice Shelf; Using Fracture Patterns and Ice Thickness to Study the History and Dynamics of Grounding Line Migration and Shutdown of Kamb and Whillans Ice Streams", "datasets": [{"dataset_uid": "601432", "doi": "10.15784/601432", "keywords": "Antarctica", "people": "Hulbe, Christina; Forbes, Martin; Ledoux, Christine", "repository": "USAP-DC", "science_program": null, "title": "MOA-derived Structural Feature Map of the Ross Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/601432"}, {"dataset_uid": "609497", "doi": "10.7265/N5PR7SXR", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; MOA; MODIS; Ronne Ice Shelf", "people": "Hulbe, Christina; Ledoux, Christine", "repository": "USAP-DC", "science_program": null, "title": "MOA-derived Structural Feature Map of the Ronne Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/609497"}, {"dataset_uid": "600024", "doi": "", "keywords": null, "people": "Fahnestock, Mark", "repository": "USAP-DC", "science_program": null, "title": "Using Fracture Patterns and Ice Thickness to Study the History and Dynamics of Grounding Line Migration and Shutdown of Kamb and Whillans Ice Streams", "url": "https://www.usap-dc.org/view/dataset/600024"}], "date_created": "Thu, 25 Sep 2008 00:00:00 GMT", "description": "This award supports a three year project to develop the tools required to interpret complex patterns of flow features on the Ross Ice Shelf, which record the discharge history the ice streams flowing east off of the West Antarctic Ice Sheet. This work builds on previous research that used flow features visible in satellite image mosaics and numerical models of ice shelf flow to detect changes in grounding zone dynamics and redirection of ice stream outlets over hundreds of years. Recently observed changes on Whillans Ice Stream fit within this framework. The pattern of redirection is driven by the influence of rapid downstream thinning on the basal thermal gradient in the ice and associated \"sticky spot\" (ice rise) formation. In pursuing this work, the investigators recognized other records of discharge variation on the shelf that can be used to build a more complete history and understanding of ice-stream discharge variability. The intellectual merit of the proposed work lies in the fact that these records, including fracture patterns and spatial variation in ice thickness, when understood in the proper context, will yield quantitative information about the timing and dynamics of ice stream slowdowns, grounding line retreat, and the relative history of discharge between the ice streams. New tools will help further constrain this history. The laser altimeter on NASA\u0027s IceSAT has improved our knowledge of the surface elevation of Antarctic ice. IceSAT surface elevations provide a high-resolution map of ice-shelf thickness that, along with provenance maps from ice-shelf image mosaics, will be used to estimate the volumes of ice involved in past ice-stream discharge events (slowdowns, redirections, and so on). This project will develop new numerical models for fracture propagation; these will allow past variations in ice-shelf stress state to be investigated. Together, the dynamic and volume-flux histories will provide a powerful set of observations for understanding past variations in ice stream discharge and the underlying physical processes. The broader impacts of this project center on how it contributes to the ability to estimate West Antarctic contributions to global sea level rise and to answer outstanding questions about the causes of millennial and longer-scale evolution of ice streams. This work will provide a history of the most complex record of ice discharge known. In addition to the incorporation of this research into graduate student advising and normal teaching duties, the investigators are involved in other avenues of civic engagement and education. Outreach to high school students and the community at large is promoted on an annual basis by the investigators at both institutions. New outreach projects at Portland State University are developed with the assistance of researchers with expertise in student learning and achievement in science and mathematics. The collaborative research team includes two glaciologists with experience in the pairing of high resolution satellite imagery and a variety of ice-flow models and a geologist whose focus is the mechanics of rock deformation.", "east": -130.0, "geometry": "POINT(-155 -78)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e MODIS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e MODIS", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; Fracture Patterns; Ross Ice Shelf; West Antarctic Ice Sheet; Not provided; Antarctica; TERRA; Ice Sheet; Ice Rise; LABORATORY; Ice-Stream Discharge; West Antarctica; Fracture Propagation; SATELLITES; Ice Stream Motion; Grounding Line; Ice Movement; Ice Stream; Whillans Ice Stream; Ice Stream Outlets; Basal Temperature Gradient; Numerical Model; Ice Thickness; Flow Features; Kamb Ice Stream; Antarctic Ice Sheet; Satellite Image Mosaics; Icesat; Grounding Line Migration; ICESAT", "locations": "Kamb Ice Stream; Whillans Ice Stream; Antarctica; Ross Ice Shelf; West Antarctic Ice Sheet; Antarctic Ice Sheet; West Antarctica", "north": -70.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Hulbe, Christina; Ledoux, Christine; Fahnestock, Mark", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e ICE, CLOUD AND LAND ELEVATION SATELLITE (ICESAT) \u003e ICESAT; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SATELLITES; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e TERRA", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -86.0, "title": "Collaborative Research: Using Fracture Patterns and Ice Thickness to Study the History and Dynamics of Grounding Line Migration and Shutdown of Kamb and Whillans Ice Streams", "uid": "p0000096", "west": 180.0}, {"awards": "0229546 MacAyeal, Douglas", "bounds_geometry": "POINT(-178 -78)", "dataset_titles": "collection of nascent rift images and description of station deployment; Continuous GPS (static) Data from the Ross Ice Shelf, Antarctica; Giant Icebergs of the Ross Sea, in situ Drift and Weather Measurements, Antarctica; Iceberg Firn Temperatures, Antarctica; Iceberg Harmonic Tremor, Seismometer Data, Antarctica; Iceberg Satellite imagery from stations and ice shelves (full data link not provided); Iceberg Tiltmeter Measurements, Antarctica; Ice Shelf Rift Time-Lapse Photography, Antarctica; Incorporated Research Institutions for Seismology; Nascent Iceberg Webcam Images available during the deployment period; Ross Ice Shelf Firn Temperature, Antarctica; The files contain a short header (number of data samples, sample rate, start time, stop time, channel title)The time series data then follow the header above.; This site mirrors the NSIDC website archive.", "datasets": [{"dataset_uid": "609347", "doi": "10.7265/N57W694M", "keywords": "Antarctica; Geodesy; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ross Ice Shelf; Southern Ocean", "people": "MacAyeal, Douglas; Brunt, Kelly; King, Matthew", "repository": "USAP-DC", "science_program": null, "title": "Continuous GPS (static) Data from the Ross Ice Shelf, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609347"}, {"dataset_uid": "609352", "doi": "10.7265/N5M61H55", "keywords": "Glaciology; Iceberg; Oceans; Ross Ice Shelf; Sea Ice; Snow/ice; Snow/Ice; Southern Ocean; Temperature", "people": "Sergienko, Olga; Thom, Jonathan; MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Iceberg Firn Temperatures, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609352"}, {"dataset_uid": "001639", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "collection of nascent rift images and description of station deployment", "url": "http://thistle.org/nascent/index.shtml"}, {"dataset_uid": "609349", "doi": "10.7265/N5445JD6", "keywords": "Geology/Geophysics - Other; Glaciology; Iceberg; Oceans; Ross Sea; Sea Ice; Seismometer; Southern Ocean", "people": "MacAyeal, Douglas; Aster, Richard; Bassis, Jeremy; Okal, Emile", "repository": "USAP-DC", "science_program": null, "title": "Iceberg Harmonic Tremor, Seismometer Data, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609349"}, {"dataset_uid": "609350", "doi": "10.7265/N5VM496K", "keywords": "AWS; Glaciology; GPS; Iceberg; Meteorology; Oceans; Ross Sea; Sea Ice; Southern Ocean; Weatherstation", "people": "Okal, Emile; Bassis, Jeremy; Aster, Richard; MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Giant Icebergs of the Ross Sea, in situ Drift and Weather Measurements, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609350"}, {"dataset_uid": "609351", "doi": "10.7265/N5QV3JGV", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Photo/video; Photo/Video; Ross Ice Shelf", "people": "MacAyeal, Douglas; Brunt, Kelly", "repository": "USAP-DC", "science_program": null, "title": "Ice Shelf Rift Time-Lapse Photography, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609351"}, {"dataset_uid": "002504", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Nascent Iceberg Webcam Images available during the deployment period", "url": "https://amrc.ssec.wisc.edu/data/iceberg.html"}, {"dataset_uid": "609354", "doi": "10.7265/N5BP00Q3", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ross Ice Shelf; Snow/ice; Snow/Ice; Temperature", "people": "Muto, Atsu; MacAyeal, Douglas; Sergienko, Olga; Scambos, Ted", "repository": "USAP-DC", "science_program": null, "title": "Ross Ice Shelf Firn Temperature, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609354"}, {"dataset_uid": "002568", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Iceberg Satellite imagery from stations and ice shelves (full data link not provided)", "url": "http://amrc.ssec.wisc.edu/"}, {"dataset_uid": "001685", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Incorporated Research Institutions for Seismology", "url": "http://www.iris.edu/data/sources.htm"}, {"dataset_uid": "001684", "doi": "", "keywords": null, "people": null, "repository": "AMRDC", "science_program": null, "title": "This site mirrors the NSIDC website archive.", "url": "http://uwamrc.ssec.wisc.edu/"}, {"dataset_uid": "001598", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "The files contain a short header (number of data samples, sample rate, start time, stop time, channel title)The time series data then follow the header above.", "url": "http://nsidc.org"}, {"dataset_uid": "609353", "doi": "10.7265/N5GF0RFF", "keywords": "Glaciology; Iceberg; Oceans; Ross Ice Shelf; Sea Ice; Southern Ocean; Tiltmeter", "people": "MacAyeal, Douglas; Bliss, Andrew; Kim, Young-Jin", "repository": "USAP-DC", "science_program": null, "title": "Iceberg Tiltmeter Measurements, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609353"}], "date_created": "Fri, 19 Sep 2008 00:00:00 GMT", "description": "This award supports the study of the drift and break-up of Earth\u0027s largest icebergs, which were recently released into the Ross Sea of Antarctica as a result of calving from the Ross Ice Shelf. The scientific goals of the study are to determine the physics of iceberg motion within the dynamic context of ocean currents, winds, and sea ice, which determine the forces that drive iceberg motion, and the relationship between the iceberg and geographically and topographically determined pinning points on which the iceberg can ground. In addition, the processes by which icebergs influence the local environments (e.g., sea ice conditions near Antarctica, access to penguin rookeries, air-sea heat exchange and upwelling at iceberg margins, nutrient fluxes) will be studied. The processes by which icebergs generate globally far-reaching ocean acoustic signals that are detected within the global seismic (earthquake) sensing networks will also be studied. A featured element of the scientific research activity will be a field effort to deploy automatic weather stations, seismometer arrays and GPS-tracking stations on several of the largest icebergs presently adrift, or about to be adrift, in the Ross Sea. Data generated and relayed via satellite to home institutions in the Midwest will motivate theoretical analysis and computer simulation; and will be archived on an \"iceberg\" website (http://amrc.ssec.wisc.edu/amrc/iceberg.html) for access by scientists and the general public. At the most broad level, the study is justified by the fact that icebergs released by the Antarctic ice sheet represent the largest movements of fresh water within the natural environment (e.g., several of the icebergs to be studied, B15, C19 and others calved since 2000 CE, represent over 6000 cubic kilometers of fresh water-an amount roughly equivalent to 100 years of the flow of the Nile River). A better understanding of the impact of iceberg drift through the environment, and particularly the impact on ocean stratification and mixing, is essential to the understanding of the abrupt global climate changes witnessed by proxy during the ice age and of concern under conditions of future greenhouse warming. On a more specific level, the study will generate a knowledge base useful for the better management of Antarctic logistical resources (e.g., the shipping lanes to McMurdo Station) that can occasionally be influenced by adverse effects icebergs have on sea ice conditions.", "east": -178.0, "geometry": "POINT(-178 -78)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e HUMIDITY SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e MMS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e TEMPERATURE LOGGERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e TEMPERATURE PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS", "is_usap_dc": true, "keywords": "SEISMOLOGICAL STATIONS; Pressure; AWS; Velocity Measurements; Firn Temperature Measurements; Ice Velocity; Seismology; Ice Sheet Elevation; Harmonic Tremor; Ice Shelf Temperature; Wind Speed; Iceberg; Ice Surface Elevation; Non-Volcanic Tremor; Not provided; Antarctic; Iceberg Tremor; Solar Radiation; Antarctic Ice Sheet; Ross Ice Shelf; Elevation; GPS; Temperature Profiles; Ice Shelf Rift Camera; GROUND STATIONS; Latitude; GROUND-BASED OBSERVATIONS; Ice Shelf Weather; FIELD INVESTIGATION; ARWS; Surface Elevation; Ice Shelf Flow; Antarctica; FIELD SURVEYS; Camera; Seismometer; Iceberg Weather (aws); Ice Movement; Photo; Wind Direction; Iceberg Snow Accumulation; Tremor And Slow Slip Events; AWS Climate Data; Location; Iceberg Drift; Iceberg Collisions; Iceberg Tilt; Atmospheric Pressure; Iceberg Seismicity; Firn Temperature", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet; Ross Ice Shelf", "north": -78.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Okal, Emile; Aster, Richard; Bassis, Jeremy; Kim, Young-Jin; Bliss, Andrew; Sergienko, Olga; Thom, Jonathan; Scambos, Ted; Muto, Atsu; Brunt, Kelly; King, Matthew; Parker, Tim; Okal, Marianne; Cathles, Mac; MacAyeal, Douglas", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e ARWS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e SEISMOLOGICAL STATIONS; Not provided; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "AMRDC; IRIS; NSIDC; Project website; USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research of Earth\u0027s Largest Icebergs", "uid": "p0000117", "west": -178.0}, {"awards": "0338267 Gooseff, Michael", "bounds_geometry": "POLYGON((161.6 -77.4,161.773 -77.4,161.946 -77.4,162.119 -77.4,162.292 -77.4,162.465 -77.4,162.638 -77.4,162.811 -77.4,162.984 -77.4,163.157 -77.4,163.33 -77.4,163.33 -77.435,163.33 -77.47,163.33 -77.505,163.33 -77.54,163.33 -77.575,163.33 -77.61,163.33 -77.645,163.33 -77.68,163.33 -77.715,163.33 -77.75,163.157 -77.75,162.984 -77.75,162.811 -77.75,162.638 -77.75,162.465 -77.75,162.292 -77.75,162.119 -77.75,161.946 -77.75,161.773 -77.75,161.6 -77.75,161.6 -77.715,161.6 -77.68,161.6 -77.645,161.6 -77.61,161.6 -77.575,161.6 -77.54,161.6 -77.505,161.6 -77.47,161.6 -77.435,161.6 -77.4))", "dataset_titles": "Antarctic Hydrologic Margin Microbiology and Biogeochemistry - data; Hydrologic Margins Research Project, 2004-2008, McMurdo Dry Valleys", "datasets": [{"dataset_uid": "000238", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Antarctic Hydrologic Margin Microbiology and Biogeochemistry - data", "url": "http://water.engr.psu.edu/gooseff/web_antarctica/data.html"}, {"dataset_uid": "600016", "doi": "", "keywords": null, "people": "Gooseff, Michael N.", "repository": "USAP-DC", "science_program": null, "title": "Hydrologic Margins Research Project, 2004-2008, McMurdo Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/600016"}], "date_created": "Thu, 11 Sep 2008 00:00:00 GMT", "description": "Aquatic-terrestrial transition zones are crucial environments in understanding the biogeochemistry of landscapes. In temperate watersheds, these areas are generally dominated by riparian zones, which have been identified as regions of special interest for biogeochemistry because of the increased microbial activity in these locations, and because of the importance of these hydrological margins in facilitating and buffering hydrologic and biogeochemical exchanges between terrestrial and aquatic ecosystems. In the Antarctic Dry Valleys, terrestrial-aquatic transition zones are intriguing landscape features because of the vast importance of water in this polar desert, and because the material and energy budgets of dry valley ecosystems are linked by hydrology. Hydrological margins in aquatic-terrestrial transition zones will be studied in the Dry Valleys of Antarctica to answer two overarching questions: (1) what are the major controls over hydrologic and biogeochemical exchange across aquaticterrestrial transition zones and (2) to what extent do trends in nutrient cycling (e.g. nitrogen cycling) across these transition zones reflect differences in microbial communities or function vs. differences in the physical and chemical environment (e.g., redox potential)? The hydrologic gradients that define these interfaces provide the opportunity to assess the relative influence of physical conditions and microbial biodiversity and functioning upon biogeochemical cycling. Coordinated hydrologic, biogeochemical, and molecular microbial studies will be executed within hydrologic margins with the following research objectives: to determine the role of sediment characteristics, permafrost and active layer dynamics, and topography on sub-surface water content and distribution in hydrologic margins, to determine the extent to which transformations of nitrogen in hydrological margins are influenced by physical conditions (i.e., moisture, redox potential and pH) or by the presence of specific microbial communities (e.g., denitrifiers), and to characterize the microbial community structure and function of saturated zones.\u003cbr/\u003e\u003cbr/\u003eThis proposed research will provide an improved understanding of the interaction of liquid water, soils, microbial communities, and biogeochemistry within the important hydrologic margin landscape units of the dry valleys. Dry valleys streams and lakes are unique because there is no influence of higher vegetation on the movement of water and may therefore provide a model system for understanding physical and hydrological influences on microbial ecology and biogeochemistry. Hence the findings will contribute to Antarctic science as well as the broader study of riparian zones and hydrologic margins worldwide. Graduate students and undergraduate students will be involved with fieldwork and research projects. Information will be disseminated through a project web site, and outreach activities will include science education in local elementary, middle and high schools near the three universities involved.", "east": 163.33, "geometry": "POINT(162.465 -77.575)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -77.4, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gooseff, Michael N.; Barrett, John; Takacs-Vesbach, Cristina", "platforms": "Not provided", "repo": "PI website", "repositories": "PI website; USAP-DC", "science_programs": null, "south": -77.75, "title": "Collaborative Research: Hydrologic Controls over Biogeochemistry and Microbial Community Structure and Function across Terrestrial/Aquatic Interfaces in a Polar Desert", "uid": "p0000340", "west": 161.6}, {"awards": "0338218 Halanych, Kenneth; 0338087 Scheltema, Rudolf", "bounds_geometry": "POLYGON((-70 -55,-68 -55,-66 -55,-64 -55,-62 -55,-60 -55,-58 -55,-56 -55,-54 -55,-52 -55,-50 -55,-50 -56,-50 -57,-50 -58,-50 -59,-50 -60,-50 -61,-50 -62,-50 -63,-50 -64,-50 -65,-52 -65,-54 -65,-56 -65,-58 -65,-60 -65,-62 -65,-64 -65,-66 -65,-68 -65,-70 -65,-70 -64,-70 -63,-70 -62,-70 -61,-70 -60,-70 -59,-70 -58,-70 -57,-70 -56,-70 -55))", "dataset_titles": "Expedition Data; Expedition data of LMG0414; Expedition data of LMG0605; Relevance of Planktonic Larval Dispersal to Endemism and Biogeography of Antarctic Benthic Invertebrates", "datasets": [{"dataset_uid": "002711", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0414", "url": "https://www.rvdata.us/search/cruise/LMG0414"}, {"dataset_uid": "600035", "doi": "10.15784/600035", "keywords": "Antarctica; Biota; Oceans; R/v Laurence M. Gould; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Scheltema, Rudolf", "repository": "USAP-DC", "science_program": null, "title": "Relevance of Planktonic Larval Dispersal to Endemism and Biogeography of Antarctic Benthic Invertebrates", "url": "https://www.usap-dc.org/view/dataset/600035"}, {"dataset_uid": "002682", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0605", "url": "https://www.rvdata.us/search/cruise/LMG0605"}, {"dataset_uid": "001565", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0414"}], "date_created": "Wed, 18 Jun 2008 00:00:00 GMT", "description": "Because of extreme isolation of the Antarctic continent since the Early Oligocene, one expects a unique invertebrate benthic fauna with a high degree of endemism. Yet some invertebrate taxa that constitute important ecological components of sedimentary benthic communities include more than 40 percent non-endemic species (e.g., benthic polychaetes). To account for non-endemic species, intermittent genetic exchange must occur between Antarctic and other (e.g. South American) populations. The most likely mechanism for such gene flow, at least for in-faunal and mobile macrobenthos, is dispersal of planktonic larvae across the sub- Antarctic and Antarctic polar fronts. To test for larval dispersal as a mechanism of maintaining genetic continuity across polar fronts, the scientists propose to (1) take plankton samples along transects across Drake passage during both the austral summer and winter seasons while concurrently collecting the appropriate hydrographic data. Such data will help elucidate the hydrographic mechanisms that allow dispersal across Drake Passage. Using a molecular phylogenetic approach, they will (2) compare seemingly identical adult forms from Antarctic and South America continents to identify genetic breaks, historical gene flow, and control for the presence of cryptic species. (3) Similar molecular tools will be used to relate planktonic larvae to their adult forms. Through this procedure, they propose to link the larval forms respectively to their Antarctic or South America origins. The proposed work builds on previous research that provides the basis for this effort to develop a synthetic understanding of historical gene flow and present day dispersal mechanism in South American/Drake Passage/Antarctic Peninsular region. Furthermore, this work represents one of the first attempts to examine recent gene flow in Antarctic benthic invertebrates. Graduate students and a postdoctoral fellow will be trained during this research.", "east": -50.0, "geometry": "POINT(-60 -60)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": true, "keywords": "EU735823-EU735850; R/V LMG; FIELD SURVEYS; Genbank Ef565745-Ef565820; Not provided", "locations": null, "north": -55.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Scheltema, Rudolf; Halanych, Kenneth", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -65.0, "title": "Collaborative Research: Relevance of Planktonic Larval Dispersal to Endemism and Biogeography of Antarctic Benthic Invertebrates", "uid": "p0000189", "west": -70.0}, {"awards": "0127022 Jeffrey, Wade", "bounds_geometry": "POLYGON((-177.639 -43.5676,-143.1091 -43.5676,-108.5792 -43.5676,-74.0493 -43.5676,-39.5194 -43.5676,-4.9895 -43.5676,29.5404 -43.5676,64.0703 -43.5676,98.6002 -43.5676,133.1301 -43.5676,167.66 -43.5676,167.66 -46.99877,167.66 -50.42994,167.66 -53.86111,167.66 -57.29228,167.66 -60.72345,167.66 -64.15462,167.66 -67.58579,167.66 -71.01696,167.66 -74.44813,167.66 -77.8793,133.1301 -77.8793,98.6002 -77.8793,64.0703 -77.8793,29.5404 -77.8793,-4.9895 -77.8793,-39.5194 -77.8793,-74.0493 -77.8793,-108.5792 -77.8793,-143.1091 -77.8793,-177.639 -77.8793,-177.639 -74.44813,-177.639 -71.01696,-177.639 -67.58579,-177.639 -64.15462,-177.639 -60.72345,-177.639 -57.29228,-177.639 -53.86111,-177.639 -50.42994,-177.639 -46.99877,-177.639 -43.5676))", "dataset_titles": "Expedition Data; Ross Sea microbial biomass and production", "datasets": [{"dataset_uid": "600029", "doi": "10.15784/600029", "keywords": "Biota; Chemistry:fluid; Chemistry:Fluid; CTD Data; Microbiology; Oceans; Phytoplankton; Ross Sea; Southern Ocean", "people": "Jeffrey, Wade H.", "repository": "USAP-DC", "science_program": null, "title": "Ross Sea microbial biomass and production", "url": "https://www.usap-dc.org/view/dataset/600029"}, {"dataset_uid": "001584", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0508"}, {"dataset_uid": "001690", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304B"}], "date_created": "Thu, 12 Jun 2008 00:00:00 GMT", "description": "Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea.", "east": 167.66, "geometry": "POINT(-4.9895 -60.72345)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUORESCENCE MICROSCOPY; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e GO-FLO BOTTLES", "is_usap_dc": true, "keywords": "R/V NBP; B-15J", "locations": "B-15J", "north": -43.5676, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Jeffrey, Wade H.; Neale, Patrick", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -77.8793, "title": "Collaborative Proposal: Interactive Effects of UV Radiation and Vertical Mixing on Phytoplankton and Bacterial Productivity of Ross See Phaeocystis Blooms", "uid": "p0000578", "west": -177.639}, {"awards": "0338142 Domack, Eugene; 0338163 Leventer, Amy; 0338220 Ishman, Scott", "bounds_geometry": "POLYGON((-63 -62,-62.3 -62,-61.6 -62,-60.9 -62,-60.2 -62,-59.5 -62,-58.8 -62,-58.1 -62,-57.4 -62,-56.7 -62,-56 -62,-56 -62.5,-56 -63,-56 -63.5,-56 -64,-56 -64.5,-56 -65,-56 -65.5,-56 -66,-56 -66.5,-56 -67,-56.7 -67,-57.4 -67,-58.1 -67,-58.8 -67,-59.5 -67,-60.2 -67,-60.9 -67,-61.6 -67,-62.3 -67,-63 -67,-63 -66.5,-63 -66,-63 -65.5,-63 -65,-63 -64.5,-63 -64,-63 -63.5,-63 -63,-63 -62.5,-63 -62))", "dataset_titles": "Expedition Data; Expedition data of LMG0404; NBP0603 - Expedition Data; NBP0603 - Paleohistory of the Larsen Ice Shelf System", "datasets": [{"dataset_uid": "600027", "doi": "10.15784/600027", "keywords": "ADCP Acoustic Doppler Current Profiler; Antarctic Peninsula; Biota; Diatom; Electromagnetic Data; Flask Glacier; Foehn Winds; Larsen Ice Shelf; Marine Sediments; NBP0603; Oceans; Physical Ice Properties; R/v Nathaniel B. Palmer; Scar Inlet; Southern Ocean", "people": "Domack, Eugene Walter", "repository": "USAP-DC", "science_program": null, "title": "NBP0603 - Paleohistory of the Larsen Ice Shelf System", "url": "https://www.usap-dc.org/view/dataset/600027"}, {"dataset_uid": "002710", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0404", "url": "https://www.rvdata.us/search/cruise/LMG0404"}, {"dataset_uid": "000236", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0603 - Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0603"}, {"dataset_uid": "001610", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0502"}], "date_created": "Wed, 11 Jun 2008 00:00:00 GMT", "description": "The Larsen Ice Shelf is the third largest ice shelf in Antarctica and has continued a pattern of catastrophic decay since the mid 1990\u0027s. The proposed marine geologic work at the Larsen Ice Shelf builds upon our previous NSF-OPP funding and intends to test the working hypothesis that the Larsen B Ice Shelf system has been a stable component of Antarctica\u0027s glacial system since it formed during rising sea levels 10,000 years BP. This conclusion, if supported by observations from our proposed work, is an important first step in establishing the uniqueness and consequences of rapid regional warming currently taking place across the Peninsula. Our previous work in the Larsen A and B embayments has allowed us to recognize the signature of past ice shelf fluctuations and their impact on the oceanographic and biologic environments. We have also overcome many of the limitations of standard radiocarbon dating in Antarctic marine sequences by using variations in the strength of the earth\u0027s magnetic field for correlation of sediment records and by using specific organic compounds (instead of bulk sediment) for radiocarbon dating. We intend to pursue these analytical advances and extend our sediment core stratigraphy to areas uncovered by the most recent collapse of the Larsen B Ice Shelf and areas immediately adjacent to the Larsen C Ice Shelf. In addition to the core recovery program, we intend to utilize our unique access to the ice shelf front to continue our observations of the snow/ice stratigraphy, oceanographic character, and ocean floor character. Sediment traps will also be deployed in order to measure the input of debris from glaciers that are now surging in response to the ice shelf collapse. This proposal is a multi-institutional, international (USAP, Italy, and Canada) effort that combines the established expertise in a variety of disciplines and integrates the research plan into the educational efforts of primarily undergraduate institutions but including some graduate education. This is a three-year project with field seasons planned with flexibility in order to accommodate schedules for the RVIB L.M. Gould. The Antarctic Peninsula is undergoing greater warming than almost anywhere on Earth, perhaps associated with human-induced greenhouse effects. Our proposed work contributes to understanding of these changes where they are occurring first and with greatest magnitude and impact upon the environment.", "east": -56.0, "geometry": "POINT(-59.5 -64.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": true, "keywords": "R/V LMG; R/V NBP; Not provided", "locations": null, "north": -62.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Ishman, Scott; Leventer, Amy; Domack, Eugene Walter", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -67.0, "title": "Collaborative Research: Paleohistory of the Larsen Ice Shelf System: Phase II", "uid": "p0000215", "west": -63.0}, {"awards": "0701232 Martinson, Douglas", "bounds_geometry": "POLYGON((-72 -64,-71.2 -64,-70.4 -64,-69.6 -64,-68.8 -64,-68 -64,-67.2 -64,-66.4 -64,-65.6 -64,-64.8 -64,-64 -64,-64 -64.4,-64 -64.8,-64 -65.2,-64 -65.6,-64 -66,-64 -66.4,-64 -66.8,-64 -67.2,-64 -67.6,-64 -68,-64.8 -68,-65.6 -68,-66.4 -68,-67.2 -68,-68 -68,-68.8 -68,-69.6 -68,-70.4 -68,-71.2 -68,-72 -68,-72 -67.6,-72 -67.2,-72 -66.8,-72 -66.4,-72 -66,-72 -65.6,-72 -65.2,-72 -64.8,-72 -64.4,-72 -64))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 03 Jun 2008 00:00:00 GMT", "description": "The Antarctic Peninsula (AP) is characterized by (1) the most rapid recent regional (winter) warming (5.35 times global mean), (2) a loss of nearly all its perennial sea ice cover on its western margin, and (3) 87% of the glaciers in retreat, contributing to global sea level rise. An ability to understand this change depends upon researchers\u0027 ability to better understand the underlying sources of this change and their driving mechanisms. Despite intensive efforts, the western AP (WAP) is chronically under-sampled. Therefore developing a capability to maintain a sustained in situ presence is a high scientific priority. The current proposal addresses this critical need through 2 objectives: (1) establish the feasibility of a Slocum Webb ocean glider to enable real-time high resolution data-adaptive polar oceanographic research; (2) address a critical question involving the regional climate change by measuring the ocean heat budget within a grid containing 14 years of ship-based ocean snapshots. This will involve the launch of the glider during the PAL-LTER austral summer research cruise, where it will fly the full along-shore distance of the LTER sample grid to be recovered at the southern extreme when the ship arrives there later in the summer. The glider will provide nearly continuous ocean property (temperature, salinity and pressure) coverage over this distance.\u003cbr/\u003e\u003cbr/\u003eIntellectual merit. The proposed activity will involve state of the art sampling methodology that will revolutionize the ability to address climate change and other scientific issues requiring sampling densities that could not be achieved by research vessels. Specifically, the adaptive sampling capability of the glider will be used to alter its course allowing identification of routes by which the source waters of the ocean heat (and nutrients) enter the continental shelf region, while the near-continuous sampling will provide a diagnosis of how well standard shipborne stations close the heat budget. Resources are adequate for this study due to heavy leveraging by the availability of the Rutgers SLOCUM Web glider, glider control center and participation of the team of experts that flew the first such glider.\u003cbr/\u003e\u003cbr/\u003eBroader Impacts. The proposed activity will advance discovery and understanding of the WAP responses to climate variability, to study the intricate feedback mechanisms associated with this variability and to better understand the chemical and physical processes associated with climate change. The data will be made available across the World Wide Web as it is collected, almost in real time, a potential bonanza for scientists during the upcoming International Polar Year, for classroom instruction and general outreach. Society will ultimately benefit from the improved knowledge of how climate change elsewhere in the world is impacting the unique ecosystem of the Antarctic, and driving glacial melt (sea level rise), among its other influences.", "east": -64.0, "geometry": "POINT(-68 -66)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e TEMPERATURE PROFILERS", "is_usap_dc": false, "keywords": "Pressure; Oceanography; AUVS; SLOCUM Web Glider; Salinity; Climate; Sampling", "locations": null, "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Martinson, Douglas; Kerfoot, John", "platforms": "WATER-BASED PLATFORMS \u003e UNCREWED VEHICLES \u003e SUBSURFACE \u003e AUVS", "repositories": null, "science_programs": null, "south": -68.0, "title": "Collaborative Research: Sloccum Glider in Western Antarctic Peninsula Continental Shelf Waters Pilot Study", "uid": "p0000734", "west": -72.0}, {"awards": "0229638 Ponganis, Paul", "bounds_geometry": "POLYGON((163 -77,163.4 -77,163.8 -77,164.2 -77,164.6 -77,165 -77,165.4 -77,165.8 -77,166.2 -77,166.6 -77,167 -77,167 -77.1,167 -77.2,167 -77.3,167 -77.4,167 -77.5,167 -77.6,167 -77.7,167 -77.8,167 -77.9,167 -78,166.6 -78,166.2 -78,165.8 -78,165.4 -78,165 -78,164.6 -78,164.2 -78,163.8 -78,163.4 -78,163 -78,163 -77.9,163 -77.8,163 -77.7,163 -77.6,163 -77.5,163 -77.4,163 -77.3,163 -77.2,163 -77.1,163 -77))", "dataset_titles": "Diving Physiology and Behavior of Emperor Penguins", "datasets": [{"dataset_uid": "600031", "doi": "10.15784/600031", "keywords": "Antarctica; Biota; Oceans; Penguin; Southern Ocean", "people": "Ponganis, Paul", "repository": "USAP-DC", "science_program": null, "title": "Diving Physiology and Behavior of Emperor Penguins", "url": "https://www.usap-dc.org/view/dataset/600031"}], "date_created": "Mon, 31 Mar 2008 00:00:00 GMT", "description": "The emperor penguin, Aptenodytes forsteri, is the premier avian diver and a top predator in the Antarctic ecosystem. The routine occurrence of 500-m diver during foraging trips to sea is both a physiological and behavior enigma. The objectives of this project address how and why emperors dive as deep and long as they do. The project examines four major topics in the diving biology of emperor penguins: pressure tolerance, oxygen store management, end-organ tolerance of diving hypoxemia/ischemia, and deep-dive foraging behavior. These subjects are relevant to the role of the emperor as a top predator in the Antarctic ecosystem, and to critical concepts in diving physiology, including decompression sickness, nitrogen narcosis, shallow water blackout, hypoxemic tolerance, and extension of aerobic dive time. The following hypotheses will be tested: 1) Prevention of nitrogen narcosis and decompression sickness in emperor penguins is achieved by inhibition of pulmonary gas exchange at depth. 2) Shallow water black out does not occur because of greater cerebral hypoxemic tolerance, and, in deep dives, because of resumption of pulmonary gas exchange during final ascent. 3) The rate of depletion of the blood oxygen store is a function of depth of dive and heart rate. 4) The aerobic dive limit (ADL) reflects the onset of lactate accumulation in locomotory muscle, not total depletion of all oxygen stores. 5) Elevation of tissue antioxidant capacity and free-radical scavenging enzyme activities protect against the routine ischemia/reperfusion which occur during diving. 6) During deep dives, the Antarctic silverfish, Pleuorogramma antarcticum, is the primary prey item for emperors. \u003cbr/\u003e\u003cbr/\u003eIn addition to evaluation of the hypotheses below, the project has broader impacts in several areas such as partnership with foreign and national institutes and organizations (e.g., the National Institute of Polar Research of Japan, Centro de Investigacioines del Noroeste of Mexico, National Geographic, the University of Texas Southwestern Medical Center, and Sea World). Participation in National Geographic television documentaries will provide unique educational opportunities for the general public; development of state-of-the-art technology (e.g., blood oxygen electrode recorders, blood samplers, and miniaturized digital cameras) will lay the groundwork for future research by this group and others; and the effects of the B15 iceberg on breeding success of emperor penguins will continue to be evaluated with population censuses during planned fieldwork at several Ross Sea emperor penguin colonies.", "east": 167.0, "geometry": "POINT(165 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ponganis, Paul", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Diving Physiology and Behavior of Emperor Penguins", "uid": "p0000239", "west": 163.0}, {"awards": "0232000 Cailliet, Gregor", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 10 Mar 2008 00:00:00 GMT", "description": "Recent years have seen the re-establishment of large-scale marine resource utilization by humans in the Antarctic. In contrast to early sealing and whaling activity, the modern impact is directed on krill and finfish populations, most notably of the Patagonian toothfish (Dissostichus eleginoides), but also its congenor the Antarctic toothfish (Dissostichus mawsoni) in the Ross Sea. Toothfish are a valuable resource and are likely to continue to command a high price in world markets. However, extensive illegal fishing has lead to considerable concern that Patagonian toothfish populations are being over-harvested. In other parts of the world, over-harvesting of larger, commercially valuable species has led to fishing down of marine food webs, leaving impoverished, less valuable ecosystems. The goal of the Convention for the Conservation of Antarctic Marine Living Resources, part of the Antarctic Treaty System, is to allow harvest while avoiding disruptions to the Antarctic ecosystem. To achieve this, the sustainable management of the fishery depends on reliable age data. Age data allow population age structure to be modeled, so that growth, mortality and recruitment rates can be estimated and used to understand population dynamics. Age data provides the basis to determine the life history pattern of a species, to model population dynamics, and to determine which age classes are vulnerable to over-exploitation under a particular set of environmental conditions. Current age and growth information for toothfish is based on age determination methodologies which are not validated and depend on the specific laboratory and principal investigator. Recently, the Commission of the Conservation of Antarctic Marine Living Resources has endorsed three preparation methodologies using otoliths and a common set of criteria for estimating age from otolith micro-structure. The CCAMLR Otolith Network has also been initiated as a medium for exchanging samples to ensure that age estimates are comparable between readers and laboratories. However, considerable work is needed to ensure that age estimates generated by the three methodologies are accurate. One technique that has been successful is radiometric age determination, which uses the disequilibria of lead-210 and radium-226 in otoliths as a natural chronometer. This proposal brings together an international collaboration to examine population age structure for both toothfish species, in an experimental design built around radiometric validation tests of age data generated by all three preparation methodologies. To integrate the validation component within an Antarctic-wide effort to examine toothfish population age structure, sub-samples for validation work will be drawn from sample sets taken for population age studies by research teams working in Australia, New Zealand, the United Kingdom and France, as well as the United States. Scientists at Moss Landing Marine Laboratories will use radiometric age determination to independently age otoliths from Patagonian and Antarctic toothfishes. Scientists at Old Dominion University will use a system already established for aging to generate validated age data, allowing growth, mortality, and longevity to be estimated by geographic areas. The project will provide validated otolith sample sets that can be used as a foundation for a unified and validated age estimation system for the toothfishes. This study will provide information which will be disseminated to the public, policy-makers and the international community. The project will provide opportunities for under-represented students at both universities.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ALPHA-SPECTROMETERS", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Andrews, Alan G.; ANDREWS, ALLEN", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Radiometric Age Validation of the Patagonian and Antarctic Toothfishes (Dissostichus Eleginoides and D. Mawsoni)", "uid": "p0000738", "west": null}, {"awards": "0537960 Beardsley, Robert", "bounds_geometry": "POLYGON((-110 -50,-104 -50,-98 -50,-92 -50,-86 -50,-80 -50,-74 -50,-68 -50,-62 -50,-56 -50,-50 -50,-50 -52.5,-50 -55,-50 -57.5,-50 -60,-50 -62.5,-50 -65,-50 -67.5,-50 -70,-50 -72.5,-50 -75,-56 -75,-62 -75,-68 -75,-74 -75,-80 -75,-86 -75,-92 -75,-98 -75,-104 -75,-110 -75,-110 -72.5,-110 -70,-110 -67.5,-110 -65,-110 -62.5,-110 -60,-110 -57.5,-110 -55,-110 -52.5,-110 -50))", "dataset_titles": "NODC Accession #0039274", "datasets": [{"dataset_uid": "001519", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "NODC Accession #0039274", "url": "http://www.nodc.noaa.gov/cgi-bin/search/prod/accessionsView.pl/details/0039274"}], "date_created": "Mon, 03 Mar 2008 00:00:00 GMT", "description": "Satellite-tracked drifters provide simple yet powerful tools to track the motion of near-surface water on time scales ranging from the tidal/inertial band to monthly and longer. The research described herein will deploy satellite-tracked surface drifters during the annual austral summer Palmer Long Term Ecological Research (LTER) cruises in January 2006 and 2007 in order to investigate the nearsurface Lagrangian currents over the western Antarctic Peninsula (wAP) shelf. This region is experiencing the highest surface air temperature increase (roughly +0.06 degrees C per year) in Antarctica, and LTER and other investigators have found that ecosystem responses to the rapid warming and sea ice decline are already apparent at all trophic levels from phytoplankton to penguins. Building a better understanding of the regional circulation and its variability seems an essential component to understand existing physical and biological processes and longer-term changes in this important and sensitive Antarctic ecosystem. These new Lagrangian measurements will complement those made during the 2001-2003 U.S. Southern Ocean (SO) GLOBEC program and provide the first detailed look at the near-surface flow in this important section of the wAP shelf. In particular, the combined 3-year LTER Lagrangian measurements should identify (a) the source region(s) of the buoyant coastal current discovered flowing southwest along the outer coast of Adelaide Island and into Marguerite Bay during SO GLOBEC and (b) if organized cross-shelf flows occur that help create a two gyre circulation over the shelf as suggested by Hofmann et al (1996) based on regional hydrography. The principal investigators will process and analyze the LTER 2005-2007 drifter data and collaborate with Palmer LTER investigators on the interpretation and integration of the Lagrangian data with their studies. The edited data, analysis results, and animations of the drifter data with surface weather data will be posted on the LTER website for use and viewing by scientists, students, and the public. Results will be presented at national meetings and published in referred journals.", "east": -50.0, "geometry": "POINT(-80 -62.5)", "instruments": null, "is_usap_dc": true, "keywords": null, "locations": null, "north": -50.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Beardsley, Robert; Limeburner, Richard", "platforms": null, "repo": "NCEI", "repositories": "NCEI", "science_programs": "LTER", "south": -75.0, "title": "Palmer LTER Lagrangian Current Measurements", "uid": "p0000232", "west": -110.0}, {"awards": "0230469 Wise, Sherwood", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 31 Jul 2007 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports the development of a standardized diatom image catalog or database. Diatoms are considered by many to be the most important microfossil group used today in the study of Antarctic Cenozoic marine deposits south of the Polar Front, from the near shore to deep sea. These microfossils, with walls of silica called frustules, are produced by single-celled plants (algae of the Class Bacillariophyceae) in a great variety of forms. Consequently, they have great biostratigraphic importance in the Southern Ocean and elsewhere for determining the age of marine sediments. Also, paleoclimatic and paleoceanographic studies increasingly rely on fossil diatom data. Changing biogeographic distributions of given taxa indicate shifting paleoecological conditions and provide evidence of the surface productivity and temperatures of ancient oceans. The generality of conclusions, though, is limited by variation in species concepts among workers. The broad research community relies, directly or indirectly, on the accurate identification of diatom species. Current technology can be used to greatly improve upon the standard references that have been used in making these identifications.\u003cbr/\u003e\u003cbr/\u003eThis project will develop an interactive digital-image catalog of modern and Cenozoic fossil diatoms of the Southern Ocean called \"DiatomWare\" for use by specialists and educators as an aid in rapid, accurate, and consistent species identification. As such, this will be a researcher\u0027s resource. It will be especially useful where it is not possible to maintain standard library resources such as onboard research vessels or at remote stations such as McMurdo Station. Major Antarctic geological drilling initiatives such as the new SHALDRIL project and the pending ANDRILL project will benefit from this product because they will rely heavily on diatom biostratigraphy to achieve their research objectives. The DiatomWare image database will be modeled on NannoWare, which was released in October 2002 on CD-ROM as a publication of the International Nannoplankton Association. BugCam will be adapted and modified as necessary to run the DiatomWare database, which can then be run from desktop or laptop computers. Images and text for the database will be scanned from the literature or captured in digital form from light or scanning electron microscopes.\u003cbr/\u003e\u003cbr/\u003eThe software interface will include a number of data fields that can be accessed by the click of a mouse button. Primary information will be the images and descriptions of the holotypes. In addition, representative images of paratypes or hypotypes will be included whenever possible in plain transmitted, differential interference contrast light and, when available, as drawings and SEM images. Also included will be a 35-word or less English diagnosis (\"mini-description\"), the biostratigraphic range in terms of zones and linear time, bibliographic references, lists of species considered junior synonyms, and similar species. The list of similar species will be cross-referenced with their respective image files to enable quick access for direct visual comparison on the viewing screen. Multiple images can be brought to the viewing screen simultaneously, and a zoom feature will permit image examination at a wide range of magnifications. Buttons will allow range charts, a bibliography, and key public-domain publications from the literature to be called up from within the program. The DiatomWare/BugCam package will be distributed at a nominal cost through a major nonprofit society via CD-ROM and free to Internet users on the Worldwide Web. Quality control measures will include critical review of the finalized database by a network of qualified specialists. The completed database will include descriptions and images of between 350 and 400 species, including fossil as well as modern forms that have no fossil record.\u003cbr/\u003e\u003cbr/\u003eThe development of the proposed diatom image database will be important to all research fields that depend on accurate biostratigraphic dating and paleoenvironmental interpretation of Antarctic marine sediments and plankton. The database will also serve as a valuable teaching tool for micropaleontology students and their professors, will provide a rapid means of keying down species for micropaleontologists of varying experience and background, and will promote a uniformity of taxonomic concepts since it will be developed and continuously updated with the advice of a community of nannofossil fossil experts. Broad use of the database is anticipated since it will be widely available through the Internet and on CD-ROM for use on personal computers that do not require large amounts of memory, costly specialized programs, or additional hardware.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Wise, Sherwood", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "DiatomWare: An Interactive Digital Image Catalog for Antarctic Cenozoic Diatoms", "uid": "p0000062", "west": null}, {"awards": "9909436 Farley, Kenneth", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 11 Jul 2007 00:00:00 GMT", "description": "9909436 \u003cbr/\u003eFarley\u003cbr/\u003e\u003cbr/\u003eThis award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an investigation of the uplift history of the Dry Valleys segment of the Transantarctic Mountains. The overall goal is to further constrain the exhumation history of the Transantarctic Mountains by using the newly developed apatite (U-Th)/He dating method on samples collected in vertical profiles. This approach, combined with existing apatite fission track information will constrain the rate and patterns of exhumation across the Transantarctic Mountains since their inception as a rift-flank uplift in the early Cenozoic.\u003cbr/\u003e\u003cbr/\u003eThis project will complement other projects and build on previous interpretations of the exhumation and tectonic history determined using apatite fission track thermochronology. It will bridge the gap between information on erosion rates determined from fission track thermochronology and from cosmogenic surface exposure dating and integrate the exhumation history of the mountains with their landscape evolution. As such, the results from this project will address an outstanding problem in Antarctic science; namely the stability of the East Antarctic Ice Sheet, and the timing of the transition from a \"warm\" dynamic ice sheet to a cold polar ice sheet. Highly relevant to this issue is the landscape evolution of the Transantarctic Mountains because many diverse lines of evidence for the rate of landscape evolution have been used to argue for a dynamic ice sheet up until either the Pliocene (the \"dynamic\" ice sheet model) or the middle Miocene (the \"stable\" ice sheet model). Understanding the past stability or dynamic fluctuations of the East Antarctic ice sheet with respect to the climate record is, of course, important for understanding how the present ice sheet may respond to global warming.\u003cbr/\u003e\u003cbr/\u003eThe specific objective of this project is to determine apatite (U-Th)/He age versus elevation trends for a number of vertical profiles from locations within the Transantarctic Mountain front and across the structural grain of the range. Fission track data already exist for all of these profiles, with apatite fission track ages ranging from 150-30 Ma. The greater precision of the (U-Th)/He technique and the fact it records information at lower temperatures (closure temperature of ~70 degrees Celsius; limits of 40-85 degrees Celsius for the He partial retention zone) will allow examination of the exhumation history of the TAM in more detail from ca 130 Ma to ~20 Ma. Another facet is to examine areas where Cretaceous exhumation is recorded and areas where the fission track profiles indicate periods of thermal and tectonic stability and minimal erosion throughout the Cretaceous. The variation of timing of the onset of more rapid exhumation accompanying uplift and formation of the Transantarctic Mountains in the early Cenozoic will also be examined.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Farley, Kenneth", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Exhumation of the Transantarctic Mountains: Constraints from (U-Th)/He Dating of Apatites", "uid": "p0000281", "west": null}, {"awards": "9615398 Encarnacion, John", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 11 Jul 2007 00:00:00 GMT", "description": "Encarnaci_n OPP 9615398 Abstract Basement rocks of the Transantarctic Mountains are believed to record a change in the paleo-Pacific margin of Gondwana from a rifted passive margin to a tectonically active margin (Ross orogen). Recent hypothesis suggest that the passive margin phase resulted from Neoproterozoic rifting of Laurentia from Antarctica (\"SWEAT\" hypothesis). The succeeding active margin phase (Ross orogeny) was one of several tectonic events (\"Pan African\" events) that resulted from plate convergence/transpression that was probably a consequence of the assembly of components of the Gondwana supercontinent. Although these basement units provide one of the keys for understanding the break up and assembly of these major continental masses, few precise ages are available to address the following important issues: (1) Is there any pre-rift high-grade cratonal basement exposed along the Transantarctic Mountains, and what is/are its precise age? Is this age compatible with a Laurentia connection? (2) What is the age of potential rift/passive margin sediments (Beardmore Group) along the Queen Maud Mountains sector of the orogen? (3) What is the relative and absolute timing of magmatism and contractional deformation of supracrustal units in the orogen? Was deformation diachronous and thus possibly related to transpressional tectonics, or did it occur in a discrete pulse that is more compatible with a collision? How does contraction of the orogen fit in with emplacement of voluminous plutonic and volcanic rocks? The answers to these questions are central to understanding the kinematic evolution of this major orogenic belt and its role in Neoproterozoic-Early Paleozoic continental reconstructions and plate kinematics. Hence, this award supports funding for precise U-Pb dating, using zircon, monazite, baddeleyite, and/or titanite from a variety of magmatic rocks in the Queen Ma ud Mountains, which can address the foregoing problems. In addition to the issues above, precise dating of volcanics that are interbedded with carbonates containing probable Middle Cambrian fauna could potentially provide a calibration point for the Middle Cambrian, which will fill a gap in the absolute time scale for the early Paleozoic.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Encarnacion, John", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Constraints on the Tectonomagmatic Evolution of the Pacific Margin of Gondwana from U-Pb Geochronology of Magmatic Rocks in the Transantarctic Basement", "uid": "p0000277", "west": null}, {"awards": "0233303 Jacobs, Stanley", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 09 Jul 2007 00:00:00 GMT", "description": "Major portions of the Antarctic Ice Sheet float in the surrounding ocean, at the physical and intellectual boundaries of oceanography and glaciology. These ice shelves lose mass continuously by melting into the sea, and periodically by the calving of icebergs. Those losses are compensated by the outflow of grounded ice, and by surface accumulation and basal freezing. Ice shelf sources and sinks vary on several time scales, but their wastage terms are not yet well known. Reports of substantial ice shelf retreat, regional ocean freshening and increased ice velocity and thinning are of particular concern at a time of warming ocean temperatures in waters that have access to deep glacier grounding lines.\u003cbr/\u003eThis award supports a study of the attrition of Antarctic ice shelves, using recent ocean geochemical measurements and drawing on numerical modeling and remote sensing resources. In cooperation with associates at Columbia University and the British Antarctic Survey, measurements of chlorofluorocarbon, helium, neon and oxygen isotopes will be used to infer basal melting beneath the Ross Ice Shelf, and a combination of oceanographic and altimeter data will be used to investigate the mass balance of George VI Ice Shelf. Ocean and remote sensing observations will also be used to help refine numerical models of ice cavity circulations. The objectives are to reduce uncertainties between different estimates of basal melting and freezing, evaluate regional variability, and provide an update of an earlier assessment of circumpolar net melting.\u003cbr/\u003eA better knowledge of ice shelf attrition is essential to an improved understanding of ice shelf response to climate change. Large ice shelf calving events can alter the ocean circulation and sea ice formation, and can lead to logistics problems such as those recently experienced in the Ross Sea. Broader impacts include the role of ice shelf meltwater in freshening and stabilizing the upper ocean, and in the formation of Antarctic Bottom Water, which can be traced far into the North Atlantic. To the extent that ice shelf attrition influences the flow of grounded ice, this work also has implications for ice sheet stability and sea level rise.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Ice Sheet; Basal Melting; Ice Shelf Meltwater; Not provided; Oceanography; Ice Velocity; Glaciology; Sea Level Rise; Ice Sheet Stability; Mass; Ross Ice Sheet; Numerical Model; Basal Freezing; Ice Cavity Circulations; George VI Ice Shelf; Outflow", "locations": "Ross Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Jacobs, Stanley", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Melting and Calving of Antarctic Ice Shelves", "uid": "p0000730", "west": null}, {"awards": "9725882 Raymond, Charles", "bounds_geometry": "POLYGON((-141.6722 -80.1678,-141.34195 -80.1678,-141.0117 -80.1678,-140.68145 -80.1678,-140.3512 -80.1678,-140.02095 -80.1678,-139.6907 -80.1678,-139.36045 -80.1678,-139.0302 -80.1678,-138.69995 -80.1678,-138.3697 -80.1678,-138.3697 -80.4863,-138.3697 -80.8048,-138.3697 -81.1233,-138.3697 -81.4418,-138.3697 -81.7603,-138.3697 -82.0788,-138.3697 -82.3973,-138.3697 -82.7158,-138.3697 -83.0343,-138.3697 -83.3528,-138.69995 -83.3528,-139.0302 -83.3528,-139.36045 -83.3528,-139.6907 -83.3528,-140.02095 -83.3528,-140.3512 -83.3528,-140.68145 -83.3528,-141.0117 -83.3528,-141.34195 -83.3528,-141.6722 -83.3528,-141.6722 -83.0343,-141.6722 -82.7158,-141.6722 -82.3973,-141.6722 -82.0788,-141.6722 -81.7603,-141.6722 -81.4418,-141.6722 -81.1233,-141.6722 -80.8048,-141.6722 -80.4863,-141.6722 -80.1678))", "dataset_titles": "Radar Investigations of Antarctic Ice Stream Margins, Siple Dome, 1998", "datasets": [{"dataset_uid": "609303", "doi": "10.7265/N52B8VZP", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Radar; Siple Dome", "people": "Nereson, Nadine A.; Raymond, Charles", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Radar Investigations of Antarctic Ice Stream Margins, Siple Dome, 1998", "url": "https://www.usap-dc.org/view/dataset/609303"}], "date_created": "Fri, 06 Jul 2007 00:00:00 GMT", "description": "9725882 Raymond This award is for support for a program of surface-based radio echo sounding to examine the geometry of the internal layering and the presence or absence of thawed zones outside the margins of active Ice Streams B and E and across the flow band feeding Ice Stream D. Melting in the marginal shear zone and/or on the bed outside an ice stream relates to the amount of support of the ice stream from the sides compared to the bed and the conditions that limit expansion of its width. Radar observations will be extended over the crest of adjacent inter-ice-stream ridges (B/C and D/E) and areas next to the flow band in the onset of D. The purpose is to examine internal layering indicative of the histories of these areas adjacent to ice streams and to determine whether ice streams have expanded into these presently stable areas in the past. These goals concerning the physical controls and history of ice stream width relate to how the discharge of ice streams has changed in the past and could change in the future to affect sea level.", "east": -138.3697, "geometry": "POINT(-140.02095 -81.7603)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS", "is_usap_dc": true, "keywords": "Ice Stream; Antarctica; Bed Geometry; GROUND-BASED OBSERVATIONS; Internal Layering; Internal Layer Geometry; Siple Dome; Shabtaie Ridge; Not provided; Engelhardt Ridge; Ice Stream Margins; Radar; Whillans Ice Stream; GPS; Bed Reflectivity; Macayeal Ice Stream; Surface Geometry", "locations": "Antarctica; Engelhardt Ridge; Macayeal Ice Stream; Shabtaie Ridge; Siple Dome; Whillans Ice Stream", "north": -80.1678, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Raymond, Charles; Nereson, Nadine A.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -83.3528, "title": "Internal Stratigraphy and Basal Conditions at the Margins ofActive Ice Streams of the Siple Coast, Antarctica", "uid": "p0000626", "west": -141.6722}, {"awards": "0229629 Anandakrishnan, Sridhar", "bounds_geometry": "POLYGON((-165 -82,-161.5 -82,-158 -82,-154.5 -82,-151 -82,-147.5 -82,-144 -82,-140.5 -82,-137 -82,-133.5 -82,-130 -82,-130 -82.2,-130 -82.4,-130 -82.6,-130 -82.8,-130 -83,-130 -83.2,-130 -83.4,-130 -83.6,-130 -83.8,-130 -84,-133.5 -84,-137 -84,-140.5 -84,-144 -84,-147.5 -84,-151 -84,-154.5 -84,-158 -84,-161.5 -84,-165 -84,-165 -83.8,-165 -83.6,-165 -83.4,-165 -83.2,-165 -83,-165 -82.8,-165 -82.6,-165 -82.4,-165 -82.2,-165 -82))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 14 Jun 2007 00:00:00 GMT", "description": "This award supports a project to investigate the new-found, startling sensitivity of two major West Antarctic ice streams to tidal oscillations to learn the extent and character of the effect and its ramifications for future ice-stream behavior. Ice streams D, C and Whillans (B) all show strong but distinct tidal signals. The ice plain of Whillans is usually stopped outright, forward motion being limited to two brief periods each day, at high tide and on the falling tide. Motion events propagate across the ice plain at seismic wave velocities. Near the mouth of D, tides cause a diurnal variation of about 50% in ice-stream speed that propagates upglacier more slowly than on Whillans, and seismic data show that C experiences even slower upglacier propagation of tidal signals. Tidal influences are observed more than 100 km upglacier on C, more than 40 km upglacier on D, and may be responsible for fluctuations in basal water pressure reported 400 km upstream on Whillans, nearly the full length of the ice stream. During the first year, the spatial extent of this behavior will be measured on Whillans Ice Stream and ice stream D by five coordinated seismic and GPS instrument packages at 100-km spacing on each ice stream. These packages will be deployed by Twin Otter at sites selected by review of satellite imagery and will operate autonomously through a combination of solar and battery power for two lunar cycles to study the sensitivity of the ice stream motion to spring and neap tides. Additionally, existing data sets will be examined further for clues to the mechanisms involved, and preliminary models will be developed to reconcile the seemingly contrasting behaviors observed on the ice streams. The second and third field seasons will examine in greater detail the tidal behavior of Whillans (year 2) and D (year 3). Work will especially focus on detailed study of at least one source area for events on Whillans, assuming that source areas inferred from preliminary data remain active. Vertical motions have not yet been detected, but differential GPS will increase our detection sensitivity. Seismic instrumentation will greatly increase temporal resolution and the ability to measure the propagation speed and any spatial heterogeneity. Modeling will be refined as more is learned from the field experiments. The project should yield numerous broader impacts. The improved knowledge of ice-stream behavior from this study will contribute to assessment of the potential for rapid ice-sheet change affecting global sea level with societal consequences. Results will be disseminated through scientific publication and talks at professional meetings, as well as contacts with the press, university classes taught by the PIs, visits to schools and community groups, and other activities. Two graduate students will be educated through the project.", "east": -130.0, "geometry": "POINT(-147.5 -83)", "instruments": null, "is_usap_dc": false, "keywords": "Ice Stream; Tidal Motion; Vertical Motions; Seismic; West Antarctic; Ice Stream Motion; Global Sea Level; Modeling; Not provided", "locations": "West Antarctic", "north": -82.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Anandakrishnan, Sridhar; Alley, Richard; Voigt, Donald E.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -84.0, "title": "Collaborative Research: Tidal Modulation of Ice Stream Flow", "uid": "p0000075", "west": -165.0}, {"awards": "0229490 Conway, Howard", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 30 Apr 2007 00:00:00 GMT", "description": "This award supports a project to improve understanding of post-glacial retreat and thinning of the Siple Coast region. Research has shown how age-depth relationships from ice cores can be extrapolated over wide areas by tracking continuous radar layers. By comparing radar-derived timescales with one from a model of ice- flow, glacial conditions over regional scales were inferred. High-resolution radar profiles have been collected across most of the inter-stream ridges in the Siple Coast region, and an age- depth relationship has been established from the Siple Dome ice core. Application of the techniques used by others is problematic because the ice streams that surround Siple Dome have disrupted the continuity of the internal layers. A specific goal of this project is to search for other less direct ways to match radar layers between unconnected profiles. The correspondence between radar reflections and measurements of electrical conductivity and volcanic sulfates along the Siple Dome core will be investigated. The strategy is to search for distinctive patterns in the echoes that will facilitate layer matching. Preliminary results are encouraging: at least four distinct echoes at Siple Dome can be matched to spikes in the conductivity profile and the signature of one (at 210m depth, which is ~1,800 yrs BP) closely resembles that of a layer at ~200m on Ridge BC. Matching layers (and hence timescales) across the ice streams will allow reconstruction of spatial patterns of past flow, thinning and accumulation rate in the Siple Coast region, which is needed to predict future possible changes of the West Antarctic Ice Sheet. Data necessary for the proposed work are already available; additional fieldwork in Antarctica is not required. The project will take two years to complete and will provide core education for a doctoral student in Earth and Space Sciences, with an emphasis on radioglaciology.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard; Sylvester, John; Winebrenner, Dale", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Investigation of the Glacial History of the Siple Coast Using Radar-Detected Internal Layers and the Ice Core from Siple Dome", "uid": "p0000723", "west": null}, {"awards": "0337838 Fricker, Helen", "bounds_geometry": "POINT(71 -69.75)", "dataset_titles": "Access to data", "datasets": [{"dataset_uid": "001537", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Access to data", "url": "http://www.iris.edu/data/data.htm"}], "date_created": "Fri, 27 Apr 2007 00:00:00 GMT", "description": "This award supports a comprehensive study of rift growth on the Amery Ice Shelf (AIS), East Antarctica, using a combination of in situ and remote sensing data with numerical modeling. On the AIS there is an opportunity to examine an active rift system, which is a combination of two longitudinal-to-flow rifts, which originated at the ice shelf front in the suture zones between merging flowbands, and two transverse-to-flow rifts, which formed at the tip of the western longitudinal rift around 1996. Work in progress indicates that these two transverse rifts do not propagate independently of each other, but somehow grow more or less synchronously. The longest of these rifts-the eastern one-grows at an average rate of about 8m per day. When it meets the eastern longitudinal rift, an event that is expected to occur during the funding period (mid-2006), an iceberg (~30 x 30 km) will calve. Based on observations collected over the past half century, there is reason to believe that such a calving event may be a part of a repetitive sequence. In the proposed project, the expansion and propagation of both transverse rifts will be studied using a network of GPS and seismometers deployed around the tip of each transverse rift. Once the iceberg has calved, the effects its calving has on the dynamics of the ice shelf and the activation of previously inactive rifts will also be studied. Insofar as the rate of calving activity is a proxy for local and regional climate conditions, a broader impact of the proposed work is directly related to the socio-environmental topics of climate and sea-level change. The subject of iceberg calving has a history of sparking a great deal of interest from the media and the public alike, especially since the recent large calving events from the Ross and Ronne ice shelves and the remarkably sudden break-up of the Larsen Ice Shelf. The work will involve at least one graduate student, and will involve a partnership with a local charter high school. Field work, instrument deployments, and data collection and analysis will be conducted in close collaboration with the Australian Antarctic Division and the University of Tasmania, which has been a crucial component of research conducted to date. This project will also make use of the Scripps Institution of Oceanography Visualization Center as a means to display results to faculty and researchers of the University of California, San Diego, undergraduate and graduate students, to school children and their teachers, and ultimately to the visiting public.", "east": 71.0, "geometry": "POINT(71 -69.75)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS", "is_usap_dc": false, "keywords": "Not provided; Geodesy; Seismic", "locations": null, "north": -69.75, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fricker, Helen; Minster, Jean-Bernard", "platforms": "Not provided", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -69.75, "title": "Monitoring an Active Rift System at the Front of Amery Ice Shelf, East Antarctica", "uid": "p0000668", "west": 71.0}, {"awards": "0538475 Bart, Philip", "bounds_geometry": "POLYGON((-180 -75,-178 -75,-176 -75,-174 -75,-172 -75,-170 -75,-168 -75,-166 -75,-164 -75,-162 -75,-160 -75,-160 -75.3,-160 -75.6,-160 -75.9,-160 -76.2,-160 -76.5,-160 -76.8,-160 -77.1,-160 -77.4,-160 -77.7,-160 -78,-162 -78,-164 -78,-166 -78,-168 -78,-170 -78,-172 -78,-174 -78,-176 -78,-178 -78,-180 -78,-180 -77.7,-180 -77.4,-180 -77.1,-180 -76.8,-180 -76.5,-180 -76.2,-180 -75.9,-180 -75.6,-180 -75.3,-180 -75))", "dataset_titles": "NBP0802 and NBP0803 Sediment samples (full data link not provided); NBP0802 data; NBP0803 data", "datasets": [{"dataset_uid": "000123", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0803 data", "url": "https://www.rvdata.us/search/cruise/NBP0803"}, {"dataset_uid": "000122", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0802 data", "url": "https://www.rvdata.us/search/cruise/NBP0802"}, {"dataset_uid": "000138", "doi": "", "keywords": null, "people": null, "repository": "AMGRF", "science_program": null, "title": "NBP0802 and NBP0803 Sediment samples (full data link not provided)", "url": "http://www.arf.fsu.edu/"}], "date_created": "Thu, 29 Mar 2007 00:00:00 GMT", "description": "This project determines the recent history of the West Antarctic Ice Sheet (WAIS) through a multidisciplinary study of the seabed in the Ross Sea of Antarctica. WAIS is perhaps the world\u0027s most critical ice sheet to sea level rise dut to near-future global warming. its history has been a key focus for the past decade, but there are significant questions as to whether WAIS was stable during the last glacial maximum--about 20,000 years ago--or undergoing advance and retreat. This project studies grounding zone translantions in Eastern Basin to constrain WAIS movements using a multidisciplinary approach that integrates multibeam bathymetry, seismic stratigraphy, sedimentology, diatom biostratigraphy, radiocarbon dating, 10Be concentration analyses, and numerical modeling.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts include improving society\u0027s understanding of sea level rise linked to global warming; postdoctoral, graduate, and undergraduate education; and expanding the participation of groups underrepresented in Earth sciences through links with LSU\u0027s Geoscience Alliance to Encourage Minority Participation.", "east": -160.0, "geometry": "POINT(-170 -76.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e SEISMIC REFLECTION PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e WATERGUNS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES", "is_usap_dc": true, "keywords": "Ross Sea; R/V NBP; Ice Sheet; Last Glacial Maximum; Seismic Stratigraphy", "locations": "Ross Sea", "north": -75.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Bart, Philip; Tomkin, Jonathan", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "AMGRF; R2R", "science_programs": null, "south": -78.0, "title": "WAIS grounding-zone migrations in Eastern Basin, Ross Sea and the LGM dilemma: New strategies to resolve the style and timing of outer continental shelf grounding events", "uid": "p0000539", "west": -180.0}, {"awards": "0003844 Case, Judd", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG0309", "datasets": [{"dataset_uid": "002676", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0309", "url": "https://www.rvdata.us/search/cruise/LMG0309"}, {"dataset_uid": "001683", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0309"}], "date_created": "Wed, 28 Mar 2007 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a collaborative research project between the Saint Mary\u0027s College of California, the South Dakota School of Mines and technology, and the Argentine Antarctic Institute (Instituto Antartico Argentino or IAA) to investigate the Late Mesozoic vertebrate paleontology of the James Ross Basin in the Antarctic Peninsula region. The Campanian through the Maastrichtian ages (80 to 65 million years ago) is an important time interval concerning vertebrate biogeography (i.e. dispersals and separations due to moving landmasses) and evolution between Antarctica and other Southern Hemisphere continents (including India, i.e. Gondwana). Moreover, the dispersal of terrestrial vertebrates (i.e. dinosaurs and marsupial mammals) from North America to Antarctica and beyond (e.g. Australia) via Patagonia and the Antarctic Peninsula, as well as the dispersal of modern birds from Antarctica northward are important unresolved questions in paleontology. These dispersal events include vertebrates not only in the terrestrial realms, but also in marine settings. Both widely distributed and localized marine reptile species have been identified in Antarctica, creating questions concerning their dispersal in conjunction with the terrestrial animals.\u003cbr/\u003e\u003cbr/\u003eThe Antarctic Peninsula and Patagonia represent the western-most portion of the Weddellian Paleobiogeographic Province, a region that extends from Patagonia through the Antarctic Peninsula and western Antarctica to Australia and New Zealand. Within this province lie the dispersal routes for interchanges of vertebrates between South America and: 1) Madagascar and India, and 2) Australia. As the result of previous work by the principal investigators, it is postulated that an isthmus between more northern South America and the Antarctic craton has served to bring typical North American dinosaurs, such as hadrosaurs (duck-billed dinosaurs) and presumably marsupials traveling overland, while marine reptiles swam along coastal waters, to Antarctica in the latest Cretaceous. Finally, this region has served as the cradle for the evolution, if not the origin, for groups of modern birds, and evolution of a suite of typical southern hemisphere plants.\u003cbr/\u003e\u003cbr/\u003eIn order to confirm and expand upon these hypotheses, investigations into the latest Cretaceous deposits of the James Ross Basin, Antarctica Peninsula must be continued. The Cape Lamb and Sandwich Bluff geological units, of the Lopez de Bertodano Formation in the James Ross Basin along the eastern Antarctic Peninsula, exhibit a mixture of marine and terrestrial deposits. The following vertebrates have been recovered from these sedimentary deposits during previous field seasons: plesiosaur and mosasaur marine reptiles; plant eating dinosaurs; a meat eating dinosaur; and a variety of modern bird groups, including shorebirds, wading birds and lagoonal birds.\u003cbr/\u003e\u003cbr/\u003eThis project will undertake new fieldwork to recover new specimens in order to test biogeographic and evolutionary hypotheses concerning Late Cretaceous vertebrates in Gondwana. Fieldwork is planned in January 2002 and 2003 to explore the eastern slopes of Cape Lamb, Sandwich Bluff and False Island Point on Vega Island, and the Santa Marta Cove area of James Ross Island.\u003cbr/\u003e\u003cbr/\u003eThis research will result in important new insights about the evolution and geographic dispersal of several vertebrate species. The results are important to understanding the development and evolution of life on Earth.\u003cbr/\u003e\u003cbr/\u003eThis is a collaborative research project with Argentinean scientists from the IAA and it continues a productive collaboration that began in 1995. In addition, collaboration with vertebrate paleontologists from the Museo de La Plata, both in the field and at our respective institutions in Argentina and in the United States, will continue.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "Not provided; R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e MESOZOIC \u003e CRETACEOUS", "persons": "Case, Judd; Blake, Daniel", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Evolution and Biogeography of Late Cretaceous Vertebrates from the James Ross Basin, Antarctic Peninsula", "uid": "p0000129", "west": null}, {"awards": "0229292 Cressie, Noel", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 28 Feb 2007 00:00:00 GMT", "description": "Ice streams are believed to play a major role in determining the response of their parent ice sheet to climate change, and in determining global sea level by serving as regulators on the fresh water stored in the ice sheets. Ice streams are characterized by rapid, laterally confined flow which makes them uniquely identifiable within the body of the more slowly and more homogeneously flowing ice sheet. But while these characteristics enable the identification of ice streams, the processes which control ice-stream motion and evolution, and differences among ice streams in the polar regions, are only partially understood. Understanding the relative importance of lateral and basal drags, as well as the role of gradients in longitudinal stress, is essential for developing models for future evolution of the polar ice\u003cbr/\u003esheets. In this project, physical statistical models will be used to explore the processes that control ice-stream flow, and to compare these processes between seemingly different ice-stream systems. In particular, Whillans Ice Stream draining into the Ross Ice Shelf, will be compared with Recovery and RAMP glaciers draining into the Ronne-Filchner Ice Shelf, and the Northeast Ice Stream in Greenland. Geophysical models lie at the core of the approach, but are embellished by modeling various components of variability statistically. One important component comes from the uncertainty in observations on basal elevation, surface elevation, and surface velocity. In this project new observational data collected using remote-sensing techniques will be used. The various components, some of which are spatial, are combined hierarchically using Bayesian statistical methodology. All these components will be combined mathematically into a physical statistical model that yields the posterior distribution for basal, longitudinal, and lateral stress fields, and velocity fields, conditional on the data. Inference based on this distribution will be carried out via Markov chain Monte Carlo techniques, to obtain estimates of these unknown fields along with uncertainty measures associated with them.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Surface Elevation; Stress Field; Basal Elevation; DHC-6", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Cressie, Noel; Jezek, Kenneth; Berliner, L.", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e DHC-6", "repositories": null, "science_programs": null, "south": null, "title": "Dynamics of Ice Streams: A Physical Statistical Approach", "uid": "p0000711", "west": null}, {"awards": "9814816 Blankenship, Donald", "bounds_geometry": "POLYGON((-129 -80.5,-128.4 -80.5,-127.8 -80.5,-127.2 -80.5,-126.6 -80.5,-126 -80.5,-125.4 -80.5,-124.8 -80.5,-124.2 -80.5,-123.6 -80.5,-123 -80.5,-123 -80.55,-123 -80.6,-123 -80.65,-123 -80.7,-123 -80.75,-123 -80.8,-123 -80.85,-123 -80.9,-123 -80.95,-123 -81,-123.6 -81,-124.2 -81,-124.8 -81,-125.4 -81,-126 -81,-126.6 -81,-127.2 -81,-127.8 -81,-128.4 -81,-129 -81,-129 -80.95,-129 -80.9,-129 -80.85,-129 -80.8,-129 -80.75,-129 -80.7,-129 -80.65,-129 -80.6,-129 -80.55,-129 -80.5))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 13 Feb 2007 00:00:00 GMT", "description": "9814816\u003cbr/\u003eBlankenship\u003cbr/\u003e\u003cbr/\u003eThis award supports a four year project to develop of better understanding the ice streams of the Ross Sea Embayment (A--F) which drain the interior West Antarctic Ice Sheet (WAIS) by rapidly moving vast quantities of ice to the calving front of the Ross Ice Shelf. The project will examine the role of these ice streams as buffers between the interior ice and the floating ice shelves. The reasons for their fast flow, the factors controlling their current grounding-line-, margin-, and head-positions are crucial to any attempt at modeling the WAIS system and predicting the future of the ice sheet. For the Antarctic ice streams of the Siple Coast, the transition from no-sliding (or all internal deformation) to motion dominated by sliding is defined as the \"onset-region\". To fully understand (and adequately model) the WAIS, this onset region must be better understood. The lateral margins of the ice streams are also a transition that need better explanation. Hypotheses on controls of the location of the onset region range from the \"purely-glaciologic\" to the \"purely-geologic. Thus, to model the ice sheet accurately, the basal boundary conditions (roughness, wetness, till properties) and a good subglacial geologic map, showing the distribution, thickness, and properties of the sedimentary basins, are required. These parameters can be estimated from seismic, radar, and other geophysical methods. The transition region of ice stream D will be studied in detail with this coupled geophysical experiment. In addition, selected other locations on ice streams C \u0026 D will be made, to compare and contrast conditions with the main site on ice stream D. Site-selection for the main camp will be based on existing radar, GPS, and satellite data as well as input from the modeling community.", "east": -123.0, "geometry": "POINT(-126 -80.75)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -80.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Blankenship, Donald D.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -81.0, "title": "Collaborative Research: Characterizing the Onset of Ice Stream Flow: A Ground Geophysical Field Program", "uid": "p0000603", "west": -129.0}, {"awards": "0125579 Cuffey, Kurt; 0126202 Blankenship, Donald", "bounds_geometry": "POLYGON((160 -77.6,160.25 -77.6,160.5 -77.6,160.75 -77.6,161 -77.6,161.25 -77.6,161.5 -77.6,161.75 -77.6,162 -77.6,162.25 -77.6,162.5 -77.6,162.5 -77.63,162.5 -77.66,162.5 -77.69,162.5 -77.72,162.5 -77.75,162.5 -77.78,162.5 -77.81,162.5 -77.84,162.5 -77.87,162.5 -77.9,162.25 -77.9,162 -77.9,161.75 -77.9,161.5 -77.9,161.25 -77.9,161 -77.9,160.75 -77.9,160.5 -77.9,160.25 -77.9,160 -77.9,160 -77.87,160 -77.84,160 -77.81,160 -77.78,160 -77.75,160 -77.72,160 -77.69,160 -77.66,160 -77.63,160 -77.6))", "dataset_titles": "Ablation Rates of Taylor Glacier, Antarctica; Stable Isotopes of Ice on the Surface of Taylor Glacier, Antarctica; Surface Velocities of Taylor Glacier, Antarctica", "datasets": [{"dataset_uid": "609326", "doi": "10.7265/N5N29TW8", "keywords": "Ablation Poles; Ablation Rates; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Taylor Glacier", "people": "Cuffey, Kurt M.; Bliss, Andrew; Kavanaugh, Jeffrey", "repository": "USAP-DC", "science_program": null, "title": "Ablation Rates of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609326"}, {"dataset_uid": "609324", "doi": "10.7265/N5RV0KM7", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Velocity; Taylor Glacier", "people": "Kavanaugh, Jeffrey; Aciego, Sarah; Bliss, Andrew; Cuffey, Kurt M.", "repository": "USAP-DC", "science_program": null, "title": "Surface Velocities of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609324"}, {"dataset_uid": "609323", "doi": "10.7265/N5WM1BBZ", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Isotope; Taylor Glacier", "people": "Bliss, Andrew; Cuffey, Kurt M.; Kavanaugh, Jeffrey; Aciego, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Stable Isotopes of Ice on the Surface of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609323"}], "date_created": "Tue, 13 Feb 2007 00:00:00 GMT", "description": "This award supports a project to significantly improve our understanding of how Taylor Glacier flows and responds to climate changes. Taylor Glacier drains the Taylor Dome region of the East Antarctic Ice Sheet and terminates in Taylor Valley, one of the Dry Valleys of Victoria Land. It provides a crucial and unique link between two intensively studied Antarctic environments: the Taylor Dome, from which a 130 kyr ice core paleoclimate record has recently been extracted, and the Dry Valleys, a pivotal Long-Term Ecological Research (LTER) site and a focus of research on geomorphology and glacial geology. The proposed work will thus make an important contribution to ongoing efforts to exploit the Taylor Dome - Dry Valleys system to build a uniquely comprehensive view of regional long-term environmental changes. The proposed work has two complementary components: field research and numerical modelling. Two field seasons will be used to measure velocity, surface strain rate, mass balance, ice thickness, glacier bed reflectance, and subglacial topography, along a nearly complete longitudinal transect of the Taylor Glacier, and along select cross-valley transects. This information will be used to constrain numerical models of ice and heat flow for the Taylor Dome - Taylor Glacier system. These calibrated models will be used to analyze the time-dependent response of the Taylor Glacier to climate changes. The synthesis of results will be aimed to improve understanding of the glacial geomorphology of Taylor Valley, and to illuminate impacts on the Taylor Valley lakes ecosystem. The project will have a major role in furthering the careers of a doctoral-level graduate student and a post-doctoral researcher.", "east": 162.5, "geometry": "POINT(161.25 -77.75)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Glacier; Glacier Surface; Glacier Surface Ablation; Ice Velocity; Velocity Measurements; Taylor Glacier; Isotope; GPS; Ice Sheet Elevation; Not provided; FIELD INVESTIGATION; Ice Surface Elevation; Ablation; Oxygen Isotope; Elevation; Deuterium; GROUND-BASED OBSERVATIONS; Glacier Surface Ablation Rate; Surface Elevation", "locations": "Taylor Glacier", "north": -77.6, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Bliss, Andrew; Kavanaugh, Jeffrey; Aciego, Sarah; Cuffey, Kurt M.; Morse, David L.; Blankenship, Donald D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.9, "title": "Collaborative Research: Dynamics and Climatic Response of the Taylor Glacier System", "uid": "p0000084", "west": 160.0}, {"awards": "0126270 Doran, Peter", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 05 Feb 2007 00:00:00 GMT", "description": "Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Doran, Peter", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Paleoclimate Inferred from Lake Sediment Cores in Taylor Valley, Antarctica", "uid": "p0000092", "west": null}, {"awards": "0229917 Becker, Luann", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 24 Jan 2007 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an interdisciplinary study of fluvial sediments in Antarctica for evidence of what caused the greatest of all mass extinctions in the history of life at the Permian-Triassic boundary. This boundary was, until recently, difficult to locate and thought to be unequivocally disconformable in Antarctica. New studies, particularly of carbon isotopic chemostratigraphy and of paleosols and root traces as paleoecosystem indicators, together with improved fossil plant, reptile and pollen biostratigraphy, now suggest that the precise location of the boundary might be identified and have led to local discovery of iridium anomalies, shocked quartz, and fullerenes with extraterrestrial noble gases. These anomalies are associated with a distinctive claystone breccia bed, similar to strata known in South Africa and Australia, and taken as evidence of deforestation. There is already much evidence from Antarctica and elsewhere that the mass extinction on land was abrupt and synchronous with extinction in the ocean. The problem now is what led to such death and destruction. Carbon isotopic values are so low in these and other Permian-Triassic boundary sections that there was likely to have been some role for catastrophic destabilization of methane clathrates. Getting the modeled amount of methane out of likely reservoirs would require such catastrophic events as bolide impact, flood-basalt eruption or continental-shelf collapse, which have all independently been implicated in the mass extinction and for which there is independent evidence. Teasing apart these various hypotheses requires careful re-examination of beds that appear to represent the Permian-Triassic boundary, and search for more informative sequences, as was the case for the Cretaceous-Tertiary boundary. This collaborative research on geochemistry and petrography of boundary beds and paleosols (by Retallack), on carbon isotopic variation through the boundary interval (by Jahren), and on fullerenes, iridium and helium (by Becker) is designed to test these ideas about the Permian-Triassic boundary in Antarctica and to shed light on processes which contributed to this largest of mass extinctions on Earth. Fieldwork for this research will be conducted in the central Transantarctic Mountains and in Southern Victoria Land with an initial objective of examining the stratigraphic sequences for continuity across the boundary. Stratigraphic continuity is a critical element that must exist for the work to be successful. If fieldwork indicates sufficiently continuous sections, the full analytical program will follow fieldwork.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e PROBES; SOLAR/SPACE OBSERVING INSTRUMENTS \u003e PARTICLE DETECTORS \u003e SEM", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Becker, Luann", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Permian-Triassic Mass Extinction in Antarctica", "uid": "p0000718", "west": null}, {"awards": "0230348 Dunbar, Nelia; 0230021 Sowers, Todd; 0230316 White, James", "bounds_geometry": "POINT(135.1333 -76.05)", "dataset_titles": "Mount Moulton Isotopes and Other Ice Core Data", "datasets": [{"dataset_uid": "609640", "doi": "10.7265/N5FT8J0N", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Epica Dome C; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Lake Vostok; Mount Moulton; Paleoclimate; Talos Dome; Taylor Dome", "people": "Steig, Eric J.; Popp, Trevor; White, James", "repository": "USAP-DC", "science_program": null, "title": "Mount Moulton Isotopes and Other Ice Core Data", "url": "https://www.usap-dc.org/view/dataset/609640"}], "date_created": "Tue, 01 Aug 2006 00:00:00 GMT", "description": "The summit crater of Mt. Moulton, in West Antarctica, contains a 600-m thick horizontally-exposed section of ice with intercalated tephra layers from nearby Mt Berlin. Argon-40/Argon-39 dating of the thick, near-source tephra indicates that the age of the horizontal ice section ranges between 15,000 and 492,000 years. Thus, the Mt Moulton site offers an unparalleled repository of ancient West Antarctic snow and trapped air that can be used to investigate West Antarctic climate over much of the past 500,000 years. The planar nature and consistent dips of the tephra layers suggests that, although the ice section has thinned, it is otherwise undeformed. The Mt. Moulton site was visited during the 1999/2000 field season, at which time a horizontal ice core representing approximately 400 meters of ice was collected, ranging in age from 15,000 to older than 480,000 years. In addition to this horizontal core, samples of ice at a range of depths were collected in order to test the quality of the climate record in the ice. Forty tephra layers intercalated in the ice were also collected in order to provide chronology for the ice section. The results of this first effort are extremely encouraging. Based on the d?18 O of ice, for example, there is clearly a useable record of past climate at Mt. Moulton extending back beyond 140,000 years. There is work to do, however, to realize the full potential of this horizontal ice core. The elemental and isotopic composition of trapped gases suggest some contamination with modern air, for example. As gas cross-dating of ice cores is the current standard by which climate records are intercompared, we need to understand why and how the gas record is compromised before adding Moulton to our arsenal of ice core paleoclimate records. This award supports a collaborative effort between three institutions with following objectives: 1) to evaluate more thoroughly the integrity of the climatic record through shallow drilling of the blue ice area, as well as the snow field upslope from the blue ice; 2) to improve the radioisotopic dating of specific tephra layers; 3) to obtain baseline information about modern snowfall deposition, mean annual temperature, and wind pumping around the summit of Mt. Moulton; and 4) to study how firn densification differs when surface accumulation changes from net accumulation to net ablation.", "east": 135.1333, "geometry": "POINT(135.1333 -76.05)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e ELECTRON MICROPROBES", "is_usap_dc": true, "keywords": "LABORATORY; Climate; Argon-40; 40Ar; Argon-39; FIELD SURVEYS; Chronology; Ice Core Gas Age; Gas Record; Ice Core; FIELD INVESTIGATION; Tephra; Mount Moulton; Not provided; Caldera; 39Ar; Stratigraphy; Ice Core Depth", "locations": "Mount Moulton", "north": -76.05, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "White, James; Popp, Trevor; Dunbar, Nelia; Sowers, Todd A.; Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.05, "title": "Collaborative Research: Refining a 500-kry Climate Record From the Moulton Blue Ice Field in West Antarctica", "uid": "p0000755", "west": 135.1333}, {"awards": "0125276 Albert, Mary; 0125570 Scambos, Ted", "bounds_geometry": null, "dataset_titles": "Access AGDC data online by navigating to Data Sets. Data sets are arranged by Principal Investigators. Access data that are combined into multiple data sets, or compiled products.; AWS Data: Characteristics of Snow Megadunes and Their Potential Effect on Ice Core Interpretation; GPR and GPS Data: Characteristics of Snow Megadunes and their Potential Effects on Ice Core Interpretation; Snow and Firn Permeability: Characteristics of Snow Megadunes and their Potential Effects on Ice Core Interpretation; The Antarctic Glaciological Data Center (AGDC) at the National Snow and Ice Data Center (NSIDC) archives and distributes Antarctic glaciological and cryospheric system data collected by the U.S. Antarctic Program.", "datasets": [{"dataset_uid": "609283", "doi": "10.7265/N5K935F3", "keywords": "Antarctica; Atmosphere; East Antarctic Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Meteorology; Snow/ice; Snow/Ice", "people": "Scambos, Ted; Bauer, Rob; Haran, Terry; Fahnestock, Mark", "repository": "USAP-DC", "science_program": null, "title": "AWS Data: Characteristics of Snow Megadunes and Their Potential Effect on Ice Core Interpretation", "url": "https://www.usap-dc.org/view/dataset/609283"}, {"dataset_uid": "001669", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "Access AGDC data online by navigating to Data Sets. Data sets are arranged by Principal Investigators. Access data that are combined into multiple data sets, or compiled products.", "url": "http://nsidc.org/data/agdc_investigators.html"}, {"dataset_uid": "001343", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "The Antarctic Glaciological Data Center (AGDC) at the National Snow and Ice Data Center (NSIDC) archives and distributes Antarctic glaciological and cryospheric system data collected by the U.S. Antarctic Program.", "url": "https://nsidc.org/data/agdc/"}, {"dataset_uid": "609282", "doi": "10.7265/N5Q23X5F", "keywords": "Antarctica; East Antarctic Plateau; Glaciology; GPR; GPS; Navigation; Paleoclimate; Snow/ice; Snow/Ice", "people": "Scambos, Ted; Bauer, Rob", "repository": "USAP-DC", "science_program": null, "title": "GPR and GPS Data: Characteristics of Snow Megadunes and their Potential Effects on Ice Core Interpretation", "url": "https://www.usap-dc.org/view/dataset/609282"}, {"dataset_uid": "609299", "doi": "10.7265/N5639MPD", "keywords": "Antarctica; East Antarctic Plateau; Glaciology; Physical Properties; Snow/ice; Snow/Ice", "people": "Cathles, Mac; Albert, Mary R.; Courville, Zoe", "repository": "USAP-DC", "science_program": null, "title": "Snow and Firn Permeability: Characteristics of Snow Megadunes and their Potential Effects on Ice Core Interpretation", "url": "https://www.usap-dc.org/view/dataset/609299"}], "date_created": "Wed, 04 Jan 2006 00:00:00 GMT", "description": "This award supports a program of field surveys of an area within the large, well-developed megadune field southeast of Vostok station. The objectives are to determine the physical characteristics of the firn across the dunes, including typical climate indicators such as stable isotopes and major chemical species, and to install instruments to measure the time variation of near-surface wind and temperature with depth, to test and refine hypotheses for megadune formation. Field study will consist of surface snowpit and shallow core sampling, ground penetrating radar (GPR) profiling, GPS topographic and ice motion surveys, AWS installation, accumulation/ ablation measurements, subsurface temperature, and firn permeability studies. Field work in two successive seasons is proposed. Continent-wide remote sensing studies of the dunes will be continued, using the new group of instruments that are now, or will shortly be available (e.g., MODIS, MISR, GLAS, AMSR). The earlier study of topographic, passive microwave, and SAR characteristics will be extended, with the intent of determining the relationships of dune amplitude and wavelength to climate parameters, and further development of models of dune formation. Diffusion, ventilation, and vapor transport processes within the dune firn will be modeled as well. A robust program of outreach is planned and reporting to inform both the public and scientists of the fundamental in-situ and remote sensing characteristics of these uniquely Antarctic features will be an important part of the work. Because of their extreme nature, their broad extent, and their potential impact on the climate record, it is important to improve our current understanding of these. Megadunes are a manifestation of an extreme terrestrial climate and may provide insight on past terrestrial climate, or to processes active on other planets. Megadunes are likely to represent an end-member in firn diagenesis, and as such, may have much to teach us about the processes involved.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ICE AUGERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e SNOWPACK TEMPERATURE PROBE; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e PERMEAMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; IN SITU/LABORATORY INSTRUMENTS \u003e CURRENT/WIND METERS \u003e ANEMOMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e SAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e AIR PERMEAMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CURRENT/WIND METERS \u003e ANEMOMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e RADIO \u003e ARGOS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMOMETERS \u003e THERMOMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e WIND PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e DENSIOMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e GAUGES \u003e BALANCE", "is_usap_dc": true, "keywords": "Internal Layering; ICESAT; Vapor-Redeposition; Antarctic; Wind Speed; FIELD INVESTIGATION; Surface Morphology; Antarctica; GROUND-BASED OBSERVATIONS; ARWS; Polar Firn Air; Microstructure; Gas Diffusivity; WEATHER STATIONS; Surface Temperatures; RADARSAT-2; Ice Core; Wind Direction; AWS; Ice Sheet; Snow Pit; Dunefields; Climate Record; Megadunes; GROUND STATIONS; METEOROLOGICAL STATIONS; Antarctic Ice Sheet; Density; Atmospheric Pressure; Firn Permeability; FIELD SURVEYS; Radar; Permeability; Field Survey; Firn Temperature Measurements; Snow Megadunes; Thermal Conductivity; LANDSAT; Firn; Ice Core Interpretation; East Antarctic Plateau; Not provided; Surface Winds; Sublimation; Snow Density; Ice Climate Record; Glaciology; Snow Permeability; Air Temperature; Paleoenvironment; Automated Weather Station", "locations": "Antarctica; Antarctic Ice Sheet; Antarctic; East Antarctic Plateau", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Courville, Zoe; Cathles, Mac; Scambos, Ted; Bauer, Rob; Fahnestock, Mark; Haran, Terry; Shuman, Christopher A.; Albert, Mary R.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e ARWS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e METEOROLOGICAL STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e WEATHER STATIONS; Not provided; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e ICE, CLOUD AND LAND ELEVATION SATELLITE (ICESAT) \u003e ICESAT; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e LANDSAT \u003e LANDSAT; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e RADARSAT \u003e RADARSAT-2", "repo": "USAP-DC", "repositories": "NSIDC; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Characteristics of Snow Megadunes and Their Potential Effect on Ice Core Interpretation", "uid": "p0000587", "west": null}, {"awards": "0232042 Finn, Carol", "bounds_geometry": "POLYGON((139.27539 -82.35733,142.369695 -82.35733,145.464 -82.35733,148.558305 -82.35733,151.65261 -82.35733,154.746915 -82.35733,157.84122 -82.35733,160.935525 -82.35733,164.02983 -82.35733,167.124135 -82.35733,170.21844 -82.35733,170.21844 -82.516831,170.21844 -82.676332,170.21844 -82.835833,170.21844 -82.995334,170.21844 -83.154835,170.21844 -83.314336,170.21844 -83.473837,170.21844 -83.633338,170.21844 -83.792839,170.21844 -83.95234,167.124135 -83.95234,164.02983 -83.95234,160.935525 -83.95234,157.84122 -83.95234,154.746915 -83.95234,151.65261 -83.95234,148.558305 -83.95234,145.464 -83.95234,142.369695 -83.95234,139.27539 -83.95234,139.27539 -83.792839,139.27539 -83.633338,139.27539 -83.473837,139.27539 -83.314336,139.27539 -83.154835,139.27539 -82.995334,139.27539 -82.835833,139.27539 -82.676332,139.27539 -82.516831,139.27539 -82.35733))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 16 Aug 2005 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the Transantarctic Mountains and an adjacent region of East Antarctica. The East Antarctic shield is one of Earth\u0027s oldest and largest cratonic assemblies, with a long-lived Archean to early Paleozoic history. Long-standing interest in the geologic evolution of this shield has been rekindled over the past decade by tectonic models linking East Antarctica with other Precambrian crustal elements in the Rodinia and Gondwanaland supercontinents. It is postulated that the Pacific margin of East Antarctica was rifted from Laurentia during late Neoproterozoic breakup of Rodinia, and it then developed as an active plate boundary during subsequent amalgamation of Gondwanaland in the earliest Paleozoic. If true, the East Antarctic shield played a key role in supercontinent transformation at a time of global changes in plate configuration, terrestrial surficial process, sea level, and marine geochemistry and biota. A better understanding of the geological evolution of the East Antarctic shield is therefore critical for studying Precambrian crustal evolution in general, as well as resource distribution, biosphere evolution, and glacial and climate history during later periods of Earth history. Because of nearly complete coverage by the polar ice cap, however, Antarctica remains the single most geologically unexplored continent. Exposures of cratonic basement are largely limited to coastal outcrops in George V Land and Terre Adelie (Australian sector), the Prince Charles Mountains and Enderby Land (Indian sector), and Queen Maud Land (African sector), where the geology is reasonably well-known. By contrast, little is known about the composition and structure of the shield interior. Given the extensive ice cover, collection of airborne geophysical data is the most cost-effective method to characterize broad areas of sub-ice basement and expand our knowledge of the East Antarctic shield interior. \u003cbr/\u003e\u003cbr/\u003eThis project will conduct an airborne magnetic survey (coupled with ground-based gravity measurements) across an important window into the shield where it is exposed in the Nimrod Glacier area of the central Transantarctic Mountains. Specific goals are to:\u003cbr/\u003e1. Characterize the magnetic and gravity signature of East Antarctic crustal basement exposed at the Ross margin (Nimrod Group),\u003cbr/\u003e2. Extend the magnetic data westward along a corridor across the polar ice cap in order to image the crust in ice-covered areas,\u003cbr/\u003e3. Obtain magnetic data over the Ross Orogen in order to image the ice-covered boundary between basement and supracrustal rocks, allowing us to better constrain the geometry of fundamental Ross structures, and\u003cbr/\u003e4. Use the shape, trends, wavelengths, and amplitudes of magnetic anomalies to define magnetic domains in the shield, common building blocks for continent-scale studies of Precambrian geologic structure and evolution.\u003cbr/\u003e\u003cbr/\u003eHigh-resolution airborne magnetic data will be collected along a transect extending from exposed rocks of the Nimrod Group across the adjacent polar ice cap. The Nimrod Group represents the only bona fide Archean-Proterozoic shield basement exposed for over 2500 km of the Pacific margin of Antarctica. This survey will characterize the geologically well-known shield terrain in this sector using geophysical methods for the first time. This baseline over the exposed shield will allow for better interpretation of geophysical patterns in other ice-covered regions and can be used to target future investigations. In collaboration with colleagues from the BGR (Germany), a tightly-spaced, \"draped\" helicopter magnetic survey will be flown during the 2003-04 austral summer, to be complemented by ground measurements of gravity over the exposed basement. Data reduction, interpretation and geological correlation will be completed in the second year. This project will enhance the education of students, the advancement of under-represented groups, the research instrumentation of the U.S. Antarctic Program, partnerships between the federal government and institutions of higher education, and cooperation between national research programs. It will benefit society through the creation of new basic knowledge about the Antarctic continent, which in turn may help with applied research in other fields such as the glacial history of Antarctica.", "east": 170.21844, "geometry": "POINT(154.746915 -83.154835)", "instruments": "SOLAR/SPACE OBSERVING INSTRUMENTS \u003e MAGNETIC FIELD/ELECTRIC FIELD INSTRUMENTS \u003e MAM", "is_usap_dc": false, "keywords": "Central Transantarctic Mountains; Aeromagnetic Data; HELICOPTER; DHC-6; Not provided", "locations": "Central Transantarctic Mountains", "north": -82.35733, "nsf_funding_programs": null, "paleo_time": null, "persons": "Finn, C. A.; FINN, CAROL", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e DHC-6; AIR-BASED PLATFORMS \u003e ROTORCRAFT/HELICOPTER \u003e HELICOPTER; Not provided", "repositories": null, "science_programs": null, "south": -83.95234, "title": "Collaborative Research: Geophysical Mapping of the East Antarctic Shield Adjacent to the Transantarctic Mountains", "uid": "p0000249", "west": 139.27539}, {"awards": "0088054 Goldstein, Steven", "bounds_geometry": "POLYGON((-180 -39.57,-144 -39.57,-108 -39.57,-72 -39.57,-36 -39.57,0 -39.57,36 -39.57,72 -39.57,108 -39.57,144 -39.57,180 -39.57,180 -42.967,180 -46.364,180 -49.761,180 -53.158,180 -56.555,180 -59.952,180 -63.349,180 -66.746,180 -70.143,180 -73.54,144 -73.54,108 -73.54,72 -73.54,36 -73.54,0 -73.54,-36 -73.54,-72 -73.54,-108 -73.54,-144 -73.54,-180 -73.54,-180 -70.143,-180 -66.746,-180 -63.349,-180 -59.952,-180 -56.555,-180 -53.158,-180 -49.761,-180 -46.364,-180 -42.967,-180 -39.57))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 26 Apr 2005 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the sediment core from the Southern Ocean for paleoenvironmental research. The polar regions are susceptible to the largest changes in climate and are among the least accessible places on Earth. Current concern about the instability of the West Antarctic Ice Sheet has heightened awareness of the vulnerability of polar regions. This proposal seeks to gain a basic understanding of the isotopic characteristics of terrigenous sediment sources derived from Antarctica in the Holocene and Last Glacial Maximum, and their dispersal into the Southern Ocean. Terrigenous clastic sediments are brought to the ocean from continental sources via rivers, ice and wind, and distributed within the ocean by surface and deep currents. At present there are virtually no isotopic data on circumpolar detritus, save a few strontium (Sr) isotopic ratios in the Atlantic sector. This project will fill part of this gap. From the large range in geological ages of crustal provinces of Antarctica, we would predict that there are large isotopic differences in detritus around the continent. The main objectives are to (1) characterize the strontium-neodymium-lead-argon (Sr-Nd-Pb-Ar) isotope compositions of sediment sources derived from Antarctica, (2) to identify the composition and source ages of major ice rafted detritus (IRD) contributions by analyzing individual grains of hornblende and feldspar in conjunction with bulk isotopic analysis, and (3) track sediment dispersal into the Antarctic Circumpolar Current (ACC) during the Holocene and Last Glacial Maximum.\u003cbr/\u003e\u003cbr/\u003eBecause of the paucity of circumpolar data, this research necessarily has a large exploratory component. Consequently, it will provide a basic database for future studies. Nevertheless there are important hypothesis-driven questions that will be addressed in this primary pass. Can lessons learned in North Atlantic IRD studies be applied toward understanding the history of Antarctic ice sheets? Can the large geological variability around the Antarctic margin be treated as a series of natural tracer injections into the ACC, and thus characterize its trajectory, speed, and interaction with other current systems today and in the past? The proposed study is motivated by an exciting set of results from the South Atlantic, showing that detrital Sr isotope ratios are a sensitive current tracer in that region. This research should serve a basic need across many Earth Science disciplines if the use of long-lived radiogenic isotopes (Sr-Nd-Pb-Ar) as tracers of marine sediment sources is successful in elucidating processes related to changing climatic conditions. The results of this study will fill a basic gap in our knowledge of an important region of the Earth. At the same time, it will provide an essential basis for attempting reconstruction of the ACC during the LGM, as well as for future studies of Antarctic geology, ice sheet history, and the Southern Ocean circulation.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -39.57, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Roy, Martin; Hemming, Sidney R.; Goldstein, Steven L.; Van De Flierdt, Christina-Maria", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -73.54, "title": "Establishing the Pattern of Holocene-LGM Changes in Sediment Contributions from Antarctica to the Southern Ocean", "uid": "p0000724", "west": -180.0}, {"awards": "9316564 Mayewski, Paul", "bounds_geometry": null, "dataset_titles": "Ross Ice Drainage System (RIDS) Glaciochemical Analysis; Siple Dome Ice Core Chemistry and Ion Data", "datasets": [{"dataset_uid": "609251", "doi": "", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Mayewski, Paul A.; Kreutz, Karl; Severinghaus, Jeffrey P.; Blunier, Thomas; Dunbar, Nelia; Brook, Edward J.", "repository": "NCEI", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Ice Core Chemistry and Ion Data", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/2461"}, {"dataset_uid": "609266", "doi": "10.7265/N5M906KG", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Snow/ice; Snow/Ice; Snow Pit", "people": "Mayewski, Paul A.; Whitlow, Sallie; Kreutz, Karl; Meeker, Loren D.; Twickler, Mark", "repository": "USAP-DC", "science_program": null, "title": "Ross Ice Drainage System (RIDS) Glaciochemical Analysis", "url": "https://www.usap-dc.org/view/dataset/609266"}], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": "9316564 Mayewski This award is for support for a three year program to provide a high resolution record of the Antarctic climate through the acquisition, analysis, and interpretation of records of atmospheric chemical deposition taken from three ice cores located at sites within or immediately adjacent to the Ross Ice Drainage System (RIDS). These cores include one from Taylor Dome, and two from West Antarctic locations identified as potential deep drilling sites for the WAISCORES program. Collection of the two West Antarctic cores is intended to be a lightweight dry-drilling operation to depths of ~ 200 m, which will provide records of \u003e 2 kyr. Glaciochemical analyses will focus on the major cations and anions found in the antarctic atmosphere, plus methanesulfonic acid and selected measurements of the hydrogen ion, aluminum, iron, and silica. These analyses, and companion stable isotope and particle measurements to be carried out by other investigators require \u003c 7% by volume of each core, leaving \u003e 90% for other investigators and storage at the U.S. National Ice Core Laboratory. These records are intended to solve a variety of scientific objectives while also providing spatial sampling and reconnaissance for future U.S. efforts in West Antarctica. ***", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Magnesium; GROUND STATIONS; Nitrate; Methane Sulfonic Acid; Sodium; Ice Core Chemistry; Ammonium (NH4); Sulfate; Ice Core; Chloride; Potassium (k); Calcium (ca)", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kreutz, Karl; Twickler, Mark; Whitlow, Sallie; Blunier, Thomas; Dunbar, Nelia; Brook, Edward J.; Mayewski, Paul A.; Meeker, Loren D.; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "NCEI", "repositories": "NCEI; USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Ross Ice Drainage System (RIDS) Late Holocene Climate Variability", "uid": "p0000145", "west": null}, {"awards": "8919147 Elliot, David", "bounds_geometry": null, "dataset_titles": "Ice Thickness and Surface Elevation, Southeastern Ross Embayment, West Antarctica", "datasets": [{"dataset_uid": "609099", "doi": "10.7265/N5WW7FKC", "keywords": "Antarctica; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ross Embayment; West Antarctica", "people": "Kempf, Scott D.; Morse, David L.; Bell, Robin; Studinger, Michael S.; Brozena, J. M.; Behrendt, J. C.; Blankenship, Donald D.; Finn, C. A.; Hodge, S. M.; Peters, M. E.", "repository": "USAP-DC", "science_program": null, "title": "Ice Thickness and Surface Elevation, Southeastern Ross Embayment, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/609099"}], "date_created": "Wed, 17 Mar 2004 00:00:00 GMT", "description": "This award will support a combined airborne radar and aeromagnetic survey of two 220 x 330 km regions between the Transantarctica Mountains and Marie Byrd Land during the 1990-91 and 1991-92 field seasons. These efforts will address significant problems identified in the Ross Transect Zone (RTZ) by the National Academy of Sciences (1986) report \"Antarctic Solid Earth Sciences Research,\" and by the report to NSF \"A Plan for a United States Program to Study the Structure and Evolution of the Antarctic Lithosphere (SEAL).\" The surveys will be flown using the NSF/TUD radar and an areomagnetics system mounted in a light aircraft. The grid spacing will be 5 km and navigation will be by radiopositioning. In addition to maps of subglacial topography and magnetic intensity, attempts will be made to reconstruct the position of subglacial diffractors in three dimensions. This reconstruction should give new information about the distribution of escarpments and therefore the tectonic relationships within the region, especially when combined with the magnetic results. These experiments will be conducted by the Byrd Polar Research Center of the Ohio State University and the Water Resources and Geological Divisions of the U.S. Geological Survey.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e ALTIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS", "is_usap_dc": true, "keywords": "Subglacial Topography; SOAR; Airborne Laser Altimeters; Ross Embayment; West Antarctica; Ice Stream; Surface Morphology; Airborne Laser Altimetry; Aerogeophysics; Ice Sheet Thickness; Airborne Radar Sounding; Ice Thickness; West Antarctic Ice Sheet; Ice Surface Elevation; Casertz", "locations": "Ross Embayment; West Antarctica; West Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": null, "persons": "Elliot, David; Bell, Robin; Blankenship, Donald D.; Brozena, J. M.; Finn, C. A.; Hodge, S. M.; Kempf, Scott D.; Behrendt, J. C.; Morse, David L.; Peters, M. E.; Studinger, Michael S.", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Corridor Aerogeophysics of the Southeastern Ross Transect Zone (CASERTZ), Antarctica", "uid": "p0000056", "west": null}, {"awards": "9980691 Wahlen, Martin", "bounds_geometry": null, "dataset_titles": "Atmospheric CO2 Trapped in the Ice Core from Siple Dome, Antarctica", "datasets": [{"dataset_uid": "609202", "doi": "10.7265/N5N877Q9", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; CO2; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Deck, Bruce; Wahlen, Martin; Ahn, Jinho", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Atmospheric CO2 Trapped in the Ice Core from Siple Dome, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609202"}], "date_created": "Thu, 11 Dec 2003 00:00:00 GMT", "description": "9980691\u003cbr/\u003eWahlen\u003cbr/\u003e\u003cbr/\u003eThis award is for support for three years of funding to reconstruct the atmospheric carbon dioxide (CO2) and carbon-13 isotope (d13C) concentration in ice cores from Antarctica over several climatic periods. Samples from the Holocene, the Last Glacial Maximum (LGM)-Holocene transition and glacial stadial/interstadial episodes will be examined. Samples from the Siple Dome ice core drilled in 1998/99 will be made, in addition to measurements from the Taylor Dome and Vostok ice cores. The major objectives are to investigate the phase relationships between variations in the concentration of atmospheric CO2, its carbon isotope composition, and temperature changes (indicated by 18dO and dD of the ice) during deglaciations as well as across rapid climate change events (e.g. Dansgaard-Oeschger events). This will help to determine systematic changes in the global carbon cycle during and between different climatic periods, and to ascertain if the widely spread northern hemisphere temperature stadial/interstadial events produced a global atmospheric carbon dioxide signal. Proven experimental techniques will be used.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "FIELD SURVEYS; Siple Dome; Ice Core; USAP-DC; Carbon Dioxide", "locations": "Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Wahlen, Martin; Ahn, Jinho; Deck, Bruce", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "CO2 and Delta 13CO2 in Antarctic Ice Cores", "uid": "p0000166", "west": null}, {"awards": "9420648 Waddington, Edwin", "bounds_geometry": null, "dataset_titles": "Siple Dome Ice Core Age-Depth Scales", "datasets": [{"dataset_uid": "609130", "doi": "10.7265/N5T151KD", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Nereson, Nadine A.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Ice Core Age-Depth Scales", "url": "https://www.usap-dc.org/view/dataset/609130"}], "date_created": "Tue, 09 Sep 2003 00:00:00 GMT", "description": "This award is for support for a three year program to investigate the response of ice domes, such as Siple Dome in West Antarctica, to changing boundary conditions, for example as arising from fluctuations in thickness or position of bounding ice streams. A range of models will be used, from simple one-dimensional analytical models to coupled dynamic-thermodynamic flow models, to investigate the response of the ice dome to boundary forcing, and the record that boundary forcing can leave in the ice core record. Using radar, temperature, and ice core data from the currently funded field programs on Siple Dome, and ice flux and thickness values from the map view model as boundary conditions, a flow line across Siple Dome will be studied and possible ranges of time scales, the likely origin of ice near the bed, and the basal temperature conditions that exist now and existed in the past will be determined.The response of internal stratigraphy patterns to climate and dynamic forcing effects will be investigated and observed internal layers from ice cores will be used to infer the forcing history.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Ice Sheet; Snow; Not provided; Stratigraphy; Shallow Core; Siple Coast; Antarctica; Ice Core; Siple Dome; Glaciology; Density; Siple; WAISCORES; GROUND STATIONS; GROUND-BASED OBSERVATIONS", "locations": "Antarctica; Siple; Siple Coast; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Nereson, Nadine A.; Waddington, Edwin D.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Ice Modelling Study of Siple Dome: WAIS Ice Dynamics, WAISCORES Paleoclimate and Ice Stream/Ice Dome Interactions", "uid": "p0000058", "west": null}, {"awards": "9615347 Conway, Howard", "bounds_geometry": null, "dataset_titles": "Roosevelt Island Bedrock and Surface Elevations; Roosevelt Island Ice Core Density and Beta Count Data", "datasets": [{"dataset_uid": "609139", "doi": "10.7265/N55718ZW", "keywords": "Antarctica; Beta Count; Density; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; Roosevelt Island", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Ice Core Density and Beta Count Data", "url": "https://www.usap-dc.org/view/dataset/609139"}, {"dataset_uid": "609140", "doi": "10.7265/N51J97NB", "keywords": "Antarctica; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Roosevelt Island; Solid Earth", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Bedrock and Surface Elevations", "url": "https://www.usap-dc.org/view/dataset/609140"}], "date_created": "Fri, 23 May 2003 00:00:00 GMT", "description": "This award is for two years of support to perform radar investigations across former shear margins at Roosevelt Island and Ice Stream C in order to measure changes in the configuration and continuity of internal layers and the bed. The broad goal of these investigations is to gain an understanding of ice stream flow and the timing and mechanisms of ice stream shutdown. A high-resolution short-pulse radar system will be used for detailed examination of the uppermost hundred meters of the firn and ice, and a monopulse sounding-radar system will be used to image the rest of the ice column (including internal layers) and the bed. Changes in the shape and continuity of layers will be used to interpret mechanisms and modes of ice stream flow including the possible migration of stagnation fronts and rates of shut-down. Variations in bed reflectivity will be used to deduce basal hydrology conditions across lineations. Accumulation rates deduced from snow pits and shallow cores will be used to estimate near-surface depth-age profiles. Improved understanding of ice stream history opens the possibility of linking changes in the West Antarctic ice sheet with the geologic evidence from Northern Victoria Land and the ocean record of the retreat of the grounding line in the Ross Sea.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e RA; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Radioactive Decay; Radar Echo Sounder; Antarctica; Radar Altimetry; Densification; Bedrock Elevation; Ice Sheet Elevation; Satellite Radar Data; GROUND-BASED OBSERVATIONS; Radar; Ice Core; Snow Stratigraphy; Terrain Elevation; Antarctic Ice Sheet; Stable Isotopes; Ice Surface Elevation; Surface Elevation; Glaciology; Snow Densification; Ice Core Data; GROUND STATIONS; Not provided; Altimetry; Antarctic; Ice Core Stratigraphy; Ice Stratigraphy", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Radar Investigations of Former Shear Margins: Roosevelt Island and Ice Stream C", "uid": "p0000164", "west": null}, {"awards": "9980538 Lohmann, Kyger", "bounds_geometry": "POINT(-56 -64)", "dataset_titles": "Stable isotope and minor element proxies for Eocene climate of Seymour Island, Antarctica", "datasets": [{"dataset_uid": "600019", "doi": "", "keywords": null, "people": "Lohmann, Kyger", "repository": "USAP-DC", "science_program": null, "title": "Stable isotope and minor element proxies for Eocene climate of Seymour Island, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600019"}], "date_created": "Mon, 11 Jun 2001 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research for construction of a long-term record of climate during the late Cretaceous and early Paleogene to assess the annual seasonality in temperature on the coastal margin of Antarctica. Stable isotope and element compositions of well-preserved bivalve shells collected on Seymour Island will be the primary source of data used to reconstruct paleoenvironmental conditions. Seasonal temperature records collected through high-resolution sampling along growth structures in bivalve shells will allow seasonality to be assessed during different climate states and during periods of rapid climate change. In addition, high stratigraphic resolution will enable this project to detect the presence and frequency of short-lived thermal excursions that may have extended to such high latitudes.\u003cbr/\u003e\u003cbr/\u003eTo compile a reliable temporal record of paleoclimate, two major avenues of investigation will be undertaken: 1) precise stratigraphic (and therefore, temporal) placement of fossils over a large geographic area will be employed through the use of a graphical technique employing geometric projections; 2) stable isotope and elemental analyses will be performed to derive paleotemperatures and to evaluate diagenetic alteration of shell materials. To provide realistic comparisons of paleotemperatures across stratigraphic horizons, this study will focus on a single taxon, thus avoiding complications due to the mixing of faunal assemblages that have been encountered in previous studies of this region.\u003cbr/\u003e\u003cbr/\u003eThe near-shore marine fossil record on Seymour Island provides a unique opportunity to address many questions about the Antarctic paleoenvironment, including the relation between seasonality and different climate states, the influence of climate on biogeographic distribution of specific taxa, the effect of ice-volume changes on the stable isotope record from the late Cretaceous through the Eocene, and the plausibility of high-latitude bottom water formation during this time interval. In particular, information that will be collected concerning patterns of seasonality and the presence (or absence) of short-lived thermal excursions will be extremely valuable to an understanding of the response of high latitude sites during climate transitions from globally cool to globally warm conditions.", "east": -56.0, "geometry": "POINT(-56 -64)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided; Bivalves; Geochemical Composition; Carbon Isotopes; Climate", "locations": null, "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e PALEOGENE \u003e EOCENE", "persons": "Lohmann, Kyger; Barrera, Enriqueta", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.0, "title": "Evolution of Sea Surface Temperatures in the Coastal Antarctic Paleoenvironment During the Late Cretaceous and Paleogene", "uid": "p0000613", "west": -56.0}, {"awards": "9725305 Severinghaus, Jeffrey", "bounds_geometry": null, "dataset_titles": "Firn Air Isotope and Temperature Measurements from Siple Dome and South Pole", "datasets": [{"dataset_uid": "609098", "doi": "10.7265/N51N7Z2P", "keywords": "Antarctica; Atmosphere; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciology; Isotope; Paleoclimate; Siple Dome; Snow/ice; Snow/Ice; South Pole; Temperature", "people": "Grachev, Alexi; Battle, Mark; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Firn Air Isotope and Temperature Measurements from Siple Dome and South Pole", "url": "https://www.usap-dc.org/view/dataset/609098"}], "date_created": "Mon, 01 Jan 2001 00:00:00 GMT", "description": "9725305 Severinghaus This award supports a project to develop and apply a new technique for quantifying temperature changes in the past based on the thermodynamic principle of thermal diffusion, in which gas mixtures in a temperature gradient become fractionated. Air in polar firn is fractionated by temperature gradients induced by abrupt climate change, and a record of this air is preserved in bubbles in the ice. The magnitude of the abrupt temperature change, the precise relative timing, and an estimate of the absolute temperature change can be determined. By providing a gas-phase stratigraphic marker of temperature change, the phasing of methane (with decadal precision) and hence widespread climate change (relative to local polar temperature changes) can be determined (across five abrupt warming events during the last glacial period).", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS", "is_usap_dc": true, "keywords": "Isotopic History; GROUND STATIONS; Thermal Diffusion; Firn Temperature Measurements; Not provided; Oxygen Isotope; Trapped Air Bubbles; Shallow Firn Air; Firn Air Isotope Measurements; Seasonal Temperature Gradients; Mass Spectrometry; GROUND-BASED OBSERVATIONS; Thermal Fractionation; Polar Firn Air; Isotopic Anomalies; Xenon; Atmospheric Gases; Argon Isotopes; Siple Dome; Krypton; Nitrogen Isotopes; Seasonal Temperature Changes; Antarctica; Ice Core Gas Records; Firn Air Isotopes; Mass Spectrometer; South Pole; Firn Isotopes; Borehole", "locations": "Antarctica; Siple Dome; South Pole", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Battle, Mark; Grachev, Alexi; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Thermal Fractionation of Firn Air and the Ice Core Record of Abrupt Interstadial Climate Change", "uid": "p0000160", "west": null}, {"awards": "9527329 Kyle, Philip", "bounds_geometry": "POLYGON((-180 -65,-175.5 -65,-171 -65,-166.5 -65,-162 -65,-157.5 -65,-153 -65,-148.5 -65,-144 -65,-139.5 -65,-135 -65,-135 -66.5,-135 -68,-135 -69.5,-135 -71,-135 -72.5,-135 -74,-135 -75.5,-135 -77,-135 -78.5,-135 -80,-139.5 -80,-144 -80,-148.5 -80,-153 -80,-157.5 -80,-162 -80,-166.5 -80,-171 -80,-175.5 -80,180 -80,177 -80,174 -80,171 -80,168 -80,165 -80,162 -80,159 -80,156 -80,153 -80,150 -80,150 -78.5,150 -77,150 -75.5,150 -74,150 -72.5,150 -71,150 -69.5,150 -68,150 -66.5,150 -65,153 -65,156 -65,159 -65,162 -65,165 -65,168 -65,171 -65,174 -65,177 -65,-180 -65))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 01 Jan 1970 00:00:00 GMT", "description": "Kyle OPP 9527329 Abstract The Cape Roberts Project is an international drilling project to obtain a series of cores from the sedimentary strata beneath the sea floor off Cape Roberts in the Ross Sea. The project is a joint venture by scientists from the national Antarctic programs of Germany, Italy, New Zealand, the United Kingdom., Australia, and the United States. Drilling will continuously core a composite section of sediments over 1500 m thick which is expected to represent parts of the time period between 30 and more than 100 million years ago. The principle objectives of this component of the project will be to examine the record of igneous material in the drill core and provide high precision 40Ar/39Ar dates from tephra (volcanic ash) layers, disseminated ash, feldspars and epiclastic volcanic detrital grains to constrain depositional age and provenance of the sediments in the cores. This project will contribute to general geologic logging of the core and will characterize any igneous material using electron microprobe, x-ray fluorescence (XRF) and instrumental neutron activation analysis (INAA) analyses. The presence of alkalic volcanic detritus from the Cenozoic McMurdo Volcanics will constrain the initiation of this phase of volcanism and improve our understanding of the relationship between volcanism and tectonism. The influx of sediments eroded from Jurassic Kirkpatrick Basalts and Ferrar Dolerites will be used to time the unroofing and rates of uplift of the Transantarctic Mountains. Geochemical analyses of core samples will examine the geochemistry and provenance of the sediments.", "east": -135.0, "geometry": "POINT(-172.5 -72.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ROCK CORERS", "is_usap_dc": false, "keywords": "Radiometric Dating; Radiometric Ages; Argon-Argon Dates; Geochronology; 40Ar/39Ar; Tephra; Geochemistry; Cape Roberts Project; Geology; Not provided", "locations": null, "north": -65.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kyle, Philip; Krissek, Lawrence", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -80.0, "title": "The Cape Roberts Project: Volcanic Record, Geochemistry and 40Ar/39Ar Chronology", "uid": "p0000050", "west": 150.0}]
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Non-technical description<br/>Marine invertebrates often have mutually beneficial partnerships with microorganisms that biosynthesize compounds with nutritive or defensive functions and are integral for survival. Additionally, these “natural products” often have bioactive properties with human health applications fighting infection or different types of cancer. This project focuses on the ascidian (“sea squirt”) Synoicum adareanum, found in the Anvers Island region of the Antarctic Peninsula, and was recently discovered to contain high levels of a natural product, palmerolide A (palA) in its tissues. The microorganism that produces palA is a new bacterial species, Candidatus Synoicihabitans palmerolidicus, found in a persistent partnership with the sea squirt. There is still much to be learned about the fundamental properties of this sea squirt-microbe-palA system including the geographical range of the animal-microbe partnership, its chemical and microbiome complexity and diversity, and the biological effect of palA in the sea squirt. To address these questions, this multidisciplinary research team will investigate the sea squirt-microbiome partnership in the Antarctic Peninsula and McMurdo Sound regions of the Ross Sea using a state-of-the-art strategy that will advance our understanding of the structural and functional features of the sea squirt and microbiome in detail, and reveal the roles that the palA natural product plays in the host ecology in its native Antarctic seafloor habitat. The project will broaden diversity and provide new opportunities for early career students and postdoctoral researchers to participate in field and laboratory-based research that builds an integrative understanding of Antarctic marine biology, ecology, physiology and chemistry. In addition, advancing the understanding of palA and its biological properties may be of future benefit to biomedicine and human health.<br/><br/>Technical description<br/>Marine invertebrates and their associated microbiomes can produce bioactive natural products; in fact, >600 such compounds have been identified in species from polar waters. Although such compounds are typically hypothesized to serve ecological roles in host survival through deterring predation, fouling, and microbial infection, in most cases neither the producing organism nor the genome-encoded biosynthetic enzymes are known. This project will study an emerging biosynthetic system from a polar ascidian-microbe association that produces palA, a natural product with bioactivity against the proton-pumping enzyme V-type H+-ATPase (VHA). The objectives include: (i) Determining the microbiome composition, metabolome complexity, palA levels, and mitochondrial DNA sequence of S. adareanum morphotypes at sites in the Antarctic Peninsula and in McMurdo Sound, (ii) Characterizing the Synoicum microbiome using a multi-omics strategy, and (iii) Assessing the potential for co-occurrence of Ca. S. palmerolidicus-palA-VHA in host tissues, and (iv) exploring the role of palA in modulating VHA activity in vivo and its effects on ascidian-microbe ecophysiology. Through a coupled study of palA-producing and non-producing S. adareanum specimens, structural and functional features of the ascidian microbiome metagenome will be characterized to better understand the relationship between predicted secondary metabolite pathways and whether they are expressed in situ using a paired metatranscriptome sequencing and secondary metabolite detection strategy. Combined with tissue co-localization results, functional ecophysiological assays aim to determine the roles that the natural product plays in the host ecology in its native Antarctic seafloor habitat. The contributions of the project will inform this intimate host-microbial association in which the ascidian host bioaccumulates VHA-inhibiting palA, yet its geo-spatial distribution, cellular localization, ecological and physiological role(s) are not known. In addition to elucidating the ecophysiological roles of palA in their native ascidian-microbe association, the results will contribute to the success of translational science, which aligns with NSF’s interests in promoting basic research that leads to advances in Biotechnology and Bioeconomy. The project will also broaden diversity and provide new opportunities for early career students and postdoctoral researchers to participate in field and laboratory-based research that builds an integrative understanding of Antarctic marine biology, ecology, physiology and chemistry.<br/><br/>This award reflects NSF''s statutory mission and has been deemed worthy of support through evaluation using the Foundation''s intellectual merit and broader impacts review criteria.
Phytoplankton, or microscopic marine algae, are an important part of the carbon cycle and can lower the rates of atmospheric carbon dioxide by transferring the atmospheric carbon into the oceans. The concentration of phytoplankton in the Southern Ocean is regularly limited by the availability of marine iron. This in turn influences the rate of carbon transfer from the atmosphere to the ocean. The primary source of iron in the Southern Ocean is eroded continental rock. Understanding the current and future sources of iron to the Southern Ocean as a result of increased melting of terrestrial glaciers is necessary for predicting future concentrations of Southern Ocean phytoplankton and the subsequent influence on the carbon cycle. A poorly understood source of iron to the Southern Ocean is stream input from ice-free regions such as the McMurdo Dry Valleys in Antarctica. This source of iron is likely to become larger if glaciers retreat. This study investigates the sources and amount of iron transported by McMurdo Dry Valley streams directly into the Southern Ocean. Because not all forms of iron can be used by phytoplankton, experiments will be performed to determine how available iron is to phytoplankton and how iron mixes with seawater. Immersive 360-degree video, infographics, and educational videos of findings from this project will be shared on social media, at schools and science events, and in an urban science center.<br/><br/>In the Southern Ocean (SO) there is an excess of macronutrients but regional primary production is limited or co-limited due to iron. An addition of iron to the ocean will affect biochemical cycles, increase primary production, and affect the structure and composition of phytoplankton communities in the SO. Iron flux to the SO is globally significant, as increased Fe fertilization leads to increased carbon sequestration which acts as a negative feedback to increased atmospheric pCO2. One source of potentially bioavailable iron to the coastal regions of the SO is from direct sub-aerial stream discharge in ice-free areas of Antarctica, a source that may become more important if terrestrial glaciers retreat. It is imperative to understand the source, nature, potential fate, and flux of iron to the SO if better predictive models for the carbon cycle and atmospheric chemistry are to be developed. This project will investigate in-stream processes and characteristics controlling dissolved iron draining into the Ross Sea including photoreduction, temperature, and complexation with organic matter. The novel study will quantify bioavailability of particulate iron and bioavailability of dissolved iron in Antarctic in streams draining into the SO. On-site speciation measurements will be performed on dissolved iron species, particulate iron speciation will be determined using high-resolution spectroscopy, mixing experiments will be performed with coastal marine water, and the bioavailability of Fe will be determined through marine bioassays. This project will provide two students with valuable Antarctic field experience and reach thousands of individuals through existing partnerships with K-12 schools, public STEM events, an urban science center, and a strong social media presence.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
MacAyeal, Douglas; Banwell, Alison; Campbell, Seth; Schild, Kristin; Cassoto, Ryan
No dataset link provided
Non-Technical Abstract:<br/>This project explores the areas or crash-zones where floating ice shelves in Antarctica compressively flow against obstructions such as islands and plugs of stagnant ice frozen to the sea bed. The significance of these crash-zones is that they are responsible for generating the resistive forces that allow ice shelves to slow down the flow of ice farther inland into the ocean. Ice conditions within these boundaries thus determine how Antarctica’s ice sheets contribute to sea-level rise. The research will feature on-the-ice glaciological and geophysical field measurements near pressure ridges near Scott Base and the transition to the ice road where large wave-like pressure ridges form on the ice-shelf surface. This field area is along the coast of Ross Island adjacent to major logistical stations of the US and New Zealand Antarctic programs. Thus the research will help station managers better preserve one of the key roadways that connects the stations to the major runway used to fly to virtually all other parts of Antarctica. The research will also interact with educational programs such as featured in the long-standing Juneau Icefield Research Project as well as potential involvement of an artist from the US Antarctic Program’s Polar STEAM in the second field season.<br/><br/>Technical Abstract:<br/>This project explores the dynamics of boundaries where ice shelves compressively flow against obstructions such as islands and areas of grounded ice. The significance of these boundaries is that they are responsible for generating the resistive forces that allow ice shelves to impede or slow down the flow of grounded inland ice into the ocean. Ice conditions within these boundaries thus determine how Antarctica’s ice sheets contribute to sea-level rise. The research will feature glaciological and geophysical field surveys in a compressive boundary area near pressure ridges adjacent to Scott Base and the transition to the ice road along the coast of Ross Island, an area affecting access to major logistical hubs of the US and New Zealand Antarctic programs. Field data will be combined with remote sensing, numerical modeling and theory development to answer key questions about the dynamics of compressive boundaries such as: is there a limit to compressive stress due to ice fracture and the bending of the ice shelf into sinusoidal pressure ridges? Over what time scales does this compressive stress build, fluctuate and decay, and how is it related to the processes that form rumples? Are there ways in which the ridges actually protect the compressive boundary from damage such as by setting up a means to scatter ocean swell impinging from the open ocean? How should compressive ice-shelf boundaries be represented in large scale ice-sheet/shelf models for the prediction of future sea-level rise? A variety of broader impact work will be done both specifically targeting the research field area and more broadly addressing scientific and societal concerns. The field area contains a critical logistics roadway that connects McMurdo Station, Scott Base and a runway essential for continent-wide air logistics. The project will inform how to stabilize the roadway against excessive damage from summer ablation and other factors. Other broader impacts include: (a) Open-Science evaluation of climate systems engineering strategies for glacial geoengineering mitigation of sea-level rise, (b) cooperation with the Juneau Icefield Research Program (JIRP) education component, (c) support and facilitation of an online FieldSafe workshop and associated panel discussion to support early-career Antarctic field teams to mitigate environmental and interpersonal risks in remote field sites, and (d) potential involvement of an artist from the US Antarctic Program’s Polar STEAM in the second field season.<br/><br/>This award reflects NSF''s statutory mission and has been deemed worthy of support through evaluation using the Foundation''s intellectual merit and broader impacts review criteria.
Gentoo penguins (Pygoscelis papua) inhabit one of the fastest warming regions on Earth, the Western Antarctic Peninsula (WAP), where environmental shifts are measured in years, not decades. Despite this, the species is flourishing, growing in numbers and colonizing new habitats while sister species, such as Adélie penguins (P. adeliae), are declining in the region. This project will investigate to what extent epigenetics contributes to the success of gentoo penguins. Epigenetic variation is controlled by modifications to DNA or chromatin structure that affect the expression of genes, rather than changes to the underlying DNA sequence. This project will improve the understanding of gentoo penguin adaptation to climate change, and whether it is a result of increased flexibility in behavior and physiology driven by a greater capacity for epigenetic changes (i.e., epigenetic potential). The most studied form of epigenetic variation is the profiling of DNA methylation patterns. Environmental effects can trigger changes in DNA methylation that target specific tissues, allowing for localized gene expression shifts that result in modifications to the phenotype of an organism without any alteration to the underlying genotype. Given that epigenetic variation between populations often exceeds genetic variation, fine-scale genetic differentiation observed amongst gentoo penguin colonies suggests the possibility for local adaptation via even more divergent epigenetic changes and provides a framework for examining epigenetic variation across the gentoo penguin breeding range along multiple ecological axes. The researchers will test this by comprehensively characterizing the epigenomic profiles via patterns of DNA methylation in wild gentoo and Adélie penguins using cutting-edge high-resolution genomics techniques. Specifically, they will investigate whether gentoo penguins exhibit a greater degree of differences in DNA-methylation than underlying genetic differences, suggesting such epigenetic variation is driven by external environmental variables, potentially leading to improved capacity for local adaptation. This project will explore whether epigenetic potential may be selected for in individuals who disperse to new colony locations by comparing older, established colonies to new colonies at the range-edge. By implementing cutting-edge epigenetic methods in wild populations of gentoo penguins, this project will help address ecological questions on environmental plasticity that will impact conservation efforts and decisions on Marine Protected Areas (MPAs) on the Antarctic Peninsula.
Part I: Nontechnical description The ecologically important notothenioid fish of the Southern Ocean surrounding Antarctica will be studied to address questions central to polar, evolutionary, and adaptational biology. The rapid diversification of the notothenioids into >120 species following a period of Antarctic glaciation and cooling of the Southern Ocean is thought to have been facilitated by key evolutionary innovations, including antifreeze glycoproteins to prevent freezing and bone reduction to increase buoyancy. In this project, a large dataset of genomic sequences will be used to evaluate the genetic mechanisms that underlie the broad pattern of novel trait evolution in these fish, including traits relevant to human diseases (e.g., bone density, renal function, and anemia). The team will develop new STEM-based research and teaching modules for undergraduate education at Northeastern University. The work will provide specific research training to scholars at all levels, including a post-doctoral researcher, a graduate student, undergraduate students, and high school students. The team will also contribute to public outreach, including, in part, the develop of teaching videos in molecular evolutionary biology and accompanying educational supplements. <br/><br/> Part II: Technical description The researchers will leverage their comprehensive notothenioid phylogenomic dataset comprising >250,000 protein-coding exons and conserved non-coding elements across 44 ingroup and 2 outgroup species to analyze the genetic origins of three iconic notothenioid traits: (1) loss of erythrocytes by the icefish clade in a cold, stable and highly-oxygenated marine environment. (2) reduction in bone mass and retention of juvenile skeletal characteristics as buoyancy mechanisms to facilitate foraging. And (3) loss of kidney glomeruli to retain energetically expensive antifreeze glycoproteins. The team will first track patterns of change in erythroid-related genes throughout the notothenioid phylogeny. They will then examine whether repetitive evolution of a pedomorphic skeleton in notothenioids is based on parallel or divergent evolution of genetic regulators of heterochrony. Third, they will determine whether there is mutational bias in the mechanisms of loss and re-emergence of kidney glomeruli. Finally, identified genetic mechanisms of evolutionary change will be validated by experimental testing using functional genomic strategies in the zebrafish model system.
Marine ice sheets are low-pass filters of climate variability that take centuries to adjust to interior and near-terminus changes in mass balance. Constraining these century-scale changes from satellite observations that span only the last 40 years is challenging. Here, we take a different approach of carefully synthesizing different data sets to infer changes in the configurations of van der Veen and Mercer Ice Streams on the Siple Coast over the past 3000 years from englacial features encoded in ice-penetrating radar data. Englacial radar data from Conway Ridge reveal smooth, surface conformal layers overlying disrupted stratigraphy that suggest the van der Veen Ice Stream was 40 km wider over 3000 years ago. Englacial layer dating indicates that the ice stream narrowed to its present configuration between $\sim3000$ and $\sim1000$ years ago. Similarly disrupted stratigraphy and buried crevasses suggest that ice flowing from Mercer to Whillans Ice Stream across the northwestern tip of the ridge slowed shortly after. Using an ice-flow model capable of simulating shear margin migration, we evaluate whether small changes in ice thickness can lead to large changes in shear margin location. Our results suggest that the tip of Conway Ridge is sensitive to thinning and thickening, and that when the basal strength at the tip of the ridge increases with the height above flotation, the ice sheet shear margins can change quickly.
Ice penetrating radar is one of the primary tools that researchers use to study ice sheets and glaciers. With radar, it is possible to see a cross-section of the ice, revealing internal layers and the shape of the rocks under the ice. Among other things, this is important for calculating how much potential sea level change is locked up in the polar ice sheets, and how stable the ice sheets are likely to be in a warming world. This type of data is logistically challenging and expensive to collect. Historically, individual research groups have obtained funding to collect these data sets, and then the data largely stayed within that institution. There has been a recent push to make more and more data openly available, enabling the same datasets to be used by multiple research groups. However, it is still difficult to figure out what data is available because there is no centralized index. Additionally, each group releases data in a different format, which creates an additional hurdle to its use. This project addresses both of those challenges to data reuse by providing a unified tool for discovering where ice penetrating radar data already exists, then allowing the researcher to download and visualize the data. It is integrated into open-source mapping software that many in the research community already use, and makes it possible for non-experts to explore these datasets. This is particularly valuable for early-career researchers and for enabling interdisciplinary work. The US alone has spent many tens of millions of dollars on direct grants to enable the acquisition and analysis of polar ice penetrating radar data, and even more on the associated infrastructure and support costs. Unfortunately, much of these data is not publicly released, and even the data that has been released is not easily accessible. There is significant technical work involved in figuring out how to locate, download and view the data. This project is developing a tool that will both lower the barrier to entry for using this data and improve the workflows of existing users. Quantarctica and QGreenland have rapidly become indispensable tools for the polar research community, making diverse data sets readily available to researchers. However, ice penetrating radar is a major category of data that is not currently supported ? it is possible to see the locations of existing survey lines, and the ice thickness maps that have been interpreted from their data, but it is not readily possible to see the radargrams themselves in context with all of the other information. This capability is important because there is far more visual information contained in a radargram than simply its interpreted basal elevation or ice thickness. This project is developing software that will enable researchers to to view radargram images and interpreted surface and basal horizons in context with the existing map-view datasets in Quantarctica and QGreenland. A data layer shows the locations of all known ice penetrating radar surveys, color-coded based on availability. This layer enables data discovery and browsing. The plugin itself interacts with the data layer, first to download selected data, then to visualize the radargrams along with a cursor that moves simultaneously along the radargram and along the map view, making it straightforward to determine the precise geolocation of radar features.
The Amundsen Sea, near the fastest melting Antarctic glaciers, hosts one of the most productive polar ecosystems in the world. Phytoplankton serve as the base of the food chain, and their growth also removes carbon dioxide from the atmosphere. Phytoplankton growth is fertilized in this area by nutrient iron, which is only present at low concentrations in seawater. Prior studies have shown the seabed sediments may provide iron to the Amundsen Sea ecosystem. However, sediment sources of iron have never been studied here directly. This project fills this gap by analyzing sediments from the Amundsen Sea and investigating whether sediment iron fertilizes plankton growth. The results will help scientists understand the basic ecosystem drivers and predict the effects of climate change on this vibrant, vulnerable region. This project also emphasizes inclusivity and openness to the public. The researchers will establish a mentoring network for diverse polar scientists through the Polar Impact Network and communicate their results to the public through the website CryoConnect.org. <br/><br/>This project leverages samples already collected from the Amundsen Sea (NBP22-02) to investigate sediment iron (Fe) cycling and fluxes. The broad questions driving this research are 1) does benthic Fe fertilize Antarctic coastal primary productivity, and 2) what are the feedbacks between benthic Fe release and carbon cycling in the coastal Antarctic? To answer these questions, the researchers will analyze pore water Fe content and speciation and calculate fluxes of Fe across the sediment-water interface. These results will be compared to sediment characteristics (e.g., organic carbon content, reactive Fe content, proximity to glacial sources) to identify controls on benthic Fe release. This research dovetails with and expands on the science goals of the ?Accelerating Thwaites Ecosystem Impacts for the Southern Ocean? (ARTEMIS) project through which the field samples were collected. In turn, the findings of ARTEMIS regarding modeled and observed trace metal dynamics, surface water productivity, and carbon cycling will inform the conclusions of this project, allowing insight into the impact of benthic Fe in the whole system. This project represents a unique opportunity for combined study of the water column and sediment biogeochemistry which will be of great value to the marine biogeochemistry community and will inform future sediment-ocean studies in polar oceanography and beyond.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Lamont-Doherty Earth Observatory of Columbia University was awarded a multi-year grant (May 1, 2010- April 30, 2015) to develop an ice imaging system, or "IcePod," for use in measuring the surface and subsurface topography of ice sheets. IcePod will enable research on the effects of global climate change on ice sheets and the effects of sub-glacial water on potential sea-level rise. IcePod sensors are contained in a Common Science Support Pod and operated on NYANG LC-130 aircraft during routine and targeted missions over Greenland and Antarctica. The IcePod instrument package consists of ice-penetrating radar, infrared and visible cameras, laser altimeter, inertial measurement unit, GPS receiver and data acquisition system. IcePod will also enable other instruments to be used in the modular Common Science Support Pod, and will become a shared community research facility providing data to the science community. Funding will support activities in both Greenland and Antarctica needed to commission IcePod, to develop a data reduction flow and data delivery system for IcePod data, and to engineer a UPS to provide IcePod with clean, reliable power for system operation. <br/><br/>Evidence from satellites has documented that the amount of ice in both the earth's polar regions is decreasing as global temperatures increase. Understanding how this change is occurring and building an understanding of how fast these continent-sized pieces of ice will change in the future, is critical as society develops plans for adapting to changing coastlines. To measure change and understand the processes driving these changes requires the capacity to image the polat ice sheets and oceans from long-range aircraft. This award supplemented the original MRI-R2 program that developed innovative airborne imagery technology called IcePod. IcePod can be mounted on any LC-130, the aircraft used in the polar regions, for the major logistical support. The IcePod system was developed by engineers and scientists at Columbia University, working in close collaboration with the New York Air National Guard, who operate the ski-equipped LC-130 aircraft for the National Science Foundation in Antarctica and Greenland. The IcePod instrumentation package presently consists of: a scanning laser for precise measurements of the ice surface, visible and infrared imaging cameras to document the ice surface structure and temperature, ice-penetrating radar to recover the ice thickness and constrain the distribution of water at the ice sheet bed, and shallow-ice radar to measure snow accumulation. A magnetometer system is mounted inside the pod to recover information on the solid earth structure. Positioning of the IcePod during flights and the measurements are provided by precision GPS satellite data and inertial technology. A gravimeter, using its own rack, is also employed in conjunction with the IcePod sensor suite. The final commissioning of the system occurred in November - December 2014 in Antarctica as stipulated in the award. The IcePod was successfully operated in full polar conditions with a series of flights from McMurdo Station over the Ross Ice Shelf, the Ross Sea, the Dry Valleys, the Transantarctic Mountains and to South Pole. Protocol was also developed for data handling, robust data reduction, workflow and quality control and archiving of data. <br/><br/>The system is now available to the polar community for novel imaging applications.
General abstract<br/><br/>Most organisms alternate between life stages that vary in the number and arrangement of their chromosomes, in the number of cells they possess, and in the environmental conditions in which they are best adapted to live. Much of what we understand about these alternations comes from organisms like animals and land plants in which one of the two stages dominates the life cycle with the other small and short-lived. However, across the tree of life there are countless examples of organisms in which both stages are of long duration, multicellular, or both. These life cycles challenge common ideas used to explain ecological and evolutionary patterns we see in nature. Macroalgae (seaweeds) display a wide range of life cycle types and consequently are excellent models to test and expand ideas about how life cycles evolve. Undersea forests of seaweeds with a variety of life cycle types dominate the shallow waters of the western Antarctic Peninsula where they are ecologically important and, for most of the species, at the southern end of their geographic range. Using existing samples from previous expeditions to Antarctica, the investigators are uniquely positioned to test and expand knowledge of life cycle evolution and how this intersects with reproductive mode variation. This project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the public. The project will support a postdoctoral scholar as well as a faculty member new to US Antarctic research. The investigators will take advantage of an existing program to include high school or undergraduate students in the work which will also expand mentorship experience for the postdoc. All team members will contribute by writing for blogs produced by professional societies for the public. <br/><br/><br/>Technical abstract<br/><br/>Existing macroalgal taxa samples from across a latitudinal gradient in the western Antarctic Peninsula will be used to explore patterns of genetic diversity from the center to the southern latitudinal limits of their range. Not only will genetic diversity be documented for an understudied and critical group of Antarctic organisms, but how it changes with latitude, compounded by high levels of endemism, will be explored. This will be accomplished by (i) characterization of latitudinal gradients in genetic diversity of many species and (ii) determination of the reproductive system of five focal foundation species. At present, there are few genetic data for macroalgae, dominant primary producers in coastal ecosystems around the world. This gap is particularly acute along Antarctic coastlines that are experiencing rapid climate change. Furthermore, Antarctica is isolated by the Southern Ocean, decreasing the likelihood of regular migration from other land masses. Latitudinal reproductive system patterns are predicted to be largely driven by recolonization events that increase with latitude due to changes in iceberg scour and sea ice coverage. Thus, Antarctica is the best place to understand what processes underlie reproductive mode variation in populations that are isolated, including many endemic taxa, while simultaneously extending our knowledge about how marginal environments converge with complex life cycles.<br/><br/>This award reflects NSF''s statutory mission and has been deemed worthy of support through evaluation using the Foundation''s intellectual merit and broader impacts review criteria.
Radiocarbon dating is arguably the most common method for dating Quaternary deposits. However, accurate age assignments using radiocarbon dating are dependent on knowing the radiocarbon reservoir. For the coastal waters across Antarctica, the radiocarbon reservoirs show significant variation, ranging from 700 to 6,000 years depending on the material dated and the period in question. In this study, we examine the radiocarbon reservoir age for the shallow waters of the Southern Ocean using 23 whale bones salvaged from whaling stations operating on or near the Western Antarctic Peninsula between 1904 and 1916. The species origin of the bones had been identified previously as humpback, fin, or blue whales using sequences of mitochondrial (mt)DNA. We find an average reservoir age of 1050 +/- 135 years for these 23 whale bones, with a <100 year difference in the reservoir age value by species. A comparison between our results and other studies through the Holocene suggest that the Southern Ocean surface water radiocarbon reservoir age has not significantly changed for the last 14,000 years. Combining our new ages with existing data sets provides insight to the stability of the Southern Ocean marine radiocarbon reservoir age, enhancing our understanding of ocean ventilation and upwelling dynamics throughout the Holocene.
Kreutz, Karl; Mukhopadhyay, Sharmila M; Allen, Katherine A; Mayewski, Paul A.; Kurbatov, Andrei V.
No dataset link provided
This award is for acquisition of new instrumentation to support acquisition of the new LA-HR-ICPMS instrumentation for the trace-element analysis of various environmental samples. This instrumentation will replace the original (and heavily used over two decades) ThermoScientific Element2 ICP-MS installed at the University of Maine?s Climate Change Institute (CCI). The new acquisition will significantly expand research capabilities of the CCI/ICP-MS Facility to improve the analysis of aqueous samples, supplemented with a laser ablation (LA) front end for ice, biological, and other solid materials. The current ICP-MS Facility was established in 2002 with an NSF/MRI award, which since then has served as a vital resource for climate, environmental, ecosystem, and engineering research and training at the U. Maine, across the state of Maine and beyond. The routine use and primary support of the Facility come from the Principal Investigators and their collaborators that group under three research areas: glaciochemistry and climate/environmental reconstruction; paleoceanography and marine biogeochemistry; and environmental sensor development and material science engineering. The U. Maine is the State?s Land & Sea Grant university and only PhD granting institution, so the campus is the de facto academic research and research training hub of the state of Maine. The proposed advances of this research & training instrumentation will immediately impact current and future NSF-funded research projects that support extensive national and international collaborations. Specific to this proposal are collaborations with the University of Venice (Italy) and the University of Cambridge/British Antarctic Survey to develop laser ablation ICP-MS imaging of ice cores, and collaborations with New Zealand, Swiss, Chinese, Canadian, and Brazilian colleagues to analyze ice, thereby maintaining our leadership role in global ice core and climate change research. Likewise, the enhanced carbonate analysis capacity of the Element XR will have an immediate impact on NSF-funded research projects in the Gulf of Maine and in the South Pacific. The proposed instrumentation will facilitate new and important collaborations between academic colleges (College of Natural Science, Forestry, and Agriculture and the College of Engineering) and research units - the CCI and the Frontier Institute for Research in Sensor Technology - across the campus, as well as enabling new and broader scientific collaborations with other academic and scientific institutions across Maine.
The Ross Sea Region Marine Protected Area (RSRMPA), one of the world?s largest MPAs, encompasses one of the healthiest marine ecosystems remaining on this planet; however, it is exposed to increasing stress from ongoing climate change and fishing pressure. Numerous gaps in our understanding of the highly coupled nature of the Ross Sea marine ecosystem need to be addressed to support conservation efforts in the Ross Sea region, including informing the efficacy and management of the RSRMPA into the coming decades. The overarching goal of this research is to formulate an innovative and sustainable world-class research program aimed at better understanding, conserving, and managing the RSRMPA through the coordination of multi-faceted system-level approaches. There will be a coordinated effort to facilitate international collaboration; create education, outreach, and Diverse Equitable and Inclusive (DEI) opportunities; and increase conservation awareness. Coordinating Ross Sea marine ecosystem research will contribute to enhancing system-level global research, sustainable data networks, DEI, and climate equity. This program will also provide opportunity to develop similar frameworks for other large-scale, globally important systems. The trans-disciplinary aspiration can also serve to guide the NSF in sustaining or initiating new funding opportunities while addressing several of the 10 NSF BIG IDEAS and engaging multiple NSF Directorates. The project will help maintain NSF?s mission of scientific leadership by networking the Antarctic community by providing science-based conservation plans to help mitigate environmental changes in this pristine region of the Southern Ocean. The researchers will convene a workshop to strategize the implementation of an internationally networked, world class program that is based on inter- and trans-disciplinary approaches (including bridging science, cyberinfrastructure, policy, management, and conservation), while also providing opportunities for STEM education, early career development, and core DEI principles. To effectively facilitate the prioritization of research related to the regional and global interconnectedness of the Ross Sea marine ecosystem, the workshop will involve leading experts in Ross Sea marine research and other researchers, stakeholders, and policy experts involved in the greater oceanographic, climate and ecosystem/food web modeling communities. The workshop will determine a long-term decadal plan comprising the following phases: (1) initial data synthesis and ecosystem/food web model development; (2) field observations and modeling, networked through an internationally coordinated Ross Sea Observing System; and (3) data synthesis and modeling, including a ?sunset? plan to support ongoing RSRMPA management and preservation of the Ross Sea marine ecosystem. Outcomes will include a workshop report detailing the long-term research plan, a peer-reviewed article, educational and outreach materials, and a list of proposed research topics for implementing a world class research program and Principal Investigators who will help coordinate the multiple efforts aimed at addressing major gaps in our knowledge of the Ross Sea system.
Part I, Non-technical Abstract <br/>Concerns that the West Antarctic Ice Sheet (WAIS) might be susceptible to releasing its ice as giant icebergs into the Southern Ocean due to a warming climate, raising global sea level, were first expressed more than 40 years ago. To best-assess this threat, scientists need to know whether such events occurred in the geologically recent past, during warm intervals of past glacial-interglacial cycles. Ocean drilling near the most vulnerable sector of the WAIS, in 2019, yielded seafloor geologic records demonstrating times when icebergs dropped large volumes of sands and pebbles, called ice-rafted detritus (IRD) in deep water of the Amundsen Sea. Occurring together with IRD that was eroded from bedrock beneath the ice sheets, there are abundant microfossils of diatoms (algal plankton), which indicate high biological productivity in the open ocean. The new sediment cores provide a complete, uninterrupted record of a time of dramatic fluctuations of ice sheet extent that occurred over the last 3 million years. Therefore, they provide the means to obtain clear answers to the question whether ice sheet collapse occurred in the past and offering clues to its potential future. This project will investigate sediment intervals where IRD coincides with evidence of high diatom production, to test whether these two criteria indicate rapid ice sheet collapse. Geochemical analysis of IRD pebbles will help trace the source of the icebergs to likely on-land sites. By analyzing conditions of high diatom and IRD accumulation in deep ocean sediment, where local coastal influences can be avoided, we will assess oceanographic and climatic conditions associated with past ice sheet collapse events. Diatoms provide powerful evidence of temperature and ocean productivity changes in the past, that, when linked to time, can translate into rates of ice sheet drawdown. These results will provide critical data for designing, constraining and testing the next suite computer models that can determine the likelihood and timing of future ice sheet collapse in a warming world. The project will include training of undergraduate and graduate students from diverse backgrounds, and the public will be introduced to Antarctic science and engaged through several different outreach efforts.<br/><br/>Part 2, Technical Abstract<br/><br/>New drillcores from the Amundsen Sea, Antarctica (IODP Expedition 379) contain a continuous record of oceanographic changes and iceberg rafted debris (IRD) spanning the last 5 million years. This study aims to identify the signature of retreat/collapse of the West Antarctic Ice Sheet (WAIS) in these continental margin, deep-sea sediments by quantitatively analyzing, in detail, diatom and IRD records across glacial-interglacial lithostratigraphic transitions to establish the timing and frequency of Late Pliocene and Pleistocene WAIS collapse events. The investigators will secure age constraints and diagnostic observations of marine paleoenvironmental conditions for selected interglacial intervals of cores from sites U1532 and U1533, using high resolution micropaleontology of diatom assemblages coupled with microstratigraphic analysis of IRD depositional events, while petrography, geochronology and thermochronology of iceberg rafted clasts will provide evidence of iceberg sources and pathways. Depositional paleotemperatures will be assessed via a new paleotemperature proxy based on quantitative assessment of morphologic changes in the dominant Southern Ocean diatom Fragilariopsis kerguelensis. Their results will contribute to parameterization of new ice sheet models that seek to reconstruct and forecast West Antarctic Ice Sheet behavior. This project will directly contribute to undergraduate education at an undergraduate-only college and at a public university that serves a demographic typified by first generation university students and underrepresented groups. Spanning geology, geochemistry, sedimentology, paleontology and paleoceanography, the proposed work will allow undergraduate students to develop diverse skills through hands-on research within a collaborative team that is dedicated to societally relevant research. The two graduate students will conduct original research and work alongside/mentor undergraduates, making for a well-rounded research experience that prepares them for success in future academic or employment sectors. The discoveries that come from this deep-sea record from West Antarctica will be communicated by students and investigators at national and international conferences and an array of public science outreach events.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part 1: Nontechnical<br/> <br/>Unlike other locations on the globe Antarctica is not known for having large earthquakes and the remote nature and harsh conditions make it difficult to install and maintain seismometers for earthquake detection. Some researchers believe the lack of large earthquakes is due to the continent being surrounded by inactive tectonic margins. However, in the last two decades, scientists have discovered that more earthquakes occur in the interior of the continent than previously observed. This suggests that there are many earthquakes missing from historic earthquake catalogs. This study aims to find the missing earthquakes using novel earthquake detection and location techniques from seismic data collected from temporary and permanent seismic stations in Antarctica over the last 25 years. Locating these earthquakes will help understand if and where earthquakes are located in Antarctica and will help in planning future seismic deployments. As part of the project broader impacts, a field expedition with the Girls on Rock program will be conducted to teach high school age girls, and especially those from underrepresented backgrounds, data visualization techniques using scientific data. <br/> <br/>Part 2: Technical<br/> <br/>The spatial distribution of seismicity and the number of moderate magnitude earthquakes in Antarctica is not well-defined. The current catalog of earthquakes may be biased by uneven and sparse seismograph distribution on the continent. We will mine existing broadband seismic data from both permanent and temporary deployments to lower the earthquake detection threshold across Interior Antarctica, with a focus on tectonic earthquakes. The hypothesis is that Interior Antarctica has abundant moderate magnitude earthquakes, previously undetected. These earthquakes are likely collocated with major tectonic features such as the Transantarctic Mountains, the suspected Vostok collision zone, the West Antarctic Rift System, the crustal compositional boundary between East and West Antarctica, and the Cretaceous East Antarctic Rift. Previous seismic deployments have recorded earthquakes in the Antarctic interior, suggesting there are many earthquakes missing from the current catalog. We propose to use novel earthquake location techniques designed for automated detection and location using 25 years of continuous data archived at IRIS from PASSCAL experiments and permanent stations. The approach will use STA/LTA detectors on the first arrival P-wave to 90 degrees distance, Reverse Time Imaging to locate events, and beamforming at dense arrays strategically located on cratons for enhanced detection and location. The combination of detection and location techniques used in this work has not been used on teleseismic body waves, although similar methods have worked well for surface wave studies. If successful the project would provide an excellent training dataset for future scrutiny of newly discovered Antarctic seismicity with machine learning approaches and/or new targeted data collection. We plan to collaborate with Girls on Rock, a local and international organization committed to building a culturally diverse community in science, art, and wilderness exploration, in a summer field expedition and integrating computer coding into post-field scientific projects.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The evolution of surface and shallow subsurface meltwater across Antarctic ice shelves has important implications for their (in)stability, as demonstrated by the 2002 rapid collapse of the Larsen B Ice Shelf. It is vital to understand the causes of ice-shelf (in)stability because ice shelves buttress against the discharge of inland ice and therefore influence ice-sheet contributions to sea-level rise. Ice-shelf break-up may be triggered by stress variations associated with surface meltwater movement, ponding, and drainage. These variations may cause an ice shelf to flex and fracture. This four-year project will provide key geophysical observations to improve understanding of ice-shelf meltwater and its effects on (in)stability. The work will be conducted on the George VI Ice Shelf on the Antarctic Peninsula, where hundreds of surface lakes form each summer. <br/><br/>Over a 27-month period, global positioning systems, seismometers, water pressure transducers, automatic weather stations, and in-ice thermistor strings will be deployed to record ice shelf flexure, fracture seismicity, water depths, and surface and subsurface melting, respectively, in and around several surface lakes on the George VI Ice Shelf, within roughly 20 km of the British Antarctic Survey's Fossil Bluff Station. Field data will be used to validate and extend the team's approach to modelling ice-shelf flexure and stress, and possible "Larsen-B style" ice-shelf instability and break-up.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This project on emperor penguin populations will quantify penguin presence/absence, and colony size and trajectory, across the entire Antarctic continent using high-resolution satellite imagery. For a subset of the colonies, population estimates derived from high-resolution satellite images will be compared with those determined by aerial surveys - these results have been uploaded to MAPPPD (penguinmap.com) and are freely available for use. This validated information will be used to determine population estimates for all emperor penguin colonies through iterations of supervised classification and maximum likelihood calculations on the high-resolution imagery. The effect of spatial, geophysical, and environmental variables on population size and decadal-scale trends will be assessed using generalized linear models. This research will result in a first ever empirical result for emperor penguin population trends and habitat suitability, and will leverage currently-funded NSF infrastructure and hosting sites to publish results in near-real time to the public.
General Description:<br/>This project is intended to reveal the magma source regions, staging areas, and eruptive pathways within the active volcano Mount Erebus. This volcano is an end-member type known as phonolitic, which refers to the lava composition, and is almost purely carbon-dioxide-bearing and occurs in continental rift settings. It is in contrast to the better known water-bearing volcanoes which occur at plate boundary settings (such as Mount St Helens or Mount Fuji). Phonolitic volcanic eruptions elsewhere such as Tamboro or Vesuvius have caused more than 50,000 eruption related fatalities. Phonolites are also associated with rare earth element deposits, giving them economic interest. To illuminate the inner workings of Mount Erebus, we will cover the volcano with a dense network of geophysical probes based on magnetotelluric (MT) measurements. MT makes use of naturally occurring electromagnetic (EM) waves generated mainly by the sun as sources to provide images of the electrical conductivity structure of the Earth's interior. Conductivity is sensitive to the presence of fluids and melts in the Earth and so is well suited to understanding volcanic processes. The project is a cooperative effort between scientists from the United States, New Zealand, Japan and Canada. It implements new technology developed by the lead investigator and associates that allows such measurements to be taken on snow-covered terrains. This has applicability for frozen environments generally, such as resource exploration in the Arctic. The project supports a new post-doctoral researcher, and leverages imaging and measurement methods developed through support by other agencies and interfaced with commercial platforms.<br/><br/>Technical Description:<br/>The investigators propose to test magmatic evolution models for Mount Erebus volcano, Antarctica, using the magnetotelluric (MT) method. The phonolite lava flow compositions on Mount Erebus are uncommon, but provide a window into the range of upper mantle source compositions and melt differentiation paths. Explosive phonolite eruptions have been known worldwide for devastating eruptions such as Tambora and Vesuvius, and commonly host rare earth element deposits. In the MT method, temporal variations in the Earth's natural electromagnetic (EM) field are used as source fields to probe the electrical resistivity structure in the depth range of 1 to 100 kilometers. This effort will consist of approximately 100 MT sites, with some concentration in the summit area. Field acquisition will take place over two field seasons. The main goals are to 1) confirm the existence and the geometry of the uppermost magma chamber thought to reside at 5-10 kilometer depths; 2) attempt to identify, in the deeper resistivity structure, the magma staging area near the crust-mantle boundary; 3) image the steep, crustal-scale, near-vertical conduit carrying magma from the mantle; 4) infer the physical and chemical state from geophysical properties of a CO2-dominated mafic shield volcano; and 5) constrain the relationships between structural and magmatic/ hydrothermal activity related to the Terror Rift. Tomographic imaging of the interior resistivity will be performed using a new inversion platform developed at Utah, based on the deformable edge finite element method, that is the best available for accommodating the steep topography of the study area. The project is an international cooperation between University of Utah, GNS Science Wellington New Zealand (G. Hill, Co-I), and Tokyo Institute of Technology Japan (Y. Ogawa, Co-I), plus participation by University of Alberta (M. Unsworth) and Missouri State University (K. Mickus). Instrument deployments will be made exclusively by helicopter. The project implements new technology that allows MT measurements to be taken on snow-covered terrains. The project supports a new post-doctoral researcher, and leverages imaging and measurement methods developed through support by other agencies and interfaced with commercial platforms.
In this iteration of the McMurdo LTER project (MCM6), the project team will test ecological connectivity and stability theory in a system subject to strong physical drivers (geological legacies, extreme seasonality, and contemporary climate change) and driven by microbial organisms. Since microorganisms regulate most of the world's critical biogeochemical functions, these insights will be relevant far beyond polar ecosystems and will inform understanding and expectations of how natural and managed ecosystems respond to ongoing anthropogenic global change. MCM6 builds on previous foundational research, both in Antarctica and within the LTER network, to consider the temporal aspects of connectivity and how it relates to ecosystem stability. The project will examine how changes in the temporal variability of ecological connectivity interact with the legacies of the existing landscape that have defined habitats and biogeochemical cycling for millennia. The project team hypothesizes that the structure and functioning of the MDV ecosystem is dependent upon legacies and the contemporary frequency, duration, and magnitude of ecological connectivity. This hypothesis will be tested with new and continuing monitoring, experiments, and analyses of long-term datasets to examine: 1) the stability of these ecosystems as reflected by sentinel taxa, 2) the relationship between ecological legacies and ecosystem resilience, 3) the importance of material carryover during periods of low connectivity to maintaining biological activity and community stability, and 4) how changes in disturbance dynamics disrupt ecological cycles through the polar night. Tests of these hypotheses will occur in field and modeling activities using new and long-term datasets already collected. New datasets resulting from field activities will be made freely available via widely-known online databases (MCM LTER and EDI). The project team has also developed six Antarctic Core Ideas that encompass themes from data literacy to polar food webs and form a consistent thread across the education and outreach activities. Building on past success, collaborations will be established with teachers and artists embedded within the science teams, who will work to develop educational modules with science content informed by direct experience and artistic expression. Undergraduate mentoring efforts will incorporate computational methods through a new data-intensive scientific training program for MCM REU students. The project will also establish an Antarctic Research Experience for Community College Students at CU Boulder, to provide an immersive educational and research experience for students from diverse backgrounds in community colleges. MCM LTER will continue its mission of training and mentoring students, postdocs, and early career scientists as the next generation of leaders in polar ecosystem science and stewardship. Historically underrepresented participation will be expanded at each level of the project. To aid in these efforts, the project has established Education & Outreach and Diversity, Equity, and Inclusion committees to lead, coordinate, support, and integrate these activities through all aspects of MCM6.
The Antarctic Automatic Weather Station (AWS) network, first commenced in 1978, is the most extensive meteorological observing system on the Antarctic continent, approaching its 30th year at many of its key sites. Its prime focus as a long term observational record is vital to the measurement of the near surface climatology of the Antarctic atmosphere. AWS units measure air-temperature, pressure, wind speed and direction at a nominal surface height of 3m. Other parameters such as relative humidity and snow accumulation may also be taken. Observational data from the AWS are collected via the DCS Argos system aboard either NOAA or MetOp polar orbiting satellites and thus made available globally, in near real time via the GTS (Global Telecommunications System), to operational and synoptic weather forecasters. The surface observations from the AWS network also are often used to check on satellite and remote sensing observations, and the simulations of Global Climate Models (GCMs). Research instances of its use in this project include continued development of the climatology of the Antarctic atmosphere and surface wind studies of the Ross Ice Shelf. The AWS observations benefit the broader earth system science community, supporting research activities ranging from paleoclimate studies to penguin phenology.
The Antarctic Automatic Weather Station (AWS) program is a long-term automated surface weather observing network measuring key standard meteorological parameters, including temperature, humidity, wind speed and direction, barometric pressure, solar radiation, and snow accumulation. Observations from the network support weather forecasting, science research, and educational activities, and all data collected are made available to the public. This project will continue to maintain and operate the existing network. These data provide some of the only available weather observations in this very remote portion of the Earth. To ensure fidelity, observations are reviewed and checked for errors by a combination of automated methods and expert review, enabling the data to be used in a wide range of research areas. The project will be overseen by a team of scientists, researchers, and students, and a newly created AWS Advisory Board will provide independent input and guidance.
The activities for this project will be focused on the continued operation of the AWS network, establishment of an AWS Advisory Board, student engagement and outreach activities. This project will continue to maintain the AWS systems while upgrading the real-time processing of meteorological data from the AWS network. The team will continue to adapt to changes communication methods to ensure that data is distributed widely and in a timely manner. Prior NSF investments in the Polar Climate and Weather Station (PCWS) are leveraged to develop a robust production version that can be reliably used year-round in Antarctica. AWS observations will be quality-controlled and placed into a database where the public will be able to search and select subsets of observations. To resolve conflicting radiation shield setups for temperature observations, the team plans to test different radiation shields (with and without aspiration) deployed for one year at South Pole Station. The project will be advised by an independent group of diverse peers through a newly developed AWS Advisory Board. The team will incorporate students from all levels in all aspects of the project, including in the research design, engineering and productions of the PCWS, and in field deployments. A concerted effort to engage the public will be undertaken via scaled-up interactions with television meteorologists from several states across the US to bring Antarctica to the public.
1. A non-technical explanation of the project's broader significance and importance, that serves as a public justification for NSF funding. This part should be understandable to an educated reader who is not a scientist or engineer.
Katabatic or drainage winds, carry high-density air from a higher elevation down a slope under the force of gravity. Although katabatic flows are ubiquitous in alpine and polar regions, a surface-layer similarity theory is currently lacking for these flows, undermining the accuracy of numerical weather and climate prediction models. This project is interdisciplinary, and will give graduate and undergraduate students valuable experience interacting with researchers outside their core discipline. Furthermore, this project will broaden participating in science through recruitment of students from under-represented groups at OU and CU through established programs.
The Antarctic Ice Sheet drives many processes in the Earth system through its modulation of regional and global atmospheric and oceanic circulations, storage of fresh water, and effects on global albedo and climate. An understanding of the surface mass balance of the ice sheets is critical for predicting future sea level rise and for interpreting ice core records. Yet, the evolution of the ice sheets through snow deposition, erosion, and transport in katabatic winds (which are persistent across much of the Antarctic) remains poorly understood due to the lack of an overarching theoretical framework, scarcity of in situ observational datasets, and a lack of accurate numerical modeling tools. Advances in the fundamental understanding and modeling capabilities of katabatic transport processes are urgently needed in view of the future climatic and snowfall changes that are projected to occur within the Antarctic continent. This project will leverage the expertise of a multidisciplinary team of investigators (with backgrounds spanning cryospheric science, environmental fluid mechanics, and atmospheric science) to address these knowledge gaps.
2. A technical description of the project that states the problem to be studied, the goals and scope of the research, and the methods and approaches to be used. In many cases, the technical project description may be a modified version of the project summary submitted with the proposal.
Using field observations and direct numerical simulations of katabatic flow, this project is expected--- for the first time---to lead to a surface-layer similarity theory for katabatic flows relating turbulent fluxes to mean vertical gradients. The similarity theory will be used to develop surface boundary conditions for large eddy simulations (LES), enabling the first accurate LES of katabatic flow.
The numerical tools that the PIs will develop will allow them to investigate how the partitioning between snow redistribution, transport, and sublimation depends on the environmental parameters typically encountered in Antarctica (e.g. atmospheric stratification, surface sloping angles, and humidity profiles), and to develop simple models to infer snow transport based on satellite remote sensing and regional climate models
This award reflects the NSF statutory mission and has been deemed worthy of support through evaluation using the intellectual merit of the Foundation and broader impacts review criteria.
PUBLIC ABSTRACT – NSF 2231558/2231559
COLLABORATIVE RESEARCH: CONFERENCE: INTERDISCIPLINARY ANTARCTIC EARTH SCIENCE CONFERENCE & DEEP-FIELD PLANNING WORKSHOP
The unique Antarctic environment offers insight into processes and records not seen anywhere else on Earth, and is critical to understanding our planet’s history and future. The remoteness and logistics of Antarctic science brings together researchers from diverse disciplines who otherwise wouldn’t be presented with opportunities for collaboration, and often rarely attend the same academic conferences. The Interdisciplinary Antarctic Earth Science (IAES) conference is a biennial gathering that supports the collaboration of U.S. bio-, cryo-, geo-, and atmospheric science researchers working in the Antarctic. This proposal will support the next two IAES conferences to be held in 2022 and 2024, as well as a paired deep-field camp planning workshop. The IAES conference is important to the mission of the NSF in supporting interdisciplinary collaboration in the Antarctic earth sciences, but also fulfills recommendations by the National Academy for improving awareness, data sharing, and early career researcher mentoring and development. The size and scope of the IAES conference allow it to serve as a hub for novel, interdisciplinary collaboration, as well as an incubator for the development of the next generation of Antarctic earth scientists.
The goals of the IAES conference are to develop and deepen scientific collaborations across the Antarctic earth science community, and create a framework for future deep-field, as well as non-field-based research. The conference will share science through presentations of current research and keynote talks, broaden participation through welcoming new researchers from under-represented communities and disciplines, and deepen collaboration through interdisciplinary networking highlighting potential research connections, novel mentorship activities, and promoting data re-use, and application of remote sensing and modeling. Discussions resulting from the IAES conference will be used to develop white papers on future Antarctic collaborative research and deep-field camps based on community-driven research priorities. Community surveys and feedback will be solicited throughout the project to guide the future development of the IAES conference.
The seaward motion of ice sheets and glaciers is primarily controlled by basal sliding below, and internal viscous flow within, ice masses. The latter of these—viscous flow—is dependent on various factors, including temperature, stress, grain size, and the alignment of ice crystals during flow to produce a crystal orientation fabric (COF). Historically, ice flow has been modeled using a constitutive equation, termed “Glen’s law”, that describes ice flow rate as a function of temperature and stress. Glen’s law was constrained under relatively high-stress conditions, and is often attributed to the motion of crystal defects within ice grains. More recently, however, grain boundary sliding (GBS) has been invoked as the rate-controlling process under low-stress, “superplastic” conditions. The grain boundary sliding hypothesis is contentious because GBS is not thought to produce a COF, whereas geophysical measurements and polar ice cores demonstrate strong COFs in polar ice masses. However, very few COF measurements have been conducted on ice samples subjected to superplastic flow conditions in the laboratory. In this project, the PI primarily seeks to measure the evolution of ice COF across the transition from superplastic to Glen-type creep. Results will be used to interrogate the role of superplastic GBS creep within polar ice masses, and thereby provide constraints on polar ice discharge models.
Polycrystalline ice samples with grain sizes ranging from 5 µm to 1000 µm will be fabricated and deformed in the PI’s laboratory at WHOI, using a 1-atm cryogenic axial-torsion apparatus. Experiments will be conducted at temperatures of −30°C to −10°C, and at a constant uniaxial strain rate of 10-7 s-1. Under these conditions, 5% to 99.99% of strain should be accommodated by superplastic, GBS-limited creep, depending on the sample grain size. The deformed samples will then be imaged using cryogenic electron backscatter diffraction (cryo-EBSD) and high-angular-resolution electron backscatter diffraction (HR-EBSD) to quantify COF, grain size, grain shape, and crystal defect (dislocation) densities, among other microstructural properties. These measurements will be used to decipher the rate-controlling mechanisms operating within different thermomechanical regimes, and resolve a long-standing debate over whether superplastic creep can produce a COF in ice. In addition to the polycrystal experiments, ice bicrystals will be fabricated and deformed to investigate the micromechanical behavior of individual grain boundaries under superplastic conditions. Ultimately, these results will be used to provide a microstructural toolbox for identifying superplastic creep using geophysical (e.g., seismic, radar) and glaciological (e.g., ice core) observations. This project will support one graduate student within the MIT-WHOI Joint Program, one or more undergraduate summer students, and a junior faculty member (the PI). In addition, the PI will host a workshop aimed at bringing together experimentalists, glaciologists, and ice modelers to facilitate cross-disciplinary knowledge sharing and collaborative problem solving.
The aims of this CAREER proposal are to gain a greater understanding of the role of sympagic algae in Antarctic marine ecosystems with the goal to better parameterize their role in biogeochemical and ecosystem processes across dynamic environments. Specifically, this proposal will apply a laboratory-scale, ice-tank system that recreates the seasonal cycle of sea ice in the laboratory for the purpose of studying sympagic microbes to study the following questions:
1.1 Starting with a late autumn, mixed phytoplankton community, how do different algal species specialize to sea ice, seawater and flooded snow/ice habitats over winter?
1.2 What are the relationships between different methods of measuring primary production (fluorescence, O2 production, CO2 drawdown) in sea ice? Does this differ from seawater?
1.3 Does the presence of sea-ice algae influence the physical structure of sea ice?
1.4 How does the release of compatible solutes from algae during ice melt influence the dissolved organic pool?
In addition, I propose to integrate educational activities with my research goals. This includes development of an educational program at the university and K-12 level on Antarctic Sciences that develops critical thinking and quantitative skills, encourages STEM participation from underrepresented groups and establishes an interactive network of Antarctic researchers to broaden research opportunities.
The potential for future sea level rise from melting and collapse of Antarctic ice sheets and glaciers is concerning. We can improve our understanding of how water is exchanged between Antarctic ice sheets and the ocean by studying how ice sheets behaved in past climates, especially conditions that were similar to or warmer than those at present. For this project, the research team will document Antarctica's response across an interval when Earth transitioned from the warm Pliocene into the Pleistocene ice ages by combining marine and land evidence for glacier variations from sites near the Antarctic Peninsula, complimented by detailed work on timescales and fossil evidence for environmental change. An important goal is to test whether Antarctica's glaciers changed at the same time as glaciers in the Northern Hemisphere as Earth's most recent Ice Age intensified, or alternatively responded to regional climate forcing in the Southern Hemisphere. Eleven investigators from seven US institutions, as well as Argentine collaborators, will study new sediment cores from the International Ocean Discovery Program, as well as legacy cores from that program and on-land outcrops on James Ross Island. The group embraces a vertically integrated research program that allows high school, undergraduate, graduate, post-docs and faculty to work together on the same projects. This structure leverages the benefits of near-peer mentoring and the development of a robust collaborative research network while allowing all participants to take ownership of different parts of the project. All members of the team are firmly committed to attracting researchers from under-represented groups and will do this through existing channels as well as via co-creating programming that centers the perspectives of diverse students in conversations about sea-level rise and climate change.
The proposed research seeks to understand phasing between Northern and Southern Hemisphere glacier and climate changes, as a means to understand drivers and teleconnections. The dynamics of past Antarctic glaciation can be studied using the unique isotope geochemical and mineralogic fingerprints from glacial sectors tied to a well-constrained time model for the stratigraphic successions. The proposed work would further refine the stratigraphic context through coupled biostratigraphic and magnetostratigraphic work. The magnitude of iceberg calving and paths of icebergs will be revealed using the flux, geochemical and mineralogic signatures, and 40Ar/39Ar and U-Pb geochronology of ice-rafted detritus. These provenance tracers will establish which sectors of Antarctica's ice sheets are more vulnerable to collapse, and the timing and pacing of these events will be revealed by their stratigraphic context. Additionally, the team will work with Argentine collaborators to connect the marine and terrestrial records by studying glacier records intercalated with volcanic flows on James Ross Island. These new constraints will be integrated with a state of the art ice-sheet model to link changes in ice dynamics with their underlying causes. Together, these tight stratigraphic constraints, geochemical signatures, and ice-sheet model simulations will provide a means to compare to the global records of climate change, understand their primary drivers, and elucidate the role of the Antarctic ice sheet in a major, global climatic shift from the Pliocene into the Pleistocene.
Iceberg calving is a complex natural fracture process and a dominant cause of mass loss from the floating ice shelves on the margins of the Antarctic ice sheet. There is concern that rapid changes at these ice shelves can destabilize parts of the ice sheet and accelerate their contribution to sea-level rise. The goal of this project is to understand and simulate the fracture mechanics of calving and to develop physically-consistent calving schemes for ice-sheet models. This would enable more reliable estimation of Antarctic mass loss by reducing the uncertainty in projections. The research plan is integrated with an education and outreach plan that aims to (1) enhance computational modeling skills of engineering and Earth science students through a cross-college course and a high-performance computing workshop and (2) increase participation and diversity in engineering and sciences by providing interdisciplinary research opportunities to undergraduates and by deploying new cyberlearning tools to engage local K-12 students in the Metro Nashville Public Schools in computational science and engineering, and glaciology.<br/><br/>This project aims to provide fundamental understanding of iceberg calving by advancing the frontiers in computational fracture mechanics and nonlinear continuum mechanics and translating it to glaciology. The project investigates crevasse propagation using poro-damage mechanics models for hydrofracture that are consistent with nonlinear viscous ice rheology, along with the thermodynamics of refreezing in narrow crevasses at meter length scales. It will develop a fracture-physics based scheme to better represent calving in ice-sheet models using a multiscale method. The effort will also address research questions related to calving behavior of floating ice shelves and glaciers, with the goal of enabling more reliable prediction of calving fronts in whole-Antarctic ice-sheet simulations over decadal-to-millennial time scales.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Melting of snow and ice at the surface of the Antarctic ice sheet can lead to the formation of meltwater lakes, an important precursor to ice-shelf collapse and accelerated ice-sheet mass loss. Understanding the present state of Antarctic surface melt provides a baseline to gauge how quickly melt impacts could evolve in the future and to reduce uncertainties in estimates of future sea-level rise.
This project used a suite of complimentary measurements from Earth-observing satellites, ground observations, and numerical climate models to enhance understanding of surface melt and lakes, as well as the processes linking these systems. The project supported the scientific training of a postdoctoral associate, a graduate student, and several undergraduate researchers. In addition, the project aimed to promote public scientific literacy and the broadening of quantitative skills for high-school students through the development and implementation of an educational unit in a partnership with an education and outreach expert and two high school teachers.
We identified that surface lake drainages on East Antarctica’s Amery Ice Shelf closely correspond to peaks in the daily amplitude of ocean tides. This research indicates that tidal-induced flexure inherent to the ice shelf grounding zone when combined with sufficient surface meltwater volumes can trigger ice shelf surface lake drainages (Trusel et al., 2022). In addition, we developed new estimates of surface melting across the Antarctic ice sheet using satellite and reanalysis data. First, we developed and implemented a pan-Antarctic ice sheet surface melt detection method applied to C-band Advanced Scatterometer (ASCAT) radar backscatter data. These binary melt presence/absence data were then combined with radar backscatter and ERA5 reanalysis outputs to estimate daily rates of surface meltwater production (in mm of water equivalence) across the Antarctic Peninsula region. These data therefore provide a new, observationally based dataset to investigate the intensity and drivers of surface melting in Antarctica’s highest-melt region, and with which to evaluate climate model simulations. This method and an assessment of the resulting data are the subject of a forthcoming manuscript.
This research project is a multidisciplinary effort that brings together a diverse team of scientists from multiple institutions together to understand the foraging behavior and physiology of leopard seals and their role in the Southern Ocean food web. The project will examine the physiology and behavior of leopard seals to in an effort to determine their ability to respond to potential changes in their habitat and foraging areas. Using satellite tracking devices the team will examine the movement and diving behavior of leopard seals and couple this information with measurements of their physiological capacity. The project will determine whether leopard seals- who feed on diverse range of prey- are built differently than their deep diving relatives the Weddell and elephant seal who feed on fish and squid. The team will also determine whether leopard seals are operating at or near their physiological capability to determine how much, if any, ?reserve capacity? they might have to forage and live in changing environments. A better understanding of their home ranges, movement patterns, and general behavior will also be informative to help in managing human-leopard seal interactions. The highly visual nature of the data and analysis for this project lends itself to public and educational display and outreach, particularly as they relate to the changing Antarctic habitats. The project will use the research results to educate the public on the unique physiological and ecological adaptations to extreme environments seen in diving marine mammals, including adaptations to exercise under low oxygen conditions and energy utilization, which affect and dictate the lifestyle of these exceptional organisms. The results of the project will also contribute to the broader understanding that may enhance the aims of managing marine living resources.<br/><br/>The leopard seal is an apex predator in the Antarctic ecosystem. This project seeks to better understand the ability of the leopard seal to cope with a changing environment. The project will first examine the foraging behavior and habitat utilization of leopard seals using satellite telemetry. Specifically, satellite telemetry tags will be used to obtain dive profiles and movement data for individuals across multiple years. Diet and trophic level positions across multiple temporal scales will then be determined from physiological samples (e.g., blood, vibrissae, blubber fatty acids, stable isotopes, fecal matter). Oceanographic data will be integrated with these measures to develop habitat models that will be used to assess habitat type, habitat utilization, habitat preference, and home range areas for individual animals. Diet composition for individual seals will be evaluated to determine whether specific animals are generalists or specialists. Second, the team will investigate the physiological adaptations that allow leopard seals to be apex predators and determine to what extent leopard seals are working at or near their physiological limit. Diving behavior and physiology of leopard seals will be evaluated (for instance the aerobic dive limit for individual animals and skeletal muscle adaptations will be determined for diving under hypoxic conditions). Data from time-depth recorders will be used to determine foraging strategies for individual seals, and these diving characteristics will be related to physiological variables (e.g., blood volume, muscle oxygen stores) to better understand the link between foraging behavior and physiology. The team will compare myoglobin storage in swimming muscles associated with both forelimb and hind limb propulsion and the use of anaerobic versus aerobic metabolic systems while foraging.
Varsani, Arvind; Porazinska, Dorota; Schmidt, Steven; Bergstrom, Anna
No dataset link provided
Cryoconite holes are sediment-filled melt holes in the surface of glaciers that can be important sites of active microbial life in an otherwise mostly frozen and barren landscape. Previous studies in the McMurdo Dry Valleys, Antarctica suggest that viral infections of microbes, and a general lack of fertilizers (i.e., nutrients), may be important factors shaping the development and functioning of microbial communities in cryoconite holes. The researchers propose an experimental approach to understand how nutrient limitation affects diversity (number of species) and overall abundance of microbes, and how the diversity and abundance of microbes in turn affects the diversity, abundance, and infection type of viruses that parasitize the microbes in cryoconite sediments. The researchers will use sediments previously collected from Antarctic glaciers that have varying concentrations of viruses and nutrients, to set up a nutrient-addition experiment to determine how nutrients affect microbial and viral population dynamics. The results will deepen our understanding of how microbial communities in general are shaped by nutrients and viruses and give new insights into the functioning of viruses in extremely cold environments. The researchers will publish their findings in scientific journals and will share their discoveries with K-12 students from rural schools in collaboration with the Pinhead Institute and will connect undergraduate students from under-represented minorities to polar research through participation in the universitys Science, Technology, Engineering & Mathematics Routes Uplift Research Program. Outreach will be achieved through videos produced and distributed by a professional science communicator. The research advances a National Science Foundation goal of expanding fundamental knowledge of Antarctic systems, biota, and processes by utilizing the unique characteristics of the Antarctic region as a science observing platform.
The Principal Investigators propose an experimental approach to understand how nutrient limitation affects microbial diversity and abundances and their cascading effects on virus diversity, abundance, and mode of infection (lysis vs. lysogeny) in Antarctic cryoconite holes. Cryoconite holes are ideal natural microcosms for manipulative studies, not available in other cryospheric ecosystems. The PIs will use previously collected cryoconite from across a gradient of both viral diversity and nutrient levels to address questions about key limiting nutrients and microbial-viral community dynamics in cryoconite sediments. Nutrient manipulation experiments will be conducted in a growth chamber that closely approximates the light and temperature regime of in situ cryoconite holes to test three core hypotheses: (1) phosphorus availability limits microbial productivity and abundance in cryoconite holes; (2) relaxing nutrient limitation in cryoconite from low-diversity glaciers will increase species diversity, leading microbial communities to resemble those found on more nutrient-rich glaciers; (3) relaxing nutrient limitation will increase the diversity and abundance of viruses by increasing the availability of suitable hosts, and decrease the prevalence of lysogenic infections. By manipulating nutrient limitation within a realistic range, this project will help verify hypothesized phosphorus limitation of Antarctic cryoconite holes and will extend understanding of the connections between nutrients, diversity, and viral infection dynamics in the cryosphere more generally. A better understanding of these dynamics in cryoconite sediments improves the ability of scientists to forecast future impacts of environmental changes in the cryosphere.
This award reflects NSF''s statutory mission and has been deemed worthy of support through evaluation using the Foundation''s intellectual merit and broader impacts review criteria.
Antarctic notothenioid fishes, also known as cryonotothenioids, inhabit the icy and highly oxygenated waters surrounding the Antarctic continent after diverging from notothenioids inhabiting more temperate waters. Notothenioid hemoglobin and blood parameters are known to have evolved along with the establishment of stable polar conditions, and among Antarctic notothenioids, icefishes are evolutionary oddities living without hemoglobin following the deletion of all functional hemoglobin genes from their genomes. In this project, we investigate the evolution of hemoglobin genes and gene clusters across the notothenioid radiation until their loss in the icefish ancestor after its divergence from the dragonfish lineage to understand the forces, mechanisms, and potential causes for hemoglobin gene loss in the icefish ancestor.
This project will develop methods to measure the ratios of carbon-13 to carbon-12, and heavy to light hydrogen in methane in air trapped in ice cores. The ratios of the different forms of carbon and hydrogen are "fingerprints" of different sources of this gas in the past--for example wetlands in the tropics versus methane frozen in the sea floor. Once the analysis method is developed, the measurements will be used to examine why methane changed abruptly in the past, both during the last ice age, and during previous warm periods. The data will be used to understand how methane sources like wildfires, methane hydrates, and wetlands respond to climate change. This information is needed to understand future risks of large changes in methane in the atmosphere as Earth warms. <br/><br/>The project involves two tasks. First, the investigators will build and test a gas extraction system for methane isotopic measurements using continuous flow methods, with the goal of equaling or bettering the precision attained by the few other laboratories that make these measurements. The system will be interfaced with existing mass spectrometers at Oregon State University. The system consists of a vacuum chamber and sequence of traps, purification columns, and furnaces that separate methane from other gases and convert it to carbon dioxide or hydrogen for mass spectrometry. Second, the team will measure the isotopic composition of methane across large changes in concentration associated with two past interglacial periods and during abrupt methane changes of the last ice age. These measurements will be used to understand if the main reason for these concentration changes is climate-driven changes in emissions from wetlands, or whether other sources are involved, for example methane hydrates or wildfires.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Not all of Antarctica is covered in ice. In fact, soils are common to many parts of Antarctica, and these soils are often unlike any others found on Earth. Antarctic soils harbor unique microorganisms able to cope with the extremely cold and dry conditions common to much of the continent. For decades, microbiologists have been drawn to the unique soils in Antarctica, yet critical knowledge gaps remain. Most notably, it is unclear what properties allow certain microbes to thrive in Antarctic soils. By using a range of methods, this project is developing comprehensive model that discovers the unique genomic features of soils diversity, distributions, and adaptations that allow Antarctic soil microbes to thrive in extreme environments. The proposed work will be relevant to researchers in many fields, including engineers seeking to develop new biotechnologies, ecologists studying the contributions of these microbial communities to the functioning of Antarctic ecosystems, microbiologists studying novel microbial adaptations to extreme environmental conditions, and even astrobiologists studying the potential for life on Mars. More generally, the proposed research presents an opportunity to advance our current understanding of the microbial life found in one of the more distinctive microbial habitats on Earth, a habitat that is inaccessible to many scientists and a habitat that is increasingly under threat from climate change.
The research project explores the microbial diversity in Antarctic soils and links specific features to different soil types and environmental conditions. The overarching questions include: What microbial taxa are found in a variety of Antarctic environments? What are the environmental preferences of specific taxa or lineages? What are the genomic and phenotypic traits of microorganisms that allow them to persist in extreme environments and determine biogeographical differneces? This project will analyze archived soils collected from across Antarctica by a network of international collaborators, with samples selected to span broad gradients in soil and site conditions. The project uses cultivation-independent, high-throughput genomic analysis methods and cultivation-dependent approaches to analyze bacterial and fungal communities in soil samples. The results will be used to predict the distributions of specific taxa and lineages, obtain genomic information for the more ubiquitous and abundant taxa, and quantify growth responses in vitro across gradients in temperature, moisture, and salinity. This integration of ecological, environmental, genomic, and trait-based information will provide a comprehensive understanding of microbial life in Antarctic soils. This project will also help facilitate new collaborations between scientists across the globe while providing undergraduate students with ''hands-on'' research experiences that introduce the next generation of scientists to the field of Antarctic biology.
This award reflects NSF''s statutory mission and has been deemed worthy of support through evaluation using the Foundation''s intellectual merit and broader impacts review criteria.
This project will develop a new ice-penetrating radar system that can simultaneously map glacier geometry and glacier flow along repeat profiles. Forecasting an ice-sheet’s contribution to sea level requires an estimate for the initial ice-sheet geometry and the parameters that govern ice flow and slip across bedrock. Existing ice-sheet models cannot independently determine this information from conventional observations of ice-surface velocities and glacier geometry. This introduces substantial uncertainty into simulations of past and future ice-sheet behavior. Thus, this new radar capability is conceived to provide the needed data to support higher-fidelity simulations of past and future ice-sheet behavior and more accurate projections of future sea level.
The new radar system will integrate two existing radars (the multi-channel coherent radio-echo depth sounder and the accumulation radar) developed by the Center for the Remote Sensing of Ice Sheets, as well as adding new capabilities. An eight-element very high frequency (VHF; 140-215 MHz) array will have sufficient cross-track aperture to swath map internal layers and the ice-sheet base in three dimensions. A single ultra high frequency (UHF; 600-900 MHz) antenna will have the range and phase resolution to map internal layer displacement with 0.25-mm precision. The VHF array will create 3D mappings of layer geometry that enable measurements of vertical velocities by accounting for spatial offsets between repeat profiles and changing surface conditions. The vertical displacement measurement will then be made by determining the difference in radar phase response recorded by the UHF antenna for radar profiles collected at the same locations at different times. The UHF antenna will be dual-polarized and thus capable of isolating both components of complex internal reflections. This should enable inferences of ice crystal orientation fabric and widespread mapping of ice viscosity. Initial field testing of the radar will occur on the McMurdo Ice Shelf and then progress to Thwaites Glacier, Antarctica. The dual-band radar system technology and processing algorithms will be developed with versatile extensible hardware and user-friendly software so that this system will serve as a prototype for a future community radar system.
The Antarctic Circumpolar Current (ACC) is the largest current on the planet, flowing west to east around Antarctica, forming a barrier that separates warmer waters to the north from colder waters to the south. Ocean eddies (like atmospheric storms) break through the ACC barrier, transferring heat across the ACC towards Antarctica. When warmer ocean waters intrude onto the Antarctic continental shelves, they contribute to glacial melt and ice shelf retreat. Over the past several decades, the Southern Ocean has warmed and winds have increased due to climate change. Somewhat surprisingly the ACC, though pushed by faster winds, has not accelerated; a faster current would present a stronger barrier to heat transfer. Instead, ocean eddies have increased. These eddies are concentrated at 6-7 "hot spots". Drake Passage is one of these hot spots. As the narrowest land gap on the entire circumpolar path of the ACC, Drake Passsage is an ideal monitoring spot. However, it is also one of the windiest and roughest stretches of water on the globe. The only ship that crosses Drake Passage year-round is the USAP supply vessel for Palmer Station, making it a unique platform to monitor the currents and temperature with a minimum of personnel and resources. The Drake Passage time series of upper ocean currents and temperature is now in its 24th year. The upper ocean temperature measurements have found significant warming in Drake Passage. The upper ocean current measurements have confirmed that the ACC has remained steady on average but have also revealed a complicated filamented current structure. Combining temperature and current measurements has provided a better understanding of heat transfer across the ACC by eddies. The time series has also provided valuable ground-truth for satellite measurements and for numerical model predictions looking at the entire ACC. Our studies are focused on examining low-frequency variability - seasonal, interannual, and decadal - in order to provide baselines from which to evaluate and interpret physical and biogeochemical changes occurring in the Southern Ocean.
The Southern Ocean plays a key role in modulating the global carbon cycle, but the size and even the sign of the flux of carbon dioxide between the ocean and atmosphere in this region is still uncertain. This is in part due to the lack of measurements in this remote region of the world ocean. This project continues a multi-year time series of shipboard chemical measurements in the Drake Passage to detect changes in the ocean carbon cycle and to improve the understanding of mechanisms driving natural variability and long-term change in the Southern Ocean. More specifically, this project is a continuation of the collection of underway upper ocean measurements of the surface partial pressure of carbon dioxide during crossings of the Drake Passage by the Antarctic Research and Supply Vessel Laurence M. Gould. This project also includes collection and analysis of discrete samples relevant to ocean carbon cycle studies including macronutrient concentrations, total carbon dioxide concentrations, and the carbon isotopic composition of total carbon dioxide. The Drake Passage data are made readily available to the international science community and serve as both validation and constraints of remotely sensed observations and numerical coupled earth systems models.
In this project we investigated glaciers that drain ice from the East Antarctic Ice Sheet through the Transantarctic Mountains into the present-day Ross Ice Shelf. The outlet glaciers that flow through the Transantarctic Mountains have thinned significantly over the past 15,000 years, especially as they retreated from Last Glacial Maximum highstands to their present-day grounding lines. At certain locations and for certain glaciers, rocks or bedrock have been sampled to provide constraints on the timing of when ice retreated from these locations. In the locations where geochronological data are available we can use these data as direct constraints on ice-flow models that simulate ice elevation change over time. The intellectual merit of this work is using ice-flow models to spatially and temporally extrapolate between these limited geochronological data points, which enables new understanding of glacier evolution.
The mountainous topography in this region is complex, and there are limited measurements of the topography beneath the ice of the Transantarctic outlet glaciers. Since the topography of the glacier bed is an important control on ice flow and is a necessary boundary condition in models we developed a new gridded bed product at Beardmore Glacier, the one location where sufficient data were available, and we compared this to continent-scale gridded bed products. We found that for this glacier, the BedMachine v1 product was reasonably similar to the Beardmore Glacier bed topography measurements; our limited evaluation suggests that the BedMachine product may be sufficient at other Transantarctic outlets where bed measurements are not available, but that other compilations of bed topography data that do not include information about ice flow directions do not provide reliable results. Using these data and available geochronological constraints we investigated Beardmore Glacier evolution since the Last Glacial Maximum using simplified (flowline) models of ice flow.
In addition to flowline modeling at Beardmore Glacier, we developed a flow-model setup using the open-source 'icepack' model that uses the shallow stream equations and resolves flow in both the x and y directions. The key value added over flowline (or parameterized flowband) models is that this can capture converging and diverging ice flow, variable side wall and bottom drag, and other geometric complexities. In these simulations we can evaluate the past accumulation, ice influx, and ice outflux to compare controls on deglaciation to data constraints on the chronology of deglaciation.
We also used a flowline model to investigate the Darwin-Hatherton Glacier System. Exposure ages and radiocarbon ages of glacial deposits at four locations alongside Hatherton and Darwin glaciers record several hundred meters of late Pleistocene to early Holocene thickening relative to present. Deglaciation was relatively complex at this site, and we also found that Byrd glacier likely contributed ice to the catchment of the Darwin-Hatherton glacier system during the last glacial maximum, and that subsequent convergent flow from Byrd and Mulock glaciers during deglaciation complicated the response of the Darwin-Hatherton system. These new insights can be used on their own to better understand local deglaciation, and can also be used to evaluate regional or continent-scale model calculations.
Separately, we investigated the general response of outlet glaciers to different sources of climate forcing. We found that outlet glaciers have a characteristically different response over time to surface-mass-balance forcing applied over the interior than to oceanic forcing applied at the grounding line. Our models demonstrated that ocean forcing first engages the fast, local response and then the slow adjustment of interior ice, whereas surface-mass-balance forcing is dominated by the slow interior adjustment. These insights contributed to our general understanding of how outlet glaciers may have evolved over time.
Our new model investigations provide a framework that can be applied at other Transantarctic outlet glaciers where geochronological data are available. In particular, our 'icepack' setup is an archived and documented resource for the community. These tools are available for future investigations, including additional investigations at Beardmore Glacier and at other Transantarctic Mountain outlet glaciers. Scientific broader impacts include that this contributes to our understanding of the past behavior of East Antarctic ice, which provides an important constraint on the future evolution of Antarctica. Our team has engaged in public outreach and has engaged students in this research. Two graduate students led in aspects of this work, and have since gone on to research positions after their PhD.
This research project is a multidisciplinary effort that brings together a diverse team of scientists from multiple institutions together to understand the foraging behavior and physiology of leopard seals and their role in the Southern Ocean food web. The project will examine the physiology and behavior of leopard seals to in an effort to determine their ability to respond to potential changes in their habitat and foraging areas. Using satellite tracking devices the team will examine the movement and diving behavior of leopard seals and couple this information with measurements of their physiological capacity. The project will determine whether leopard seals- who feed on diverse range of prey- are built differently than their deep diving relatives the Weddell and elephant seal who feed on fish and squid. The team will also determine whether leopard seals are operating at or near their physiological capability to determine how much, if any, ?reserve capacity? they might have to forage and live in changing environments. A better understanding of their home ranges, movement patterns, and general behavior will also be informative to help in managing human-leopard seal interactions. The highly visual nature of the data and analysis for this project lends itself to public and educational display and outreach, particularly as they relate to the changing Antarctic habitats. The project will use the research results to educate the public on the unique physiological and ecological adaptations to extreme environments seen in diving marine mammals, including adaptations to exercise under low oxygen conditions and energy utilization, which affect and dictate the lifestyle of these exceptional organisms. The results of the project will also contribute to the broader understanding that may enhance the aims of managing marine living resources.<br/>The leopard seal is an apex predator in the Antarctic ecosystem. This project seeks to better understand the ability of the leopard seal to cope with a changing environment. The project will first examine the foraging behavior and habitat utilization of leopard seals using satellite telemetry. Specifically, satellite telemetry tags will be used to obtain dive profiles and movement data for individuals across multiple years. Diet and trophic level positions across multiple temporal scales will then be determined from physiological samples (e.g., blood, vibrissae, blubber fatty acids, stable isotopes, fecal matter). Oceanographic data will be integrated with these measures to develop habitat models that will be used to assess habitat type, habitat utilization, habitat preference, and home range areas for individual animals. Diet composition for individual seals will be evaluated to determine whether specific animals are generalists or specialists. Second, the team will investigate the physiological adaptations that allow leopard seals to be apex predators and determine to what extent leopard seals are working at or near their physiological limit. Diving behavior and physiology of leopard seals will be evaluated (for instance the aerobic dive limit for individual animals and skeletal muscle adaptations will be determined for diving under hypoxic conditions). Data from time-depth recorders will be used to determine foraging strategies for individual seals, and these diving characteristics will be related to physiological variables (e.g., blood volume, muscle oxygen stores) to better understand the link between foraging behavior and physiology. The team will compare myoglobin storage in swimming muscles associated with both forelimb and hind limb propulsion and the use of anaerobic versus aerobic metabolic systems while foraging.
Current networking capacity at McMurdo Station is insufficient to even be considered broadband, with a summer population of up to 1000 people sharing what is equivalent to the connection enjoyed by a typical family of three in the United States. The changing Antarctic ice sheets and Southern Ocean are large, complex systems that require cutting edge technology to do cutting edge research, with remote technology becoming increasingly useful and even necessary to monitor changes at sufficient spatial and temporal scales. Antarctic science also often involves large data-transfer needs not currently met by existing satellite communication infrastructure. This workshop will gather representatives from across Antarctic science disciplinesfrom astronomy to zoologyas well as research and education networking experts to explore the scientific advances that would be enabled through dramatically increased real-time network connectivity, and also consider opportunities for subsea cable instrumentation.
This workshop will assess the importance of a subsea fiber optic cable for high-capacity real-time connectivity in the US Antarctic Program, which is at the forefront of some of the greatest climate-related challenges facing our planet. The workshop will: (1) document unmet or poorly met current scientific and logistic needs for connectivity; (2) explore connectivity needs for planned future research and note the scientific advances that would be possible if the full value of modern cyberinfrastructure-empowered research could be brought to the Antarctic research community; and (3) identify scientific opportunities in planning a fully instrumented communication cable as a scientific observatory. Due to the ongoing COVID-19 pandemic, the workshop will be hosted and streamed online. While the workshop will be limited to invited personnel in order to facilitate a collaborative working environment, broad community input will be sought via survey and via comment on draft outputs. A workshop summary document and report will be delivered to NSF. Increasing US Antarctic connectivity by orders of magnitude will be transformative for science and logistics, and it may well usher in a new era of Antarctic science that is more accessible, efficient and sustainable.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Stable isotope analyses of carbon and nitrogen (δ13C and δ15N) are commonly used to investigate animal migration, foraging locations and diet, especially in marine species that can travel over great distances. One other stable isotope, sulfur (δ34S), is not as commonly used but is increasingly being applied to refine and corroborate data obtained from carbon and nitrogen analyses. Collagen is one of the best tissues for these analyses as it is abundant in bone, preserves well, and can be easily extracted for analysis. In the Ross Sea region, the cold, dry environment has been conductive for the preservation of Adélie penguin (Pygoscelis adeliae) bones, feathers, eggshell and even mummified remains, at active and abandoned colonies that date from before the Last Glacial Maximum (>45,000 yrs ago) through the Holocene. Most of these colonies are associated with one of three polynyas, or highly productive areas of open water surrounded by sea ice in the Ross Sea. Thus, this species is an excellent bioindicator for marine conditions, past and present, and its colonies have appeared and disappeared throughout this region with changing climate and sea ice regimes for millennia. Current warming trends are inducing relatively rapid ecological responses by this species and some of the largest colonies in the Ross Sea are likely to be abandoned in the next 50 years from rising sea level. The recently established Ross Sea Marine Protected Area aims to protect Adélie penguins and other species in this region from human impacts and knowledge on how this species responds to climate change, past and present, will support this goal.
We propose to investigate ecological responses in diet and foraging behavior of the Adélie penguin to known climatic events that occurred in the middle to late Holocene, specifically, before, during and after a warming period known as the penguin ‘optimum’ at 2000 - 4000 cal yr before present (BP). We will apply for the first time a suite of three stable isotope analyses (δ13C, δ15N, δ34S) on chick bones and feathers, as well as prey remains, from active and abandoned colonies in the Ross Sea. We will use existing tissue samples (~60-80 bones) collected by PI Emslie with NSF support since 2001 and supplement these with newly collected samples of bones and feathers in this project. We will conduct compound-specific isotope analyses of carbon on essential amino acids from collagen from a selected sample of 30-40 bones that span the past 5000 yrs to provide corroboratory information. We will apply three-dimensional Bayesian niche models and/or community metrics using R scripts in these analyses to identify isotopic ‘signatures’ of existing and past foraging grounds and polynyas used by Adélie penguins in the southern, central, and northern Ross Sea. This four-year study will the first of its kind to apply multiple stable isotope analyses to investigate a living species of seabird over millennia in a region where it still exists today.
Broader Impacts:
The PIs are committed to public engagement and enhancement of K-12 education in the STEM sciences. Broader impacts of this research will include support and training for one Ph.D., two M.S., and eight undergraduate students in the Department of Biology and Marine Biology, and two M.A. students in the Watson School of Education at the University of North Carolina Wilmington (UNCW). The last two students will continue to expand on a detailed polar curriculum that was initiated in previous NSF grants for 2nd and 4th grade students, and most recently for 9-12th grade students now available on PI Emslie’s website (www.uncw.edu/penguins). Additional curricula for K-12 students will be designed and tested in this project, which will include visitation to local K-12 schools. As in previous awards, we will focus on schools that serve historically under-represented groups in the sciences. We will work with the UNCW Center for Education in STEM Sciences to assess the efficacy of this new curricula. All curricula will be uploaded on the Educational Resource Commons website. Field work will include blogs and active question-answer sessions with students at these schools. We will continue to post project information and updates on PI Emslie’s website and YouTube channel. Our partnership with tour ship companies will provide a platform for onboard lectures on the importance of scientific research as well as citizen science opportunities for another sector of the public. This proposal requires fieldwork in the Antarctic.
van der Veen, Cornelis; Stearns, Leigh; Paden, John
No dataset link provided
Van der Veen/1543530<br/><br/>The objective of this research is to gain better understanding of the West Antarctic ice flow in the transition region from grounded ice to floating ice shelves and investigate the conditions that can initiate and sustain major retreat of these glaciers. Several major Antarctic outlet glaciers and ice streams will be investigated using a suite of observational techniques and modeling tools. Glaciers include Thwaites Glacier, which has become a focal point in the discussion of West Antarctic retreat, Whillans Ice Stream as an example of the archetype ice stream, and Byrd Glacier, a major outlet glacier draining East Antarctica through the Transantarctic Mountains into the Ross Ice Shelf. This study will investigate whether the ongoing changes in these glaciers will lead to long-term mass loss (the onset of ice sheet collapse), or whether these glaciers will quickly stabilize with a new geometry. <br/><br/>To adequately incorporate the dynamic behavior of outlet glaciers and ice streams requires inclusion of the relevant physical processes, and the development of regional models that employ a numerical grid with a horizontal grid spacing sufficiently refined to capture smaller-scale bed topographic features that may control the flow of these glaciers. This award revisits the issue of stability of marine-terminating glaciers whose grounding line is located on a retrograded bed slope. In particular, an attempt will be made to resolve the question whether observed rapid changes are the result of perturbations at the terminus or grounding line, or whether these changes reflect ice-dynamical forcing over the grounded reaches. High-resolution satellite imagery will be used to investigate ice-flow perturbations on smaller spatial scales than has been done before, to evaluate the importance of localized sites of high basal resistance on grounding-line stability. This collaborative project involves a range of modeling strategies including force-budget analysis, flow-band modeling, Full Stokes modeling for local studies, and using the Ice Sheet System Model developed at JPL for regional modeling. Broader Impacts include training two graduate students in computer simulations and ice sheet modeling algorithms. The work will also expand on a web-based interactive flowline model, so that it includes more realistic grounding line dynamics.
Siddoway, Christine; Thomson, Stuart; Teyssier, Christian
No project link provided
in progress
No project link provided
in progress
Sediment records off the coast of Marie Byrd Land (MBL), Antarctica suggest frequent and dramatic changes in the size of the West Antarctic Ice Sheet (WAIS) over short (tens of thousands of years) and long (millions of years) time frames in the past. WAIS currently overrides much of MBL and covers the rugged and scoured bedrock landscape. The ice sheet carved narrow linear troughs that reach depths of two to three thousand meters below sea level as outlet glaciers flowed from the interior of the continent to the oceans. As a result, large volumes of fragmented continental bedrock were carried out to the seabed. The glaciers cut downward into a region of crystalline rocks (i.e. granite) that display a significant temperature change as a function of rock depth. The strong geothermal gradient in the bedrock is favorable for determining when the bedrock became exhumed, or "uncovered" by action of the overriding icesheet or other processes. Our approach takes advantage of a reference horizon, or paleogeotherm, established when high-T mineral thermochronometers across Marie Byrd Land (MBL) cooled from temperatures of >800° C to 300° C, due to rapid regional extension at ~100 Ma . The event imparted a signature through which the subsequent Cenozoic landscape history can be explored: MBL's elevated geothermal gradient, sustained during the Cenozoic, created favorable conditions for sensitive apatite and zircon low-T thermochronometers to record bedrock cooling related to glacial incision.
Analyzing the chemistry of minerals (zircon and apatite) within fragments of eroded rock will reveal the rate and timing of the bedrock erosion and development of topography in West Antarctica. This collaborative project addresses the following questions: When did the land become high enough for a large ice sheet to form? What was the regional pre-glacial topography? Under what climate conditions, and at what point in the growth of an ice sheet, did glaciers begin to cut sharply into bedrock to form the narrow troughs that flow seaward? The research will lead to greater understanding of past Antarctic ice sheet fluctuations and identify precise timing of glacial incisionm which will clarify the onset of WAIS glacier incision and assess the evolution of Cenozoic paleo-topography. The collaborative project provides training for one graduate and 8 undergraduate students in STEM. These students, together with PIs, will refine West Antarctic ice sheet history and obtain results that pertain to the international societal response to contemporary ice sheet change and its global consequences.
The methods used for the research include:
•Low-temperature (T) thermochronology and Pecube 3-D thermo-kinematic modeling, applied to the timing and characterizatio episodes of glacial erosional incision.
•Single-grain double- and triple-dating of zircon and apatite, to determine the detailed crustal thermal evolution of the region, enabling the research team to identify the comparative topographic influences on glaciation versus bedrock uplift induced by Eocene to present tectonism/magmatism.
Students and PIs employed state-of-the-art analytical facilities in Arizona and Minnesota, expanding the geo- and thermochronologic history of MBL from bedrock samples and offshore sedimentary deposits. The temperature and time data we acquired will provide constraints on paleotopography, isostasy, and the thermal evolution of MBL that will be modeled in 3D using Pecube model simulations. Within hot crust, less incision is required to expose bedrock containing the distinct thermochronometric profile; a prediction we are testing through use of inverse Pecube 3-D models of the thermal field through which bedrock and detrital samples cooled. Using results from Pecube, the ICI-Hot team will examine time-varying topography formed in response to changes in erosion rates, topographic relief, geothermal gradient and/or flexural isostatic rigidity. These effects are manifestations of dynamic processes in the WAIS, including ice sheet loading, ice volume fluctuations, relative motion upon crustal faults, and magmatism-related elevation increase across the MBL dome. The project makes use of pre-existing sample collections housed at the US Polar Rock Repository, IODP's Gulf Coast Core Repository, and the OSU Marine and Geology Repository. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Glacial ice cores serve as a museum back in time, providing detailed records of past climatic conditions. In addition to chronological records such as temperature, chemistry and gas composition, ice provides a unique environment for preserving microbes and other biological materials through time. These microbes provide invaluable insight into the physiological capabilities necessary for survival in the Earths cryosphere and other icy planetary bodies, yet little is known about them. This award supports fundamental research into the activity of microbes in ice, and directly supports major research priorities regarding Antarctic biota identified in the 2015 National Academies of Sciences, Engineering, and Medicine report, A Strategic Vision for NSF Investments in Antarctic and Southern Ocean Research. The broader impacts of this work are that it will be relevant to researchers across paleoclimate and biological fields. It will support two early career researchers, a graduate and an undergraduate student who will conduct laboratory analyses, participate in outreach activities, publish papers in scientific journals and present at conferences.
This work will use previously collected ice cores to investigate englacial microbial activity from the Holocene back to the Last Glacial Maximum from the blue ice area of Taylor Glacier, Antarctica. The proposal identified making significant contributions to 1) investing how Antarctic organisms evolve and adapt to changing environment, 2) understanding how microbes alter the preservation of paleorecord-relevant gas and trace element information in ice cores, and 3) identifying microbial life in cores and their activity in relation to dust depositional events. Two recently developed complementary techniques (bio-orthogonal noncanonical amino acid tagging and deuterium isotope probing) in combination with Raman Confocal Microspectroscopy will be used to assess and quantify microbial activity in ice. During phase one of the project, these methods will be optimized using deaccessioned ice cores available at the National Science Foundations Ice Core Facility. In phase two, ice cores in a time series from the Taylor Glacier will be analyzed for geochemistry and microbial activity. Research results will provide a comprehensive view of englacial microbial communities, including their metabolic diversity and activity, and the effect of geochemical parameters on microbial assemblages from different climate periods. Given the dearth of information available on englacial microbial communities, the results of this research will be of particular significance.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
As plate tectonics pushed Antarctica into a polar position, by ~34 million years ago, the continent and its surrounding Southern Ocean (SO) became geographically and thermally isolated by the Antarctic Circumpolar Current. Terrestrial and marine glaciation followed, resulting in extinctions as well as the survival and radiation of unique flora and fauna. The notothenioid fish survived and arose from a common ancestral stock into tax with 120 species that dominates today's SO fish fauna. The Notothenioids evolved adaptive traits including novel antifreeze proteins for survival in extreme cold, but also suffered seemingly adverse trait loss including red blood cells in the icefish family, and the ability to mount cellular responses to mitigate heat stress ? otherwise ubiquitous across all life. This project aims to understand how the notothenoid genomes have changed and contributed to their evolution in the cold. The project will sequence, analyze and compare the genomes of two strategic pairs of notothenioid fishes representing both red-blooded and white-blooded species. Each pair will consist of one Antarctic species and one that has readapted to the temperate waters of S. America or New Zealand. The project will also compare the Antarctic species genomes to a genome of the closet non-Antarctic relative representing the temperate notothenioid ancestor. The work aims to uncover the mechanisms that enabled the adaptive evolution of this ecologically vital group of fish in the freezing Southern Ocean, and shed light on their adaptability to a warming world. The finished genomes will be made available to promote and advance Antarctic research and the project will host a symposium of Polar researchers to discuss the cutting edge developments regarding of genomic adaptations in the polar region.<br/>Despite subzero, icy conditions that are perilous to teleost fish, the fish fauna of the isolated Southern Ocean (SO) surrounding Antarctica is remarkably bountiful. A single teleost group - the notothenioid fishes - dominate the fauna, comprising over 120 species that arose from a common ancestor. When Antarctica became isolated and SO temperatures began to plunge in early Oligocene, the prior temperate fishes became extinct. The ancestor of Antarctic notothenioids overcame forbidding polar conditions and, absent niche competition, it diversified and filled the SO. How did notothenioids adapt to freezing environmental selection pressures and achieve such extraordinary success? And having specialized to life in chronic cold for 30 myr, can they evolve in pace with today's warming climate to stay viable? Past studies of Antarctic notothenioid evolutionary adaptation have discovered various remarkable traits including the key, life-saving antifreeze proteins. But life specialized to cold also led to paradoxical trait changes such as the loss of the otherwise universal heat shock response, and of the O2-transporting hemoglobin and red blood cells in the icefish family. A few species interestingly regained abilities to live in temperate waters following the escape of their ancestor out of the freezing SO. <br/>This proposed project is the first major effort to advance the field from single trait studies to understanding the full spectrum of genomic and genetic responses to climatic and environmental change during notothenioid evolution, and to evaluate their adaptability to continuing climate change. To this end, the project will sequence the genomes of four key species that embody genomic responses to different thermal selection regimes during notothenioids' evolutionary history, and by comparative analyses of genomic structure, architecture and content, deduce the responding changes. Specifically, the project will (i) obtain whole genome assemblies of the red-blooded T. borchgrevinki and the S. American icefish C. esox; (ii) using the finished genomes from (i) as template, obtain assemblies of the New Zealand notothenioid N. angustata, and the white-blooded icefish C. gunnari, representing a long (11 myr) and recent (1 myr) secondarily temperate evolutionary history respectively. Genes that are under selection in the temperate environment but not in the Antarctic environment can be inferred to be directly necessary for that environment and the reverse is also true for genes under selection in the Antarctic but not in the temperate environment. Further, genes important for survival in temperate waters will show parallel selection between N. angustata and C. esox despite the fact that the two fish left the Antarctic at far separated time points. Finally, gene families that expanded due to strong selection within the cold Antarctic should show a degradation of duplicates in the temperate environment. The project will test these hypotheses using a number of techniques to compare the content and form of genes, the structure of the chromosomes containing those genes, and through the identification of key characters, such as selfish genetic elements, introns, and structural variants.
Arrigo, Kevin; Thomas, Leif N; Baumberger, Tamara; Resing, Joseph
No dataset link provided
Part 1.
Phytoplankton blooms throughout the world support critical marine ecosystems and help remove harmful CO2 from the atmosphere. Traditionally, it has been assumed that phytoplankton blooms in the Southern Ocean are stimulated by iron from either the continental margin or sea-ice. However, recent work demonstrates that hydrothermal vents may be an additional iron source for phytoplankton blooms. This enhancement of phytoplankton productivity by different iron sources supports rich marine ecosystems and leads to the sequestration of C in the deep ocean. Our proposed work will uncover the importance of hydrothermal activity in stimulating a large phytoplankton blooms along the southern boundary of the Antarctic Circumpolar Current just north of the Ross Sea. It will also lead towards a better understanding of the overall impact of hydrothermal activity on the C cycle in the Southern Ocean, which appears to trigger local hotspots of enhanced biological activity which are a potential as a sink for atmospheric CO2. This project will encourage the participation of underrepresented groups in ocean sciences, as well as providing educational opportunities for high school and undergraduate students, through three different programs. Stanford University’s Summer Undergraduate Research in Geoscience and Engineering (SURGE) program provides undergraduates from different US universities and diverse cultural backgrounds the opportunity to spend a summer doing a research project at Stanford. The Stanford Earth Summer Undergraduate Research Program (SESUR) is for Stanford undergraduates who want to learn more about environmental science by performing original research. Finally, Stanford’s School of Earth, Energy, and Environmental Sciences High School Internship Program enables young scientists to serve as mentors, prepares high school students for college, and serves to strengthen the partnership between Stanford and local schools. Students present their results at the Fall AGU meeting as part of the AGU Bright STaRS program. This project will form the basis of at least two Ph.D. dissertations. The Stanford student will participate in Stanford’s Woods Institute Rising Environmental Leaders Program (RELP), a year-round program that helps graduate students hone their leadership and communication skills to maximize the impact of their research. The graduate student will also participate in Stanford’s Grant Writing Academy where they will receive training in developing and articulating research strategies to tackle important scientific questions.
Part 2.
This interdisciplinary program combines satellite and ship-based measurements of a large poorly understood phytoplankton bloom (the AAR bloom) in the northwestern Ross Sea sector of the Southern Ocean with a detailed modeling study of the physical processes linking deep dissolved iron (DFe) reservoirs to the surface phytoplankton bloom. Prior to the cruise, we will implement a numerical model (CROCO) for our study region so that we can better understand the circulation, plumes, turbulence, fronts, and eddy field around the AAR bloom and how they transport and mix hydrothermally produced DFe vertically. Post cruise, observations of the vertical distribution of 3He (combined with DMn and DFe), will be used as initial conditions for a passive tracer in the model, and tracer dispersal will be assessed to better quantify the role of the various turbulent processes in upwelling DFe-rich waters to the upper ocean. The satellite-based component of the program will characterize the broader sampling region before, during, and after our cruise. During the cruise, our automated software system at Stanford University will download and process images of sea ice concentration, Chl a concentration, sea surface temperature (SST), and SSH and send them electronically to the ship. Operationally, our goal is to use all available satellite data and preliminary model results to target shipboard sampling both geographically and temporally to optimize sampling of the AAR bloom. We will use available BGC-Argo float data to help characterize the AAR bloom. In collaboration with SOCCOM, we will deploy additional BGC-Argo floats (if available) during our transit through the study area to allow us to better characterize the bloom. The centerpiece of our program will be a 40-day process study cruise in austral summer. The cruise will consist of an initial “radiator” pattern of hydrographic surveys/sections along the AAR followed by CTDs to selected submarine volcanoes. When/if eddies are identified, they will be sampled either during or after the initial surveys. The radiator pattern, or parts thereof, will be repeated 2-3 times. Hydrographic survey stations will include vertical profiles of temperature, salinity, oxygen, oxidation-reduction potential, light scatter, and PAR (400-700 nm). Samples will be collected for trace metals, ligands, 3He, and total suspended matter. Where intense hydrothermal activity is identified, samples for pH and total CO2 will also be collected to characterize the hydrothermal system. Water samples will be collected for characterization of macronutrients, and phytoplankton physiology, abundance, species composition, and size. During transits, we will continuously measure atmospheric conditions, current speed and direction, and surface SST, salinity, pCO2, and fluorescence from the ship’s systems to provide detailed maps of these parameters. The ship will be used as a platform for conducting phytoplankton DFe bioassay experiments at key stations throughout the study region both inside and outside the bloom. We will also perform detailed comparisons of algal taxonomic composition, physiology, and size structure inside and outside the bloom to determine the potential importance of each community on local biogeochemistry.
Estimating Antarctic ice sheet growth or loss is important to predicting future sea level rise. Such estimates rely on field measurements or remotely sensed based observations of the ice sheet surface, ice margins, and or ice shelves. This work examines the introduction of freshwater into the ocean to surrounding Antarctica to track meltwater from continental ice. Polar ice is depleted in two stable isotopes, 18O and D, deuterium, relative to Southern Ocean seawater and precipitation. Measurements of seawater isotopic composition in conjunction with precise observations of seawater temperature and salinity, will permit discrimination of freshwater derived from melting glacial ice from that derived from regional precipitation or sea ice melt.<br/><br/>This research describes an accepted method for determining rates and locations of meltwater entering the oceans from polar ice sheets. As isotopic and salinity perturbations are cumulative in many Antarctic coastal seas, the method allows for the detection of any marked acceleration in meltwater introduction in specific regions, using samples collected and analyzed over a period of years to decades. Impact of the project derives from use of an independent method capable of constraining knowledge about current ice sheet melt rates, their stability and potential impact on sea level rise. The project allows for sample collection taken from foreign vessels of opportunity sailing in Antarctic waters, and subsequent sharing and interpretation of data. Research partners include the U.S., Korea, China, New Zealand, the United Kingdom, and Germany. Participating collaborators will collect seawater samples for isotopic and salinity analysis at Stanford University. USAP cruises will concentrate on sampling the Ross Sea, and the West Antarctic. The work plan includes interpretation of isotopic data using box model and mixing curve analyses as well as using isotope enabled ROMS (Regional Ocean Modeling System) models. The broader impacts of the research will include development of an educational module that illustrates the scientific method and how ocean observations help society understand how Earth is changing.
The overarching goal of this research is to use cumaceans as a model system to explore invertebrate adaptations to the changing Antarctic. This project will leverage integrative taxonomy, functional, comparative and evolutionary genomics, and phylogenetic comparative methods to understand the true diversity of Cumacea in the Antarctic, identify genes and gene families experiencing expansions, selection, or significant differential expression, generate a broadly sampled and robust phylogenetic framework for Cumacea based on transcriptomes and genomes, and explore rates and timing of diversification in Antarctic cumaceans. The project will contribute to understanding of gene gain/loss, positive selection, and differential gene expression as a function of adaptation of organisms to Antarctic habitats. Phylogenomic analyses will provide a robust phylogenetic framework for Southern Ocean Cumacea. Currently, the only -omics level data that exists for the Cumacea is one transcriptome. This project will generate 8 genomes from 8 species, about 250 transcriptomes from about 70 species, and approximately 470 COI and 16S barcodes from about 100 species. Beyond the immediate scope of the current project, the genomic resources will be leveraged by members of the polar biology and invertebrate zoology communities for diverse other uses ranging from PCR primer development to inference of ancestral population sizes. In addition, curated morphological reference collections will be deposited at the Smithsonian, Los Angeles County Natural History Museum, and in the New Zealand National Water and Atmospheric Research collection at Greta Point, to assist future researchers in identification of Antarctic cumaceans.
Brittle ice has been a long-standing and consistent challenge for ice-coring projects, complicating sampling, and introducing the possibility of contamination. Several procedures have been tested to reduce brittle damage to recovered cores, but many come with high monetary and time costs. Our background research suggests that bubble size and c-axis fabric are primary drivers for brittleness and are predictable from site characteristics, enabling prediction of brittleness before coring. We propose to improve understanding of the mechanisms involved in brittle ice onset and behavior, through targeted investigations of various ice physical properties, in carefully selected samples across multiple ice-core sites, in order to guide the upcoming Hercules Dome ice-core drilling and science communities. This project will involve collaboration between Northern Arizona University, the National Science Foundation Ice Core Facility, and Pennsylvania State University, and will utilize new and existing ice-core physical properties data from several previously drilled sites. This is a high-risk, low-cost project that could yield important results, and thus is well-suited for EAGER funding. This proposal utilizes existing ice cores and does not require Antarctic fieldwork.
Non-technical description: <br/>This 4-year project is evaluating evidence of extinction patterns and depositional conditions from a high southern latitude Cretaceous-Paleogene (K-Pg) outcrop section found on Seymore Island, in the Western Antarctic Peninsula. The team is using sediment samples collected below the weathering horizon to evaluate detailed sedimentary structures, geochemistry, and microfossils in targeted stratigraphic intervals. The study will help determine if the K-Pg mass extinction was a single or double phased event and whether Seymour Island region in the geological past was a restricted, suboxic marine environment or an open well-mixed shelf. The award includes an integrated plan for student training at all levels, enhanced by a highlighted partnership with a high school earth sciences teacher working in a school serving underrepresented students.<br/>Technical description:<br/> The proposed research is applying multiple techniques to address an overarching research question for which recent studies are in disagreement: Is the fossil evidence from a unique outcropping on Seymour Island, Antarctica consistent with a single or double phased extinction? In a two-phased model, the first extinction would affect primarily benthic organisms and would have occurred ~150 kiloyears prior to a separate extinction at the K-Pg boundary. However, this early extinction could plausibly be explained by an unrecognized facies control that is obscured by surficial weathering. This team is using microfossil evidence with detailed sedimentary petrology and geochemistry data to evaluate if the fossil evidence from Seymour Island is consistent with a single or double phased extinction process. The team is using detailed sedimentary petrology and geochemistry methods to test for facies changes across the K-PG interval that would explain the apparent early extinction. Samples of core sedimentary foraminifera, siliceous microfossils, and calcareous nannofossils are being evaluated to provide a high-resolution stratigraphic resolution and to evaluate whether evidence for an early extinction is present. Additionally, the team is using multiple geochemical methods to evaluate whether there is evidence for intermittent anoxia or euxinia and/or physical restriction of the Seymore region basin. Data from this analysis will indicate if this region was a restricted, suboxic marine environment or an open well-mixed shelf.
Near the Antarctic coast, polynyas are open-water regions where extreme heat loss in winter causes seawater to become cold, salty, and dense enough to sink into the deep sea. The formation of this dense water has regional and global importance because it influences the ocean current system. Polynya processes are also tied to the amount of sea ice formed, ocean heat lost to atmosphere, and atmospheric CO2 absorbed by the Southern Ocean. Unfortunately, the ocean-atmosphere interactions that influence the deep ocean water properties are difficult to observe directly during the Antarctic winter. This project will combine field measurements and laboratory experiments to investigate whether differences in the concentration of noble gasses (helium, neon, argon, xenon, and krypton) dissolved in ocean waters can be linked to environmental conditions at the time of their formation. If so, noble gas concentrations could provide insight into the mechanisms controlling shelf and bottom-water properties, and be used to reconstruct past climate conditions. Project results will contribute to the Southern Ocean Observing System (SOOS) theme of The Future and Consequences of Carbon Uptake in the Southern Ocean. The project will also train undergraduate and graduate students in environmental monitoring, and earth and ocean sciences methods. <br/><br/>Understanding the causal links between Antarctic coastal processes and changes in the deep ocean system requires study of winter polynya processes. The winter period of intense ocean heat loss and sea ice production impacts two important Antarctic water masses: High-Salinity Shelf Water (HSSW), and Antarctic Bottom Water (AABW), which then influence the strength of the ocean solubility pump and meridional overturning circulation. To better characterize how sea ice cover, ocean-atmosphere exchange, brine rejection, and glacial melt influence the physical properties of AABW and HSSW, this project will analyze samples and data collected from two Ross Sea polynyas during the 2017 PIPERS winter cruise. Gas concentrations will be measured in seawater samples collected by a CTD rosette, from an underwater mass-spectrometer, and from a benchtop Membrane Inlet Mass Spectrometer. Noble gas concentrations will reveal the ocean-atmosphere (dis)equilibrium that exists at the time that surface water is transformed into HSSW and AABW, and provide a fingerprint of past conditions. In addition, nitrogen (N2), oxygen (O2), argon, and CO2 concentration will be used to determine the net metabolic balance, and to evaluate the efficacy of N2 as an alternative to O2 as glacial meltwater tracer. Laboratory experiments will determine the gas partitioning ratios during sea ice formation. Findings will be synthesized with PIPERS and related projects, and so provide an integrated view of the role of the wintertime Antarctic coastal system on deep water composition.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Kienle, Sarah; Trumble, Stephen J; Bonin, Carolina
No dataset link provided
The leopard seal (Hydrurga leptonyx) is an enigmatic apex predator in the rapidly changing Southern Ocean. As top predators, leopard seals play a disproportionately large role in ecosystem functioning; they also act as sentinel species that can track abiotic and biotic habitat changes. How leopard seals respond to a warming environment depends on their adaptive capacity—a species’ ability to cope with environmental change. However, leopard seals are one of the least studied apex predators on earth, hindering our ability to predict how the species is responding to polar environmental changes. Therefore, our objective is to determine leopard seals’ adaptive capacity by quantifying their ability to move (dispersal ability), adapt (genetic diversity), and change (plasticity). In Aim 1, we will determine leopard seals’ dispersal ability by assessing their distribution and movement patterns. In Aim 2, we will quantify genetic diversity by analyzing genetic variability and population structure. In Aim 3, we will examine plasticity by evaluating changes in their ecological niche and physiological responses. We have assembled an international, multidisciplinary Antarctic-experienced team to analyze existing data (e.g., photographs, census data, life history data, tissue samples, body morphometrics) collected from leopard seals across the Southern Ocean (e.g., South Shetland Islands, east and west Antarctica) over the last decade. Land- and cruise ship-based field efforts will generate comparable data from unsampled regions (e.g., Antarctic Peninsula, Chile, New Zealand,). By analyzing these historical and contemporary datasets, we will evaluate the adaptive capacity of leopard seals against the rapidly warming Southern Ocean.
Within any wild animal population there is substantial heterogeneity in reproductive rates and animal fitness. Not all individuals contribute to the population equally; some are able to produce more offspring than others and thus are considered to be of higher quality. This study aims to distinguish which physiological mechanisms (energy dynamics, aerobic capacity, and fertility) and underlying genetic factors make some Weddell seal females particularly successful at producing pups year after year, while others produce far fewer pups than the population average. In this project, an Organismal Energetics approach will identify key differences between high- and low-quality females in how they balance current and future reproductive success by tracking lactation costs, midsummer foraging success and pregnancy rates, and overwinter foraging patterns and live births the next year. Repeated sampling of individuals' physiological status (body composition, endocrinology, ovulation and pregnancy timing), will be paired with a whole-genome sequencing study. The second component of this study uses a Genome to Phenome approach to better understand how genetic differences between high- and low-quality females directly correspond to functional differences in transcription, translation, and ultimately phenotype. This component will contribute to the functional analysis and annotation of the Weddell seal genome. In combination, this project will make strides towards distinguishing the roles that plastic (physiological, behavioral) and fixed (genetic) factors play in complex, multifaceted traits such as fitness in a long-lived wild mammal. The project partners with established programs to implement extensive educational and outreach activities that will ensure wide dissemination to educators, students, and the public. It will contribute to a marine mammal exhibit at the Pink Palace Museum, and a PolarTREC science educator will participate in field work in Antarctica.
The goal of this study is to identify and distinguish different source areas of glacial sediment in the McMurdo Dry Valleys, Antarctica to determine past glacial flow direction. Understanding ice flow is critical for determining how the Antarctic Ice Sheets have behaved in the past. Such insight is fundamental for allowing scientists to predict how the Antarctic Ice Sheets will evolve and, in turn, forecast how much and how fast sea level may rise. The project study site, the McMurdo Dry Valleys, contain a tremendous record of glacial deposits on land that extends back at least 14 million years. Chemistry of the rocks within the glacial deposits hold clues to the sources of ice that deposited the material. The chemical analyses of the glacial deposits will allow mapping of the former extent of glaciations providing a better understand of ice flow history. The mapping of the largest ice sheet expansion of the past 14 million years in the McMurdo Dry Valleys is of broad interest to the global climate change community. Undergraduate students comprise the majority of the field teams and will be responsible for sample preparation and analysis in the laboratory. <br/><br/>This project utilizes new geochemical techniques to test hypotheses about the source, extent, and flow patterns of the glacier ice that deposited glacial tills in the McMurdo Dry Valleys, Antarctica (MDV). The MDV contain an unparalleled terrestrial archive of glacial deposits, which record multiple sources of ice that deposited them. These include the northeast flowing ice that overrode the Transantarctic Mountains, the eastward expansion of the East Antarctic Ice Sheet, the westward extension of the Ross Ice Shelf representing an expansion of the West Antarctic Ice Sheet, and the growth of local alpine glaciers. The glacial tills and drifts in the Antarctic are typically isolated in patches or disjointed outcrop patterns making it difficult to correlate tills and determine their source. This project will undertake a systematic study of the tills in the McMurdo Dry Valleys to determine their provenance with a variety of geochemical techniques including major and minor element analyses with X-ray fluorescence, heavy mineral composition, soil salt concentration, and determining the uranium-lead (U-Pb) ages of zircon sands contained in these tills. The primary tool will be the age distribution of the population of detrital zircon in a glacial drift because it reflects the source of the tills and provides a unique geochemical "fingerprint" used to distinguish source areas while correlating units across different sites. A deliverable from this project will be a community available library of zircon fingerprints for mapped glacial tills from archived samples at the Polar Rock Repository and the systematic collection of samples in the MDV.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Walker, Catherine; Zhang, Weifeng; Seroussi, Helene
No dataset link provided
The majority of mass loss from the Antarctic Ice Sheet, a major contributor to sea level rise, occurs at its margins, where ice meets the ocean. Glaciers and ice streams flow towards the coast and can go afloat over the water, forming ice shelves. Ice shelves make up almost half of the entire Antarctic coastline, and hold back the flow of inland ice in Antarctica continent; thus they are integral to the overall stability of the Antarctic Ice Sheet. Ice shelves lose mass by two main processes: iceberg calving and basal melting. Temporal and spatial fluctuations in both are driven by various processes; a major driver of ice shelf melt is the heat provided by the neighboring Southern Ocean. Ocean heat, in turn, is driven by various aspects of the ice shelf environment. One of the most significant contributors to changes in the ocean’s heat content is the presence of sea ice. This research will focus on the effects of coastal polynyas (areas of open water amidst sea ice), how they modulate the local ocean environment, and how that environment drives ice shelf basal melting. To date, the relationship between polynyas and ice shelf melt has not been characterized on an Antarctic-wide scale. Understanding the feedbacks between polynya size and duration, ocean stratification, and ice shelf melt, and the strength of those feedbacks, will improve the ability to characterize influences on the long-term stability of ice shelves, and in turn, the Antarctic Ice Sheet as a whole. A critical aspect of this study is that it will provide a framework for understanding ice shelf-ocean interaction across a diverse range of geographic settings. This, together with improvements of various models, will help interpret the impacts of future climate change on these systems, as their responses are likely quite variable and, on the whole, different from the large-scale response of the ice sheet. This project will also provide a broader context to better design future observational studies of specific coastal polynya and ice shelf processes.
Interpreting highly compressed portions of ice cores is increasingly important as projects target climate records in basal ice, and in ice recovered from blue-ice areas. This project will integrate precisely co-registered electrical conductivity measurements (ECM), hyperspectral imaging, laser ablation ICPMS measurements of impurities, and ice physical properties to investigate sub-cm chemical and physical variations in polar ice. This work will establish to what extent annual layer interpretations of polar ice with sub-cm layering is possible. Critical to resolving thin ice layers is understanding the across-core variations which may obscure or distort the vertical layering. Analyses will be focused on samples from WAIS Divide, SPICEcore, and GISP2, which have well established seasonal cycles that yielded benchmark timescales, as well a large diameter ice core from a blue ice area.
The Amundsen Sea, near the fastest melting Antarctic glaciers, hosts one of the most productive polar ecosystems in the world. Phytoplankton serve as the base of the food chain, and their growth also removes carbon dioxide from the atmosphere. Phytoplankton growth is fertilized in this area by nutrient iron (Fe), which is only present at low concentrations in seawater. Prior studies have shown the seabed sediments may provide Fe to the Amundsen Sea ecosystem. However, sediment sources of Fe have never been studied here directly. This project fills this gap by analyzing sediments from the Amundsen Sea and investigating whether sediment Fe fertilizes plankton growth. The results will help scientists understand the basic ecosystem drivers and predict the effects of climate change on this vibrant, vulnerable region. This project also emphasizes inclusivity and openness to the public. The researchers will establish a mentoring network for diverse polar scientists through the Polar Impact Network and communicate their results to the public through CryoConnect.org.
This project leverages samples already collected from the Amundsen Sea (NBP22-02) to investigate sediment Fe cycling and fluxes. The broad questions driving this research are 1) does benthic Fe fertilize Antarctic coastal primary productivity, and 2) what are the feedbacks between benthic Fe release and carbon cycling in the coastal Antarctic? To answer these questions, the researchers will analyze pore water Fe content and speciation and calculate fluxes of Fe across the sediment-water interface. These results will be compared to sediment characteristics (e.g., organic carbon content, reactive Fe content, proximity to glacial sources) to identify controls on benthic Fe release. This research dovetails with and expands on the science goals of the “Accelerating Thwaites Ecosystem Impacts for the Southern Ocean” (ARTEMIS) project through which the field samples were collected. In turn, the findings of ARTEMIS regarding modeled and observed trace metal dynamics, surface water productivity, and carbon cycling will inform the conclusions of this project, allowing insight into the impact of benthic Fe in the whole system. This project represents a unique opportunity for combined study of the water column and sediment biogeochemistry which will be of great value to the marine biogeochemistry community and will inform future sediment-ocean studies in polar oceanography and beyond.
Reliable predictions are needed for how populations of wild species, especially those at high latitudes, will respond to future environmental conditions. This study will use a strategic extension of the long-term demographic research program that has been conducted annually on the Erebus Bay population of Weddell seals since 1978 to help meet that need. Recent analyses of the study population indicate strong annual variation in reproduction, abundance, and population composition. The number of new immigrant mothers that join the population each year has recently grown such that most new mothers are now immigrants. Despite the growing number of immigrants, the demographic importance and geographic origins of immigrants are unknown. The research will (1) add new information on drivers of annual variation in immigrant numbers, (2) compare and combine information on the vital rates and demographic role of immigrant females and their offspring with that of locally born females, and (3) add genomic analyses that will quantify levels of genetic variation in and gene flow among the study population and other populations in the Ross Sea. The project will continue the long-term monitoring of the population at Erebus Bay and characterize population dynamics and the role of immigration using a combination of mark-recapture analyses, stochastic population modeling, and genomic analyses. The study will continue to (1) provide detailed data on individual seals to other science teams, (2) educate and mentor individuals in the next generation of ecologists, (3) introduce two early-career, female scientists to Antarctic research, and (4) add genomics approaches to the long-term population study of Erebus Bay Weddell seals. The Informal Science Education program will expand on the project’s recent and successful efforts by producing and delivering short-form videos through an interactive web portal and diverse social-media technologies. The Informal Science Education program will continue to update and add new topics to a multimedia-enhanced electronic book about the project’s research on Weddell seals that will be freely available to the public. The outreach efforts will increase the length of the book from ~140 to ~225 pages and add new topics such as learning about seals using genomics and how seals respond to a changing world.
Traditional models of oceanic food chains have consisted of photosynthetic algae (phytoplankton) being ingested by small animals (zooplankton), which were ingested by larger animals (fish). These traditional models changed as new methods allowed recognition of the importance of bacteria and other non-photosynthetic protozoa in more complex food webs. More recently, the wide-spread existence of mixotrophs (organisms that can both photosynthesize and ingest food particles) and their importance as microbial predators has been recognized in many oceanographic areas. In the Southern Ocean, the only two surveys of mixotrophs have suggested that there may be seasonal differences in their importance as predators. During the long polar night (winter), the ability of mixotrophs to ingest particulate food may aid in their survival thus ensuring a sufficient population in spring to support a phytoplankton bloom once photosynthesis rates can increase. Thus mixotrophs may provide a critical early food source upon which zooplankton and larger animals depend on for growth and reproduction. This project will advance understanding of mixotroph diversity and their ecological impact within the Southern Ocean microbial food web. Specifically, efforts will be focused on mixotrophy in the western Antarctica peninsula region during the austral spring and autumn when there are likely to be changes in the relative importance of photosynthesis and ingestion to mixotrophs. The project will provide research opportunities for undergraduate and graduate students and a post-doctoral researcher. There will be real-time outreach from the Southern Ocean to the public via blogs and interviews, and to high school art students through an established program that blends science and art education. Despite traditional views of protists as either "phototrophic" or "heterotrophic," there are many photosynthetic protists that consume prey (mixotrophy). Mixotrophy is a widespread phenomenon in aquatic systems and phytoplankton groups with known mixotrophic species, notably chrysophytes, cryptophytes, prymnesiophytes, prasinophytes and dinoflagellates, are present and often abundant in Antarctic waters. However, in the Southern Ocean, the presence of mixotrophic phytoflagellates has been surveyed only twice prior to this project: in the Ross Sea during Austral spring 2008 and summer 2011. The primary goals of the project are to gain better understanding of mixotroph diversity and their ecological impact with respect to the Southern Ocean microbial food web. The contribution of mixotrophs to primary production and bacterial consumption is likely linked to the taxonomic composition of the community and the abundance of particular species. Abundances of novel mixotrophic species will be evaluated via qPCR, which will be coupled with assessments of rates of feeding and photosynthesis with the goal of describing how active mixotrophs direct the movement of carbon through food webs. These experiments will help the determination of how viable and widespread mixotrophy is as a nutritional strategy in polar waters and give direct information on the currently unknown diversity of mixotrophic taxa under different environmental conditions occurring in austral spring and autumn. Furthermore, the methods will simultaneously yield information on the whole communities of protists - mixotrophic, phototrophic and heterotrophic. In addition, a method to examine aspects of the taxonomic and functional diversities of the bacterivorous/mixotrophic community will be employed. A thymidine analog (BrdU) will be used to label DNA of eukaryotes feeding on bacteria. The BrdU-labeled eukaryotic DNA will be isolated using immunoprecipitation. High-throughput sequencing of the labeled DNA (bacterivores) versus unlabeled community DNA will determine the diversity of bacterivorous mixotrophs relative to other microeukaryotes. Flow cytometric sorting based on chlorophyll to focus on mixotrophic species. These approaches will elucidate a gap in current knowledge of the influence of microbial interactions in the Southern Ocean under different conditions. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Pygoscelis penguins are central place foragers during the summer while they raise their chicks. They leave and return to the same colony location after hunting for food and rely on the availability of Antarctic krill, their primary food source. This research focuses on whether penguin diets and colony location reflect the retention of prey around and near colonies on the West Antarctic Peninsula. Eddies and other oceanographic processes may facilitate prey retention at certain locations, driving penguin colony establishment and success.
This project hypothesizes that Pygoscelis penguin diets will be composed of more Antarctic krill (Euphausia superba) when local prey retention is high, possibly due to subsurface eddies. This hypothesis will be tested using satellite-based estimates of Pygoscelis penguin diet composition using multispectral sensor data to estimate nitrogen values and infer trophic level. Prey retention will be calculated along the peninsula using the Regional Ocean Modeling System (ROMS). Simulated particles and diel vertical migration will be used to mimic krill behavior. These particles can be experimentally seeded across multiple depths in multiple years to assess residence times in the system. Using penguin colony data from the Mapping Application for Penguin Populations and Projected Dynamics (MAPPPD), the PI will correlate diet and retention metrics to local penguin colony growth and persistence and build a predictive model of where colonies may form in the future.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Presently, Antarctica's glaciers are melting as Earth's atmosphere and the Southern Ocean warm. Not much is known about how Antarctica's ice sheets might respond to ongoing and future warming, but such knowledge is important because Antarctica's ice sheets might raise global sea levels significantly with continued melting. Over time, mud accumulates on the sea floor around Antarctica that is composed of the skeletons and debris of microscopic marine organisms and sediment from the adjacent continent. As this mud is deposited, it creates a record of past environmental and ecological changes, including ocean depth, glacier advance and retreat, ocean temperature, ocean circulation, marine ecosystems, ocean chemistry, and continental weathering. Scientists interested in understanding how Antarctica's glaciers and ice sheets might respond to ongoing warming can use a variety of physical, biological, and chemical analyses of these mud archives to determine how long ago the mud was deposited and how the ice sheets, oceans, and marine ecosystems responded during intervals in the past when Earth's climate was warmer. In this project, researchers from the University of South Florida, University of Massachusetts, and Northern Illinois University will reconstruct the depth, ocean temperature, weathering and nutrient input, and marine ecosystems in the central Ross Sea from ~17 to 13 million years ago, when the warm Miocene Climate Optimum transitioned to a cooler interval with more extensive ice sheets. Record will be generated from new sediments recovered during the International Ocean Discovery Program (IODP) Expedition 374 and legacy sequences recovered in the 1970?s during the Deep Sea Drilling Program. Results will be integrated into ice sheet and climate models to improve the accuracy of predictions.
Algae in the surface ocean convert carbon dioxide into organic carbon through photosynthesis. The biological carbon pump transports this organic carbon from the atmosphere to the deep ocean where it can be stored for tens to hundreds of years. Annually, the amount transported is similar to that humans are currently emitting by burning fossil fuels. However, at present we cannot predict how this important process will change with a warming ocean. These investigators plan to develop a 15+ year time-series of vertical carbon transfer for the Western Antarctic Peninsula; a highly productive Antarctic ecosystem. This region is also rapid transition to warmer temperatures leading to reduced sea ice coverage. This work will help researchers better understand how the carbon cycle in the Western Antarctic Peninsula will respond to climate change. The researchers will develop the first large-scale time-series of carbon flux anywhere in the ocean. This research will also support the education and training of a graduate student and support the integration of concepts in Antarctic research into two undergraduate courses designed for non-science majors and advanced earth science students. The researchers will also develop educational modules for introducing elementary and middle-school age students to important concepts such as gross and net primary productivity, feedbacks in the marine and atmospheric systems, and the differences between correlation and causation. Results from this proposal will also be incorporated into a children?s book, ?Plankton do the Strangest Things?, that is targeted at 5-7 year olds and is designed to introduce them to the incredible diversity and fascinating adaptations of microscopic marine organisms.<br/><br/> This research seeks to leverage 6 years (2015-2020) of 234Th samples collected on Palmer LTER program, 5 years of prior measurements (2009-2010, 2012-2014), and upcoming cruises (2021-2023) to develop a time-series of summertime particle flux in the WAP that stretches for 15 years. The 238U-234Th disequilibrium approach utilizes changes in the activity of the particle-active radio-isotope 234Th relative to its parent nuclide 238U to quantify the flux of sinking carbon out of the surface ocean (over a time-scale of ~one month). This proposal will fund 234Th analyses from nine years? worth of cruises (2015-2023) and extensive analyses designed to investigate the processes driving inter-annual variability in the BCP. These include: 1) physical modeling to quantify the importance of advection and diffusion in the 234Th budget, 2) time-series analyses of particle flux, and 3) statistical modeling of the relationships between particle flux and multiple presumed drivers (biological, chemical, physical, and climate indices) measured by collaborators in the Palmer LTER program. This multi-faceted approach is critical for linking the measurements to models and for predicting responses to climate change. It will also test the hypothesis that export flux is decreasing in the northern WAP, increasing in the southern WAP, and increasing when integrated over the entire region as a result of earlier sea ice retreat and a larger ice-free zone. The project will also investigate relationships between carbon export and multiple potentially controlling factors including: primary productivity, algal biomass and taxonomic composition, biological oxygen saturation, zooplankton biomass and taxonomic composition, bacterial production, temperature, wintertime sea ice extent, date of sea ice retreat, and climate modes.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part 1: Non-technical description:
It is well known that the Southern Ocean plays an important role in global carbon cycling and also receives a disproportionately large influence of climate change. The role of marine viruses on ocean productivity is largely understudied, especially in this global region. This team proposes to use combination of genomics, flow cytometry, and network modeling to test the hypothesis that viral biogeography, infection networks, and viral impacts on microbial metabolism can explain variations in net community production (NCP) and carbon cycling in the Southern Ocean. The project includes the training of a postdoctoral scholar, graduate students and undergraduate students. It also includes the development of a new Polar Sci ReachOut program in partnership with the University of Michigan Museum of Natural History especially targeted to middle-school students and teachers and the general public. The team will also produce a Science for Tomorrow (SFT) program for use in middle schools in metro-Detroit communities and lead a summer Research Experience for Teachers (RET) fellows.
Part 2: Technical description:
The study will leverage hundreds of existing samples collected for microbes and viruses from the Antarctic Circumpolar Expedition (ACE). These samples provide the first contiguous survey of viral diversity and microbial communities around Antarctica. Viral networks are being studied in the context of biogeochemical data to model community networks and predict net community production (NCP), which will provide a way to evaluate the role of viruses in Southern Ocean carbon cycling. Using cutting edge molecular and flow cytometry approaches, this project addresses the following questions: 1) How/why are Southern Ocean viral populations distributed across environmental gradients? 2a) Do viruses interfere with "keystone" metabolic pathways and biogeochemical processes of microbial communities in the Southern Ocean? 2b) Does nutrient availability or other environmental variables drive changes in virus-microbe infection networks in the Southern Ocean? Results will be used to develop and evaluate generative models of NCP predictions that incorporate the importance of viral traits and virus-host interactions.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Freshwater discharges from melting high-latitude continental ice glacial reserves strongly control salt budgets, circulation and associated ocean water mass formation arising from polar ice shelves. These are different in nature than freshwater inputs associated with riverine coastal inputs. The PI proposes an observational deployment to measure a specific, previously-identified example of a coastal freshwater-driven current, the Antarctic Peninsula Coastal Current (APCC). <br/> <br/>The research component of this CAREER project aims to improve understanding of the dynamics of freshwater discharge around the Antarctic continent. Associated research questions pertain to the i) controls on the cross- and along-shelf spreading of fresh, buoyant coastal currents, ii) the role of distributed coastal freshwater sources (as opposed to 'point' source river outflow sources typical of lower latitudes), and iii) the contribution of these coastal currents to water mass transformation and heat transfer on the continental shelf. An educational CAREER program component leverages a series of field experiences and research outputs including data, model outputs, and theory, to bring polar science to the classroom and the general public, as well as training a new polar scientist. This combined strategy will allow the investigator to lay the foundation for a successful academic career as a researcher and teacher at the University of Delaware. The project will also provide the opportunity to train a PhD student. Informal outreach efforts will include giving public lectures at University of Deleware's sponsored events, including Coast Day, a summer event that attracts 8000-10000 people, and remote lectures from the field using an existing outreach network. This proposal requires fieldwork in the Antarctic.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Ross Sea, Antarctica, is one of the last large intact marine ecosystems left in the world, yet is facing increasing pressure from commercial fisheries and environmental change. It is the most productive stretch of the Southern Ocean, supporting an array of marine life, including Antarctic toothfish the regions top fish predator. While a commercial fishery for toothfish continues to grow in the Ross Sea, fundamental knowledge gaps remain regarding toothfish ecology and the impacts of toothfish fishing on the broader Ross Sea ecosystem. Recognizing the global value of the Ross Sea, a large (>2 million km2) marine protected area was adopted by the multi-national Commission for the Conservation of Antarctic Marine Living Resources in 2016. This research will fill a critical gap in the knowledge of Antarctic toothfish and deepen understanding of biological-physical interactions for fish ecology, while contributing to knowledge of impacts of fishing and environmental change on the Ross Sea system. This work will further provide innovative tools for studying connectivity among geographically distinct fish populations and for synthesizing and assessing the efficacy of a large-scale marine protected area. In developing an integrated research and education program in engaged scholarship, this project seeks to train the next generation of scholars to engage across the science-policy-public interface, engage with Southern Ocean stakeholders throughout the research process, and to deepen the publics appreciation of the Antarctic.
A major research priority among Ross Sea scientists is to better understand the life history of the Antarctic toothfish and test the efficacy of the Ross Sea Marine Protected Area (MPA) in protecting against the impacts of overfishing and climate change. Like growth rings of a tree, fish ear bones, called otoliths, develop annual layers of calcium carbonate that incorporates elements from their environment. Otoliths offer information on the fishs growth and the surrounding ocean conditions. Hypothesizing that much of the Antarctic toothfish life cycle is structured by ocean circulation, this research employs a multi-disciplinary approach combining age and growth work with otolith chemistry testing, while also utilizing GIS mapping. The project will measure life history parameters as well as trace elements and stable isotopes in otoliths in three distinct sets collected over the last four decades in the Ross Sea. The information will be used to quantify the transport pathways Antarctic toothfish use across their life history, and across time, in the Ross Sea. The project will assess if toothfish populations from the Ross Sea are connected more widely across the Antarctic. By comparing life history and otolith chemistry data across time, the researchers will assess change in life history parameters and spatial dynamics and seek to infer if these changes are driven by fishing or climate change. Spatially mapping of these data will allow an assessment of the efficacy of the Ross Sea MPA in protecting toothfish and where further protections might be needed.
This award reflects NSF''s statutory mission and has been deemed worthy of support through evaluation using the Foundation''s intellectual merit and broader impacts review criteria.
Cores drilled through the Antarctic ice sheet provide a remarkable window on the evolution of Earth’s climate and unique samples of the ancient atmosphere. The clear link between greenhouse gases and climate revealed by ice cores underpins much of the scientific understanding of climate change. Unfortunately, the existing data do not extend far enough back in time to reveal key features of climates warmer than today. COLDEX, the Center for Oldest Ice Exploration, will solve this problem by exploring Antarctica for sites to collect the oldest possible record of past climate recorded in the ice sheet. COLDEX will provide critical information for understanding how Earth’s near-future climate may evolve and why climate varies over geologic time. New technologies will be developed for exploration and analysis that will have a long legacy for future research. An archive of old ice will stimulate new research for the next generations of polar scientists. COLDEX programs will galvanize that next generation of polar researchers, bring new results to other scientific disciplines and the public, and help to create a more inclusive and diverse scientific community.
Knowledge of Earth’s climate history is grounded in the geologic record. This knowledge is gained by measuring chemical, biological and physical properties of geologic materials that reflect elements of climate. Ice cores retrieved from polar ice sheets play a central role in this science and provide the best evidence for a strong link between atmospheric carbon dioxide and climate on geologic timescales. The goal of COLDEX is to extend the ice-core record of past climate to at least 1.5 million years by drilling and analyzing a continuous ice core in East Antarctica, and to much older times using discontinuous ice sections at the base and margin of the ice sheet. COLDEX will develop and deploy novel radar and melt-probe tools to rapidly explore the ice, use ice-sheet models to constrain where old ice is preserved, conduct ice coring, develop new analytical systems, and produce novel paleoclimate records from locations across East Antarctica. The search for Earth’s oldest ice also provides a compelling narrative for disseminating information about past and future climate change and polar science to students, teachers, the media, policy makers and the public. COLDEX will engage and incorporate these groups through targeted professional development workshops, undergraduate research experiences, a comprehensive communication program, annual scientific meetings, scholarships, and broad collaboration nationally and internationally. COLDEX will provide a focal point for efforts to increase diversity in polar science by providing field, laboratory, mentoring and networking experiences for students and early career scientists from groups underrepresented in STEM, and by continuous engagement of the entire COLDEX community in developing a more inclusive scientific culture.
Understanding and being able to more reliably forecast ice mass loss from Antarctica is a critical research priority for Antarctic Science. Massive ice shelves buttress marine terminating glaciers, slowing the rate that land ice reaches the sea and, in turn, restraining the rate of sea level rise. To date, most work has focused on the destabilizing impacts of warmer air and water temperatures, resulting in melting that thins and weakens ice shelves. However, recent findings indicate that sea ice does not protect ice shelves from wave impacts as much as previously thought, which has raised the possibility that tsunamis and other ocean waves could affect shelf stability. This project will assess the potential for increased shelf fracturing from the impact of tsunamis and from heightened wave activity due to climate-driven changes in storm patterns and reduced sea-ice extent by developing models to investigate how wave impacts damage ice shelves. The modeling effort will allow for regional comparisons between large and small ice shelves, and provide an evaluation of the impacts of changing climate and storm patterns on ice shelves, ice sheets, glaciers, and, ultimately, sea level rise. This project will train graduate students in mathematical modeling and interdisciplinary approaches to Earth and ocean sciences.<br/><br/>This project takes a four-pronged approach to estimating the impact of vibrations on ice shelves at the grounding zone due to tsunamis, very long period, infragravity, and storm-driven waves. First, the team will use high-resolution tsunami modeling to investigate the response of ice shelves along the West Antarctic coast to waves originating in different regions of the Pacific Ocean. Second, it will compare the response to wave impacts on grounding zones of narrow and wide ice shelves. Third, it will assess the exposure risk due to storm forcing through a reanalysis of weather and wave model data; and, finally, the team will model the propagation of ocean-wave-induced vibrations in the ice from the shelf front to and across the grounding zone. In combination, this project aims to identify locations along the Antarctic coast that are subject to enhanced, bathymetrically-focused, long-period ocean-wave impacts. Linkages between wave impacts and climate arise from potential changes in sea-ice extent in front of shelves, and changes in the magnitude, frequency, and tracks of storms. Understanding the effects of ocean waves and climate on ice-shelf integrity is critical to anticipate their contribution to the amplitude and timing of sea-level rise. Wave-driven reductions in ice-shelf stability may enhance shelf fragmentation and iceberg calving, reducing ice shelf buttressing and eventually accelerating sea-level rise.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Antarctic Peninsula is experiencing rapid environmental changes, which will influence the community of organisms that live there. However, we know very little about the microscopic organisms living in the soil in this region. Soil biology (including bacteria, fungi, and invertebrates) are responsible for many important processes that sustain ecosystems, such as nutrient recycling. Without understanding the environmental conditions that influence soil biodiversity along the Antarctic Peninsula, our ability to predict the consequences of global change is strongly limited. This project will identify the soil community at many sites along the Antarctic Peninsula to discover how the community changes with environmental conditions from north to south. The project will also identify how the soil community at each site differs under different types of plants. Understanding more about the ways in which plant cover and climate conditions influence soil biodiversity will allow predictions of how communities will respond to future changes such as climate warming and invasive plant species. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. The investigators will engage with outreach to K-12 students and the general public both directly and through a blog and will participate in workshops for K-12 teachers. Additionally, the project will provide the opportunity for many undergraduate and graduate students of diverse backgrounds to be trained in interdisciplinary research.<br/><br/>The investigators will determine the nature and strength of plant-soil linkages in influencing soil community composition and diversity over a latitudinal gradient of environmental and climatic conditions. The goals are to (1) increase our understanding of current biogeography and diversity by providing in-depth knowledge of soil community composition and complexity as it relates to environmental and climatic characteristics; and (2) determine the nature of aboveground-belowground community linkages over varying spatial scales. The team will identify the composition and diversity of soil communities under key habitat types (grass, moss, algae, etc.). Microbial communities (bacteria, fungi, archaea) will be investigated using pyrosequencing for community composition analysis and metagenomic sequencing to identify functional capabilities. Invertebrates (nematodes, tardigrades, rotifers, microarthropods) will be extracted and identified to the lowest possible taxonomic level. Soil chemistry (pH, nutrient content, soil moisture, etc.) and climate conditions will be measured to determine the relationship between soil communities and physical and chemical properties. Structural equation modeling will be used to identify aboveground-belowground linkage pathways and quantify link strengths under varying environmental conditions.
Part 1: Non-technical description:
With support from the Office of Polar Programs, this project will evaluate how an important part of the food web in the coastal ocean of Antarctica will respond to climate change. The focal study organism in the plankton is a shelled mollusk, the Antarctic pteropod, Limacina helicina antarctica, a Southern Ocean organism that this known to respond to climate driven changes in ocean acidification and ocean warming. Ocean acidification, the lowering of ocean pH via the absorption of atmospheric carbon dioxide in the surface of the ocean, is a change in the ocean that is expected to cross deleterious thresholds of pH within decades. This study will improve understanding of how pteropods will respond, which will provide insight into predicting the resilience of the Antarctic marine ecosystem during future changes, one of the planets last marine wildernesses. The project will use tools of molecular biology to examine specifically how gene expression is modulated in the pteropods, and further, how the changes and regulation of genes act to resist the stress of low pH and high temperature. In addition, this project supports the training of Ph.D. graduate students and advances the goal of inclusive excellence in STEM and in marine sciences, in particular. The students involved in this project are from groups traditionally under-represented in marine science including first-generation college students. Overall, the project contributes to the development of the U.S. work force and contributes to diversity and inclusive excellence in the geosciences.
Part 2: Technical description:
The overarching goal of this project is to investigate the molecular response of the Antarctic thecosome pteropod, Limacina helicina antarctica to ocean acidification (OA) and ocean warming. The project will investigate changes in the epigenome of juvenile L. h. antarctica, by assessing the dynamics of DNA methylation in response to three scenarios of environmental conditions that were simulated in laboratory mesocosm CO2 experiments: (1) present-day pCO2 conditions for summer and winter, (2) future ocean acidification expected within 10-15 years, and (3) a multiple stressor experiment to investigate synergistic interaction of OA and high temperature stress. Recent lab-based mesocosm experiment research showed significant changes in the dynamics of global DNA methylation in the pteropod genome, along with variation in gene expression in response to abiotic changes. Thus, it is clear that juvenile L. h. antarctica are capable of mounting a substantial epigenetic response to ocean acidification. However, it is not known how DNA methylation, as an epigenetic process, is modulating changes in the transcriptome. In order to address this gap in the epigenetic knowledge regarding pteropods, the project will use next-generation sequencing approaches (e.g., RNA sequencing and reduced representation bisulfite sequencing) to integrate changes in methylation status with changes in gene expression in juvenile pteropods. Overall, this investigation is an important step in exploring environmental transcriptomics and phenotypic plasticity of an ecologically important member of Southern Ocean macrozoooplankton in response to anthropogenic climate change.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part I: Non-technical summary<br/>The Antarctic Peninsula warmed very rapidly in the late part of the 20th century, much faster than the global average, and this warming is predicted to resume and continue over the rest of the 21st century. One consequence of this rapid warming is the melting and subsequent retreat of glaciers, leading to an increase in newly-exposed land on the Peninsula that was previously covered with ice. Once new terrain is exposed, the process of ecological succession begins, with the arrival of early-colonizing plants, such as moss and lichens, and soil organisms - a process commonly referred to as the “greening” of Antarctica. Early stages of succession will be an increasingly common feature on the Antarctic Peninsula, but the mechanisms by which they occur on the Antarctic continent is not well understood. Once the plants have established on the newly-exposed soil, they can change many important properties, such as water dynamics, nutrient recycling, soil development, and habitat for microscopic organisms, which will ultimately determine the structure and functioning of the future ecosystem as it develops. These relationships between vegetation, soil, and the associated microorganisms, referred to as “plant-soil” interactions, are something we know virtually nothing about. This project will be the first to make a comprehensive study of how the type of colonizing plant, and the expansion of those plants from climate change, will influence terrestrial ecosystems in Antarctica. Understanding these processes is critical to understanding how the greening Antarctica is occurring and how soil communities and processes are influenced by these expanding plant communities. Through this work the research team, will also be intensively training undergraduate and graduate students, including training of students from underrepresented groups and collaborative training of students from Chile and the US. Additionally, the research groups will continue their focus on scientific outreach with K-12 schools and the general public to expand awareness of the effects of climate change in Antarctica.<br/><br/>Part II: Technical summary<br/>In this study, the researchers will use surveys across succession sites along the Antarctic Peninsula and Scotia Arc as well as a manipulative field experiment at glacier succession sites to test how species-specific plant functional traits impact soil properties and associated microbial and invertebrate communities in a greening Antarctica. In doing so, they will pursue three integrated aims to understand how Antarctic plant functional traits alter their soil environment and soil communities during succession after glacial retreat. AIM 1) Characterize six fundamental plant functional traits (thermal conductivity, water holding capacity, albedo, decomposability, tissue nutrient content, and secondary chemistry) among diverse Antarctica flora; AIM 2) Measure the relative effects of fundamental plant functional traits on soil physical properties and soil biogeochemistry across glacial succession gradients in Antarctica; and AIM 3) Measure the relative effects of fundamental plant functional traits on soil microbial and invertebrate communities across glacial succession gradients in Antarctica. They will explore how early-colonizing plants, especially mosses and lichens, alter soil physical, biogeochemical, and biological components, potentially impacting later patterns of succession. The researhcers will use intensive surveys of plant-soil interactions across succession sites and a manipulative transplant experiment in the South Shetland Islands, Antarctica to address their aims. The investigators will collect data on plant functional traits and their effects on soil physical properties, biogeochemistry, biotic abundance, and microbial metagenomics. The data collected will be the first comprehensive measures of the relative importance of plant functional types during glacial retreat and vegetative expansion from climate change in Antarctica, aiding our understanding of how plant functional group diversity and abundance are changing in a greening Antarctica.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Weddell Gyre is one of the major components of the Southern Ocean circulation system, linking heat and carbon fluxes in the Antarctic Circumpolar Current to the continental margins. Water masses entering the Weddell Gyre are modified as they move in a great circular route around the gyre margin and change through processes involving air-sea-cryosphere interactions as well as through ocean eddies that mix properties across the gyre boundaries. Some of the denser water masses exit the gyre through pathways along the northern boundary, and ultimately ventilate the global deep ocean as Antarctic Bottom Water. While in-situ and satellite observations, as well as computer modeling efforts, provide estimates of the large-scale average flow within the gyre, details of the smaller-scale, or "mesoscale" eddy flow remain elusive. The proposed research will quantify mixing due to mesoscale eddies within the Weddell Gyre, as well as the transport of incoming deep water from the northeast, thought to be a result of transient eddies. Since the Weddell Gyre produces source water for about 40% of Antarctic Bottom Water formation, understanding the dynamics in this region helps to identify causes of documented changes in global bottom waters. This in turn, will give insight into how climate change is affecting global oceans, through modification of dense polar waters and Antarctic Bottom Water characteristics.
This project aims to track 153 RAFOS-enabled Argo floats in the ice-covered regions of the Weddell Gyre. The resultant tracks along with all available Argo and earlier float data will be used to calculate Eulerian and Lagrangian means and eddy statistics for the Weddell Gyre. The study will link RAFOS tracks with Argo profiles under ice, allowing one to characterize the importance of eddies in water column modification at critical ice-edge boundaries and leads. With RAFOS tracks near the northeastern limit of the gyre, the project will investigate the eddy-driven processes of incoming Circumpolar Deep Water, to understand better the mechanisms and volume fluxes involved. Previous work shows that a large fraction of the mean circulation in the southern and western limits of the gyre, where it contacts the Antarctic continent, occurs in a narrow boundary layer above the slope. The research here will integrate this flow structure into a complete interior and boundary layer mean circulation synthesis. The findings and products from the proposed work will improve the positioning of Argo profiles in the polar regions, which would allow for more accurate climatological maps and derived quantities. Estimates of meso-scale mixing may serve as a foundation for the development of new parameterization schemes employed in climate models, as well as local and global ocean circulation models in polar regions.
This award supports a project to investigate the sensitivity of the Antarctic ice sheet (AIS) to global climate change over the last two Glacial/Interglacial cycles. The intellectual merit of the project is that despite its importance to Earth's climate system, we currently lack a full understanding of AIS sensitivity to global climate change. This project will reconstruct and precisely date the history of marine-based ice in the Ross Sea sector over the last two glacial/interglacial cycles, which will enable a better understanding of the potential driving mechanisms (i.e., sea-level rise, ice dynamics, ocean temperature variations) for ice fluctuations. This will also help to place present ice?]sheet behavior in a long-term context. During the last glacial maximum (LGM), the AIS is known to have filled the Ross Embayment and although much has been done both in the marine and terrestrial settings to constrain its extent, the chronology of the ice sheet, particularly the timing and duration of the maximum and the pattern of initial recession, remains uncertain. In addition, virtually nothing is known of the penultimate glaciation, other than it is presumed to have been generally similar to the LGM. These shortcomings greatly limit our ability to understand AIS evolution and the driving mechanisms behind ice sheet fluctuations. This project will develop a detailed record of ice extent and chronology in the western Ross Embayment for not only the LGM, but also for the penultimate glaciation (Stage 6), from well-dated glacial geologic data in the Royal Society Range. Chronology will come primarily from high-precision Accelerator Mass Spectrometry (AMS) Carbon-14 (14C) and multi-collector Inductively Coupled Plasma (ICP)-Mass Spectrometry (MS) 234Uranium/230Thorium dating of lake algae and carbonates known to be widespread in the proposed field area.
The Antarctic Ice Sheet is the greatest potential contributor to sea-level change. However, the future response of the ice sheet to warming climate is recognized as one of the greatest uncertainties in sea-level projections. An understanding of past ice fluctuations can afford insight into ice-sheet response to climate change and thus is critical for improving sea-level predictions. In this project, we will reconstruct the behavior of the Antarctic Ice Sheet in the western Ross Sea region during the great global warming that ended the last ice age. Fluctuations in ice volume during this time period will allow us to characterize the factors that cause the ice sheet to advance and retreat and will enable us to distinguish between models that suggest repeated episodes of ice-sheet collapse vs those that indicate ice-sheet growth during warming climate. An understanding of the cause(s) of changes in ice volume during the warming that ended the last ice age has important implications for the future of the Antarctic Ice Sheet.
During November 2018 to January 2019 we carried out an extensive geophysical survey on the Whillans Ice Stream in West Antarctica. Our survey is the first to use magnetotelluric (MT) imaging to map subglacial groundwater water beneath an ice stream. We collected a total of 44 passive MT stations, as well as several active-source electromagnetic (EM) stations using a large loop transmitter system. These data will be used to study the distribution of groundwater at the base of the ice stream at both the grounding line where the ice stream turns into the Ross Ice Shelf and at Whillans Subglacial Lake. We also serviced a few long term GPS stations that have been recording data for several years and that have been used to track transient changes in ice velocity associated with basal water filling and draining in subglacial lakes.
ANDRILL is a scientific drilling program to investigate Antarctica's role in global climate change over the last sixty million years. The approach integrates geophysical surveys, new drilling technology, multidisciplinary core analysis, and ice sheet modeling to address four scientific themes: (1) the history of Antarctica's climate and ice sheets; (2) the evolution of polar biota and ecosystems; (3) the timing and nature of major tectonic and volcanic episodes; and (4) the role of Antarctica in the Earth's ocean-climate system. <br/><br/>This award initiates what may become a long-term program with drilling of two previously inaccessible sediment records beneath the McMurdo Ice Shelf and in South McMurdo Sound. These stratigraphic records cover critical time periods in the development of Antarctica's major ice sheets. The McMurdo Ice Shelf site focuses on the Ross Ice Shelf, whose size is a sensitive indicator of global climate change. It has recently undergone major calving events, and there is evidence of a thousand-kilometer contraction since the last glacial maximum. As a generator of cold bottom water, the shelf may also play a key role in ocean circulation. The core obtained from this site will also offer insight into sub-ice shelf sedimentary, biologic, and oceanographic processes; the history of Ross Island volcanism; and the flexural response of the lithosphere to volcanic loading, which is important for geophysical and tectonic studies of the region.<br/><br/>The South McMurdo Sound site is located adjacent to the Dry Valleys, and focuses on the major ice sheet overlying East Antarctica. A debate persists regarding the stability of this ice sheet. Evidence from the Dry Valleys supports contradictory conclusions; a stable ice sheet for at least the last fifteen million years or an active ice sheet that cycled through expansions and contractions as recently as a few millions of years ago. Constraining this history is critical to deep-time models of global climate change. The sediment cores will be used to construct an overall glacial and interglacial history for the region; including documentation of sea-ice coverage, sea level, terrestrial vegetation, and melt-water discharge events. The core will also provide a general chronostratigraphic framework for regional seismic studies and help unravel the area's complex tectonic history.<br/><br/>The broader impacts of this project include formal and informal education, new research infrastructure, various forms of collaboration, and improving society's understanding of global climate change. Education is supported at the postdoctoral, graduate, undergraduate, and K-12 levels. Teachers and curriculum specialists are integrated into the research program, and a range of video resources will be produced, including a science documentary for television release. New research infrastructure includes equipment for core analysis and ice sheet modeling, as well as development of a unique drilling system to penetrate ice shelves. Drill development and the overall project are co-supported by international collaboration with scientists and the National Antarctic programs of New Zealand, Germany, and Italy. The program also forges new collaborations between research and primarily undergraduate institutions within the United States. <br/><br/>As key factors in sea-level rise and oceanic and atmospheric circulation, Antarctica's ice sheets are important to society's understanding of global climate change. ANDRILL offers new data on marine and terrestrial temperatures, and changes our understanding of extreme climate events like the formation of polar ice caps. Such data are critical to developing accurate models of the Earth's climatic future.
We will measure the surface energy balance on West Antarctica as it relates to atmospheric forcing of surface melt and hydrofracturing of ice shelves and grounding-line ice cliffs. In this program we build upon recent experience with a major campaign jointly supported by the US Antarctic Program (USAP) and US Department of Energy (DOE), the Atmospheric Radiation Measurement (ARM) West Antarctic Radiation Experiment (AWARE). AWARE deployed a highly advanced suite of atmospheric and climate science instrumentation to McMurdo Station from December 2015 through December 2016, including spectral radiometers, research radars and lidars, and comprehensive meteorological equipment. AWARE also deployed a smaller suite of radiometers, lidars, and rawinsonde equipment to the West Antarctic Ice Sheet (WAIS) Divide Ice Camp during December 2015 and January 2016. This project’s principal investigator, Dr. Lubin (Scripps Institution of Oceanography, SIO), was the AWARE lead scientist. For this program we will deploy a suite instruments to measure downwelling and net shortwave and longwave fluxes, sensible and latent heat fluxes, and near-surface meteorology. This suite of instruments will be self-reliant with power requirements and will be supportable in the field with flexible resources, for example a single Twin Otter aircraft mission. These measurements will be analyzed and interpreted to determine synoptic and mesoscale conditions that govern surface melt in West Antarctica, in the context of improving coupled climate model parameterizations.
The research focus of this collaborative proposal was to collect fossil plants, fossil wood, stratigraphic, sedimentologic, paleosol, and geochemical data from plants and the rocks that contain them in order to reconstruct the extent of the Gondwana glaciation in the Shackleton Glacier (SHK) area, the invasion and subsequent flourishing of life following glacial retreat, changes to the physical environment, and the eventual recovery of plant life after the Late Permian biotic events. Only in Antarctica does a complete polar-to-near-polar succession occur across this climatic and biologic transition. The SHK is an important one as it is one of the few regions in the world where the Permian-Triassic boundary (PTB) is exposed within terrestrial rocks. In addition, outcrops in the SHK area extend from the glacigenic deposits of the Upper Carboniferous-Lower Permian through to the Upper Triassic and thus record ecosystems and the plants that inhabited them from the Gondwana icehouse into the Late Permian-Early Triassic greenhouse and into presumed "full recovery" of floras from the PTB extinctions in the Late Triassic.
The project encompassed a multidisciplinary plan that used various types of paleobotanical expertise, integrated with detailed sedimentology, stratigraphy, and geochemistry, in order to reconstruct Permian-Triassic plant communities and their paleoenvironments. This interdisciplinary approach is a powerful tool to uncover details of Antarctica’s complex late Paleozoic and Mesozoic environmental, climatic, and biotic history which included: 1) glaciation/deglaciation, 2) development and evolution of a post-glacial landscape and biota, 3) environmental and biotic change associated with the end-Permian mass extinction events, 4) earliest ecosystems in the Triassic, 5) greenhouse conditions in the Triassic, 6) full ’recovery’ of floras and ecosystems by the Late Triassic, and, through all of these events, 7) development and changes in a foreland basin system. Three interrelated focus areas, each delimited by distinct hypotheses and action strategies, provided the framework to trace floral diversity and environmental evolution after the retreat of glaciers through to the Late Triassic. Antarctica is the only place on Earth that includes extensive outcrops of high-paleolatitude terrestrial rocks, combined with widespread and well-preserved plant fossils, and that spans this crucial time.
The research and broader impacts of this proposal were integrated into action strategies that have been successful in the past. Compression floras were collected (constrained by stratigraphy) both quantitatively and qualitatively in order to obtain biodiversity and abundance data, and as a data source for paleoecological analysis. Even in formations where megafossils were unknown (e.g., Lower Permian), fossil wood is present so that anatomy and geochemistry of tree rings were examined. Standard sedimentologic and stratigraphic analyses were performed, as well as paleosol analyses, including mineralogic and major- and trace-element geochemistry. Collections will also be made for U-Pb zircon geochronology to better constrain geologic and biotic events.
The Broader Impacts of the project involved education and outreach initiatives that included women and under-represented groups in the excitement of Antarctic earth sciences: 1) Continuing successful public outreach, teaching, and mentoring of women and under-represented students in Antarctic research; 2) Participation in workshops for under-represented groups via the Expanding Your Horizons Program in Kansas, the TRIO program (KU), and the STELAR summer workshop (UWM) for high-school students. 3) Outreach via the KU Natural History Museum; 4) Exploring Antarctic geosciences through continued presentations to pre K-12 school groups, and field and lab activities at UWM, as well as links from McMurdo Station and satellite conferences from the field with K-12 science classes in Wisconsin and Illinois.
The McMurdo Dry Valleys are the largest ice-free region in Antarctica and home to a seasonally active hydrologic system, with streams and saline lakes. Streams are fed by summer meltwater from local glaciers and snowbanks. Therefore, streamflow is tied to summer climate conditions such as air temperatures, ground temperatures, winds, and incoming solar radiation. Based on 50 years of monitoring, summer stream activity has been observed to change, and it likely varied during the geologic past in response to regional climate change and fluctuating glaciers. Thus, deposits from these streams can address questions about past climate, meltwater, and lake level changes in this region. How did meltwater streamflow respond to past climate change? How did streamflow vary during periods of glacial advance and retreat? At what times did large lakes fill many of the valleys and what was their extent? The researchers plan to acquire a record of stream activity for the Dry Valleys that will span the three largest valleys and a time period of about 100,000 years. This record will come from a series of active and ancient alluvial fans that were deposited by streams as they flowed from valley sidewalls onto valley floors. The study will provide a long-term context with which to assess recent observed changes to stream activity and lake levels. The research will be led by two female mid-career investigators and contribute significantly to student research opportunities and education. The research will contribute to graduate and undergraduate education by including students in both field and laboratory research, as well as incorporating data and results into the classroom. The research will be disseminated to K-12 and non-scientific communities through outreach that includes professional development training for K-12 teachers in eastern Massachusetts, development of hands-on activities, visits to K-12 classrooms, and STEM education and literacy activities in North Carolina.
The PIs propose to constrain rates of fluvial deposition and periods of increased fluvial activity in the McMurdo Dry Valleys during the Holocene and late Pleistocene. During 50 years of hydrologic monitoring in the Dry Valleys, scientists have observed that streams exhibit significant response to summer conditions. Previous studies of glacial and lacustrine deposits indicate regional glacier advance in the Dry Valleys during recent interglacial periods and high lake levels during and after the Last Glacial Maximum (LGM), with potentially significant low and high stands during the Holocene. However, the geologic record of meltwater activity is poorly constrained. The PIs seek to develop the first spatially-extensive record of stream deposition in the Dry Valleys by analyzing and dating alluvial fans. Given that alluvial fans are deposited by summer meltwater streams in a relatively stable tectonic setting, this record will serve as a proxy of regional summer climate conditions. Meltwater streams are an important component of the regional hydrologic system, connecting glaciers to lakes and affecting ecosystems and soils. A record of fluvial deposition is key to understanding the relationship between past climate change and regional hydrology. The proposed research will include remote- and field-based mapping of alluvial fans, stream channels, and meltwater sources as well as modeling potential incoming solar radiation to the fans and moisture sources during the austral summer. In the field, the PIs will document stratigraphy, collect near-surface sediments from 25 fans across four valleys (Taylor, Pearse, Wright, and Victoria), and collect 2- to 3-m vertical cores of ice-cemented sediments from three alluvial fan complexes. The PIs will then conduct depositional dating of fluvial sands via optically stimulated luminescence, and analyze mineralogy and bulk major element chemistry with X-ray powder diffraction and X-ray fluorescence. From these analyses, the PIs propose to (1) determine the timing of local- to regional-scale periods of high fluvial deposition, (2) calculate depositional rates, and (3) constrain depositional environments and sediment provenance. Given that many of the alluvial fans occur below the hypothesized maximum extents of glacially-dammed lakes in Wright and Victoria valleys, detailed stratigraphy, sediment provenance, and OSL dating of these fans could shed light on ongoing debates regarding the timing and extent of LGM and post-LGM lakes. The work will support a postdoctoral researcher, a PhD student, and many undergraduate and master’s students in cross-disciplinary research that spans stratigraphy, geochemistry, paleoclimatology and physics.
Overview: We aim to provide the most detailed investigation to date of the factors that influence predictability of Antarctic climate, the coupling of climate to penguins populations, and the integration of the two to optimize ecological forecasts. This integrated understanding is critical for guiding future ecological and climate research, prioritizing bio-physical monitoring efforts, and informing conservation decision-making. Our study will reveal the influence of climate system dynamics on ecological predictability across a range of scales and will examine how this role differs among ecological processes, species and regions of Antarctica.
Intellectual Merit: Many biophysical processes will change in the coming century. Yet, the mechanisms controlling the predictability of many climate processes are still poorly understood, limiting progress in climate forecasting. In parallel, ecological forecasting remains a nascent discipline. In particular, comparative assessments of predictability, both within and among species, are critically needed to understand the factors that allow (or prevent) useful ecological forecasts. While important for ecological science generally, this need is particularly pressing in Antarctica where the environment is highly dynamic, strongly coupled to biological processes, and likely to change in the future. Improved ecological forecasting therefore requires interdisciplinary efforts to understand the causes of predictability in climate, and in tandem, how climate influences the predictability of natural populations.
This proposed research will examine the predictability of Antarctic climate and its influence on penguin demographic response predictability at various temporal and spatial scales using the longest datasets available for two penguin species. Specifically, the PI will 1) identify the physical mechanisms giving rise to climate predictability in Antarctica, 2) identify the relationships between climate and ecological processes at a range of scales, and 3) reveal the factors controlling ecological predictability across a range of scales (e.g., those relevant for short-term adaptive management versus those relevant at end-of-century timescales). These objectives will be achieved using the analysis of existing climate data and Atmosphere-Ocean Global Circulation Models (AGOCMs), with coupled analysis of existing long-term demographic data for multiple seabird species that span a range of ecological niches, life histories, and study sites across the continent.
Overview: To date, studies that have addressed the impacts of global changes have mainly focused on linking climate variability and/or human disturbances to individual life history traits, population dynamics or distribution. However, individual behavior and plasticity mediate these responses. The goal of this project is to understand mechanisms linking environmental changes (climate & fisheries)- behavioral personality type – plasticity in foraging behaviors- life history traits – population dynamics for a seabird breeding in the southern ocean: the wandering albatross. This project will also forecast the population structure and growth rate using the most detailed mechanistic model to date for any wild species incorporating behaviors in an eco-evolutionary context. Specifically, the investigators will (1) characterize the life history strategies along the shy-bold continuum of personalities and across environmental conditions; (2) understand the link between phenotypic plasticity in foraging effort and personality; (3) characterize the heritability of personality and foraging behaviors; (4) develop a stochastic eco-evolutionary model to understand and forecast the distribution of bold and shy individuals within the population and the resulting effect on population growth rate in a changing environment by integrating processes from goals 1, 2 and 3. To date, this has been hampered by the lack of long-term data on personality and life histories in any long-lived species in the wild. For the first time ever, we have tested in a controlled environment the response to a novel situation for ~1800 individuals for more than a decade to define individual personality variation along the shy-bold continuum that we can relate to the life history traits over the entire species life cycle using unique long-term individual mark-recapture data sets for this iconic polar species. The novelty of this project thus lies in the combination of personality, foraging and demographic data to understand and forecast population responses to global change using state-of-the-art statistical analysis and eco-evolutionary modeling approaches.
Intellectual Merit: While there is ubiquitous evidence of personality differences across taxa, the implications for life-history are less clear, and the consequences for population dynamics virtually unexplored empirically. How the phenotypic distributions of personality and foraging behaviors types within a population is created and maintained by ecological (demographic and phenotypic plasticity) and evolutionary (heritability) processes remain an open question. Personality traits are a crucial link between how individuals acquire resources, and how they allocate these to reproduction and survival, and this trade-off drives population dynamics. However, although some studies have found different foraging behaviors or breeding performances between personality types, none have established the link between personality- foraging behaviors – life histories (both reproduction and survival, and their covariations) in the context of climate change. Furthermore plasticity in foraging behaviors is not considered in the pace-of-life syndrome, which has potentially hampered our ability to find covariation between personality and life history trade-off. Research into the heritability of personality traits has revealed a strong heritable component, but studies looking at the heritability of foraging behaviors are lacking. For the first time ever, this project will fill these knowledge gaps and integrate in an eco-evolutionary model the complex interaction among individual personality and foraging plasticity, heritability of personality and foraging behaviors, life history strategies, population dynamics in a changing environment (fisheries and climate). Furthermore, this project will provide for the first time projections of population size and structure under future global change using state-of-the-art climate projections from IPCC-class atmospheric-oceanic global circulation models.
Part I: Non-technical description:
The Ross Sea, a globally important ecological hotspot, hosts 25-45% of the world populations of Adélie and emperor penguins, South Polar skuas, Antarctic petrels, and Weddell seals. It is also one of the few marine protected areas designated within the Southern Ocean, designed to protect the workings of its ecosystem. To achieve that goal requires participation in an international research and monitoring program, and more importantly integration of what is known about these mesopredators, which is a lot, and the biological oceanography of their habitat, parts of which are also well known. The project will acquire data on these species’ food web dynamics through assessing of Adélie penguin foraging behavior, an indicator species, while multi-sensor ocean gliders autonomously quantify prey abundance and distribution as well as ocean properties, including phytoplankton, at the base of the food web. Additionally, satellite imagery will quantify sea ice and whales (competitors) within the penguins’ foraging area. Seasoned researchers and students will be involved, as will a public outreach program that reaches >200 school groups per field season, and >1M visits to the website of an ongoing, related project. Lessons about ecosystem change, and how it is measured, i.e. the STEM fields, will be emphasized. Results will be distributed to the world science and management communities.
Part II: Technical description:
This project, in collaboration with the National Environmental Research Council (UK), assesses food web structure in the southwestern Ross Sea, a major portion of the recently designated Ross Sea Region Marine Protected Area, designed to protect the region’s “food web structure, dynamics and function.” Success requires in-depth, integated ecological information. The western Ross Sea, especially the marginal ice zone of the Ross Sea Polynya (RSP), supports global populations of iconic and indicator species: 25% of emperor penguins, 30% of Adélie penguins, 50% of South Polar skuas, and 45% of Weddell seals. However, while individually well researched, for these members of the upper food web information has been poorly integrated into understanding of Ross Sea food web dynamics and biogeochemistry. Information from multi-sensor ocean gliders, high-resolution satellite imagery, diet analysis and biologging of penguins, when integrated will facilitate understanding of the preyscape within the intensively investigated biogeochemistry of the RSP. UK participation covers a number of glider functions (e.g., providing a state-of-the-art glider at minimal cost, glider programming, ballasting, and operation) and supplies expertise to evaluate the oceanographic conditions of the study area. Several student will be involved, as well as an existing outreach program in a related penguin research project reaching annually >200 school groups and >1M website visits.
The goals of this collaborative project are to merge empirical observations from the deglaciated Antarctic continental shelf and 1-D and 3-D numerical model experiments to test the sensitivity of marine-based ice sheets to subglacial topography with collaborators at the University of Kansas (L. Stearns, C. van der Veen). We focus on five glacial systems (i.e., flowlines) across the Amundsen Sea, Ross Sea, and George V Coast of Wilkes Land that extended to/near the continental shelf break at the Last Glacial Maximum – with a range of bed characteristics, topographic features, oceanographic and climatic conditions, and patterns of past ice flow and grounding line retreat. Specifically, at the University of Virginia, we (L. Simkins, S. Munevar Garcia) are: (ongoing) exploring bed roughness across the flowlines to determine the sensitivity of ice flow and grounding line behavior to different scales and wavelengths of bed topography/roughness; (upcoming) developing an empirical relationship between ice-marginal landform sediment volume and grounding line occupation time, and combining this with sedimentological analyses and new absolute age constraints to produce more comprehensive timelines of grounding line retreat, influential boundary conditions and processes, and determine the presence/absence of ice shelves; (ongoing) integrating quantitative and qualitative paleo- and offshore data to be incorporated into and/or validate 1-D and 3-D model experiments further testing the sensitivity of the five glacial systems to bed topography; and (completed) co-developing community engagement and education materials that focus on merging paleo-observations and model information of the Antarctic Ice Sheet from the LGM to the present
Overview:
The ice cover of Antarctica is changing rapidly, and some reports already suggest we are at, or possibly beyond, the tipping point for the Western Antarctic Ice Sheet collapse. Loss of this ice sheet will have profound effects on marine fauna, including dramatically changing habitat availability for benthic marine species in the Southern Ocean. Formation and collapse of the Western Antarctic Ice Sheet is a cyclical process suggesting that we can learn how fauna respond to ice loss by examining historical climate conditions. Evidence from sediment cores suggests a near complete collapse occurred ~1.1 MYA and modeling suggests a collapse as recent at 125 KYA. During such periods, transantarctic seaways connected the Ross and Weddell Seas. Interestingly, most theories regarding marine invertebrate distributions around the Antarctic focus on dispersal by the Antarctic Circumpolar Current or population bottlenecks and expansions generated by repeated cycles of glaciation and fail to account for transcontinental seaways. Although the impact of previous seaways on genetic structure of present-day populations has been largely ignored, a growing body of data reveal historical connections between Ross and Weddell invertebrate communities, suggesting historical dispersal between these present-day disconnected and distant basins. Future ice shelf collapses will likely reestablish such connections causing redistribution of marine taxa. By exploring alternative hypotheses about the factors that may have shaped patterns of biodiversity in the last couple of million years, our proposed work will aid prediction of possible changes that may, or may not, occur as the Antarctic ice sheets continue to deteriorate.
Intellectual Merit:
The overarching goal of this research is to understand environmental factors that have shaped patterns of present-day diversity in Antarctic benthic marine invertebrates. Building on our previous work examining circumpolar distributions of multiple marine benthic invertebrate, we are particularly interested in assessing if transantarctic waterways may help explain observed similarities between the Ross and Weddell Seas better than other possible explanations (e.g., dispersal by the Antarctic Circumpolar Current, or expansion from common glacial refugia). To this end, we will employ population genomic approaches using Single Nucleotide Polymorphism (SNP) markers that sample thousands of loci across the genome. Building on our previous phylogeographic studies, we will target 7 Antarctic benthic invertebrate taxa to test alternative hypothesis accounting for population genetic structure. Additionally, the current paradigm is that divergence between closely related, often cryptic, species is the result of genetic drift due to population bottlenecks caused by glaciation. We will directly test this assumption by mapping SNP data on to draft genomes of three of our target taxa to assess the degree of genetic divergence and look for signs of selection. If linkage groups under selection are found, we will examine cellular mechanisms under selection. Thus, our research directly addresses NSF programmatic goals to understand how Antarctic biota evolve and adapt.
Broader Impacts:
Our approach will test several hypotheses that dominate the current understanding of marine biodiversity patterns in the Antarctic providing relevance to several fields of Antarctic science. Also, there are implications for understanding and predicting effects of future ice shelf collapse. The PIs are committed to developing the next generation of researchers and actively engage underrepresented groups at all career stages. We expect to train a minimum of 4 graduate students, a postdoc and several undergraduates on this project. This work will include several specific outreach activities including continuation of our past social media efforts with cruise blogs which were accessed by several thousand unique IP addresses and presentations in K-8 classrooms that reach about 300+ children a year. We also propose to develop 15-20 short YouTube videos on Antarctic genomics as outreach products, we will conduct a photo exhibition, and we will develop two 3-day workshops aimed at students to introduce them to bioinformatics approaches. These works will have formal assessment.
This proposal requires fieldwork in the Antarctic.
Ice shelves play a critical role in restricting the seaward flow of grounded ice by providing buttressing at their bases and sides. Processes that affect the long-term stability of ice shelves can therefore impact the future contribution of the Antarctic Ice Sheet to global sea-level rise. Ross Ice Shelf is the largest ice shelf on Earth, and it buttresses massive areas of West and East Antarctica. Previous studies of modern ice velocity indicate that Ross Ice Shelf’s mass loss is roughly balanced by its mass gain. However, more recent remote sensing observations extended further back in time reveal the ice shelf is likely not in steady-state, including possible long-term thinning since the late 90s. Therefore, to accurately interpret modern days ice shelf changes, long-term observations are critical to evaluate how these short-term variations fit into the historical context of ice shelf variability. This project examines over four decades (1971 – 2017) of historical and modern airborne radar sounding observations of the Ross Ice Shelf to investigate ice-shelf changes on the decadal timescales. The researchers will process, calibrate, and analyze radar data collected during the 1971-79 SPRI/NSF/TUD campaign and compare them against modern observations from both the 2011-17 NASA Operation IceBridge/NSF CReSIS and the 2015-17 ROSETTA-Ice surveys. They will estimate basal melt rates by examining changes in ice-shelf thickness. They will determine other important basal melt metrics, including ice shelf roughness, englacial temperature, and marine ice formation. This project will support the education of a Ph.D. student from each of the institutions. This project will also support the training of undergraduate and high school researchers more generally in the field of radioglaciology and Antarctic sciences.
Nontechnical Description
The Antarctic core collection, curated at Florida State University since 1963, is one of the world's premier marine geology collections. Consisting of irreplaceable sediment cores, this archive has greatly advanced the understanding of the Earth system, past and present, and will remain critical to future studies of the Earth. Given Oregon State University's (OSU) leadership in marine research and long track record providing state-of-the-art curatorial services through the OSU Marine and Geology Repository, this facility will provide world-class curatorial stewardship of the Antarctic core collection for decades to come. The Antarctic core collection will be co-located and co-managed with the current OSU collection in a single modern repository and analytical facility. The combined collection will contain more than 30 km of refrigerated sediment core from the world's oceans and will be housed in a new 33,000 SFT facility purchased in 2009 by OSU and upgraded in 2016-17. The total refrigerated space can hold both collections comfortably and has at least five decades of expansion space.
The co-location and co-management of these two collections, paired with a modern suite of analytical facilities, will lead to greater collaboration, cross-pollination of ideas, and availability of enhanced technical services and capabilities for a growing user group that increasingly relies on marine sediments. The facility will employ a comprehensive community interaction plan that takes advantage of the new OSU Marine and Geology Repository building with a 32-person seminar room, its large 1,044 square foot core lab, and ten adjoining analytical laboratories, which will provide scientific and experiential learning opportunities for students, the general public, and the Earth Sciences research community. The facility will organize small group meetings, sampling parties and summer schools that will complement ongoing support for teaching, training and learning through the use of the repository in graduate, undergraduate, and K-12 classes and Research Experience for Undergraduate programs. The repository is open to the general public for tours and presentations, and the data products derived from the facility will be disseminated via the repository website at http://osu-mgr.org/ and other national databases.
Technical Description
The Antarctic and the Southern Ocean National Collection of Rock and Sediment Cores currently housed at Florida State University will be relocated to Oregon State University (OSU) and housed along with the OSU Marine and Geology Repository. Oregon State University investigators will co-manage the Antarctic core collection and the Marine and Geology Repository as a single modern repository and analytical facility. The combined collection will be housed a new 33,000 square foot building with refrigerated space that can hold both collections with approximately five decades of expansion space. The co-location and co-management of these two collections offers unique curatorial synergies, cost savings, and improved capabilities to support both the research and educational needs of a wider marine and Antarctic communities. The facility will house a 32-person seminar room, a large 1,044 square foot core lab that allows layout, inspection and examination of cores, and adjoining analytical laboratories that will provide quantitative analysis as well as experiential learning opportunities for students.
Rapid and persistent climate warming in the Western Antarctic Peninsula is likely resulting in intensified snow-algae growth and an extended bloom season in coastal areas. Similarly, deposition of light absorbing particles (LAPs) onto Antarctica cryosphere surfaces, such as black carbon from intensifying Southern Hemisphere wildfire seasons, and dust from the expansion of ice-free regions in the Antarctic Peninsula, may be increasing. The presence of snow algae blooms and LAPs enhance the absorption of solar radiation by snow and ice surfaces. This positive feedback creates a measurable radiative forcing, which can have immediate local and long-term regional impacts on albedo, snow melt and downstream ecosystems. This project will investigate the spatial and temporal distribution of snow algae, black carbon and dust across the Western Antarctica Peninsula region, their response to climate warming, and their role in regional snow and ice melt. Data will be collected across multiple spatial scales from in situ field measurements and sample collection to imagery from ground-based photos and high resolution multi-spectral satellite sensors. Ground measurements will inform development and application of novel algorithms to map algal bloom extent through time using 0.5-3m spatial resolution multi-spectral satellite imagery. Results will be used to improve snow algae parameterization in a new version of the Snow Ice Aerosol Radiation model (SNICARv3) that includes bio-albedo feedbacks, eventually informing models of ice-free area expansion through incorporation of SNICARv3 in the Community Earth System Model. Citizen scientists will be mentored and engaged in the research through an active partnership with the International Association of Antarctic Tour Operators that frequently visits the region. The cruise ship association will facilitate sampling to develop a unique snow algae observing network to validate remote sensing algorithms that map snow algae with high-resolution multi-spectral satellite imagery from space. These time-series will inform instantaneous and interannual radiative forcing calculations to assess impacts of snow algae and LAPs on regional snow melt. Quantifying the spatio-temporal growing season of snow algae and impacts from black carbon and dust will increase our ability to model their impact on snow melt, regional climate warming and ice-free expansion in the Antarctic Peninsula region.
The potential for future sea level rise from melting and collapse of Antarctic ice sheets and glaciers is concerning. We can improve our understanding of how water is exchanged between Antarctic ice sheets and the ocean by studying how ice sheets behaved in past climates, especially conditions that were similar to or warmer than those at present. For this project, the research team will document Antarctica’s response across an interval when Earth transitioned from the warm Pliocene into the Pleistocene ice ages by combining marine and land evidence for glacier variations from sites near the Antarctic Peninsula, complimented by detailed work on timescales and fossil evidence for environmental change. An important goal is to test whether Antarctica’s glaciers changed at the same time as glaciers in the Northern Hemisphere as Earth's most recent Ice Age intensified, or alternatively responded to regional climate forcing in the Southern Hemisphere. Eleven investigators from seven US institutions, as well as Argentine collaborators, will study new sediment cores from the International Ocean Discovery Program, as well as legacy cores from that program and on-land outcrops on James Ross Island. The group embraces a vertically integrated research program that allows high school, undergraduate, graduate, post-docs and faculty to work together on the same projects. This structure leverages the benefits of near-peer mentoring and the development of a robust collaborative research network while allowing all participants to take ownership of different parts of the project. All members of the team are firmly committed to attracting researchers from under-represented groups and will do this through existing channels as well as via co-creating programming that centers the perspectives of diverse students in conversations about sea-level rise and climate change.
The proposed research seeks to understand phasing between Northern and Southern Hemisphere glacier and climate changes, as a means to understand drivers and teleconnections. The dynamics of past Antarctic glaciation can be studied using the unique isotope geochemical and mineralogic fingerprints from glacial sectors tied to a well-constrained time model for the stratigraphic successions. The proposed work would further refine the stratigraphic context through coupled biostratigraphic and magnetostratigraphic work. The magnitude of iceberg calving and paths of icebergs will be revealed using the flux, geochemical and mineralogic signatures, and 40Ar/39Ar and U-Pb geochronology of ice-rafted detritus. These provenance tracers will establish which sectors of Antarctica’s ice sheets are more vulnerable to collapse, and the timing and pacing of these events will be revealed by their stratigraphic context. Additionally, the team will work with Argentine collaborators to connect the marine and terrestrial records by studying glacier records intercalated with volcanic flows on James Ross Island. These new constraints will be integrated with a state of the art ice-sheet model to link changes in ice dynamics with their underlying causes. Together, these tight stratigraphic constraints, geochemical signatures, and ice-sheet model simulations will provide a means to compare to the global records of climate change, understand their primary drivers, and elucidate the role of the Antarctic ice sheet in a major, global climatic shift from the Pliocene into the Pleistocene.
The project targets scientific questions recently formulated by the community during the 2016 NSF-sponsored Scientific Drivers and Future of Mount Erebus Volcano Observatory workshop. The location and geometry of the magmatic plumbing from vent to lower crust system remain poorly constrained, particularly below 1 km depth. The style and causes for changes in volcanic and magmatic activity over the short term (minutes to hours) and on the decadal scale remains enigmatic. Two decades of campaign and continuous GPS data on Ross Island provide insights into the longer term dynamics of both, Ross Island growing within the Terror Rift, and Erebus' deeper magmatic system. We organized and analyzed all existing GPS data for Ross Island, and interpreted anomalies in the resulting time series. The GPS data were consistently processed and interpreted. We generated position time series in a consistent reference frame and make the results available to the community. We find several periods of volcanic transient deformation in the time series, indicating times of inflation before 2004, deflation from 2004-2011 and renewed inflation from October 2020 until June 2021.
The project targets the long-term variability of the West Antarctic Ice Sheet over several glacial-interglacial cycles in the early Pliocene sedimentary record drilled by the International Ocean Discovery Program (IODP) Expedition 379 in the Amundsen Sea. Data collection includes 1) the sand provenance of ice-rafted debris and shelf diamictites and its sources within the Amundsen Sea and Antarctic Peninsula region; 2) sedimentary structures and sortable silt calculations from particle size records and reconstructions of current intensities and interactions; and 3) the bulk provenance of continental rise sediments compared to existing data from the Amundsen Sea shelf with investigations into downslope currents as pathways for Antarctic Bottom Water formation. The results are analyzed within a cyclostratigraphic framework of reflectance spectroscopy and colorimetry (RSC) and X-ray fluorescence scanner (XRF) data to gain insight into orbital forcing of the high-latitude processes. The early Pliocene Climatic Optimum (PCO) ~4.5-4.1 Ma spans a major warm period recognized in deep-sea stable isotope and sea-surface temperature records. This period also coincides with a global mean sea level highstand of > 20 m requiring contributions in ice mass loss from Antarctica. The following hypotheses will be tested: 1) that the West Antarctic Ice Sheet retreated from the continental shelf break through an increase in sub iceshelf melt and iceberg calving at the onset of the PCO ~4.5 Ma, and 2) that dense shelf water cascaded down through slope channels after ~4.5 Ma as the continental shelf became exposed during glacial terminations. The project will reveal for the first time how the West Antarctic Ice Sheet operated in a warmer climate state prior to the onset of the current “icehouse” period ~3.3 Ma.
Due to persistent cold temperatures, geographical isolation, and resulting evolutionary distinctness of Southern Ocean fauna, the study of Antarctic reducing habitats has the potential to fundamentally alter our understanding of the biologic processes that inhibit greenhouse gas emissions from our oceans. Marine methane, a greenhouse gas 25x as potent as carbon dioxide for warming our atmosphere, is currently a minor component of atmospheric forcing due to the microbial oxidation of methane within the oceans. Based on studies of persistent deep-sea seeps at mid- and northern latitudes we have learned that bacteria and archaea create a ‘sediment filter’ that oxidizes methane prior to its release. As increasing global temperatures have and will continue to alter the rate and variance of methane release, the ability of the microbial filter to respond to fluctuations in methane cycles is a critical yet unexplored avenue of research. Antarctica contains vast reservoirs of methane, equivalent to all of the permafrost in the Arctic, and yet we know almost nothing about the fauna that may mitigate its release, as until recently, we had not discovered an active methane seep.
In 2012, a methane seep was discovered in the Ross Sea, Antarctica that formed in 2011 providing the first opportunity to study an active Antarctic methane-fueled habitat and simultaneously the impact of microbial succession on the oxidation of methane, a critical ecosystem service. Previous work has shown that after 5 years of seepage, the community was at an early stage of succession and unable to mitigate the release of methane from the seafloor. In addition, additional areas of seepage had begun nearby. This research aims to quantify the community trajectory of these seeps in relation to their role in the Antarctic Ecosystem, from greenhouse gas mitigation through supporting the food web. Through the application of genomic and transcriptomic approaches, taxa involved in methane cycling and genes activated by the addition of methane will be identified and contrasted with those from other geographical locations. These comparisons will elucidate how taxa have evolved and adapted to the polar environment.
This research uses a ‘genome to ecosystem’ approach to advance our understanding of organismal and systems ecology in Antarctica. By quantifying the trajectory of community succession following the onset of methane emission, the research will decipher temporal shifts in biodiversity/ecosystem function relationships. Phylogenomic approaches focusing on taxa involved in methane cycling will advance the burgeoning field of microbial biogeography on a continent where earth’s history may have had a profound yet unquantified impact on microbial evolution. Further, the research will empirically quantify the role of chemosynthesis as a form of export production from seeps and in non-seep habitats in the nearshore Ross Sea benthos, informing our understanding of Antarctic carbon cycling.
Albatrosses (family Diomedeidae) are among the most threatened of bird species. Of the 22 species that are currently recognized, all are considered at least Threatened or Near-Threatened, and 9 are listed as Endangered or Critically Endangered. Because of the decline in albatross populations and the birds' role as a top predator in the pelagic ecosystem, it is vitally important to understand the factors affecting the population dynamics of these birds to better inform strategies for conservation and mitigating environmental change. The goal of this project is to answer the question: What are the population consequences of albatross bioenergetics and foraging strategies? The project took a two pronged approach: 1) constructing, parameterizing, and validating a Dynamic Energy Budget model to understand growth and constraints on foraging; and 2) undertaking an in-depth meta-analysis of existing individual tracking and life history data from multiple albatross species across successive life stages. This theoretical work will be grounded with a unique and extensive data set on albatrosses provided by collaborator Richard Phillips from the British Antarctic Survey. Bioenergetics constrain a variety of behaviors. A more complete understanding of how individuals use energy can give insight into how behaviors from foraging to breeding and survival, and resulting population attributes, might change with environmental factors, due to anthropogenic and other drivers. This work will further a general understanding of how bioenergetics shapes behavior and drives population level processes, while providing an approach that can be used to guide conservation strategies for endangered populations. The research findings and activities were made accessible to public audiences through websites and a blog maintained for the project by a postdoctoral researcher. The project involved undergraduate researchers in the project, within formal laboratory groups and also through in-classroom presentations and activities. This project also involved public outreach through twitter and other venues. All project publications are open access, the resulting open source software was released to the public, and metadata and analyses are fully documented to promote further collaborative exploration of this system.
This project fits within the second of three major themes identified by the National Academy of Science report “A Strategic Vision for NSF Investments in Antarctic and Southern Ocean Research”. How do Antarctic biota evolve and adapt to the changing environment? Decoding the genomic and transcriptomic bases of biological adaptation and response across Antarctic organisms and ecosystems. Central in this theme is the physiological capacity of animals to cope with changes in environmental conditions over their lifetime, which this research firmly addresses. In the Southern Ocean surrounding Antarctica there is an extraordinary diversity of marine life. Much of our understanding of the biology of these animals comes from studies of the adaptations of these animals to sub-zero ocean conditions. Antarctic marine organisms have evolved to survive in stable, cold ocean conditions and possess a limited capacity to respond to environmental change. Research to date on Antarctic fishes has focused on adult life stages with much less research on early life stages that likely prioritize growth and development and not physiological mechanisms of stress tolerance. This project addresses the mechanisms that early life stages (embryos, larvae and juveniles) of Antarctic fishes use to respond to changes in ocean conditions. Specifically, the project will examine energetic trade-offs between key developmental processes in the context of environmental change. While the project focuses on Antarctic species, the research is highly translatable to stress tolerance mechanisms of fishes along the coast of North America, many of which are also experiencing changes in multiple environmental factors. Research in the Antarctic allows scientists to identify unifying themes or generalities in physiology that extend beyond the waters of the Southern Ocean and therefore have broad implications for understanding what is limiting the performance of fishes globally. BROADER IMPACTS –To build environmental stewardship and awareness, we must increase science literacy in the broader community. This project does this through three main objectives. First is to increase the diversity of students involved in environmental science research. Student diversity, in turn, gives the scientific community a broader perspective for addressing critical challenges in environmental biology. This project provides resources to support three PhD students, one postdoctoral scholar and two undergraduate students and promotes the diversity of young scientists and the advancement of groups traditionally underrepresented in environmental biology. Todgham will broaden the outreach effort by developing exhibits on environmental change impacts on polar regions for large public events, an opportunity to engage K-12 students, government officials in Sacramento and local and statewide communities. Lastly, through a collaboration with PolarTREC and teacher Denise Hardoy, lesson plans have been developed to teach K-12 students about experimental design, polar environments and sensitivity of Antarctic species to climate change.
An archive of baleen plates from 800 Antarctic blue and fin whales harvested between 1946 and 1948 was recently rediscovered in the Smithsonian’s National Museum of Natural History. As baleen grows, it incorporates compounds from the whale’s diet and surroundings, recording continuous biological and oceanographic information across multiple years. The baleen record forms an ideal experimental platform for studying bottom-up, top-down and anthropogenic impacts on blue and fin whales. Such insights are likely impossible to obtain through any other means as blue and fin whales now number ~1 and 4% of their pre-whaling abundances. The baleen archive includes years with strong climate and temperature anomalies allowing the influence of climate variability on predators and the ecosystems that support them to be examined. Additionally, the impact of whaling on whale stress levels will be investigated by comparing years of intensive whaling with the non-whaling years of WWII, both of which are captured in the time series. We will use 1) bulk stable isotopes to examine the trophic dynamics of Antarctic blue and fin whales, 2) compound-specific stable isotope analysis (CSIA-AA) to characterize the biogeochemistry of the base of the Antarctic food web and 3) hormone analyses to examine the population biology of these species. These investigations will fill major gaps in our understanding of the largest krill predators, their response to disturbance and environmental change, and the impact that commercial whaling has had on the structure and function of the Antarctic marine ecosystem.
This proposal will provide genetic and enzymatic insight into how microbial communities in benthic sediments on the coastal shelf of Antarctica degrade complex organic matter. The current understanding of how benthic microbial communities respond and also degrade complex organic matter in Antarctica is fragmented. Recent work suggests benthic microbial communities are shaped by organic matter availability (encompassing both quantity and quality), however, these studies were observational and did not directly examine community function (e.g. enzyme activity and/or gene expression). Preliminary metagenomic data, collected from western Antarctica marine sediments, document gene potential for organic matter degradation throughout the entire sample set (spanning the Amundsen Sea, Bellingshausen Sea, and Ross Sea), but functional data was not collected. To date, studies have examined either enzyme activity or metagenomic potential but few have been able to directly connect the two. To address these gaps in knowledge, this proposal will utilize powerful tools such as metagenomics and metatranscriptomics, coupled with microcosm experiments, enzyme assays, and geochemical data. This hypothesis driven proposal will examine microbial communities from the continental shelf of Antarctica from two different regions (Bransfield Strait and Weddell Sea) to document the communities’ enzymatic activity and genes used to degrade complex organic matter. These data will expand our current knowledge of genetic potential towards a more direct understanding of enzyme function as it relates to degradation of complex organic matter in marine sediments from Antarctica.
This project will identify behavioral and physiological variability in foraging Emperor Penguins that can be directly linked to individual success in the marine environment using an optimal foraging theory framework during two critical life history stages. First, this project will investigate the foraging energetics, ecology, and habitat use of Emperor Penguins at Cape Crozier using fine-scale movement and video data loggers during late chick-rearing, an energetically demanding life history phase. Specifically, this study will 1) Estimate the foraging efficiency and examine its relationship to foraging behavior and diet using an optimal foraging theory framework to identify what environmental or physiological constraints influence foraging behavior; 2) Investigate the inter- and intra-individual behavioral variability exhibited by emperor penguins, which is essential to predict how resilient they will be to climate change; and 3) Integrate penguin foraging efficiency data with environmental data to identify important habitat. Next the researchers will study the ecology and habitat preference after the molt and through early reproduction using satellite-linked data loggers. The researchers will: 1) Investigate the inter- and intra-individual behavioral variability exhibited by Emperor Penguins during the three-month post-molt and early winter foraging trips; and 2) Integrate penguin behavioral data with environmental data to identify which environmental features are indicative of habitat preference when penguins are not constrained to returning to the colony to feed a chick. These fine- and coarse-scale data will be combined with climate predictions to create predictive habitat models. The education objectives of this CAREER project are designed to inspire, engage, and train the next generation of scientists using the data and video generated while investigating Emperor Penguins in the Antarctic ecosystem. This includes development of two courses (general education and advanced techniques), training of undergraduate and graduate students, and a collaboration with the NSF funded “Polar Literacy: A model for youth engagement and learning” program to develop afterschool and camp curriculum that target underserved and underrepresented groups.
This project on emperor penguin populations will quantify penguin presence/absence, and colony size and trajectory, across the entire Antarctic continent using high-resolution satellite imagery. For a subset of the colonies, population estimates derived from high-resolution satellite images will be compared with those determined by aerial surveys - these results have been uploaded to MAPPPD (penguinmap.com) and are freely available for use. This validated information will be used to determine population estimates for all emperor penguin colonies through iterations of supervised classification and maximum likelihood calculations on the high-resolution imagery. The effect of spatial, geophysical, and environmental variables on population size and decadal-scale trends will be assessed using generalized linear models. This research will result in a first ever empirical result for emperor penguin population trends and habitat suitability, and will leverage currently-funded NSF infrastructure and hosting sites to publish results in near-real time to the public.
The Ross Island region of Antarctica is a topographically complex region that results in large variations in the mesoscale high wind and precipitation features across the region. The goals of this project are to increase the understanding of the three-dimensional structure of these mesoscale meteorology features. This project will leverage observations from the scanning X-band radar installed during the AWARE field campaign in 2016 and the installation of an EWR Radar Systems X-band scanning radar (E700XD) to be deployed during the 2019-20 field season.
Intellectual Merit:
The focus of the science will be on questions investigating the structure and forcing of mesoscale wind and precipitation features in the vicinity of McMurdo Station. In addition to the data from the X-band scanning radars, observations from surface-based automatic weather stations, radiosonde launches from McMurdo Station, the suite of AWARE observations, and archived forecasts from the Antarctic Mesoscale Prediction System will be used to provide verification and additional insights into the structure of these mesoscale features. The science questions to be addressed in this study are:
- What are the signatures of the mesoscale high wind features that are detectable by a scanning X-band, Doppler radar that can be used to aid in operational forecasting and to increase lead time of high wind event warnings for improved safety and logistics in the Ross Island region?
- How does the orientation of the mesoscale high wind events play a role in the determining the severity of the impacts of the high winds at logistically significant locations across the Ross Island region?
- What is the distribution of precipitation across the Ross Island region? Are there local topographic features that result in banding of precipitation across the region?
- What is the accuracy of AMPS in forecasting mesoscale precipitation and wind features across the Ross Island region during the main body season?
Broader Impacts:
The benefits of this project will extend beyond that of addressing the science questions and into improvements and increased data resources for the logistics, operational forecasting and research communities.
- Provide increased understanding and in-depth analysis of the mesoscale wind and precipitation features detectable using radar observations to be transferred to the NIWC forecasters resulting in increased awareness and training.
- With the comparison of the capabilities of the AWARE radar to that of the EWR Radar Systems E700XD the USAP can make an informed decision for the future purchase of a similar or different radar system for long-term deployment and use in forecasting for the region.
- Develop a robust and coordinated data archive of the EWR Radar Systems E700XD during the 2019-20 deployment to be shared and used by future research investigations.
- Provide insight, tools, and an outline for additional studies based on the remote sensing dataset collected during the AWARE project.
Geological records from the Antarctic Ice Sheet (AIS) margin demonstrate that the ice sheet oscillated in response to orbital variations in insolation (i.e., ~400, 100, 41, and 20 kyr), and it appears to be more sensitive to specific frequencies that regulate mean annual insolation (i.e., 41-kyr obliquity), particularly when the ice sheet extends into marine environments and is impacted by ocean circulation. However, the relationship between orbital forcing and the production of Antarctic Bottom Water (AABW) is unconstrained. Thus, a knowledge gap exists in understanding how changing insolation impacts ice marginal and Southern Ocean conditions that directly influence ventilation of the global ocean. We hypothesize that insolation-driven changes directly affected the production and export of AABW to the Southern Ocean from the Pliocene through the Pleistocene. For example, obliquity amplification during the warmer Pliocene may have led to enhanced production and export of dense waters from the shelf due to reduced AIS extent, which, in turn, led to greater AABW outflow. To determine the relationship of AABW production to orbital regime, we plan to reconstruct both from a single, continuous record from the levee of Hillary Canyon, a major conduit of AABW outflow, on the Ross Sea continental rise.
To test our hypothesis, we will analyze sediment from IODP Site U1524 (recovered in 2018 during International Ocean Discovery Program Expedition 374) and focus on three data sets. (1) We will use the occurrence, frequency, and character of mm-scale turbidite beds as a proxy of dense-shelf-water cascading outflow and AABW production. We will estimate the down-slope flux via numerical modeling of turbidity current properties using morphology, grain size, and bed thickness as input parameters. (2) We will use grain-size data, physical properties, XRF core scanning, CT imaging, and hyperspectral imaging to guide lithofacies analysis to infer processes occurring during glacial, deglacial, and interglacial periods. Statistical techniques and optimization methods will be applied to test for astronomical forcing of sedimentary packages in order to provide a cyclostratigraphic framework and interpret the orbital-forcing regime. (3) We will use bulk sedimentary carbon and nitrogen abundance and isotope data to determine how relative contributions of terrigenous and marine organic matter change in response to orbital forcing. We will integrate these data with sedimentological records to deconvolve organic matter production from its deposition or remobilization due to AABW outflow as a function of the oscillating extent of the AIS. These data sets will be integrated into a unified chronostratigraphy to determine the relationship between AABW outflow and orbital-forcing scenarios under the varying climate regimes of the Plio-Pleistocene.
The formation of dense Antarctic Bottom Water (AABW) and its export northward from the Antarctic continent is one of the key components of the global ocean overturning circulation, and plays a critical role in regulating Earth's climate on multi-decadal-to-millennial time scales. Recent studies of the global ocean overturning circulation have increasingly emphasized its three-dimensional structure: AABW is produced in a handful of distinct sites around the Antarctic continent, and there is a pronounced asymmetry in the allocation of AABW transports into the Atlantic, Indian and Pacific basins. The connectivity of AABW between the Antarctic continental shelf and the northern basins is mediated by the Antarctic Circumpolar Current (ACC), a circumpolar eastward flow that also serves as the primary route for inter-basin exchange.
The mapping from different shelf AABW sources to the northern basins dictates the response of the global MOC to localized variability or shifts in the state of the Antarctic shelf, for example due to major glacier calving events or modified inputs of freshwater from the Antarctic ice sheet. At present this mapping is not well constrained, with conflicting conclusions drawn in previous studies: at one extreme the ACC has been suggested to be a ``conduit'' that simply allows each variety of AABW to transit directly northward; at the other extreme, it has been suggested that the ACC ``blends'' all shelf AABW sources together before they reach the northern basins. Such conflicts arise, in part, because little is understood about the physics that determines AABW's pathways across the ACC.
To close this gap in understanding, this collaborative project draws on three complementary analytical tools: process-oriented modeling of AABW export across the ACC, a high-resolution global ocean model, and an observationally-constrained estimate of the global circulation. The PIs will first identify and quantify the pathways of AABW across the ACC by using these tools to propagate passive tracers that identify each of the four major AABW formation sites. They will then use a suite of process model sensitivity experiments to develop a theory for what controls meridional versus inter-basin transport of AABW in the ACC, and transfer this theory to interpret the AABW pathways simulated in the global model. Finally, they will combine the process model, global model and the observationally-constrained circulation product to map the rates at which AABW is transformed into lighter waters, and relate these transformation rates to the diagnosed pathways of AABW across the ACC. This combination of approaches allow the PIs to not only constrain the three-dimensional circulation of AABW from Antarctica to the northern basins, but also provides a mechanistic understanding of the circulation that can be transferred to past or future climates.
Satellite observations show expanding Antarctic sea ice over the last three decades. Increasing Antarctic sea ice seems unexpected when compared to observations of rising global temperatures or shrinking Arctic sea ice. Computer models of global climate also predict Antarctic sea ice to shrink instead of grow. Several hypotheses have been suggested to explain the contradiction between what scientists expect to see based on computer models and physical intuition and the growth that is recorded in observations. This study will examine the hypothesis that sea ice expansion can be explained by sea ice motion, where sea ice moves in such a way as to promote an increase in overall coverage. Researchers will use several different types of computer models, ranging in complexity, to better understand the physical processes of sea ice motion and how the sea ice motion interacts with the larger atmosphere-ocean system. The team will transfer their research to the classroom by hosting a week-long teacher workshop. Teachers will learn how scientists use computer models to test hypotheses and then develop and test tools for use in the classroom. Five middle and high school teachers will participate and become part of the UC San Diego STEM Success Initiative master science teacher network. The project will support a graduate student and a postdoctoral researcher.
Sea ice motion has recently emerged as one of the candidates to explain the Antarctic sea ice expansion but a systematic investigation of how sea ice motion influences sea ice concentration has not been presented to date. Researchers will conduct a process-oriented study of the relationship between sea ice motion and Antarctic sea ice extent using a hierarchy of models. The hierarchy will consist of (i) an idealized single-column model of sea ice evolution, (ii) an idealized latitudinally-varying global model of sea ice and climate, (iii) an atmospheric global climate model (GCM) above a slab ocean that includes sea ice motion, (iv) a comprehensive GCM, and (v) model output from the suite of current comprehensive GCMs. The range of model complexities will help researchers better understand the relationship between sea ice motion and sea ice extent by allowing them to identify important processes that are robust across the model hierarchy.
This project will develop a new ice-penetrating radar system that can simultaneously map glacier geometry (three-dimensional ice-sheet internal architecture and subglacial topography) and glacier flow (vertical velocity of ice) along repeat profiles. Forecasting ice-sheet contribution to sea level requires an estimate for the initial ice-sheet geometry and the parameters that govern ice flow (ice rheology) and slip across bedrock (bed friction). Existing ice-sheet models cannot independently initialize ice rheology and bed friction from conventional observations of surface velocities and glacier geometry. These non-unique solutions for ice-sheet initial state introduce substantial uncertainty into ice-sheet model simulations of past and future ice-sheet behavior.
Spatially-distributed vertical velocities of ice measured by this radar system can be directly compared to simulated vertical velocities produced by glacier models. Thus, this radar technology will allow ice rheology to be constrained independently from bed friction, leading to higher fidelity simulations of past and future ice-sheet behavior and more accurate projections of future sea level.
The new radar system will integrate two existing radars (the multi-channel coherent radio-echo depth sounder and the accumulation radar) developed by the Center for the Remote Sensing of Ice Sheets, but also includes new capabilities. An eight-element very high frequency (VHF; 140-215 MHz) array will have sufficient cross-track aperture to swath map internal layers and the ice-sheet base in three dimensions. A single ultra high frequency (UHF; 600-900 MHz) antenna will have the range and phase resolution to map internal layer displacement with 0.25 mm precision. The VHF array will create 3D mappings of layer geometry that enable measurements of vertical velocities by accounting for spatial offsets between repeat profiles and changing surface conditions. The vertical displacement measurement will then be made by determining the difference in radar phase response recorded by the UHF antenna for radar profiles collected at the same locations at different times. The UHF antenna will be dual-polarized and thus capable of isolating both components of complex internal reflections, which should enable inferences of ice crystal orientation fabric and widespread mapping of ice viscosity. Initial deployment of the radar will occur on the McMurdo Ice Shelf and Thwaites Glacier, Antarctica. The dual-band radar system technology and processing algorithms will be developed with versatile extensible hardware and user-friendly software, so that this system will serve as a prototype for a future community radar system.
The research supported by this grant centers on the evolution of fossil amphibians (temnospondyls) from the Early Triassic, a crucial time interval in the evolution of life on Earth following the end-Permian mass extinction, specifically based on fossil material from Antarctica, a high-latitude paleoenvironment that may have served as a refuge for tetrapods across the extinction event. Previous records of temnospondyls, mostly reported several decades ago, are highly fragmentary, and their original interpretations are considered dubious or demonstrably erroneous by contemporary workers. The Antarctic record of temnospondyls is of great import in understanding the biotic recovery in terrestrial environments for several reasons. Firstly, temnospondyls, like amphibians today, were highly speciose in the Triassic but were also some of the most susceptible to environmental perturbations and instability. Therefore, temnospondyls provide key insights into the paleoenvironmental conditions, either in place of or alongside other lines of data. Secondly, the record of temnospondyls from the Early Triassic is quite rich, but it is also restricted to a few densely sampled regions, such as the Karoo Basin of South Africa. In order to ascertain whether observed patterns such as an unusual abundance of small-bodied taxa or a lack of faunal overlap between different depositional basins (endemism) are real or merely artifactual, study of additional, less sampled regions takes on great import. Recent collection of substantial new temnospondyl material from several horizons in the Triassic exposure of Antarctica provides the requisite data to begin to address these questions. Finally, correlating the Triassic rocks of Antarctica with those of adjacent regions is largely reliant on comparisons of faunal assemblages. In particular, the middle Fremouw Formation, one of the horizons from which new temnospondyl material was collected, remains of uncertain relation and age due to the paucity of described material.
This project will advance our understanding of Antarctic life during the Permian and Triassic. We will apply an interdisciplinary approach to address relationships between environmental change, faunal composition, and biogeographic patterns in the context of the high-latitude strata preserved in the Buckley and Fremouw formations in the Shackleton Glacier region. We will use multiple types of data to assess paleoenvironment, including: 1) paleosol morphology; 2) paleosol geochemistry; 3) pedogenic organic matter; and 4) fossil wood chronology and stable isotopes. The Fremouw Formation of Antarctica preserves the highest paleolatitude tetrapod fauna of the entire Triassic (~70° S) and thus has the potential to shed important light on the evolution of polar life during the early Mesozoic. We will collect new fossils from known localities to understand the relationship between Antarctic and southern African tetrapod faunas. Furthermore, we will refine the stratigraphic, sedimentological, and geochronological framework for these Mesozoic faunas, which will include using U/Pb detrital zircon dating to provide the first dates for these vertebrate assemblages. In the lab, we will examine the biology of Triassic vertebrates from Antarctica by comparing their bone and tusk histology to conspecifics from lower paleolatitudes. In addition, we will test Bergmann’s Rule with six species (viz. Lystrosaurus curvatus, L. maccaigi, L. murrayi, Prolacerta broomi, Procolophon trigoniceps, and Thrinaxodon liorhinus). The Early Triassic presents a unique opportunity to perform such investigations as there is no other geologic interval in which species occurring in Antarctica can be compared to conspecifics across a range of paleolatitudes.
Understanding the genomic changes underlying adaptations to polar environments is critical for
predicting how ecological changes will affect life in these fragile environments. Accomplishing these goals requires looking in detail at genome-scale data across a wide array of organisms in a phylogenetic framework. This study combines multifaceted computational and functional approaches that involves analyzing in the genic evolution of invertebrate organisms, known as the bryozoans or ectoprocts. In addition, the commonality of our results in other taxa will be tested by comparing the results to those produced from the previous and newly proposed workshops. Specific aims of this study include: 1) identifying genes involved in adaptation to Antarctic marine environments using transcriptomic and genomic data from bryozoans to test for positively selected genes in a phylogenetic framework, 2) experimentally testing identified candidate enzymes (especially those involved in calcium signaling, glycolysis, the citric acid cycle, and the cytoskeleton) for evidence of cold adaption, and 3) conducting computational workshops aimed at training scientists in techniques for the identification of genetic adaptations to polar and other disparate environments. The proposed work provides critical insights into the molecular rules of life in rapidly changing Antarctic environments, and provides important information for understanding how Antarctic taxa will respond to future environmental conditions.
This project extended and combined historical and recent ocean data sets to investigate ice-ocean-interactions along the Pacific continental margin of the West Antarctic Ice Sheet. The synthesis focused on the strikingly different environments on and near the cold Ross Sea and warm Amundsen Sea continental shelves, where available measurements reach back to 1911 and 1994, respectively. On the more extensively covered Ross Sea continental shelf, multiple reoccupations of ocean stations and transects since the 1950s were used to extend our knowledge of ocean thermohaline change and variability. The more rugged Amundsen Sea continental shelf contains the earth's fastest melting ice shelves, which Holland et al (2019) show can be linked to decadal-scale variability in the tropical Pacific, and Jacobs et al. (2021) document as being the primary influence on freshening downstream in the Ross Sea. Recent and potential future rates of sea level rise are the primary broad-scale impacts revealed by the observations of ice and ocean changes in these study areas. More regionally, freshening also influences the properties of slope front and coastal currents, and abyssal water mass formation. The overriding question in such work is whether their contributions to global and regional sea levels will continue to increase ~linearly, perhaps allowing greenhouse gas reductions to head off the worst consequences, or accelerate and contribute to major social and economic upheavals. The compiled ocean station profile data has been derived from measurements made from 16 ships operated by 6 countries, from 5 projects using holes through fast and glacier ice, and from 3 studies using drifting floats. We are grateful to the many individuals who have acquired, processed and provided the data, along with their supporting agencies, and welcome corrections and updates to this archive.
Part I: Nontechnical <br/>Earths warming climate has the potential to drive widespread collapse of glaciers and ice sheets across the planet, driving global sea-level rise. Understanding both the rate and magnitude of such changes is essential for predicting future sea-level and how it will impact infrastructure and property. Collapse of the ice sheets of Antarctica has the potential to raise global sea-level by up to 60 meters. However, not all regions of Antarctica are equally suspectable to collapse. One area with potential for collapse is the Wilkes Subglacial Basin in East Antarctica, a region twice the size of California's Central Valley. Geologic evidence indicates that the ice-sheet in this region has retreated significantly in response to past global warming events. While the geologic record clearly indicates ice-sheets in this area are vulnerable, the rate and magnitude of any future retreat will be influenced significantly by geology of the region. Constraining the geologic controls on the stability of the ice-sheets of the Wilkes Subglacial Basin remains challenging since the ice-sheet hides the geology beneath kilometers of ice. As a step in understanding the potential for future ice loss in the Wilkes Subglacial Basin this project will conduct geophysical analysis of existing data to better constrain the geology of the region. These results will constrain new models designed to understand the tectonics that control the behavior of the ice-sheets in the region. These new models will highlight the geological properties that exert the most significant control on the future of the ice-sheets of the Wilkes Subglacial Basin. Such insights are critical to guide future efforts aimed at collecting in-situ observations needed to more fully constrain Antarctica's potential for future sea-level. <br/><br/> Part II: Technical Description <br/>In polar environments, inward-sloping marine basins are susceptible to an effect known as the marine ice-sheet instability (MISI): run-away ice stream drainage caused by warm ocean water eroding the ice shelf from below. The magnitude and time-scale of the ice-sheet response strongly depend on the physical conditions along the ice-bed interface, which are, to a first order, controlled by the tectonic evolution of the basin. Topography, sedimentology, geothermal heat flux, and mantle viscosity all play critical roles in ice-sheet stability. However, in most cases, these solid-Earth parameters for regions susceptible to the MISI are largely unknown. One region with potential susceptibility to MISI is the Wilkes Subglacial Basin of East Antarctica. The project will provide an integrated investigation of the Wilkes Subglacial Basin, combining geophysical analyses with both mantle flow and ice-sheet modeling to understand the stability of the ice sheet in this region, and the associated potential sea level rise. The work will be focused on four primary objectives: (1) to develop an improved tectonic model for the region based on existing seismic observations as well as existing geophysical and geological data; (2) to use the new tectonic model and seismic data to estimate the thermal, density, and viscosity structure of the upper mantle and to develop a heat flow map for the WSB; (3) to simulate mantle flow and to assess paleotopography based on our density and viscosity constraints; and (4) to assess ice-sheet behavior by modeling (a) past ice-sheet stability using our paleotopography estimates and (b) future ice-sheet stability using our heat flow and mantle viscosity estimates. Ultimately, the project will generate improved images of the geophysical structure beneath the WSB that will allow us to assess the geodynamic origin for this region and to assess the influence of geologic parameters on past, current, and future ice-sheet behavior. These efforts will then highlight areas and geophysical properties that should be the focus of future geophysical deployments.
The cold, dry terrestrial environments of Antarctica are inhospitable for insects, and only three midge species make Antarctica home. Of these, Belgica antarctica is the only species found exclusively in Antarctica, and it has been a resident of Antarctica since the continent split from South America ~30 million years ago. Thus, this species is an excellent system to model the biological history of Antarctica throughout its repeated glaciation events and shifts in climate. This insect is also a classic example of extreme adaptation, and much previous work has focused on identifying the genetic and physiological mechanisms that allow this species to survive where no other insect is capable. However, it has been difficult to pinpoint the unique evolutionary adaptations that are required to survive in Antarctica due to a lack of information from closely related Antarctic and sub-Antarctic species. This project will compare adaptations, genome sequences, and population characteristics of four midge species that span an environmental gradient from sub-Antarctic to Antarctic habitats. In addition to B. antarctica, these species include two species that are strictly sub-Antarctic and a third that is native to the sub-Antarctic but has invaded parts of Antarctica. The researchers, comprised of scientists from the US, UK, Chile, and France, will sample insects from across their geographic range and measure their ability to tolerate environmental stressors (i.e., cold and desiccation), quantify molecular responses to stress, and compare the makeup of the genome and patterns of genetic diversity. This research will contribute to a greater understanding of adaptation to extremes, to an understanding of biodiversity on the planet and to understanding and predicting changes accompanying environmental change. The project will train two graduate students and two postdoctoral researchers, and a K-12 educator will be a member of the field team and will assist with fieldwork and facilitate outreach with schools in the US. The project includes partnership activities with several STEM education organizations to deliver educational content to K-12 and secondary students. This is a project that is jointly funded by the National Science Foundation's Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Each Agency funds the proportion of the budget and the investigators associated with its own country. UK participation in this project includes deploying scientists as part of the field team, supporting field and sampling logistics at remote Antarctic sites, and genome sequencing, annotation, and analyses.
This project focuses on the key physiological adaptations and molecular processes that allow a select few insect species to survive in Antarctica. The focal species are all wingless with limited dispersal capacity, suggesting there is also significant potential to locally adapt to variable environmental conditions across the range of these species. The central hypothesis is that similar molecular mechanisms drive both population-level adaptation to local environmental conditions and macroevolutionary changes across species living in different environments. The specific aims of the project are to 1) Characterize conserved and species-specific adaptations to extreme environments through comparative physiology and transcriptomics, 2) Compare the genome sequences of these species to identify genetic signatures of extreme adaption, and 3) Investigate patterns of diversification and local adaptation across each species? range using population genomics. The project establishes an international collaboration of researchers from the US, UK, Chile, and France with shared interests and complementary expertise in the biology, genomics, and conservation of Antarctic arthropods. The Broader Impacts of the project include training students and partnering with the Living Arts and Science Center to design and implement educational content for K-12 students.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Fish that reside in the harsh, subfreezing waters of the Antarctic and Arctic provide fascinating examples of adaptation to extreme environments. Species at both poles have independently evolved ways to deal with constant cold temperature, including the evolution of antifreeze proteins. Under freezing conditions, these compounds attach to ice crystals and prevent their growth. This lowers the tissue freezing point and reduces the chance the animal will be injured or killed. While it might seem that the need for unique adaptations to survive in polar waters would reduce species diversity in these habitats, recent evidence showed higher speciation rates in fishes from polar environments as compared to those found in warmer waters. This is despite the fact cold temperatures slow cellular processes, which had been expected to lower rates of molecular evolution in these species. To determine how rates of speciation and molecular evolution are linked in marine fishes, this project will compare the genomes of multiple polar and non-polar fishes. By doing so, it will (1) clarify how rates of evolution vary in polar environments, (2) identify general trends that shape the adaptive trajectories of polar fishes, and (3) determine how functional differences shape the evolution of novel compounds such as the antifreeze proteins some polar fishes rely upon to survive. In addition to training a new generation of scientists, the project will develop curriculum and outreach activities for elementary and undergraduate science courses. Materials will be delivered in classrooms across the western United States, with a focus on rural schools as part of a network for promoting evolutionary education in rural communities.
To better understand the biology of polar fishes and the evolution of antifreeze proteins (AFPs), this research will compare the evolutionary histories of cold-adapted organisms to those of related non-polar species from both a genotypic and phenotypic context. In doing so, this research will test whether evolutionary rates are slowed in polar environments, perhaps due to constraints on cellular processes. It will also evaluate the effects of positive selection and the relaxation of selection on genes and pathways, both of which appear to be key adaptive strategies involved in the adaptation to polar environments. To address specific mechanisms by which extreme adaptation occurs, researchers will determine how global gradients of temperature and dissolved oxygen shape genome variation and influence adaptive trajectories among multiple species of eelpouts (family Zoarcidae). An in-vitro experimental approach will then be used to test functional hypotheses about the role of copy number variation in AFP evolution, and how and why multiple antifreeze protein isoforms have evolved. By comparing the genomes of multiple polar and non-polar fishes, the project will clarify how rates of evolution vary in polar environments, identify general trends that shape the adaptive trajectories of cold-adapted marine fishes, and determine how functional differences shape the evolution of novel proteins. This project addresses the strategic programmatic aim to provide a better understanding of the genetic underpinnings of organismal adaptations to their current environment and ways in which polar fishes may respond to changing conditions over different evolutionary time scales. The project is jointly funded by the Antarctic Organisms and Ecosystems Program in the Office of Polar Programs of the Geosciences Directorate, and the Molecular Biophysics Program of the Division of Molecular and Cellular Biosciences in the Biological Sciences Directorate.
The Erebus Bay population of Weddell seals in the Ross Sea of Antarctica is the most southerly breeding population of mammal in the world, closely associated with persistent shore-fast ice, and one that has been intensively studied since 1969. The resulting long-term database, which includes data for over 25,000 marked individuals, contains detailed population information that provides an excellent opportunity to study linkages between environmental conditions and demographic processes in the Antarctic. The study population is of special interest as the Ross Sea is one of the most productive areas of the Southern Ocean and one of the most pristine marine environments on the planet. The study provides long-term demographic data for individual seals
The focus of our research is to examine the regional geochemical variations of well-characterized Pliocene-recent basalt samples along a transect from the Phoenix-Antarctic ridge to James Ross Island (through the South Shetland Islands, Bransfield Strait and the Antarctic Peninsula). The goal is to understand 1) the processes responsible for the generation of chemically diverse basalts in close spatial and temporal proximity within the Antarctic Peninsula and 2) the nature (lithology, composition and temperature) of the heterogeneous mantle source beneath the region.
Recent theoretical and experimental work indicates that in a wide range of altitudes and for periods from a few minutes to several hours, a significant part of the wave activity observed in the thermosphere is due to acoustic gravity waves radiated by infragravity waves in the ocean. It is proposed to study this impressive connection between geospheres in Antarctica, at the location where close proximity of the Ross Ice Shelf makes it very special. Infragravity waves are able to excite the fundamental mode and low-order oscillations in the Ross Ice Shelf at its resonance frequencies, with the latter creating standing wave structures throughout the atmosphere. It is likely that this effect was recently detected using lidar observations at McMurdo. This project will study implications of this phenomenon, as well as more general aspects of wave activity in Antarctic geospheres, using data from a unique combination of recently installed instruments: the Dynasonde at Korean Jang Bogo station, the NSF-sponsored network of seismographs and microbarometers on the Ross Ice Shelf, and the IMS-affiliated infrasound station near McMurdo.
The goal of this research is to study atmospheric waves in the thermosphere in Antarctica and to investigate the roles that the Ross Ice Shelf and the Southern Ocean play in generation of the atmospheric waves. Anticipated results are of interest also for general aeronomy and for glaciology. This project will verify the hypothesis that the persistent atmospheric waves in mesosphere and lower thermosphere, which are observed with a lidar instrument at McMurdo, are related to the low-frequency vibration resonances of the Ross Ice Shelf excited by infragravity waves in the ocean. An accurate characterization will be achieved for low-frequency oscillations of the Ross Ice Shelf and the quality factors of its resonances will be assessed. Investigation of a consistency between observed and predicted vertical distributions of the wave intensity is expected to provide insights into where the horizontal momentum carried by AGWs is transferred to the mean motion, i.e., to the large-scale dynamics of the Antarctic thermosphere. A determination of whether accurate measurements of the acoustic resonant frequencies and their variations can provide useful constraints on the neutral temperature profile in the atmosphere will be done. Extensive use of Jang Bogo Dynasonde data in all mentioned tasks will allow further developing Dynasonde techniques.
Worldwide publicity surrounding the calving of an iceberg the size of Delaware in July 2017 from the Larsen C Ice Shelf on the eastern side of the Antarctic Peninsula presents a unique and time-sensitive opportunity for research and education on polar ecosystems in a changing climate. The goal of this project was to convene a workshop, drawing from the large fund of intellectual capital in the US and international Antarctic research communities. The two-day workshop was designed to bring scientists with expertise in Antarctic biological, ecological, and ecosystem sciences to Florida State University to share knowledge, identify important research knowledge gaps, and outline strategic plans for research. Major outcomes from the project were as follows. The international workshop to share and review knowledge concerning the response of Antarctic ecosystems to ice-shelf collapse was held at the Florida State University Coastal and Marine Laboratory (FSUCML) on 18-19 November 2017. Thirty-eight U.S. and international scientists attended the workshop, providing expertise in biological, ecological, geological, biogeographical, and glaciological sciences. Twenty-six additional scientists were either not able to attend or were declined because of having reached maximum capacity of the venue or for not responding to our invitation before the registration deadline. The latest results of ice-shelf research were presented, providing an overview of the current scientific knowledge and understanding of the biological, ecological, geological and cryospheric processes associated with ice-shelf collapse and its ecosystem-level consequences. In addition, several presentations focused on future plans to investigate the impacts of the recent Larsen C collapse. The following presentations were given at the meeting: 1) Cryospheric dynamics and ice-shelf collapse – past and future (M. Truffer, University of Alaska, Fairbanks) 2) The geological history and geological impacts of ice-shelf collapse on the Antarctic Peninsula (Scottt Ishman, Amy Leventer) 3) Pelagic ecosystem responses to ice-shelf collapse (Mattias Cape, Amy Leventer) 4) Benthic ecosystem response to ice-shelf collapse (Craig Smith, Pavica Sršen, Ann Vanreusel) 5) Larsen C and biotic homogenization of the benthos (Richard Aronson, James McClintock, Kathryn Smith, Brittany Steffel) 6) British Antarctic Survey: plans for Larsen C investigations early 2018 and in the future (Huw Griffiths) 7) Feedback on the workshop “Climate change impacts on marine ecosystems: implications for management of living resources and conservation” held 19-22 September 2017, Cambridge, UK (Alex Rogers) 8) Past research activities and plans for Larsen field work by the Alfred Wegener Institute, Germany (Charlotte Havermans, Dieter Piepenburg. One of the salient points emerging from the presentations and ensuing discussions was that, given our poor abilities to predict ecological outcomes of ice-shelf collapses, major cross-disciplinary efforts are needed on a variety of spatial and temporal scales to achieve a broader, predictive understanding of ecosystem consequences of climatic warming and ice-shelf failure. As part of the workshop, the FSUCML Polar Academy Team—Dr. Emily Dolan, Dr. Heidi Geisz, Barbara Shoplock, and Dr. Jeroen Ingels—initiated AntICE: "Antarctic Influences of Climate Change on Ecosystems" (AntICE). They reached out to various groups of school children in the local area (and continue to do so). The AntICE Team have been interacting with these children at Wakulla High School and Wakulla Elementary in Crawfordville; children from the Cornerstone Learning Community, Maclay Middle School, Gilchrist Elementary, and the School of Arts and Sciences in Tallahassee; and the Tallahassee-area homeschooling community to educate them about Antarctic ecosystems and ongoing climate change. The underlying idea was to make the children aware of climatic changes in the Antarctic and their effect on ecosystems so they, in turn, can spread this knowledge to their communities, family and friends – acting as ‘Polar Ambassadors’. We collaborated with the Polar-ICE project, an NSF-funded educational project that established the Polar Literacy Initiative. This program developed the Polar Literacy Principles, which outline essential concepts to improve public understanding of Antarctic and Arctic ecosystems. In the Polar Academy work, we used the Polar Literacy principles, the Polar Academy Team’s own Antarctic scientific efforts, and the experience of the FSU outreach and education program to engage with the children. We focused on the importance of Antarctic organisms and ecosystems, the uniqueness of its biota and the significance of its food webs, as well as how all these are changing and will change further with climate change. Using general presentations, case studies, scientific methodology, individual experiences, interactive discussions and Q&A sessions, the children were guided through the many issues Antarctic ecosystems are facing. Over 300 ''Polar ambassadors'' attended the interactive lectures and afterwards took their creativity to high latitudes by creating welcome letters, displays, dioramas, sculptures, videos and online media to present at the scientific workshop. Over 50 projects were created by the children (Please see supporting files for images). We were also joined by a photographer, Ryan David Reines, to document the event. More information, media and links to online outreach products are available at https://marinelab.fsu.edu/labs/ingels/outreach/polar-academy/
Further concrete products of the workshop: 1) a position-paper focusing on ideas, hypotheses and priorities for investigating the ecological impacts of ice-shelf collapse along the Antarctic Peninsula (Ingels et al., 2018; “The scientific response to Antarctic ice-shelf loss; Nature Climate Change 8, 848-851), and 2) a publication reviewing what is known and unknown about ecological responses to ice-shelf melt and collapse, outlining expected ecological outcomes of ice-shelf disintegration along the Antarctic Peninsula (Ingels et al., 2020; “Antarctic ecosystem responses following ice‐shelf collapse and iceberg calving: Science review and future research”, WIREs Climate Change, e682). The second publication was covered in the The Scientist and by a press-release in Germany, see https://www.altmetric.com/details/91826381. Other products included a poster presentation at the MEASO2018 conference in Hobart, Australia in 2018, and the above-mentioned visits to schools and institutes to talk about the research in invited seminars. We also conducted and active online outreach campaign, with dissemination of our work in various news outlets, blogs, and social media (e.g. reaching >750k total followers on twitter with the publications alone).'
Efforts to improve sea level forecasting on a warming planet have focused on determining the temperature, sea level and extent of polar ice sheets during Earth’s past warm periods. Large uncertainties, however, in reconstructions of past and future sea levels, result from the poorly constrained climate sensitivity of the Antarctic Ice sheet (AIS). This research project aims to develop the use of subglacial precipitates as an archive the Antarctic ice sheet (AIS) past response to climate change. The subglacial precipitates from East Antarctica form in water bodies beneath Antarctic ice and in doing so provide an entirely new and unique measure of how the AIS responds to climate change. In preliminary examination of these precipitates, we identified multiple samples consisting of cyclic opal and calcite that spans hundreds of thousands of years in duration. Our preliminary geochemical characterization of these samples indicates that the observed mineralogic changes result from a cyclic change in subglacial water compositions between isotopically and chemically distinct waters. Opal-forming waters are reduced (Ce* <1 and high Fe/Mn) and exhibit elevated 234U/238U compositions similar to the saline groundwater brines found at the periphery of the AIS. Calcite-forming waters, are rather, oxidized and exhibit δ18O compositions consistent with derivation from the depleted polar plateau (< -50 ‰). 234U-230Th dates permit construction of a robust timeseries describing these mineralogic and compositional changes through time. Comparisons of these time series with other Antarctic climate records (e.g., ice core records) reveal that calcite forming events align with millennial scale changes in local temperature or “Antarctic isotopic maximums”, which represent Southern Hemisphere warm periods during low Atlantic Meridional overturning circulation. Ultimately, this project seeks to develop a comprehensive model as to how changes in the thermohaline cycle induce a glaciologic response which in turn induces a change in the composition of subglacial waters and the mineralogic phase recorded within the precipitate archive.
Antarctica is almost entirely covered by ice, in places over two miles thick. This ice hides a landscape that is less well known than the surface of Mars and represents one of Earth's last unexplored frontiers. Ice-penetrating radar images provide a remote glimpse of this landscape including ice-buried mountains larger than the European Alps and huge fjords twice as deep as the Grand Canyon. The goal of this project is to collect sediment samples derived from these landscapes to determine when and under what conditions these features formed. Specifically, the project seeks to understand the landscape in the context of the history and dynamics of the overlying ice sheet and past mountain-building episodes. This project accomplishes this goal by analyzing sand collected during previous sea-floor drilling expeditions off the coast of Antarctica. This sand was supplied from the continent interior by ancient rivers when it was ice-free over 34 million year ago, and later by glaciers. The project will also study bedrock samples from rare ice-free parts of the Transantarctic Mountains. The primary activity is to apply multiple advanced dating techniques to single mineral grains contained within this sand and rock. Different methods and minerals yield different dates that provide insight into how Antarctica?s landscape has eroded over the many tens of millions of years during which sand was deposited offshore. The dating techniques that are being developed and enhanced for this study have broad application in many branches of geoscience research and industry. The project makes cost-effective use of pre-existing sample collections housed at NSF facilities including the US Polar Rock Repository, the Gulf Coast Core Repository, and the Antarctic Marine Geology Research Facility. The project will contribute to the STEM training of two graduate and two undergraduate students, and includes collaboration among four US universities as well as international collaboration between the US and France. The project also supports outreach in the form of a two-week open workshop giving ten students the opportunity to visit the University of Arizona to conduct STEM-based analytical work and training on Antarctic-based projects. Results from both the project and workshop will be disseminated through presentations at professional meetings, peer-reviewed publications, and through public outreach and media.
The main objective of this project is to reconstruct a chronology of East Antarctic subglacial landscape evolution to understand the tectonic and climatic forcing behind landscape modification, and how it has influenced past ice sheet inception and dynamics. Our approach focuses on acquiring a record of the cooling and erosion history contained in East Antarctic-derived detrital mineral grains and clasts in offshore sediments deposited both before and after the onset of Antarctic glaciation. Samples will be taken from existing drill core and marine sediment core material from offshore Wilkes Land (100°E-160°E) and the Ross Sea. Multiple geo- and thermo-chronometers will be employed to reconstruct source region cooling history including U-Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar. This offshore record will be augmented and tested by applying the same methods to onshore bedrock samples in the Transantarctic Mountains obtained from the US Polar Rock Repository and through fieldwork. The onshore work will additionally address the debated incision history of the large glacial troughs that cut the range, now occupied by glaciers draining the East Antarctic Ice Sheet. This includes collection of samples from several age-elevation transects, apatite 4He/3He thermochronometry, and Pecube thermo-kinematic modeling. Acquiring an extensive geo- and thermo-chronologic database will also provide valuable new information on the poorly known ice-hidden geology and tectonics of subglacial East Antarctica that has implications for improving supercontinent reconstructions and understanding continental break-up.
Antarctic marine ectotherms exhibit universally slow growth, low metabolic rates, and extended development, yet many of their rate processes related to physiology and metabolism are highly thermally sensitive. This suggests that small changes in temperature may result in dramatic changes to energy metabolism, growth, and the rate and duration of development. This project will measure the effects of temperature on metabolism, developmental rate, and the energetic cost of development of four common and ecologically important species of benthic Antarctic marine invertebrates. These effects will be measured over the functional ranges of the organisms and in the context of environmentally relevant seasonal shifts in temperature around McMurdo Sound. Recent data show that seasonal warming of ~1°C near McMurdo Station is accompanied by long-lasting hyperoxic events that impact the benthos in the nearshore boundary layer. This research will provide a more comprehensive understanding of both annual variation in environmental oxygen and temperature across the Sound, and whether this variation drives changes in developmental rate and energetics that are consistent with physiological acclimatization. These data will provide key information about potential impacts of warming Antarctic ectotherms. In addition, this project will support undergraduate and graduate research and partner with large-enrollment undergraduate courses and REU programs at an ANNH and AANAPISI Title III minority-serving institution.
We have completed one of our two scheduled field and data-collecting seasons, but our research was put on hold by COVID and by equipment and sea ice conditions at McMurdo. We have established baseline information on energy utilization by embryos of several species under ambient conditions and early data suggest that metabolism is highly affected by temperature in the range of -2.0 C to 1 C, and less so thereafter.
Ice shelves slow the movement of the grounded ice sheets that feed them. This reduces the rate at which ice sheets loose mass to the oceans and contribute to sea-level rise. But ice shelves can be susceptible to collapse, particularly when surface meltwater accumulates in vulnerable areas. Meltwater lakes can create and enlarge fractures within the ice shelves, thereby triggering or hastening ice-shelf collapse. The drainage of water across the surface of Antarctica and where it accumulates has received little attention. This drainage was assumed to be insignificant, but recent work shows that meltwater can drain for tens of kilometers across ice-shelf surfaces and access areas that would otherwise not accumulate meltwater. Surface meltwater drainage could play a major role in the future stability of ice sheets. This drainage is the focus of this project.
The team will develop and test physics-based mathematical models of water flow and ice-shelf fracture, closely informed by remote sensing observations, to examine (1) how do surface drainage systems respond to inter-annual changes in surface melting, (2) how this drainage is influenced by ice dynamics and (3) whether enlarged drainage systems could deliver meltwater to areas of ice shelves that are vulnerable to water-driven collapse. The project will examine these issues by (1) conducting a remote sensing survey of the structure and temporal evolution of meltwater systems around Antarctica, (2) developing and analyzing mathematical models of water flow across ice shelves, and (3) developing and testing simple models of ice-shelf fracture. An outreach activity will make use of the emerging technology of Augmented Reality to visualize the dynamics of ice sheets in three dimensions to excite the public about glaciology at outreach events around New York City. This approach will be made publicly available for wider use as Augmented Reality continues to grow in popularity.
Three aspects of the project will produce data and code that will be archived in USAP-DC:
1. Mapped ice-shelf drainage system characteristics.
2. Computed continent-wide fields of ice-shelf vulnerability to hydrofracture.
3. An open source augmented reality ice sheet app.
As glaciers creep across the landscape, they can act as earthmovers, plucking up rocks and grinding them into fine sediments. Glaciers have moved across the Antarctic landscape over thousands to millions of years, leaving these ground-up sediments in their wake. This study builds on pilot discoveries by the investigators that revealed remarkably large and variable measurements of surface area in glacially-derived fine-grained sediments found in the McMurdo Dry Valleys (MDV), one of the few landscapes on the Antarctic continent not currently covered by ice. Surface area is key to chemical weathering, the process by which rock is converted to soils as ions are carried away in streams and groundwater. These chemical weathering processes are also one of the primary means by which the Earth system naturally removes carbon dioxide from the atmosphere. Hence, high surface areas observed in sediments implies high "weatherability" which in turn translates to more potential carbon dioxide removed from the atmosphere. Therefore, chemical weathering in high surface area glacial sediments may have significant impacts on Earth's carbon cycle. The researchers will measure the chemical and physical properties of sediments previously collected from the Dry Valleys to understand what factors lead to production of sediment with high-surface area and potential "weather ability" and investigate how sediment produced in these glacial systems could ultimately impact Earth's carbon budget. Results from this research will help scientists (including modelers) refine predictions of the effects of melting glaciers- and attendant exposure of glacial sediment? on atmospheric carbon levels. These results may also contribute to applied research efforts on development of carbon-dioxide removal technologies utilizing principles of rock weathering. In addition to the scientific benefits, this research will involve several students at the undergraduate, graduate, and post-doctoral levels, including science education undergraduates, thus contributing to training of the next-generation STEM workforce.
Physical weathering produces fresh surfaces, greatly enhancing specific surface area (SSA) and reactive surface area (RSA) of primary minerals. Quantifying SSA and RSA of sediments is key to determining dissolution and leaching rates during natural weathering, but few data exist on distribution of sediment SA, particularly in glacial and fluvial systems. Pilot data from glacial stream systems in Taylor Valley and Wright Valley (located in the MDV) exhibit remarkably high and variable values in both SSA and RSA, values that in some cases greatly exceed values from muds in temperate glacial systems. This discovery motivates the current research, which aims to investigate the hypothesis that high and variable SAs of muds within Wright and Taylor Valleys reflect textural and/or compositional inheritance from the differing depositional settings within the MDV, biologic controls, dust additions, and/or pedogenic processes. These hypotheses will be tested by sedimentologically, mineralogically, and geochemically characterizing muds from glacially derived sediment deposited in various environments (cold vs. wet based glaciation; fluvial, lacustrine, dust, and drift deposits) and of varying age (Miocene to Modern) from the MDV and quantifying variation of SA and reactivity. Comparisons with analyzed muds from temperate glacial systems will enable polar-temperate comparisons. Analyses will focus on muds of previously collected sediment from the MDVs. Grain size and SSA will be measured by Laser Analysis and N2 adsorption BET, respectively. After carbonate removal, samples will be re-analyzed for SSA, and muds characterized geochemically. Mineralogy and bulk chemistry will also be assessed on co-occurring sand fractions, and textural attributes documented. SSA-normalized dissolution experiments will be used to compare solutes released from sediments to determine RSAs. Results will be integrated with the various sedimentologic and geochemical analyses to test the posed hypotheses. Ultimately, this research should shed light on how weathering in Antarctic systems contributes to global carbon cycling.
New methodologies for the deployment of coordinated unmanned aerial vehicles will be developed with the aim of attaining whole-colony imagery that can be used to characterize nesting habitats of Adelie penguins at Cape Crozier, on Ross Island, Antarctica. This information will be used to test hypotheses regarding relationships between terrain characteristics, nesting density, and breeding success. This population, potentially the largest in the world and at the southern limit of the species' range, has doubled in size over the past 20 years while most other colonies in the region have remained stable or declined. New information gained from this project will be useful in understanding the potential of climate-driven changes in terrestrial nesting habitats for impacting Adelie penguins in the future. The project will produce, and document, open-source software tools to help automate image processing for automated counting of Adelie penguins. The project will train graduate and undergraduate students and contribute materials to ongoing educational outreach programs based on related penguin science projects. Information gained from this project will contribute towards building robust, cost-effective protocols for monitoring Adelie penguin populations, a key ecosystem indicator identified in the draft Ross Sea Marine Protected Area Research and Monitoring Plan.
Adelie penguins are important indicators of ecosystem function and change in the Southern Ocean. In addition to facing rapid changes in sea ice and other factors in their pelagic environment, their terrestrial nesting habitat is also changing. Understanding the species' response to such changes is critical for assessing its ability to adapt to the changing climate. The objective of this project is to test several hypotheses about the influence of fine-scale nesting habitat, nest density, and breeding success of Adelie penguins in the Ross Sea region. To accomplish this, the project will develop algorithms to improve efficiency and safety of surveys by unmanned aerial systems and develop and disseminate an automated image processing workflow. Images collected during several UAV surveys will be used to estimate the number of nesting adults and chicks produced, as well as estimate nesting density in different parts of two colonies on Ross Island, Antarctica, that differ in size by two orders of magnitude. Imagery will be used to generate high resolution digital surface/elevation models that will allow terrain variables like flood risk and terrain complexity to be derived. Combining the surface model with the nest and chick counts at the two colonies will provide relationships between habitat covariates, nest density, and breeding success. The approaches developed will enable Adelie penguin population sizes and potentially several other indicators in the Ross Sea Marine Protected Area Research and Monitoring Plan to be determined and evaluated. The flight control algorithms developed have the potential to be used for many types of surveys, especially when large areas need to be covered in a short period with extreme weather potential and difficult landing options. Aerial images and video will be used to create useable materials to be included in outreach and educational programs. The automated image processing workflow and classification models will be developed as open source software and will be made freely available for others addressing similar wildlife monitoring challenges.
Polar regions are experiencing some of the most dramatic effects of climate change resulting in large-scale changes in sea ice cover. Despite this, there are relatively few long-term studies on polar species that evaluate the full scope of these effects. Over the last two decades, this team has conducted globally unique demographic studies of Adélie penguins in the Ross Sea, Antarctica, to explore several potential mechanisms for population change. This five-year project will use penguin-borne sensors to evaluate foraging conditions and behavior and environmental conditions on early life stages of Adélie penguins. Results will help to better understand population dynamics and how populations might respond to future environmental change. To promote STEM literacy, education and public outreach efforts will include multiple activities. The PenguinCam and PenguinScience.com website (impacts of >1 million hits per month and use by >300 classrooms/~10,000 students) will be continued. Each field season will also have ‘Live From the Penguins’ Skype calls to classes (~120/season). Classroom-ready activities that are aligned with Next Generation Science Standards will be developed with media products and science journal papers translated to grade 5-8 literacy level. The project will also train early career scientists, postdoctoral scholars, graduate students and post-graduate interns. Finally, in partnership with an Environmental Leadership Program, the team will host 2-year Roger Arliner Young Conservation Fellow, which is a program designed to increase opportunities for recent college graduates of color to learn about, engage with, and enter the environmental conservation sector.
The Ross Sea region of the Southern Ocean is experiencing growing sea ice cover in both extent and duration. These trends contrast those of the well-studied, western Antarctic Peninsula area, where sea ice has been disappearing. Unlike the latter, little is known about how expanding sea ice coverage might affect the regional Antarctic marine ecosystem. This project aims to better understand some of the potential effects of the changing ice conditions on the marine ecosystem using the widely-recognized indicator species - the Adélie Penguin. A four-year effort will build on previous results spanning 19 seasons at Ross Island to explore how successes or failures in each part of the penguin's annual cycle are effected by ice conditions and how these carry over to the next annual recruitment cycle, especially with respect to the penguin's condition upon arrival in the spring. Education and public outreach activities will continually be promoted through the PenguinCam and PenguinScience websites (sites with greater than 1 million hits a month) and "NestCheck" (a site that is logged-on by >300 classrooms annually that allows students to follow penguin families in their breeding efforts). To encourage students in pursuing educational and career pathways in the Science Technology Engineering and Math fields, the project will also provide stories from the field in a Penguin Journal, develop classroom-ready activities aligned with New Generation Science Standards, increase the availability of instructional presentations as powerpoint files and short webisodes. The project will provide additional outreach activities through local, state and national speaking engagements about penguins, Antarctic science and climate change. The annual outreach efforts are aimed at reaching over 15,000 students through the website, 300 teachers through presentations and workshops, and 500 persons in the general public. The project also will train four interns (undergraduate and graduate level), two post-doctoral researchers, and a science writer/photographer. <br/><br/>The project will accomplish three major goals, all of which relate to how Adélie Penguins adapt to, or cope with environmental change. Specifically the project seeks to determine 1) how changing winter sea ice conditions in the Ross Sea region affect penguin migration, behavior and survival and alter the carry-over effects (COEs) to subsequent reproduction; 2) the interplay between extrinsic and intrinsic factors influencing COEs over multiple years of an individual's lifetime; and 3) how local environmental change may affect population change via impacts to nesting habitat, interacting with individual quality and COEs. Retrospective analyses will be conducted using 19 years of colony based data and collect additional information on individually marked, known-age and known-history penguins, from new recruits to possibly senescent individuals. Four years of new information will be gained from efforts based at two colonies (Cape Royds and Crozier), using radio frequency identification tags to automatically collect data on breeding and foraging effort of marked, known-history birds to explore penguin response to resource availability within the colony as well as between colonies (mates, nesting material, habitat availability). Additional geolocation/time-depth recorders will be used to investigate travels and foraging during winter of these birds. The combined efforts will allow an assessment of the effects of penguin behavior/success in one season on its behavior in the next (e.g. how does winter behavior affect arrival time and body condition on subsequent breeding). It is at the individual level that penguins are responding successfully, or not, to ongoing marine habitat change in the Ross Sea region.
Coastal waters surrounding Antarctica represent some of the most biologically rich and most untouched ecosystems on Earth. In large part, this biological richness is concentrated within the numerous openings that riddle the expansive sea ice (these openings are known as polynyas) near the Antarctic continent. These polynyas represent regions of enhanced production known as hot-spots and support the highest animal densities in the Southern Ocean. Many of them are also located adjacent to floating extensions of the vast Antarctic Ice Sheet and receive a substantial amount of meltwater runoff each year during the summer. However, little is known about the specific processes that make these ecosystems so biologically productive. Of the 46 Antarctic coastal polynyas that are presently known, only a handful have been investigated in detail.
This project will develop ecosystem models for the Ross Sea polynya, Amundsen polynya, and Pine Island polynya; three of the most productive Antarctic coastal polynyas. The primary goal is to use these models to better understand the fundamental physical, chemical, and biological interacting processes and differences in these processes that make these systems so biologically productive yet different in some respects (e.g. size and productivity) during the present day settings. Modeling efforts will also be extended to potentially assess how these ecosystems may have functioned in the past and how they might change in the future under different physical and chemical and climatic settings.
The project will advance the education of underrepresented minorities through Stanford?s Summer Undergraduate Research in Geoscience and Engineering (SURGE) Program. SURGE will provide undergraduates the opportunity to gain mentored research experiences at Stanford University in engineering and the geosciences. Old Dominion University also will utilize an outreach programs for local public and private schools as well as an ongoing program supporting the Boy Scout Oceanography merit badge program to create outreach and education impacts.
Polynyas (areas of open water surrounded by sea ice) are disproportionately productive regions of polar ecosystems, yet controls on their high rates of production are not well understood. This project will provide quantitative assessments of the physical and chemical processes that control phytoplankton abundance and productivity within polynyas, how these differ for different polynyas, and how polynyas may change in the future. Of particular interest are the interactions among processes within the polynyas and the summertime melting of nearby ice sheets, including the Thwaites and Pine Island glaciers.
In this proposed study, we will develop a set of comprehensive, high resolution coupled physical-biological models and implement these for three major, but diverse, Antarctic polynyas. These polynyas, the Ross Sea polynya, the Amundsen polynya, and Pine Island polynya, account for >50% of the total Antarctic polynya production.
The research questions to be addressed are: 1) What environmental factors exert the greatest control of primary production in polynyas around Antarctica? 2) What are the controlling physics that leads to the heterogeneity of dissolved iron (dFe) supply to the euphotic zone in polynyas around the Antarctic continental shelf? What effect does this have on local rates of primary production? 3) What are the likely changes in the supply of dFe to the euphotic zone in the next several decades due to climate-induced changes in the physics (winds, sea-ice, ice shelf basal melt, cross-shelf exchange, stratification and vertical mixing) and how will this affect primary productivity around the continent?
The Ross Sea, Amundsen, and Pine Island polynyas are some of the best-sampled polynyas in Antarctica, facilitating model parameterization and validation. Furthermore, these polynyas differ widely in their size, location, sea ice dynamics, relationship to melting ice shelves, and distance from the continental shelf break, making them ideal case studies. For comparison, the western Antarctic Peninsula (wAP), a productive continental shelf where polynyas are a relatively minor contributor to biological production, will also be modeled. Investigating specific processes within different types Antarctic coastal waters will provide a better understand of how these important biological oases function and how they might change under different environmental conditions.
Accurately measuring precipitation in Antarctica is important for purposes such as calculating Antarctica?s mass balance and contribution to global sea level rise, interpreting ice core records, and validating model- and satellite-based precipitation estimates. There is a critical need for reliable, autonomous, long-term measurements of Antarctic precipitation in order to better understand its variability in space in time. Such records over time are essentially absent from the continent, despite their importance. This project will deploy and test instrumentation to measure and record rates of snowfall and blowing snow in Antarctica.
Project goals are based on installation of four low-power, autonomous Antarctic precipitation systems (APS) co-located at automatic weather station (AWS) sites in the Ross Island region of Antarctica. The APSs are designed with an integrated sensor approach to provide multiple types of observations of snow accumulation types at the test sites. The APSs are designed to construct an accurate timeline of snow accumulation, and to distinguish the water equivalent of fallen precipitation from surface blowing (lofted) snow, a prime confounding factor. The standard suite of instruments to be deployed includes: precipitation gauge with double Alter windshield, laser disdrometer, laser snow height sensor, optical precipitation detector, anemometer at gauge height, and a visible /infrared webcam. These instruments have previously been shown to work well in cold regions applications.
This award supports a project intended to discover, through field observations and numerical simulations, how ocean wave-induced vibrations on ice shelves in general, and the Ross Ice Shelf (RIS), in particular, can be used (1) to infer spatial and temporal variability of ice shelf mechanical properties, (2) to infer bulk elastic properties from signal propagation characteristics, and (3) to determine whether the RIS response to infragravity (IG) wave forcing observed distant from the front propagates as stress waves from the front or is "locally" generated by IG wave energy penetrating the RIS cavity. The intellectual merit of the work is that ocean gravity waves are dynamic elements of the global ocean environment, affected by ocean warming and changes in ocean and atmospheric circulation patterns. Their evolution may thus drive changes in ice-shelf stability by both mechanical interactions, and potentially increased basal melting, which in turn feed back on sea level rise. Gravity wave-induced signal propagation across ice shelves depends on ice shelf and sub-shelf water cavity geometry (e.g. structure, thickness, crevasse density and orientation), as well as ice shelf physical properties. Emphasis will be placed on observation and modeling of the RIS response to IG wave forcing at periods from 75 to 300 s. Because IG waves are not appreciably damped by sea ice, seasonal monitoring will give insights into the year-round RIS response to this oceanographic forcing. The 3-year project will involve a 24-month period of continuous data collection spanning two annual cycles on the RIS. RIS ice-front array coverage overlaps with a synergistic Ross Sea Mantle Structure (RSMS) study, giving an expanded array beneficial for IG wave localization. The ice-shelf deployment will consist of sixteen stations equipped with broadband seismometers and barometers. Three seismic stations near the RIS front will provide reference response/forcing functions, and measure the variability of the response across the front. A linear seismic array orthogonal to the front will consist of three stations in-line with three RSMS stations. Passive seismic array monitoring will be used to determine the spatial and temporal distribution of ocean wave-induced signal sources along the front of the RIS and estimate ice shelf structure, with the high-density array used to monitor and localize fracture (icequake) activity. The broader impacts include providing baseline measurements to enable detection of ice-shelf changes over coming decades which will help scientists and policy-makers respond to the socio-environmental challenges of climate change and sea-level rise. A postdoctoral scholar in interdisciplinary Earth science will be involved throughout the course of the research. Students at Cuyamaca Community College, San Diego County, will develop and manage a web site for the project to be used as a teaching tool for earth science and oceanography classes, with development of an associated web site on waves for middle school students.
Understanding and being able to anticipate changes in the glaciological regime of the Ross Ice Shelf (RIS) and West Antarctic Ice Sheet (WAIS) are key to improving sea level rise projections due to ongoing ice mass loss in West Antarctica. The fate of the WAIS is a first-order climate change and global societal issue for this century and beyond that affects coastal communities and coastal infrastructure globally.
Ice shelf--ocean interactions include impacts from tsunami, ocean swell (10-30s period), and very long period ocean waves that impact ice shelves and produce vibrations that induce a variety of seismic signals detected by seismometers buried in the ice shelf surface layer, called firn. To study the wave-induced vibrations in the RIS, an extensive seismic array was deployed from Nov. 2014 to Nov. 2016. This unique seismometer array deployment on an ice shelf made continuous observations of the response of the RIS to ocean wave impacts from ocean swell and very long period waves. An extensive description of the project motivation and background (including photos and videos of the deployment operations), and list of published studies of analyses of the seismic data collected by this project, are available at the project website https://iceshelfvibes.ucsd.edu.
Two types of seismic signals detected by the seismic array are most prevalent: flexural gravity waves (plate waves) and icequakes (signals analogous to those from earthquakes but from fracturing of the ice).
Long period ocean waves flex the ice shelf at the same period as the ocean waves, with wave energy at periods greater than ocean swell more efficient at coupling energy into flexing the ice shelf. Termed flexural gravity waves or plate waves (Chen et al., 2018), their wave-induced vibrations can reach 100’s of km from the ice edge where they are excited, with long period wave energy propagating in the water layer below the shelf coupled with the ice shelf flexure. Flexural gravity waves at very long periods (> 300 s period), such as from tsunami impacts (Bromirski et al., 2017), can readily reach grounding zones and may play a role in long-term grounding zone evolution.
Swell-induced icequake activity was found to be most prevalent at the shelf front during the austral summer (January – March) when seasonal sea ice is absent and the associated damping of swell by sea ice is minimal (Chen et al., 2019).
In addition to the seismic array, a 14 station GPS (global positioning system) array was installed during seismic data retrieval and station servicing operations in October-November 2015. The GPS stations, co-located with seismic stations, extended from the shelf front southward to about 415 km at interior station RS18. Due to logistical constraints associated with battery weight during installation, only one station (at DR10) operated year-round. The GPS data collected give a detailed record of changes in iceflow velocity that are in close agreement with the increasing velocity estimates approaching the shelf front from satellite observations. Importantly, the year-round data at DR10 show an unprecedented seasonal cycle of changes in iceflow velocity, with a speed-up in northward (seaward) ice flow during Jan.-May and then a velocity decrease from June-Sep. (returning to the long-term mean flow velocity). This annual ice flow velocity change cycle has been attributed in part to seasonal changes in ice shelf mass (thinning, reducing buttressing) due to melting at the RIS basal (bottom) surface from intrusion of warmer ocean water (Klein et al., 2020).
This project contributes to the joint initiative launched by the U.S. National Science Foundation (NSF) and the U.K. Natural Environment Research Council (NERC) to substantially improve decadal and longer-term projections of ice loss and sea-level rise originating from Thwaites Glacier in West Antarctica. Thwaites and neighboring glaciers in the Amundsen Sea Embayment are rapidly losing mass in response to recent climate warming and related changes in ocean circulation. Mass loss from the Amundsen Sea Embayment could lead to the eventual collapse of the West Antarctic Ice Sheet, raising the global sea level by up to 2.5 meters (8 feet) in as short as 500 years. The processes driving the loss appear to be warmer ocean circulation and changes in the width and flow speed of the glacier, but a better understanding of these changes is needed to refine predictions of how the glacier will evolve. One highly sensitive process is the transitional flow of glacier ice from land onto the ocean to become a floating ice shelf. This flow of ice from grounded to floating is affected by changes in air temperature and snowfall at the surface; the speed and thickness of ice feeding it from upstream; and the ocean temperature, salinity, bathymetry, and currents that the ice flows into. The project team will gather new measurements of each of these local environmental conditions so that it can better predict how future changes in air, ocean, or the ice will affect the loss of ice to the ocean in this region. <br/> <br/>Current and anticipated near-future mass loss from Thwaites Glacier and nearby Amundsen Sea Embayment region is mainly attributed to reduction in ice-shelf buttressing due to sub-ice-shelf melting by intrusion of relatively warm Circumpolar Deep Water into sub-ice-shelf cavities. Such predictions for mass loss, however, still lack understanding of the dominant processes at and near grounding zones, especially their spatial and temporal variability, as well as atmospheric and oceanic drivers of these processes. This project aims to constrain and compare these processes for the Thwaites and the Dotson Ice Shelves, which are connected through upstream ice dynamics, but influenced by different submarine troughs. The team's specific objectives are to: 1) install atmosphere-ice-ocean multi-sensor remote autonomous stations on the ice shelves for two years to provide sub-daily continuous observations of concurrent oceanic, glaciologic, and atmospheric conditions; 2) measure ocean properties on the continental shelf adjacent to ice-shelf fronts (using seal tagging, glider-based and ship-based surveys, and existing moored and conductivity-temperature-depth-cast data), 3) measure ocean properties into sub-ice-shelf cavities (using autonomous underwater vehicles) to detail ocean transports and heat fluxes; and 4) constrain current ice-shelf and sub-ice-shelf cavity geometry, ice flow, and firn properties for the ice-shelves (using radar, active-source seismic, and gravimetric methods) to better understand the impact of ocean and atmosphere on the ice-sheet change. The team will also engage the public and bring awareness to this rapidly changing component of the cryosphere through a "Live from the Ice" social media campaign in which the public can follow the action and data collection from the perspective of tagged seals and autonomous stations.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
In this project, the researchers processed and analyzed previously acquired seismic data from the POLENET-ANET array (2010-2011) to estimate variations in seismic shear-wave speed beneath the array. This investigation used a passive seismology method call ambient noise tomography, whereby repetitive seismic noise correlation functions were computed from records of Earth's ambient seismic noise field. The main results indicate a shallower Moho beneath Marie Byrd Land compared to previous studies in the region.
The Siple Coast in West Antarctica has undergone significant glacier changes over the last millenium. Several ice streams--rapidly moving streams of ice bordered by slow-moving ice--exist in this region that feeds into the Ross Ice Shelf. A long-term slowdown of Whillans Ice Stream appears to be occurring, and this is affecting the zone between the Whillans and Mercer Ice Streams. However, the consistency of this slowdown and resulting changes to the shear margin between the two ice streams are unknown. Shear zone stability represents a potentially critical control on mass balance of ice sheets, especially in regions of fast ice flow where basal shear stress is minimal. This project is therefore focused on understanding the spatial and temporal change of ice flow kinematics, shear margin structure, and shear margin location between Whillans and Mercer Ice Streams. A collateral benefit of and driver for this as a RAPID project is to test a method for assessing where crevassing will develop in this zone of steep velocity gradients. Such a method may benefit not only near-term field-project planning in the 2018-19 field season, but also planning for future fieldwork and traverses.<br/><br/>The team will use velocity estimates derived from available remote sensing datasets to determine transient velocity patterns and shifts in the shear-zone location over the last 20 years. This velocity time series will be incorporated into a large-scale ice-sheet model to estimate ice-sheet susceptibility to changing boundary conditions over the next century based on likely regional ice-flux scenarios. This approach is an extension of recent work conducted by the team that shows promise for predicting areas of changing high strain rates indicative of an active glacier shear margin. The ultimate objectives are to characterize the flow field of merging ice streams over time and investigate lateral boundary migration. This will provide a better understanding of shear-margin control on ice-shelf and up-glacier stability.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The transition of young from parental care to independence is a critical stage in the life of many animals. Surviving this stage can be especially challenging for polar mammals where the extreme cold requires extra energy to keep warm, rather than using the majority of energy for growth, development and physical activities. Young Weddell seals (Leptonychotes weddellii) have only weeks to develop the capabilities to survive both on top of the sea ice and within the -1.9°C seawater where they can forage for food. The project seeks to better understand how Weddell seal pups rapidly develop (within weeks) the capacity to transition between these two extreme environments (that differ greatly in their abilities to conduct heat) and how they budget their energy during the transition. Though the biology and physiology of adult Weddell seals is well studied, the energetic and physiological strategies of pups during development is still unclear. Understanding factors that may affect survival at critical life history events is essential for better understanding factors that might affect marine mammal populations. Weddell seals are the southernmost breeding mammal and are easily recognizable as quintessential Antarctic seals. Determining potential vulnerabilities at critical life stages to change in the Antarctic environment will facilitate the researchers' ability to not only gain public interest but also communicate how research is revealing ways in which changes are occurring at the poles and how these changes may affect polar ecosystems. By collaborating with the Marine Mammal Center, the project will directly reach the public, through curricular educational materials and public outreach that will impact over 100,000 visitors annually.<br/><br/>To elucidate the physiological strategies that facilitate the survival of Weddell seal pups from birth to independence, the proposed study examines the development of their thermoregulation and diving capability. To achieve this, the project will determine the mechanisms that Weddell seal pups use to maintain a stable, warm body temperature in air and in water and then examine the development of diving capability as the animals prepare for independent foraging. The researchers will take a fully integrative approach- making assessments from proteins to tissues to the whole-animal level- when investigating both these objectives. To assess the development of thermoregulatory capability, researchers will quantify body insulation, resting metabolic rates in air and in water, muscle thermogenesis (shivering), and body surface temperatures in the field. The project will also assess the development of dive capability by quantifying oxygen storage capacities and measuring early dive behavior. To identify possible cellular mechanisms for how Weddell seals navigate this trade-off during development, the program will quantify several key developmental regulators of increased hypoxic capacity (HIF, VEGF and EPO) using qPCR, as well as follow the proteomic changes of adipose and muscle tissue, which will include abundance changes of metabolic, antioxidant, cytoskeletal, and Ca2+-regulating proteins. The study of the physiological development leading up to the transition to independence in pinnipeds will help researchers better predict the effects of climate change on the distribution and abundance of this species and how this will affect other trophic levels. Environmental changes that alter habitat suitability have been shown to decrease population health, specifically because of declines in juvenile survival.
The East Antarctic Ice Sheet holds the largest volume of freshwater on the planet, in total enough to raise sea level by almost two hundred feet. Even minor adjustments in the volume of ice stored have major implications for coastlines and climates around the world. The question motivating this project is how did the ice grow to cover the continent over thirty million years ago when Antarctica changed from a warmer environment to an ice-covered southern continent? The seafloor of Prydz Bay, a major drainage basin of the East Antarctic Ice Sheet (EAIS), has been drilled previously to recover sediments dating from millions of years prior to and across the time when inception of continental ice sheets occurred in Antarctica. The last remnants of plant material found as 'biomarkers' in the ocean sediments record the chemical signatures of rain and snowfall that fed the plants and later the expanding glaciers. Sediment carried by glaciers was also deposited on the seafloor and can be analyzed to discover how glaciers flowed across the landscape. Here, the researchers will identify precipitation changes that result from, and drive, ice sheet growth. This study will gather data and further analyze samples from the seafloor sediment archives of the International Ocean Discovery Program's (IODP) core repositories. Ultimately these findings can help inform temperature-precipitation-ice linkages within climate and ice sheet models. The project will support the training of three female, early career scientists (PhD & MS students, and research technician) and both PIs and the PhD student will continue their engagement with broadening participation efforts (e.g., Women in Science and Engineering Program; local chapters of Society for the advancement of Native Americans and Chicanos in Science and other access programs) to recruit undergraduate student participants from underrepresented minorities at both campuses and from local community colleges. Antarctic earth science education materials will be assisted by professional illustrations to be open access and used in public education and communication efforts to engage local communities in Los Angeles CA and Columbia SC. <br/><br/>The researchers at the University of Southern California and the University of South Carolina will together study the penultimate moment of the early Cenozoic greenhouse climate state: the ~4 million years of global cooling that culminated in the Eocene/Oligocene transition (~34 Ma). Significant gaps remain in the understanding of the conditions that preceded ice expansion on Antarctica. In particular, the supply of raw material for ice sheets (i.e., moisture) and the timing, frequency, and duration of precursor glaciations is poorly constrained. This collaborative proposal combines organic and inorganic proxies to examine how Antarctic hydroclimate changed during the greenhouse to icehouse transition. The central hypothesis is that the hydrological cycle weakened as cooling proceeded. Plant-wax hydrogen and carbon isotopes (hydroclimate proxies) and Hf-Nd isotopes of lithogenous and hydrogenous sediments (mechanical weathering proxies) respond strongly and rapidly to precipitation and glacial advance. This detailed and sensitive combined approach will test whether there were hidden glaciations (and/or warm events) that punctuated the pre-icehouse interval. Studies will be conducted on Prydz Bay marine sediment cores in a depositional area for products of weathering and erosion that were (and are) transported through Lambert Graben from the center of Antarctica. The project will yield proxy information about the presence of plants and the hydroclimate of Antarctica and the timing of glacial advance, and is expected to show drying associated with cooling and ice-sheet growth. The dual approach will untangle climate signals from changes in fluvial versus glacial erosion of plant biomarkers. This proposal is potentially transformative because the combination of organic and inorganic proxies can reveal rapid transitions in aridity and glacial expansion, that may have been missed in slower-response proxies and more distal archives. The research is significant as hydroclimate seems to be a key player in the temperature-cryosphere hysteresis.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Our project is focused on better resolving the three-dimensional Antarctic mantle structure to further understanding of continental tectonics. To accomplish this, we are utilizing a full-waveform tomographic inversion technique that incorporates long-period ambient noise data and which has been shown to more accurately resolve structure than traditional tomographic approaches. The new models have been developed using the Alabama supercomputer facilities in conjunction with software developed at The University of Rhode Island. Our new tomographic results highlight the lithospheric structure beneath the Wilkes and Aurora Subglacial Basins in East Antarctica, where previous rifting episodes and mid-lithospheric discontinuities are being explored. In West Antarctica, the work is elucidating the easternmost extent of the West Antarctic Rift System as well as rifted structure and possible compositional variations within the Weddell Sea. We are also highlighting regions of Antarctica where tomographic resolution is still lacking and where future deployments are needed to improve resolution.
This award supports a project to undertake a systematic examination of the effects of soluble impurities, particularly sulfuric acid, on the creep of polycrystalline ice as function of temperature, strain rate and impurity concentration. The working hypothesis is that soluble impurities will increase the flow rate of polycrystalline ice compared to high-purity ice, that this effect will be temperature dependent and that the impurities by affecting the re-crystallization and grain growth will change the fabric of the ice. Both H2SO4-doped and high-purity poly-crystalline ice will be produced by freezing sheets of ice, breaking them up, sieving the ice particles and then sintering them in a mold into fine-grained cylindrical specimens with at least ten grains across their diameter. The resulting microstructures (dislocation structure, grain size and shape, grain boundary character and micro-structural location of the acid) will be characterized using a variety of techniques including: optical microscopy, scanning electron microscopy, including secondary electron imaging, electron backscattered patterns, energy dispersive X-ray spectroscopy, electron channeling contrast imaging, and X-ray topography. The creep of both the H2SO4-doped and the high-purity polycrystalline ice will be undertaken at a range of temperatures and stresses. The ice?s response to the creep deformation (grain boundary sliding, dislocation motion, re-crystallization, grain boundary migration, impurity redistribution) will be studied using a combination of methods. The creep behavior will be modeled and related to the microstructure. Of particular interest is how impurities affect the activation energy for creep. The intellectual merit of the work is that it will lead to a better understanding of glacier ice and will enable glaciologists to model the influence of impurities on the flow and fabric development in polycrystalline ice. The broader impacts of the project include the knowledge that will be gained of the effects of impurities on the flow of ice which will allow paleoclimatologists to better interpret ice core data and will allow scientists developing predictive models to better address the flow of ice sheets under various climate change scenarios. The project will also lead to the education and training of a Ph.D. student, several undergraduates and some high school students. Results from the research will be published in refereed journals. Several undergraduates, typically two per year, will also perform the work. Dartmouth aggressively courts minority students at all degree levels, and we will seek women or minority group undergraduates for this project. The undergraduates will be supported by Dartmouth?s nationally-honored Women In Science Project or by REU funding. The undergraduates? research will integrate closely with the Ph.D. student?s studies. Hanover High School students will also be involved in the project and develop an educational kit to introduce students to the properties of ice. Results from the research will be published in refereed journals and presented at conferences.
Accurate parameterizations of the air-sea fluxes of CO2 into the Southern Ocean, in particular at high wind velocity, are needed to better assess how projections of global climate warming in a windier world could affect the ocean carbon uptake, and alter the ocean heat budget at high latitudes. <br/><br/>Air-sea fluxes of momentum, sensible and latent heat (water vapor) and carbon dioxide (CO2) are to be measured continuously underway on cruises using micrometeorological eddy covariance techniques adapted to ship-board use. The measured gas transfer velocity (K) is then to be related to other parameters known to affect air-sea-fluxes.<br/><br/>A stated goal of this work is the collection of a set of direct air-sea flux measurements at high wind speeds, conditions where parameterization of the relationship of gas exchange to wind-speed remains contentious. The studies will be carried out at sites in the Southern Ocean using the USAP RV Nathaniel B Palmer as measurment platform. Co-located pCO2 data, to be used in the overall analysis and enabling internal consistency checks, are being collected from existing underway systems aboard the USAP research vessel under other NSF awards.
Glacier ice loss from Antarctica has the potential to lead to a significant rise in global sea level. One line of evidence for accelerated glacier ice loss has been an increase in the rate at which the land has been rising across the Antarctic Peninsula as measured by GPS receivers. However, GPS observations of uplift are limited to the last two decades. One goal of this study is to determine how these newly observed rates of uplift compare to average rates of uplift across the Antarctic Peninsula over a longer time interval. Researchers reconstructed past sea levels using the age and elevation of ancient beaches now stranded above sea level on the low-lying coastal hills of the Antarctica Peninsula and determined the rate of uplift over the last 5,000 years. The researchers analyzed the structure of the beaches using ground-penetrating radar and the characteristics of beach sediments to understand how sea-level rise and past climate changes are recorded in beach deposits. We found that unlike most views of how sea level changed across Antarctica over the last 5,000 years, its history is complex with periods of increasing rates of sea-level fall as well as short periods of potential sea-level rise. We attribute these oscillations in the nature of sea-level change across the Antarctic Peninsula to changes in the ice sheet over the last 5,000 years. These changes in sea level also suggest our understanding of the Earth structure beneath the Antarctic Peninsula need to be revised. The beach deposits themselves also record periods of climate change as reflected in the size and shape of their cobbles. This project has lead to the training of five graduate students, three undergraduate students, and outreach talks to k-12 schools in three communities.
General:
Scientists established more than 30 years ago that the climate-related variability of carbon dioxide levels in the atmosphere over Earth’s ice-age cycles was regulated by the ocean. Hypotheses to explain how the ocean that regulates atmospheric carbon dioxide have long been debated, but they have proven to be difficult to test. This project was designed test one leading hypothesis, specifically that the ocean experienced greater density stratification during the ice ages. That is, with greater stratification during the ice ages and the slower replacement of deep water by cold dense water formed near the poles, the deep ocean would have held more carbon dioxide, which is produced by biological respiration of the organic carbon that constantly rains to the abyss in the form of dead organisms and organic debris that sink from the sunlit surface ocean. To test this hypothesis, the degree of ocean stratification during the last ice age and the rate of deep-water replacement was to be constrained by comparing the radiocarbon ages of organisms that grew in the surface ocean and at the sea floor within a critical region around Antarctica, where most of the replacement of deep waters occurs. Completing this work was expected to contribute toward improved models of future climate change. Climate scientists rely on models to estimate the amount of fossil fuel carbon dioxide that will be absorbed by the ocean in the future. Currently the ocean absorbs about 25% of the carbon dioxide produced by burning fossil fuels. Most of this carbon is absorbed in the Southern Ocean (the region around Antarctica). How this will change in the future is poorly known. Models have difficulty representing physical conditions in the Southern Ocean accurately, thereby adding substantial uncertainty to projections of future ocean uptake of carbon dioxide. Results of the proposed study will provide a benchmark to test the ability of models to simulate ocean processes under climate conditions distinctly different from those that occur today, ultimately leading to improvement of the models and to more reliable projections of future absorption of carbon dioxide by the ocean.
Technical:
The project added a research component to an existing scientific expedition to the Southern Ocean, in the region between the Ross Sea and New Zealand, that collected sediment cores at locations down the northern flank of the Pacific-Antarctic Ridge at approximately 170°W. The goal was to collect sediments at each location deposited since early in the peak of the last ice age. This region is unusual in the Southern Ocean in that sediments deposited during the last ice age contain foraminifera, tiny organisms with calcium carbonate shells, in much greater abundance than in other regions of the Southern Ocean. Foraminifera are widely used as an archive of several geochemical tracers of past ocean conditions. We proposed to compare the radiocarbon age of foraminifera that inhabited the surface ocean with the age of contemporary specimens that grew on the seabed. The difference in age between surface and deep-swelling organisms would have been used to discriminate between two proposed mechanisms of deep water renewal during the ice age: formation in coastal polynyas around the edge of Antarctica, much as occurs today, versus formation by open-ocean convection in deep-water regions far from the continent. If the latter mechanism prevails, then it was expected that surface and deep-dwelling foraminifera would exhibit similar radiocarbon ages. In the case of dominance of deep-water formation in coastal polynyas, one expects to find very different radiocarbon ages in the two populations of foraminifera. In the extreme case of greater ocean stratification during the last ice age, one even expects the surface dwellers to appear to be older than contemporary bottom dwellers because the targeted core sites lie directly under the region where the oldest deep waters outcrop at the surface following their long circuitous transit through the deep ocean. The primary objective of the proposed work was to reconstruct the water mass age structure of the Southern Ocean during the last ice age, which, in turn, is a primary factor that controls the amount of carbon dioxide stored in the deep sea. In addition, the presence of foraminifera in the cores to be recovered provides a valuable resource for many other paleoceanographic applications, such as: 1) the application of nitrogen isotopes to constrain the level of nutrient utilization in the Southern Ocean and, thus, the efficiency of the ocean’s biological pump, 2) the application of neodymium isotopes to constrain the transport history of deep water masses, 3) the application of boron isotopes and boron/calcium ratios to constrain the pH and inorganic carbon system parameters of ice-age seawater, and 4) the exploitation of metal/calcium ratios in foraminifera to reconstruct the temperature (Mg/Ca) and nutrient content (Cd/Ca) of deep waters during the last ice age at a location near their source near Antarctica.
Unfortunately, the cores were shipped to the core repository in a horizontal orientation and there was sufficient distortion of the sediment that the radiocarbon ages of benthic foraminifera were uninterpretable. Therefore, we report only the radiocarbon dates for planktonic foraminifera as well as the total counts of elemental relative abundance from X-ray Fluorescence analysis of the cores. In addition, we used the expedition as an opportunity to collect water samples from which dissolved concentrations of long-lived isotope of thorium and protactinium were determined. Results from those analyses showed that lateral transport by isopycnal mixing dominates the supply of Pa to the Southern Ocean. We have also developed a new algorithm to correct for supply of Th by isopycnal mixing and thereby derive estimates of dust flux to the Southern Ocean.
In Antarctica, millions of years of freezing have led to the development of hundreds of meters of thick permafrost (i.e., frozen ground). Recent research demonstrated that this slow freezing has trapped and concentrated water into local and regional briny aquifers, many times more salty than seawater. Because salt depresses the freezing point of water, these saline brines are able to persist as liquid water at temperatures well below the normal freezing point of freshwater. Such unusual groundwater systems may support microbial life, supply nutrients to coastal ocean and ice-covered lakes, and influence motion of glaciers. These briny aquifers also represent potential terrestrial analogs for deep life habitats on other planets, such as Mars, and provide a testing ground for the search for extraterrestrial water. Whereas much effort has been invested in understanding the physics, chemistry, and biology of surface and near-surface waters in cold polar regions, it has been comparably difficult to investigate deep subsurface aquifers in such settings. Airborne ElectroMagnetics (AEM) subsurface imaging provides an efficient way for mapping salty groundwater. An international collaboration with the University of Aarhus in Denmark will enable knowledge and skill transfer in AEM techniques that will enhance US polar research capabilities and provide US undergraduates and graduate students with unique training experiences. This project will survey over 1000 km2 of ocean and land near McMurdo Station in Antarctica, and will reveal if cold polar deserts hide a subsurface pool of liquid water. This will have significant implications for understanding cold polar glaciers, ice-covered lakes, frozen ground, and polar microbiology as well as for predictions of their response to future change. Improvements in permafrost mapping techniques and understanding of permafrost and of underlying groundwaters will benefit human use of high polar regions in the Antarctic and the Arctic.<br/><br/>The project will provide the first integrative system-scale overview of subsurface water distribution and hydrological connectivity in a partly ice-free coastal region of Antarctica, the McMurdo Dry Valleys. Liquid water is relatively scarce in this environment but plays an outsized role by influencing, and integrating, biological, biogeochemical, glaciological, and geological processes. Whereas surface hydrology and its role in ecosystem processes has been thoroughly studied over the last several decades, it has been difficult to map out and characterize subsurface water reservoirs and to understand their interactions with regional lakes, glaciers, and coastal waters. The proposed project builds on the "proof-of-concept" use of AEM technology in 2011. Improvements in sensor and data processing capabilities will result in about double the depth of penetration of the subsurface during the new data collection when compared to the 2011 proof-of-concept survey, which reached depths of 300-400m. The first field season will focus on collecting deep soundings with a ground-based system in key locations where: (i) independent constraints on subsurface structure exist from past drilling projects, and (ii) the 2011 resistivity dataset indicates the need for deeper penetration and high signal-to-noise ratios achievable only with a ground-based system. The regional airborne survey will take place during the second field season and will yield subsurface electrical resistivity data from across several valleys of different sizes and different ice cover fractions.
The Antarctic subglacial environment remains one of the least explored regions on Earth. This project will examine the physical and biological characteristics of Subglacial Lake Mercer, a lake that lies 1200m beneath the West Antarctic Ice Sheet. This study will address key questions relating to the stability of the ice sheet, the subglacial hydrological system, and the deep-cold subglacial biosphere. The education and outreach component aims to widely disseminate results to the scientific community and to the general public through short films, a blog, and a website.<br/><br/>Subglacial Lake Mercer is one of the larger hydrologically active lakes in the southern basin of the Whillans Ice Plain, West Antarctica. It receives about 25 percent of its water from East Antarctica with the remainder originating from West Antarctica, is influenced by drain/fill cycles in a lake immediately upstream (Subglacial Lake Conway), and lies about 100 km upstream of the present grounding line of the Ross Ice Shelf. This site will yield information on the history of the Whillans and Mercer Ice Streams, and on grounding line migration. The integrated study will include direct sampling of basal ice, water, and sediment from the lake in concert with surface geophysical surveys over a three-year period to define the hydrological connectivity among lakes on the Whillans Ice Plain and their flow paths to the sea. The geophysical surveys will furnish information on subglacial hydrology, aid the site selection for hot-water drilling, and provide spatial context for interpreting findings. The hot-water-drilled boreholes will be used to collect basal ice samples, provide access for direct measurement of subglacial physical, chemical, and biological conditions in the water column and sediments, and to explore the subglacial water cavities using a remotely operated vehicle equipped with sensors, cameras, and sampling equipment. Data collected from this study will address the overarching hypothesis \"Contemporary biodiversity and carbon cycling in hydrologically-active subglacial environments associated with the Mercer and Whillans ice streams are regulated by the mineralization and cycling of relict marine organic matter and through interactions among ice, rock, water, and sediments\". The project will be undertaken by a collaborative team of scientists, with expertise in microbiology, biogeochemistry, hydrology, geophysics, glaciology, marine geology, paleoceanography, and science communication.
The ocean tide is a large component of total variability of ocean surface height and currents in the seas surrounding Antarctica, including under the floating ice shelves. Maximum tidal height range exceeds 7 m (near the grounding line of Rutford Ice Stream) and maximum tidal currents exceed 1 m/s (near the shelf break in the northwest Ross Sea). Tides contribute to several important climate and ecosystems processes including: ocean mixing, production of dense bottom water, flow of warm Circumpolar Deep Water onto the continental shelves, melting at the bases of ice shelves, fracturing of the ice sheet near a glacier or ice stream’s grounding line, production and decay of sea ice, and sediment resuspension. Tide heights and, in particular, currents can change as the ocean background state changes, and as the geometry of the coastal margins of the Antarctic Ice Sheet varies through ice shelf thickness changes and ice-front and grounding-line advances or retreats. For satellite-based studies of ocean surface height and ice shelf thickness changes, tide heights are a source of substantial noise that must be removed. Similarly, tidal currents can also be a substantial noise signal when trying to estimate mean ocean currents from short-term measurements such as from acoustic Doppler current profilers mounted on ships and CTD rosettes. Therefore, tide models play critical roles in understanding current and future ocean and ice states, and as a method for removing tides in various measurements. A paper in Reviews of Geophysics (Padman, Siegfried and Fricker, 2018, see list of project-related publications below) provides a detailed review of tides and tidal processes around Antarctica.
This project provides a gateway to tide models and a database of tide height coefficients at the Antarctic Data Center, and links to toolboxes to work with these models and data.
Overview: In order to close the global overturning circulation, high-density deep- and bottom waters produced at high latitudes must be made less dense and upwell to shallower depths. Available observations from the subtropical South Atlantic indicate that the bulk of the mixing in the deep ocean there takes place over the topographically rough Mid-Atlantic Ridge, in particular in the quasi-regularly spaced "fracture zone canyons" corrugating the ridge flanks. There, dense water is advected toward the ridge crest (i.e. upwelled) by persistent along-valley currents that flow down the unidirectional density gradients, which are maintained by strong turbulence (diapycnal mixing). Most of the data on which these inferences are based were collected during the Brazil Basin Tracer Release Experiment (BBTRE) along a single ridge-flank canyon in the western South Atlantic near 22S where previous analyses have shown that both tidal mixing and overflow processes are important. Therefore, it is likely that both processes must be considered in order to understand and parameterize the effects of turbulence and mixing in the canyons corrugating the flanks of all slow-spreading ridges, which make up large fractions of the sea floor, in particular in the Atlantic, Indian and Southern Oceans. The primary aim of this follow-on project is to improve our understanding of the dynamics over the corrugated flanks of slow-spreading mid-ocean ridges. Due to the coarse sampling resolution and choice of station locations it is not possible to answer important questions, such as the relative importance of tidal and sill mixing, from the BBTRE data. Therefore, high-resolution surveys of hydrography, three-dimensional flow, turbulence and mixing will be carried out in two neighboring canyons and over the intervening topographic spur in the BBTRE region to determine the relative contributions of tidal and sill-related mixing. Furthermore, profiling moorings deployed on two nearby sill regions will be used to derive time series of spatially integrated mixing related buoyancy fluxes and to investigate the strong but unexplained sub-inertial variability of the along-canyon flow recorded previously. Additionally, three small moorings will be deployed in saddles between the two canyons to investigate inter-canyon exchange. The data analysis will include available data from previous experiments, including a set of tracer profiles that has not been analyzed before. Intellectual Merit: The corrugated flanks of slow-spreading ridges cover large areas of the sea floor of several major ocean basins. Therefore, understanding the dynamics in the ~100 km of ridge-flank canyons and its effects on the buoyancy and upwelling budget of the abyssal ocean is of global significance. In addition to determining the relative importance of tidal mixing and cross-sill flows in two canyons, the temporal variability of turbulence and mixing from tidal to yearly time scales will be investigated to gain insights into the forcing of the along-canyon flows, the exchange between neighboring canyons, and the eventual fate of the canyon waters. Broader Impacts: It is anticipated that insights gained during this project will improve our understanding of abyssal mixing in many different regions with similar bottom topography and provide the basis for better parameterizations of the effects of turbulence and mixing in large-scale circulation and climate models that cannot resolve these small-scale processes. As part of the project, a graduate student and a post-doctoral researcher will be trained in all aspects of observational physical oceanography, from data acquisition to interpretation.
Atmospheric oxygen rose suddenly approximately 2.4 billion years ago after Cyanobacteria evolved the ability to produce oxygen through photosynthesis (oxygenic photosynthesis). This change permanently altered the future of life on Earth, yet little is known about the evolutionary processes leading to it. The Melainabacteria were first discovered in 2013 and are closely related non-photosynthetic relatives of the first group of organisms capable of oxygenic photosynthesis. This project will utilize existing data on metagenomes from microbial mats in Lake Vanda, an ice-covered lake in Antarctica where many sequences of Melainabacteria have been previously identified.
From this genetic information, we identified a new cyanobacterium, named Aurora vandensis, that is sister to all other Cyanobacteria, providing evolutionary insights. In addition, we assessed the metabolic capabilities of the Melainabacteria with good genomic coverage to identify their potential ecological roles. None contain photosynthetic genes, and we are evaluating the evolutionary relationships among the Cyanobacteria and Melainabacteria, particularly with respect to metabolic genes that will allow an advancement in understanding of the evolutionary path that lead to oxygenic photosynthesis on Earth.
The project will focus on extracting evolutionary information from the genomic data of Melainabacteria and Sericytochromatia, recently-described groups closely related to but basal to the Cyanobacteria. The characterization of novel members of these groups in samples from Lake Vanda, Antarctica, provide insights into the path and processes involved in the evolution of oxygenic photosynthesis. The research identified a novel cyanobacterial genus that is sister to all other Cyanobacteria, is most closely related to Gloeobacter, and shares evolutionary differences with that genus. Results also show that characterized Melainabacteria lack photosynthesis genes, but their respiration genes provide insight into evolutionary relationships among Melainabacteria and Cyanobacteria. Results provide unexpected constraints. The project focuses on 12 metagenomes, from which Melainabacteria and novel Cyanobacteria bins are annotated and preliminary metabolic pathways will be constructed. The project utilizes full-length sequences of marker genes from across the bacterial domain with a particular focus on taxa that are oxygenic or anoxygenic phototrophs and use the marker genes, to build a rooted "backbone" tree. Incomplete or short sequences from the metagenomes are added to the tree using the Evolutionary Placement Algorithm. The researchers built a corresponding phylogenetic tree using a Bayesian framework and compare their topologies. By doing so, the project aims to improve the understanding of the evolution of oxygenic photosynthesis, which caused the most significant change in Earth's surface chemistry. Specifically, we document a novel and basal cyanobacterium, significantly broader metabolic diversity within the Melainabacteria than has been previously identified, gain significant insights into their metabolic evolution, their evolutionary relationships with the Cyanobacteria, and the evolutionary steps leading to the origin of oxygenic photosynthesis. This research is constraining key evolutionary processes in the origin of oxygenic photosynthesis. It provides the foundation for future studies by indicating where a genomic record of the evolution of oxygenic photosynthesis may be preserved. Results will are being shared with middle school children through the development of scientific lesson plans in collaboration with teachers.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The waters of the Ross Sea continental shelf are among the most productive in the Southern Ocean, and may comprise a significant regional oceanic sink for atmospheric carbon dioxide. In this region, primary production can be limited by the supply of dissolved iron to surface waters during the growing season. Water-column observations, sampling and measurements are to be carried out in the late autumn-early winter time frame on the Ross Sea continental shelf and coastal polynyas (Terra Nova Bay and Ross Ice Shelf polynyas), in order to better understand what drives the biogeochemical redistribution of micronutrient iron species during the onset of convective mixing and sea-ice formation at this time of year, thereby setting conditions for primary production during the following spring. The spectacular field setting and remote, hostile conditions that accompany the proposed field study present exciting possibilities for STEM education and training. At the K-12 level, the project seeks to support the development of educational outreach materials targeting elementary and middle school students, pre-service science teachers, and in-service science teachers.
The western Antarctic Peninsula has become a model for understanding cold water communities and how they may be changing in Antarctica and elsewhere. Brown macroalgae (seaweeds) form extensive undersea forests in the northern portion of this region where they play a key role in providing both physical structure and a food (carbon) source for shallow water communities. Yet between Anvers Island (64 degrees S latitude) and Adelaide Island (67 S latitude) these macroalgae become markedly less abundant and diverse. This is probably because the habitat to the south is covered by more sea ice for a longer period, and the sea ice reduces the amount of light that reaches the algae. The reduced macroalgal cover undoubtedly impacts other organisms in the food web, but the ways in which it alters sea-floor community processes and organization is unknown. This project will quantitatively document the macroalgal communities at multiple sites between Anvers and Adelaide Islands using a combination of SCUBA diving, video surveys, and algal collections. Sea ice cover, light levels, and other environmental parameters on community structure will be modelled to determine which factors have the largest influence. Impacts on community structure, food webs, and carbon flow will be assessed through a mixture of SCUBA diving and video surveys. Broader impacts include the training of graduate students and a postdoctoral researcher, as well as numerous informal public education activities including lectures, presentations to K-12 groups, and a variety of social media-based outreach.<br/><br/>Macroalgal communities are more abundance and diverse to the north along the Western Antarctic Peninsula, perhaps due to the greater light availability that is associated with shorter period of sea-ice cover. This project will determine the causes and community level consequence of this variation in algal community structure. First, satellite data on sea ice extent and water turbidity will be used to select study sites between 64 S and 69 S where the extent of annual sea ice cover is the primary factor influencing subsurface light levels. Then, variations in macroalgal cover across these study sites will be determined by video line-transect surveys conducted by SCUBA divers. The health, growth, and physiological status of species found at the different sites will be determined by quadrat sampling. The relative importance of macroalgal-derived carbon to the common invertebrate consumers in the foodweb will be assessed with stable isotope and fatty acid biomarker techniques. This will reveal how variation in macroalgal abundance and species composition across the sea ice cover gradient impacts sea floor community composition and carbon flow throughout the food web. In combination, this work will facilitate predictions of how the ongoing reductions in extent and duration of sea ice cover that is occurring in the region as a result of global climate change will impact the structure of nearshore benthic communities.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The geological structure and history of Antarctica remains poorly understood because much of the continental crust is covered by ice. Here, the PIs will analyze over 15 years of seismic data recorded by numerous projects in Antarctica to develop seismic structural models of the continent. The seismic velocity models will reveal features including crustal thinning due to rifting in West Antarctica, the structures associated with mountain building, and the boundaries between different tectonic blocks. The models will be compared to continents that are better understood geologically to constrain the tectonic evolution of Antarctica. In addition, the work will provide better insight into how the solid earth interacts with and influences the development of the ice sheet. Surface heat flow will be mapped and used to identify regions in Antarctica with potential melting at the base of the ice sheet. This melt can lead to reduced friction and lower resistance to ice sheet movement. The models will help to determine whether the earth response to ice mass changes occurs over decades, hundreds, or thousands of years. Estimates of mantle viscosity calculated from the seismic data will be used to better understand the pattern and timescales of the response of the solid earth to changes in ice mass in various parts of Antarctica.<br/><br/>The study will advance our knowledge of the structure of Antarctica by constructing two new seismic models and a thermal model using different but complementary methodologies. Because of the limitations of different seismic analysis methods, efforts will be divided between a model seeking the highest possible resolution within the upper 200 km depth in the well instrumented region (Bayesian Monte-Carlo joint inversion), and another model determining the structure of the entire continent and surrounding oceans extending through the mantle transition zone (adjoint full waveform inversion). The Monte-Carlo inversion will jointly invert Rayleigh wave group and phase velocities from earthquakes and ambient noise correlation along with P-wave receiver functions and Rayleigh H/V ratios. The inversion will be done in a Bayesian framework that provides uncertainty estimates for the structural model. Azimuthal anisotropy will be determined from Rayleigh wave velocities, providing constraints on mantle fabric and flow patterns. The seismic data will also be inverted for temperature structure, providing estimates of lithospheric thickness and surface heat flow. The larger-scale model will cover the entire continent as well as the surrounding oceans, and will be constructed using an adjoint inversion of phase differences between three component seismograms and synthetic seismograms calculated in a 3D earth model using the spectral element method. This model will fit the entire waveforms, including body waves and both fundamental and higher mode surface waves. Higher resolution results will be obtained by using double-difference methods and by incorporating Green's functions from ambient noise cross-correlation, and solving for both radial and azimuthal anisotropy.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Abstract (non-technical)<br/>Sea level rise is a problem of global importance and it is increasingly affecting the tens of millions of Americans living along coastlines. The melting of glaciers in mountain areas worldwide in response to global warming is a major cause of sea level rise and increases in nuisance coastal flooding. However, the world's largest land-based ice sheets are situated in the Polar Regions and their response under continued warming is very difficult to predict. One reason for this uncertainty is a lack of observations of ice behavior and melt under conditions of warming, as it is a relatively new global climate state lasting only a few generations so far. Researchers will investigate ice growth on Antarctica under past warm conditions using geological archives embedded in the layers of sand and mud under the sea floor near Antarctica. By peeling back at the layers beneath the seafloor investigators can read the history book of past events affecting the ice sheet. The Antarctic continent on the South Pole, carries the largest ice mass in the world. The investigator's findings will substantially improve scientists understanding of the response of ice sheets to global warming and its effect on sea level rise.<br/><br/><br/>Abstract (technical)<br/>The melt of land based ice is raising global sea levels with at present only minor contributions from polar ice sheets. However, the future role of polar ice sheets in climate change is one of the most critical uncertainties in predictions of sea level rise around the globe. The respective roles of oceanic and atmospheric greenhouse forcing on ice sheets are poorly addressed with recent measurements of polar climatology, because of the extreme rise in greenhouse forcing the earth is experiencing at this time. Data on the evolution of the West Antarctic ice sheet is particularly sparse. To address the data gap, researchers will reconstruct the timing and spatial distribution of Antarctic ice growth through the last greenhouse to icehouse climate transition around 37 to 33 Ma. They will collect sedimentological and geochemical data on core samples from a high-latitude paleoarchive to trace the shutdown of the chemical weathering system, the onset of glacial erosion, ice rafting, and sea ice development, as East and West Antarctic ice sheets coalesced in the Weddell Sea sector. Their findings will lead to profound increases in the understanding of the role of greenhouse forcing in ice sheet development and its effect on the global climate system.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This award, provided by the Office of Polar Programs under the Life in Extreme Environments (LExEn) Program, supports a geophysical study of Lake Vostok, a large lake beneath the East Antarctic Ice Sheet. <br/><br/>Subglacial ecosystems, in particular subglacial lake ecosystems are extreme oligotrophic environments. These environments, and the ecosystems which may exist within them, should provide key insights into a range of fundamental questions about the development of Earth and other bodies in the Solar System including: 1) the processes associated with rapid evolutionary radiation after the extensive Neoproterozoic glaciations; 2) the overall carbon cycle through glacial and interglacial periods; and 3) the possible adaptations organisms may require to thrive in environments such as on Europa, the ice covered moon of Jupiter. Over 70 subglacial lakes have been identified beneath the 3-4 kilometer thick ice of Antarctica. One lake, Lake Vostok, is sufficiently large to be clearly identified from space with satellite altimetry. Lake Vostok is similar to Lake Ontario in area but with a much larger volume including measured water depths of 600 meters. The overlying ice sheet is acting as a conveyer belt continually delivering new water, nutrients, gas hydrates, sediments and microbes as the ice sheet flows across the lake. <br/><br/>The goal of this program is to determine the fundamental boundary conditions for this subglacial lake as an essential first step toward understanding the physical processes within the lake. An aerogeophysical survey over the lake and into the surrounding regions will be acquired to meet this goal. This data set includes gravity, magnetic, laser altimetry and ice penetrating radar data and will be used to compile a basic set of ice surface elevation, subglacial topography, gravity and magnetic anomaly maps. <br/><br/>Potential field methods widely used in the oil industry will be modified to estimate the subglacial topography from gravity data where the ice penetrating radar will be unable to recover the depth of the lake. A similar method can be modified to estimate the thickness of the sediments beneath the lake from magnetic data. These methods will be tested and applied to subglacial lakes near South Pole prior to the Lake Vostok field campaign and will provide valuable comparisons to the planned survey. Once the methods have been adjusted for the Lake Vostok application, maps of the water cavity and sediment thickness beneath the lake will be produced.<br/><br/>These maps will become tools to explore the geologic origin of the lake. The two endmember models are, first, that the lake is an active tectonic rift such as Lake Baikal and, second, the lake is the result of glacial scouring. The distinct characteristics of an extensional rift can be easily identified with our aerogeophysical survey. The geological interpretation of the airborne geophysical survey will provide the first geological constraints of the interior of the East Antarctic continent based on modern data. In addition, the underlying geology will influence the ecosystem within the lake. <br/><br/>One of the critical issues for the ecosystem within the lake will be the flux of nutrients. A preliminary estimation of the regions of freezing and melting based on the distance between distinctive internal layers observed on the radar data will be made. These basic boundary conditions will provide guidance for a potential international effort aimed at in situ exploration of the lake and improve the understanding of East Antarctic geologic structures.
Continental extension produces a great variety of structures from the linear narrow rifts of the East African Rift to the diffuse extension of the Basin and Range Province of the Western U.S. Rift shoulder uplift varies dramatically between rift flanks. The cause of variable rift width and crustal thinning is fairly well explained by variable initial heat flow and crustal thickness. Mechanical stretching of the lithosphere has been linked to rift shoulder uplift but the cause of variable rift flank uplift remains poorly understood. The Transantarctic Mountains (TAM) are an extreme example of rift flank uplift, extending over 3500 km across Antarctica and reaching elevations up to 4500 m and thus constitute a unique feature of EarthOs crust. The range was formed in the extensional environment associated with the Mesozoic and Cenozoic breakup of Gondwanaland. Geological and geophysical work has shown that the TAM developed along the long-lived lithospheric boundary between East and West Antarctica reactivated by a complex history of extensional and translational microplate motions. The TAM are not uniform along strike. Along the OWilkes FrontO, the northern segment of the rift extends from North Victoria Land to Byrd Glacier. The Wilkes Front architecture consists of (1) thin, extended crust forming the Victoria Land Basin in the Ross Sea, (2) the TAM rift shoulder, and (3) a long-wavelength down- ward forming the Wilkes Basin. Contrasting structures are mapped along the OPensacola/PoleO Front, the southern segment of the rift extending from the Nimrod Glacier to the Pensacola Mountains. Along this southern section no rift basin has been mapped to date and the down-ward along the East Antarctic, or ObacksideO, edge of the mountains is less pronounced. A flexural model linking the extension in the Ross Sea to the formation of both the mountains and the Wilkes Basin has been considered as a me chanism for uplift of the entire mountain range. The variability in fundamental architecture along the TAM indicates that neither a single event nor a sequence of identical events produced the rift flank uplift. The observation of variable architecture suggests complex mechanisms and possibly a fundamental limitation in maximum sustainable rift flank elevation. The motivation for studying the TAM is to try to understand the geodynamics of this extreme elevation rift flank. Are the geodynamics of the area unique, or does the history of glaciation and related erosion contribute to the extreme uplift? With the existing data sets it is difficult to confidently constrain the geological architecture across representative sections of the TAM. Any effort to refine geodynamic mechanisms requires this basic understanding of the TAM architecture. The goal of this project is to (1) constrain the architecture of the rift system as well as the distribution and structure of sedimentary basins, glacial erosion and mafic igneous rocks surrounding the rift flank by acquiring three long wavelength geophysical transects with integrated gravity, magnetics, ice- penetrating radar, and ice surface measurements, (2) quantify the contribution of various geodynamic mechanisms to understand the geological conditions which can lead to extreme rift flank uplift, and (3) use the improved understanding of architecture and geophysical data to test geodynamic models in order to improve our understanding both of the TAM geodynamics and the general problem of the geodynamics of rift flank uplift worldwide. This project will allow development of a generalized framework for understanding the development of rift flank uplift as well as address the question of the specific geodynamic evolution of the TAM.
This award supports a project to conduct an integrated geophysical survey over a large portion of the West Antarctic Ice Sheet (WAIS) toward an understanding of the dynamic behavior of the ice sheet and the nature of the lithosphere beneath the ice sheet. West Antarctica is characterized by two kinds of the Earth s most dynamic systems, a continental rift (the West Antarctic Rift System) and a marine based ice sheet (the WAIS). Active continental rift systems, caused by divergent plate motions, result in thinned continental crust. Associated with the thin crust are fault-bounded sedimentary basins, active volcanism, and elevated heat flow. Marine ice sheets are characterized by rapidly moving streams of ice, penetrating and draining a slowly moving ice reservoir. Evidence left by past marine ice sheets indicates that they may have a strongly non- linear response to long-term climate change which results in massive and rapid discharges of ice. Understanding the evolution of the ice stream system and its interaction with the interior ice is the key to understanding this non-linear response. Subglacial geology and ice dynamics are generally studied in isolation, but evidence is mounting that the behavior of the West Antarctic ice streams may be closely linked to the nature of the underlying West Antarctic rift system. The fast moving ice streams appear to glide on a lubricating layer of water-saturated till. This till requires easily eroded sediment and a source of water, both of which may be controlled by the geology of the rift system; the sediments from the fault-bounded basins and the water from the elevated heat flux associated with active lithospheric extension. This project represents an interdisciplinary aerogeophysical study to characterize the lithosphere of the West Antarctic rift system beneath critical regions of the WAIS. The objective is to determine the effects of the rift architect ure, as manifested by the distribution of sedimentary basins and volcanic constructs, on the ice stream system. The research tool is a unique geophysical aircraft with laser altimetry, ice penetrating radar, aerogravity, and aeromagnetic systems integrated with a high precision kinematic GPS navigation system. It is capable of imaging both the surface and bed of the ice sheet while simultaneously measuring the gravity and magnetic signature of the subglacial lithosphere. Work to be done under this award will build on work already completed in the southern sector of central West Antarctica and it will focus on the region of the Byrd Subglacial Basin and Ice Stream D. The ice sheet in these regions is completely covered by satellite imagery and so this project will be integrated with remote sensing studies of the ice stream. The changing dynamics of Ice Stream D, as with other West Antarctic ice streams, seem to be correlated with changes in the morphological provinces of the underlying rift system. The experimental targets proceed from the divide of the interior ice, downstream through the onset of streaming to the trunk of Ice Stream D. This study will be coordinated with surface glaciological investigations of Ice Stream D and will be used to guide cooperative over-snow seismic investigations of the central West Antarctic rift system. The data will also be used to select a site for future deep ice coring along the crest of the WAIS. These data represent baseline data for long term global change monitoring work and represent crucial boundary conditions for ice sheet modeling efforts.
This award supports a collaborative project that combines air and ground geological-geophysical investigations to understand the tectonic and geological development of the boundary between the Ross Sea Rift and the Marie Byrd Land (MBL) volcanic province. The project will determine the Cenozoic tectonic history of the region and whether Neogene structures that localized outlet glacier flow developed within the context of Cenozoic rifting on the eastern Ross Embayment margin, or within the volcanic province in MBL. The geological structure at the boundary between the Ross Embayment and western MBL may be a result of: 1) Cenozoic extension on the eastern shoulder of the Ross Sea rift; 2) uplift and crustal extension related to Neogene mantle plume activity in western MBL; or a combination of the two. Faulting and volcanism, mountain uplift, and glacier downcutting appear to now be active in western MBL, where generally East-to-West-flowing outlet glaciers incise Paleozoic and Mesozoic bedrock, and deglaciated summits indicate a previous North-South glacial flow direction. This study requires data collection using SOAR (Support Office for Aerogeophysical Research, a facility supported by Office of Polar Programs which utilizes high precision differential GPS to support a laser altimeter, ice-penetrating radar, a towed proton magnetometer, and a Bell BGM-3 gravimeter). This survey requires data for 37,000 square kilometers using 5.3 kilometer line spacing with 15.6 kilometer tie lines, and 86,000 square kilometers using a grid of 10.6 by 10.6 kilometer spacing. Data will be acquired over several key features in the region including, among other, the eastern edge of the Ross Sea rift, over ice stream OEO, the transition from the Edward VII Peninsula plateau to the Ford Ranges, the continuation to the east of a gravity high known from previous reconnaissance mapping over the Fosdick Metamorphic Complex, an d the extent of the high-amplitude magnetic anomalies (volcanic centers?) detected southeast of the northern Ford Ranges by other investigators. SOAR products will include glaciology data useful for studying driving stresses, glacial flow and mass balance in the West Antarctic Ice Sheet (WAIS). The ground program is centered on the southern Ford Ranges. Geologic field mapping will focus on small scale brittle structures for regional kinematic interpretation, on glaciated surfaces and deposits, and on datable volcanic rocks for geochronologic control. The relative significance of fault and joint sets, the timing relationships between them, and the probable context of their formation will also be determined. Exposure ages will be determined for erosion surfaces and moraines. Interpretation of potential field data will be aided by on ground sampling for magnetic properties and density as well as ground based gravity measurements. Oriented samples will be taken for paleomagnetic studies. Combined airborne and ground investigations will obtain basic data for describing the geology and structure at the eastern boundary of the Ross Embayment both in outcrop and ice covered areas, and may be used to distinguish between Ross Sea rift- related structural activity from uplift and faulting on the perimeter of the MBL dome and volcanic province. Outcrop geology and structure will be extrapolated with the aerogeophysical data to infer the geology that resides beneath the WAIS. The new knowledge of Neogene tectonics in western MBL will contribute to a comprehensive model for the Cenozoic Ross rift and to understanding of the extent of plume activity in MBL. Both are important for determining the influence of Neogene tectonics on the ice streams and WAIS.
Antarctic notothenioid fishes exhibit two adaptive traits to survive in frigid temperatures. The first of these is the production of anti-freeze proteins in their blood and tissues. The second is a system-wide ability to perform cellular and physiological functions at extremely cold temperatures.The proposal goals are to show how Antarctic fishes use these characteristics to avoid freezing, and which additional genes are turned on, or suppressed in order for these fishes to maintain normal physiological function in extreme cold temperatures. Progressively colder habitats are encountered in the high latitude McMurdo Sound and Ross Shelf region, along with somewhat milder near?shore water environments in the Western Antarctic Peninsula (WAP). By quantifying the extent of ice crystals invading and lodging in the spleen, the percentage of McMurdo Sound fish during austral summer (Oct-Feb) will be compared to the WAP intertidal fish during austral winter (Jul-Sep) to demonstrate their capability and extent of freeze avoidance. Resistance to ice entry in surface epithelia (e.g. skin, gill and intestinal lining) is another expression of the adaptation of these fish to otherwise lethally freezing conditions.<br/><br/>The adaptive nature of a uniquely characteristic polar genome will be explored by the study of the transcriptome (the set of expressed RNA transcripts that constitutes the precursor to set of proteins expressed by an entire genome). Three notothenioid species (E.maclovinus, D. Mawsoni and C. aceratus) will be analysed to document evolutionary genetic changes (both gain and loss) shaped by life under extreme chronic cold. A differential gene expression (DGE) study will be carried out on these different species to evaluate evolutionary modification of tissue-wide response to heat challenges. The transcriptomes and other sequencing libraries will contribute to de novo ice-fish genome sequencing efforts.
The goal of this project is to understand the drivers of pair disruption and quantify its resulting effects on individual fitness components and population growth rate and structure for two procellariiformes breeding in the Southern Ocean: the wandering albatross and the snow petrel, which both form long-lasting pair bonds. The mechanisms of pair disruption may be contrasted between these species, as pair disruption in wandering albatross may occur with the death of a partner by incidental by-catch in fisheries, while in snow petrels it may occur through divorce and climate-related conditions. Unique long-term individual mark-recapture data sets exist for these iconic polar species, allowing for a comprehensive study of the rates, causes and consequences of pair disruption and how they differ among species.
This study will result in the most detailed analysis to date of the impact of social monogamy and long-term pair bonds on individual fitness components (vital rates: survival, recruitment and fecundity; life-history outcomes: life expectancy, age at 1st breeding and lifetime reproductive success; and occupancy times: duration of pair bond or widowhood) and population growth and structure (e.g, sex ratio of individuals available for mating). Specifically, the investigators will assess:
1. Variations in pair disruption rates, and if they are related to global change (by-catch in the case of albatross widowing, and climate in the case of petrel divorce) by developing a state-of-the-art statistical multievent mark-recapture model.
2. Impacts of pair disruption on vital rates, specifically whether i) greater familiarity and better coordination within pairs improves breeding performance and survival, ii) mating costs reduce the probability of breeding and iii) divorce is more likely to occur after a breeding failure.
3. Impacts of pair disruption on life-history outcomes and occupancy times using Markov chain stochastic life cycle models.
4. Impacts of pair disruption on population dynamics by developing a novel non-linear two-sex matrix population model.
The investigators will develop novel sensitivity and Life Table Response Experiment analyses to examine the respective effects of fisheries, climate, vital rates, and pair-disruption rates on life-history outcomes, occupancy times, and population growth and structure, and their variations among year and species.
Melting of snow and ice at the surface of the Antarctic ice sheet can lead to the formation of meltwater lakes, an important precursor to ice-shelf collapse and accelerated ice-sheet mass loss. Understanding the present state of Antarctic surface melt provides a baseline to gauge how quickly melt impacts could evolve in the future and to reduce uncertainties in estimates of future sea-level rise. This project will use a suite of complimentary measurements from Earth-observing satellites, ground observations, and numerical climate and ice-shelf models to enhance understanding of surface melt and lakes, as well as the processes linking these systems. The project directly supports the scientific training of a postdoctoral associate and several undergraduate researchers. In addition, it will promote public scientific literacy and the broadening of quantitative skills for high-school students through the development and implementation of an educational unit in a partnership with an education and outreach expert and two high school teachers.<br/><br/>Accurate prediction of sea-level contributions from Antarctica critically requires understanding current melting and supraglacial lake conditions. This project will quantify Antarctic surface melt and supraglacial lakes, and the linkages between the two phenomena. Scatterometer data will enable generation of a 19-year multi-sensor melt time series. Synthetic aperture radar data will document melt conditions across all Antarctic ice shelves at the highest spatial resolution to date (40 m). Multispectral satellite imagery will be used to delineate and measure the depth of supraglacial lakes--for the first time studying the spatial and temporal variations of Antarctic supraglacial lakes. Melt and lake observations will be compared to identify agreement and disagreement. Melt observations will be used to evaluate biases in a widely used, reanalysis-driven, regional climate model. This model will then be used to examine climatic and glaciological variables associated with supraglacial lakes. Finally, in situ observations and climate model output will drive a numerical model that simulates the entire lifecycle of surface melt and possible subsequent lake formation.
Terra Nova Bay (western Ross Sea, Antarctica) supports dense populations of several key species in the Ross Sea food web, including copepods, crystal krill (Euphausia crystallorophias), Antarctic silverfish (Pleuragramma antarcticum), and colonies of Adélie and Emperor penguins that feed primarily on crystal krill and silverfish. Absent from our understanding of the Ross Sea food web is zooplankton and silverfish mesoscale distribution, spatial structure of age/maturity classes, and their interactions with physical drivers and each other. The quantitative linkages between primary producers and the higher trophic levels, specifically, the processes responsible for the regulation of abundance and rates of middle trophic levels dominated by copepods and crystal krill (Euphausia crystallorophias), is virtually unknown. Given that the next century will see extensive changes in the Ross Sea’s ice distributions and oceanography as a result of climate change, understanding the basic controls of zooplankton and silverfish abundance and distribution is essential.
During a January – March 2018 cruise in the western Ross Sea, we deployed a glider equipped with an echo sounder (Acoustic Zooplankton Fish Profiler) that simultaneously measured depth, temperature, conductivity, chlorophyll fluorescence, and dissolved oxygen. Additionally, net tows, mid-water trawls, and crystal krill grazing experiments were conducted. Our study provided the first glider-based acoustic assessment of simultaneous distributions of multiple trophic levels in the Ross Sea, from which predator-prey interactions and the relationships between organisms and physics drivers (sea ice, circulation features) were investigated. We illustrated high variability in ocean physics, phytoplankton biomass, and crystal krill biomass and aggregation over time and between locations within Terra Nova Bay. Biomass of krill was highest in locations characterized by deeper mixed layers and highest integrated chlorophyll concentrations. Krill aggregations were consistently located at depth well below the mixed layer and chlorophyll maximum. Experiments investigating krill grazing, in combination with krill depth distributions relative to chlorophyll biomass, illuminate high krill grazing rates could be attributed to the occupation of a unique niche whereby they are opportunistically feeding on sinking high concentrations of detritus derived from surface blooms. The information on the abundance, distribution, and interactions of key species in multiple trophic levels resulting from this project provide a conceptual background to understand how this ecosystem might respond to future conditions under climate change.
Our project tested the capability of a multi-frequency echo sounder on a glider for the first time. The production of consistent, vertically-resolved, high resolution glider-based acoustic measurements will pave the way for cost-effective, automated examination of entire food webs and ecosystems in regions all over the global ocean. A wide range of users including academic and government scientists, ecosystem-based fisheries managers, and monitoring programs including those conducted by OOI, IOOS, and NOAA will benefit from this project. This project also provided the opportunity to focus on broadening participation in research and articulating the societal benefits through education and innovative outreach programs. A data set from this project is being included in the new NSF-funded Polar CAP initiative, that will be used by a diverse and young audience to increase understanding of the polar system and the ability to reason with data. Finally, this project provided a unique field opportunity and excellent hand-on training for a post-doctoral researcher, a graduate student, and two undergraduate students.
The depths at which magmas are stored, their pre-eruptive volatile contents, and the rates at which they ascend to the Earth's surface are important controls on the dynamics of volcanic eruptions. Basaltic magmas are likely to be vapor undersaturated as they begin their ascent from the mantle through the crust, but volatile solubility drops with decreasing pressure. Once vapor saturation is achieved and the magma begins to degas, its pre-eruptive volatile content is determined largely by the depth at which it resides within the crust. Magma stored in deeper reservoirs tend to experience less pre-eruptive degassing and to be richer in volatiles than magma shallower reservoirs. Eruptive style is influenced by the rate at which a magma ascends from the reservoir to the surface through its effect on the efficiency of vapor bubble nucleation, growth, and coalescence. The proposed work will advance our understanding of pre-eruptive storage conditions and syn-eruptive ascent rates through a combined field and analytical research program. Volatile measurements from olivine-hosted melt inclusions will be used to systematically investigate magma storage depths and ascent rates associated with alkaline volcanism in the Erebus volcanic province. A central goal of the project is to provide a spatial and temporal framework for interpreting results from studies of present-day volcanic processes at Mt Erebus volcano. The Erebus volcanic province of Antarctica is especially well suited to this type of investigation because: (1) there are many exposed mafic scoria cones, fissure vents, and hyaloclastites (exposed in sea cliffs) that produced rapidly quenched, olivine-rich tephra; (2) existing volatile data for Ross Island MIs show that magma storage was relatively deep compared to many mafic volcanic systems; (3) some of the eruptive centers ejected mantle xenoliths, allowing for comparison of ascent rates for xenolith-bearing and xenolith-free eruptions, and comparison of ascent rates for those bearing xenoliths with times estimated from settling velocities; and (4) the cold, dry conditions in Antarctica result in excellent tephra preservation compared to tropical and even many temperate localities. The project provides new tools for assessing volcanic hazards, facilitates collaboration involving researchers from three different institutions (WHOI, U Wyoming, and U Oregon), supports the researchers' involvement in teaching, advising, and outreach, and provides an educational opportunity for a promising young postdoctoral researcher. Understanding the interrelationships among magma volatile contents, reservoir depths, and ascent rates is vital for assessing volcanic hazards associated with alkaline volcanism across the globe.
This project developed sediment provenance proxies to trace the sources of sediment discharged by the WAIS to the continental rise. The WAIS erodes sediments from various West Antarctic geologic terranes that are deposited in adjacent drift sites. The geochemistry and magnetic properties of drift sediments reflect the tectono-metamorphic history of their source terranes. Deglaciation of a terrane during WAIS collapse should be detectable by the loss of the terrane’s geochemical and magnetic signature in continental-rise detrital sediments. Continental shelf late-Holocene sediments from near the current WAIS groundling line were analyzed for silt- and claysize Sr-Nd-Pb isotopes and major-trace elements. The suite of cores spans from the eastern Ross Sea to the northern tip of the Antarctic Peninsula and established the provenance signatures of the Ross and Amundsen Provinces of Marie Byrd Land, Pine Island Bay, Thurston Island/Eight Coast Block, Ellsworth-Whitmore Crustal Block, and Antarctic Peninsula terranes. Many of these terranes have similar tectono-metamorphic histories but Sr-Nd isotope data from detrital sediments suggest at least 3 distinct provenance signatures. This comprehensive grain-size-specific provenance data adds to on-going collection of glacial till mineral and bulk provenance data. An initial down core study of Ocean Drilling Program Site 1096 in the Bellingshausen Sea was used to assess the utility of these new grain-size-specific provenance proxies in documenting WAIS collapse. We found the presence of both the WAIS and APIS over the last 115,000 years, but absence of the WAIS before 115,000 years ago. This means that the WAIS was gone during the last interglacial period, an interval when sea level was at least 6 meters above present.
Considerable uncertainty remains in projections of future ice loss from West Antarctica. A recent decadal style U.S. National Academy of Sciences, Engineering, and Medicine report entitled: A Strategic Vision for NSF Investments in Antarctic and Southern Ocean Research (2015) identifies changing ice in Antarctica as one of the highest priority science problems facing communities around the globe. The report identifies Thwaites Glacier as a target for collaborative intense research efforts in the coming years. This project contributes to that effort by deploying an instrument on board airborne surveys that will help to constrain the unknown terrains beneath the Thwaites Ice Shelf and in the region of the grounding line where the inland ice goes afloat. By improving the accuracy and resolution of these data, which are fed into predictive numerical models, the team will help to constrain the magnitude and rate of increase in the contribution of ice from Thwaites Glacier to the global ocean.<br/><br/>The team will enhance the capabilities of the already planned British Antarctic Survey aerogeophysics survey of Thwaites Glacier during the 2018/19 field season. Their Inertial Measurement Unit will be paired with a state-of-the-art commercial gravity meter to acquire high-quality and significantly enhanced resolution data both over the ice shelf and at the grounding line. Data will be processed immediately following collection and raw and observed data will be released six months after collection.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Current oceanographic interest in the interaction of relatively warm water of the Southern Ocean Circumpolar Deep Water (CDW) as it moves southward to the frigid waters of the Antarctic continental shelves is based on the potential importance of heat transport from the global ocean to the base of continental ice shelves. This is needed to understand the longer term mass balance of the continent, the stability of the vast Antarctic ice sheets and the rate at which sea-level will rise in a warming world. Improved observational knowledge of the mechanisms of how warming CDW moves across the Antarctic Circumpolar Current (ACC) is needed. Understanding this dynamical transport, believed to take place through the eddy flux of time-varying mesoscale circulation features, will improve coupled ocean-atmospheric climate models. The development of the next generation of coupled ocean-ice-climate models help us understand future changes in atmospheric heat fluxes, glacial and sea-ice balance, and changes in the Antarctic ecosystems. A recurring obstacle to our understanding is the lack of data in this distant region. In this project, a total of 10 subsurface profiling EM-APEX floats adapted to operate under sea ice were launched in 12 missions (and 2 recoveries) from 4 cruises of opportunity to the Amundsen Sea sector of the Antarctic continental margin during Austral summer. The floats were launched south of the Polar Front and measured shear, turbulence, temperature, and salinity to 2000m depth for 1-2 year missions while drifting with the CDW layer between profiles.
Antarctic fish and their early developmental stages are an important component of the food web that sustains life in the cold Southern Ocean (SO) that surrounds Antarctica. They feed on smaller organisms and in turn are eaten by larger animals, including seals and killer whales. Little is known about how rising ocean temperatures will impact the development of Antarctic fish embryos and their growth after hatching. This project will address this gap by assessing the effects of elevated temperatures on embryo viability, on the rate of embryo development, and on the gene "toolkits" that respond to temperature stress. One of the two species to be studied does not produce red blood cells, a defect that may make its embryos particularly vulnerable to heat. The outcomes of this research will provide the public and policymakers with "real world" data that are necessary to inform decisions and design strategies to cope with changes in the Earth's climate, particularly with respect to protecting life in the SO. The project will also further the NSF goals of training new generations of scientists, including providing scientific training for undergraduate and graduate students, and of making scientific discoveries available to the general public. This includes the unique educational opportunity for undergraduates to participate in research in Antarctica and engaging the public in several ways, including the development of professionally-produced educational videos with bi-lingual
closed captioning.
Since the onset of cooling of the SO about 40 million years ago, evolution of Antarctic marine organisms has been driven by the development of cold temperatures. Because body temperatures of Antarctic fishes fall in a narrow range determined by their habitat (-1.9 to +2.0 C), they are particularly attractive models for understanding how organismal physiology and biochemistry have been shaped to maintain life in a cooling environment. Yet these fishes are now threatened by rapid warming of the SO. The long-term objective of this project is to understand the capacities of Antarctic fishes to acclimatize and/or adapt to oceanic warming through analysis of their underlying genetic "toolkits." This objective will be accomplished through three Specific Aims: 1) assessing the effects of elevated temperatures on gene expression during development of embryos; 2) examining the effects of elevated temperatures on embryonic morphology and on the temporal and spatial patterns of gene expression; and 3) evaluating the evolutionary mechanisms that have led to the loss of the red blood cell genetic program by the white-blooded fishes. Aims 1 and 2 will be investigated by acclimating experimental embryos of both red-blooded and white-blooded fish to elevated temperatures. Differential gene expression will be examined through the use of high throughput RNA sequencing. The temporal and spatial patterns of gene expression in the context of embryonic morphology (Aim 2) will be determined by microscopic analysis of embryos "stained" with (hybridized to) differentially expressed gene probes revealed by Aim 1; other key developmental marker genes will also be used. The genetic lesions resulting from loss of red blood cells by the white-blooded fishes (Aim 3) will be examined by comparing genes and genomes in the two fish groups.
Subduction takes place at convergent plate boundaries and involves sinking of one tectonic plate underneath another. Although this process is a key aspect of plate tectonics that shapes the planet over geologic time, and is a primary cause of earthquakes, it is not known what causes subduction to cease, and what effect it has on the deepest portions of the crust and the upper part of the mantle. By studying the age and composition of igneous rocks emplaced at the very end of the subduction cycle, this project seeks to understand what causes subduction to cease, and how this changes the composition and structure of the crust and upper mantle. Because this process occurs deep within the earth, the project will focus on rocks in the root of an ancient subduction zone, now exposed in the Transantarctic Mountains of Antarctica. In addition, Antarctica remains relatively poorly understood, and this project will contribute directly to increasing our understanding of the geologic history of this region. The project will focus on training graduate and undergraduate students - incorporating hands-on experience with an array of state-of-the-art analytical instrumentation. Students will also gain a range of more general skills including Geographic Information Systems (GIS), written and oral communication, and data management - strengths that are highly relevant to careers both in the academic and Geosciences industry. Each summer, high school students will be incorporated into aspects of the laboratory-based research through the UCSB research mentorship program. The PI and graduate students will engage the general public through a purpose-built iPhone App and multimedia website. Activities will include live phone and video conversations from the field between elementary school students and members of the team in Antarctica. <br/><br/>The mechanisms by which the deep crustal delaminates or "founders" and is returned to the mantle remains a fundamental problem in earth science. Specifically, little is known about the temporal and spatial scales over which this process occurs or the mechanisms that trigger such catastrophic events. Igneous rocks highly enriched in potassium, called lamprophyres, are often emplaced during, and immediately after, termination of subduction and therefore potentially provide direct insight into foundering. These enigmatic rocks are important because they represent near-primary mantle melt compositions and therefore their age, geochemistry and petrologic evolution reveal key information on both the composition of the upper mantle and its thermal state. Of equal importance, they reveal how these key parameters vary through both space and time. By evaluating lamprophyres along a subduction zone margin it is possible to extract: 1) local-scale information, such as the timing and duration of melting and the role of igneous crystallization processes in generation of isotopic heterogeneities; 2) along-strike variations in mantle source composition, temperature, and depth of melting 3) the plate-scale forces that control foundering and termination of subduction. This project will study a suite of lamprophyres along the axis of the Transantarctic Mountains, emplaced during the latest stages of the Neoproterozoic - Ordovician Ross orogeny, Antarctica (roughly 505 to 470 million years before present). High-precision geochronology (age determinations) will be combined with geochemical measurements on the rocks and minerals to understand the mechanisms and timing of deep crustal foundering/delamination.
Beginning with the discovery of a "curious valley" in 1903 by Captain Scott, the McMurdo Dry Valleys (MDV) in Antarctica have been impacted by humans, although there were only three brief visits prior to 1950. Since the late 1950's, human activity in the MDV has become commonplace in summer, putting pressure on the region's fragile ecosystems through camp construction and inhabitation, cross-valley transport on foot and via vehicles, and scientific research that involves sampling and deployment of instruments. Historical photographs, put alongside information from written documentation, offer an invaluable record of the changing patterns of human activity in the MDV. Photographic images often show the physical extent of field camps and research sites, the activities that were taking place, and the environmental protection measures that were being followed. Historical photographs of the MDV, however, are scattered in different places around the world, often in private collections, and there is a real danger that many of these photos may be lost, along with the information they contain. This project will collect and digitize historical photographs of sites of human activity in the MDV from archives and private collections in the United States, New Zealand, and organize them both chronologically and spatially in a GIS database. Sites of past human activities will be re-photographed to provide comparisons with the present, and re-photography will assist in providing spatial data for historical photographs without obvious location information. The results of this analysis will support effective environmental management into the future. The digital photo archive will be openly available through the McMurdo Dry Valleys Long Term Ecological Research (MCM LTER) website (www.mcmlter.org), where it can be used by scientists, environmental managers, and others interested in the region. <br/><br/>The central question of this project can be reformulated as a hypothesis: Despite an overall increase in human activities in the MDV, the spatial range of these activities has become more confined over time as a result of an increased awareness of ecosystem fragility and efforts to manage the region. To address this hypothesis, the project will define the spatial distribution and temporal frequency of human activity in the MDV. Photographs and reports will be collected from archives with polar collections such as the National Archives of New Zealand in Wellington and Christchurch and the Byrd Polar Research Center in Ohio. Private photograph collections will be accessed through personal connections, social media, advertisements in periodicals such as The Polar Times, and other means. Re-photography in the field will follow established techniques and will create benchmarks for future research projects. The spatial data will be stored in an ArcGIS database for analysis and quantification of the human footprint over time in the MDV. The improved understanding of changing patterns of human activity in the MDV provided by this historical photo archive will provide three major contributions: 1) a fundamentally important historic accounting of human activity to support current environmental management of the MDV; 2) defining the location and type of human activity will be of immediate benefit in two important ways: a) places to avoid for scientists interested in sampling pristine landscapes, and, b) targets of opportunity for scientists investigating the long-term environmental legacy of human activity; and 3) this research will make an innovative contribution to knowledge of the environmental history of the MDV.
This project contributes to the joint initiative launched by the U.S. National Science Foundation (NSF) and the U.K. Natural Environment Research Council (NERC) to substantially improve decadal and longer-term projections of ice loss and sea-level rise originating from Thwaites Glacier in West Antarctica. Satellite observations extending over the last 25 years show that Thwaites Glacier is rapidly thinning and accelerating. Over this same period, the Thwaites grounding line, the point at which the glacier transitions from sitting on the seabed to floating, has retreated. Oceanographic studies demonstrate that the main driver of these changes is incursion of warm water from the deep ocean that flows beneath the floating ice shelf and causes basal melting. The period of satellite observation is not long enough to determine how a large glacier, such as Thwaites, responds to long-term and near-term changes in the ocean or the atmosphere. As a result, records of glacier change from the pre-satellite era are required to build a holistic understanding of glacier behavior. Ocean-floor sediments deposited at the retreating grounding line and further offshore contain these longer-term records of changes in the glacier and the adjacent ocean. An additional large unknown is the topography of the seafloor and how it influences interactions of landward-flowing warm water with Thwaites Glacier and affects its stability. Consequently, this project focuses on the seafloor offshore from Thwaites Glacier and the records of past glacial and ocean change contained in the sediments deposited by the glacier and surrounding ocean.<br/><br/>Uncertainty in model projections of the future of Thwaites Glacier will be significantly reduced by cross-disciplinary investigations seaward of the current grounding line, including extracting the record of decadal to millennial variations in warm water incursion, determining the pre-satellite era history of grounding-line migration, and constraining the bathymetric pathways that control flow of warm water to the grounding line. Sedimentary records and glacial landforms preserved on the seafloor will allow reconstruction of changes in drivers and the glacial response to them over a range of timescales, thus providing reference data that can be used to initiate and evaluate the reliability of models. Such data will further provide insights on the influence of poorly understood processes on marine ice sheet dynamics. This project will include an integrated suite of marine and sub-ice shelf research activities aimed at establishing boundary conditions seaward of the Thwaites Glacier grounding line, obtaining records of the external drivers of change, improving knowledge of processes leading to collapse of Thwaites Glacier, and determining the history of past change in grounding line migration and conditions at the glacier base. These objectives will be achieved through high-resolution geophysical surveys of the seafloor and analysis of sediments collected in cores from the inner shelf seaward of the Thwaites Glacier grounding line using ship-based equipment, and from beneath the ice shelf using a corer deployed through the ice shelf via hot water drill holes.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Cryoconite holes are pockets of life completely encased in otherwise barren glacial ice. These pockets of life form when dust blown onto the ice melts a small, largely isolated hole that can function as its own tiny ecosystem. This dust can contain microorganisms such as bacteria, algae, or microscopic animals. The microorganisms within the hole interact and carry out functions typical of a larger ecosystem, such as a forest. Cryoconite holes are especially important in extreme cold environments such as the Antarctic Dry Valleys, where they function as repositories of life. Because cryoconite holes are mostly enclosed and persist for years, they can be tracked over time to test fundamental scientific questions about how communities of interacting organisms develop to become fully functioning ecosystems. This project will sample existing and experimentally created cryoconite holes to understand how these ecosystems develop and to what degree random processes (such as which organisms get there first) affect the final community composition and functioning. The results will not only improve our understanding of how microbial communities assemble and affect the functioning of microecosystems such as cryoconite holes, but also how the processes of community assembly affect functioning of larger ecosystems, such as forests. A better understanding of community establishment, development, and response to abiotic factors are essential to forecasting ecological responses to environmental change.<br/><br/>It is essential to unravel the links between community assembly, biodiversity, and nutrient cycling across numerous ecosystems because these are critical factors determining ecological responses to environmental change. The unique, largely isolated nature of cryoconite holes provides an experimental system that will advance fundamental understanding of the processes (e.g., stochastic dynamics such as dispersal limitation, assembly order, and ecological drift) driving community assembly. This project will use a field sampling campaign and a number of manipulative experiments to test a hypothesis that unites theory in community and ecosystem ecology: the degree to which stochastic processes guide microbial community assembly and affects regional patterns in biodiversity and ecosystem processes. Cryoconite holes will be sampled to compare community composition, environmental factors, and ecosystem functioning between hydrologically connected and isolated holes. New cryoconite holes will also be constructed and monitored over the course of two growing seasons to specifically alter assembly order and community size, thereby pairing a unique manipulative experiment with field surveys to address questions with relevance to the Antarctic and beyond. Amplicon sequencing, metagenomics, microscopy, sensitive environmental chemistry methods, and photosynthesis and respiration measurements will be used to test a series of sub-hypotheses that relate stochasticity to patterns in regional biodiversity, heterogeneity in environmental factors, and ecosystem processes.
This proposal requests support for a project to drill and recover a new ice core from South Pole, Antarctica. The South Pole ice core will be drilled to a depth of 1500 m, providing an environmental record spanning approximately 40 kyrs. This core will be recovered using a new intermediate drill, which is under development by the U.S. Ice Drilling Design and Operations (IDDO) group in collaboration with Danish scientists. This proposal seeks support to provide: 1) scientific management and oversight for the South Pole ice core project, 2) personnel for ice core drilling and core processing, 3) data management, and 3) scientific coordination and communication via scientific workshops. The intellectual merit of the work is that the analysis of stable isotopes, atmospheric gases, and aerosol-borne chemicals in polar ice has provided unique information about the magnitude and timing of changes in climate and climate forcing through time. The international ice core research community has articulated the goal of developing spatial arrays of ice cores across Antarctica and Greenland, allowing the reconstruction of regional patterns of climate variability in order to provide greater insight into the mechanisms driving climate change. The broader impacts of the project include obtaining the South Pole ice core will support a wide range of ice core science projects, which will contribute to the societal need for a basic understanding of climate and the capability to predict climate and ice sheet stability on long time scales. Second, the project will help train the next generation of ice core scientists by providing the opportunity for hands-on field and core processing experience for graduate students and postdoctoral researchers. A postdoctoral researcher at the University of Washington will be directly supported by this project, and many other young scientists will interact with the project through individual science proposals. Third, the project will result in the development of a new intermediate drill which will become an important resource to US ice core science community. This drill will have a light logistical footprint which will enable a wide range of ice core projects to be carried out that are not currently feasible. Finally, although this project does not request funds for outreach activities, the project will run workshops that will encourage and enable proposals for coordinated outreach activities involving the South Pole ice core science team.
Earth's geologic record shows that the great ice sheets have contributed to rates of sea-level rise that have been much higher than those observed today. That said, some sectors of the current Antarctic ice sheet are losing mass at large and accelerating rates. One of the primary challenges for placing these recent and ongoing changes in the context of geologically historic rates, and for making projections decades to centuries into the future, is the difficulty of observing conditions and processes beneath the ice sheet. Whereas satellite observations allow tracking of the ice-surface velocity and elevation on the scale of glacier catchments to ice sheets, airborne ice-penetrating radar has been the only approach for assessing conditions on this scale beneath the ice. These radar observations have been made since the late 1960s, but, because many different instruments have been used, it is difficult to track change in subglacial conditions through time. This project will develop the technical tools and approaches required to cross-compare among these measurements and thus open up opportunities for tracking and understanding changes in the critical subglacial environment. Intertwined with the research and student training on this project will be an outreach education effort to provide middle school and high school students with improved resources and enhanced exposure to geophysical, glaciological, and remote-sensing topics through partnership with the National Science Olympiad.<br/><br/>The radar sounding of ice sheets is a powerful tool for glaciological science with broad applicability across a wide range of cryosphere problems and processes. Radar sounding data have been collected with extensive spatial and temporal coverage across the West Antarctic Ice Sheet, including areas where multiple surveys provide observations that span decades in time or entire cross-catchment ice-sheet sectors. However, one major obstacle to realizing the scientific potential of existing radar sounding observations in Antarctica is the lack of analysis approaches specifically developed for cross-instrument interpretation. Radar is also spatially limited and often has gaps of many tens of kilometers between data points. Further work is needed to investigate ways of extrapolating radar information beyond the flight lines. This project aims to directly address these barriers to full utilization of the collective Antarctic radar sounding record by developing a suite of processing and interpretation techniques to enable the synthesis of radar sounding data sets collected with systems that range from incoherent to coherent, single-channel to swath-imaging, and digital to optically-recorded radar sounders. This includes a geostatistical analysis of ice sheet and radar datasets to make probabilistic predictions of conditions at the bed. The approaches will be assessed for two target regions: the Amundsen Sea Embayment and the Siple Coast. All pre- and post-processed sounding data produced by this project will be publically hosted for use by the wider research community.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Accurate reconstructions and predictions of glacier movement on timescales of human interest require a better understanding of available observations and the ability to model the key processes that govern ice flow. The fact that many of these processes are interconnected, are loosely constrained by data, and involve not only the ice, but also the atmosphere, ocean, and solid Earth, makes this a challenging endeavor, but one that is essential for Earth-system modeling and the resulting climate and sea-level forecasts that are provided to policymakers worldwide. Based on the amount of ice present in the West Antarctic Ice Sheet and its ability to flow and/or melt into the ocean, its complete collapse would result in a global sea-level rise of 3.3 to 5 meters, making its stability and rate of change scientific questions of global societal significance. Whether or not a collapse eventually occurs, a better understanding of the potential West Antarctic contribution to sea level over the coming decades and centuries is necessary when considering the fate of coastal population centers. Recent observations of the Amundsen Sea Embayment of West Antarctica indicate that it is experiencing faster mass loss than any other region of the continent. At present, the long-term stability of this embayment is unknown, with both theory and observations suggesting that collapse is possible. This study is focused on this critical region as well as processes governing changes in outlet glacier flow. To this end, we will test an ice-sheet model against existing observations and improve treatment of key processes within ice sheet models.
This is a four-year (one year of no-cost extension) modeling study using the open-source Ice Sheet System Model in coordination with other models to help improve projections of future sea-level change. Overall project goals, which are distributed across the collaborating institutions, are to:
1. hindcast the past two-to-three decades of evolution of the Amundsen Sea Embayment sector to determine controlling processes, incorporate and test parameterizations, and assess and improve model initialization, spinup, and performance;
2. utilize observations from glacial settings and efficient process-oriented models to develop a better understanding of key processes associated with outlet glacier dynamics and to create numerically efficient parameterizations for these often sub-grid-scale processes;
3. project a range of evolutions of the Amundsen Sea Embayment sector in the next several centuries given various forcings and inclusion or omission of physical processes in the model.
The response of the Antarctic Ice Sheet to future climatic changes is recognized as the greatest uncertainty in projections of future sea level. An understanding of past ice fluctuations affords insight into ice-sheet response to climate and sea-level change and thus is critical for improving sea-level predictions. This project will examine deglaciation of the southern Ross Sea over the past few thousand years to document oscillations in Antarctic ice volume during a period of relatively stable climate and sea level. We will help quantify changes in ice volume, improve understanding of the ice dynamics responsible, and examine the implications for future sea-level change. The project will train future scientists through participation of graduate students, as well as undergraduates who will develop research projects in our laboratories.<br/><br/>Previous research indicates rapid Ross Sea deglaciation as far south as Beardmore Glacier early in the Holocene epoch (which began approximately 11,700 years before present), followed by more gradual recession. However, deglaciation in the later half of the Holocene remains poorly constrained, with no chronological control on grounding-line migration between Beardmore and Scott Glaciers. Thus, we do not know if mid-Holocene recession drove the grounding line rapidly back to its present position at Scott Glacier, or if the ice sheet withdrew gradually in the absence of significant climate forcing or eustatic sea level change. The latter possibility raises concerns for future stability of the Ross Sea grounding line. To address this question, we will map and date glacial deposits on coastal mountains that constrain the thinning history of Liv and Amundsen Glaciers. By extending our chronology down to the level of floating ice at the mouths of these glaciers, we will date their thinning history from glacial maximum to present, as well as migration of the Ross Sea grounding line southwards along the Transantarctic Mountains. High-resolution dating will come from Beryllium-10 surface-exposure ages of erratics collected along elevation transects, as well as Carbon-14 dates of algae within shorelines from former ice-dammed ponds. Sites have been chosen specifically to allow close comparison of these two dating methods, which will afford constraints on Antarctic Beryllium-10 production rates.
This collaborative project explores the signatures and causes of natural climate change in the region surrounding Antarctica over the last 40,000 years as the Earth transitioned from an ice age into the modern warm period. The researchers will investigate how the wind belts that surround Antarctica changed in their strength and position through time, and document explosive volcanic eruptions and CO2 cycling in the Southern Ocean as potential climate forcing mechanisms over this interval. Understanding how and why the climate varied naturally in the past is critical for improving understanding of modern climate change and projections of future climate under higher levels of atmospheric CO2. <br/><br/>The investigators plan to conduct a suite of chemical measurements along the 1500m length of the South Pole Ice Core, including major ion and trace element concentrations, and microparticle (dust) concentrations and size distributions. These measurements will (1) extend the South Pole record of explosive volcanic eruptions to 40,000 years using sulfate and particle data; (2) establish the relative timing of climate changes in dust source regions of Patagonia, New Zealand, and Australia using dust flux data; (3) investigate changes in the strength and position of the westerly wind belt using dust size distribution data; and (4) quantify the flux of bioavailable trace metals deposited as dust to the Southern Ocean over time. These chemistry records will also be critical for creating the timescale that will be used by all researchers studying records from the South Pole core. The project will support four graduate students and several undergraduate students across three different institutions, and become a focus of the investigators' efforts to disseminate outcomes of climate change science to the broader community.
The Antarctic marine ecosystem is highly productive and supports a diverse range of ecologically and commercially important species. A key species in this ecosystem is Antarctic krill, which in addition to being commercially harvested, is the principle prey of a wide range of marine organisms including penguins, seals and whales. The aim of this study is to use penguins and other krill predators as sensitive indicators of past changes in the Antarctic marine food web resulting from climate variability and the historic harvesting of seals and whales by humans. Specifically this study will recover and analyze modern (<20 year old), historic (20-200 year old) and ancient (200-10,000 year old) penguin and other krill predator tissues to track their past diets and population movements relative to shifts in climate and the availability of Antarctic krill. Understanding how krill predators were affected by these factors in the past will allow us to better understand how these predators, the krill they depend on, and the Antarctic marine ecosystem as a whole will respond to current challenges such as global climate change and an expanding commercial fishery for Antarctic krill. The project will further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. This project will support the cross-institutional training of undergraduate and graduate students in advanced analytical techniques in the fields of ecology and biogeochemistry. In addition, this project includes educational outreach aimed encouraging participation in science careers by engaging K-12 students in scientific issues related to Antarctica, penguins, marine ecology, biogeochemistry, and global climate change.<br/><br/>This research will help place recent ecological changes in the Southern Ocean into a larger historical context by examining decadal and millennial-scale shifts in the diets and population movements of Antarctic krill predators (penguins, seals, and squid) in concert with climate variability and commercial harvesting. This will be achieved by coupling advanced stable and radio isotope techniques, particularly compound-specific stable isotope analysis, with unprecedented access to modern, historical, and well-preserved paleo-archives of Antarctic predator tissues dating throughout the Holocene. This approach will allow the project to empirically test if observed shifts in Antarctic predator bulk tissue stable isotope values over the past millennia were caused by climate-driven shifts at the base of the food web in addition to, or rather than, shifts in predator diets due to a competitive release following the historic harvesting of krill eating whale and seals. In addition, this project will track the large-scale abandonment and reoccupation of penguin colonies around Antarctica in response to changes in climate and sea ice conditions over the past several millennia. These integrated field studies and laboratory analyses will provide new insights into the underlying mechanisms that influenced past shifts in the diets and population movements of charismatic krill predators such as penguins. This will allow for improved projections of the ecosystem consequences of future climate change and anthropogenic harvesting scenarios in the Antarctica that are likely to affect the availability of Antarctic krill.
Phytoplankton blooms in the coastal waters of the Ross Sea, Antarctica are typically dominated by either diatoms or Phaeocystis Antarctica (a flagellated algae that often can form large colonies in a gelatinous matrix). The project seeks to determine if an association of bacterial populations with Phaeocystis antarctica colonies can directly supply Phaeocystis with Vitamin B12, which can be an important co-limiting micronutrient in the Ross Sea. The supply of an essential vitamin coupled with the ability to grow at lower iron concentrations may put Phaeocystis at a competitive advantage over diatoms. Because Phaeocystis cells can fix more carbon than diatoms and Phaeocystis are not grazed as efficiently as diatoms, the project will help in refining understanding of carbon dynamics in the region as well as the basis of the food web webs. Such understanding also has the potential to help refine predictive ecological models for the region. The project will conduct public outreach activities and will contribute to undergraduate and graduate research. Engagement of underrepresented students will occur during summer student internships. A collaboration with Italian Antarctic researchers, who have been studying the Terra Nova Bay ecosystem since the 1980s, aims to enhance the project and promote international scientific collaborations. <br/><br/>The study will test whether a mutualistic symbioses between attached bacteria and Phaeocystis provides colonial cells a mechanism for alleviating chronic Vitamin B12 co-limitation effects thereby conferring them with a competitive advantage over diatom communities. The use of drifters in a time series study will provide the opportunity to track in both space and time a developing algal bloom in Terra Nova Bay and to determine community structure and the physiological nutrient status of microbial populations. A combination of flow cytometry, proteomics, metatranscriptomics, radioisotopic and stable isotopic labeling experiments will determine carbon and nutrient uptake rates and the role of bacteria in mitigating potential vitamin B12 and iron limitation. Membrane inlet and proton transfer reaction mass spectrometry will also be used to estimate net community production and release of volatile organic carbon compounds that are climatically active. Understanding how environmental parameters can influence microbial community dynamics in Antarctic coastal waters will advance an understanding of how changes in ocean stratification and chemistry could impact the biogeochemistry and food web dynamics of Southern Ocean ecosystems.
Abstract<br/>During the Early Pliocene, 4.8 to 3.4 million years ago, warmer-than-present global temperatures resulted in a retreat of the Ross Ice Shelf and West Antarctic Ice Sheet. Understanding changes in ocean dynamics during times of reduced ice volume and increased temperatures in the geologic past will improve the predictive models for these conditions. The primary goal of the proposed research is to develop a new oxygen isotope record of Pliocene oceanographic conditions near the Antarctic continent. Oxygen isotope values from the carbonate tests of benthic foraminifera have become the global standard for paleo-oceanographic studies, but foraminifera are sparse in high-latitude sediment cores. This research will instead make use of oxygen isotope measurements from diatom silica preserved in a marine sediment core from the Ross Sea. The project is the first attempt at using this method and will advance understanding of global ocean dynamics and ice sheet-ocean interactions during the Pliocene. The project will foster the professional development of two early-career scientists and serve as training for graduate and undergraduate student researchers. The PIs will use this project to introduce High School students to polar/oceanographic research, as well as stable isotope geochemistry. Collaboration with teachers via NSTA and Polar Educators International will ensure the implementation of excellent STEM learning activities and curricula for younger students. <br/><br/>Technical Description<br/>This project will produce a high-resolution oxygen isotope record from well-dated diatom rich sediments that have been cross-correlated with global benthic foraminifera oxygen isotope records. Diatom silica frustules deposited during the Early Pliocene and recovered by the ANDRILL Project (AND-1B) provide ideal material for this objective. Diatomite unites in the AND-1B core are nearly pure, with little evidence of opal formation. A diatom oxygen isotope record from this core offers the potential to constrain lingering uncertainties about Ross Sea and Southern Ocean paleoceanography and Antarctic Ice Sheet history during a time of high atmospheric carbon dioxide concentrations. Specifically, oxygen isotope variations will be used to constrain changes in the water temperature and/or freshwater flux in the Pliocene Ross Sea. Diatom species data from the AND-1B core have been used to infer variations in the extent and duration of seasonal sea ice coverage, sea surface temperatures, and mid-water advection onto the continental shelf. However, the diatom oxygen isotope record will provide the first direct measure of water/oxygen isotope values at the Antarctic continental margin during the Pliocene.
The Weddell seal is the southern-most mammal in the world, having a circumpolar distribution around Antarctica; the McMurdo Sound population in Antarctica is one of the best-studied mammal populations on earth. However, despite this, an understanding of how populations around the continent will fare under climate change is poorly understood. A complicating matter is the potential effects of a commercial enterprise in the Antarctic: a fishery targeting toothfish, which are important prey for Weddell seals. Although the species is easily detected and counted during the breeding season, no reliable estimates of continent-wide Weddell seal numbers exist, due to the logistic difficulties of surveying vast regions of Antarctica. Large-scale estimates are needed to understand how seal populations are responding to the fishery and climate change, because these drivers of change operate at scales larger than any single population, and may affect seals differently in different regions of the continent. We will take advantage of the ease of detectability of darkly colored seals when they the on ice to develop estimates of abundance from satellite images. This project will generate baseline data on the global distribution and abundance of Weddell seals around the Antarctic and will link environmental variables to population changes to better understand how the species will fare as their sea ice habitat continues to change. These results will help disentangle the effects of climate change and fishery operations, results that are necessary for appropriate international policy regarding fishery catch limits, impacts on the environment, and the value of marine protected areas. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. It will engage "arm-chair" scientists of all ages through connections with several non-governmental organizations and the general public. Anyone with access to the internet, including people who are physically unable to participate in field research directly, can participate in this project while simultaneously learning about multiple aspects of polar ecology through the project's interactive website. <br/><br/>Specifically, this research project will: 1) Quantify the distribution of Weddell seals around Antarctica and 2) Determine the impact of environmental variables (such as fast ice extent, ocean productivity, bathymetry) on habitat suitability and occupancy. To do this, the project will crowd-source counting of seals on high-resolution satellite images via a commercial citizen science platform. Variation in seal around the continent will then be related to habitat variables through generalized linear models. Specific variables, such as fast ice extent will be tested to determine their influence on population variability through both space and time. The project includes a rigorous plan for ensuring quality control in the dataset including ground truth data from other, localized projects concurrently funded by the National Science Foundation's Antarctic Science Program.
Rapid changes in the extent and thickness of sea ice during the austral spring subject microorganisms within or attached to the ice to large fluctuations in temperature, salinity, light and nutrients. This project aims to identify cellular responses in sea-ice algae to increasing temperature and decreasing salinity during the spring melt along the western Antarctic Peninsula and to determine how associated changes at the cellular level can potentially affect dynamic, biologically driven processes. Understanding how sea-ice algae cope with, and are adapted to, their environment will not only help predict how polar ecosystems may change as the extent and thickness of sea ice change, but will also provide a better understanding of the widespread success of photosynthetic life on Earth. The scientific context and resulting advances from the research will be communicated to the general public through outreach activities that includes work with Science Communication Fellows and the popular Polar Science Weekend at the Pacific Science Center in Seattle, Washington. The project will provide student training to college students as well as provide for educational experiences for K-12 school children. <br/><br/><br/>There is currently a poor understanding of feedback relationships that exist between the rapidly changing environment in the western Antarctic Peninsula region and sea-ice algal production. The large shifts in temperature and salinity that algae experience during the spring melt affect critical cellular processes, including rates of enzyme-catalyzed reactions involved in photosynthesis and respiration, and the production of stress-protective compounds. These changes in cellular processes are poorly constrained but can be large and may have impacts on local ecosystem productivity and biogeochemical cycles. In particular, this study will focus on the thermal sensitivity of enzymes and the cycling of compatible solutes and exopolymers used for halo- and cryo-protection, and how they influence primary production and the biogeochemical cycling of carbon and nitrogen. Approaches will include field sampling during spring melt, incubation experiments of natural sea-ice communities under variable temperature and salinity conditions, and controlled manipulation of sea-ice algal species in laboratory culture. Employment of a range of techniques, from fast repetition rate fluorometry and gross and net photosynthetic measurements to metabolomics and enzyme kinetics, will tease apart the mechanistic effects of temperature and salinity on cell metabolism and primary production with the goal of quantifying how these changes will impact biogeochemical processes along the western Antarctic Peninsula.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Overview: The funded work investigated whether ice core 86Kr acts as a proxy for barometric pressure variability, and whether this proxy can be used in Antarctic ice cores to infer past movement of the Southern Hemisphere (SH) westerly winds. Pressure variations drive macroscopic air movement in the firn column, which reduces the gravitational isotopic enrichment of slow-diffusing gases (such as Kr). The 86Kr deviation from gravitational equilibrium (denoted D86Kr) thus reflects the magnitude of pressure variations (among other things). Atmospheric reanalysis data suggest that pressure variability over Antarctica is linked to the Southern Annular Mode (SAM) index and the position of the SH westerly winds. Preliminary data from the WAIS Divide ice core show a large excursion in D86Kr during the last deglaciation (20-9 ka before present). In this project the investigators (1) performed high-precision 86Kr analysis on ice core and firn air samples to establish whether D86Kr is linked to pressure variability; (2) Refined the deglacial WAIS Divide record of Kr isotopes; (3) Investigated the role of pressure variability in firn air transport using firn air models with firn microtomography data and Lattice- Boltzmann modeling; and (4) Investigated how barometric pressure variability in Antarctica is linked to the SAM index and the position/strength of the SH westerlies in past and present climates using GCM and reanalysis data. A key finding was that D86Kr in recent ice samples (e.g. last 50 years) from a broad spatial array of sites in Antarctica and Greenland showed a significant correlation with directly measured barometric pressure variability at the ice core site. This strongly supports the hypothesis that 86Kr can be used as a paleo-proxy for storminess.
Intellectual Merit: The SH westerlies are a key component of the global climate system; they are an important control on the global oceanic overturning circulation and possibly on atmospheric CO2 concentrations. Poleward movement of the SH westerlies during the last deglaciation has been hypothesized, yet evidence from proxy and modeling studies remains inconclusive. The funded work could provide valuable new constraints on deglacial movement of the SH westerlies. This record can be compared to high-resolution CO2 data from the same core, allowing us to test hypotheses that link CO2 to the SH westerlies. Climate proxies are at the heart of paleoclimate research. The funded work has apparently led to the discovery of a completely new proxy, opening up exciting new research possibilities and increasing the scientific value of existing ice cores. Once validated, the 86Kr proxy could be applied to other time periods as well, providing a long-term perspective on the movement of the SH westerlies. The funded work has furthermore provided valuable new insights into firn air transport.
Broader impact: The Southern Ocean is presently an important sink of atmospheric CO2, thereby reducing the warming associated with anthropogenic CO2 emissions. Stratospheric ozone depletion and greenhouse warming have displaced the SH westerlies poleward, with potential consequences for the future magnitude of this oceanic carbon uptake. The funded work may provide a paleo-perspective on past movement of the SH westerlies and its link to atmospheric CO2, which could guide projections of future oceanic CO2 uptake, with strong societal benefits. The awarded funds supported and trained an early-career postdoctoral scholar at OSU, and fostered (international) collaboration. Data from the study will be available to the scientific community and the broad public through recognized data centers. During this project the PI and senior personnel have continued their commitment to public outreach through media interviews and speaking to schools and the public about their work. The PI provides services to the community by chairing the IPICS (International Partnership in Ice Core Sciences) working group and organizing annual PIRE (Partnerships in International Research and Education) workshops.
The Ross Ice Shelf is the largest existing ice shelf in Antarctica, and is currently stabilizing significant portions of the land ice atop the Antarctic continent. An ice shelf begins where the land ice goes afloat on the ocean, and as such, the Ross Ice Shelf interacts with the ocean and seafloor below, and the land ice behind. Currently, the Ross Ice Shelf slows down, or buttresses, the fast flowing ice streams of the West Antarctic Ice Sheet (WAIS), a marine-based ice sheet, which if melted, would raise global sea level by 3-4 meters. The Ross Ice Shelf average ice thickness is approximately 350 meters, and it covers approximately 487,000 square kilometers, an area slightly larger than the state of California. The Ross Ice Shelf has disappeared during prior interglacial periods, suggesting in the future it may disappear again. Understanding the dynamics, stability and future of the West Antarctic Ice Sheet therefore requires in-depth knowledge of the Ross Ice Shelf. The ROSETTA-ICE project brings together scientists from 4 US institutions and from the Institute of Geological and Nuclear Sciences Limited, known as GNS Science, New Zealand. The ROSETTA-ICE data on the ice shelf, the water beneath the ice shelf, and the underlying rocks, will allow better predictions of how the Ross Ice Shelf will respond to changing climate, and therefore how the WAIS will behave in the future. The interdisciplinary ROSETTA-ICE team will train undergraduate and high school students in cutting edge research techniques, and will also work to educate the public via a series of vignettes integrating ROSETTA-ICE science with the scientific and human history of Antarctic research.<br/><br/>The ROSETTA-ICE survey will acquire gravity and magnetics data to determine the water depth beneath the ice shelf. Radar, LIDAR and imagery systems will be used to map the Ross Ice Shelf thickness and fine structure, crevasses, channels, debris, surface accumulation and distribution of marine ice. The high resolution aerogeophysical data over the Ross Ice Shelf region in Antarctica will be acquired using the IcePod sensor suite mounted externally on an LC-130 aircraft operating from McMurdo Station, Antarctica. Field activities will include ~36 flights on LC-130 aircraft over two field seasons in Antarctica. The IcePod instrument suite leverages the unique experience of the New York Air National Guard operating in Antarctica for NSF scientific research as well as infrastructure and logistics. The project will answer questions about the stability of the Ross Ice Shelf in future climate, and the geotectonic evolution of the Ross Ice Shelf Region, a key component of the West Antarctic Rift system. The comprehensive benchmark data sets acquired will enable broad, interdisciplinary analyses and modeling, which will also be performed as part of the project. ROSETTA-ICE will illuminate Ross ice sheet-ice shelf-ocean dynamics as the system nears a critical juncture but still is intact. Through interacting with an online data visualization tool, and comparing the ROSETTA-ICE data and results from earlier studies, we will engage students and young investigators, equipping them with new capabilities for the study of critical earth systems that influence global climate.
The one place on Earth consistently showing increases in sea ice area, duration, and concentration is the Ross Sea in Antarctica. Satellite imagery shows about half of the Ross Sea increases are associated with changes in the austral fall, when the new sea ice is forming. The most pronounced changes are also located near polynyas, which are areas of open ocean surrounded by sea ice. To understand the processes driving the sea ice increase, and to determine if the increase in sea ice area is also accompanied by a change in ice thickness, this project will conduct an oceanographic cruise to the polynyas of the Ross Sea in April and May, 2017, which is the austral fall. The team will deploy state of the art research tools including unmanned airborne systems (UASs, commonly called drones), autonomous underwater vehicles (AUVs), and remotely operated underwater vehicles (ROVs). Using these tools and others, the team will study atmospheric, oceanic, and sea ice properties and processes concurrently. A change in sea ice production will necessarily change the ocean water below, which may have significant consequences for global ocean circulation patterns, a topic of international importance. All the involved institutions will be training students, and all share the goal of expanding climate literacy in the US, emphasizing the role high latitudes play in the Earth's dynamic climate.<br/><br/>The main goal of the project is to improve estimates of sea ice production and water mass transformation in the Ross Sea. The team will fully capture the spatial and temporal changes in air-ice-ocean interactions when they are initiated in the austral fall, and then track the changes into the winter and spring using ice buoys, and airborne mapping with the newly commissioned IcePod instrument system, which is deployed on the US Antarctic Program's LC-130 fleet. The oceanographic cruise will include stations in and outside of both the Terra Nova Bay and Ross Ice Shelf polynyas. Measurements to be made include air-sea boundary layer fluxes of heat, freshwater, and trace gases, radiation, and meteorology in the air; ice formation processes, ice thickness, snow depth, mass balance, and ice drift within the sea ice zone; and temperature, salinity, and momentum in the ocean below. Following collection of the field data, the team will improve both model parameterizations of air-sea-ice interactions and remote sensing algorithms. Model parameterizations are needed to determine if sea-ice production has increased in crucial areas, and if so, why (e.g., stronger winds or fresher oceans). The remote sensing validation will facilitate change detection over wider areas and verify model predictions over time. Accordingly this project will contribute to the international Southern Ocean Observing System (SOOS) goal of measuring essential climate variables continuously to monitor the state of the ocean and ice cover into the future.
Intellectual Merit:
Evidence from the eastern Ross Sea continental shelf indicates that the West Antarctic Ice Sheet advanced and retreated during the last glacial cycle, but it is unclear whether the ice sheet advanced to the shelf edge or just to the middle shelf. These two end-member scenarios offer different interpretations as to why, how, and when the West Antarctic Ice Sheet oscillated. The PI proposes to acquire seismic, multibeam, and core data from Whales Deep, to evaluate the timing and duration of two advances of grounded ice to the outer and middle shelf of the Whales Deep Basin, a West Antarctic Ice Sheet paleo ice stream trough in eastern Ross Sea. Grounding events are represented by seismically resolvable Grounding Zone Wedges. The PI will collect radiocarbon dates on in situ benthic foraminifera from the grounding zone diamict as well as ramped pyrolysis radiocarbon dates on acid insoluble organics from open-marine mud overlying the grounding zone diamict. Using these data the PI will calculate the duration of the two grounding events. Furthermore, the PI will test a numerical model prediction that West Antarctic Ice Sheet retreat must have involved melting at the marine terminus of the ice sheet. Pore-water from the grounding zone diamict will be extracted from piston cores to determine salinity and δ18O values that should indicate if significant melting occurred at the grounding line.
Broader impacts:
The data collected will provide constraints on the timing and pattern of Last Glacial Maximum advance and retreat that can be incorporated into interpretations of ice-surface elevation changes. The proposed activities will provide valuable field and research training to undergraduate/graduate students and a Louisiana high-school science teacher. The research will be interactively shared with middle- and high-school science students and with visitors to the LSU Museum of Natural Science Weekend-Science Program.
The McMurdo Dry Valleys, Antarctica, are a mosaic of terrestrial and aquatic ecosystems in a cold desert. The McMurdo Long Term Ecological Research (LTER) project has been observing these ecosystems since 1993 and this award will support key long-term measurements, manipulation experiments, synthesis, and modeling to test current theories on ecosystem structure and function. Data collection is focused on meteorology and physical and biological dimensions of soils, streams, lakes, glaciers, and permafrost. The long-term measurements show that biological communities have adapted to the seasonally cold, dark, and arid conditions that prevail for all but a short period in the austral summer. Physical (climate and geological) drivers impart a dynamic connectivity among portions of the Dry Valley landscape over seasonal to millennial time scales. For instance, lakes and soils have been connected through cycles of lake-level rise and fall over the past 20,000 years while streams connect glaciers to lakes over seasonal time scales. Overlaid upon this physical system are biotic communities that are structured by the environment and by the movement of individual organisms within and between the glaciers, streams, lakes, and soils. The new work to be conducted at the McMurdo LTER site will explore how the layers of connectivity in the McMurdo Dry Valleys influence ecosystem structure and function.
This project will test the hypothesis that increased ecological connectivity following enhanced melt conditions within the McMurdo Dry Valleys ecosystem will amplify exchange of biota, energy, and matter, homogenizing ecosystem structure and functioning. This hypothesis will be tested with new and continuing experiments that examine: 1) how climate variation alters connectivity among landscape units, and 2) how biota are connected across a heterogeneous landscape using state-of-the-science tools and methods including automated sensor networks, analysis of seasonal satellite imagery, biogeochemical analyses, and next-generation sequencing. McMurdo LTER education programs and outreach activities will be continued, and expanded with new programs associated with the 200th anniversary of the first recorded sightings of Antarctica. These activities will advance societal understanding of how polar ecosystems respond to change. McMurdo LTER will continue its mission of training and mentoring students, postdocs, and early career scientists as the next generation of leaders in polar ecosystem science, and lead the development of international environmental stewardship protocols for human activities in the region.
Methane is a potent greenhouse gas that is naturally emitted into the oceans by geologic seeps and microbial production. Based on studies of persistent deep-sea seeps at mid- and northern latitudes, researchers have learned that bacteria and archaea can create a "sediment filter" that oxidizes methane prior to its release. Antarctica is thought to contain large reservoirs of organic carbon buried beneath its ice which could a quantity of methane equivalent to all of the permafrost in the Arctic and yet we know almost nothing about the methane oxidizing microbes in this region. How these microbial communities develop and potentially respond to fluctuations in methane levels is an under-explored avenue of research. A bacterial mat was recently discovered at 78 degrees south, suggesting the possible presence of a methane seep, and associated microbial communities. This project will explore this environment in detail to assess the levels and origin of methane, and the nature of the microbial ecosystem present. <br/> <br/>An expansive bacterial mat appeared and/or was discovered at 78 degrees south in 2011. This site, near McMurdo Station Antarctica, has been visited since the mid-1960s, but this mat was not observed until 2011. The finding of this site provides an unusual opportunity to study an Antarctic marine benthic habitat with active methane cycling and to examine the dynamics of recruitment and community succession of seep fauna including bacteria, archaea, protists and metazoans. This project will collect the necessary baseline data to facilitate further studies of Antarctic methane cycling. The concentration and source of methane will be determined at this site and at potentially analogous sites in McMurdo Sound. In addition to biogeochemical characterization of the sites, molecular analysis of the microbial community will quantify the time scales on which bacteria and archaea respond to methane input and provide information on rates of community development and succession in the Southern Ocean. Project activities will facilitate the training of at least one graduate student and results will be shared at both local and international levels. A female graduate student will be mentored as part of this project and data collected will form part of her dissertation. Lectures will be given in K-12 classrooms in Oregon to excite students about polar science. National and international audiences will be reached through blogs and presentations at a scientific conference. The PI's previous blogs have been used by K-12 classrooms as part of their lesson plans and followed in over 65 countries.<br/>
Omelon, Christopher; Breecker, Daniel; Bennett, Philip
No dataset link provided
Cryptoendoliths are organisms that colonize microscopic cavities of rocks, which give them protection and allow them to inhabit extreme environments, such as the cold, arid desert of the Dry Valleys of Antarctica. Fossilized cryptoendoliths preserve the forms and features of organisms from the past and thus provide a unique opportunity to study the organisms' life histories and environments. To study this fossil record, there needs to be a better understanding of what environmental conditions allow these fossils to form. A climate gradient currently exists in the Dry Valleys that allows us to study living, dead, and fossilized cryptoendoliths from mild to increasingly harsh environments; providing insight to the limits of life and how these fossils are formed. This project will develop instruments to detect the biological activity of the live microorganisms and conduct laboratory experiments to determine the environmental limits of their survival. The project also will characterize the chemical and structural features of the living, dead, and fossilized cryptoendoliths to understand how they become fossilized. Knowing how microorganisms are preserved as fossils in cold and dry environments like Antarctica can help to refine methods that can be used to search for and identify evidence for extraterrestrial life in similar habitats on planets such as Mars. This project includes training of graduate and undergraduate students.
Little is known about cryptoendolithic microfossils and their formation processes in cold, arid terrestrial habitats of the Dry Valleys of Antarctica, where a legacy of activity is discernible in the form of biosignatures including inorganic materials and microbial fossils that preserve and indicate traces of past biological activity. The overarching goals of the proposed work are: (1) to determine how rates of microbial respiration and biodegradation of organic matter control microbial fossilization; and (2) to characterize microbial fossils and their living counterparts to elucidate mechanisms for fossilization. Using samples collected across an increasingly harsher (more cold and dry) climatic gradient that encompasses living, dead, and fossilized cryptoendolithic microorganisms, the proposed work will: (1) develop an instrument to be used in the field that can measure small concentrations of CO2 in cryptoendolithic habitats in situ; (2) use microscopy techniques to characterize endolithic microorganisms as well as the chemical and morphological characteristics of biosignatures and microbial fossils. A metagenomic survey of microbial communities in these samples will be used to characterize differences in diversity, identify if specific microorganisms (e.g. prokaryotes, eukaryotes) are more capable of surviving under these harsh climatic conditions, and to corroborate microscopic observations of the viability states of these microorganisms.
Recent observations and model results suggest that collapse of the Amundsen Sea sector of West Antarctica may already be underway. However, the timeline of collapse and the effects of ongoing climatic and oceanographic changes are key unanswered questions. Complete disintegration of the ice sheet would raise global sea level by more than 3 m, which would have significant societal impacts. Improved understanding of the controls on ice-sheet evolution is needed to make better predictions of ice-sheet behavior. Results from numerical models show that buttressing from surrounding ice shelves and/or from small-scale grounded ice rises should act to slow the retreat and discharge of ice from the interior ice sheet. However, there are very few field observations with which to develop and validate models. Field observations conducted in the early 1980s on Crary Ice Rise in the Ross Sea Embayment are a notable exception. This project will revisit Crary Ice Rise with new tools to make a suite of measurements designed to address questions about how the ice rise affects ice discharge from the Ross Sea sector of West Antarctica. The team will include a graduate and undergraduate student, and will participate in a range of outreach activities.<br/><br/>New tools including radar, seismic, and GPS instruments will be used to conduct targeted geophysical measurements both on Crary Ice Rise and across its grounding line. The project will use these new measurements, together with available ancillary data to inform a numerical model of grounding line dynamics. The model and measurements will be used to address the (1) How has the ice rise evolved over timescales ranging from: the past few decades; the past millennia after freeze-on; and through the deglaciation? (2) What history of ice dynamics is preserved in the radar-detected internal stratigraphy? (3) What dynamical effect does the presence/absence of the ice rise have on discharge of the Ross Ice Streams today? (4) How is it contributing to the slow-down of the proximal Whillans and Mercer ice streams? (5) What dynamical response will the ice rise have under future environmental change?
In order to understand what environmental conditions might look like for future generations, we need to turn to archives of past times when the world was indeed warmer, before anyone was around to commit them to collective memory. The geologic record of Earth's past offers a glimpse of what could be in store for the future. Research by Ivany and her team looks to Antarctica during a time of past global warmth to see how seasonality of temperature and rainfall in coastal settings are likely to change in the future. They will use the chemistry of fossils (a natural archive of these variables) to test a provocative hypothesis about near-monsoonal conditions in the high latitudes when the oceans are warm. If true, we can expect high-latitude shipping lanes to become more hazardous and fragile marine ecosystems adapted to constant cold temperatures to suffer. With growing information about how human activities are likely to affect the planet in the future, we will be able to make more informed decisions about policies today. This research involves an international team of scholars, including several women scientists, training of graduate students, and a public museum exhibit to educate children about how we study Earth's ancient climate and what we can learn from it.<br/><br/>Antarctica is key to an understanding how Earth?s climate system works under conditions of elevated CO2. The poles are the most sensitive regions on the planet to climate change, and the equator-to-pole temperature gradient and the degree to which high-latitude warming is amplified are important components for climate models to capture. Accurate proxy data with good age control are therefore critical for testing numerical models and establishing global patterns. The La Meseta Formation on Seymour Island is the only documented marine section from the globally warm Eocene Epoch exposed in outcrop on the continent; hence its climate record is integral to studies of warming. Early data suggest the potential for strongly seasonal precipitation and runoff in coastal settings. This collaboration among paleontologists, geochemists, and climate modelers will test this using seasonally resolved del-18O data from fossil shallow marine bivalves to track the evolution of seasonality through the section, in combination with independent proxies for the composition of summer precipitation (leaf wax del-D) and local seawater (clumped isotopes). The impact of the anticipated salinity stratification on regional climate will be evaluated in the context of numerical climate model simulations. In addition to providing greater clarity on high-latitude conditions during this time of high CO2, the combination of proxy and model results will provide insights about how Eocene warmth may have been maintained and how subsequent cooling came about. As well, a new approach to the analysis of shell carbonates for 87Sr/86Sr will allow refinements in age control so as to allow correlation of this important section with other regions to clarify global climate gradients. The project outlined here will develop new and detailed paleoclimate records from existing samples using well-tuned as well as newer proxies applied here in novel ways. Seasonal extremes are climate parameters generally inaccessible to most studies but critical to an understanding of climate change; these are possible to resolve in this well-preserved, accretionary-macrofossil-bearing section. This is an integrated study that links marine and terrestrial climate records for a key region of the planet across the most significant climate transition in the Cenozoic.
Since the advent of Antarctic continental glaciation, the opening of the Drake Passage between South America and the Antarctic Peninsula, and the onset of cooling of the Southern Ocean ~40-25 million years ago, evolution of the Antarctic marine biota has been driven by the development of extreme cold temperatures. As circum-Antarctic coastal temperatures declined during this period from ~20°C to the modern -1.9 to +2.0°C (reached ~8-10 million years ago), the psychrophilic (cold-loving) ectotherms of the Southern Ocean evolved compensatory molecular, cellular, and physiological traits that enabled them to maintain normal metabolic function at cold temperatures. Today, these organisms are threatened by rapid warming of the Southern Ocean over periods measured in centuries (as much as 5°C/100 yr), a timeframe so short that re-adaptation and/or acclimatization to the "new warm" may not be possible. Thus, the long-term goals of this research project are: 1) to understand the biochemical and physiological capacities of the embryos of Antarctic notothenioid fish to resist or compensate for rapid oceanic warming; and 2) to assess the genetic toolkit available to support the acclimatization and adaptation of Antarctic notothenioid embryos to their warming habitat. The specific aims of this work are: 1) to determine the capacity of the chaperonin complex of notothenioid fishes to assist protein folding at temperatures between -4 and +20°C; and 2) to evaluate the genetic responses of notothenioid embryos, measured as global differential gene transcription, to temperature challenge, with -1.9°C as the "normal" control and +4 and +10°C as high temperature insults.
The physiology of embryonic development of marine stenotherms under future climate change scenarios is an important but understudied problem. This project will provide valuable insights into the capacity of Antarctic fish embryos to acclimatize and adapt to plausible climate change scenarios by examining multiple levels of biological organization, from the biochemical to the organismal. The results should also be broadly applicable to understanding the impact of global warming on marine biota worldwide. The research will also introduce graduate and undergraduate students to state-of-the-art biochemical, cellular, and molecular-biological research relevant to ecological and environmental issues of the Antarctic marine ecosystem.
Ice shelves are the floating portions of glaciers that terminate in the ocean. They are common around the periphery of Antarctica. The accumulation of surface meltwater on or near the surface of ice shelves can play a role in ice-shelf collapse, which leads to accelerated loss of grounded ice and sea-level rise. Recent studies have showed that present-day meltwater generation and movement across the surface of Antarctica is more widespread than previously thought and is expected to increase. Consequently, there is a growing need to address the role of surface water in forecasts of ice-shelf behavior. While much progress has been made, understanding of the role of water in ice-shelf collapse is still in its infancy. This award supports a workshop that will bring together experts from multiple disciplines that, together, can advance understanding of Antarctic surface hydrology and its role in the future stability of ice shelves. This workshop will bring together U.S. and international scientists with expertise in ice-sheet dynamics, glacial hydrology, climatology, and other disciplines to identify critical knowledge gaps and move the community towards answering fundamental questions such as: What climate dynamics are responsible for surface meltwater generation in Antarctica? What controls the spatiotemporal distribution of meltwater ponds on Antarctic ice shelves? Where is meltwater generated, where does it pond today, and how will this change this century? How will meltwater impact ice shelves? How will surface hydrology impact sea-level this century? The deliberations will be captured in a workshop report.
Intellectual Merit:<br/>Ice free rock outcrops in the Transantarctic Mountains provide the only accessible windows into the interior of the ice covered Antarctic continent; they are extremely remote and difficult to study. This region also hosts the highest latitude ice-free valley systems on the planet. Based on two interdisciplinary workshops, the Transantarctic region near the Shackleton Glacier has been identified as a high priority site for further studies, with a field camp proposed for the 2015-2016 Antarctic field season. The geology of this region has been studied since the heroic era of Antarctic exploration, in the early 1900s, but geologic mapping has not been updated in more than forty years, and existing maps are at poor resolution (typically 1:250,000).<br/><br/>This project would utilize the WorldView-2 multispectral orbital dataset to supplement original geologic mapping efforts near the proposed 2015-2016 Shackleton Glacier camp. The WorldView-2 satellite is the only multispectral orbiting sensor capable of imaging the entirety of the Transantarctic Mountains, and all necessary data are currently available to the Polar Geospatial Center. High-latitude atmospheric correction of multispectral data for geologic investigations has only recently been tested, but has never been applied to WorldView-2 data, and never for observations of this type. Therefore, this research will require technique refinements and methodological developements to accomplish the goals. Atmospheric correction refinements and spectral validation will be made possible by laboratory spectroscopic measurements of rock samples currently stored at the U.S. Polar Rock Repository, at the Ohio State University. This project will result in spectral unit identification and boundary mapping at a factor of four higher resolution (1:62,500) than previous geologic mapping efforts, and more detailed investigations (1:5,123) are possible at resolutions more than a factor of forty-eight improved over previous geologic maps. Validated spectral mapping at these improved resolutions will allow for detailed lithologic, and potentially biologic, mapping using existing satellite imagery. This will greatly enhance planning capabilities, thus maximizing the efficiency of the scientific research and support logistics associated with the Shackleton Glacier deep field camp.<br/><br/>Broader impacts:<br/>The proposed work will have multiple impacts on the broader scientific community. First, the refinement of existing atmospheric correction methodologies, and the development of new spectral mapping techniques, may substantially improve our ability to remotely investigate geologic surfaces throughout Antarctica. The ability to validate this orbital dataset will be of use to both current and future geologic, environmental, and biologic studies, potentially across the entire continent. The project will yield a specific spectral mapping product (at a scale of 1:62,500) to the scientific community by a targeted date of 01 March 2014, in order to support proposals submitted to the National Science Foundation for the proposed 2015/2016 Shackleton Glacier camp. High-resolution spectral mapping products (up to a maximum resolution of 2 meters per pixel) will also be generated for regions of particular scientific interest. The use of community based resources, such as Polar Geospatial Center (PGC) imagery and U.S. Polar Rock Repository rock samples, will generate new synergistic and collaborative research possibilities within the Antarctic research community. In addition, the lead PI (Salvatore) is an early career scientist who is active in both Antarctic and planetary remote sensing. There are overlaps in the calibration, correction, and validation of remote spectral datasets for Antarctic and planetary applications which can lead to benefits and insights to an early career PI, as well as the two communities.
This project will study the dynamics of Circumpolar Deep Water intruding on the continental shelf of the West Antarctic coast, and the effect of this intrusion on the production of cold, dense bottom water, and melting at the base of floating glaciers and ice tongues. It will concentrate on the Amundsen Sea shelf, specifically in the region of the Pine Island Glacier, the Thwaites Glacier, and the Getz Ice Shelf. Circumpolar Deep Water (CDW) is a relatively warm water mass (warmer than +1.0 deg Celsius) which is normally confined to the outer edge of the continental shelf by an oceanic front separating this water mass from colder and saltier shelf waters. In the Amundsen Sea however, the deeper parts of the continental shelf are filled with nearly undiluted CDW, which is mixed upward, delivering significant amounts of heat to the base of the floating glacier tongues and the ice shelf. The melt rate beneath the Pine Island Glacier averages ten meters of ice per year with local annual rates reaching twenty meters. By comparison, melt rates beneath the Ross Ice Shelf are typically twenty to forty centimeters of ice per year. In addition, both the Pine Island and the Thwaites Glacier are extremely fast-moving, and have a significant effect on the regional ice mass balance of West Antarctica. This project therefore has an important connection to antarctic glaciology, particularly in assessing the combined effect of global change on the antarctic environment. The particular objectives of the project are (1) to delineate the frontal structure on the continental shelf sufficiently to define quantitatively the major routes of CDW inflow, meltwater outflow, and the westward evolution of CDW influence; (2) to use the obtained data set to validate a three-dimensional model of sub-ice ocean circulation that is currently under construction, and (3) to refine the estiamtes of in situ melting on the mass balance of the antarctic ice sheet. The observational program will be carried out from the research vessel Nathaniel B. Palmer in February and March, 1999.
Worldwide publicity surrounding the calving of an iceberg the size of Delaware in July 2017 from the Larsen C Ice Shelf on the eastern side of the Antarctic Peninsula presents a unique and time-sensitive opportunity for research and education on polar ecosystems in a changing climate. The goal of this project was to convene a workshop, drawing from the large fund of intellectual capital in the US and international Antarctic research communities. The two-day workshop was designed to bring scientists with expertise in Antarctic biological, ecological, and ecosystem sciences to Florida State University to share knowledge, identify important research knowledge gaps, and outline strategic plans for research.
Major outcomes from the project were as follows. The international workshop to share and review knowledge concerning the response of Antarctic ecosystems to ice-shelf collapse was held at the Florida State University Coastal and Marine Laboratory (FSUCML) on 18-19 November 2017. Thirty-eight U.S. and international scientists attended the workshop, providing expertise in biological, ecological, geological, biogeographical, and glaciological sciences. Twenty-six additional scientists were either not able to attend or were declined because of having reached maximum capacity of the venue or for not responding to our invitation before the registration deadline.
The latest results of ice-shelf research were presented, providing an overview of the current scientific knowledge and understanding of the biological, ecological,
geological and cryospheric processes associated with ice-shelf collapse and its
ecosystem-level consequences. In addition, several presentations focused on future plans to investigate the impacts of the recent Larsen C collapse. The following presentations were given at the meeting:
1) Cryospheric dynamics and ice-shelf collapse – past and future (M. Truffer,
University of Alaska, Fairbanks)
2) The geological history and geological impacts of ice-shelf collapse on the Antarctic Peninsula (Scottt Ishman, Amy Leventer)
3) Pelagic ecosystem responses to ice-shelf collapse (Mattias Cape, Amy Leventer)
4) Benthic ecosystem response to ice-shelf collapse (Craig Smith, Pavica Sršen, Ann Vanreusel)
5) Larsen C and biotic homogenization of the benthos (Richard Aronson, James
McClintock, Kathryn Smith, Brittany Steffel)
6) British Antarctic Survey: plans for Larsen C investigations early 2018 and in the
future (Huw Griffiths)
7) Feedback on the workshop “Climate change impacts on marine ecosystems:
implications for management of living resources and conservation” held 19-22
September 2017, Cambridge, UK (Alex Rogers)
8) Past research activities and plans for Larsen field work by the Alfred Wegener
Institute, Germany (Charlotte Havermans, Dieter Piepenburg.
One of the salient points emerging from the presentations and ensuing discussions was that, given our poor abilities to predict ecological outcomes of ice-shelf collapses, major cross-disciplinary efforts are needed on a variety of spatial and temporal scales to achieve a broader, predictive understanding of ecosystem
consequences of climatic warming and ice-shelf failure. As part of the workshop, the FSUCML Polar Academy Team—Dr. Emily Dolan, Dr. Heidi Geisz, Barbara Shoplock, and Dr. Jeroen Ingels—initiated AntICE: "Antarctic Influences of Climate Change on Ecosystems" (AntICE). They reached out to various groups of school children in the local area (and continue to do so). The AntICE Team have been interacting with these children at Wakulla High School and Wakulla Elementary in Crawfordville; children from the Cornerstone Learning Community, Maclay Middle School, Gilchrist Elementary, and the School of Arts and Sciences in Tallahassee; and the Tallahassee-area homeschooling community to educate them about Antarctic ecosystems and ongoing climate change. The underlying idea was to
make the children aware of climatic changes in the Antarctic and their effect on
ecosystems so they, in turn, can spread this knowledge to their communities, family
and friends – acting as ‘Polar Ambassadors’. We collaborated with the Polar-ICE
project, an NSF-funded educational project that established the Polar Literacy
Initiative. This program developed the Polar Literacy Principles, which outline
essential concepts to improve public understanding of Antarctic and Arctic
ecosystems. In the Polar Academy work, we used the Polar Literacy principles, the
Polar Academy Team’s own Antarctic scientific efforts, and the experience of the FSU outreach and education program to engage with the children. We focused on the importance of Antarctic organisms and ecosystems, the uniqueness of its biota and the significance of its food webs, as well as how all these are changing and will
change further with climate change. Using general presentations, case studies,
scientific methodology, individual experiences, interactive discussions and Q&A
sessions, the children were guided through the many issues Antarctic ecosystems
are facing. Over 300 'Polar ambassadors' attended the interactive lectures and
afterwards took their creativity to high latitudes by creating welcome letters, displays, dioramas, sculptures, videos and online media to present at the scientific workshop. Over 50 projects were created by the children (Please see supporting files for images). We were also joined by a photographer, Ryan David Reines, to document the event. More information, media and links to online outreach products are available at https://marinelab.fsu.edu/labs/ingels/outreach/polar-academy/
Understanding the ecological consequences - present and future-of climate change is a central question in conservation biology. The goal of this project is to identify the effects of climate change on the Black-Browed Albatross, a seabird breeding in the Southern Ocean. The Black-Browed Albatross exhibits remarkable flight adaptations, using winds as an energy source to glide for long distances. This is the basis of their foraging strategy, by which they obtain food for themselves and their offspring. Climate change, however, is expected to modify wind patterns over the Southern Ocean. This project will analyze the effect of winds on life history traits (foraging behaviors, body conditions and demographic traits), and the effects of these traits on populations. New demographic models will provide the link between foraging behavior and the physical environment, and evaluate the persistence of this population in the face of climate change.<br/><br/>Understanding and predicting population responses to climate change is important because the world?s climate will continue to change throughout the 21st century and beyond. To help guide conservation strategies and policy decisions in the face of climate change, reliable assessments of population extinction risks are urgently needed. The Black-Browed Albatross is considered endangered by the International Union for Conservation of Nature due to recent drastic reductions in its population size. This project will improve our understanding of the mechanisms by which climate affects the life history and populations of Black-Browed Albatross to improve prediction of extinction risks under future climate change.
The aim of study is to understand how climate-related changes in snow and ice affect predator populations in the Antarctic, using the Adélie penguin as a focal species due to its long history as a Southern Ocean 'sentinel' species and the number of long-term research programs monitoring its abundance, distribution, and breeding biology. Understanding the environmental factors that control predator population dynamics is critically important for projecting the state of populations under future climate change scenarios, and for designing better conservation strategies for the Antarctic ecosystem. For the first time, datasets from a network of observational sites for the Adélie penguin across the entire Antarctic will be combined and analyzed, with a focus on linkages among the ice environment, primary production, and the population responses of Adélie penguins. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. The results of this project can be used to illustrate intuitively to the general public the complex interactions between ice, ocean, pelagic food web and top predators. This project also offers an excellent platform to demonstrate the process of climate-change science - how scientists simulate climate change scenarios and interpret model results. This project supports the training of undergraduate and graduate students in the fields of polar oceanography, plankton and seabird ecology, coupled physical-biological modeling and mathematical ecology. The results will be broadly disseminated to the general oceanographic research community through scientific workshops, conferences and peer-reviewed journal articles, and to undergraduate and graduate education communities, K-12 schools and organizations, and the interested public through web-based servers using existing infrastructure at the investigators' institutions. The key question to be addressed in this project is how climate impacts the timing of periodic biological events (phenology) and how interannual variation in this periodic forcing influences the abundance of penguins in the Antarctic. The focus will be on the timing of ice algae and phytoplankton blooms because the high seasonality of sea ice and associated pulsed primary productivity are major drivers of the Antarctic food web. This study will also examine the responses of Adélie penguins to changes in sea ice dynamics and ice algae-phytoplankton phenology. Adélie penguins, like many other Antarctic seabirds, are long-lived, upper trophic-level predators that integrate the effects of sea ice on the food web at regional scales, and thus serve as a reliable biological indicator of environmental changes. The proposed approach is designed to accommodate the limits of measuring and modeling the intermediate trophic levels between phytoplankton and penguins (e.g., zooplankton and fish) at the pan-Antarctic scale, which are important but latent variables in the Southern Ocean food web. Through the use of remotely sensed and in situ data, along with state of the art statistical approaches (e.g. wavelet analysis) and numerical modeling, this highly interdisciplinary study will advance our understanding of polar ecosystems and improve the projection of future climate change scenarios.
Intellectual Merit: <br/><br/>The PIs propose to establish an ice shelf network of 18 broadband seismographs deployed for two years to obtain high-resolution, mantle-scale images of Earth structure underlying the Ross Sea Embayment. Prior marine geophysical work provides good crustal velocity models for the region seaward of the ice shelf but mantle structure is constrained by only low-resolution images due to the lack of prior seismic deployments. The proposed stations would be established between Ross Island and Marie Byrd Land. These stations would fill a major geological gap within this extensional continental province and would link data sets collected in the Transantarctic Mountain transition/Plateau region (TAMSEIS) and in West Antarctica (POLENET) to improve resolution of mantle features beneath Antarctica. The proposed deployment would allow the PIs to collect seismic data without the expense, logistical complexity, and iceberg hazards associated with ocean bottom seismograph deployments. Tomographic models developed from the proposed data will be used to choose between competing models for the dynamics of the Ross Sea. In particular, the PIs will investigate whether a broad region of hot mantle, including the Eastern Ross Sea, indicates distributed recent tectonic activity, which would call into question models proposing that Eastern Ross extension ceased during the Mesozoic. These data will also allow the PIs to investigate the deeper earth structure to evaluate the possible role of mantle plumes and/or small-scale convection in driving regional volcanism and tectonism across the region.<br/><br/>Broader impacts: <br/><br/>Data from this deployment will be of broad interdisciplinary use. This project will support three graduate and two undergraduate students. At least one student will be an underrepresented minority student. The PIs will interact with the media and include K-12 educators in their fieldwork.
This award supports an integrated field observation, remote sensing and numerical modeling study of the McMurdo Shear Zone (SZ). The SZ is a 5-10 km wide strip of heavily crevassed ice that separates the McMurdo and Ross ice shelves, and is an important region of lateral support for the Ross Ice Shelf. Previous radar and remote sensing studies reveal an enigmatic picture of the SZ in which crevasses detected at depth have no apparent surface expression, and have orientations which are possibly inconsistent with the observed flow field. In the proposed work, we seek to test the hypothesis that the SZ is a zone of chaotic Lagrangian mixing with (intersecting) buried crevasses which leads to rheological instability, potentially allowing large scale velocity discontinuities. The work will involve detailed field-based observations of crevasse distributions and structure using ground-penetrating radar, and GPS and remote sensing observations of the flow and stress field in the SZ. Because of the hazardous nature of the SZ, the radar surveys will be conducted largely with the aid of a lightweight robotic vehicle. Observations will be used to develop a finite element model of ice shelf shear margin behavior. The intellectual merit of this project is an increased understanding of ice shelf shear margin dynamics. Shear margins play a key role in ice shelf stability, and ice shelves in turn modulate the flux of ice from the ice sheet across the grounding line to the ocean. Insights from this project will improve large-scale models being developed to predict ice sheet evolution and future rates of sea level rise, which are topics of enormous societal concern. The broader impacts of the project include an improved basis for US Antarctic Program logistics planning as well as numerous opportunities to engage K-12 students in scientific discovery. Intensified crevassing in the shear zone between the Ross and McMurdo ice shelves would preclude surface crossing by heavy traverse vehicles which would lead to increased costs of delivering fuel to South Pole and a concomitant loss of flight time provided by heavy-lift aircraft for science missions on the continent. Our multidisciplinary research combining glaciology, numerical modeling, and robotics engineering is an engaging way to show how robotics can assist scientists in collecting hazardous field measurements. Our outreach activities will leverage Dartmouth's current NSF GK-12 program, build on faculty-educator relationships established during University of Maine's recent GK-12 program, and incorporate project results into University of Maine's IDEAS initiative, which integrates computational modeling with the existing science curriculum at the middle school level. This award has field work in Antarctica.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The LISSARD project (Lake and Ice Stream Subglacial Access Research Drilling) is one of three research components of the WISSARD integrative initiative (Whillans Ice Stream Subglacial Access Research Drilling) that is being funded by the Antarctic Integrated System Science Program of NSF's Office of Polar Programs, Antarctic Division. The overarching scientific objective of WISSARD is to assess the role of water beneath a West Antarctic ice stream in interlinked glaciological, geological, microbiological, geochemical, and oceanographic systems. The LISSARD component of WISSARD focuses on the role of active subglacial lakes in determining how fast the West Antarctic ice sheet loses mass to the global ocean and influences global sea level changes. The importance of Antarctic subglacial lakes has only been recently recognized, and the lakes have been identified as high priority targets for scientific investigations because of their unknown contributions to ice sheet stability under future global warming scenarios. LISSARD has several primary science goals: A) To provide an observational basis for improving treatments of subglacial hydrological and mechanical processes in models of ice sheet mass balance and stability; B) To reconstruct the past history of ice stream stability by analyzing archives of past basal water and ice flow variability contained in subglacial sediments, porewater, lake water, and basal accreted ice; C) To provide background understanding of subglacial lake environments to benefit RAGES and GBASE (the other two components of the WISSARD project); and D) To synthesize data and concepts developed as part of this project to determine whether subglacial lakes play an important role in (de)stabilizing Antarctic ice sheets. We propose an unprecedented synthesis of approaches to studying ice sheet processes, including: (1) satellite remote sensing, (2) surface geophysics, (3) borehole observations and measurements and, (4) basal and subglacial sampling. <br/><br/>INTELLECTUAL MERIT: The latest report of the Intergovernmental Panel on Climate Change recognized that the greatest uncertainties in assessing future global sea-level change stem from a poor understanding of ice sheet dynamics and ice sheet vulnerability to oceanic and atmospheric warming. Disintegration of the WAIS (West Antarctic Ice Sheet) alone would contribute 3-5 m to global sea-level rise, making WAIS a focus of scientific concern due to its potential susceptibility to internal or ocean-driven instability. The overall WISSARD project will test the overarching hypothesis that active water drainage connects various subglacial environments and exerts major control on ice sheet flow, geochemistry, metabolic and phylogenetic diversity, and biogeochemical transformations. <br/><br/>BROADER IMPACTS: Societal Relevance: Global warming, melting of ice sheets and consequential sea-level rise are of high societal relevance. Science Resource Development: After a 9-year hiatus WISSARD will provide the US-science community with a renewed capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and assets will be accessible for future use through the NSF-OPP drilling contractor. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments (2007). Education and Outreach (E/O): These activities are grouped into four categories: i) increasing student participation in polar research by fully integrating them in our research programs; ii) introducing new investigators to the polar sciences by incorporating promising young investigators in our programs, iii) promotion of K-12 teaching and learning programs by incorporating various teachers and NSTA programs, and iv) reaching a larger public audience through such venues as popular science magazines, museum based activities and videography and documentary films. In summary, WISSARD will promote scientific exploration of Antarctica by conveying to the public the excitement of accessing and studying what may be some of the last unexplored aquatic environments on Earth, and which represent a potential analogue for extraterrestrial life habitats on Europa and Mars.
Conway/1141866<br/><br/>This award supports a project to conduct a suite of experiments to study spatial and temporal variations of basal conditions beneath Beardmore Glacier, an East Antarctic outlet glacier that discharges into the Ross Sea Embayment. The intellectual merit of the project is that it should help verify whether or not global warming will play a much larger role in the future mass balance of ice sheets than previously considered. Recent observations of rapid changes in discharge of fast-flowing outlet glaciers and ice streams suggest that dynamical responses to warming could affect that ice sheets of Greenland and Antarctica. Assessment of possible consequences of these responses is hampered by the lack of information about the basal boundary conditions. The leading hypothesis is that variations in basal conditions exert strong control on the discharge of outlet glaciers. Airborne and surface-based radar measurements of Beardmore Glacier will be made to map the ice thickness and geometry of the sub-glacial trough and active and passive seismic experiments, together with ground-based radar and GPS measurements will be made to map spatial and temporal variations of conditions at the ice-bed interface. The observational data will be used to constrain dynamic models of glacier flow. The models will be used to address the primary controls on the dynamics of Antarctic outlet glaciers, the conditions at the bed, their spatial and temporal variation, and how such variability might affect the sliding and flow of these glaciers. The work will also explore whether or not these outlet glaciers could draw down the interior of East Antarctica, and if so, how fast. The study will take three years including two field seasons to complete and results from the work will be disseminated through public and professional meetings and journal publications. All data and metadata will be made available through the NSIDC web portal. The broader impacts of the work are that it will help elucidate the fundamental physics of outlet glacier dynamics which is needed to improve predictions of the response of ice sheets to changing environmental conditions. The project will also provide support for early career investigators and will provide training and support for one graduate and two undergraduate students. All collaborators are currently involved in scientific outreach and graduate student education and they are committed to fostering diversity.
Ice-core records are critical to understanding past climate variations. An Antarctic ice core currently being drilled at the South Pole will allow detailed investigation of atmospheric gases and fill an important gap in understanding the pattern of climate variability across Antarctica. Critical to the interpretation of any ice core are: 1) accurate chronologies for both the ice and the trapped gas and 2) demonstration that records from the ice core reliably reflect climate. The proposed research will improve the ice and gas chronologies by making measurements of snow compaction in the upstream catchment in order to constrain age models of the ice. These measurements will be a key data set needed for better understanding and predicting time-varying conditions in the upper part of the ice sheet. The research team will measure the modern spatial gradients in accumulation rate, surface temperature, and water stable isotopes from shallow ice cores in the upstream catchment in order to determine the climate history from the ice-core record. The new ice-flow measurements will make it possible to define the path of ice from upstream to the South Pole ice-core drill site to assess spatial gradients in snowfall and to infer histories of snowfall from internal layers within the ice sheet. The project will be led by an early-career scientist, provide broad training to graduate students, and engage in public outreach on polar science.<br/><br/>Ice-core records of stable isotopes, aerosol-born particles, and atmospheric gases are critical to understanding past climate variations. The proposed research will improve the ice and gas chronologies in the South Pole ice core by making in situ measurements of firn compaction in the upstream catchment to constrain models of the gas-age ice-age difference. The firn measurements will be a key data set needed to form a constitutive relationship for firn, and will drive better understanding and prediction of transient firn evolution. The research team will measure the modern gradients in accumulation rate, surface temperature, and water stable isotopes in the upstream catchment to separate spatial (advection) variations from temporal (climate) variations in the ice-core records. The ice-flow measurements will define the flowline upstream of the drill site, assess spatial gradients in accumulation, and infer histories of accumulation from radar-observed internal layers. Results will directly enhance interpretation of South Pole ice-core records, and also advance understanding of firn densification and drive next-generation firn models.
Intellectual Merit:<br/>This project will produce a new compilation of Ross Sea seismic stratigraphy, including new interpretations, that can be used to provide boundary conditions on the tectonic and glacial evolution of West Antarctica and the Ross Sea. The principal goals include compilation of, and interpretation of, all available existing seismic reflection data for the Western Ross Sea, coupled with geophysical modeling to produce paleo-bathymetric reconstructions for the entire 800 km-wide Ross Sea. Specific tasks will include: extending existing work on mapping travel time to reflectors, identifying relations in the seismic data that indicate subsidence through sea level, constructing velocity models for converting travel time to thickness, and using the velocity models to estimate density and porosity of sediments for backstripping analysis. Modeling/backstripping efforts will be used to constrain past bathymetry. Digital interpretations and stratigraphic grids will be provided as supplements to publications. In that way the results of this study can be used in thermal subsidence modeling and restoration of eroded rock to other parts of Ross Embayment and Marie Byrd Land by others. Digital products may be provided in advance of publication to modelers in a way that will not hurt publication chances.<br/><br/>Broader impacts: <br/>The results of this work will be important for paleo-geographic reconstructions of Antarctica and will therefore be of use to a broad range of researchers, particularly those working in the Ross Sea region. The digital products can be used to test models for the past fluctuations of West Antarctic ice sheets, and in planning for future sediment drilling projects. Two undergraduates to be chosen from applicants will be involved in summer internships held at the University of Rhode Island. Outreach will also include a new website and one or more Wikipedia entries related to Ross Sea sub-sea floor characteristics. The project includes an international collaboration with Dr. Chiara Sauli and others at Instituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS) in Italy.
The Palmer Antarctica LTER (Long Term Ecological Research) site has been in operation since 1990. The goal of all the LTER sites is to conduct policy-relevant research on ecological questions that require tens of years of data, and cover large geographical areas. For the Palmer Antarctica LTER, the questions are centered around how the marine ecosystem west of the Antarctica peninsula is responding to a climate that is changing as rapidly as any place on the Earth. For example, satellite observations over the past 35 years indicate the average duration of sea ice cover is now ~90 days (3 months!) shorter than it was. The extended period of open water has implications for many aspects of ecosystem research, with the concurrent decrease of Adèlie penguins within this region regularly cited as an exemplar of climate change impacts in Antarctica. Cutting edge technologies such as autonomous underwater (and possibly airborne) vehicles, seafloor moorings, and numerical modeling, coupled with annual oceanographic cruises, and weekly environmental sampling, enables the Palmer Antarctica LTER to expand and bridge the time and space scales needed to assess climatic impacts. This award includes for the first time study of the roles of whales as major predators in the seasonal sea ice zone ecosystem. The team will also focus on submarine canyons, special regions of enhanced biological activity, along the Western Antarctic Peninsula (WAP).<br/><br/>The current award's overarching research question is: How do seasonality, interannual variability, and long term trends in sea ice extent and duration influence the structure and dynamics of marine ecosystems and biogeochemical cycling? Specific foci within the broad question include: 1. Long-term change and ecosystem transitions. What is the sensitivity or resilience of the ecosystem to external perturbations as a function of the ecosystem state? 2. Lateral connectivity and vertical stratification. What are the effects of lateral transports of freshwater, heat and nutrients on local ocean stratification and productivity and how do they drive changes in the ecosystem? 3. Top-down controls and shifting baselines. How is the ecosystem responding to the cessation of whaling and subsequent long-term recovery of whale stocks? 4. Foodweb structure and biogeochemical processes. How do temporal and spatial variations in foodweb structure influence carbon and nutrient cycling, export, and storage? The broader impacts of the award leverage local educational partnerships including the Sandwich, MA STEM Academy, the New England Aquarium, and the NSF funded Polar Learning and Responding (PoLAR) Climate Change Education Partnership at Columbia's Earth Institute to build new synergies between Arctic and Antarctic, marine and terrestrial scientists and students, governments and NGOs. The Palmer Antarctic LTER will also conduct appropriate cross LTER site comparisons, and serve as a leader in information management to enable knowledge-building within and beyond the Antarctic, oceanographic, and LTER communities.
Ice cores record detailed histories of past climate variations. The South Pole ice core will allow investigation of atmospheric trace gases and fill an important gap in understanding the pattern of climate variability across Antarctica. An accurate timescale that assigns an age to the ice at each depth in the core is essential to interpretation of the ice-core records. This work will use electrical methods to identify volcanic eruptions throughout the past ~40,000 years in the core by detecting the enhanced electrical conductance in those layers due to volcanic impurities in the ice. These eruptions will be pattern-matched to other cores across Antarctica, synchronizing the timing of climate variations among cores and allowing the precise timescales developed for other Antarctic ice cores to be transferred to the South Pole ice core. The well-dated records of volcanic forcing will be combined with records of atmospheric gases, stable water-isotopes, and aerosols to better understand the large natural climate variations of the past 40,000 years. <br/> <br/>The electrical conductance method and dielectric profiling measurements will be made along the length of each section of the South Pole ice core at the National Ice Core Lab. These measurements will help to establish a timescale for the core. Electrical measurements will provide a continuous record of volcanic events for the entire core including through the brittle ice (550-1250m representing ~10,000-20,000 year-old ice) where the core quality and thin annual layers may prevent continuous melt analysis and cause discrete measurements to miss volcanic events. The electrical measurements also produce a 2-D image of the electrical layering on a longitudinal cut surface of each core. These data will be used to identify any irregular or absent layering that would indicate a stratigraphic disturbance in the core. A robust chronology is essential to interpretation of the paleoclimate records from the South Pole ice core. The investigators will engage teachers through talks and webinars with the National Science Teachers Association and will share information with the public at events such as Polar Science Weekend at the Pacific Science Center. Results will be disseminated through publications and conference presentations and the data will be archived and publicly available.
Non-Technical Summary:<br/> About 80 million years ago, the tip of the Antarctic Peninsula in the vicinity of what is now James Ross Island experienced an episode of rapid subsidence, creating a broad depositional basin that collected sediments eroding from the high mountains to the West. This depression accumulated a thick sequence of fossil-rich, organic-rich sediments of the sort that are known to preserve hydrocarbons, and for which Argentina, Chile, and the United Kingdom have overlapping territorial claims. The rocks preserve one of the highest resolution records of the biological and climatic events that led to the eventual death of the dinosaurs at the Cretaceous-Tertiary boundary (about 66 million years ago). A previous collaboration between scientists from the Instituto Antártico Argentino (IAA) and NSF-supported teams from Caltech and the University of Washington were able to show that this mass extinction event started nearly 50,000 years before the sudden impact of an asteroid. The asteroid obviously hit the biosphere hard, but something else knocked it off balance well before the asteroid hit. <br/> A critical component of the previous work was the use of reversals in the polarity of the Earth?s magnetic field as a dating tool ? magnetostratigraphy. This allowed the teams to correlate the pattern of magnetic reversals from Antarctica with elsewhere on the planet. This includes data from a major volcanic eruption (a flood basalt province) that covered much of India 65 million years ago. The magnetic patterns indicate that the Antarctic extinction started with the first pulse of this massive eruption, which was also coincident with a rapid spike in polar temperature. The Argentinian and US collaborative teams will extend this magnetic polarity record back another ~ 20 million years in time, and expand it laterally to provide magnetic reversal time lines across the depositional basin. They hope to recover the end of the Cretaceous Long Normal interval, which is one of the most distinctive events in the history of Earth?s magnetic field. The new data should refine depositional models of the basin, allow better estimates of potential hydrocarbon reserves, and allow biotic events in the Southern hemisphere to be compared more precisely with those elsewhere on Earth. Other potential benefits of this work include exposing several US students and postdoctoral fellows to field based research in Antarctica, expanding the international aspects of this collaborative work via joint IAA/US field deployments, and follow-up laboratory investigations and personnel exchange of the Junior scientists.<br/><br/><br/>Technical Description of Project <br/>The proposed research will extend the stratigraphic record in the late Cretaceous and early Tertiary sediments (~ 83 to 65 Ma before present) of the James Ross Basin, Antarctica, using paleo-magnetic methods. Recent efforts provided new methods to analyze these rocks, yielding their primary magnetization, and producing both magnetic polarity patterns and paleomagnetic pole positions. This provided the first reliable age constraints for the younger sediments on Seymour Island, and quantified the sedimentation rate in this part of the basin. The new data will allow resolution of the stable, remnant magnetization of the sediments from the high deposition rate James Ross basin (Tobin et al., 2012), yielding precise chronology/stratigraphy. This approach will be extended to the re-maining portions of this sedimentary basin, and will allow quantitative estimates for tectonic and sedimentary processes between Cretaceous and Early Tertiary time. The proposed field work will refine the position of several geomagnetic reversals that occurred be-tween the end of the Cretaceous long normal period (Chron 34N, ~ 83 Ma), and the lower portion of Chron 31R (~ 71 Ma). Brandy Bay provides the best locality for calibrating the stratigraphic position of the top of the Cretaceous Long Normal Chron, C34N. Although the top of the Cretaceous long normal Chron is one of the most important correlation horizons in the entire geological timescale, it is not properly correlated to the southern hemisphere biostratigraphy. Locating this event, as well as the other reversals, will be a major addition to understanding of the geological history of the Antarctic Peninsula. These data will also help refine tectonic models for the evolution of the Southern continents, which will be of use across the board for workers in Cretaceous stratigraphy (including those involved in oil exploration).<br/>This research is a collaborative effort with Dr. Edward Olivero of the Centro Austral de Investigaciones Cientificas (CADIC/CONICET) and Prof. Augusto Rapalini of the University of Buenos Aires. The collaboration will include collection of samples on their future field excursions to important targets on and around James Ross Island, supported by the Argentinian Antarctic Program (IAA). Argentinian scientists and students will also be involved in the US Antarctic program deployments, proposed here for the R/V Laurence Gould, and will continue the pattern of joint international publication of the results.
With 70% of the Earth's surface being covered by oceans, a longstanding question of interest to the ecology of migratory seabirds is how they locate their prey across such vast distances. The project seeks to investigate the sensory strategies used in the foraging behavior of procellariiform seabirds, such as petrels, albatrosses and shearwaters. These birds routinely travel over thousands of kilometers of open ocean, apparently using their pronounced olfactory abilities (known to be up to a million times more sensitive than other birds) to identify productive marine areas or locate prey. High resolution tracking, such as provided by miniaturized GPS data loggers (+/- 5m; 10 second sampling), are needed to gain insight into some of the questions as to the sensory mechanisms birds use to locate their prey. Combining these tracking and positioning devices along with stomach temperature recorders capable of indicating prey ingestion, will provide a wealth of new behavioral information. Species specific foraging based on prey specific odors (e.g. krill vs fisheries vs. squid), and mixed strategies using olfaction and visual cues appear to be different for these different marine predators. <br/><br/>Albatrosses are increasingly an endangered species globally, and additional information as to their foraging strategies might lead to better conservation measures such as the avoidance of by-catch by long-line fisheries.<br/>Intimate details of each species foraging activity patterns during the day and night and insight into the conservation of these top predators in pelagic Southern Ocean ecosystems are a few of the research directions these novel fine scale resolution approaches are yielding.
The McMurdo Dry Valleys in Antarctica are recognized as being the driest, coldest and probably one of the harshest environments on Earth. In addition to the lack of water, the biota in the valleys face a very limited supply of nutrients such as nitrogen compounds - necessary for protein synthesis. The glacial streams of the Dry Valleys have extensive cyanobacterial (blue green algae) mats that are a major source of carbon and nitrogen compounds to biota in this region. While cyanobacteria in streams are important as a source of these compounds, other non-photosynthetic bacteria also contribute a significant fraction (~50%) of fixed nitrogen compounds to valley biota. This research effort will involve an examination of exactly which non-phototrophic bacteria are involved in nitrogen fixation and what environmental factors are responsible for controlling nitrogen fixation by these microbes. This work will resolve the environmental factors that control the activity, abundance and diversity of nitrogen-fixing microbes across four of the McMurdo Dry Valleys. This will allow for comparisons among sites of differing latitude, temperature, elevation and exposure to water. These results will be integrated into a landscape wetness model that will help determine the impact of both cyanobacterial and non-photosynthetic nitrogen fixing microorganisms in this very harsh environment.<br/><br/>The Dry Valleys in many ways resemble the Martian environment, and understanding the primitive life and very simple nutrient cycling in the Dry Valleys has relevance for understanding how life might have once existed on other planets. Furthermore, the study of microbes from extreme environments has resulted in numerous biotechnological applications such as the polymerase chain reaction for amplifying DNA and mechanisms for freeze resistance in agricultural crops. Thus, this research should yield insights into how biota survive in extreme environments, and these insights could lead to other commercial applications.
Building on previously funded NSF research, the use of paleobiological and paleogenetic data from mummified elephant seal carcasses found along the Dry Valleys and Victoria Land Coast in areas that today are too cold to support seal colonies (Mirougina leonina; southern elephant seals; SES) supports the former existence of these seals in this region. The occurrence and then subsequent disappearance of these SES colonies is consistent with major shifts in the Holocene climate to much colder conditions at the last ~1000 years BCE). <br/><br/>Further analysis of the preserved remains of three other abundant pinnipeds ? crabeater (Lobodon carciophagus), Weddell (Leptonychotes weddelli) and leopard (Hydrurga leptonyx) will be studied to track changes in their population size (revealed by DNA analysis) and their diet (studied via stable isotope analysis). Combined with known differences in life history, preferred ice habitat and ecosystem sensitivity among these species, this paleoclimate proxy data will be used to assess their exposure and sensitivity to climate change in the Ross Sea region during the past ~1-2,000 years
This CAREER proposal will support an early career female PI to establish an integrated research and education program in the fields of polar biology and environmental microbiology, focusing on single-celled eukaryotes (protists) in high latitude ice-covered Antarctic lakes systems. Protists play important roles in energy flow and material cycling, and act as both primary producers (fixing inorganic carbon by photosynthesis) and consumers (preying on bacteria by phagotrophic digestion). The McMurdo Dry Valleys (MDV) located in Victoria Land, Antarctica, harbor microbial communities which are isolated in the unique aquatic ecosystem of perennially ice-capped lakes. The lakes support exclusively microbial consortia in chemically stratified water columns that are not influenced by seasonal mixing, allochthonous inputs, or direct human impact. This project will exploit permanently stratified biogeochemistry that is unique across the water columns of several MDV lakes to address gaps in our understanding of protist trophic function in aquatic food webs. The proposed research will examine (1) the impact of permanent biogeochemical gradients on protist trophic strategy, (2) the effect of major abiotic drivers (light and nutrients) on the distribution of two key mixotrophic and photoautotrophic protist species, and (3) the effect of episodic nutrient pulses on mixotroph communities in high latitude (ultraoligotrophic) MDV lakes versus low latitude (eutrophic) watersheds. The project will impact the fields of microbial ecology and environmental microbiology by combining results from field, laboratory and in situ incubation studies to synthesize new models for the protist trophic roles in the aquatic food web. The research component of this proposed project will be tightly integrated with the development of two new education activities designed to exploit the inherent excitement associated with polar biological research. The educational objectives are: 1) to establish a teaching module in polar biology in a core undergraduate course for microbiology majors; 2) to develop an instructional module to engage middle school girls in STEM disciplines. Undergraduates and middle school girls will also work with a doctoral student on his experiments in local Ohio watersheds.
This award supports a project to use the Roosevelt Island ice core as a glaciological dipstick for the eastern Ross Sea. Recent attention has focused on the eastern Ross Embayment, where there are no geological constraints on ice thickness changes, due to the lack of protruding rock "dipsticks" where the ice sheet can leave datable records of high stands. Recent work has shown how dated ice cores can be used as dipsticks to derive ice-thickness histories. Partners from New Zealand and Denmark will extract an ice core from Roosevelt Island during the 2010-2011 and 2011-12 austral summers. Their science objective is to contribute to understanding of climate variability over the past 40kyr. The science goal of this project is not the climate record, but rather the history of deglaciation in the Ross Sea. The new history from the eastern Ross Sea will be combined with the glacial histories from the central Ross Sea (Siple Dome and Byrd) and existing and emerging histories from geologic and marine records along the western Ross Sea margin and will allow investigators to establish an updated, self-consistent model of the configuration and thickness of ice in the Ross Embayment during the LGM, and the timing of deglaciation. Results from this work will provide ground truth for new-generation ice-sheet models that incorporate ice streams and fast-flow dynamics. Realistic ice-sheet models are needed not only for predicting the response to future possible environments, but also for investigating past behaviors of ice sheets. This research contributes to the primary goals of the West Antarctic Ice Sheet Initiative as well as the IPY focus on ice-sheet history and dynamics. It also contributes to understanding spatial and temporal patterns of climate change and climate dynamics over the past 40kyr, one of the primary goals of the International Partnerships in Ice Core Sciences (IPICS). The project will help to develop the next generation of scientists and will contribute to the education and training of two Ph.D. students. All participants will benefit from the international collaboration, which will expose them to different field and laboratory techniques and benefit future collaborative work. All participants are involved in scientific outreach and undergraduate education, and are committed to fostering diversity. Outreach will be accomplished through regularly scheduled community and K-12 outreach events, talks and popular writing by the PIs, as well as through University press offices.
Intellectual Merit: <br/>The PI hypothesizes that bedforms found in the Central and Joides troughs can be interpreted as having been formed by rapid retreat, and possible collapse of an ice stream that occupied this area. To test this hypothesis, the PI proposes to conduct a detailed marine geological and geophysical survey of Central and Joides Troughs in the western Ross Sea. This project will bridge gaps between the small and isolated areas previously surveyed and will acquire a detailed sedimentological record of the retreating grounding line. The PI will reconstruct the retreat history of the Central and Joides troughs to century-scale resolution using radiocarbon dating methods and by looking at geomorphic features that are formed at regular time intervals. Existing multibeam, deep tow side-scan sonar, and core data will provide a framework for this research. The western Ross Sea is an ideal study area to investigate a single ice stream and the dynamics controlling its stability, including interactions between both East and West Antarctic Ice Sheets. <br/><br/>Broader impacts: <br/>This proposal includes a post-doc, a graduate and two undergraduate students. The post-doc is involved with teaching an in-service K-12 teacher development and training course at Rice University for high-need teachers with a focus on curriculum enhancement. The project fosters collaboration for the PI and students with researchers at Louisiana State University and international colleagues at the Institute for Paleobiology at the Polish Academy of Sciences. The results from this project could lead to a better understanding of ice sheet and ice stream stability. This project will yield implications for society's understanding of climate change, as this work improves understanding of the behavior of ice sheets and their links to global climate.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The West Antarctic Ice Sheet is believed to be vulnerable to climate change as it is grounded below sea level, is drained by rapidly flowing ice streams and is fringed by floating ice shelves subject to melting by incursions of relatively warm Antarctic circumpolar water. Currently, the most rapidly thinning glaciers in Antarctica occur in the Amundsen and Bellingshausen Sea sectors. This study seeks to place the present day observations into a longer-term geological context over a broad scale by high-resolution swath bathymetric mapping of continental shelf sea floor features that indicate past ice presence and behavior. Gaps in existing survey coverage of glacial lineations and troughs indicating ice flow direction and paleo-grounding zone wedges over the Ross, Amundsen and Bellingshausen Sea sectors are targeted. The surveys will be conducted as part of the 2010 Icebreaker Oden science opportunity and will take advantage of the vessel?s state-of-the-art swath mapping system.<br/><br/>Broader impacts:<br/>This activity will supplement and complement more focused regional studies by US, Swedish, UK, French, Japanese and Polish collaborators also sailing on the Oden. The PI will compile bathymetric data to be acquired by the Oden and other ships in the region over the duration of the project into the existing bathymetric data base. The compiled data set will be made publically available through the NSF founded Antarctic Multibeam Bathymetry and Geophysical Data Synthesis (AMBS) site. It will also be integrated into the GEBCO International Bathymetric Chart of the Southern Ocean (IBCSO) and so significantly improve the basis for ship navigation in the Pacific sector of the Southern Ocean. Undergraduate students will be involved in the research under supervision of the PI via the Lamont summer internship program. The PI is a young investigator and this will be his first NSF grant as a PI.
Intellectual Merit: <br/>The PIs propose to complement the ANDRILL marine record with a terrestrial project that will provide chronological control for past fluctuations of the West Antarctic Ice Sheet (WAIS) and alpine glaciers in McMurdo Sound. The project will develop high-resolution maps of drifts deposited from grounded marine-based ice and alpine glaciers on islands and peninsulas in McMurdo Sound. In addition, the PIs will acquire multi-clast/multi-nuclide cosmogenic analyses of these mapped drift sheets and alpine moraines and use regional climate modeling to shed light on the range of possible environmental conditions in the McMurdo region during periods of grounded ice expansion and recession. The PIs will make use of geological records for ice sheet and alpine glacier fluctuations preserved on the flanks of Mount Discovery, Black Island, and Brown Peninsula. Drifts deposited from grounded, marine-based ice will yield spatial constraints for former advances and retreats of the WAIS. Moraines from alpine glaciers, hypothesized to be of interglacial origin, could yield a first-order record of hydrologic change in the region. Synthesizing the field data, the team proposes to improve the resolution of existing regional-scale climate models for the Ross Embayment. The overall approach and anticipated results will provide the first steps towards linking the marine and terrestrial records in this critical sector of Antarctica.<br/><br/>Broader impacts: <br/>Results from the proposed work will be integrated with outreach programs at Boston University, Columbia University, and Worcester State University. The team will actively collaborate with the American Museum of Natural History to feature this project prominently in museum outreach. The team will also include a PolarTREC teacher as a member of the research team. The geomorphological results will be presented in 3D at Boston University?s Antarctic Digital Image Analyses Lab. The research will form the basis of a PhD dissertation at Boston University.
The McMurdo Dry Valleys (MDV) is a polar desert on the coast of East Antarctica, a region that has not yet experienced climate warming. The McMurdo Dry Valleys Long Term Ecological Research (MCMLTER) project has documented the ecological responses of the glacier, soil, stream and lake ecosystems in the MDV during a cooling trend (from 1986 to 2000) which was associated with the depletion of atmospheric ozone. In the past decade, warming events with strong katabatic winds occurred during two summers and the resulting high streamflows and sediment deposition changed the dry valley landscape, possibly presaging conditions that will occur when the ozone hole recovers. In anticipation of future warming in Antarctica, the overarching hypothesis of the proposed project is: Climate warming in the McMurdo Dry Valley ecosystem will amplify connectivity among landscape units leading to enhanced coupling of nutrient cycles across landscapes, and increased biodiversity and productivity within the ecosystem. Warming in the MDV is hypothesized to act as a slowly developing, long-term press of warmer summers, upon which transient pulse events of high summer flows and strong katabatic winds will be overprinted. Four specific hypotheses address the ways in which pulses of water and wind will influence contemporary and future ecosystem structure, function and connectivity. Because windborne transport of biota is a key aspect of enhanced connectivity from katabatic winds, new monitoring will include high-resolution measurements of aeolian particle flux. Importantly, integrative genomics will be employed to understand the responses of specific organisms to the increased connectivity. The project will also include a novel social science component that will use environmental history to examine interactions between human activity, scientific research, and environmental change in the MDV over the past 100 years. To disseminate this research broadly, MCM scientists will participate in a wide array of outreach efforts ranging from presentations in K-12 classrooms to bringing undergraduates and teachers to the MDV to gain research experience. Planned outreach programs will build upon activities conducted during the International Polar Year (2007-2008), which include development of an interactive DVD for high school students and teachers and publication of a children's book in the LTER Schoolyard Book Series. A teacher's edition of the book with a CD containing lesson plans will be distributed. The project will develop programs for groups traditionally underrepresented in science arenas by publishing some outreach materials in Spanish.
The research will examine how diatoms (an important group of plankton in the Southern Ocean) adapt to environmental change. Diatoms will be sampled from different regions of the Southern Ocean, including the Drake Passage, the Pacific Sector of the Southern Ocean and the Ross Sea and examined to determine the range of genetic variation among diatoms in these regions. Experiments on a range of diatoms will be conducted in home laboratories and will be aimed at measuring shifts in physiological capacities over many generations in response to directional changes in the environment (temperature and pH). The information on the genetic diversity of field populations combined with information on potential rates of adaptability and genome changes will provide insight into ways in which polar marine diatoms populations may respond to environmental changes that may occur in surface oceans in the future or may have occurred during past climate conditions. Such information allows better modeling of biogeochemical cycles in the ocean as well as improves our abilities to interpret records of past ocean conditions. The project will support a doctoral student and a postdoctoral researcher as well as several undergraduate students. These scientists will learn the fundamentals of experimental evolution, a skill set that is being sought in the fields of biology and oceanography. The project also includes a collaboration with the Metcalf Institute for Marine and Environmental Reporting that will design and facilitate a session focused on current research related to evolution and climate change to be held at the annual conference of the National Association of Science Writers (NASW). <br/><br/>Both physiological and genetic variation are key parameters for understanding evolutionary processes in phytoplankton but they are essentially unknown for Southern Ocean diatoms. The extent to which these two factors determine plasticity and adaptability in field populations and the interaction between them will influence how and whether cold-adapted diatoms can respond to changing environments. This project includes a combination of field work to identify genetic diversity within diatoms using molecular approaches and experiments in the lab to assess the range of physiological variation in contemporary populations of diatoms and evolution experiments in the lab to assess how the combination of genetic diversity and physiological variation influence the evolutionary potential of diatoms under a changing environment. This research will uncover general relationships between physiological variation, genetic diversity, and evolutionary potential that may apply across microbial taxa and geographical regions, substantially improving efforts to predict shifts in marine ecosystems. Results from this study can be integrated into developing models that incorporate evolution to predict ecosystem changes under future climate change scenarios.
This project aims to identify which portions of the glacial cover in the Antarctic Peninsula are losing mass to the ocean. This is an important issue to resolve because the Antarctic Peninsula is warming at a faster rate than any other region across the earth. Even though glaciers across the Antarctic Peninsula are small, compared to the continental ice sheet, defining how rapidly they respond to both ocean and atmospheric temperature rise is critical. It is critical because it informs us about the exact mechanisms which regulate ice flow and melting into the ocean. For instance, after the break- up of the Larsen Ice Shelf in 2002 many glaciers began to flow rapidly into the sea. Measuring how much ice was involved is difficult and depends upon accurate estimates of volume and area. One way to increase the accuracy of our estimates is to measure how fast the Earth's crust is rebounding or bouncing back, after the ice has been removed. This rebound effect can be measured with very precise techniques using instruments locked into ice free bedrock surrounding the area of interest. These instruments are monitored by a set of positioning satellites (the Global Positioning System or GPS) in a continuous fashion. Of course the movement of the Earth's bedrock relates not only to the immediate response but also the longer term rate that reflects the long vanished ice masses that once covered the entire Antarctic Peninsula?at the time of the last glaciation. These rebound measurements can, therefore, also tell us about the amount of ice which covered the Antarctic Peninsula thousands of years ago. Glacial isostatic rebound is one of the complicating factors in allowing us to understand how much the larger ice sheets are losing today, something that can be estimated by satellite techniques but only within large errors when the isostatic (rebound) correction is unknown.<br/><br/>The research proposed consists of maintaining a set of six rebound stations until the year 2016, allowing for a longer time series and thus more accurate estimates of immediate elastic and longer term rebound effects. It also involves the establishment of two additional GPS stations that will focus on constraining the "bull's eye" of rebound suggested by measurements over the past two years. In addition, several more geologic data points will be collected that will help to reconstruct the position of the ice sheet margin during its recession from the full ice sheet of the last glacial maximum. These will be based upon the coring of marine sediment sequences now recognized to have been deposited along the margins of retreating ice sheets and outlets. Precise dating of the ice margin along with the new and improved rebound data will help to constrain past ice sheet configurations and refine geophysical models related to the nature of post glacial rebound. Data management will be under the auspices of the UNAVCO polar geophysical network or POLENET and will be publically available at the time of station installation. This project is a small scale extension of the ongoing LARsen Ice Shelf, Antarctica Project (LARISSA), an IPY (International Polar Year)-funded interdisciplinary study aimed at understanding earth system connections related to the Larsen Ice Shelf and the northern Antarctic Peninsula.
Antarctic clouds constitute an important parameter of the surface radiation budget and thus play a significant role in Antarctic climate and climate change. The variability in, and long term trends of, cloud optical and microphysical properties are therefore fundamental in parameterizing the mixed phase (water-snow-ice) coastal Antarctic stratiform clouds experienced around the continent.<br/><br/>Using a spectoradiometer that covers the wavelength range of 350 to 2200nm, the downwelled spectral irradiance at the earth surface (Ross Island) will be used to retrieve the optical depth, thermodynamic phase, liquid water droplet effective radius, and ice-cloud effective particle size of overhead clouds, at hourly intervals and for an austral summer season (Oct-March). Based on the very limited data sets that exist for the maritime Antarctic, expectations are that Ross Island (Lat 78 S) should exhibit clouds with:<br/>a) An abundance of supercooled liquid water, and related mixed-phase cloud processes<br/>b) Cloud nucleation from year round biogenic and oceanic sources, in an otherwise pristine environment<br/>c) Simple cloud geometries of predominantly stratiform cloud decks<br/><br/>Increased understanding of the cloud properties in the region of the main USAP base, McMurdo station is also relevant to operational weather forecasting relevant to aviation. A range of educational and outreach activities are associate with the project, including provision of workshops for high school teachers will be carried out.
Previous studies of the Indo-Pacific region of Antarctica show that the margin of the ice sheet in this region has advanced and retreated into deep interior basins many times in the past. The apparent instability of this region makes it an important target for study in terms of understanding the future of the East Antarctic ice sheet and sea level rise. This project will study a number of processes that control the ice-shelf stability of this region, with the aim of improving projections of the rate and magnitude of future sea-level rise. This project will engage a range of students and train this next generation of scientists in the complex, interdisciplinary issue of ice-ocean interaction. The project will integrate geophysical data collected from aircraft over three critical sections of the East Antarctic grounding line (Totten Glacier, Denman Glacier, and Cook Ice Shelf) with an advanced ocean model. Using Australian and French assets, the team will collect new data around Denman Glacier and Cook Ice Shelf whereas analysis of Totten Glacier will be based on existing data. The project will assess three hypotheses to isolate the processes that drive the differences in observed grounding line thinning among these three glaciers: 1. bathymetry and large-scale ocean forcing control cavity circulation; 2. ice-shelf draft and basal morphology control cavity circulation; 3. subglacial freshwater input across the grounding line controls cavity circulation. The key outcomes of this new project will be to: 1. evaluate of ice-ocean coupling in areas of significant potential sea-level contribution; 2. relate volume changes of grounded and floating ice to regional oceanic heat transport and sub-ice shelf ocean dynamics in areas of significant potential sea-level and meridional overturning circulation impacts; and 3. improve boundary conditions to evaluate mass, heat, and freshwater budgets of East Antarctica's continental margins.
Intellectual Merit: <br/>The MCM-SkyTEM project mapped resistivity in the McMurdo Dry Valleys and at Cape Barne on the Ross Island during the 2011-12 austral season using an airborne transient electromagnetic method. The SkyTEM system is mounted to a helicopter enabling a broad geophysical survey of subsurface resistivity structure over terrain that is inaccessible to traditional ground-based methods. Resistivity measurements obtained distinguish between highly resistive geologic materials such as glacier ice, bedrock and permafrost, and conductive materials such as unfrozen sediments or permafrost with liquid brine to depths of about 300 m. The PIs request funding to derive data products relevant to physical and chemical conditions in potential subsurface microbial habitats of the McMurdo Dry Valleys, similar cold regions on Earth and other planetary bodies. They will use these data products to characterize the hydrologic history of McMurdo Dry Valleys as well as the subsurface hydrologic connectivity in the region to investigate the implications for nutrient and microbial transport. The PIs will make these data products accessible to the research community. <br/><br/>Broader impacts: <br/>Polar microbial habitats are of high societal and scientific interest because they represent important testing grounds for the limits of life on Earth and other planetary bodies. Project deliverables will include teaching aids for undergraduate and graduate students. Two Ph.D. students will obtain advanced research training as part of this project. The PIs and students on this project will also engage in informal public outreach opportunities by presenting at local K-12 schools and reaching out to local media outlets on stories relating to SkyTEM research.
This award provides support for "Investigating (Un)Stable Sliding of Whillans Ice Stream and Subglacial Water Dynamics Using Borehole Seismology: A proposed Component of the Whillans Ice Stream Subglacial Access and Research Drilling" from the Antarctic Integrated Systems Science (AISS) program in the Office of Polar Programs at NSF. The project will use the sounds naturally produced by the ice and subglacial water to understand the glacial dynamics of the Whillans Ice Stream located adjacent to the Ross Ice Shelf in Antarctica.<br/><br/>Intellectual Merit: The transformative component of the project is that in addition to passive surface seismometers, the team will deploy a series of borehole seismometers. Englacial placement of the seismometers has not been done before, but is predicted to provide much better resolution (detection of smaller scale events as well as detection of a much wider range of frequencies) of the subglacial dynamics. In conjunction with the concurrent WISSARD (Whillans Ice Stream Subglacial Access and Research Drilling) project the team will be able to tie subglacial processes to temporal variations in ice stream dynamics and mass balance of the ice stream. The Whillans Ice Stream experiences large changes in ice velocity in response to tidally triggered stick-slip cycles as well as periodic filling and draining of subglacial Lake Whillans. The overall science goals include: improved understanding of basal sliding processes and role of sticky spots, subglacial lake hydrology, and dynamics of small earthquakes and seismic properties of ice and firn.<br/><br/>Broader Impact: Taken together, the research proposed here will provide information on basal controls of fast ice motion which has been recognized by the IPCC as necessary to make reliable predictions of future global sea-level rise. The information collected will therefore have broader implications for global society. The collected information will also be relevant to a better understanding of earthquakes. For outreach the project will work with the overall WISSARD outreach coordinator to deliver information to three audiences: the general public, middle school teachers, and middle school students. The project also provides funding for training of graduate students, and includes a female principal investigator.
The investigators will map glacial deposits and date variations in glacier variability at several ice-free regions in northern Victoria Land, Antarctica. These data will constrain the nature and timing of past ice thickness changes for major glaciers that drain into the northwestern Ross Sea. This is important because during the Last Glacial Maximum (15,000 - 18,000 years ago) these glaciers were most likely flowing together with grounded ice from both the East and West Antarctic Ice Sheets that expanded across the Ross Sea continental shelf to near the present shelf edge. Thus, the thickness of these glaciers was most likely controlled in part by the extent and thickness of the Ross Sea ice sheet and ice shelf. The data the PIs propose to collect can provide constraints on the position of the grounding line in the western Ross Sea during the Last Glacial Maximum, the time that position was reached, and ice thickness changes that occurred after that time. The primary intellectual merit of this project will be to improve understanding of a period of Antarctic ice sheet history that is relatively unconstrained at present and also potentially important in understanding past ice sheet-sea level interactions. <br/><br/>This proposal will support an early career researcher's ongoing program of undergraduate education and research that is building a socio-economically diverse student body with students from backgrounds underrepresented in the geosciences. This proposal will also bring an early career researcher into Antarctic research.
Many key questions in climate research (e.g. relative timing of climate events in different geographic areas, climate-forcing mechanisms, natural threshold levels in the climate system) are dependent on accurate reconstructions of the temporal and spatial distribution of past rapid climate change events in continental, atmospheric, marine and polar realms. This collaborative interdisciplinary research project aims to consolidate, into a single user-friendly database, information about volcanic products detected in Antarctica. By consolidating information about volcanic sources, and physical and geochemical characteristics of volcanic products, this systematic data collection approach will improve the ability of researchers to identify volcanic ash, or tephra, from specific volcanic eruptions that may be spread over large areas in a geologically instantaneous amount of time. Development of this database will assist in the identification and cross-correlation of time intervals in various paleoclimate archives that contain volcanic layers from often unknown sources. The AntT project relies on a cyberinfrastructure framework developed in house through NSF funded CDI-Type I: CiiWork for data assimilation, interpretation and open distribution model. In addition to collection and integration of existing information about volcanic products, this project will focus on filling the information gaps about unique physico-chemical characteristics of very fine (<3 micrometer) volcanic particles (cryptotephra) that are present in Antarctic ice cores. This component of research will involve improving analytical methodology for detecting cryptotephra layers in ice, and will train a new generation of scientists to apply an array of modern state?of?the-art instrumentation available to the project team. <br/><br/>The recognized importance of tephra in establishing a chronological framework for volcanic and sedimentary successions has already resulted in the development of robust regional tephrochronological frameworks (e.g. Europe, Kamchatka, New Zealand, Western North America). The AntT project will provide this framework for Antarctic tephrochronology, as needed for precise correlation records between Antarctic ice cores (e.g. WAIS Divide, RICE, ITASE) and global paleoclimate archives. The results of AntT will be of particular significance to climatologists, paleoclimatologists, atmospheric chemists, geochemists, climate modelers, solar-terrestrial physicists, environmental statisticians, and policy makers for designing solutions to mitigate or cope with likely future impacts of climate change events on modern society.
Intellectual Merit: <br/>This project will use sediment cores from the Victoria Land Basin (VLB), Antarctica, to study secondary (diagenetic) carbonate minerals, as indicators of the basin?s fluid-flow history, within the well-constrained tectonic, depositional, and climatic context provided by sediment cores. This study will provide insights into subsurface processes in Victoria Land Basin, Antarctica and their relationships with the region?s climatic, cryospheric, and tectonic history. The work will utilize cores previously recovered by US-sponsored stratigraphic drilling projects (CIROS, CRP, and ANDRILL projects). This work is motivated by the unexpected discovery of dense brine in the subsurface of Southern McMurdo Sound during drilling by the ANDRILL Southern McMurdo Sound project. The presence of the brine is intriguing because it contradicts previous models for the origin of subsurface fluids that called upon large contributions from glacial melt water. Project objectives involve documenting the distribution of the brine (and potentially other fluids) via characterization of diagenetic precipitates. The approach will involve integration of petrographic and geochemical data (including conventional carbon, oxygen, and ?clumped? isotopes) to fully characterize diagenetic phases and allow development of a robust paragenetic history. This work will provide novel insights into the Cenozoic evolution of the VLB and, more broadly, the role of glacial processes in generating subsurface fluids. <br/><br/>Broader impacts: <br/>Results from this project will help understand the origins of brines, groundwater and hydrocarbon reservoirs in analogous modern and ancient deposits elsewhere, which is of broad interest. This project will support the training of one graduate and one undergraduate student at the University of Nebraska-Lincoln (UNL) providing learning opportunities in sedimentary geology and diagenesis, fields with wide applicability. This proposal emphasizes rapid dissemination of results to the scientific community via conference presentations and contributions to peer-reviewed publications. The results will be integrated into education activities designed to develop skills in petrography and diagenesis, which are highly sought after in the energy sector. The project will generate a well-constrained dataset that allows direct linkage of diagenetic phases to environmental and tectonic change across a large sedimentary basin which will provide the basis for a comprehensive case study in an upper-level course (Sedimentary Petrography and Diagenesis) at UNL. In addition, online exercises will be developed and submitted to an open-access site (SEPM Stratigraphy Web) dedicated to sedimentary geology.
Intellectual Merit: <br/>The PIs propose to investigate last glacial maximum through Holocene glacial change on the northeastern Antarctic Peninsula, an area distinguished by dramatic ice shelf collapses and retreat of upstream glaciers. However, there is a lack of long-term context to know the relative significance of recent events over longer time scales. The PIs will obtain data on former ice margin positions, ice thicknesses, glacier retreat and thinning rates, and Holocene glacier change in the James Ross Island Archipelago and areas near the former Larsen-A ice shelf. These data include maximum- and minimum-limiting 14C and cosmogenic-nuclide exposure dates integrated with geomorphology and stratigraphy. Understanding the extent, nature, and history of glacial events is important for placing current changes in glacial extent into a long-term context. This research will also contribute to understanding the sensitivity of ice shelves and glaciers in this region to climate change. Records of changes in land-terminating glaciers will also address outstanding questions related to climate change since the LGM and through the Holocene. The PIs will collect samples during cooperative field projects with scientists of the Instituto Antártico Argentino and the Korea Polar Research Institute planned as part of existing, larger, research projects.<br/><br/>Broader impacts: <br/>The proposed work includes collaborations with Argentina and Korea. The PIs are currently involved in or are initiating education and outreach activities that will be incorporated into this project. These include interactions with the American Museum of Natural History, the United States Military Academy at West Point, and undergraduate involvement in their laboratories. This project provides a significant opportunity to engage the public as it focuses on an area where environmental changes are the object of attention in the popular media.
Ocean acidification and increased temperatures are projected to be the primary impacts of global climate change on polar marine ecosystems over the next century. While recent research has focused on the effects of these drivers on calcifying organisms, less is known about how these changes may affect vertebrates. This research will focus on two Antarctic fishes, Trematomus bernacchii and Pagothenia borchgrevinki. Fish eggs and larvae will be collected in McMurdo Sound and reared under different temperature and pH regimes. Modern techniques will be used to examine subsequent changes in physiology, growth, development and gene expression over both short and long timescales. The results will fill a missing gap in our knowledge about the response of non-calcifying organisms to projected changes in pH and temperature. Results will be widely disseminated through publications as well as through presentations at national and international meetings; raw data will also be made available through open-access, web-based databases. This project will support the research and training of three graduate and three undergraduate students. As well, this project will foster the development of two modules on climate change and ocean acidification for an Introduction to Biology course.
Intellectual Merit: <br/>This project will determine the potential vulnerability of key ice streams to incursions of warmer ocean water onto the continental shelf and if this mechanism could already explain any of the observed thinning of the ice sheet. It will provide important constrains on ice dynamic of the investigated section of the EAIS, and thus will be critical for future ice sheet models and provide mechanisms for EAIS contributions to past sea level high-stand. The PI proposes to investigate four key ice stream systems on the continental shelf between ~90°E and 160°E. They will use multibeam bathymetry to identify if and where cross-shelf troughs exist to help determine whether these troughs could provide potential pathways for warmer ocean water. Furthermore, detailed analysis of morphological features of these troughs could provide information on past ice dynamic, maximum extent, and flow direction of related paleo ice streams. The PIs will also conduct water column measurements along these troughs and on the continental slope to determine whether warmer ocean water could enter the shelf in the near future, or if such water has already entered any troughs, and thus might be causing the observed thinning of some ice streams.<br/><br/>Broader impacts: <br/>This project includes the participation and support of undergraduate and graduate students in field work and data analysis. The possible involvement of a PolarTREC teacher and the Earth2Class teachers program will reach out to K-12 students.
Intellectual Merit: <br/>The role that Antarctica has played in vertebrate evolution and paleobiogeography during the Late Cretaceous and early Paleogene is largely unknown. Evidence indicates that Antarctica was home to a diverse flora during the Late Cretaceous and Paleogene, yet the vertebrates that must have existed on the continent remain virtually unknown. To fill this gap, the PIs have formed the Antarctic Vertebrate Paleontology Initiative (AVPI), whose goal is to search for and collect Late Cretaceous-Paleogene vertebrate fossils in Antarctica at localities that have never been properly surveyed, as well as in areas of proven potential. Two field seasons are proposed for the James Ross Island Group on the northeastern margin of the Antarctic Peninsula. Expected finds include chondrichthyan and osteichthyan fishes, marine reptiles, ornithischian and non-avian theropod dinosaurs, ornithurine birds, and therian and non-therian mammals. Hypotheses to be tested include: 1) multiple extant bird and/or therian mammal lineages originated during the Cretaceous and survived the K-Pg boundary extinction event; 2) the "Scotia Portal" permitted the dispersal of continental vertebrates between Antarctica and South America prior to the latest Cretaceous and through to the late Paleocene or early Eocene; 3) Late Cretaceous non-avian dinosaurs from Antarctica are closely related to coeval taxa from other Gondwanan landmasses; 4) terminal Cretaceous marine reptile faunas from southern Gondwana differed from contemporaneous but more northerly assemblages; and 5) the collapse of Antarctic ichthyofaunal diversity during the K-Pg transition was triggered by a catastrophic extinction.<br/><br/>Broader impacts: <br/>The PIs will communicate discoveries to audiences through a variety of channels, such as the Dinosaurs in Their Time exhibition at Carnegie Museum of Natural History and the outreach programs of the Environmental Science Institute of the University of Texas at Austin. In addition, Carnegie Museum will launch a student-oriented programming initiative using AVPI research as a primary focus. This array of activities will help some 2,000 Pittsburgh-area undergraduates to explore the relevance of deep-time discoveries to critical modern issues. The AVPI will provide research opportunities for eight undergraduate and three graduate students, several of whom will receive field training in Antarctica. Fossils will be accessioned into the Carnegie Museum collection, and made accessible virtually through the NSF-funded Digital Morphology library at University of Texas.
Intellectual Merit: <br/>To understand Antarctica's geodynamic development, origin of the Transantarctic Mountains (TAMs) and the Wilkes Subglacial Basin (WSB) must be determined. Current constraints on the crustal thickness and seismic velocity structure beneath the TAMs and the WSB are limited, leading to uncertainties over competing geologic models that have been suggested to explain their formation. The PI proposes to broaden the investigation of this region with a new seismic deployment, the Transantarctic Mountains Northern Network (TAMNNET), a 15-station array across the northern TAMs and the WSB that will fill a major gap in seismic coverage. Data from TAMNNET will be combined with that from other previous and ongoing seismic initiatives and will be analyzed using proven modeling techniques to generate a detailed image of the seismic structure beneath the TAMs and the WSB. These data will be used to test three fundamental hypotheses: the TAMs are underlain by thickened crust, the WSB is characterized by thin crust and thick sedimentary layers, and slow seismic velocities are prevalent along strike beneath the TAMs. Results from the proposed study will provide new information about the nature and formation of the Antarctic continent and will help to advance our understanding of important global processes, such as mountain building and basin formation. The proposed research also has important implications for other fields of Antarctic science. Constraints on the origin of the TAMs uplift are critical for climate and ice sheet models, and new information acquired about variations in the thermal and lithospheric structure beneath the TAMs and the WSB will be used to estimate critical ice sheet boundary conditions. <br/><br/>Broader impacts: <br/>This project incorporates three educational strategies to promote the integration of teaching and research. Graduate students will be trained in Antarctic tectonics and seismic processing through hands-on fieldwork and data analysis techniques. Through NSF's PolarTREC program, the PI will work with K-12 educators. The PI will develop a three-week summer field program for recent high school graduates and early-career undergraduate students from Minority-Serving Institutions in Alabama. Teaching materials and participant experiences will be shared with individuals outside the program via a course website. Following the summer program, participants who were particularly engaged will be offered internship opportunities to analyze TAMNNET data. In successive years, the students could assist with fieldwork and could be recruited into the graduate program under the PI's supervision. Ultimately, this program would not only serve to educate undergraduates but would also generate a pipeline of underrepresented students into the geosciences.
The Weddell seal is a champion diving mammal. The physiology that permits these animals to sustain extended breath-hold periods and survive the extreme pressure of diving deep allows them to thrive in icy Antarctic waters. Key elements of their physiological specializations to breath-hold diving are their ability for remarkable adjustment of their heart and blood vessel system, coordinating blood pressure and flow to specific body regions based on their metabolic requirements, and their ability to sustain periods without oxygen. Identifying the details of these strategies has tremendous potential to better inform human medicine, helping us to develop novel therapies for cardiovascular trauma (e.g. stroke, heart attack) and diseases associated with blunted oxygen delivery to tissues (e.g. pneumonia, sepsis, or cancer). The goal of this project is to document specific genes that control these cardiovascular adjustments in seals, and to compare their abundance and activity with humans. Specifically, the investigators will study a signaling pathway that coordinates local blood flow. They will also use tissue samples to generate cultured cells from Weddell seals that can be used to study the molecular effects of low oxygen conditions in the laboratory. The project will further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. The project will train a pre-veterinary student researcher will conduct public outreach via a center for community health improvement, a multicultural affairs office, and a public aquarium. The goal of this study is to unravel the molecular mechanisms underlying the dive response. A hallmark of the dive response is tissue-specific vascular system regulation, likely resulting from variation in both nerve inputs and in production of local signaling molecules produced by blood vessel cells. The investigators will use emerging genomic information to begin to unravel the genetics underlying redistribution of the circulation during diving. They will also directly test the hypothesis that modifications in the signaling system prevent local blood vessel changes under low oxygen conditions, thereby allowing the centrally mediated diving reflex to override local physiological responses and to control the constriction of blood vessel walls in Weddell seals. They will perform RNA-sequencing of Weddell seal tissues and use the resulting sequence, along with information from other mammals such as dog, to obtain a full annotation (identifying all genes based on named features of reference genomes) of the existing genome assembly for the Weddell seal, facilitating comparative and species-specific genomic research. They will also generate a Weddell seal pluripotent stem cell line which should be a valuable research tool for cell biologists, molecular biologists and physiologists that will allow them to further test their hypotheses. It is expected that the proposed studies will advance our knowledge of the biochemical and physiological adaptations that allow the Weddell seal to thrive in the Antarctic environment.
Marine mammals that inhabit high latitude environments have evolved unique mechanisms to execute a suite of energetically-costly life history events (CLHEs) within a relatively short timeframe when conditions are most favorable. Understanding the intrinsic and extrinsic factors that regulate CLHEs is particularly important in species such as Weddell seals, as both reproduction and molt are associated with large reductions in foraging effort, and the timing and outcome of each appears linked with the other. The long-term mark recapture program on Erebus Bay's Weddell seals provides a unique opportunity to examine CLHEs in a known-history population. The proposed work will monitor physiological condition, pregnancy status, and behavior at various times throughout the year to determine if molt timing is influenced by prior reproductive outcome, and if it, in turn, influences future reproductive success. These data will then be used to address the demographic consequences of trade-offs between CLHEs in Weddell seals. The impact of environmental conditions and CLHE timing on population health will also be modeled so that results can be extended to other climates and species. <br/><br/>An improved understanding of the interactions between CLHEs and the environment is important in predicting the response of organisms from higher trophic levels to climate change. Results will be widely disseminated through publications as well as through presentations at national and international meetings. In addition, raw data will be made available through open-access databases. This project will support the research and training of graduate students and a post-doctoral researcher and will further foster an extensive public outreach collaboration.
Intellectual Merit: <br/>Noble gases in groundwater systems can indicate past climates in ice-free regions through estimation of noble gas temperatures. Traditional noble gas temperatures cannot be derived in ice-covered regions where water is not in contact with the atmosphere. The goal of the proposed work is to take advantage of noble gas properties in ice covered lakes at the ice/water interface to develop a new paleoclimate proxy with the potential to be routinely used in both polar and alpine glacial regions. The evolution of the Taylor Valley lakes is intimately connected to the dynamics of nearby glaciers, as well as the advance and retreat of the Ross Ice Shelf, both of which are dictated by climate change. The perennial ice cover of the lakes form at the water/ice interface and sublimate at the top rendering these lakes ideal to test and develop this new proxy. The proposed research involves conducting an extensive noble gas sampling campaign of lake water, stream water, ice covers and glacial ice. This data set, together with data continuously collected in the area will provide a solid basis to develop, test and refine mathematical models capable of accurately describing heavy noble gas concentration profiles as well as their overall inventory in the lakes over time. These will provide information on the occurrence of major climatic events while simultaneously providing temporal constraints on such events. <br/><br/>Broader impacts: <br/>The findings of this work will be inserted into a new class that the PI has created at the University of Michigan targeted at non-science majors. It will create research opportunities for 1-2 undergraduates each year and will support a PhD student. The outcomes of this research could have strong societal relevance.
Intellectual Merit: <br/>The PIs propose to address the question of whether ice surface melting zones developed at high elevations during warm climatic phases in the Transantarctic Mountains. Evidence from sediment cores drilled by the ANDRILL program indicates that open water in the Ross Sea could have been a source of warmth during Pliocene and Pleistocene. The question is whether marine warmth penetrated inland to the ice sheet margins. The glacial record may be ill suited to answer this question, as cold-based glaciers may respond too slowly to register brief warmth. Questions also surround possible orbital controls on regional climate and ice sheet margins. Northern Hemisphere insolation at obliquity and precession timescales is thought to control Antarctic climate through oceanic or atmospheric connections, but new thinking suggests that the duration of Southern Hemisphere summer may be more important. The PIs propose to use high elevation alluvial deposits in the Transantarctic Mountains as a proxy for inland warmth. These relatively young fans, channels, and debris flow levees stand out as visible evidence for the presence of melt water in an otherwise ancient, frozen landscape. Based on initial analyses of an alluvial fan in the Olympus Range, these deposits are sensitive recorders of rare melt events that occur at orbital timescales. For their study they will 1) map alluvial deposits using aerial photography, satellite imagery and GPS assisted field surveys to establish water sources and to quantify parameters effecting melt water production, 2) date stratigraphic sequences within these deposits using OSL, cosmogenic nuclide, and interbedded volcanic ash chronologies, 3) use paired nuclide analyses to estimate exposure and burial times, and rates of deposition and erosion, and 4) use micro and regional scale climate modeling to estimate paleoenvironmental conditions associated with melt events.<br/><br/>Broader impacts: <br/>This study will produce a record of inland melting from sites adjacent to ice sheet margins to help determine controls on regional climate along margins of the East Antarctic Ice Sheet to aid ice sheet and sea level modeling studies. The proposal will support several graduate and undergraduates. A PhD student will be supported on existing funding. The PIs will work with multiple K 12 schools to conduct interviews and webcasts from Antarctica and they will make follow up visits to classrooms after the field season is complete.
1043517/Clark<br/><br/>This award supports a project to develop a better understanding of the response of the WAIS to climate change. The timing of the last deglaciation of the western Ross Sea will be improved using in situ terrestrial cosmogenic nuclides (3He, 10Be, 14C, 26Al, 36Cl) to date glacial erratics at key areas and elevations along the western Ross Sea coast. A state-of-the art ice sheet-shelf model will be used to identify mechanisms of deglaciation of the Ross Sea sector of WAIS. The model results and forcing will be compared with observations including the new cosmogenic data proposed here, with the aim of better determining and understanding the history and causes of WAIS deglaciation in the Ross Sea. There is considerable uncertainty, however, in the history of grounding line retreat from its last glacial maximum position, and virtually nothing is known about the timing of ice- surface lowering prior to ~10,000 years ago. Given these uncertainties, we are currently unable to assess one of the most important questions regarding the last deglaciation of the global ice sheets, namely as to whether the Ross Sea sector of WAIS contributed significantly to meltwater pulse 1A (MWP-1A), an extraordinarily rapid (~500-year duration) episode of ~20 m sea-level rise that occurred ~14,500 years ago. The intellectual merit of this project is that recent observations of startling changes at the margins of the Greenland and Antarctic ice sheets indicate that dynamic responses to warming may play a much greater role in the future mass balance of ice sheets than considered in current numerical projections of sea level rise. The broader impacts of this work are that it has direct societal relevance to developing an improved understanding of the response of the West Antarctic ice sheet to current and possible future environmental changes including the sea-level response to glacier and ice sheet melting due to global warming. The PI will communicate results from this project to a variety of audiences through the publication of peer-reviewed papers and by giving talks to public audiences. Finally the project will support a graduate student and undergraduate students in all phases of field-work, laboratory work and data interpretation.
The research supported in this project will examine the effects of environmental change on a key Antarctic marine invertebrate, a pelagic mollusk, the pteropod, Limacina helicina antarctica. There are two main activities in this project: (1) to deploy oceanographic equipment ? in this case, autonomously recording pH sensors called SeaFETs and other devices that record temperature and salinity, and (2) to use these environmental data in the laboratory at McMurdo Station to study the response of the marine invertebrates to future changes in water quality that is expected in the next few decades. Notably, changes in oceanic pH (aka ocean acidification) and ocean warming are projected to be particularly threatening to calcifying marine organisms in cold-water, high latitude seas, making tolerance data on these organisms a critical research need in Antarctic marine ecosystems. <br/><br/>These Antarctic shelled-animals are especially vulnerable to dissolution stress from ocean acidification because they currently inhabit seawater that is barely at the saturation level to support biogenic calcification. Indeed, these polar animals are considered to be the 'first responders' to chemical changes in the surface oceans. Thus, this project will lead to information about the adaptive capacity of L. helcina antarctica. From an ecological perspective this is important because this animal is a critical part of the Antarctic food chain in coastal waters and changes in its abundance will impact other species. Finally, the research conducted in this project will serve as a training and educational opportunity for undergraduate and graduate students as well as postdoctoral scholars.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Mount Erebus is Antarctica?s most active volcano that has been in a persistent state of activity for at least the last 35 years. It has a unique geochemistry among the Earth's active volcanoes and is also unique in hosting a persistent convecting lake(s) of anorthclase phonolite magma in its summit crater. The relative simplicity of the magmatic system, consistency of activity, and accessibility of close-range observation make Erebus attractive as a target for extensive studies. Although the Erebus' seismicity and eruptive activity and processes are becoming increasingly well understood over years of research, there is a near total lack of understanding its deeper magmatic system. The primary goal of this proposal is to continue supporting the Mt. Erebus Volcano Observatory (MEVO III) improving our current understanding of the Erebus eruptive and non-eruptive magmatic system using an integrated approach from geophysical, geochemical and remote sensing observations. This goal can be grouped into the following fundamental research objectives: (a) to sustain year-round surveillance of on-going volcanic activity primarily using geophysical observatories; (b) to understand processes within the convecting conduit which feeds the persistent lava lakes; and (c) to understand the impact of Erebus eruptive activity upon the Antarctic environment. Continued reliance on students provides a broader impact to this proposed research and firmly grounds this effort in its educational mission.
Antarctic benthic communities are characterized by many species of sponges (Phylum Porifera), long thought to exhibit extremely slow demographic patterns of settlement, growth and reproduction. This project will analyze many hundreds of diver and remotely operated underwater vehicle photographs documenting a unique, episodic settlement event that occurred between 2000 and 2010 in McMurdo Sound that challenges this paradigm of slow growth. Artificial structures were placed on the seafloor between 1967 and 1974 at several sites, but no sponges were observed to settle on these structures until 2004. By 2010 some 40 species of sponges had settled and grown to be surprisingly large. Given the paradigm of slow settlement and growth supported by the long observation period (37 years, 1967-2004), this extraordinary large-scale settlement and rapid growth over just a 6-year time span is astonishing. This project utilizes image processing software (ImageJ) to obtain metrics (linear dimensions to estimate size, frequency, percent cover) for sponges and other fauna visible in the photographs. It uses R to conduct multidimensional scaling to ordinate community data and ANOSIM to test for differences of community data among sites and times and structures. It will also use SIMPER and ranked species abundances to discriminate species responsible for any differences. <br/><br/>This work focuses on Antarctic sponges, but the observations of massive episodic recruitment and growth are important to understanding seafloor communities worldwide. Ecosystems are composed of populations, and populations are ecologically described by their distribution and abundance. A little appreciated fact is that sponges often dominate marine communities, but because sponges are so hard to study, most workers focus on other groups such as corals, kelps, or bivalves. Because most sponges settle and grow slowly their life history is virtually unstudied. The assumption of relative stasis of the Antarctic seafloor community is common, and this project will shatter this paradigm by documenting a dramatic episodic event. Finally, the project takes advantage of old transects from the 1960s and 1970s and compares them with extensive 2010 surveys of the same habitats and sometimes the same intact transect lines, offering a long-term perspective of community change. The investigators will publish these results in peer-reviewed journals, give presentations to the general public and will involve students from local outreach programs, high schools, and undergraduates at UCSD to help with the analysis.
The role that Antarctica has played in vertebrate evolution and paleobiogeography during the Late Cretaceous and early Paleogene is largely unknown. Evidence indicates that Antarctica was home to a diverse flora during the Late Cretaceous and Paleogene, yet the vertebrates that must have existed on the continent remain virtually unknown. To fill this gap, the PIs have formed the Antarctic Vertebrate Paleontology Initiative (AVPI), whose goal is to search for and collect Late Cretaceous-Paleogene vertebrate fossils in Antarctica at localities that have never been properly surveyed, as well as in areas of proven potential. Two field seasons are proposed for the James Ross Island Group on the northeastern margin of the Antarctic Peninsula. Expected finds include chondrichthyan and osteichthyan fishes, marine reptiles, ornithischian and non-avian theropod dinosaurs, ornithurine birds, and therian and non-therian mammals. Hypotheses to be tested include: 1) multiple extant bird and/or therian mammal lineages originated during the Cretaceous and survived the K-Pg boundary extinction event; 2) the ?Scotia Portal? permitted the dispersal of continental vertebrates between Antarctica and South America prior to the latest Cretaceous and through to the late Paleocene or early Eocene; 3) Late Cretaceous non-avian dinosaurs from Antarctica are closely related to coeval taxa from other Gondwanan landmasses; 4) terminal Cretaceous marine reptile faunas from southern Gondwana differed from contemporaneous but more northerly assemblages; and 5) the collapse of Antarctic ichthyofaunal diversity during the K-Pg transition was triggered by a catastrophic extinction.<br/><br/>Broader impacts: <br/>The PIs will communicate discoveries to audiences through a variety of channels, such as the Dinosaurs in Their Time exhibition at Carnegie Museum of Natural History and the outreach programs of the Environmental Science Institute of the University of Texas at Austin. In addition, Carnegie Museum will launch a student-oriented programming initiative using AVPI research as a primary focus. This array of activities will help some 2,000 Pittsburgh-area undergraduates to explore the relevance of deep-time discoveries to critical modern issues. The AVPI will provide research opportunities for eight undergraduate and three graduate students, several of whom will receive field training in Antarctica. Fossils will be accessioned into the Carnegie Museum collection, and made accessible virtually through the NSF-funded Digital Morphology library at University of Texas.
Severinghaus/0839031 <br/><br/>This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>This award supports a project to develop a precise gas-based chronology for an archive of large-volume samples of the ancient atmosphere, which would enable ultra-trace gas measurements that are currently precluded by sample size limitations of ice cores. The intellectual merit of the proposed work is that it will provide a critical test of the "clathrate hypothesis" that methane clathrates contributed to the two abrupt atmospheric methane concentration increases during the last deglaciation 15 and 11 kyr ago. This approach employs large volumes of ice (>1 ton) to measure carbon-14 on past atmospheric methane across the abrupt events. Carbon-14 is an ideal discriminator of fossil sources of methane to the atmosphere, because most methane sources (e.g., wetlands, termites, biomass burning) are rich in carbon-14, whereas clathrates and other fossil sources are devoid of carbon-14. The proposed work is a logical extension to Taylor Glacier, Antarctica, of an approach pioneered at the margin of the Greenland ice sheet over the past 7 years. The Greenland work found higher-than-expected carbon-14 values, likely due in part to contaminants stemming from the high impurity content of Greenland ice and the interaction of the ice with sediments from the glacier bed. The data also pointed to the possibility of a previously unknown process, in-situ cosmogenic production of carbon-14 methane (radiomethane) in the ice matrix. Antarctic ice in Taylor Glacier is orders of magnitude cleaner than the ice at the Greenland site, and is much colder and less stratigraphically disturbed, offering the potential for a clear resolution of this puzzle and a definitive test of the cosmogenic radiomethane hypothesis. Even if cosmogenic radiomethane in ice is found, it still may be possible to reconstruct atmospheric radiomethane with a correction enabled by a detailed understanding of the process, which will be sought by co-measuring carbon-14 in carbon monoxide and carbon dioxide. The broader impacts of the proposed work are that the clathrate test may shed light on the stability of the clathrate reservoir and its potential for climate feedbacks under human-induced warming. Development of Taylor Glacier as a "horizontal ice core" would provide a community resource for other researchers. Education of one postdoc, one graduate student, and one undergraduate, would add to human resources. This award has field work in Antarctica.
A range of chemical and microphysical pathways in polar latitudes, including spring time (tropospheric) ozone depletion, oxidative pathways for mercury, and cloud condensation nuclei (CCN) production leading to changes in the cloud cover and attendant surface energy budgets, have been invoked as being dependent upon the emission of halogen gases formed in sea-ice. <br/><br/>The prospects for climate warming induced reductions in sea ice extent causing alteration of these incompletely known surface-atmospheric feedbacks and interactions requires confirmation of mechanistic details in both laboratory studies and field campaigns. One such mechanistic question is how bromine (BrO and Br) enriched snow migrates or is formed through processes in sea-ice, prior to its subsequent mobilization as an aerosol fraction into the atmosphere by strong winds. Once aloft, it may react with ozone and other atmospheric species. Dartmouth researchers will collect snow from the surface of sea ice, from freely blowing snow and in sea-ice cores from Cape Byrd, Ross Sea. A range of spectroscopic, microanalytic and and microstructural approaches will be subsequently used to determine the Br distribution gradients through sea-ice, in order to shed light on how sea-ice first forms and then releases bromine species into the polar atmospheric boundary layer.
Intellectual Merit: <br/>Magmas generated during subduction of oceanic lithosphere beneath active continental margins typically have a calc-alkaline chemistry. However, igneous rocks with signatures usually associated with anorogenic magmatism are increasingly being found with calc-alkaline rocks in subduction zones. These enigmatic rocks provide insight into a variety of magmatic and structural processes that are fundamental to subduction zone dynamics but processes that lead to their petrogenesis remain a matter of debate. This project will investigate the Koettlitz Glacier Alkaline Province (KGAP) in the Transantarctic Mountains, which is a section through a Na-alkaline province bounded to the north and south by calc-alkaline magmatism. This province potentially contains key information on the thermo-mechanical processes leading to generation of Na-alkaline rocks in subduction systems. The PI will examine structures that bound the KGAP as well as intrusives and metasedimentary rocks contained within it to determine the tectonomagmatic history in the framework of two end-member hypotheses: the KGAP represents a crustal-scale extensional or transtensional domain in a subduction setting; or the KGAP formed in response to ridge subduction. <br/><br/>Broader impacts: <br/>This study will train three graduate and three undergraduate students incorporating hands-on experience with state of the art instrumentation. Each summer, four high school students will be incorporated into various aspects of the laboratory-based research through the UCSB research mentorship program. This project will stimulate refinement of in-situ LA-ICPMS methods and development of collaborative linkages with Antarctic geologists at GNS Science in New Zealand. Results will be disseminated via papers and presentations at international conferences.
1043649/Braun<br/><br/><br/>This award supports a project to determine the current mass balance of selected glaciers of the Western Antarctic Peninsula (WAP) and adjacent islands, including King George Island and Livingston Island. A major goal is to discriminate the climatic and dynamic components of the current mass budget. The dynamic component will be assessed using a flux gate approach. Glacier velocity fields will be derived by offset tracking on repeat SAR satellite imagery, and ice thicknesses across grounding lines or near terminus will be approximated from a new methods based on mass continuity. The surface mass balance will be computed from a spatially distributed temperature-index mass-balance model forced by temperature and precipitation data from regional climate models. Our results will provide improved mass budget estimates of Western Antarctic Peninsula glaciers and a more thorough understanding of the ratio between the climatic and dynamic components. The techniques to be developed will be applicable to other glaciers in the region allowing regional scale mass budgets to be derived. The broader impacts of this work are that glacier wastage is currently the most important contributor to global sea level rise and the Antarctic Peninsula has been identified as one of the largest single contributors. Future sea-level rise has major societal, economic and ecological implications. The activity will foster new partnerships through collaboration with European and South American colleagues. The project will form the base of of a postdoctoral research fellowship. It will also provide training of undergraduate and graduate students through inclusion of data and results in course curriculums.
Abstract<br/><br/>The Erebus Bay population of Weddell seals in Antarctica?s Ross Sea is the most southerly breeding population of mammal in the world, closely associated with persistent shore-fast ice, and one that has been intensively studied since 1968. The resulting long-term database, which includes data for 20,586 marked individuals, contains detailed population information that provides an excellent opportunity to study linkages between environmental conditions and demographic processes in the Antarctic. The population?s location is of special interest as the Ross Sea is one of the most productive areas of the Southern Ocean, one of the few pristine marine environments remaining on the planet, and, in contrast to the Antarctic Peninsula and Arctic, is undergoing a gradual lengthening of the sea-ice season.<br/>The work to be continued here capitalizes on (1) long-term data for individual seals and their polar environment; (2) experience collecting and analyzing data from the extensive study population; and (3) recent statistical advances in hierarchical modeling that allow for rigorous treatment of individual heterogeneity (in mark-recapture and body mass data) and inclusion of diverse covariates hypothesized to explain variation in fitness components. Covariates to be considered include traits of individuals and their mothers and environmental conditions throughout life. <br/><br/>The study will continue to (1) provide detailed data on known-age individuals to other science projects and (2) educate and mentor the next generation of ecologists through academic and professional training and research experiences.
Phaeocystis antarctica is capable of forming blooms that are denser and more extensive than any other member of the Southern Ocean phytoplankton community. The factors that enable P Antarctica to dominate its competitors are not clear but are likely related to its colonial lifestyle. The goal of the project is to map all the reactions in metabolic pathways that are key to defining the ecological niche of Phaeocystis antarctica by developing a Pathway/Genome Database (PGDB) using Pathway Tools software. The investigators will assign proteins and enzymes to key pathways in P. Antarctica, continually improve and edit the database as the full Phaeocystis genome comes online, and host the database on the BioCyc webpage. The end product will be the first database for a eukaryotic phytoplankton genome where researchers can query extant metabolic pathways and place new proteins and enzymes of interest within metabolic networks. The risk is that a substantial percentage of catalytic enzymes may belong to pathways that are poorly characterized. The science impact is to link genomes to metabolic potential in the context of Phaeocystis life history but also in comparison to other organisms across the tree of life. The education and outreach includes work with a high school teacher and intern and curriculum development.
Spectacular blooms of Phaeocystis antarctica in the Ross Sea, Antarctica are the source of some of the world's highest concentrations of dimethylsulfoniopropionate (DMSP) and its volatile degradation product, dimethylsulfide (DMS). The flux of DMS from the oceans to the atmosphere in this region and its subsequent gas phase oxidation generates aerosols that have a strong influence on cloud properties and possibly climate. In the oceans, DMS and DMSP are quantitatively significant components of the carbon, sulfur, and energy flows in marine food webs, especially in the Ross Sea. Despite its central role in carbon and sulfur biogeochemistry in the Ross Sea, surprisingly little is known about the physiological functions of DMSP in P. Antarctica. The research will isolate and characterize DMSP lyases from P. antarctica, with the goal of obtaining amino acid and gene sequence information on these important enzymes. The physiological studies will focus on the effects of varying intensities of photosynthetically active radiation, with and without ultraviolet radiation as these are factors that we have found to be important controls on DMSP and DMS dynamics. The research also will examine the effects of prolonged darkness on the dynamics of DMSP and related compounds in P. antarctica, as survival of this species during the dark Antarctic winter and at sub-euphotic depths appears to be an important part of the Phaeocystis? ecology. A unique aspect of this work is the focus on measurements of intracellular MSA, which if detected, would provide strong evidence for in vivo radical scavenging functions for methyl sulfur compounds. The study will advance understanding of what controls DMSP cycling and ultimately DMS emissions from the Ross Sea and also provide information on what makes P. antarctica so successful in this extreme environment. The research will directly benefit and build on several interrelated ocean-atmosphere programs including the International Surface Ocean Lower Atmosphere Study (SOLAS) program. The PIs will participate in several activities involving K-12 education, High School teacher training, public education and podcasting through the auspices of the Dauphin Island Sea Lab Discovery Hall program and SUNY ESF. Two graduate students will be employed full time, and six undergraduates (2 each summer) will be trained as part of this project.
Abstract<br/><br/>The Ross Sea is believed to contributes a huge portion (~1/3) of the primary productivity of the Southern Ocean and is home to a similar large portion of the top predators (e.g. 38% of Adelie, 28% of Emperor penguins) of the Antarctic sea ice ecosystem. The trophic pathways in this system are complex in both space and time. One scenario for the Ross Sea ecosystem is that diatoms are grazed by krill, which are in turn the preferred food of fish, penguins and other predators. Phaeocystis colonies, on the other hand lead to grazing by pteropods and other organisms that are a non-favoured food source for top predators. Remotely sensed chlorophyll, indicating all phytoplankton, is then suggested to be a relatively poor predictor of penguin foraging efforts. This is also consistent with notion that algal species composition is very important to penguin grazing pressure, mediated by krill, and perhaps resulting in selective depletion. <br/><br/>This collaborative research sets out to use an autonomous glider, equipped with a range of sensors, and informed by satellite chlorophyll imagery to be combined with 3-dimenisonal active penguin tracking to their preferred foraging sites. The effect of localized grazing pressure of krill on the appearance and disappearance of algal blooms will also be followed. Overall the objective of the research is to reconcile and explain several years of the study of the foraging habits and strategies of (top predator) penguins at the Cape Crozier site (Ross Island), with the dynamics of krill and their supporting algal food webs. The use of a glider to answer a primarily ecological questions is subject to moderate to high risk, and is potentially transformative.
While changes in populations typically are tracked to gauge the impact of climate or habitat change, the process involves the response of individuals as each copes with an altered environment. In a study of Adelie penguins that spans 13 breeding seasons, results indicate that only 20% of individuals within a colony successfully raise offspring, and that they do so because of their exemplary foraging proficiency. Moreover, foraging appears to require more effort at the largest colony, where intraspecific competition is higher than at small colonies, and also requires more proficiency during periods of environmental stress. When conditions are particularly daunting, emigration dramatically increases, countering the long-standing assumption that Adélie penguins are highly philopatric. The research project will 1) determine the effect of age, experience and physiology on individual foraging efficiency; 2) determine the effect of age, experience, and individual quality on breeding success and survival in varying environmental and competitive conditions at the colony level; and 3) develop a comprehensive model for the Ross-Beaufort Island metapopulation dynamics. Broader impacts include training of interns, continuation of public outreach through the highly successful project website penguinscience.com, development of classroom materials and other standards-based instructional resources.
The emperor penguin dives deeper and longer, fasts longer, and endures the harshest weather conditions of all diving birds. It spends about four and half months per annum deep in Antarctic pack ice away from shore and stations, and thus is largely unavailable for study. This time includes preparation for the molt, and travel to the colony to breed, a time period in which great swings in body weight occur. This study will fill an important gap in what we know about the biology of the annual cycle of the emperor by examining the molt-post molt period. The P.I. proposes to traverse the Amundsen and Bellingshausen seas on the Oden, to locate and tag emperor penguins during the molt season. The objectives are to (1) Place satellite tags on 20 adult post molt birds to determine their route, rate of travel, and diving behavior as they return back to their breeding colonies, (2) Obtain an index of body condition, (3) Collect guano to determine the type of food consumed by emperor penguins in the region, (4) Conduct shipboard surveys to sight and plot the location and abundance of adult and juvenile birds on the ship's track. The PI hypothesizes that bird dives will be shallow during the initial post-molt phase, and that food will consist primarily of krill; that there will be differential dispersal of birds from the Ross Sea vs. Marie Byrd Land, with Ross Sea birds traveling farther; and that the greatest adult mortality occurs during the molt and early post molt period. Broader impacts include training of a post doc, a graduate student, and an aquarium volunteer. The P.I. also will present findings through a website, through public lectures, and in collaboration with the Birch aquarium.
This award supports a project to broaden the knowledge of annual accumulation patterns over the West Antarctic Ice Sheet by processing existing near-surface radar data taken on the US ITASE traverse in 2000 and by gathering and validating new ultra/super-high-frequency (UHF) radar images of near surface layers (to depths of ~15 m), expanding abilities to monitor recent annual accumulation patterns from point source ice cores to radar lines. Shallow (15 m) ice cores will be collected in conjunction with UHF radar images to confirm that radar echoed returns correspond with annual layers, and/or sub-annual density changes in the near-surface snow, as determined from ice core stable isotopes. This project will additionally improve accumulation monitoring from space-borne instruments by comparing the spatial-radar-derived-annual accumulation time series to the passive microwave time series dating back over 3 decades and covering most of Antarctica. The intellectual merit of this project is that mapping the spatial and temporal variations in accumulation rates over the Antarctic ice sheet is essential for understanding ice sheet responses to climate forcing. Antarctic precipitation rate is projected to increase up to 20% in the coming century from the predicted warming. Accumulation is a key component for determining ice sheet mass balance and, hence, sea level rise, yet our ability to measure annual accumulation variability over the past 5 decades (satellite era) is mostly limited to point-source ice cores. Developing a radar and ice core derived annual accumulation dataset will provide validation data for space-born remote sensing algorithms, climate models and, additionally, establish accumulation trends. The broader impacts of the project are that it will advance discovery and understanding within the climatology, glaciology and remote sensing communities by verifying the use of UHF radars to monitor annual layers as determined by visual, chemical and isotopic analysis from corresponding shallow ice cores and will provide a dataset of annual to near-annual accumulation measurements over the past ~5 decades across WAIS divide from existing radar data and proposed radar data. By determining if temporal changes in the passive microwave signal are correlated with temporal changes in accumulation will help assess the utility of passive microwave remote sensing to monitor accumulation rates over ice sheets for future decades. The project will promote teaching, training and learning, and increase representation of underrepresented groups by becoming involved in the NASA History of Winter project and Thermochron Mission and by providing K-12 teachers with training to monitor snow accumulation and temperature here in the US, linking polar research to the student?s backyard. The project will train both undergraduate and graduate students in polar research and will encouraging young investigators to become involved in careers in science. In particular, two REU students will participate in original research projects as part of this larger project, from development of a hypothesis to presentation and publication of the results. The support of a new, young woman scientist will help to increase gender diversity in polar research.
1042883/Mayewski<br/><br/>This award supports a project to analyze a deep ice core which will be drilled by a New Zealand research team at Roosevelt Island. The objectives are to process the ice core at very high resolution to (a) better understand phasing sequences in Arctic/Antarctic abrupt climate change, even at the level of individual storm events; (b) determine the impact of changes in the Westerlies and the Amundsen Sea Low on past/present/future climate change; (c) determine how sea ice extent has varied in the area; (d) compare the response of West Antarctica climate to other regions during glacial/interglacial cycles; and (e) determine how climate of the Ross Sea Embayment changed during the transition from Ross Ice Sheet to Ross Ice Shelf. The intellectual merit of the RICE deep ice core project is that it is expected to provide a 30kyr long (and possibly 150kyr long) extremely high-resolution view of climate change in the Ross Sea Embayment Region and data essential to test and understand critical questions that have emerged as a consequence of the recent synthesis of Antarctic and Southern Ocean climate change presented in the Scientific Commission for Antarctic Research document: Antarctic Climate Change and the Environment (ACCE, 2009). Ice core processing and analysis will be performed jointly by University of Maine and the collaborators from New Zealand. Co-registered sampling for all chemical analyses will be accomplished by a joint laboratory effort at the IGNS NZ ice core facility using a continuous melter system developed by the University of Maine. The RICE deep ice core record will provide information necessary in unraveling the significance of multi-millennial underpinning for climate change and in the understanding of observed and projected climate change in light of current dramatic human impact on Antarctica and the Southern Ocean. The broader impacts of the project include the fact that two CCI graduate students will be funded through the project, and will be involved in all aspects of field research, core sampling, sample processing, analytical and numerical analyses, data interpretation, writing of manuscripts, and presentation of results at national and international conferences. Data and ideas developed in this project and associated work will be used in several courses taught at the University of Maine. Innovative cyberinfrastructure will be incorporated into this work and ground breaking analytical technologies, and data access/storage tools will be used.
Geochemical studies of single mineral grains in rocks can be probed to reconstruct the history of our planet. The mineral zircon (ZrSiO4) is of unique importance in that respect because of its reliability as a geologic clock due to its strong persistence against weathering, transport and changes in temperature and pressure. Uranium-Lead (U-Pb) dating of zircon grains is, perhaps, the most frequently employed method of extracting time information on geologic processes that shaped the continental crust, and has been used to constrain the evolution of continents and mountain belts through time. In addition, the isotopic composition of the element Hafnium (Hf) in zircon is used to date when the continental crust was generated by extraction of magma from the underlying mantle. Melting of rocks in the mantle and deep in the continental crust are key processes in the evolution of the continents, and they are recorded in the Hf isotopic signatures of zircon. Although the analytical procedures for U-Pb dating and Hf isotope analyses of zircon are robust now, our understanding of zircon growth and its exchange of elements and isotopes with its surrounding rock or magma are still underdeveloped. The focus of the proposed study, therefore, is to unravel the evolution of zircon Hf isotopes in rocks that were formed deep in the Earth?s crust, and more specifically, to apply these isotopic methods to rocks collected in Dronning Maud Land (DML), East Antarctica.<br/><br/>Dronning Maud Land (DML) occupied a central location during the formation of supercontinents ? large landmasses made up of all the continents that exist today - more than 500 million years ago. It is currently thought that supercontinents were formed and dismembered five or six times throughout Earth?s history. The area of DML is key for understanding the formation history of the last two supercontinents. The boundaries of continents that were merged to form those supercontinents are most likely hidden in DML. In this study, the isotopic composition of zircon grains recovered from DML rocks will be employed to identify these boundaries across an extensive section through the area. The rock samples were collected by the investigator during a two-month expedition to Antarctica in the austral summer of 2007?2008. The results of dating and isotope analyses of zircon of the different DML crustal domains will deliver significant insight into the regional geology of East Antarctica and its previous northern extension into Africa. This has significance for the reconstruction of the supercontinents and defining the continental boundaries in DML.
Intellectual Merit: <br/>The PIs propose to quantify the hillslope water, solute, and carbon budgets for Taylor Valley in the McMurdo Dry Valleys, using water tracks to investigate near-surface geological processes and challenge the paradigm that shallow groundwater is minimal or non-exixtant. Water tracks are linear zones of high soil moisture that route shallow groundwater downslope in permafrost dominated soils. Four hypotheses will be tested: 1) water tracks are important pathways for water and solute transport; 2) water tracks transport more dissolved silica than streams in Taylor Valley indicating they are the primary site of chemical weathering for cold desert soils and bedrock; 3) water tracks that drain highland terrains are dominated by humidity-separated brines while water tracks that drain lowland terrains are dominated by marine aerosols; 4) water tracks are the sites of the highest terrestrial soil carbon concentrations and the strongest CO2 fluxes in Taylor Valley and their carbon content increases with soil age, while carbon flux decreases with age. To test these hypotheses the PIs will carry out a suite of field measurements supported by modeling and remote sensing. They will install shallow permafrost wells in water tracks that span the range of geological, climatological, and topographic conditions in Taylor Valley. Multifrequency electromagnetic induction sounding of the upper ~1 m of the permafrost will create the first comprehensive map of soil moisture in Taylor Valley, and will permit direct quantification of water track discharge across the valley. The carbon contents of water track soils will be measured and linked to global carbon dynamics.<br/><br/>Broader impacts: <br/>Non-science majors at Oregon State University will be integrated into the proposed research through a new Global Environmental Change course focusing on the scientific method in Antarctica. Three undergraduate students, members of underrepresented minorities, will be entrained in the research, will contribute to all aspects of field and laboratory science, and will present results at national meetings.
The research combines interdisciplinary study in geology, paleontology, and biology, using stable isotope and radiocarbon analyses, to examine how climate change and resource utilization have influenced population distribution, movement, and diet in penguins during the mid-to-late Holocene. Previous investigations have demonstrated that abandoned colonies contain well-preserved remains that can be used to examine differential responses of penguins to climate change in various sectors of Antarctica. As such, the research team will investigate abandoned and active pygoscelid penguin (Adelie, Chinstrap, and Gentoo) colonies in the Antarctic Peninsula and Ross Sea regions, and possibly Prydz Bay, in collaboration with Chinese scientists during four field seasons. Stable isotope analyses will be conducted on recovered penguin tissues and prey remains in guano to address hypotheses on penguin occupation history, population movement, and diet in relation to climate change since the late Pleistocene. The study will include one Ph.D., two Masters and 16 undergraduate students in advanced research over the project period. Students will be exposed to a variety of fields, the scientific method, and international scientific research. They will complete field and lab research for individual projects or Honor's theses for academic credit. The project also will include web-based outreach, lectures to middle school students, and the development of interactive exercises that highlight hypothesis-driven research and the ecology of Antarctica. Two undergraduate students in French and Spanish languages at UNCW will be hired to assist in translating the Web page postings for broader access to this information.
Intellectual Merit: <br/>Sinking particles are a major element of the biological pump and they are commonly assigned to two fates: mineralization in the water column and accumulation at the seafloor. However, there is another fate of export hidden within the vertical decline of carbon, the transformation of sinking organic matter to fine suspended and/or dissolved organic fractions. This process has been suggested but has rarely been observed or quantified. As a result, it is presumed that the solubilized fraction is largely mineralized over short time scales. However, global ocean surveys of dissolved organic carbon are demonstrating a significant water column accumulation of organic matter under high productivity environments. This proposal will investigate the transformation of organic particles from sinking to solubilized phases of the export flux in the Ross Sea. The Ross Sea experiences high export particle production, low dissolved organic carbon export with overturning circulation, and the area has a predictable succession of production and export events. In addition, the basin is shallow (< 000 m) so the products the PIs will target are relatively concentrated. To address the proposed hypothesis, the PIs will use both well-established and novel biochemical and optical measures of export production and its fate. The outcomes of this work will help researchers close the carbon budget in the Ross Sea.<br/><br/>Broader impacts: <br/>This research will support graduate and undergraduate students and will provide undergraduates and pre-college students with field-based research experience. Scientifically, this research will increase understanding of carbon sinks in the Ross Sea and will help develop new tools for identifying, quantifying, and tracking that carbon. The PIs will interface with K-12 students through daily reports from the field and through educational modules developed by several of the PIs in collaboration with science education specialists and college students. A K-12 educator will be included on the research cruises. Outreach will be through COSEE Florida and the Maritime Center in Norfolk, VA.
The Ross Sea continental shelf is one of the most productive areas in the Southern Ocean, and may comprise a significant, but unaccounted for, oceanic CO2 sink, largely driven by phytoplankton production. The processes that control the magnitude of primary production in this region are not well understood, but data suggest that iron limitation is a factor. Field observations and model simulations indicate four potential sources of dissolved iron to surface waters of the Ross Sea: (1) circumpolar deep water intruding from the shelf edge; (2) sediments on shallow banks and nearshore areas; (3) melting sea ice around the perimeter of the polynya; and (4) glacial meltwater from the Ross Ice Shelf. The principal investigators hypothesize that hydrodynamic transport via mesoscale currents, fronts, and eddies facilitate the supply of dissolved iron from these four sources to the surface waters of the Ross Sea polynya. These hypotheses will be tested through a combination of in situ observations and numerical modeling, complemented by satellite remote sensing. In situ observations will be obtained during a month-long cruise in the austral summer. The field data will be incorporated into model simulations, which allow quantification of the relative contributions of the various hypothesized iron supply mechanisms, and assessment of their impact on primary production. The research will provide new insights and a mechanistic understanding of the complex oceanographic phenomena that regulate iron supply, primary production, and biogeochemical cycling. The research will thus form the basis for predictions about how this system may change in a warming climate. The broader impacts include training of graduate and undergraduate students, international collaboration, and partnership with several ongoing outreach programs that address scientific research in the Southern Ocean. The research also will contribute to the goals of the international research programs ICED (Integrated Climate and Ecosystem Dynamics) and GEOTRACES (Biogeochemical cycling and trace elements in the marine environment).
Time series data, from ocean moorings, on key aspects of evolving ocean properties are of considerable importance in assessing the condition of the ocean system. They are needed, for example, their understand how the oceans are warming, and how they continue to uptake greenhouse gases such as CO2. <br/><br/>The Cape Adare Long Term Mooring (CALM) program goal was to observe the bottom water export from the Ross Sea to the deep ocean. To accomplish this two instrumented moorings were set on the continental slope off Cape Adare (western Ross Sea, Antarctica), positioned to capture the export of Antarctic Bottom Water (AABW), some of the coldest and densest water found in the global ocean. Data records for the moorings spans over some four years in this very remote part of the ocean. The CALM analysis will address some specific objectives:<br/>? Characterize the temperature, salinity and current variability associated with the Ross Sea AABW export.<br/>? Examine the linkages between observed variability to regional tides, atmosphere and sea ice forcing.<br/>? Relate the Ross Sea AABW export fluctuations to the larger scale climate system dynamics, such as ENSO and SAM, and to AABW formation along other margins of Antarctica, e.g. the Weddell Sea
Many persistent organic pollutants (POPs), though banned in the U.S. since the 1970s, remain in the environment and continue to reach hitherto pristine regions such as the Arctic and Antarctic. The overall goals of this RAPID project are to better understand the remobilization of POPs from melting glaciers in the Antarctic, and their transfer into the food-web. Legacy POPs have characteristic chemical signatures that will be used ascertain the origin of POPs in the Antarctic atmosphere and marine food-web. Samples that were collected in 2010 will be analyzed for a wide range of legacy POPs, and their behavior will be contrasted with results for emerging contaminants. The intellectual merit of the proposed research combines (a) the use of chemical signatures to assess whether melting glaciers are releasing legacy POPs back into the Antarctic marine ecosystem, and (b) a better understanding of the food-web dynamics of legacy POPs versus emerging organic pollutants.<br/><br/>The broader impacts of the proposed research project will include the training of the next generation of scientists through support for a graduate student and a postdoctoral scholar. As well, this work will result in a better understanding of the relationship between pollutants, trophic food web ecology and global climate change in the pristine Antarctic ecosystem.
Identifying the basic habitat requirements of Antarctic predators is fundamental to understanding how they will respond to the human-induced challenges of commercial fisheries and climate change. This understanding can only be achieved if the underlying linkages to physical processes are related to animal movements. As part of the international Retrospective Analysis of Antarctic Tracking Data (RAATD) organized by the SCAR Expert Group of Birds and Marine Mammals, this research will collate and synthesize tracking data from crabeater seals, Lobodon carcinophagus, and Weddell seals, Leptonychotes weddelli. These data will be combined with all available data from the Southern Ocean that has been collected by researchers from Norway, United Kingdom, Germany, Australia and the USA. These data will be analyzed using a common analytical approach and synthesized into a synoptic view of these two species across the Southern Ocean. The diving and movement patterns will be examined for each species. As well, the total home range and core habitat utilization patterns for each species and region will be determined. This study will develop global habitat maps for each species based on physical and biological attributes of their "hot-spots" and then overlay all the species specific maps to identify multi-species areas of ecological significance. Broader impacts include support and training for a postdoctoral scholar, the production of a publicly available database and the participation in an international data synthesis effort.
Intellectual Merit: <br/>The PI will collect samples to extend the magneto-stratigraphic record of late Cretaceous sediments of the James Ross Basin, Antarctica. RAPID support will allow him to take advantage of an invitation from the Instituto Antartico Argentino (IAA) to participate on an excursion to James Ross Island in the Antarctic Peninsula. The PI hopes to collect samples that will refine the position of several geomagnetic reversals between the end of the Cretaceous long normal Chron and the lower portion of Chron 31R. The Brandy Bay locality targeted by this expedition is the best place in the basin for calibrating the biostratigraphic position of the top of the Cretaceous Long Normal Chron, which is one of the most reliable correlation horizons in the entire Geological Time Scale.<br/><br/>Broader impacts: <br/>The top of the Cretaceous long normal Chron is not properly correlated to southern hemisphere biostratigraphy. Locating this event will be a major addition to understanding geological time. This expedition will provide opportunities for an undergraduate student. This project is based on a productive collaboration with an Argentine scientist.
Abstract<br/><br/>Researchers will explore the use of a distributed temperature sensing monitoring system (DTS), using fiber-optical (FO) technology, as the basis of a sustainable, sub-ice cavity sensing array. FO cable systems, such as may be deployed through a hot-water drilled hole through an ice shelf, passing through the underlying cavity to the sea floor, are capable of measuring temperatures down fiber at 1 meter intervals, and at time frequencies as high as 15 seconds. DTS FO systems operate via optical time domain reflectometry along the fiber waveguide using inelastic backscatter of coherent laser light as a probe beam in the FO environment.<br/><br/>The introduction of new technologies to the harsh environmental conditions of the Antarctic are often associated with high risk. However, the potential rewards of this approach (e.g. multiyear capability, minimal submerged mechanical or electrical components that may fail, relative simplicity of deployment and measurement principle, yet yielding distributed real time and spatial observation) are attractive enough to conduct a pilot project at a field-ready location (McMurdo). <br/><br/>Current indications are that the instability of some of the world's largest ice sheets located around the Antarctic and Greenland may be caused by the presence of warming, deep ocean waters, shoaling over continental shelves, and melting the underside of floating ice shelves. Additional knowledge of the temporal and spatial variability of the temperature fields underneath terminal ice shelves, such as those draining the West Antarctic Ice Sheet, are needed to accurately project future global climate effects on ice-shelf ocean interactions, and in order to inform societal and technological aspects of adaption to changing sea-level.
This award provides support for "EAGER: Handbook of Hot Water Drill System (HWDS) Design Considerations and Best Practices" from the Antarctic Integrated System Science within the Office of Polar Programs. More and more science projects are proposing to use hot-water drilling systems (HWDS) to rapidly and/or cleanly access glacial and subglacial systems. To date the hot-water drill systems have been developed in isolation, and no attempt has been made to gather information about the different systems in one place. This proposal requests funds to document existing HWDS, and to then assess the design, testing, and development of a hot-water drill system that will be integrated with the evolving over-ice traverse capability of the USAP program.<br/><br/>Intellectual Merit: A working handbook of best practices for hot-water drill design systems, including safety considerations, is long overdue, and will 1) provide suggestions for optimizing current systems; 2) contribute in the very near term to already funded projects such as WISSARD (Whillans Ice Stream Subglacial Access and Research Drilling); and 3) fit the long-term needs of the Antarctic science community who have identified rapid and clean access to glacial and subglaical environments as a top priority for the next decades. The collected information will be used for community education and training, will discuss potential design and operational trade-offs, and will identify ways to optimize the capabilities of an integrated USAP traverse and HWDS infrastructure. EAGER funding for this project is warranted because such a handbook has not been tried before, and needs to be shown to be doable prior to larger investments in such compilations. It fits the AISS (Antarctic Integrated System Science) program as an optimized HWDS will meet the needs of many different Antarctic research disciplines including biology, geology, glaciology, and oceanography.<br/><br/>Broader Impacts: The proposed work is being done on behalf of the Antarctic research community, and will seek to capture the knowledge of experienced hot-water drill engineers who are nearing retirement, and to educate the next generation of hot-water drillers and engineers. The PI indicates he will work with the owners of such systems both within the US and abroad. Identification of best practices in hot-water drilling will save several different Antarctic research communities significant time, effort, and funding in the future.
The stability of the marine West Antarctic Ice Sheet (WAIS) remains an important, unresolved problem for predicting future sea level change. Recent studies indicate that the mass balance of the ice sheet today may be negative or positive. The apparent differences may stem in part from short-term fluctuations in flow. By comparison, geologic observations provide evidence of behavior over much longer time scales. Recent work involving glacial-geologic mapping, dating and ice-penetrating radar surveys suggests that deglaciation of both the Ross Sea Embayment and coastal Marie Byrd Land continued into the late Holocene, and leaves open the possibility of ongoing deglaciation and grounding-line retreat. However, previous work in the Ross Sea Embayment was based on data from just three locations that are all far to the north of the present grounding line. Additional data from farther south in the Ross Sea Embayment are needed to investigate whether recession has ended, or if the rate and pattern of deglaciation inferred from our previous study still apply to the present grounding line. This award provides support to reconstruct the evolution of Reedy Glacier, in the southern Transantarctic Mountains, since the Last Glacial Maximum (LGM). Because Reedy Glacier emerges from the mountains above the grounding line, its surface slope and elevation should record changes in thickness of grounded ice in the Ross Sea up to the present day. The deglaciation chronology of Reedy Glacier therefore can indicate whether Holocene retreat of the WAIS ended thousands of years ago, or is still continuing at present. This integrated glaciologic, glacial-geologic, and cosmogenic-isotope exposure- dating project will reconstruct past levels of Reedy Glacier. Over two field seasons, moraines will be mapped, dated and correlated at sites along the length of the glacier. Radar and GPS measurements will be made to supplement existing ice thickness and velocity data, which are needed as input for a model of glacier dynamics. The model will be used to relate geologic measurements to the grounding-line position downstream. Ultimately, the mapping, dating and ice-modeling components of the study will be integrated into a reconstruction that defines changes in ice thickness in the southern Ross Sea since the LGM, and relates these changes to the history of grounding-line retreat. This work directly addresses key goals of the West Antarctic Ice Sheet Initiative, which are to understand the dynamics, recent history and possible future behavior of the West Antarctic Ice Sheet.
Advances in molecular techniques have expanded our understanding of soil microbial communities, and raised important questions about regional and global patterns in microbial diversity. The proposed research will investigate the composition and activity of microbial communities across a range of geochemical and hydrologic soil conditions, and over local to regional scales in the Transantarctic Mountains, in order to assess controls over microbial biogeography. The research targets two areas in the Transantarctic mountains, the McMurdo Dry Valleys, and the Beardmore Glacier region further south, the latter representing an underexplored and inarguably more extreme soil environment. The research project will adopt an integrated approach, using molecular techniques and in situ assessment of biological activity in a quantitative biogeographical framework, with the goal of distinguishing fine versus broad scale controls over microbial community structure. The research is essential to determining the basic trophic status of extreme microbial food webs, and their sensitivity to climate change. The investigators will engage secondary and post-secondary educators through first person outreach as well as web-based communications and exercises. Two postdoctoral scientists will be trained in an interdisciplinary and international setting.
Intellectual Merit: <br/>Because of extensive ice cover and sparse remote-sensing data, the geology of the Precambrian East Antarctic Shield (EAS) remains largely unexplored with information limited to coastal outcrops from the African, Indian and Australian sectors. The East Antarctic lithosphere is globally important: as one of the largest coherent Precambrian shields, including rocks as old as ~3.8 Ga, it played an important role in global crustal growth; it is a key piece in assembly of the Rodinia and Gondwana supercontinents; it is the substrate to Earth?s major ice cap, including numerous sub-glacial lakes, and influences its thermal state and mechanical stability; and its geotectonic association with formerly adjacent continental blocks in South Africa, India and Australia suggest that it might harbor important mineral resources. This project will increase understanding of the age and composition of the western EAS lithosphere underlying and adjacent to the Transantarctic Mountains (TAM) using U-Pb ages, and Hf- and O-isotope analysis of zircon in early Paleozoic granitoids and Pleistocene glacial tills. TAM granites of the early Paleozoic Ross Orogen represent an areally extensive continental-margin arc suite that can provide direct information about the EAS crust from which it melted and/or through which it passed. Large rock clasts of igneous and metamorphic lithologies entrained in glacial tills at the head of major outlet glaciers traversing the TAM provide eroded samples of the proximal EAS basement. Zircons in these materials will provide data about age and inheritance (U-Pb), crustal vs. mantle origin (O isotopes), and crustal sources and evolution (Hf isotopes). Integrated along a significant part of the TAM, these data will help define broader crustal provinces that can be correlated with geophysical data and used to test models of crustal assembly. <br/><br/>Broader impacts: <br/>This project will provide a research opportunity for undergraduate and graduate students. Undergraduates will be involved as Research Assistants in sample preparation, imaging, and analytical procedures, and conducting their own independent research. The two main elements of this project will form the basis of MS thesis projects for two graduate students at UMD. Through this project they will gain a good understanding of petrology, isotope geochemistry, and analytical methods. The broader scientific impacts of this work are that it will help develop a better understanding of the origin and evolution of East Antarctic lithosphere underlying and adjacent to the TAM, which will be of value to the broader earth science and glaciological community. Furthermore, knowledge of East Antarctic geology is of continuing interest to the general public because of strong curiosity about past supercontinents, what?s under the ice, and the impact of global warming on ice-sheet stability.
Genome-enabled biology provides a foundation for understanding the genetic basis of organism-environment interactions. . The research project links gene expression, genome methylation, and metabolic rates to assess the mechanisms of environmental adaptation (temperature) across multiple generations in a polar, and closely related temperate, polychaete. By comparing these two species, the research will assess how a polar environment shapes responses to environmental stress. This work will produce: 1) a database of full transcriptome (gene specific) profiling data for the polar polychaete cultured at two temperatures; 2) the contribution of genome methylation to the suppression of gene transcription activities; 3) the linkage between shifts in mRNA pools and total cellular activities (as ATP consumption via respiration); 4) an assessment of the inheritance of patterns of gene expression and metabolic activities across three generations; and 5) a simple demographic model of the polar polychaete population dynamics under normal and 'global-warming' temperature scenarios. Broader impacts include two outreach activities. The first is a mentoring program, where African-American undergraduate students spend 1.5 years working on a research project with a UD faculty member (2 summers plus their senior academic year). The second is a children's display activity at UD?s School of Marine Science "Coast Day".
Collaborative With: McPhee 0732804, Holland 0732869, Truffer 0732730, Stanton 0732926, Anandakrishnan 0732844 <br/>Title: Collaborative Research: IPY: Ocean-Ice Interaction in the Amundsen Sea Sector of West Antarctica<br/><br/>The Office of Polar Programs, Antarctic Integrated and System Science Program has made this award to support an interdisciplinary study of the effects of the ocean on the stability of glacial ice in the most dynamic region the West Antarctic Ice Sheet, namely the Pine Island Glacier in the Amundsen Sea Embayment. The collaborative project builds on the knowledge gained by the highly successful West Antarctic Ice Sheet program and is being jointly sponsored with NASA. Recent observations indicate a significant ice loss, equivalent to 10% of the ongoing increase in sea-level rise, in this region. These changes are largest along the coast and propagate rapidly inland, indicating the critical impact of the ocean on ice sheet stability in the region. While a broad range of remote sensing and ground-based instrumentation is available to characterize changes of the ice surface and internal structure (deformation, ice motion, melt) and the shape of the underlying sediment and rock bed, instrumentation has yet to be successfully deployed for observing boundary layer processes of the ocean cavity which underlies the floating ice shelf and where rapid melting is apparently occurring. Innovative, mini ocean sensors that can be lowered through boreholes in the ice shelf (about 500 m thick) will be developed and deployed to automatically provide ocean profiling information over at least three years. Their data will be transmitted through a conducting cable frozen in the borehole to the surface where it will be further transmitted via satellite to a laboratory in the US. Geophysical and remote sensing methods (seismic, GPS, altimetry, stereo imaging, radar profiling) will be applied to map the geometry of the ice shelf, the shape of the sub ice-shelf cavity, the ice surface geometry and deformations within the glacial ice. To integrate the seismic, glaciological and oceanographic observations, a new 3-dimensional coupled ice-ocean model is being developed which will be the first of its kind. NASA is supporting satellite based research and the deployment of a robotic-camera system to explore the environment in the ocean cavity underlying the ice shelf and NSF is supporting all other aspects of this study. <br/><br/>Broader impacts: This project is motivated by the potential societal impacts of rapid sea level rise and should result in critically needed improvements in characterizing and predicting the behavior of coupled ocean-ice systems. It is a contribution to the International Polar Year and was endorsed by the International Council for Science as a component of the "Multidisciplinary Study of the Amundsen Sea Embayment" proposal #258 of the honeycomb of endorsed IPY activities. The research involves substantial international partnerships with the British Antarctic Survey and the University of Bristol in the UK. The investigators will partner with the previously funded "Polar Palooza" education and outreach program in addition to undertaking a diverse set of outreach activities of their own. Eight graduate students and one undergraduate as well as one post doc will be integrated into this research project.
Emperor penguins (Aptenodytes forsteri) and leopard seals (Hydrurga leptonyx) are iconic, top predators in Antarctica. Understanding their physiological ecology is essential to the assessment of their adaptability to the threats of climate change, pollution, and overfishing. The proposed research has multipronged objectives. Prior results suggest that Emperor penguins have flexible (vs. static) aerobic dive limits (ADL) that vary with the type of dive, and that the role of heart rate in utilization of oxygen stores also varies with dive type. A series of physiological measurements are proposed with backpack electrocardiogram recorders, that will allow further delineation of patterns and interrelationships among heart rate, dive behavior, and oxygen stores. Importantly, the research will be done on free diving emperors, and not individuals confined to a dive hole, thereby providing a more genuine measure of diving physiology and behavior. A separate objective is to examine foraging behavior of leopard seals, using a backpack digital camera and time depth recorder. Leopard seal behavior and prey intake is poorly quantified, but known to be significant. Accordingly the research is somewhat exploratory but will provide important baseline data. Finally, the P.I. proposes to continue long term overflight censuses of Emperor penguin colonies in the Ross Sea. Broader impacts include collaboration with National Geographic television, graduate student training, and development of sedation techniques for leopard seals.
Intellectual Merit:<br/>The focus of this proposal is to collect fossil plants and palynomorphs from Permian-Triassic (P-T) rocks of the central Transantarctic Mountains (CTM), together with detailed data on sedimentologic and paleoecologic depositional environments. Fossil plants are important climate proxies that offer a unique window into the past, and the CTM fossils are an important source of data on the ways that plants responded to a strongly seasonal, polar light regime during a time of global change. The proposed project uses paleobotanical expertise, integrated with detailed sedimentology and stratigraphy, to reconstruct Permian-Triassic plant communities and their paleoenvironments. This interdisciplinary approach could uncover details of Antarctica?s complex late Paleozoic and Mesozoic environmental and climatic history which included: 1) deglaciation, 2) development and evolution of a post-glacial landscape and biota, 3) environmental and biotic change associated with the end-Permian mass extinction, 4) environmental recovery in the earliest Triassic, 5) strong, possible runaway Triassic greenhouse, and 6) widespread orogenesis and development of a foreland basin system. The PIs will collect compression floras both quantitatively and qualitatively to obtain biodiversity and abundance data. Since silicified wood is also present, the PIs will analyze tree rings and growth in a warm, high-latitude environment for which there is no modern analogue. Fossil plants from the CTM can provide biological and environmental information to: 1) interpret paleoclimate when Gondwana moved from icehouse to greenhouse conditions; 2) trace floral evolution across the P-T boundary; 3) reconstruct Antarctic plant life; 4) further understanding of plant adaptations to high latitudes. The Intellectual Merit of the research includes: 1) tracing floral evolution after the retreat of glaciers; 2) examining floral composition and diversity across the PTB; and 3) obtaining data on the recovery of these ecosystems in the Early Triassic, as well as changes in floral cover and diversity in the Early-Middle Triassic. Antarctica is the only place on Earth that includes extensive outcrops of terrestrial rocks, combined with widespread and well-preserved plant fossils, which spans this crucial time period.<br/><br/>Broader impacts:<br/>The broader impacts include public outreach; teaching, and mentoring of women and underrepresented students; mentoring graduate student, postdoctoral, and new faculty women; development of an inquiry-based workshop on Antarctic paleoclimate with the Division of Education, KU Natural History Museum; continuing support of workshops for middle school girls in science via the Expanding Your Horizons Program, Emporia State University, and the TRIO program, KU; exploring Antarctic geosciences through video/computer links from McMurdo Station and satellite phone conferences from the field with K-12 science classes in Wisconsin and Kansas, and through participation in the NSF Research Experiences for Teachers program at the University of Wisconsin.
Intellectual Merit: <br/>This research will place the subsidence history of the southern Victoria Land Basin into a quantitative geodynamic context and will assess the influence of flexure associated with late Neogene volcanic loading of the crust by the Erebus Volcanic Group. This will be done by extending geodynamic models of extension in the West Antarctic Rift System to include extensional hiatuses hypothesized to have occurred during the Late Paleogene and Miocene, and by developing a new geodynamic model of volcanic loading and associated lithosphere flexure. Finite element and finite difference modeling methods will be used. In the first phase of the project, a series of extensional geodynamic models will be developed to examine the effect that proposed extensional hiatuses have on the style of extension, with emphasis placed on developing a process based understanding of the change in rift style from diffuse during the Late Cretaceous to more focused during the Cenozoic. The models will test the hypotheses that extensional hiatuses led to the change in rifting style, and will place constraints on the timing and duration of the hiatuses. The second phase of the project will use the thermal and rheological properties of the previous models to constrain the flexural rigidity of the lithosphere in order to model the flexural response to volcanic loading to test the hypotheses that flexural subsidence contributed to cyclic changes between grounded and floating ice at the ANDRILL AND-1A site, complicating interpretations of the climatic record from this core, and that flexure contributes to the stress orientation at the AND-2B site, which is inconsistent with the expected regional extensional stress orientation.<br/><br/>Broader impacts: <br/>The project will train an undergraduate student and an M.S. student. Outreach activities include a planned series of talks at regional high schools, junior colleges, and 4-year colleges that have geology programs.
This award supports a program of ground-based geophysical measurements to map in detail the spatial variations of ice flow, accumulation rate, internal layering and ice thickness at the sites which have been identified as promising locations to drill the next deep ice core in West Antarctica. The main investigative tools are a high- and low-frequency ice penetrating radar to image the topography of internal layers and the bed, repeat GPS surveys to calculate the present day surface velocity field, synthetic aperture radar (SAR) interferometry to calculate the regional velocity field, and short firn cores to calculate present day accumulation rates. The data which will be collected will be used to as input to time-dependent ice flow and temperature models that will predict depth variation of age, layer thickness, and temperature. As well as yielding an estimate of expected conditions before drilling, the mismatch between the model prediction and data eventually recovered from the core will help infer thinning and climate (accumulation and temperature) histories for the region. The Western Divide, between the Ross Sea Embayment and the Amundsen Sea, has been identified as the region which best satisfies the criteria which have been established for a deep drilling site. Preliminary site selection using airborne geophysical methods has identified several potential drill sites on the Western Divide where the climate record should be best preserved. This work will contribute in a major way to the final site selection for the next deep ice core in West Antarctica.
Intellectual Merit: <br/>The PIs propose to study the stability and dynamics of the East Antarctic ice sheet during the Pliocene in the area of the Wilkes and Aurora subglacial basins. Models indicate the ice sheet is most sensitive to warming in these low-lying areas. This study is important as there is very little direct evidence about which parts of the East Antarctic ice sheet became unstable under warm conditions. In a pilot study the PIs have shown that the isotopic geochemical signature of downcore ice-rafted debris (IRD) can be linked to continental source areas indicating which parts of the ice sheet reached the coast and calved IRD-bearing icebergs. Their initial results suggest rapid iceberg discharge from the Wilkes Land and Adélie Land coastal areas at times in the late Miocene and early Pliocene. In this study the PIs will analyze IRD from IODP sediment cores collected on the continental rise off East Antarctica. By analyzing 40Ar/39Ar ages of hornblende IRD grains, U-Pb ages of zircons, and Sm-Nd isotopes of the fine fraction of several IRD-rich layers for each core, they will be able to fingerprint continental source areas that will indicated ice extent and dynamics on East Antarctica. The PIs will also carry out detailed studies across a few of these layers to characterize the anatomy of the ice-rafting event and better understand the mechanism of ice destabilization.<br/><br/>Broader impacts: <br/>The data collected will be important for scientists in a broad variety of fields. The project will involve one undergraduate student and one summer intern at LDEO, and a graduate student at Imperial College London. The project will expose to cutting edge methodologies as well as an international research team. Data from the project will be deposited in the online databases (SedDB) and all results and methods will be made available to the scientific community through publications in peer-reviewed journals and attendance at international conferences.
The relatively pristine Antarctic continent with its extensive maritime zone represents a unique location on the planet to investigate the long distance aerial transport and deposition of marine microorganisms. The vast extent of new sea ice that forms each winter around the continent results in large numbers of frost flowers, delicate ice-crystal structures of high salt content that form on the surface of the ice and are readily dispersed by wind. The proposed research builds on earlier work in the Arctic and tests the new hypothesis that wind-borne frost flowers provide an effective mechanism for the transport of marine bacteria over long distances, one that can be uniquely sourced and tracked by the frost flower salt signature in the Antarctic realm. A highly resolved genomic snapshot of the microbial community will be acquired at each stage in the transport path, which will track decreasing fractions of the marine microbial community as it freezes into sea ice, incorporates into frost flowers, converts to aerosols, and ultimately deposits within continental snowpack. En route from sea ice to snowpack, marine bacteria will be exposed to an array of environmental stresses, including high salinity, low temperatures, UV light and potential desiccation. A parallel proteomic analysis will enable an evaluation of the microbial response to these extreme conditions and potential survival mechanisms that allow persistence or eventual colonization of deposition sites across Antarctica. <br/><br/>Current understanding of microbes in the Antarctic atmosphere is based on a limited number of microscopic and culture-based assays and a single report of low-resolution 16S RNA gene sequence analysis. The research will broadly impact understanding of atmospheric microbiology, from source to deposition, and various issues of microbial survival, colonization, endemism, and diversity under extreme conditions. In addition to venues that reach the scientific community, the research team will develop a permanent multi-media and artifact-based exhibit on Antarctic Microbial Transport that will be showcased at Seattle's Pacific Science Center (PSC), which educates nearly a million visitors annually.
The proposed work will investigate changes in the compositional variation of glacial tills over time across two concentric sequences of Pleistocene moraines located adjacent to the heads of East Antarctic outlet glaciers in the Transantarctic Mountains (TAM). The chronologic framework for this work will be generated from cosmogenic exposure ages of boulders on prominent morainal ridges. The PIs hypothesize that variations in till composition may indicate a change in ice flow direction or a change in the composition of the original source area, while ages of the moraines provide a long-term terrestrial perspective on ice sheet dynamics. Both results are vital for modeling experiments that aim to reconstruct the East Antarctic Ice Sheet and assess its role in the global climate system and its potential impact on global sea level rise. The variation of till compositions through time also allows for a more accurate interpretation of sediment cores from the Ross Sea and the Southern Ocean. Additionally, till exposures at the head of some East Antarctic outlet glaciers have been shown to contain subglacial material derived from East Antarctic bedrock, providing a window through the ice to view East Antarctica?s inaccessible bedrock. Till samples will be collected from two well-preserved sequences of moraine crests at Mt. Howe (head of Scott Glacier) and Mt. Achernar (between Beardmore and Nimrod Glaciers). Each size fraction in glacial till provides potentially valuable information, and the PIs will measure the petrography of the clast and sand fractions, quantitative X-ray diffraction on the crushed <2mm fraction, elemental abundance of the silt/clay fraction, and U/Pb of detrital zircons in the sand fraction. Data collection will rely on established methods previously used in this region and the PIs will also explore new methods to assess their efficacy. On the same moraines crests sampled for provenance studies, the PIs will sample for cosmogenic surface exposure analyses to provide a chronologic framework at the sites for provenance changes through time. <br/><br/>Broader Impact <br/>The proposed research involves graduate and undergraduate training in a diverse array of laboratory methods. Students and PIs will be make presentations to community and campus groups, as well as conduct interviews with local news outlets. The proposed work also establishes a new, potentially long-term, collaboration between scientists at IUPUI and LDEO and brings a new PI (Kaplan) into the field of Antarctic Earth Sciences.
Intellectual Merit: <br/>Until recently, wetted soils in the Dry Valleys were generally only found adjacent to streams and lakes. Since the warm austral summer of 2002, numerous ?wet spots? have been observed far from shorelines on relatively flat valley floor locations and as downslope fingers of flow on valley walls. The source of the water to wet these soils is unclear, as is the spatial and temporal pattern of occurrence from year to year. Their significance is potentially great as enhanced soil moisture may change the thermodynamics, hydrology, and erosion rate of surface soils, and facilitate transport of materials that had previously been stable. These changes to the soil active layer could significantly modify permafrost and ground ice stability within the Dry Valleys. The PIs seek to investigate these changes to address two competing hypotheses: that the source of water to these ?wet spots? is ground ice melt and that the source of this water is snowmelt. The PIs will document the spatiotemporal dynamics of these wet areas using high frequency remote sensing data from Quickbird and Wordview satellites to document the occurrence, dimensions, and growth of wet spots during the 2010-Â11 and 2011-Â12 austral summers. They will test their hypotheses by determining whether wet spots recur in the same locations in each season, and they will compare present to past distribution using archived imagery. They will also determine whether spatial snow accumulation patterns and temporal ablation patterns are coincident with wet spot formation. <br/><br/>Broader impacts: <br/>One graduate student will be trained on this project. Findings will be reported at scientific meetings and published in peer reviewed journals. They will also develop a teaching module on remote sensing applications to hydrology for the Modular Curriculum for Hydrologic Advancement and an innovative prototype project designed to leverage public participation in mapping wet spots and snow patches across the Dry Valleys through the use of social media and mobile computing applications.
Whales play a central role in the ecology and biogeochemistry of the Southern Ocean. However, little is known regarding their distribution and behavior, in part because of challenges associated with studying these organisms from large research vessels. This research will take advantage of the unique opportunity presented by the 2012-2013 test run of the smaller, more mobile R/V Point Sur. This work will use the Point Sur to investigate humpback whales in the waters studied by the Palmer Long Term Ecological Research (LTER) Station off the Western Antarctic Peninsula (WAP). Employing a combination of long-term satellite-linked tags and short-term suction cup tags, researchers will investigate the distribution, abundance and foraging behaviors of whales in this region. Whale biogeography will then be related to quantitative surveys of krill, their primary food source. Hypotheses regarding whale distribution and foraging strategies as well as physical oceanographic features will be tested. The WAP is undergoing some of the most dramatic warming on the planet, and a better understanding of the ecology of top predators is central to developing an understanding of the impacts of this change. Results will be widely disseminated through publications as well as through presentations at national and international meetings. In addition, raw data will be made available through open-access databases. Finally, this work will be coordinated with the extensive infrastructure of the Palmer LTER site, enabling outreach and educational activities.
Intellectual Merit: <br/>The PIs proposed a provenance study of glacial deposits in the Ross Embayment that will provide a broad scale geochronologic survey of detrital minerals in till to help characterize bedrock beneath the East Antarctic ice sheet and constrain Antarctica?s glacial history. This project capitalizes on previous investments in field sampling. Analytical tools applied to single mineral grains extracted from existing collections of glacial till will generate ?fingerprints? of East Antarctic outlet glaciers and West Antarctic till to refine paleo-ice flow models for the Ross Embayment during the last glacial maximum, older records from ANDRILL cores, and to assess IRD sources in the Southern Ocean. New provenance tracers will include a suite of geochronological methods that together provide greater insights into the orogenic and erosional history the region. This project will include U/Pb of detrital zircons, (U-Th)/He on a subset of the U/Pb dated zircons, as well as Ar-Ar of detrital hornblende, mica and feldspars. <br/><br/>Broader impacts: <br/>This research will train one M.S. student at IUPUI, a Ph.D. student at Columbia, and several undergraduates at both institutions. Graduate students involved in the project will be involved in mentoring undergraduate researchers. Incorporation of research discoveries will be brought into the classroom by providing concrete examples and exercises at the appropriate level. Licht and Columbia graduate student E. Pierce are developing outreach projects with local secondary school teachers to investigate the provenance of glacial materials in their local areas. The research will have broad applicability to many fields.
The research will explore the genetics, diversity, and biogeography of Antarctic marine benthic invertebrates, seeking to overturn the widely accepted suggestion that benthic fauna do not constitute a large, panmictic population. The investigators will sample adults and larvae from undersampled regions of West Antarctica that, combined with existing samples, will provide significant coverage of the western hemisphere of the Southern Ocean. The objectives are: 1) To assess the degree of genetic connectivity (or isolation) of benthic invertebrate species in the Western Antarctic using high-resolution genetic markers. 2) To begin exploring planktonic larvae spatial and bathymetric distributions for benthic shelf invertebrates in the Bellinghausen, Amundsen and Ross Seas. 3) To continue to develop a Marine Antarctic Genetic Inventory (MAGI) that relates larval and adult forms via DNA barcoding. Broader impacts include traditional forms of training (postdocs, graduate studentships, undergraduate research experiences) and lectures to K-12 groups.
Intellectual Merit: The Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) is a study of ocean mixing in the Antarctic Circumpolar Current (ACC) which runs west to east all around the continent of Antarctica, south of the other continents. This current system is somewhat of a barrier to transport of heat, carbon dioxide and other important ocean constituents between the far south and the rest of the ocean, and mixing processes play an important role in those transports. DIMES is a multi-investigator cooperative project, led by physical oceanographers in the U.S. and in the U.K. A passive tracer and an array of sub-surface floats were deployed early in 2009 more than 2000 km west of Drake Passage on a surface of constant density about 1500 m deep between the Sub Antarctic Front and the Polar Front of the ACC. In early 2010 a U.S. led research cruise sampled the tracer, turbulence levels, and the velocity and density profiles that govern the generation of that turbulence, and additional U.K. led research cruises in 2011 and 2012 continue this sampling as the tracer has made its way through Drake Passage, into the Scotia Sea, and over the North Scotia Ridge, a track of more than 3000 km. The initial results show that diapycnal, i.e., vertical, mixing west of Drake Passage where the bottom is relatively smooth is no larger than in most other regions of the open ocean. In contrast, there are strong velocity shears and intense turbulence levels over the rough topography in Drake Passage and diapycnal diffusivity of the tracer more than 10 times larger in Drake Passage and to the east than west of Drake Passage.<br/><br/>The DIMES field program continues with the U.S. team collecting new velocity and turbulence data in the Scotia Sea. It is anticipated that the tracer will continue passing through the Scotia Sea until at least early 2014. The U.K. partners have scheduled sampling of the tracer on cruises at the North Scotia Ridge and in the eastern and central Scotia Sea in early 2013 and early 2014. The current project will continue the time series of the tracer at Drake Passage on two more U.S. led cruises, in late 2012 and late 2013. Trajectories through the Scotia Sea estimated from the tracer observations, from neutrally buoyant floats, and from numerical models will be used to accurately estimate mixing rates of the tracer and to locate where the mixing is concentrated. During the 2013 cruise the velocity and turbulence fields along high-resolution transects along the ACC and across the ridges of Drake Passage will be measured to see how far downstream of the ridges the mixing is enhanced, and to test the hypothesis that mixing is enhanced by breaking lee waves generated by flow over the rough topography.<br/><br/>Broader Impacts: DIMES (see web site at http://dimes.ucsd.edu) involves many graduate students and post-doctoral researchers. Two graduate students, who would become expert in ocean turbulence and the processes generating it, will continue be trained on this project. The work in DIMES is ultimately motivated by the need to understand the overturning circulation of the global ocean. This circulation governs the transport and storage of heat and carbon dioxide within the huge oceanic reservoir, and thus plays a major role in regulating the earth?s climate. Understanding the circulation and how it changes in reaction to external forces is necessary to the understanding of past climate change and of how climate might change in the future, and is therefore of great importance to human well-being. The data collected and analyzed by the DIMES project will be assembled and made publicly available at the end of the project.<br/><br/>The DIMES project is a process experiment sponsored by the U.S. CLIVAR (Climate variability and predictability) program.
Intellectual Merit: <br/>The PI proposes to utilize computer models used by hydrogeologists to establish the fate and transport of contamination and determine the extent of drilling fluid contamination in the ANDRILL SMS core. For these models, previously collected logs of lithology, porosity, fracture density, fracture type, fracture orientation, drilling fluid loss, drilling fluid characteristics and temperature will be used as input parameters. In addition, biodegradation and sorption constants for the drilling fluid will be determined and incorporated into the models. Samples of drilling fluids used during coring as well as the return fluids were collected at the drill site using standard microbiological sampling techniques. Fluids will be tested at in situ temperatures under aerobic and anaerobic conditions to determine biodegradation constants. Sorption will be determined between the drilling fluids and core samples using standard isotherm methods. Geochemical and microbial fingerprints of the fluids and the changes during biodegradation will determine the potential impact of the drilling fluids on the isolated microbial communities and the geochemistry within various subsurface lithologic units beneath the southern McMurdo Sound in Antarctica. The results of this study could potentially provide guidelines on developing less detrimental methods for future exploration, if deemed necessary through this research.<br/><br/>Broader impacts: <br/>This proposed project will train a graduate student. The methods developed for analyses of samples in this project will serve as a guide for future studies of similar interest and will improve the understanding of ecological impacts of geologic drilling in Antarctica. The results of this study will be used as a reference for comparison with future studies examining newly developed, and improved, sample collection methods in future exploratory drilling projects in pristine environments. The PI is new to Antarctic research.
This five-year project seeks to characterize decadal scale changes in penguin and seabird populations on the Antarctic Peninsula, and to identify the factors driving these long-term changes. Two interconnected research activities are proposed: 1. Continued, long-term monitoring and censusing of penguin and seabird populations at >117 sites throughout the Antarctic Peninsula via opportunistic ship-based data collection. 2. Synthesis and quantitative analyses of datasets detailing long-term changes in five penguin and seabird species from diverse sites throughout the Antarctic Peninsula. When complete, the penguin/seabird database will incorporate data from the Antarctic Site Inventory (ASI), the CCAMLR database, the US AMLR database, the LTER database from Palmer Station, data from British and Argentine researchers, historic census data compiled by the Scientific Committee on Antarctic Research (SCAR), and, when possible, additional privately held datasets. Additional data for temperature change, sea ice coverage, the seasonal timing and intensity of human visitation, and other factors have been gathered and will be analyzed together with population trajectories within a spatially explicit framework. The research will include hierarchical statistical analyses to characterize the long-term population dynamics of several key polar species across multiple spatial scales (sites, regions, and the Peninsula). Analyses also will focus on specific subsets of the overall database to contrast visitor impacts on paired colonies, sites, and regions that share similar environmental conditions but differ in the intensity of tourism. <br/><br/>The Broader Impacts include (1) research training and first-time Antarctic experiences for a postdoctoral researcher and several graduate students, all of whom will then be better positioned to bring their expertise in spatial and/or quantitative/theoretical ecology to bear on questions in polar research; (2) assembly and analysis of a large, multi-season database of penguin and seabird time series from the Antarctic Peninsula that will be publicly available, (3) assistance in distinguishing the impacts of tourism versus climate change on seabird populations. Under the Environmental Protocol to the Antarctic Treaty, Treaty Parties are charged with regular and effective monitoring to assess the impacts of human activities. This project will uniquely assist Parties in fulfilling this mandate.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>Two models have been proposed to describe controls over microbial biogeography. One model proposes that microbes are ubiquitously distributed across the global environment, and that environmental conditions select for taxa physiologically adapted to local physical conditions. An alternative model predicts that dispersal is the important limitation to the distribution of microorganisms and that spatial heterogeneity of microbial communities is a result of both dispersal and local environmental limitations. According to both models, spatial heterogeneity of microbial communities may be especially pronounced in extreme ecosystems where the environmental selection for organisms with suitable physiology is most strongly manifest. We propose that Antarctic terrestrial environments are ideal places to examine microbial biogeography for 3 reasons: 1) the pristine nature and remoteness of Antarctica minimizes the prevalence of exotic species dispersed through human vectors; 2) the extreme conditions of Antarctic environments provide a strong environmental filter which limits the establishment of non-indigenous taxa; and 3) extreme heterogeneity in the terrestrial environment provides natural gradients of soil conditions (temperature, water and nutrient availability). In the proposed research we will investigate the influence of snow on the composition and spatial distribution of soil microbial communities and linked biogeochemical cycling in the McMurdo Dry Valleys. We will conduct fieldwork at the landscape scale (repeated remote sensing to characterize snow distribution), at the valley and patch scales (quantify snow patch ablation, microbial communities and biogeochemical cycling in subnivian soils). We hypothesize that snow patches play an important role in structuring the spatial distribution of soil microbial communities and their associated ecosystem functioning because of the physical and hydrological influences that snow patches have on the soil environment. The research will contribute to greater public awareness of the importance of polar research to fundamental questions of biology, ecology and hydrology through direct linkages with International Antarctic Institute public outreach activities, including dissemination of web-based learning units on environmental science and microbiology, targeted as resources for secondary and post-secondary educators. Three graduate students, one postdoctoral scholar and multiple undergraduates will participate in the research activities.
Hofmann, Eileen; Dinniman, Michael; Klinck, John M.
No dataset link provided
Abstract<br/><br/>This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>The Ross Sea is a highly productive area within the Southern Ocean, but it experiences substantial variability in both physical (temperature, ice concentrations, salinity, winds, and current velocities) and biogeochemical (chlorophyll, productivity, micronutrients, higher trophic level standing stocks, gases, etc.) conditions. Understanding the temporal and spatial oceanographic variations in physical forcing is essential to understanding the ecological functioning within the Ross Sea. There are a number of models of the physical oceanography of the Ross Sea that characterize the observed circulation. Unfortunately, data on the appropriate time scales (daily, monthly, seasonal, and interannual) to completely evaluate those models are lacking. The proposed research is a demonstration project to characterize the physical and biological oceanography of the southern Ross Sea using newly developed Glider technology to sample the region continuously through the growing season, to collect temperature, salinity, fluorescence, oxygen and optical transmission data. These field data will be used to assist in evaluation of an eddy-resolving ROMS-based coupled circulation-biological model, and, along with satellite ocean color information, will be assimilated into an ecosystem model. Data assimilation techniques will reduce the model uncertainties of the circulation and food webs of the region. The intellectual merit of this effort arises from the combination of field-based investigations using a novel technology (one that is far more cost-effective than ship-based studies) with state-of-the-art biological-physical models and advanced data assimilation techniques. The research will provide new insights into the complex oceanographic phenomena of the Antarctic continental shelves and is a novel method of continuing the studies of the southern Ross Sea. Broader impacts of the proposed research include training of graduate and undergraduate students and partnership with several ongoing outreach programs dealing with scientific research in the Southern Ocean. At least 2 graduate students will be supported by this research, and it will be a critical component of a variety of outreach programs in Virginia, including a High School Marine Science Day, Boy and Girl Scout education, and middle school curriculum improvement. The investigators also will create a web site to foster immediate release of the data collected by the glider, and seek a linkage with schools at various levels (middle, high school and Universities) that potentially could incorporate the data into classroom activities
Abstract <br/>This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). <br/><br/>Marine mammals of the Southern Ocean have evolved diverse life history patterns and foraging strategies to accommodate extreme fluctuations in the physical and biological environment. In light of ongoing climate change and the dramatic shifts in the extent and persistence of sea ice in the Ross Sea, it is critical to understand how Weddell seals, Leptonychotes weddellii, a key apex predator, select and utilize foraging habitats. Recent advances in satellite-linked animal-borne conductivity, temperature and depth (CTD) tags make it possible to simultaneously collect data on seal locations, their diving patterns, and the temperature and salinity profiles of the water columns they utilize. In other ecosystems, such data have revealed that marine predators selectively forage in areas where currents and fronts serve to locally concentrate prey resources, and that these conditions are required to sustain populations. Weddell seals will be studied in McMurdo Sound and at Terra Nova Bay, Ross Sea and will provide the first new data on Weddell seal winter diving behavior and habitat use in almost two decades. The relationship between an animal's diving behavior and physical habitat has enormous potential to enhance monitoring studies and to provide insight into how changes in ice conditions (due either to warming or the impact of large icebergs, such as B15) might impact individual time budgets and foraging success. The second thrust of this project is to use the profiles obtained from CTD seal tags to model the physical oceanography of this region. Current mathematical models of physical oceanographic processes in the Southern Ocean are directed at better understanding the role that it plays in global climate processes, and the linkages between physical and biological oceanographic processes. However, these efforts are limited by the scarcity of oceanographic data at high latitudes in the winter months; CTD tags deployed on animals will collect data at sufficient spatial and temporal resolution to improve data density. The project will contribute to two IPY endorsed initiatives: MEOP (Marine Mammals as Explorers of the Ocean Pole to Pole) and CAML (Census of Antarctic Marine Life). In addition, the highly visual nature of the data and analysis lends itself to public and educational display and outreach, particularly as they relate to global climate change, and we have collaborations with undergraduate and graduate training programs, the Seymour Marine Discovery Center, and the ARMADA program to foster these broader impacts.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). <br/><br/>Most organisms meet their carbon and energy needs using photosynthesis (phototrophy) or ingestion/assimilation of organic substances (heterotrophy). However, a nutritional strategy that combines phototrophy and heterotrophy - mixotrophy - is geographically and taxonomically widespread in aquatic systems. While the presence of mixotrophs in the Southern Ocean is known only recently, preliminary evidence indicates a significant role in Southern Ocean food webs. Recent work on Southern Ocean dinoflagellate, Kleptodinium, suggests that it sequesters functional chloroplasts of the bloom-forming haptophyte, Phaeocystis antarctica. This dinoflagellate is abundant in the Ross Sea, has been reported elsewhere in the Southern Ocean, and may have a circumpolar distribution. By combining nutritional modes. mixotrophy may offer competitive advantages over pure autotrophs and heterotrophs. <br/><br/>The goals of this project are to understand the importance of alternative nutritional strategies for Antarctic species that combine phototrophic and phagotrophic processes in the same organism. The research will combine field investigations of plankton and ice communities in the Southern Ocean with laboratory experiments on Kleptodinium and recently identified mixotrophs from our Antarctic culture collections. The research will address: 1) the relative contributions of phototrophy and phagotrophy in Antarctic mixotrophs; 2) the nature of the relationship between Kleptodinium and its kleptoplastids; 3) the distributions and abundances of mixotrophs and Kleptodinium in the Southern Ocean during austral spring/summer; and 4) the impacts of mixotrophs and Kleptodinium on prey populations, the factors influencing these behaviors and the physiological conditions of these groups in their natural environment. The project will contribute to the maintenance of a culture collection of heterotrophic, phototrophic and mixotrophic Antarctic protists that are available to the scientific community, and it will train graduate and undergraduate students at Temple University. Research findings and activities will be summarized for non-scientific audiences through the PIs' websites and through other public forums, and will involve middle school teachers via collaboration with COSEE-New England.
Despite being an essential physiological component of homeotherm life in polar regions, little is known about the energetic requirements for thermoregulation in either air or water for high- latitude seals. In a joint field and modeling study, the principal investigators will quantify these costs for the Weddell seal under both ambient air and water conditions. The field research will include innovative heat flux, digestive and locomotor cost telemetry on 40 free-ranging seals combined with assessments of animal health (morphometrics, hematology and clinical chemistry panels), quantity (ultrasound) and quality (tissue biopsy) of blubber insulation, and determination of surface skin temperature patterns (infrared thermography). Field-collected data will be combined with an established individual based computational energetics model to define cost-added thresholds in body condition for different body masses. This study will fill a major knowledge gap by providing data essential to modeling all aspects of pinniped life history, in particular for ice seals. Such parameterization of energetic cost components will be essential for the accurate modeling of responses by pinnipeds to environmental variance, including direct and indirect effects driven by climate change. The study also will provide extensive opportunities in polar field work, animal telemetry, biochemical analyses and computational modeling for up to three undergraduate students and one post-doctoral researcher. Integrated education and outreach efforts will educate the public (K-12 through adult) on the importance of quantifying energetic costs of thermoregulation for marine mammals and the need to understand responses of species to environmental variance. This effort will include a custom-built, interactive hands-on mobile exhibit, and development of content for an Ocean Today kiosk.
Stone/0838818 <br/><br/>This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). <br/><br/>This award supports a project to study the former thickness and retreat history of Shackleton and Beardmore Glaciers which flow through the Transantarctic Mountains (TAMs) into the southern Ross Sea. Lateral moraine deposits along the lower reaches of these major outlet glaciers will be mapped and dated and the results will help to date the LGM and constrain the thickness of ice where it left the Transantarctic Mountains and flowed into the Ross Sea. The intellectual merit of the project is that the results will allow scientists to distinguish between models of ice retreat, which have important implications for former ice configuration and dynamics, and to constrain the contribution from Ross Sea deglaciation to global sea level through the late Holocene. In addition, this will make a significant contribution to a better understanding of the magnitude and timing of postglacial sea-level change and the potential contribution of Antarctica to sea-level rise in future. The broader impacts of the project are that the work will help quantify changes in grounded ice volume since the LGM, improve understanding of the ice dynamics responsible, and examine their implications for future sea level change. The project will train future scientists through participation of two graduate students and undergraduates who will develop self-contained research projects. As in previous Antarctic projects, there will be interaction with K-12 students through classroom visits, web-based expedition journals, letters from the field, and discussions with teachers and will allow the project to be shared with a wide audience. This award has field work in Antarctica.
Intellectual Merit: <br/>Mt. Erebus is one of only a handful of volcanoes worldwide that have lava lakes with readily observable and nearly continuous Strombolian explosive activity. Erebus is also unique in having a permanent convecting lava lake of anorthoclase phonolite magma. Over the years significant infrastructure has been established at the summit of Mt. Erebus as part of the Mount Erebus Volcano Observatory (MEVO), which serves as a natural laboratory to study a wide range of volcanic processes, especially magma degassing associated with an open convecting magma conduit. The PI proposes to continue operating MEVO for a further five years. The fundamental fundamental research objectives are: to understand diffuse flank degassing by using distributed temperature sensing and gas measurements in ice caves, to understand conduit processes, and to examine the environmental impact of volcanic emissions from Erebus on atmospheric and cryospheric environments. To examine conduit processes the PI will make simultaneous observations with video records, thermal imaging, measurements of gas emission rates and gas compositions, seismic, and infrasound data.<br/><br/>Broader impacts: <br/>An important aspect of Erebus research is the education and training of students. Both graduate and undergraduate students will have the opportunity to work on MEVO data and deploy to the field site. In addition, this proposal will support a middle or high school science teacher for two field seasons. The PI will also continue working with various media organizations and filmmakers.
The west Antarctic Peninsula is warming rapidly, and continuing changes in the thermal regime will likely result in severe consequences for marine fauna, including potential extinction of strongly adapted stenotherms, and invasions from neighboring faunas. Initial impacts of climate change may result in changes in connectivity among populations of the same species. These changes may will be undetectable by direct observation, but may be assessed via genetic connectivity, i.e. differences in allele or haplotype frequencies among populations can be used to infer levels of gene flow. The proposed research will explore the role that the Scotia Arc plays in connecting populations from South America to Antarctica, a corridor identified as a likely entry route for invaders into Antarctica. It also will examine the way in which cryptic species may confound our knowledge of broad-scale distributions, and in doing so, make contributions towards understanding biodiversity and testing the paradigm of circumpolarity in Antarctica. The principal investigator will to collect multi-locus genetic data across 'species' from a broad suite of benthic marine invertebrate phyla, from multiple locations, in order to address hypotheses regarding speciation and connectivity, to estimate demographic population changes, and to identify the underlying processes that drive observed phylogeographic patterns. Comparative phylogeography is a particularly valuable approach because it enables the identification of long-term barriers and refugia common to groups of species and is consequently highly relevant to conservation planning. Moreover, this work will form a valuable baseline for detecting future changes in connectivity. The results of the research will be disseminated through peer-reviewed publications and presentations at conferences. In addition, the project will support the interdisciplinary training of a female graduate student, two undergraduate students, and host additional summer students through the STARS program at SIO, which helps minority students prepare for graduate school. This project will integrate research and education through conducting an interdisciplinary workshop that brings together Earth Science and Biology high school teachers. This workshop aims to assist teachers derive their own curricula uniting plate tectonics, ocean history and evolution, supporting a new high school earth sciences program. Information generated by this project will also directly feed into international efforts to design a series of Marine Protected Areas (MPAs) in Antarctica.
Since 1990, Palmer LTER (PAL) research has been guided by the hypothesis that variability in the polar marine ecosystem is mechanistically coupled to changes in the annual advance, retreat and spatial extent of sea ice. Since that time, the hypothesis has been modified to incorporate climate migration, i.e. the displacement of a cold, dry polar climate by a warm, moist climate regime in the northern component of the PAL region, producing fundamental changes in food web structure and elemental cycling. The observed northern changes are affecting all trophic levels and elemental cycling, and the primary mechanism of change involves match-mismatch dynamics. The proposed research builds on previous findings, with a new emphasis on process studies and modeling to elucidate the mechanistic links between teleconnections, climate change, physical oceanographic forcing and ecosystem dynamics. The proposed research will examine the hypothesis that regional warming and sea ice decline associated with historical and on-going climate migration in the northern part of the study area have altered key phenological relationships, leading to changes in species distributions, increasing trophic mismatches and changes in habitat, food availability, ecosystem dynamics and biogeochemical cycling. Through targeted process studies linked to numerical model simulations, the research also will test the hypothesis that deep cross-shelf canyons characterizing the core study region are focal areas for ecosystem processes that result in predictable, elevated food resources for top-predators. The effort includes the addition of 3 new PIs: a zooplankton ecologist with expertise in biogeochemical fluxes, a phytoplankton ecologist focusing on bio-optics and autonomous observations using gliders, and a numerical simulation modeler specializing in coupled global models of ocean circulation, plankton ecology and biogeochemical cycles. The program will add trace metal sampling and analysis, moored physical oceanographic sensors, a moored sediment trap in the south, drifting sediment traps and stable carbon (del 13C) and nitrogen (del 15N) isotope analyses. Missions lasting up to 45 days using gliders deployed before, during and after summer cruises will, along with moorings and satellite remote sensing of sea ice, ocean color, sea surface temperatures and wind fields, greatly extend the observational program in space and time. <br/><br/>Since its inception, PAL has been a leader in Information Management to enable knowledge-building within and beyond the Antarctic, oceanographic and LTER communities. PAL has designed and deployed a new information infrastructure with a relational database architecture to facilitate data distribution and sharing. The Education and Outreach program capitalizes on the public's fascination with Antarctica to promote scientific literacy from kindergarten students to adult citizens concerned with climate change and environmental sustainability. Through communicating results to the public and working with scientific assessment bodies (e.g., IPCC) and Antarctic Treaty parties to protect Earth's last frontier, PAL researchers contribute to the national scientific agenda and the greater public benefit.
Several aspect of the seasonal melting and reformation cycle of Antarctic sea ice appear to be divergent from those occurring in the Arctic. This is most clearly demonstrated by the dramatic diminishing extent and thinning of the Arctic sea ice, to be contrasted to the changes in Antarctic sea-ice extent, which recently (decadaly) shows small increases. Current climate models do not resolve this discrepancy which likely results from both a lack of relevant observational sea-ice data in the Antarctic, along with inadequacies in the physical parameterization of sea-ice properties in climate models.<br/><br/>Researchers will take advantage of the cruise track of the I/B Oden during transit through the Antarctic sea-ice zones in the region of the Bellingshausen, Amundsen and Ross (BAR) seas on a cruise to McMurdo Station. Because of its remoteness and inaccessibility, the BAR region is of considerable scientific interest as being one of the last under described and perhaps unexploited marine ecosystems left on the planet .<br/><br/>A series of on station and underway observations of sea ice properties will be undertaken, thematically linked to broader questions of summer ice survival and baseline physical properties (e.g. estimates of heat and salt fluxes). In situ spatiotemporal variability of sea-ice cover extent, thickness and snow cover depths will be observed.
The auroral electrojet index (AE) is used as an indicator of geomagnetic activity at high latitudes representing the strength of auroral electrojet currents in the Northern polar ionosphere. A similar AE index for the Southern hemisphere is not available due to lack of complete coverage the Southern auroral zone (half of which extends over the ocean) with continuous magnetometer observations. While in general global auroral phenomena are expected to be conjugate, differences have been observed in the conjugate observations from the ground and from the Earth's satellites. These differences indicate a need for an equivalent Southern auroral geomagnetic activity index. The goal of this award is to create the Southern AE (SAE) index that would accurately reflect auroral activity in that hemisphere. With this index, it would be possible to investigate the similarities and the cause of differences between the SAE and "standard" AE index from the Northern hemisphere. It would also make it possible to identify when the SAE does not provide a reliable calculation of the Southern hemisphere activity, and to determine when it is statistically beneficial to consider the SAE index in addition to the standard AE while analyzing geospace data from the Northern and Southern polar regions. The study will address these questions by creating the SAE index and its "near-conjugate" NAE index from collected Antarctic magnetometer data, and will analyze variations in the cross-correlation of these indices and their differences as a function of geomagnetic activity, season, Universal Time, Magnetic Local Time, and interplanetary magnetic field and solar wind plasma parameters. The broader impact resulting from the proposed effort is in its importance to the worldwide geospace scientific community that currently uses only the standard AE index in a variety of geospace models as necessary input.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The high elevations of East Antarctica are critical in localizing the initial Cenozoic glaciation and stabilizing it with respect to melting during warm interglacials. However, the geological history for this region and the geophysical mechanism for maintaining the highlands are poorly understood. In 2007-2009, an array of 24 broadband seismographs (named GAMSEIS) was installed across the Gamburtsev Mountains area of the East Antarctic Plateau as part of the Antarctica?s Gamburtsev Province (AGAP) International Polar Year project. The IPY AGAP/GAMSEIS program included plans by other international partners to install seismographs at locations along the flanks of the Gamburtsev Mountains and in other East Antarctic regions. The proposed project will continue operating six of the deployed AGAP/GAMSEIS stations for two more years together with two new broadband seismic stations added to broaden the geographic scope of the array. Most stations will be located at the existing U.S. Autonomous Geophysical Observatories and the USAP fuel cache locations in order to minimize logistical support. This array, combined with seismographs deployed by China and Japan (and possibly Australia, France, and Italy in near future) will provide a sparse but large-scale network of seismometers for the longer-term studies of the crustal and upper mantle structures underneath the East Antarctic Plateau. Continued reliance on students provides a broader impact to this proposed research and firmly grounds this effort in its educational mission.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The investigators will examine competing hypotheses for the mechanism of extension and creation of the Transantarctic Mountains, and evolution of the thermal regimes of rifted West Antarctica and stable East Antarctica using magnetotelluric (MT) profiles. Surrounded almost entirely by ocean ridges, Antarctica is a special tectonic situation because of the need to make accommodation space for rifting in the Transantarctic region. In the MT method, temporal variations in the Earth's natural electromagnetic field are used as source fields to probe the electrical resistivity structure in the depth range of 1 to 200 km, or more. Geophysical methods, such as MT, are appropriate in Antarctica because of the predominance of thick ice cover over most of the Continent and the difficult operating environment. The proposed effort will consist of approximately 50 sites over a distance approaching 500 km with a 10 km average spacing, oriented normal to the Transantarctic Mountains (TAM), in the Beardmore glacier area. High quality MT soundings will be collected over thick ice sheets using a custom electrode preamp design, updated from previous Antarctic projects. Data acquisition will take place over two field seasons. The primary goals are three-fold: to establish the location of the deeper tectonic transition between East and West Antarctica that may be offset from the physiographic transition at the surface, using deep resistivity structure distinguish between modes of extensional upwelling and magmatism that may be vertically non-uniform, depth and magnitude of quasi-layered deep crustal low resistivity, particularly below West Antarctica, will be used to estimate crustal heat flux into the ice sheet base.
Antarctic polynyas are the ice free zones often persisting in continental sea ice. Characterization of the lower atmosphere properties, air-sea surface heat fluxes and corresponding ocean depth profiles of Antarctic polynyas, especially during strong wind events, is needed for a more detailed understanding of the role of polynya in the production of latent-heat type sea ice and the formation, through brine rejection, of dense ocean bottom waters. <br/><br/>Broader impacts: A key technological innovation, the use of instrumented uninhabited aircraft systems (UAS), will be employed to enable the persistent and safe observation of the interaction of light and strong katabatic wind fields with the Terra Nova Bay (Victoria Land, Antarctica) polynya waters during late winter and early summer time frames. The use of UAS observational platforms on the continent to date has to date been modest, but demonstration of their versatility and effectiveness in surveying and observing mode is a welcome development. The projects use of UAS platforms by University of Colorado and LDEO (Columbia) researchers is both high risk, and potentially transformative for the systematic data measurement tasks that many Antarctic science applications increasingly require.
0538674<br/>Matsuoka<br/>This award supports a project to evaluate radio-echo intensities in the available SOAR ice-penetrating radar data along grids covering Lake Vostok, and along four regional tracks from Ridge B toward the lake. The project has two objectives; first, it will examine the upper surface of the lake and reflectors hypothesized to be a boundary between the meteoric and accreted ice. They will provide crucial knowledge on the dynamic evolution of the lake. Second, this project will examine a poorly understood echo-free zone within the deep ice in central East Antarctica. This zone may consist of distorted stagnant ice, while its upper boundary may be a shear zone. The SOAR radar data provide a unique resource to examine spatiotemporal water circulation patterns that should be understood in order to select the best direct-sampling strategy to the lake. The Vostok ice core provides a unique opportunity to do this work. First, the path effects, i.e. propagation loss and birefringence, will be derived at the ice-core site using ice temperature, chemistry, and fabric data. Second, lateral variations of the propagation loss will be estimated by tracking chemistry associated with radar-detected isochronous layers, and by inferring temperatures from an ice-flow model that can replicate those layers. Ice-fabric patterns will be inferred from anisotropy in the reflectivity at about 100 radar-track cross-over sites. In terms of broader impacts, a graduate student will be trained to interpret the radar data in the light of radar theory and glaciological context of Lake Vostok and summer workshops for K-12 teachers will be provided in Seattle and New York. This project will contribute to ongoing efforts to study Lake Vostok and will complement the site selection for a North Vostok ice core, which has been proposed by Russia and France as an IPY program.
This award will support the participation of US scientists in an international planning workshop devoted to discussions of how to best facilitate and coordinate international efforts for terrestrial system studies at the McMurdo Dry Valleys of Antarctica. To date, various aspects of the different Dry Valley landscape features (lakes, soils, glaciers, streams) and their biota have been studied most intensively by US and New Zealand scientists, but these efforts could significantly improve their explanatory power if they were coordinated so as to reduce redundancy, decrease environmental degradation and, most importantly, produce comparable datasets. Additionally, many of the present environmental management programs are based on the past baseline composition and location of biotic communities. As these communities become rearranged across the valleys in the future there is interest in assessing whether today's management plans are adequate. To efficiently move these research programs forward for the McMurdo Dry Valleys requires a coordinated, interdisciplinary, long-term data monitoring and observation network. <br/><br/>The ultimate objectives of the workshop are to: i) identify the optimal, complementary suites of measurements required to assess and address key processes associated with environmental change in Dry Valley ecosystems; ii) develop standards and protocols for gathering the most critical biotic and abiotic measurements associated with the key processes driving environmental change; iii) generate a draft data coordination and development plan that will maximize the utility of these data; iv) assess the effectiveness of current McMurdo Dry Valley ASMA (Antarctic Special Management Area) environmental protection guidelines.
Catania 0739654<br/><br/>This award supports a project to study the Amundsen Sea drainage system and improve understanding of the impact of recent glaciological changes as an aid to predicting how this region will change in the future. The intellectual merit of the work is that the Amundsen Sea drainage system has been a recent focus for glaciological research because of rapid changes occurring there as a result of grounding line retreat. The work will focus on the regions of flow transition and will map the internal stratigraphy of the ice sheet across the Thwaites Glacier shear margins and use the age and geometry of radar-detected internal layers to interpret ice flow history. Thwaites Glacier (one of the main pathways for ice drainage in the region) has recently widened and may continue to do so in the near future. Thwaites Glacier may be particularly vulnerable to grounding line retreat because it lacks a well-defined subglacial channel. The subglacial environment exerts strong control on ice flow and flow history will be mapped in the context of bed topography and bed reflectivity. The plan is to use existing ice-penetrating radar data and coordinate with planned upcoming surveys to reduce logistical costs. The work proposed here will take three years to complete but no additional fieldwork in Antarctica is required. More detailed ground-based geophysical (radar and seismic) experiments will be needed at key locations to achieve our overall goal and the work proposed here will aid in identifying those regions. The broader impacts of the project are that it will initiate a new collaboration among radar communities within the US including those that are on the forefront of radar systems engineering and those that are actively involved in radar-derived internal layer and bed analysis. The project will also provide support for a postdoctoral researcher and a graduate student, thus giving them exposure to a variety of methodologies and scientific issues. Finally, there are plans to further develop the "Wired Antarctica" website designed by Ginny Catania with the help of a student-teacher. This will allow for the existing lesson plans to be updated to Texas State standards so that they can be used more broadly within state middle and high schools.
This award supports a project to strengthen collaborations between the various research groups working on iceberg calving. Relatively little is known about the calving process, especially the physics that governs the initiation and propagation of fractures within the ice. This knowledge gap exists in part because of the diverse range in spatial and temporal scales associated with calving (ranging from less than one meter to over a hundred kilometers in length scale). It is becoming increasingly clear that to predict the future behavior of the Antarctic Ice Sheet and its contribution to sea level rise, it is necessary to improve our understanding of iceberg calving processes. Further challenges stem from difficulties in monitoring and quantifying short-time and spatial-scale processes associated with ice fracture, including increased fracturing events in ice shelves or outlet glaciers that may be a precursor to disintegration, retreat or increased calving rates. Coupled, these fundamental problems currently prohibit the inclusion of iceberg calving into numerical ice sheet models and hinder our ability to accurately forecast changes in sea level in response to climate change. Seismic data from four markedly different environmental regimes forms the basis of the proposed research, and researchers most familiar with the datasets will perform all analyses. Extracting the similarities and differences across the full breadth of calving processes embodies the core of the proposed work, combining and improving methods previously developed by each group. Techniques derived from solid Earth seismology, including waveform cross-correlation and clustering will be applied to each data set allowing quantitative process comparisons on a significantly higher level than previously possible. This project will derive catalogues of glaciologically produced seismic events; the events will then be located and categorized based on their location, waveform and waveform spectra both within individual environments and between regions. The intellectual merit of this work is that it will lead to a better understanding of iceberg calving and the teleconnections between seismic events and other geophysical processes around the globe. The broader impacts of this work are that it relates directly to socio-environmental impacts of global change and sea level rise. Strong collaborations will form as a result of this research, including bolstered collaborations between the glacier and ice sheet communities, as well as the glaciology and seismology communities. Outreach and public dissemination of findings will be driven by SIO's Visualization Center, and Birch Aquarium, hosting presentations devoted to the role of the cryosphere in global change. Time-lapse movies of recent changes at Columbia Glacier will be used to engage potential young scientists. A program of presentations outside the university setting to at-risk and gifted youth will be continued. This study will also involve undergraduates in analyses and interpretation and presentation of the seismic data assembled. The work will also support two junior scientists who will be supported by this project.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>An interdisciplinary team of researchers will focus on describing the high productivity patchiness observed in phytoplankton blooms in the mid to late summer in the Ross Sea, Antarctica. Key hypotheses to be tested and extended are that intrusions of nutrient and micro nutrient (e.g. Fe) rich water masses of the Antarctic modified circumpolar deep water (CDW) up onto continental shelves act to control the biogeochemical response of a large area of the productive Ross Sea coastal region. It is believed that this enhanced productivity may be a significant contributing factor to the global carbon cycle. <br/><br/>A novel sampling strategy to be used to test the above hypotheses will employ a remotely controlled deep (1000m) glider (AUV) to locate and map CDW in near real time measuring C (conductivity), T (temperature), D (pressure) and apparent optical properties, and which will serve to direct further ship-based sampling. <br/><br/>The adaptive coordination of a polar research vessel with an AUV additionally provides an opportunity to engage in formal and informal education and public outreach on issues in polar research.
Areas of the Southern Ocean have spectacular blooms of phytoplankton during the austral spring and early summer. One of the dominant phytoplankton species, the haptophyte Phaeocystis antarctica, is a prolific producer of the organic sulfur compound dimethylsulfoniopropionate (DMSP) and Phaeocystis blooms are associated with some of the world's highest concentrations of DMSP and its volatile degradation product, dimethylsulfide (DMS). Sulfur, in the form of DMS, is transferred from the oceans to the atmosphere and can affect the chemistry of precipitation and influence cloud properties and possibly climate. DMSP and DMS are also quantitatively significant components of the carbon, sulfur and energy flows in many marine food webs, although very little information is available on these processes in high latitude systems. <br/><br/>This project will study how solar radiation and iron cycling affect DMSP and DMS production by phytoplankton, and the subsequent utilization of these labile forms of organic matter by the microbial food web. Four interrelated hypotheses will be tested in field-based experiments and in situ observations: 1) solar radiation, including enhanced UV-B due to seasonal ozone depletion, plays an important role in determining the net ecosystem production of DMS in the Ross Sea; 2) development of shallow mixed layers promotes the accumulation of DMS in surface waters, because of enhanced exposure of plankton communities to high doses of solar radiation; 3) DMSP production and turnover represent a significant part of the carbon and sulfur flux through polar food webs; 4) bloom development and resulting nutrient depletion (e.g., iron) will result in high production rates of DMSP and high DMS concentrations and atmospheric fluxes. Results from this study will greatly improve understanding of the underlying mechanisms controlling DMSP and DMS concentrations in polar waters, thereby improving our ability to predict DMS fluxes to the atmosphere from this important climatic region. <br/><br/>Both Drs. Kieber and Kiene actively engage high school, undergraduate and graduate students in their research and are involved in formal programs that target underrepresented groups (NSF-REU and the American Chemical Society-SEED). This project will continue this type of educational outreach. The PIs also teach undergraduate and graduate courses and incorporation of research experiences into their classes will enrich student learning experiences.
This study will investigate how the Antarctic Slope Front and continental slope morphology determine the exchanges of mass, heat, and fresh water between the shelf and the deep ocean, in particular those leading to outflows of dense water into intermediate and deep layers of the adjacent basins and into the world ocean circulation <br/>While the importance to the global ocean circulation and climate of cold water masses originating in the Antarctic is unquestioned, the processes by which these water masses enter the deep ocean circulation are not. The primary goal of this work therefore is to identify the principal physical processes that govern the transfer of shelf-modified dense water into intermediate and deep layers of the adjacent deep ocean. At the same time, it seeks to understand the compensatory poleward flow of waters from the oceanic regime. The upper continental slope has been identified as the critical gateway for the exchange of shelf and deep ocean waters. Here the topography, velocity and density fields associated with the nearly ubiquitous front must strongly influence the advective and turbulent transfer of water properties between the shelf and oceanic regimes. The study has four specific objectives: [1] Determine the mean frontal structure and the principal scales of variability, and estimate the role of the front on cross-slope exchanges and mixing of adjacent water masses; [2] Determine the influence of slope topography and bathymetry on frontal location and outflow of dense Shelf Water; [3] Establish the role of frontal instabilities, benthic boundary layer transports, tides and other oscillatory processes on cross-slope advection and fluxes; and [4] Assess the effect of diapycnal mixing, lateral mixing identified through intrusions, and nonlinearities in the equation of state on the rate of descent and the fate of outflowing, near-freezing Shelf Water.
Areas of the Southern Ocean have spectacular blooms of phytoplankton during the austral spring and early summer. One of the dominant phytoplankton species, the haptophyte Phaeocystis antarctica, is a prolific producer of the organic sulfur compound dimethylsulfoniopropionate (DMSP) and Phaeocystis blooms are associated with some of the world's highest concentrations of DMSP and its volatile degradation product, dimethylsulfide (DMS). Sulfur, in the form of DMS, is transferred from the oceans to the atmosphere and can affect the chemistry of precipitation and influence cloud properties and possibly climate. DMSP and DMS are also quantitatively significant components of the carbon, sulfur and energy flows in many marine food webs, although very little information is available on these processes in high latitude systems. <br/><br/>This project will study how solar radiation and iron cycling affect DMSP and DMS production by phytoplankton, and the subsequent utilization of these labile forms of organic matter by the microbial food web. Four interrelated hypotheses will be tested in field-based experiments and in situ observations: 1) solar radiation, including enhanced UV-B due to seasonal ozone depletion, plays an important role in determining the net ecosystem production of DMS in the Ross Sea; 2) development of shallow mixed layers promotes the accumulation of DMS in surface waters, because of enhanced exposure of plankton communities to high doses of solar radiation; 3) DMSP production and turnover represent a significant part of the carbon and sulfur flux through polar food webs; 4) bloom development and resulting nutrient depletion (e.g., iron) will result in high production rates of DMSP and high DMS concentrations and atmospheric fluxes. Results from this study will greatly improve understanding of the underlying mechanisms controlling DMSP and DMS concentrations in polar waters, thereby improving our ability to predict DMS fluxes to the atmosphere from this important climatic region. <br/><br/>Both Drs. Kieber and Kiene actively engage high school, undergraduate and graduate students in their research and are involved in formal programs that target underrepresented groups (NSF-REU and the American Chemical Society-SEED). This project will continue this type of educational outreach. The PIs also teach undergraduate and graduate courses and incorporation of research experiences into their classes will enrich student learning experiences.
This project studies glaciovolcanic deposits at Minna Bluff in the western Ross Embayment of Antarctica. Its goal is to determine the history of the Ross Ice Shelf, which is fed by the major ice sheets from both East and West Antarctica. Apart from determining how these ice sheets waxed and waned during a period of dynamic climate change, glaciovolcanic sequences may constrain ice sheet parameters that are critical to numerical models such as thickness, hydrology, and basal thermal regime. This three-year study would map, analyze, and determine the age of key units using 40Ar/39Ar dating. Pilot studies would also be conducted for 36Cl dating of glacial deposits and stable isotope evaluations of alteration. The project offers a complementary record of Ross Ice Shelf behavior to that sampled by ANDRILL. It also improves the general record of McMurdo area volcanostratigraphy, which is important to interpreting landforms, glacial deposits, and ancient ice found in the Dry Valleys.<br/><br/>The broader impacts of this project include improving society's understanding of global climate change, sea level rise, and graduate and undergraduate student education. Outreach efforts include educational programs for public schools and community groups, exhibits for a local science museum, and a project website.
Abstract<br/><br/><br/>By using a tool-box of particle flux and characterization techniques appropriate to the study of particulate organic carbon fluxes out of the upper sunlit zone, WHOI researchers will attempt to evaluate the so called 'biological pump' term at the Palmer Long Term Ecological Research (PAL) site in the Western Antarctic Peninsula (WAP). The goal of these measurements is to describe the seasonal dynamics of production, export (sinking) and at-depth remineralization rates of organic matter produced in the Antarctic photic zone. This should lead to a better understanding of the biogeochemical controls on the carbon cycle in this difficult to access region. Additionally, how much of the newly fixed organic carbon is exported off the shelf, effectively driving an influx of atmospheric (including anthropogenic) CO2 to be sequestered into the deep ocean is not presently known. Comparison of prior time series sediment traps in the WAP seem to indicate smaller sinking C fluxes than other, as equally as productive Antarctic coastal regions, e.g. the Ross Sea. New observations and modeling activities will attempt to explain this discrepancy, and to account for the apparently inefficient particle export. <br/><br/><br/>"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."
This award supports a project to investigate fabrics with ground-based radar measurements near the Ross/Amundsen Sea ice-flow divide where a deep ice core will be drilled. The alignment of crystals in ice (crystal-orientation fabric) has an important effect on ice deformation. As ice deforms, anisotropic fabrics are produced, which, in turn, influence further deformation. Measurement of ice fabric variations can help reveal the deformation history of the ice and indicate how the ice will deform in the future. Ice cores provide opportunities to determine a vertical fabric profile, but horizontal variations of fabrics remain unknown. Remote sensing with ice-penetrating radar is the only way to do that over large areas. Preliminary results show that well-established polarimetric methods can detect the degree of horizontal anisotropy of fabrics and their orientation, even when they are nearly vertical-symmetric fabrics. In conjunction with ice deformation history, our first mapping of ice fabrics will contribute to modeling ice flow near the future ice core site. The project will train a graduate student and provide research experiences for two under graduate students both in field and laboratory. The project will contribute to ongoing West Antarctic ice sheet program efforts to better understand the impact of the ice sheet on global sea level rise. This project also supports an international collaboration between US and Japanese scientists.
Hall/0636687<br/><br/>This award supports a project to investigate late Pleistocene and Holocene changes in Scott Glacier, a key outlet glacier that flows directly into the Ross Sea just west of the present-day West Antarctic Ice Sheet (WAIS) grounding line. The overarching goals are to understand changes in WAIS configuration in the Ross Sea sector at and since the last glacial maximum (LGM) and to determine whether Holocene retreat observed in the Ross Embayment has ended or if it is still ongoing. To address these goals, moraine and drift sequences associated with Scott Glacier will be mapped and dated and ice thickness, surface velocity and surface mass balance will be measured to constrain an ice-flow model of the glacier. This model will be used to help interpret the dated geologic sequences. The intellectual merit of the project relates to gaining a better understanding of the West Antarctic Ice Sheet and how changing activity of fast-flowing outlet glaciers and ice streams exerts strong control on the mass balance of the ice sheet. Previous work suggests that grounding-line retreat in the Ross Sea continued into the late Holocene and left open the possibility of ongoing deglaciation as part of a long-term trend. Results from Reedy Glacier, an outlet glacier just behind the grounding line, suggest that retreat may have slowed substantially over the past 2000 years and perhaps even stopped. By coupling the work on Scott Glacier with recent data from Reedy Glacier, the grounding-line position will be bracketed and it should be possible to establish whether the retreat has truly ended or if it is ongoing. The broader impacts of the work relate to the societal relevance of an improved understanding of the West Antarctic ice sheet to establish how it will respond to current and possible future environmental changes. The work addresses this key goal of the West Antarctic Ice Sheet Initiative, as well as the International Polar Year focus on ice sheet history and dynamics. The work will develop future scientists through the education and training of one undergraduate and two Ph.D. students, interaction with K-12 students through classroom visits, web-based 'expedition' journals, letters from the field, and discussions with teachers. Results from this project will be posted with previous exposure dating results from Antarctica, on the University of Washington Cosmogenic Nuclide Lab website, which also provides information about chemical procedures and calculation methods to other scientists working with cosmogenic nuclides.
Tulaczyk/0636970<br/><br/>This award supports a project to study elevation change anomalies (henceforth ECAs), which are oval-shaped, 5-to-10 km areas observed in remote sensing images in several locations within the Ross Sea sector of the West Antarctic Ice Sheet (WAIS). Within these anomalies, surface elevation changes at rates of up to ~1 to ~2 cm per day, significantly faster than in surrounding regions. These anomalies are thought to result from filling and draining of multi-kilometer-scale subglacial water pockets. The intellectual merit of this project is that these ECA's represent an unprecedented window into the elusive world of water drainage dynamics beneath the modern Antarctic ice sheet. Although subglacial water fluxes are small compared to normal terrestrial conditions, they play an important role in controlling fast ice streaming and, potentially, stability of the ice sheet. The dearth of observational constraints on sub-ice sheet water dynamics represents one of the most important limitations on progress in quantitative modeling of ice streams and ice sheets. Such models are necessary to assess future ice sheet mass balance and to reconstruct the response of ice sheets to past climate changes. The dynamic sub-ice sheet water transport indicated by the ECAs may have also implications for studies of subglacial lakes and other subglacial environments, which may harbor life adapted to such extreme conditions. The broader impacts of this project are that it will provide advanced training opportunities to one postdoctoral fellow (UW), two female doctoral students (UCSC), who will enhance diversity in polar sciences, and at least three undergraduate students (UCSC). Project output will be relevant to broad scientific and societal interests, such as the future global sea level changes and the response of Polar Regions to climate changes. Douglas Fox, a freelance science journalist, is interested in joining the first field season to write feature articles to popular science magazines and promote the exposure of this project, and Antarctic Science in general, to mass media.
0538120<br/>Catania<br/>This award supports a project to identify and map ice surface and internal features that chronicle the sequence of events leading to the shut-down of Kamb ice stream. In particular, the project will study past grounding line migration and the relationship between that process and ice stream shutdown. The intellectual merits of the project include the fact that an understanding of such processes has important implications for our ability to accurately predict mass balance changes in this region. Currently, one of the five major West Antarctic ice streams, Kamb, is quiescent, and another, Whillans, is slowing in its downstream reaches. The Kamb shutdown appears to have begun at its downstream end but beyond that simple observation, it is not possible, yet, to draw meaningful comparisons between the two adjacent streams. We do not know if current events on Whillans Ice Stream are similar to what transpired during the Kamb shut-down. The work proposed here intends to bridge that gap. It is expected that this effort will yield useful insights into the influence of grounding line dynamics on ice stream flow. The work will involve a combination of field investigations using radio-echo sounding and GPS combined with computational efforts involving the interpretation of ice-surface features such as relict flow traces and crevasses. The broader impacts of the project will be in addressing a global environmental problem with critical societal implications, training the next generation of scientists and engineers to serve the nation, and encouraging women to pursue scientific or engineering careers. Participants from both institutions are involved in a range of public outreach activities.
This collaborative study between the Desert Research Institute, the University of California, Santa Barbara (0529087; Robin Ross), and the University of California, San Diego (0528728; Maria Vernet) will examine the relationship between sea ice extent along the Antarctic Peninsula and the life history of krill (Euphausia superba), by developing, refining, and linking diagnostic datasets and models of phytoplankton decreases in the fall, phytoplankton biomass incorporation into sea ice, sea ice growth dynamics, sea ice algal production and biomass accumulation, and larval krill energetics, condition, and survival. Krill is a key species in the food web of the Southern Ocean ecosystem, and one that is intricately involved with seasonal sea ice dynamics. Results from the Southern Ocean experiment of the Global Ocean Ecosystems Dynamics program (SO-Globec) field work as well as historical information on sea ice dynamics and krill recruitment suggest a shift in the paradigm that all pack ice is equally good krill habitat.<br/><br/>SO-Globec is a multidisciplinary effort focused on understanding the physical and biological factors that influence growth, reproduction, recruitment and survival of Antarctic krill (Euphausia superba). The program uses a multi-trophic level approach that includes the predators and competitors of Antarctic krill, represented by other zooplankton, fish, penguins, seals, and cetaceans. It is currently in a synthesis and modeling phase. This collaborative project is concerned with the lower trophic levels, and will be integrated with other synthesis and modeling studies that deal with grazers, predators, and other higher trophic levels.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>The Amundsen Sea Polynya is areally the most productive Antarctic polynya, exhibits higher chlorophyll levels during peak bloom and greater interannual variability than the better-studied Ross Sea Polynya ecosystem. Polynyas may be the key to understanding the future of polar regions as their extent is expected to increase with anthropogenic warming. The project will examine 1) sources of iron to the Amundsen Sea Polynya as a function of climate forcing, 2) phytoplankton community structure in relation to iron supply and mixed-layer depths, 3) the efficiency of the biological pump of carbon to depth and 4) the net flux of carbon as a function of climate and micronutrient forcing. The research also will compare results for the Amundsen Sea to existing data synthesis and modeling efforts for the Palmer LTER and Ross Sea. The project will 1) build close scientific collaborations between US and Swedish researchers; 2) investigate climate change implications with broad societal relevance; 3) train new researchers; 4) encourage participation in research science by underrepresented groups, and 5) involve broad dissemination of results via scientific literature and public outreach, including close interactions with NSF-supported PolarTrec and COSEE K-12 teachers.
Intellectual Merit: Pleuragramma antarcticum, the Antarctic silverfish, play a key role in the trophic pyramid of the Antarctic coastal ecosystem, acting as food for larger fishes, flying and non-flying seabirds, pinnipeds, and whales. In turn, they are predators on coastal euphausiids, including both Euphausia superba and crystallorophias. Historically, Pleuragramma have been an important food source for Adélie Penguins of the Western Antarctic Peninsula (WAP), but during the last decade Pleuragramma have disappeared from the Adélie diet. We suggest that Pleuragramma?s absence from the diets of top predators is linked to the declining sea ice canopy, which serves as a nursery for eggs and larvae during the austral spring. The research will investigate four hydrographic regimes over the WAP continental shelf with the following features: (1) persistent gyral flows that act to retain locally spawned larvae, (2) spring sea ice that has declined in recent years (3) the prevalence of adult silverfish, and (4) the presence of breeding Adélie penguins whose diets vary in the proportions of silverfish consumed. The research will evaluate the importance of local reproduction versus larval advection, and the extent to which populations in the subregions of study are genetically distinct, via analysis of population structure, otolith microchemistry and molecular genetics of fish. The Pleuragramma data will be compared with penguin diet samples taken synoptically. <br/><br/>Broader Impacts: The proposed research brings together an international group of scientists with highly complimentary suites of skills to address the fate of Pleuragramma on the WAP shelf. Graduate students will use the data acquired as part of their Ph.D research, and will receive cross-training in ornithological field techniques, molecular genetic methods and otolith isotope chemistry. The PIs will work actively with the St. Petersburg Times to produce a blog in real time with pictures and text, which will be used to interact with local schools while we are at sea and after our return. The investigators also will collaborate with the COSEE center at USF and at local schools and museums to disseminate results to the K-12 community throughout the region.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a multi-institutional, international (US - Australia) marine geologic and geophysical investigation of Prydz Bay and the MacRobertson Shelf, to be completed during an approximately 60-day cruise aboard the RVIB N.B. Palmer. The primary objective is to develop a record of climate and oceanographic change during the Quaternary, using sediment cores collected via kasten and jumbo piston coring. Core sites will be selected based on seismic profiling (Seabeam 2112 and Bathy2000). Recognition of the central role of the Antarctic Ice Sheet to global oceanic and atmospheric systems is based primarily on data collected along the West Antarctic margin, while similar extensive and high resolution data sets from the much more extensive East Antarctic margin are sparse. Goals of this project include (1) development of a century- to millennial-scale record of Holocene paleoenvironments, and (2) testing of hypotheses concerning the sedimentary record of previous glacial and interglacial events on the shelf, and evaluation of the timing and extent of maximum glaciation along this 500 km stretch of the East Antarctic margin. <br/><br/>High-resolution seismic mapping and coring of sediments deposited in inner shelf depressions will be used to reconstruct Holocene paleoenvironments. In similar depositional settings in the Antarctic Peninsula and Ross Sea, sedimentary records demonstrate millennial- and century- scale variability in primary production and sea-ice extent during the Holocene, which have been linked to chronological periodicities in radiocarbon distribution, suggesting the possible role of solar variability in driving some changes in Holocene climate. Similar high-resolution Holocene records from the East Antarctic margin will be used to develop a circum-Antarctic suite of data regarding the response of southern glacial and oceanographic systems to late Quaternary climate change. In addition, these data will help us to evaluate the response of the East Antarctic margin to global warming. <br/><br/>Initial surveys of the Prydz Channel - Amery Depression region reveal sequences deposited during previous Pleistocene interglacials. The upper Holocene and lower (undated) siliceous units can be traced over 15,000 km2 of the Prydz Channel, but more sub-bottom seismic reflection profiling in conjunction with dense coring over this region is needed to define the spatial distribution and extent of the units. Chronological work will determine the timing and duration of previous periods of glacial marine sedimentation on the East Antarctic margin during the late Pleistocene. <br/><br/>Analyses will focus on detailed sedimentologic, geochemical, micropaleontological, and paleomagnetic techniques. This multi-parameter approach is the most effective way to extract a valuable paleoenvironmental signal in these glacial marine sediments. These results are expected to lead to a significant advance in understanding of the behavior of the Antarctic ice-sheet and ocean system in the recent geologic past.<br/><br/>The combination of investigators, all with many years of experience working in high latitude marine settings, will provide an effective team to complete the project. University and College faculty (Principal Investigators on this project) will supervise a combination of undergraduate and post-graduate students involved in all stages of the project so that educational objectives will be met in tandem with the research goals of the project.
IPY: Shedding dynamic light on iron limitation: The interplay of iron<br/>limitation and dynamic irradiance in governing the phytoplankton<br/>distribution in the Ross Sea<br/><br/>The Southern Ocean plays an important role in the global carbon cycle, accounting for approximately 25% of total anthropogenic CO2 uptake by the oceans, mainly via primary production. In the Ross Sea, primary production is dominated by two taxa that are distinct in location and timing. Diatoms dominate in the shallow mixed layer of the continental shelf, whereas the colony forming Phaeocystis antarctica (Prymnesiophyceae) dominate in the more deeply mixed, open regions. Significantly, both groups have vastly different nutrient utilization characteristics, and support very different marine food webs. Their responses to climate change, and the implications for carbon export, are unclear. Previous studies show that light availability and the quality of the light climate (static versus dynamic) play a major role in defining where and when the different phytoplankton taxa bloom. However, iron (Fe) limitation of the algal communities in both the sub-Arctic and the Southern Ocean is now well documented. Moreover, phytoplankton Fe demand varies as a function of irradiance. The main hypothesis of the proposed research is: The interaction between Fe limitation and dynamic irradiance governs phytoplankton distributions in the Ross Sea. Our strategy to test this hypothesis is three-fold: 1) The photoacclimation of the different phytoplankton taxa to different light conditions under Fe limitation will be investigated in experiments in the laboratory under controlled Fe conditions. 2) The photophysiological mechanisms found in these laboratory experiments will then be tested in the field on two cruises with international IPY partners. 3) Finally, data generated during the lab and field parts of the project will be used to parameterize a dynamic light component of the Coupled Ice Atmosphere and Ocean (CIAO) model of the Ross Sea. Using the improved model, we will run future climate scenarios to test the impact of climate change on the phytoplankton community structure, distribution, primary production and carbon export in the Southern Ocean. The proposed research complies with IPY theme" Understanding Environmental change in Polar Regions" and includes participation in an international cruise. Detailed model descriptions and all of the results generated from these studies will be made public via a DynaLiFe website. Improving the CIAO model will give us and other IPY partners the opportunity to test the ecological consequences of physiological characteristics observed in Antarctic phytoplankton under current and future climate scenarios. Outreach will include participation in Stanford's Summer Program for Professional Development for Science Teachers, Stanford's School of Earth Sciences high school internship program, and development of curriculum for local science training centers, including the Chabot Space and Science Center.
Rising atmospheric carbon dioxide concentrations have resulted in greater oceanic uptake of anthropogenic carbon dioxide. Elevated partial pressure of carbon dioxide can impact marine organisms both via decreased carbonate saturation that affects calcification rates and via disturbance to acid-base (metabolic) physiology. Pteropod molluscs (Thecosomata) form shells made of aragonite, a type of calcium carbonate that is highly soluble, suggesting that these organisms may be particularly sensitive to increasing carbon dioxide and reduced carbonate ion concentration. Thecosome pteropods, which dominate the calcium carbonate export south of the Antarctic Polar Front, will be the first major group of marine calcifying organisms to experience carbonate undersaturation within parts of their present-day geographical ranges as a result of anthropogenic carbon dioxide. An unusual, co-evolved relationship between thecosomes and their specialized gymnosome predators provides a unique backdrop against which to assess the physiological and ecological importance of elevated partial pressure of carbon dioxide. Pteropods are functionally important components of the Antarctic ecosystem with potential to influence phytoplankton stocks, carbon export, and dimethyl sulfide levels that, in turn, influence global climate through ocean-atmosphere feedback loops. The research will quantify the impact of elevated carbon dioxide on a dominant aragonitic pteropod, Limacina helicina, and its specialist predator, the gymnosome Clione antarctica, in the Ross Sea through laboratory experimentation. Results will be disseminated broadly to enhance scientific understanding in this field. The project involves collaboration between researchers at a predominantly undergraduate institution with a significant enrollment of students that are typically underrepresented in the research environment (California State University San Marcos - CSUSM) and at a Ph.D.-granting institution (University of Rhode Island - URI). The program will promote education and learning through the joint education of undergraduate students and graduate students at CSUSM and URI as part of a research team, as well as through the teaching activities of the principal investigators. Dr. Keating, CSUSM professor of science education, will participate in the McMurdo fieldwork and lead the outreach opportunities for the project.
During previous NSF-sponsored research, the PI's discovered that southern elephant seal colonies once existed along the Victoria Land coast (VLC) of Antarctica, a region where they are no longer observed. Molted seal skin and hair occur along 300 km of coastline, more than 1000 km from any extant colony. The last record of a seal at a former colony site is at ~A.D. 1600. Because abandonment occurred prior to subantarctic sealing, disappearance of the VLC colony probably was due to environmental factors, possibly cooling and encroachment of land-fast, perennial sea ice that made access to haul-out sites difficult. The record of seal inhabitation along the VLC, therefore, has potential as a proxy for climate change. Elephant seals are a predominantly subantarctic species with circumpolar distribution. Genetic studies have revealed significant differentiation among populations, particularly with regard to that at Macquarie I., which is the extant population nearest to the abandoned VLC colony. Not only is the Macquarie population unique genetically, but it is has undergone unexplained decline of 2%/yr over the last 50 years3. In a pilot study, genetic analyses showed a close relationship between the VLC seals and those at Macquarie I. An understanding of the relationship between the two populations, as well as of the environmental pressures that led to the demise of the VLC colonies, will provide a better understanding of present-day population genetic structure, the effect of environmental change on seal populations, and possibly the reasons underlying the modern decline at Macquarie Island.<br/>This project addresses several key research problems: (1) Why did elephant seals colonize and then abandon the VLC? (2) What does the elephant seal record reveal about Holocene climate change and sea-ice conditions? (3) What were the foraging strategies of the seals and did these strategies change over time as climate varied? (4) How does the genetic structure of the VLC seals relate to extant populations? (5) How did genetic diversity change over time and with colony decline? (6) Using ancient samples to estimate mtDNA mutation rates, what can be learned about VLC population dynamics over time? (7) What was the ecological relationship between elephant seals and Adelie penguins that occupied the same sites, but apparently at different times? The proposed work includes the professional training of young researchers and incorporation of data into graduate and undergraduate courses.
This award supports a project to examine the stratigraphy of near-surface sediments in Taylor Valley, Antarctica. Two contrasting hypotheses have been proposed for surface sediments in lower Taylor Valley, which have important and very different implications for how the West Antarctic Ice Sheet (WAIS) responded to the sea-level rise of the last deglaciation and Holocene environmental changes. One hypothesis holds that the sediments, designated Ross I drift, directly reflect >10,000 14C-years of WAIS shrinkage in the Ross Sea during and perhaps driven by deglacial sea-level rise. The other hypothesis, holds that the Taylor sediments have little significance for WAIS change during the deglaciation. These two hypotheses reflect fundamentally different interpretations of the sediment record. Over the course of two field seasons and a third year at the home institutions, the project will test these two hypotheses using glacial geology, geochemistry, ground penetrating radar (GPR) at both 100 MHz and 400 MHz, and portable sediment coring. The intellectual merit of the proposed work is that it will test these two hypotheses and make novel use of the subsurface record that may result in new insights into WAIS sensitivity during the deglaciation. The study will also directly test the conclusion that Glacial Lake Washburn was much larger than previously proposed during the Last Glacial Maximum (LGM). This occurrence, if real, represents a stunning climate anomaly. Answers to these local ice sheet and lake questions directly pertain to larger scale issues concerning the influences of sea-level rise, climate change, and internal ice-sheet dynamics on the recession of the WAIS since the LGM. There are numerous broader impacts to this project. Understanding the glacial and lake history in the McMurdo Sound region has important implications for the role that the WAIS will play in future sea-level and global climate change. Moreover, the history of Taylor Valley has significance for the ecosystem studies currently being conducted by the LTER group. Lastly, during the course of the proposed research, the project will train two graduate and undergraduate students and the research will be featured prominently in the teaching of students.
Abstract<br/><br/><br/><br/>This project performs a paleomagnetic survey of sediment cores from Antarctica's continental margin. Its goal is to refine the magnetostratigraphy to improve regional stratigraphic correlations, help date cores that lack biostratigraphic indicators, and understand paleoenvironmental conditions and climate change. As well, these cores record the earth's magnetic field near the magnetic pole, which may offer important information to scientists modeling the geodynamo.<br/><br/>The broader impacts of this work include postdoctoral and undergraduate education. There are also implications for society's understanding of global climate change, since these techniques offer a different perspective on climate change from Antarctic marine sediment cores, which are critical to understanding the behavior of the ice sheets and their links to the global climate.
0538097<br/>Anandakrishnan<br/><br/>This award supports a project to intensively study a subglacial Antarctic lake near the geographic South Pole using seismic and radar methods. These ground-based experiments are better suited to determine the presence of water and its thickness than are airborne methods. We hypothesize that there are two end-member explanations for this feature: either the lake is thawed, but freezing on (and likely to have been freezing on through much of the current interglacial period), or it is a frozen, relict lake for which the high basal radar reflectivity is due to intergranular water in a permafrost-like layer beneath the ice. The seismic experiment we propose is ideally suited to examine these alternatives. Intermediate cases of, e.g., a thawed saturated sedimentary base or a smooth crystalline basement layer would also be resolved by this experiment. Seismic reflections are sensitive to changes in acoustic impedance which is strongly variable with fluid content, porosity, and lithology. Water has low density relative to most rocks and low seismic velocity (and nil shear wave velocity) relative to both ice and rock. Thus, discriminating between subglacial water and subglacial rock is a task ideally suited to the seismic reflection technique. This project has significant impacts outside the directly affected fields of Antarctic glaciology and geology. The lake (either thawed or sediments with thin liquid layers around the matrix particles) will have the potential for harboring novel life forms. The experiment has the potential for expanding our information about the newest frontier in life on Earth. The collaboration between PIs in the seismic community and the marine acoustics community will foster cross-disciplinary pollination of ideas, techniques, and tools. In addition to traditional seismic techniques, new methods of data analysis that have been developed by acousticians will be applied to this problem as an independent measure of lake properties. We will train students who will have a wider view of seismology than would be possible in a traditional ocean acoustics or traditional geoscience seismology program of study.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The project aims on studying sediment cores collected from Prydz Bay and the Ross Sea to unravel the Neogene paleoclimatic history of the East Antarctic ice sheet. In the light of current measurements and predictions of a substantial rise in global temperature, investigations into the sensitivity of the East Antarctic ice sheet to climate change and its role in the climate system are essential. Geological records of former periods of climate change provide an opportunity to ground truth model predictions. The scientific objective of this project is to identify a previously proposed middle Miocene transition from a more dynamic wet-based East Antarctic ice sheet to the present semi-permanent ice sheet that is partially frozen to its bed. The timing and significance of this transition is controversial due to a lack of quantitative studies on well-dated ice-proximal sedimentary sequences. This project partially fills that gap using the composition and physical properties of diamictites and sandstones to establish shifts in ice-sheet drainage pathways, paleoenvironments and basal ice conditions. The results from the two key areas around the Antarctic continental margin will provide insight into the behavior of the East Antarctic ice sheet across the middle Miocene transition and through known times of warming in the late Miocene and Pliocene.
Fungi in Antarctic ecosystems are major contributors to biodiversity and have great influence on many processes such as biodegradation and nutrient cycling. It is essential for biological surveys as well as genomic and proteomic studies to be completed so a better understanding of these organisms is obtained. Previous research has identified unique fungi associated with historic wooden structures brought to Antarctica by Robert F. Scott and Ernest Shackleton during the Heroic Era of exploration. Many of the fungi found are previously undescribed species that belong to the little known genus Cadophora. The research team will obtain important new information on the fungi present in the Ross Sea and Peninsula Regions of Antarctica, particularly their role in decomposition and nutrient recycling and their mechanisms and strategies for survival in the polar environment. New tools and methods include denaturing gradient gel electrophoresis (DGGE), real-time PCR, and proteomic profiling. These analyses will reveal key details of the physiological adaptations these fungi have evolved to carry out processes such as biodegradation and nutrient cycling under conditions that would inhibit other fungi. This work, coupled with the training and learning opportunities it provides, will be of value to many fields of study including microbial ecology, polar biology, wood microbiology, environmental science, soil science, geobiochemistry, and mycology as well as fungal phylogenetics, proteomics and genomics. Results obtained will have immediate applied use to help preserve and protect Antarctica's historic monuments. The investigations proposed are a continuation of research to identify the microbes attacking these historic structures and artifacts and to elucidate their biology and ecology in the polar environment. New research will also be done at the historic Cape Adare huts, the first wooden structures to be built in Antarctica and also at East Base, an American historic site on Stonington Island from the Admiral Byrd and Ronne Expeditions of 1939-1948. The research team will conduct vital studies needed to successfully conserve the wooden structures and artifacts at these sites and protect them for future generations
This award supports an investigation of spatial variations of ice temperature and subglacial conditions using available ice-penetrating radar data around a future deep ice coring site near the Ross and Amundsen flow divide of West Antarctic Ice Sheet. Besides geometry of reflection layers the focus will be on intensities of radar echoes from within ice deeper than several hundred meters and will also examine echoes from the bed. Preliminary studies on theory and comparison with Japanese radar data from East Antarctica suggest that large spatial variations of the vertical gradient of radar echoes from within ice exist and are caused primarily by ice temperature and secondarily by crystal-orientation fabric. The hypothesis that the vertical gradient is a proxy of ice temperature will be tested. The project will utilize an existing data set from the Support Office for Aerogeophysical Research in Antarctica (SOAR) and will complement work already underway at University of Texas to analyze the radar data. The project will provide undergraduate research experience with an emphasis on computer analysis of time series and large data sets as well as development of web-based resource of results and methods and will support an international collaboration between US and Japan through discussions on the preliminary results from their study sites. Practical procedures developed through this study will be downloadable from the project's web site in the third year and will allow investigation of other ice sheets using existing radar data sets. This project will contribute to the interpretation of the future inland West Antarctic ice core and will help in the understanding of ice sheet history and climate change.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a study to investigate the tectonic development of the southwestern Ross Sea region. Displacements between East and West Antarctica have long been proposed based on global plate circuits, apparent hot spot motions, interpretations of seafloor magnetic anomalies, paleomagnetism, and on geologic grounds. Such motions require plate boundaries crossing Antarctica, yet these boundaries have never been explicitly defined. This project will attempt to delineate the late Cenozoic - active boundary between East and West Antarctica along the Terror Rift in the western Ross Sea, where young structures have been identified, continuity between active extension and intracontinental structures can be established, and where accessibility via ship will allow new key data sets to be acquired. We will use multi-source marine and airborne geophysical data to map the fault patterns and volcanic structure along the eastern margin of the Terror Rift. The orientations of volcanic fissures and seamount alignments on the seafloor will be mapped using multibeam bathymetry. The volcanic alignments will show the regional extension or shear directions across the Terror Rift and the orientations of associated crustal stresses. Swath bathymetry and single channel seismic data will be used to document neotectonic fault patterns and the eastern limit of recent faulting. Delineation of neotectonic fault patterns will demonstrate whether the eastern margin of the Terror Rift forms a continuous boundary and whether the rift itself can be linked with postulated strike-slip faults in the northwestern Ross Sea. Seafloor findings from this project will be combined with fault kinematic and stress field determinations from the surrounding volcanic islands and the Transantarctic Mountains. The integrated results will test the propositions that the eastern boundary of the Terror Rift forms the limit of the major, late Cenozoic -active structures through the Ross Sea and that Terror Rift kinematics involve dextral transtension linked to the right-lateral strike-slip faulting to the north. These results will help constrain the kinematic and dynamic links between the West Antarctic rift system and Southern Ocean structures and any related motions between East and West Antarctica. In the first year, a collaborative structural analysis of existing multichannel and single channel seismic profiles and aeromagnetic data over the Terror Rift will be conducted. The location of volcanic vents or fissures and any fault scarps on the sea floor will be identified and a preliminary interpretation of the age and kinematics of deformation in the Terror Rift will be produced. Late in the second year, a one-month cruise on RVIB N.B. Palmer will carry out multibeam bathymetric and sidescan sonar mapping of selected portions of the seafloor of Terror Rift. Gravity, magnetics, seismic reflection and Bathy2000 3.5 kHz sub-bottom profile data will also be collected across the rift. In the third year, we will use these multisource data to map the orientations and forms of volcanic bodies and the extent and geometry of neotectonic faulting associated with the Terror Rift. The project will: 1) complete a map of neotectonic faults and volcanic structures in the Terror Rift; 2) interpret the structural pattern to derive the motions and stresses associated with development of the rift; 3) compare Terror Rift structures with faults and lineaments mapped in the Transantarctic Mountains to improve age constraints on the structures; and 4) integrate the late Cenozoic structural interpretations from the western Ross Sea with Southern Ocean plate boundary kinematics.
The Shackleton Fracture Zone (SFZ) in Drake Passage of the Southern Ocean defines a boundary between low and high phytoplankton waters. Low chlorophyll water flowing through the southern Drake Passage emerges as high chlorophyll water to the east, and recent evidence indicates that the Southern Antarctic Circumpolar Current Front (SACCF) is steered south of the SFZ onto the Antarctic Peninsula shelf where mixing between the water types occurs. The mixed water is then advected off-shelf with elevated iron and phytoplankton biomass. The SFZ is therefore an ideal natural laboratory to improve the understanding of plankton community responses to natural iron fertilization, and how these processes influence export of organic carbon to the ocean interior. The bathymetry of the region is hypothesized to influence mesoscale circulation and transport of iron, leading to the observed patterns in phytoplankton biomass. The position of the Antarctic Circumpolar Current (ACC) is further hypothesized to influence the magnitude of the flow of ACC water onto the peninsula shelf, mediating the amount of iron transported into the Scotia Sea. To address these hypotheses, a research cruise will be conducted near the SFZ and to the east in the southern Scotia Sea. A mesoscale station grid for vertical profiles, water sampling, and bottle incubation enrichment experiments will complement rapid surface surveys of chemical, plankton, and hydrographic properties. Distributions of manganese, aluminum and radium isotopes will be determined to trace iron sources and estimate mixing rates. Phytoplankton and bacterial physiological states (including responses to iron enrichment) and the structure of the plankton communities will be studied. The primary goal is to better understand how plankton productivity, community structure and export production in the Southern Ocean are affected by the coupling between bathymetry, mesoscale circulation, and distributions of limiting nutrients. The proposed work represents an interdisciplinary approach to address the fundamental physical, chemical and biological processes that contribute to the abrupt transition in chl-a which occurs near the SFZ. Given recent indications that the Southern Ocean is warming, it is important to advance the understanding of conditions that regulate the present ecosystem structure in order to predict the effects of climate variability. This project will promote training and learning across a broad spectrum of groups. Funds are included to support postdocs, graduate students, and undergraduates. In addition, this project will contribute to the development of content for the Polar Science Station website, which has been a resource since 2001 for instructors and students in adult education, home schooling, tribal schools, corrections education, family literacy programs, and the general public.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this "demonstration cruise" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the "Greenhouse-Icehouse" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program's technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the "no man's land" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program's vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this "demonstration cruise" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the "Greenhouse-Icehouse" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program's technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the "no man's land" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program's vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.
*** Caron 9714299 The analysis of microbial biodiversity of extreme environments is difficult because traditional methods for examining diversity are often ineffective for assessing species richness within these communities. Additional difficulties arise due to the difficulties of recreating and maintaining pertinent environmental features during sample collection and procession. This study focuses on the protistan assemblages (algae and protozoa) in the sea ice, sediment and ocean environments of the Ross Sea, Antarctica. The identification of protistan species in natural assemblages traditionally has entailed direct microscopical analyses as well as enrichment and culture techniques for assessing biodiversity. Determination of diversity for these assemblages in therefore susceptible to biases as a consequence of sampling, enrichment and culture, as well as selective losses due to sample preservation and concentration for microscopy. The goals of this project are: (1) to develop and apply molecular biological approaches to assess species diversity of small protists (algae and protozoa smaller than 100 micrometers) in ocean water, sea ice and sediment environments and (2) to obtain baseline physiological information on the growth rates, feeding rates and growth efficiencies of cultured protozoa under pertinent temperature regimes. Molecular biological studies will involve the use of PCR-based protocols to examine small subunit ribosomal RNA gene (srDNA) diversity. Approaches and techniques developed will be applicable to any other water body or sediment and would provide a means to examine the representativeness of protistan cultures in extant culture collections. ***
During the past few decades of oceanographic research, it has been recognized that significant variations in biogeochemical processes occur among years. Interannual variations in the Southern Ocean are known to occur in ice extent and concentration, in the composition of herbivore communities, and in bird and marine mammal distributions and reproductive success. However, little is known about the interannual variations in production of phytoplankton or the role that these variations play in the food web. This project will collect time series data on the seasonal production of phytoplankton in the southern Ross Sea, Antarctica. Furthermore, it will assess the interannual variations of the production of the two major functional groups of the system, diatoms and Phaeocystis Antarctica, a colonial haptophyte. The Ross Sea provides a unique setting for this type of investigation for a number of reasons. For example, a de facto time-series has already been initiated in the Ross Sea through the concentration of a number of programs in the past ten years. It also is well known that the species diversity is reduced relative to other systems and its seasonal production is as great as anywhere in the Antarctic. Most importantly, seasonal production of both the total phytoplankton community (as well as its two functional groups) can be estimated from late summer nutrient profiles. The project will involve short cruises on the US Coast Guard ice breakers in the southern Ross Sea that will allow the collection of water column nutrient and particulate after data at specific locations in the late summer of each of five years. Additionally, two moorings with in situ nitrate analyzers moored at fifteen will be deployed, thus collecting for the first time in the in the Antarctic a time-series of euphotic zone nutrient concentrations over the entire growing season. All nutrient data will be used to calculate seasonal production for each year in the southern Ross Sea and compared to previously collected information, thereby providing an assessment of interannual variations in net community production. Particulate matter data will allow us to estimate the amount of export from the surface layer by late summer, and therefore calculate the interannual variability of this ecosystem process. Interannual variations of seasonal production (and of the major taxa of producers) are a potentially significant feature in the growth and survival of higher trophic levels within the food web of the Ross Sea. They are also important in order to understand the natural variability in biogeochemical processes of the region. Because polar regions such as the Ross Sea are predicted to be impacted by future climate change, biological changes are also anticipated. Placing these changes in the context of natural variability is an essential element of understanding and predicting such alterations. This research thus seeks to quantify the natural variability of an Antarctic coastal system, and ultimately understand its causes and impacts on food webs and biogeochemical cycles of the Ross Sea.
The annual advance and retreat of pack ice may be the major physical determinant of spatial and temporal changes in the structure and function of antarctic marine communities. Interannual cycles and/or trends in the annual extent of pack ice may also have significant effects on all levels of the food web, from total annual primary production to breeding success in seabirds. Historical records indicate a six to eight year cycle in the maximum extent of pack ice in the winter. During this decade, winters were colder in 1980 and 1981, and again in 1986 and 1987. Winter-over survival in Adelie penguins varied on the same cycle, higher in winters with heavy pack ice. This Long Term Ecological Research (LTER) project will define ecological processes linking the extent of annual pack ice with the biological dynamics of different trophic levels within antarctic marine communities. The general focus is on interannual variability in representative populations from the antarctic marine food web and on mechanistic linkages that control the observed variability in order to develop broader generalizations applicable to other large marine environments. To achieve these objectives, data from several spatial and temporal scales, including remote sensing, a field approach that includes an annual monitoring program, a series of process-oriented research cruises, and a modeling effort to provide linkages on multiple spatial and temporal scales between biological and environmental components of the ecosystem will be employed.
PROPOSAL NO.: 0094078<br/>PRINCIPAL INVESTIGATOR: Bart, Philip<br/>INSTITUTION NAME: Louisiana State University & Agricultural and Mechanical College<br/>TITLE: CAREER: Relative frequency and phase of extreme expansions of the Antarctic Ice Sheets during the late Neogene<br/>NSF RECEIVED DATE: 07/27/2000<br/><br/>PROJECT SUMMARY<br/><br/>Expansions and contractions of the Antarctic Ice Sheets (AISs) have undoubtedly had a profound influence on Earth's climate and global sea-level. However, rather than being a single entity, the Antarctic cryosphere consists of three primary elements: 1) the East Antarctic Ice Sheet (EAIS); 2) the West Antarctic Ice Sheet (WAIS); and 3) the Antarctic Peninsula Ice Cap (APIC). The distinguishing characteristics include significant differences in: 1) ice volume; 2) substratum elevation; 3) ice-surface elevation; and 4) location with respect to latitude. Various lines of evidence indicate that the AISs have undergone significant fluctuations in the past and that fluctuations will continue to occur in the future. The exact nature of the fluctuations has been the subject of many lively debates. According to one line of reasoning, the land-based EAIS has been relatively stable, experiencing only minor fluctuations since forming in the middle Miocene, whereas the marine-based WAIS has been dynamic, waxing and waning frequently since the late Miocene. According to an alternate hypothesis, the ice sheets advanced and retreated synchronously. These two views are incompatible. <br/><br/>The first objective of this proposal is to compare the long-term past behavior of the WAIS to that of the EAIS and APIC. The fluctuations of the AISs involve many aspects (the frequency of changes, the overall magnitude of ice-volume change, etc.), and the activities proposed here specifically concern the frequency and phase of extreme advances of the ice sheet to the continental shelf. The project will build upon previous seismic-stratigraphic investigations of the continental shelves. These studies have clarified many issues concerning the minimum frequency of extreme expansions for the individual ice sheets, but some important questions remain. During the course of the project, the following questions will be evaluated.<br/><br/>Question 1) Were extreme advances of the EAIS and WAIS across the shelf of a similar frequency and coeval? This evaluation is possible because the western Ross Sea continental shelf (Northern Basin) receives drainage from the EAIS, and the eastern Ross Sea (Eastern Basin) receives drainage from the WAIS. Quantitative analyses of the extreme advances from these two areas have been conducted by Alonso et al. (1992) and Bart et al. (2000), respectively. However, the existing single-channel seismic grids are incomplete and can not be used to determine the stratigraphic correlations from Northern Basin to Eastern Basin. It is proposed that high-resolution seismic data (~2000 kms) be acquired to address this issue.<br/><br/>Question 2) Were extreme advances of the APIC across the shelf as frequent as inferred by Bart and Anderson (1995)? Bart and Anderson (1995) inferred that the APIC advanced across the continental shelf at least 30 times since the middle Miocene. This is significant because it suggests that the advances of the small APIC were an order of magnitude more frequent than the advances of the EAIS and WAIS. Others contest the Bart and Anderson (1995) glacial-unconformity interpretation of seismic reflections, and argue that the advances of the APIC were far fewer (i.e., Larter et al., 1997). The recent drilling on the Antarctic Peninsula outer continental shelf has sampled some but not all of the glacial units, but the sediment recovery was poor, and thus, the glacial history interpretation is still ambiguous. The existing high-resolution seismic grids from the Antarctic Peninsula contain only one regional strike line on the outer continental shelf. This is inadequate to address the controversy of the glacial-unconformity interpretation and the regional correlation of the recent ODP results. It is proposed that high-resolution seismic data (~1000 kms) be acquired in a forthcoming (January 2002) cruise to the Antarctic Peninsula to address these issues.<br/><br/>The second objective of this project is 1) to expand the PI's effort to integrate his ongoing and the proposed experiments into a graduate-level course at LSU, and 2) to develop a pilot outreach program with a Baton Rouge public high school. The Louisiana Department of Education has adopted scientific standards that apply to all sciences. These standards reflect what 9th through 12th grade-level students should be able to do and know. The PI will target one of these standards, the Science As Inquiry Standard 1 Benchmark. The PI will endeavor to share with the students the excitement of conducting scientific research as a way to encourage the students to pursue earth science as a field of study at the university level.
The goal of this investigation is to understand the role of snow in sea ice development processes and air-ice-ocean heat exchange interactions in the seasonal and perennial sea ice zones of the Ross Sea, the Amundsen Sea, and the Bellingshausen Sea. Observations and measurements of the characteristics of sea ice and snow will be combined with numerical models of sea-ice flooding and the entrainment of snow into the ice cover in order to gain an understanding of the sea-ice heat and mass balance, and to quantify the energy exchange within the antarctic sea-ice cover. The snow measurement program, using the RVIB Nathaniel B. Palmer, will include depth, grain size and morphology, density, temperature, thermal conductivity, water content, and stable isotope ratio. The ice measurement program will include thickness, salinity, temperature, density, brine content, and included gas volume, as well as such structural properties as the fraction of frazil, platelet, and congelation ice in the seasonal antarctic pack ice. Differences in ice types are the result of differences in the environment in which the ice forms: frazil ice is formed in supercooled sea water, normally through wind or wave-induced turbulence, while platelet and congelation ice is formed under quiescent conditions. The fraction of frazil ice is an important variable in the energy budget of the upper ocean, and contributes significantly to the stabilization of the surface layers. The numerical models will involve the thermodynamics of phase changes from liquid water to ice, along with the resulting energy transfer, brine expulsion, and the modulating effect of a snow cover. The results are expected to have broad relevance and application to understanding the effects of sea-ice processes in global change, and atmospheric, oceanographic, and remote sensing investigations of the Southern Ocean.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this "demonstration cruise" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the "Greenhouse-Icehouse" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program's technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the "no man's land" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program's vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to study the region recently occupied by the Larsen Ice Shelf in the Antarctic Peninsula. Over the last 10 years, scientists have observed a dramatic decay and disintegration of floating ice shelves along the northern end of the Antarctic Peninsula. Meteorological records and satellite observations indicate that this catastrophic decay is related to regional warming of nearly 3 degrees C in the last 50 years. While such retreat of floating ice shelves is unprecedented in historic records, current understanding of the natural variability of ice shelf systems over the last few thousand years is not understood well. This award supports a program of marine geologic research directed at filling this knowledge gap by developing an understanding of the dynamics of the northern Larsen Ice Shelf during the Holocene epoch (the last 10,000 years).<br/><br/>The Larsen Ice Shelf is located in the NW Weddell Sea along the eastern side of the Antarctic Peninsula and is currently undergoing a rapid, catastrophic retreat as documented by satellite imagery over the past five years. While the region of the northern Antarctic Peninsula has experienced a pronounced warming trend over the last 40 years, the links between this warming and global change (i.e. greenhouse warming) are not obvious. Yet the ice shelf is clearly receding at a rate unprecedented in historic time, leaving vast areas of the seafloor uncovered and in an open marine setting. This project will collect a series of short sediment cores within the Larsen Inlet and in areas that were at one time covered by the Larsen Ice Shelf. By applying established sediment and fossil criteria to the cores we hope to demonstrate whether the Larsen Ice Shelf has experienced similar periods of retreat and subsequent advance within the last 10,000 years. Past work in various regions of the Antarctic has focused on depositional models for ice shelves that allow one to discern the timing of ice shelf retreat/advance in areas of the Ross Sea, Antarctic Peninsula, and Prydz Bay. This research will lead to a much improved understanding of the dynamics of ice shelf systems and their role in past and future climate oscillations.
This project will utilize the R/VIB Nathaniel B. Palmer's transit cruises to collect marine geophysical data on targets-of-opportunity in the southern oceans. Because the Palmer generally traverses regions only sparsely surveyed with geophysical instruments, this project represents a cost-effective way to collect important new data. The work's focus is expanding our knowledge of plate motion histories for the Antarctic and surrounding plates. The ultimate goals are improving global plate reconstructions and gaining new insight into general plate kinematics and dynamics and lithospheric rheology. Only slight deviations from the straight routes are required, and we expect to operate on one cruise per year over the three years of the project. The first cruise from New Zealand to Chile will survey a flow line of Pacific-Antarctic plate motion along the Menard fracture zone, which crosses the East Pacific Rise at ~50 S latitude. Swath bathymetry, gravity, magnetics, and a small amount of seismic reflection profiling will be collected to determine the exact trace of the fracture zone and its relationship to the associated gravity anomaly seen in shipboard and satellite radar altimetry data. These observations are critical for precise plate reconstructions, and will provide GPS-navigated locations of a major fracture zone near the northern end of the Pacific-Antarctic boundary. These data will be used in combination with similar data from the Pitman fracture zone at the southwestern end of the plate boundary and magnetic anomalies from previous cruises near the Menard fracture zone to improve high-precision plate reconstructions and evaluate the limits of internal deformation of the Pacific and Antarctic plates. The science plan for cruises in following years will be designed once transit schedules are set. In terms of broader impacts, we plan to teach an on-board marine geophysics class to graduate and undergraduate students on two cruises. The class consists of daily classroom lectures about the instruments and data; several hours per day of watch standing and data processing; and work by each student on an independent research project. We expect to accommodate 15 students per class, including participants from primarily undergraduate institutions with high minority enrollments.
9317598 Asper The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. This component will focus on the collection of vertical flux samples which will be analyzed for carbon, nitrogen and total mass flux and also provided to the other investigators for their specific analyses. Profiles of the abundance of large aggregates in the water column using a non- contact photographic method will be made. These data will be used to complement other particle determinations, to investigate the role of these aggregates in particle flux and to determine the mechanisms of particle export as a function of season and phytoplankton species. The end result will be a better understanding of the bloom processes and significant contributions to the data base on aggregates and export mechanisms in this environment.
OPP98-15823 P.I. Craig Smith<br/>OPP98-16049 P.I. David DeMaster<br/><br/>Primary production in Antarctic coastal waters is highly seasonal, yielding an intense pulse of biogenic particles to the continental shelf floor. This seasonal pulse may have major ramifications for carbon cycling, benthic ecology and material burial on the west Antarctic Peninsula (WAP) shelf. Thus, we propose a multii-disciplinary program to evaluate the seafloor accumulation, fate and benthic community impacts of bloom material along a transect of three stations crossing the Antarctic shelf in the Palmer LTER study area. Using a seasonal series of five cruises to our transect, we will test the following hypostheses: (1) A substantial proportion of spring/summer export production is deposited ont eh WAP shelf as phytodetritus or fecal pellets. (2) The deposited bloom production is a source of labile particulate organic carbon for benthos for an extended period of time (months). (3) Large amounts of labile bloom POC are rapidly subducted into the sediment column by the deposit-feeding and caching activities of benthos. (4) Macrobenthic detritivores sustain a rapid increase in biomass and abundance following the spring/summer particulate organic carbon pulse. To test these hypotheses, we will evaluate seabed deposition and lability of particulate organic carbon, patterns of particulate organic carbon mixing into sediments, seasonal variations in macrofaunal and megafaunal abundance, biomass and reproductive condition, and rates of particulate organic carbon and silica mineralization and accumulation in the seabed. Fluxes of biogenic materials and radionuclides into midwater particle traps will be contrasted with seabed deposition and burial rates to establish water-column and seabed preservation efficiencies for these materials. The project will substantially improve our understanding of the spring/summer production pulse on the WAP shelf and its impacts on seafloor communities and carbon cycling in Antarctic coastal systems.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a marine geological investigation of the Amundsen Sea region toward a better understanding of the deglaciation history of the West Antarctic Ice Sheet (WAIS). The WAIS may be inherently unstable because it is the last marine-based ice sheet in the world. Unlike other embayments in West Antarctica, major ice streams draining into the Amundsen Sea from the interior of the WAIS lack buttressing ice shelves. Mass balance data for the distal portions of these ice streams (Pine Island and Thwaites glaciers) appear to be in balance or may be becoming negative. Because both ice streams have beds that slope downward toward the center of the ice sheet, grounding-line recession resulting from either continued thinning or sea-level rise could trigger irreversible grounding-line retreat, leading to ice-sheet disintegration and consequent global sea-level rise. The limited marine geological and geophysical data available from the Amundsen Sea suggest that grounded ice or an ice shelf occupied the inner Amundsen Sea embayment until perhaps as recently as 1000 to 2000 years ago, and this ice may have retreated rapidly in historic time.<br/><br/>This project, a study of the marine geology and geophysics of the Amundsen Sea continental shelf from 100 degrees W to 130 degrees W, is designed to address the Amundsen Sea part of WAIS Science Plan Priority Goal H2: "What is the deglaciation history in the eastern Ross, the Bellingshausen and Amundsen Seas?" This project will examine bathymetric data of the Amundsen Sea continental shelf to determine the positions of former ice-steam channels, and to aid in choosing sites for sediment coring. Single-channel seismic reflection studies will be conducted in order to determine sediment-thickness patterns, to aid in choice of coring sites, and to locate and identify morphologic features indicative of former grounded ice (e.g., moraines, scours, flutes, striations, till wedges and deltas, etc.). Coring will be concentrated along former ice flow-lines. Core samples will be analyzed in the laboratory for sedimentology, to determine whether of not basal tills are present (indicating former grounded ice and its former extent), and for calcareous and siliceous microfossils. The chronology of grounding-line and ice-shelf retreat from a presumed Last Glacial Maximum position near the shelf break will be established using accelerator mass spectrometry (AMS) carbon-14 dates of acid-insoluble particulate organic carbon.<br/><br/>This project will share ship time in the Amundsen Sea with a physical oceanographic project. Marine geologic data and samples collected will be integrated with findings of other investigators toward developing a comprehensive interpretation of the history of the WAIS.
This exploratory project searches for fossils on Livingston Island in the South Shetland Islands off of the Antarctic peninsula. Strata there date from 125 to 99 million years in age, a critical time in the development of various flora and fauna. With so many unknowns in the biotic history of the Antarctic, any finds of vertebrate fossils on this little explored island will be of great significance. One key question is marsupial evolution. It is assumed that marsupials of South America and Australia transited through Antarctica, but a supporting fossil record has yet to be discovered. Related investigations on Mesozoic climate will be performed through stable isotope analysis of clay and rock samples. The broader impacts of the project include graduate student education and public outreach through a museum exhibit.
9815961 <br/>BENGTSON<br/>The pack ice region surrounding Antarctica contains at least fifty percent of the world's population of seals, comprising about eighty percent of the world's total pinniped biomass. As a group, these seals are among the dominant top predators in Southern Ocean ecosystems, and the fluctuation in their abundance, growth patterns, life histories, and behavior provide a potential source of information about environmental variability integrated over a wide range of spatial and temporal scales. This proposal was developed as part of the international Antarctic Pack Ice Seals (APIS) program, which is aimed to better understand the ecological relationships between the distribution of pack ice seals and their environment. During January-February, 2000, a research cruise through the pack ice zone of the eastern Ross Sea and western Amundsen Sea will be conducted to survey and sample along six transects perpendicular to the continental shelf. Each of these transects will pass through five environmental sampling strata: continental shelf zone, Antarctic slope front, pelagic zone, the ice edge front, and the open water outside the pack ice zone. All zones but open water will be ice-covered to some degree. Surveys along each transect will gather data on bathymetry, hydrography, sea ice dynamics and characteristics, phytoplankton and ice algae stocks, prey species (e.g., fish, cephalopods and euphausiids), and seal distribution, abundance and diet. This physical and trophic approach to investigating ecological interactions among pack ice seals, prey and the physical environment will allow the interdisciplinary research team to test the hypothesis that there are measurable physical and biological features in the Southern Ocean that result in area of high biological activity by upper trophic level predators. Better insight into the interplay among pack ice seals and biological and physical features of Antarctic marine ecosystems will allow for a better prediction of fluctuation in seal population in the context of environmental change.
Antarctic notothenioid fish evolved antifreeze (AF) proteins that prevent ice crystals that enter their body fluids from growing, and thereby avoid freezing in their icy habitats. However, even in the extreme cold Antarctic marine environment, regional gradations of severity are found. The biological correlate for environmental severity in fish is the endogenous ice load, which likely determines the tolerable limit of environmental severity for notothenioid habitation. The endogenous ice load develops from environmental ice crystals entering through body surfaces and somehow localizing to the spleen. How prone the surface tissues are to ice entry, how ice reaches the spleen, and what the fate of splenic ice is, requires elucidation. Spleen sequestration of ice raises the hypothesis that macrophages may play a role in the translocation and perhaps elimination of AF-bound ice crystals. Antifreeze glycoproteins (AFGP) act in concert with a second, recently discovered antifreeze called antifreeze potentiating protein (AFPP), necessitating an assessment of the contribution of AFPP to freezing avoidance. Recent research suggests that the exocrine pancreas and the anterior stomach, not the liver, synthesize AFGPs and secrete them into the intestine, from where they may be returned to the blood. A GI-to-blood transport is a highly unconventional path for a major plasma protein and also begs the questions, What is the source of blood AFPP?. Why are two distinct AF proteins needed and what is the chronology of their evolution? What genomic changes in the DNA are associated with the development or loss of the antifreeze trait? Experiments described in this proposal address these interrelated questions of environmental, organismal, and evolutionary physiology, and will further our understanding of novel vertebrate physiologies, the limits of environmental adaptation, and climatically driven changes in the genome. The proposed research will (1) determine the temporal and spatial heterogeneity of environmental temperature and iciness in progressively more severe fish habitats in the greater McMurdo Sound area, and in the milder Arthur Harbor at Palmer Station. The splenic ice load in fishes inhabiting these sites will be determined to correlate to environmental severity and habitability. (2) Assess the surface tissue site of ice entry and their relative barrier properties in intact fish and isolated tissues preparations (3) Assess the role of immune cells in the fate of endogenous ice, (4) determine whether the blood AFGPs are from intestinal/rectal uptake, (5) examine the contribution of AFPP to the total blood AF activity (6) evaluate the progression of genomic changes in the AFGP locus across Notothenioidei as modulated by disparate thermal environments, in four selected species through the analyses of large insert DNA BAC clones. The origin and evolution of AFPP will be examined also by analyzing BAC clones encompassing the AFPP genomic locus. The broader impacts of the proposed research include training of graduate and undergraduate students in research approaches ranging from physical field measurements to cutting edge genomics. Undergraduate research projects have lead to co-authored publications and will continue to do so. Outreach includes establishing Wiki websites on topics of Antarctic fish biology and freeze avoidance, providing advisory services to the San Francisco Science Exploratorium, and making BAC libraries available to interested polar biologists. This research theme has repeatedly received national and international science news coverage and will continue to be disseminated to the public in that manner.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a collaborative research program to initiate a Global Positioning System (GPS) network to measure crustal motions in the bedrock surrounding and underlying the West Antarctic Ice Sheet (WAIS). Evaluation of the role of both tectonic and ice-induced crustal motions of the WAIS bedrock is a critical goal for understanding past, present, and future dynamics of WAIS and its potential role in future global change scenarios, as well as improving our understanding of the role of Antarctica in global plate motions. The extent of active tectonism in West Antarctica is largely speculative, as few data exist that constrain its geographic distribution, directions, or rates of deformation. Active tectonism and the influence of bedrock on the WAIS have been highlighted recently by geophysical data indicating active subglacial volcanism and control of ice streaming by the presence of sedimentary basins. The influence of bedrock crustal motion on the WAIS and its future dynamics is a fundamental issue. Existing GPS projects are located only on the fringe of the ice sheet and do not address the regional picture. It is important that baseline GPS measurements on the bedrock around and within the WAIS be started so that a basis is established for detecting change.<br/><br/>To measure crustal motions, this project will build a West Antarctica GPS Network (WAGN) of at least 15 GPS sites across the interior of West Antarctica (approximately the size of the contiguous United States from the Rocky Mountains to the Pacific coast) over a two-year period beginning in the Antarctic field season 2001-2002. The planned network is designed using the Multi-modal Occupation Strategy (MOST), in which a small number of independent GPS "roving" receivers make differential measurements against a network of continuous GPS stations for comparatively short periods at each site. This experimental strategy, successfully implemented by a number of projects in California, S America, the SW Pacific and Central Asia, minimizes logistical requirements, an essential element of application of GPS geodesy in the scattered and remote outcrops of the WAIS bedrock.<br/><br/>The WAGN program will be integrated with the GPS network that has been established linking the Antarctic Peninsula with South America through the Scotia arc (Scotia Arc GPS Project (SCARP)). It will also interface with stations currently measuring motion across the Ross Embayment, and with the continent-wide GIANT program of the Working Group on Geodesy and Geographic Information Systems of the Scientific Committee on Antarctic Research (SCAR). The GPS network will be based on permanent monuments set in solid rock outcrops that will have near-zero set-up error for roving GPS occupations, and that can be directly converted to a continuous GPS site when future technology makes autonomous operation and satellite data linkage throughout West Antarctica both reliable and economical. The planned network both depends on and complements the existing and planned continuous networks. It is presently not practical, for reasons of cost and logistics, to accomplish the measurements proposed herein with either a network of continuous stations or traditional campaigns.<br/><br/>The proposed WAGN will complement existing GPS projects by filling a major gap in coverage among several discrete crustal blocks that make up West Antarctica, a critical area of potential bedrock movements. If crustal motions are relatively slow, meaningful results will only begin to emerge within the five-year maximum period of time for an individual funded project. Hence this proposal is only to initiate the network and test precision and velocities at the most critical sites. Once built, however, the network will yield increasingly meaningful results with the passage of time. Indeed, the slower the rates turn out to be, the more important an early start to measuring. It is anticipated that the results of this project will initiate an iterative process that will gradually resolve into an understanding of the contributions from plate rotations and viscoelastic and elastic motions resulting from deglaciation and ice mass changes. Velocities obtained from initial reoccupation of the most critical sites will dictate the timing of a follow-up proposal for reoccupation of the entire network when detectable motions have occurred.
This award supports an integrated seismic, sedimentologic, and paleontologic investigation of glacio-marine stratigraphy of the Ross Sea continental shelf. The purpose of this work is to acquire seismic images and sediment cores of the glacial sediments toward a better understanding of the Cenozoic history of glaciation in the Ross Sea region. This investigation will utilize high resolution seismic profiling data to locate regions where the Pleistocene glacial till is thin or perhaps absent. Piston coring at these locations, if the till is penetrated, will provide sedimentary records of Cenozoic depositional environments and could provide important clues to fluctuations of the Antarctic Ice Sheets. The seismic profiling will provide a direct record of the grounding history of the Ross Ice Shelf during the Pleistocene and it will also allow first order correlations of Cenozoic sedimentary units that are represented by sediments recovered in the piston cores. This work will provide important proxy records of the history of both the West Antarctic Ice Sheet and the East Antarctic Ice Sheet and this, in turn, will provide important constraints to climate models.
The U.S. Global Ocean Ecosystems Dynamics (U.S. GLOBEC) program has the goal of understanding and ultimately predicting how populations of marine animal species respond to natural and anthropogenic changes in climate. Research in the Southern Ocean (SO) indicates strong coupling between climatic processes and ecosystem dynamics via the annual formation and destruction of sea ice. The Southern Ocean GLOBEC Program (SO GLOBEC) will investigate the dynamic relationship between physical processes and ecosystem responses through identification of critical parameters that affect the distribution, abundance and population dynamics of target species. The overall goals of the SO GLOBEC program are to elucidate shelf circulation processes and their effect on sea ice formation and krill distribution, and to examine the factors which govern krill survivorship and availability to higher trophic levels, including penguins, seals and whales. The focus of the U.S. contribution to the international SO GLOBEC program will be on winter processes. This component will focus on water-column primary production using direct experimental estimates, modeling restuls from a fast repetition rate fluorometer and modeling of primary production from both optical as well as biophysical models. This research will be coordinated with components focused on sea ice production and sea ice habitat. The result of the integrated SO GLOBEC program will be to improve the predictability of living marine resources, especially with respect to local and global climatic shifts.
Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea.
OPP98-15823 P.I. Craig Smith<br/>OPP98-16049 P.I. David DeMaster<br/><br/>Primary production in Antarctic coastal waters is highly seasonal, yielding an intense pulse of biogenic particles to the continental shelf floor. This seasonal pulse may have major ramifications for carbon cycling, benthic ecology and material burial on the west Antarctic Peninsula (WAP) shelf. Thus, we propose a multii-disciplinary program to evaluate the seafloor accumulation, fate and benthic community impacts of bloom material along a transect of three stations crossing the Antarctic shelf in the Palmer LTER study area. Using a seasonal series of five cruises to our transect, we will test the following hypostheses: (1) A substantial proportion of spring/summer export production is deposited ont eh WAP shelf as phytodetritus or fecal pellets. (2) The deposited bloom production is a source of labile particulate organic carbon for benthos for an extended period of time (months). (3) Large amounts of labile bloom POC are rapidly subducted into the sediment column by the deposit-feeding and caching activities of benthos. (4) Macrobenthic detritivores sustain a rapid increase in biomass and abundance following the spring/summer particulate organic carbon pulse. To test these hypotheses, we will evaluate seabed deposition and lability of particulate organic carbon, patterns of particulate organic carbon mixing into sediments, seasonal variations in macrofaunal and megafaunal abundance, biomass and reproductive condition, and rates of particulate organic carbon and silica mineralization and accumulation in the seabed. Fluxes of biogenic materials and radionuclides into midwater particle traps will be contrasted with seabed deposition and burial rates to establish water-column and seabed preservation efficiencies for these materials. The project will substantially improve our understanding of the spring/summer production pulse on the WAP shelf and its impacts on seafloor communities and carbon cycling in Antarctic coastal systems.
This project is a study of the effects of antarctic sea ice in the global climate system, through an examination of how the spatial distribution of ice and snow thickness and of open water is reflected in satellite-based synthetic aperture radar (SAR) imagery. The field investigations will be carried out from the RVIB Nathaniel B. Palmer in winter 1998 and summer 1999, and will produce observations of the snow and ice distribution, the crystal structure, stable isotopes, salinity and temperature structure of ice cores, and the stratigraphy, grain size, and water content of the snow cover. The SAR images from ERS-2 and RADARSAT will be acquired at the McMurdo ground station, and processed at the Alaska SAR Facility. These will provide information about the large-scale ice motion field and the small-scale ice deformation field, both of which contribute to the observed ice thickness distribution. In addition, a study of the spatial and temporal variation of the backscattered microwave energy will contribute to the development of numerical models that simulate the dynamic and thermodynamic interactions among the sea ice, ocean, and atmosphere. The surface data is vital for the extraction of environmental information from the radar data, and for the ultimate validation of interactive models.
Because of the extreme isolation of Antarctica since the early Oligocene one can expect to encounter a unique invertebrate fauna with a high degree of endemism. Yet, some benthic taxa include from 20 to >50 percent non-endemic species. To account for such species it has been proposed that an intermittent reciprocal exchange must occur between the antiboreal populations of South America and the Antarctic continent. One possible means by which the geographical distribution can be maintained and genetic exchange may be accomplished is by the passive dispersal of planktonic larvae. To show that such dispersal is actually accomplished it must be demonstrated that (1) larvae of sublittoral species actually are found within the Drake passage and that such larvae belong to species that occur both in the antiboreal South American and Antarctic faunas and (2) that a hydrographic mechanism exists that can explain how the passive transport of larvae may occur between the two continents. The proposed research will address these two requirements by making transects of plankton samples across the Drake passage and by examining the possibility of cross frontal exchange of larvae at the subantarctic and polar fronts of the Antarctic circumpolar current as well as the possible transport of larvae in mesoscale rings. The outcome may suggest species that in the future may profitably be examined using molecular techniques, comparing individuals from bottom populations of South America and Antarctica. The study necessarily must be of a very preliminary nature since the occurrence of planktonic larvae of sublittoral benthic species in the Drake Passage has never before been examined.
Luyendyk et.al.: OPP 0088143<br/>Bartek: OPP 0087392<br/>Diebold: OPP 0087983<br/><br/>This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a collaborative research program in marine geology and geophysics in the southern central and eastern Ross Sea. The project will conduct sites surveys for drilling from the Ross Ice Shelf into the seafloor beneath it. Many of the outstanding problems concerning the evolution of the East and West Antarctic Ice Sheets, Antarctic climate, global sea level, and the tectonic history of the West Antarctic Rift System can be addressed by drilling into the seafloor of the Ross Sea. Climate data for Cretaceous and Early Cenozoic time are lacking for this sector of Antarctica. Climate questions include: Was there any ice in Late Cretaceous time? What was the Antarctic climate during the Paleocene-Eocene global warming? When was the Cenozoic onset of Antarctic glaciation, when did glaciers reach the coast and when did they advance out onto the margin? Was the Ross Sea shelf non-marine in Late Cretaceous time; when did it become marine? Tectonic questions include: What was the timing of the Cretaceous extension in the Ross Sea rift; where was it located? What is the basement composition and structure? Where are the time and space limits of the effects of Adare Trough spreading? Another drilling objective is to sample and date the sedimentary section bounding the mapped RSU6 unconformity in the Eastern Basin and Central Trough to resolve questions about its age and regional extent. Deep Sea Drilling Project (DSDP) Leg 28 completed sampling at four drill sites in the early 1970's but had low recovery and did not sample the Early Cenozoic. Other drilling has been restricted to the McMurdo Sound area of the western Ross Sea and results can be correlated into the Victoria Land Basin but not eastward across basement highs. Further, Early Cenozoic and Cretaceous rocks have not been sampled. A new opportunity is developing to drill from the Ross Ice Shelf. This is a successor program to the Cape Roberts Drilling Project. One overriding difficulty is the need for site surveys at drilling locations under the ice shelf. This project will overcome this impediment by conducting marine geophysical drill site surveys at the front of the Ross Ice Shelf in the Central Trough and Eastern Basin. The surveys will be conducted a kilometer or two north of the ice shelf front where recent calving events have resulted in a southerly position of the ice shelf edge. In several years the northward advance of the ice shelf will override the surveyed locations and drilling could be accomplished. Systems to be used include swath bathymetry, gravity, magnetics, chirp sonar, high resolution seismic profiling, and 48 fold seismics. Cores will be collected to obtain samples for geotechnical properties, to study sub-ice shelf modern sedimentary processes, and at locations where deeper section is exposed.<br/><br/>This survey will include long profiles and detailed grids over potential drill sites. Survey lines will be tied to existing geophysical profiles and DSDP 270. A recent event that makes this plan timely is the calving of giant iceberg B-15 (in March, 2000) and others from the ice front in the eastern Ross Sea. This new calving event and one in 1987 have exposed 16,000 square kilometers of seafloor that had been covered by ice shelf for decades and is not explored. Newly exposed territory can now be mapped by modern geophysical methods. This project will map geological structure and stratigraphy below unconformity RSU6 farther south and east, study the place of Roosevelt Island in the Ross Sea rifting history, and determine subsidence history during Late Cenozoic time (post RSU6) in the far south and east. Finally the project will observe present day sedimentary processes beneath the ice shelf in the newly exposed areas.
9418153 This award supports a program aimed at providing research experiences to a broad range of undergraduate students. The program sill allow for active participation by undergraduate students in ongoing marine geologic research in Antarctica. Students will be recruited from institutions across the United States and will participate in a preparatory seminar on Antarctic science prior to the field season. This program will integrate undergraduate participation with existing marine geology and geophysics projects aboard either of the two United States Antarctic Program research vessels, the RV Polar Duke and the RVIB Nathaniel B. Palmer. Research topics will be related to the stratigraphy and/or evolution of the Antarctic continental margin, topics of increasing importance to both Antarctic and global geology. Students will have a full year following their field experience to conduct follow-up research via a senior thesis. This program is intended to provide better educational experiences to promising undergraduate students and to stimulate those students to pursue advanced degrees in geology and geophysics. ***
Anderson OPP 9527876 Abstract This award supports continuation of a long term investigation of the continental shelf sediments that is aimed at examining the configuration of the West Antarctic Ice Sheet during the last glacial maximum, the events and mechanisms involved in its retreat, and the timing of retreat. The project involves: 1) characterizing variations in the ice sheet grounding zone in a latitudinal transect extending from Ross Sea to Bransfield Basin, 2) reconstructing conditions at the ice/bed interface prior to and after ice sheet retreat, and 3) radiometrically dating ice sheet retreat along this transect. Detailed sea floor imagery (multibeam and deep-tow side-scan sonar), high resolution seismic reflection profiles, and sediment cores will be used to map and characterize prior grounding zones. Of particular concern are features that indicate the amount and organization (channelization) of basal meltwater and the extent of bed deformation that occurred in different ice streams. The timing of ice sheet retreat provides information about the link between Northern and Southern hemisphere ice expansion, and the role of eustasy in ice sheet decoupling. This research should lead to better predictive models to determine which ice streams are most unstable and likely, therefore, to serve as Oweak linksO in the long term behavior of West Antarctic Ice Sheet.
The Larsen Ice Shelf is the third largest ice shelf in Antarctica and has continued a pattern of catastrophic decay since the mid 1990's. The proposed marine geologic work at the Larsen Ice Shelf builds upon our previous NSF-OPP funding and intends to test the working hypothesis that the Larsen B Ice Shelf system has been a stable component of Antarctica's glacial system since it formed during rising sea levels 10,000 years BP. This conclusion, if supported by observations from our proposed work, is an important first step in establishing the uniqueness and consequences of rapid regional warming currently taking place across the Peninsula. Our previous work in the Larsen A and B embayments has allowed us to recognize the signature of past ice shelf fluctuations and their impact on the oceanographic and biologic environments. We have also overcome many of the limitations of standard radiocarbon dating in Antarctic marine sequences by using variations in the strength of the earth's magnetic field for correlation of sediment records and by using specific organic compounds (instead of bulk sediment) for radiocarbon dating. We intend to pursue these analytical advances and extend our sediment core stratigraphy to areas uncovered by the most recent collapse of the Larsen B Ice Shelf and areas immediately adjacent to the Larsen C Ice Shelf. In addition to the core recovery program, we intend to utilize our unique access to the ice shelf front to continue our observations of the snow/ice stratigraphy, oceanographic character, and ocean floor character. Sediment traps will also be deployed in order to measure the input of debris from glaciers that are now surging in response to the ice shelf collapse. This proposal is a multi-institutional, international (USAP, Italy, and Canada) effort that combines the established expertise in a variety of disciplines and integrates the research plan into the educational efforts of primarily undergraduate institutions but including some graduate education. This is a three-year project with field seasons planned with flexibility in order to accommodate schedules for the RVIB L.M. Gould. The Antarctic Peninsula is undergoing greater warming than almost anywhere on Earth, perhaps associated with human-induced greenhouse effects. Our proposed work contributes to understanding of these changes where they are occurring first and with greatest magnitude and impact upon the environment.
9614201 Costa Sea ice forms an extensive habitat in the Southern Ocean. Reports dating from the earliest explorations of Antarctica have described high concentrations of algae associated with sea-ice, suggesting that the ice must be an important site of production and biological activity. The magnitude and importance of ice-based production is difficult to estimate largely because the spatial and temporal distributions of ice communities have been examined in only a few regions, and the processes controlling production and community development in ice are still superficially understood. This study will examine sea ice communities in the Ross Sea region of Antarctica in conjunction with a studies of ice physics and remote sensing. The specific objectives of the study are: 1) to relate the overall distribution of ice communities in the Ross Sea to specific habitats that are formed as the result of ice formation and growth processes; 2) to study the initial formation of sea ice to document the incorporation and survival of organisms, in particular to examine winter populations within "snow-ice" layers to determine if there is a seed population established at the time of surface flooding; 3) to sample summer communities to determine the extent that highly productive "snow-ice" and "freeboard" communities develop in the deep water regions of the Ross Sea; 4) and to collect basic data on the biota, activity, and general physical and chemical characteristics of the ice assemblages, so that this study contributes to the general understanding of the ecology of the ice biota in pack ice regions.
An array of moorings will be deployed and maintained east of Cape Adare, Antarctica, at the northwestern corner of the Ross Sea to observe the properties of Antarctic Bottom Water (AABW) exiting the Ross Sea. This location has been identified from recent studies as an ideal place to make such measurements. Antarctic Bottom Water has the highest density of the major global water masses, and fills the deepest parts of the world's oceans. Because it obtains many of its characteristics during its contact with the atmosphere and with glacial ice along the continental margins of Antarctica, it is expected that changes in newly-formed AABW may represent an effective indicator for abrupt climate change. The heterogeneous nature of the source regions around Antarctica complicates the observation of newly-formed AABW properties. The two most important source regions for AABW are within the Weddell and the Ross Seas, with additional sources drawn from the east Antarctic margins. In the northwestern Weddell Sea, several programs have been undertaken in the last decade to monitor the long term variability of Weddell Sea Deep and Bottom Water, precursors of AABW originating from the Weddell Sea, however no such systematic efforts have yet been undertaken to make longterm measurements of outflow from the Ross Sea. The proposed study will significantly improve our knowledge of the long term variability in the outflow of deep and bottom water from the Ross Sea, and will provide the beginnings of a long-term monitoring effort which ultimately will allow detection of changes in the ocean in the context of global climate change. When joined with similar efforts ongoing in the Weddell Sea, long-term behavior and possible coupling of these two important sources of the ocean's deepest water mass can be examined in detail.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this "demonstration cruise" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the "Greenhouse-Icehouse" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program's technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the "no man's land" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program's vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.
The annual advance and retreat of pack ice may be the major physical determinant of spatial/temporal changes in the structure and function of antarctic marine communities. Interannual cycles and/or trends in the annual extent of pack ice may also have significant effects on all levels of the food web, from total annual primary production to breeding success in seabirds. Historical records indicate a 6 to 8 year cycle in the maximum extent of pack ice in the winter. During this decade winters were colder in 1980 and 1981, and again in 1986 and 1987. In order to understand the interactions between pack ice and ecosystem dynamics, especially the influences of the well- documented interannual variability in ice cover on representative populations, a long-term ecological research (LTER) site has been established in the Antarctic Peninsula region near Palmer Station. The LTER project, will conduct comprehensive measurements of ice-dominated ecosystems in this region with a focus on primary production, krill populations and swarms and seabirds. A primary emphasis will be placed on the development of ecosystem models that will provide a predictive capability for issues related to global environmental change. This proposal will add to the existing LTER project detailed studies of the biogeochemical cycling of carbon and associated bioelements. The microbiology and carbon flux component of LTER will provide measurements of a suite of core parameters relevant to the carbon cycle and will test several hypotheses pertaining to carbon flux, including bacterial productivity and nutrient regeneration.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to study the deep crustal structure of the Bransfield Strait region. Bransfield Strait, in the northern Antarctic Peninsula, is one of a small number of modern basins that may be critical for understanding ancient mountain-building processes. The Strait is an actively-extending marginal basin in the far southeast Pacific, between the Antarctic Peninsula and the South Shetland Islands, an inactive volcanic arc. Widespread crustal extension, accompanied by volcanism along the Strait's axis, may be associated with slow underthrusting of oceanic crust at the South Shetland Trench; similar "back-arc" extension occurred along the entire Pacific margin (now western South America/West Antarctica) of the supercontinent known as Gondwanaland during the Jurassic-Early Cretaceous. Mid-Cretaceous deformation of these basins some 100 million years ago initiated uplift of the Andes. By understanding the deep structure and evolution of Bransfield rift, it should be possible to evaluate the crustal precursor to the Andes, and thereby understand more fully the early evolution of this globally important mountain chain.<br/><br/>Years of international earth sciences research in Bransfield Strait has produced consensus on important aspects of its geologic environment: (1) It is probably a young (probably ~4 million years old) rift in preexisting Antarctic Peninsula crust; continued stretching of this crust results in complex fault patterns and associated volcanism. The volcanism, high heat flow, and mapped crustal trends are all consistent with the basin's continuing evolution as a rift; (2) The volcanism, which is recent and continuing, occurs along a "neovolcanic" zone centralized along the basin's axis. Multichannel seismic data collected aboard R/V Maurice Ewing in 1991 illustrate the following basin-wide characteristics of Bransfield Strait - a) widespread extension and faulting, b) the rise of crustal diapirs or domes associated with flower-shaped normal-fault structures, and c) a complicated system of fault-bounded segments across strike. The geophysical evidence also suggests NE-to-SW propagation of the rift, with initial crustal inflation/doming followed by deflation/subsidence, volcanism, and extension along normal faults.<br/><br/>Although Bransfield Strait exhibits geophysical and geologic evidence for extension and volcanism, continental crust fragmentation does not appear to have gone to completion in this "back-arc" basin and ocean crust is not yet being generated. Instead, Bransfield rift lies near the critical transition from intracontinental rifting to seafloor-spreading. The basin's asymmetry, and seismic evidence for shallow intracrustal detachment faulting, suggest that it may be near one end-member of the spectrum of models proposed for continental break-up. Therefore, this basin is a "natural lab" for studying diverse processes involved in forming continental margins.<br/><br/>Understanding Bransfield rift's deep crustal structure is the key to resolving its stage of evolution, and should also provide a starting point for models of Andean mountain-building. This work will define the deep structure by collecting and analyzing high-quality, high-density ocean bottom seismometer (OBS) profiles both along and across the Strait's strike. Scientific objectives are as follows: (1) to develop a detailed seismic velocity model for this rift; (2) to calibrate velocity structure and crustal thickness changes associated with presumed NE-to-SW rift propagation, as deduced from the multichannel seismic interpretations; (3) to document the degree to which deep velocity structure corresponds to along- and across-strike crustal segmentation; and (4) to assess structural relationships between the South Shetland Islands "arc" and Bransfield rift.<br/><br/>The proposed OBS data, integrated with interpretations of both Ewing profiles and those from other high-quality geophysical coverage in Bransfield Strait, will complement ongoing deep seismic analysis of Antarctic Peninsula crust to the southwest and additional OBS monitoring for deep earthquakes, in order to understand the complex plate tectonic evolution of this region.
Recent studies of marine ecosystems show conflicting evidence for trophic cascades, and in particular the relative strength of the crustacean zooplankton-phytoplankton link. The Ross Sea is a natural laboratory for investigating this apparent conflict. It is a site of seasonally high abundances of phytoplankton, characterized by regions of distinct phytoplankton taxa; the southcentral polynya is strongly dominated by the colony-forming prymnesiophyte Phaeocystis antarctica, while coastal regions of this sea are typically dominated by diatoms or flagellate species. Recent studies indicate that, while the south-central polynya exhibits a massive phytoplankton bloom, the poor food quality of P. antarctica for many crustacean zooplankton prevents direct utilization of much of this phytoplankton bloom. Rather, evidence suggests that indirect utilization of this production may be the primary mechanism by which carbon and energy become available to those higher trophic levels. Specifically, we hypothesize that nano and microzooplankton constitute an important food source for crustacean zooplankton (largely copepods and juvenile euphausiids) during the summer period in the Ross Sea where the phytoplankton assemblage is dominated by the prymnesiophyte. In turn, we also hypothesize that predation by copepods (and other Crustacea) controls and structures the species composition of these protistan assemblages. We will occupy stations in the south-central Ross Sea Polynya (RSP) and Terra Nova Bay (TNB) during austral summer to test these hypotheses. We hypothesize that the diatom species that dominate the phytoplankton assemblage in TNB constitute a direct source of nutrition to herbivorous/omnivorous zooplankton (relative to the situation in the south-central RSP). That is, the contribution of heterotrophic protists to crustacean diets will be reduced in TNB. Our research will address fundamental gaps in our knowledge of food web structure and trophic cascades, and provide better understanding of the flow of carbon and energy within the biological community of this perennially cold sea. The PIs will play active roles in public education (K-12) via curriculum development (on Antarctic biology) and teacher trainer activities in the Centers for Ocean Science Education Excellence (COSEE-West), an innovative, NSF-funded program centered at USC and UCLA.
9416989 Cande There is a significant misfit, ranging from 50 to 250 kms, of magnetic anomalies 13, 18, and 20 along the section of the Southeast Indian Ridge east of the Balleny fracture zone. This project will survey the critical plate boundaries and relevant magnetic anomalies in the South Tasman Sea, Emerald Basin and north of the Ross Sea embayment that will better constrain the history of the this plate motion. Data collected will be used to test the hypothesis that the Antarctic side of the ridge acted as a separate plate, attached to Marie Byrd Land, and that these anomalies indirectly indicate motion between East and West Antarctica between anomalies 24 and 13 time. Surveys will be conducted on the R/V W M Ewing in the Tasman Sea, and on the R/V N B Palmer north of the Ross Sea embayment. ***
Marine geological and geophysical studies of the Ross Sea and Weddell Sea continental shelves provide evidence that the ice sheet grounded near the shelf edge in these areas during the late Wisconsinan, and that the retreat of the ice sheet to its present position was rapid and probably episodic. This Award supports a project which will establish the most recent (late Wisconsin- Holocene) history of ice sheet advance and retreat in Ross Sea. The objectives include: 1) reconstruction the late Wisconsin paleodrainage regime, including ice stream divides; 2) reconstruction of former grounding zone positions; 3) constraint of the timing of ice sheet retreat from the shelf; and 4) acquisition of geophysical, sedimentological, and paleontological data which may provide indicators the environmental factors that may have influenced to ice sheet retreat. This is a joint effort between Rice University, the University of Colorado, and Hamilton College. The project involves experts in a wide variety of fields, and will interface with glaciologists, physical oceanographers and climatologists who will address the problem of ice sheet stability and the record of climatic and glaciological change.
The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. The focus of this proposal is the role of microzooplankton in controlling the production and fate of carbon during the two types of blooms. Objectives are: 1) to determine biomass, abundance, size and selected species composition of primary producer assemblages, 2) to determine similar features of nano- and microplanktonic heterotrophic assemblages, 3) to measure total community grazing on heterotrophic bacteria and phytoplankton, 4) to examine which grazers are the major herbivores and bacterivores, and 5) to measure the contribution of microzooplankton and mesozooplankton egesta, sinking of algal cells and colonies, and sinking of protozoan assemblages associated with detritus to the total carbon flux from the euphotic zone through 250 m depth. Water samples for abundance and biomass determinations will be taken and samples will be examined with epifluorescence microscopy. Grazing rates will be measured using the dilution grazing technique and the dual-isotope radiolabeling single cell method. Carbon fluxes will be determined on sinking material collected with particle interceptor traps at the base of the euphotic zone and two deeper depths, using microscopical analysis . An understanding of these processes and other fundamental processes studied by collaborating investigators will contribute to the understanding of the role of the Southern Ocean in present, past and predicted future sequestration of carbon, as well as in other global elemental cycles.
This work will perform a marine geophysical survey of sea floor spreading off Cape Adare, Antarctica. Magnetic, gravity, swath bathymetry and multi-channel seismic data will be acquired from the southern end of the Adare Basin to the northern parts of the Northern Basin and Central Trough in the Ross Embayment. Previous surveys documented 170 km of regional extension between forty-three and twenty-six million years ago, which resulted in some seafloor spreading in the Adare Basin. However, the relationship of Adare Basin spreading to the overall extension and the southward continental basins of the Ross Embayment has not been established. This relationship is critical to understanding the tectonic evolution of East and West Antarctica and linking Pacific plate motions to the rest of the world. The study will also offer unique insight into rifting processes by studying the transition of rifting between oceanic and continental lithosphere. In terms of broader impacts, this project will support two graduate students and field research experience for undergraduates. The project also involves cooperation between scientists from the US, Australia, New Zealand and Japan.
The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. <br/>This project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images.
This award supports a collaborative marine geological and geophysical project between the University of California, Santa Barbara, and the University of Alabama to study the glacial and tectonic history of the eastern Ross Sea and the Marie Byrd Land margin of West Antarctica. The goals of the project are (1) to conduct seismic imaging and piston coring to begin unraveling the history of the West Antarctic ice Sheet as recorded in the recent sediments of the continental shelf of the region, and (2) to acquire seismic images of the acoustic basement beneath the Cenozoic glacial deposits toward an understanding of the relationship between rift structure of the continental crust and Cenozoic glacial deposits of the region. This research will result in bathymetric, structural, sediment isopach, gravity and magnetic maps of the eastern Ross Sea and the Marie Byrd Land margin. This information will be integrated into an interpretation of the major glacial and structural features of the region. This project will result in a better understanding of the glacio-marine stratigraphy and glacial history of the eastern Ross Sea and Marie Byrd Land margin and, consequently, it will represent a significant contribution to the goals of the West Antarctic Ice Sheet initiative.
This award, provided jointly by the Antarctic Geology and Geophysics Program of the Office of Polar Programs and the Marine Geology and Geophysics Program of the Division of Ocean Sciences, supports research to develop improved plate rotation models for the Southwest Pacific region (between the Pacific, Antarctic, and Australian plates, and the continental fragments of New Zealand, West Antarctica, Iselin Bank, East Antarctica, and Australia). The improved rotation parameters will be used to address tectonic problems related to motion between East and West Antarctica, and in particular, the questions of relative drift between major hotspot groups and the controversy regarding a possible missing plate boundary in this region. Previous work has documented NNW-striking mid-Tertiary seafloor spreading magnetic anomalies between East and West Antarctica, representing about 150 km of opening of the Adare Trough, north of the Ross Sea. This is not enough motion to resolve the apparent discrepancy between the plate motions and motions inferred from assuming hotspot fixity. Because this motion between East and West Antarctica corresponds to a very small rotation, it points to the need for determination of finite rotations describing motions of the various plates here with a high degree of accuracy, particularly for older times. This is now possible with the datasets that will be used in this project. <br/><br/>The work will be accomplished by integrating existing data with analysis and interpretation of other data sets recently made available by Japanese and Italian scientists from their cruises in the region. It will be further augmented by acquisition of new marine geophysical data on selected transits of the R/VIB Nathaniel B. Palmer. Specific objectives of the project include the following:<br/><br/>1) improve the rotation model for mid-Tertiary extension between East and West Antarctica by including the plate boundary between the Pacific and Australia plates directly when calculating Australia-West Antarctica motion,<br/>2) improve the reconstructions for the Late Cretaceous and Early Tertiary times by including new constraints on several boundaries not previously used in the reconstructions,<br/>3) address the implications of new rotation models for the question of the fixity of global hotspots,<br/>4) re-examine the geophysical data from the Western Ross Sea embayment in light of a model for substantial mid-Cenozoic extension.
Domack: OPP 9615053 Manley: OPP 9615670 Banerjee: OPP 9615695 Dunbar: OPP 9615668 Ishman: OPP 9615669 Leventer: OPP 9714371 Abstract This award supports a multi-disciplinary, multi-institutional effort to elucidate the detailed climate history of the Antarctic Peninsula during the Holocene epoch (the last 10,000 years). The Holocene is an important, but often overlooked, portion of the Antarctic paleoclimatic record because natural variability in Holocene climate on time scales of decades to millennia can be evaluated as a model for our present "interglacial" world. This project builds on over ten years of prior investigation into the depositional processes, productivity patterns and climate regime of the Antarctic Peninsula. This previous work identified key locations that contain ultra-high resolution records of past climatic variation. These data indicate that solar cycles operating on multi-century and millennial time scales are important regulators of meltwater production and paleoproductivity. These marine records can be correlated with ice core records in Greenland and Antarctica. This project will focus on sediment dispersal patterns across the Palmer Deep region. The objective is to understand the present links between the modern climatic and oceanographic systems and sediment distribution. In particular, additional information is needed regarding the influence of sea ice on the distribution of both biogenic and terrigenous sediment distribution. Sediment samples will be collected with a variety of grab sampling and coring devices. Analytical work will include carbon-14 dating of surface sediments using accellerator mass spectrometry and standard sedimentologic, micropaleontologic and magnetic granulometric analyses. This multiparameter approach is the most effective way to extract the paleoclimatic signals contained in the marine sediment cores. Two additional objectives are the deployment of sediment traps in front of the Muller Ice Shelf in Lallemand Fjord and seismic reflection work in conjunction with site augmentation funded through the Joint Oceanographic Institute. The goal of sediment trap work is to address whether sand transport and deposition adjacent to the ice shelf calving line results from meltwater or aeolian processes. In addition, the relationship between sea ice conditions and primary productivity will be investigated. The collection of a short series of seismic lines across the Palmer Deep basins will fully resolve the question of depth to acoustic basement. The combination of investigators on this project, all with many years of experience working in high latitude settings, provides an effective team to complete the project in a timely fashion. A combination of undergraduate, graduate and post-graduate students will be involved in all stages of the project so that educational objectives will be met in-tandem with research goals of the project.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this "demonstration cruise" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the "Greenhouse-Icehouse" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program's technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the "no man's land" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program's vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.
96-14028 Dymond This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. This work is one of forty-four projects that are collaborating in the Southern Ocean Experiment, a three-year effort south of the Antarctic Polar Frontal Zone to track the flow of carbon through its organic and inorganic pathways from the air-ocean interface through the entire water column into the bottom sediment. The experiment will make use of the RVIB Nathaniel B. Palmer and the R/V Thompson. This component, a collaborative study by scientists from the Woods Hole Oceanographic Institution, Oregon State University, and the New Zealand Oceanographic Institution, concerns the export of particulate forms of carbon downward from the upper ocean. The observations will be obtained from an array of time- series sediment traps, and will be analyzed to quantify export fluxes from the Subtropical Front to the Ross Sea, over an 18- months period beginning the early austral summer of 1996. The measurement program will two annual phytoplankton blooms. The southern ocean provides a unique opportunity to investigate the processes controlling export flux in contrasting biogeochemical ocean zones demarcated by oceanic fronts. The temperature changes at the fronts coincide with gradients in nutrient concentrations and plankton ecology, resulting in a large latitudinal change in the ratio of calcium to silica taken up by the phytoplankton communities. This experiment will provide data on how the biological pump operates in the Southern Ocean and how it could potentially impact the level of atmospheric c arbon dioxide. The observed export fluxes of organic carbon, nitrogen, inorganic carbon, biogenic silica and alumina are central to the goals of the JGOFS program.
The Larsen Ice Shelf is the third largest ice shelf in Antarctica and has continued a pattern of catastrophic decay since the mid 1990's. The proposed marine geologic work at the Larsen Ice Shelf builds upon our previous NSF-OPP funding and intends to test the working hypothesis that the Larsen B Ice Shelf system has been a stable component of Antarctica's glacial system since it formed during rising sea levels 10,000 years BP. This conclusion, if supported by observations from our proposed work, is an important first step in establishing the uniqueness and consequences of rapid regional warming currently taking place across the Peninsula. Our previous work in the Larsen A and B embayments has allowed us to recognize the signature of past ice shelf fluctuations and their impact on the oceanographic and biologic environments. We have also overcome many of the limitations of standard radiocarbon dating in Antarctic marine sequences by using variations in the strength of the earth's magnetic field for correlation of sediment records and by using specific organic compounds (instead of bulk sediment) for radiocarbon dating. We intend to pursue these analytical advances and extend our sediment core stratigraphy to areas uncovered by the most recent collapse of the Larsen B Ice Shelf and areas immediately adjacent to the Larsen C Ice Shelf. In addition to the core recovery program, we intend to utilize our unique access to the ice shelf front to continue our observations of the snow/ice stratigraphy, oceanographic character, and ocean floor character. Sediment traps will also be deployed in order to measure the input of debris from glaciers that are now surging in response to the ice shelf collapse. This proposal is a multi-institutional, international (USAP, Italy, and Canada) effort that combines the established expertise in a variety of disciplines and integrates the research plan into the educational efforts of primarily undergraduate institutions but including some graduate education. This is a three-year project with field seasons planned with flexibility in order to accommodate schedules for the RVIB L.M. Gould. The Antarctic Peninsula is undergoing greater warming than almost anywhere on Earth, perhaps associated with human-induced greenhouse effects. Our proposed work contributes to understanding of these changes where they are occurring first and with greatest magnitude and impact upon the environment.
The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. This component will test the closely related hypotheses that: (1) phytoplankton growth is controlled primarily by the relationship between solar irradiance and mixed-layer depth throughout the spring (2) diatom growth rates are much higher in spring than at any other time of year, in response to the more favorable irradiance/mixing relationships, and (3) persistence of diatom blooms in summer results from the diatoms' ability to outcompete other groups under the light-limited conditions that develop in turbid, high-biomass waters. These hypotheses will be tested by (1) obtaining the first reliable estimates of the Sverdrup "critical depth" in the Antarctic so that the changing relationship between the critical depth and the mixed- layer depth in spring can be defined, and (2) estimating diatom growth rates and the gross and net production attributable to diatoms throughout the spring. The results will provide information critical to an understanding of phytoplankton bloom dynamics in the Ross Sea.
The proposed project will expand the suite of observations and lengthen the existing time series of underway surface dissolved carbon dioxide (pCO2) measurements transects across the Drake Passage on the R/VIB L.M. Gould. The additional observations include oxygen, nutrients and total CO2 (TCO2) concentrations, and the 13C to 12C ratio of TCO2. The continued and expanded time series will contribute towards two main scientific goals: the quantification of the spatial and temporal variability and the trends of surface carbon dioxide species in four major water mass regimes in the Drake Passage, and the understanding of the dominant processes and changes in those processes that contribute to the variability in surface pCO2 and the resulting air-sea flux of CO2 in the Drake Passage. The expanded program will also include the analysis of the 14C/12C of TCO2 and the specific study of the observations on one short wintertime cruise, with the objective of testing the hypothesis that the dissolved carbon dioxide in surface waters of the Drake Passage is determined by the degree of winter mixing. This is of special significance in light of two scenarios that may be affecting the ventilation of Southern Ocean deep water now and in the future: a decrease in water column stratification with the observations of higher zonal winds, or an increase in stratification due to higher precipitation and warming from climate change. If winter mixing determines the mean annual pCO2 in the Drake Passage, the increasing trend in atmospheric pCO2 should have little effect on sea surface pCO2.
The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. This component will conduct a set of process-oriented experiments designed to elucidate the controls of phytoplankton productivity, growth and accumulation as well as the mechanisms which control bacterial abundance and productivity in Antarctic waters. Specifically, the relative photosynthetic and nutrient (nitrate, ammonium) characteristics of diatom- vs. Phaeocystis- dominated assemblages will be examined to test if Phaeocystis simply grows faster under spring conditions in the Ross Sea. Phytoplankton and bacterial biomass, productivity and their interactions will be measured to elucidate the complex physical-chemical-biological interactions which occur. Substantial understanding of the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions will result from this research. Finally, because the Antarctic is the ocean's largest high-nutrient, low biomass system, and hence has the greatest potential for sequestering carbon dioxide, knowledge of the dynamics of the Ross Sea phytoplankton will also increase our understanding of the carbo n cycle of the Southern Ocean.
This project studies the relationship between opening of the Drake Passage and formation of the Antarctic ice sheet. Its goal is to answer the question: What drove the transition from a greenhouse to icehouse world thirty-four million years ago? Was it changes in circulation of the Southern Ocean caused by the separation of Antarctica from South America or was it a global effect such as decreasing atmospheric CO2 content? This study constrains the events and timing through fieldwork in South America and Antarctica and new work on marine sediment cores previously collected by the Ocean Drilling Program. It also involves an extensive, multidisciplinary analytical program. Compositional analyses of sediments and their sources will be combined with (U-Th)/He, fission-track, and Ar-Ar thermochronometry to constrain uplift and motion of the continental crust bounding the Drake Passage. Radiogenic isotope studies of fossil fish teeth found in marine sediment cores will be used to trace penetration of Pacific seawater into the Atlantic. Oxygen isotope and trace metal measurements on foraminifera will provide additional information on the timing and magnitude of ice volume changes. <br/><br/><br/><br/>The broader impacts include graduate and undergraduate education; outreach to the general public through museum exhibits and presentations, and international collaboration with scientists from Argentina, Ukraine, UK and Germany.<br/><br/><br/><br/>The project is supported under NSF's International Polar Year (IPY) research emphasis area on "Understanding Environmental Change in Polar Regions". This project is also a key component of the IPY Plates & Gates initiative (IPY Project #77), focused on determining the role of tectonic gateways in instigating polar environmental change.
This project will be the first systematic oceanographic study of the continental shelves of the Amundsen and Bellings-hausen Seas, and will include temperature and salinity profiling, water sampling for ocean chemistry, and continuous precision bathymetry. Upwelling warm deep water covers the Amundsen and Bellings-hausen shelves and delivers significant amounts of heat to the sea ice and fringing ice shelves. The regional precipitation is heavy, and has historically maintained a perennial ice cover. However, within the last few years satellite images have shown that the ice has been receding dramatically, with large areas of open water persisting through the winter in sectors that earlier had been ice-covered. These anomalous ice distributions are likely to have been accompanied by altered surface water properties, and possibly changes in the deep vertical circulation. There are indications that the conditions favoring a reduction in the sea ice may migrate westward toward the Ross Sea, and may have influenced a gradual warming over recent decades on the western side of the Antarctic Peninsula. The project will make use of the R/V Nathaniel B. Palmer in two cruises; one in the late austral summer 1993-1994, and a subse- quent cruise in September and October to observe late winter conditions.
This project is an examination of the physical and structural properties of the antarctic ice pack in the Amundsen, Bellingshausen, and Ross Seas, with the goal of defining the geographical variability of various ice types, the deformation processes that are active in the antarctic ice pack, and the large-scale thermodynamics and heat exchange processes of the ice- covered Southern Ocean. An additional goal is to relate specific characteristics of antarctic sea ice to its synthetic aperture radar (SAR) signature as observed from satellites. Physical properties include the salinity, temperature, and brine volumes, while structural properties include the fraction of frazil, platelet, and congelation ice of the seasonal antarctic pack ice. Differences in ice types are the result of differences in the environment in which the ice forms: frazil ice is formed in supercooled sea water, normally through wind or wave-induced turbulence, while platelet and congelation ice is formed under quiescent conditions. The fraction of frazil ice (which has been observed to be generally in excess of 50% in Weddell Sea ice floes) is an important variable in the energy budget of the upper ocean, and contributes significantly to the stabilization of the surface layers. The integration of sea ice field observations and synthetic aperture radar data analysis and modeling studies will contribute to a better understanding of sea ice parameters and their geophysical controls, and will be useful in defining the kind of air-ice-ocean interactions that can be studied using SAR data, as well as having broader relevance and application to atmospheric, biological, and oceanographic investigations of the Southern Ocean.
This project will study the dynamics of Circumpolar Deep Water intruding on the continental shelf of the West Antarctic coast, and the effect of this intrusion on the production of cold, dense bottom water, and melting at the base of floating glaciers and ice tongues. It will concentrate on the Amundsen Sea shelf, specifically in the region of the Pine Island Glacier, the Thwaites Glacier, and the Getz Ice Shelf. Circumpolar Deep Water (CDW) is a relatively warm water mass (warmer than +1.0 deg Celsius) which is normally confined to the outer edge of the continental shelf by an oceanic front separating this water mass from colder and saltier shelf waters. In the Amundsen Sea however, the deeper parts of the continental shelf are filled with nearly undiluted CDW, which is mixed upward, delivering significant amounts of heat to the base of the floating glacier tongues and the ice shelf. The melt rate beneath the Pine Island Glacier averages ten meters of ice per year with local annual rates reaching twenty meters. By comparison, melt rates beneath the Ross Ice Shelf are typically twenty to forty centimeters of ice per year. In addition, both the Pine Island and the Thwaites Glacier are extremely fast-moving, and have a significant effect on the regional ice mass balance of West Antarctica. This project therefore has an important connection to antarctic glaciology, particularly in assessing the combined effect of global change on the antarctic environment. The particular objectives of the project are (1) to delineate the frontal structure on the continental shelf sufficiently to define quantitatively the major routes of CDW inflow, meltwater outflow, and the westward evolution of CDW influence; (2) to use the obtained data set to validate a three-dimensional model of sub-ice ocean circulation that is currently under construction, and (3) to refine the estiamtes of in situ melting on the mass balance of the antarctic ice sheet. The observational program will be carried out from the research vessel Nathaniel B. Palmer in February and March, 1999. ***
The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. <br/>This project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). <br/><br/>This award supports a project to reconstruct the past physical and chemical climate of Antarctica, with an emphasis on the region surrounding the Ross Sea Embayment, using >60 ice cores collected in this region by US ITASE and by Australian, Brazilian, Chilean, and New Zealand ITASE teams. The ice core records are annually resolved and exceptionally well dated, and will provide, through the analyses of stable isotopes, major soluble ions and for some trace elements, instrumentally calibrated proxies for past temperature, precipitation, atmospheric circulation, chemistry of the atmosphere, sea ice extent, and volcanic activity. These records will be used to understand the role of solar, volcanic, and human forcing on Antarctic climate and to investigate the character of recent abrupt climate change over Antarctica in the context of broader Southern Hemisphere and global climate variability. The intellectual merit of the project is that ITASE has resulted in an array of ice core records, increasing the spatial resolution of observations of recent Antarctic climate variability by more than an order of magnitude and provides the basis for assessment of past and current change and establishes a framework for monitoring of future climate change in the Southern Hemisphere. This comes at a critical time as global record warming and other impacts are noted in the Southern Ocean, the Antarctic Peninsula, and on the Antarctic ice sheet. The broader impacts of the project are that Post-doctoral and graduate students involved in the project will benefit from exposure to observational and modeling approaches to climate change research and working meetings to be held at the two collaborating institutions plus other prominent climate change institutions. The results are of prime interest to the public and the media Websites hosted by the two collaborating institutions contain climate change position papers, scientific exchanges concerning current climate change issues, and scientific contribution series.
0538639<br/>Waddington<br/>This award supports a project to study the patterns of accumulation variation and microstructural properties near the WAIS Divide ice core site in a 2.5 km array of 20 m boreholes. Borehole Optical Stratigraphy (BOS) is a novel optical measurement system that detects annual-scale layers in firn that result from changes in firn microstructure, giving annual-scale records of how accumulation varied spatially over the last 40-50 years. Data from borehole optical stratigraphy can eventually be calibrated against other data on the microstructural parameters of firn to calibrate BOS's sensitivity to density, pore-volume, and pore-shape variations, and to show by proxy how these parameters vary in space across the survey area. Statistical analysis of layer-thickness and layer-brightness data will enable prediction of: 1) interannual accumulation variability, 2) variability in layer-thickness at decadal scales due to changing spatial patterns in accumulation and 3) variability in microstructure-driven metamorphism due to changing spatial patterns of microstructure. With these statistics in hand, a scientist measuring climatic shifts found in the WAIS Divide ice core will be able to determine the fraction by which signals they measure exceed the signal due to background accumulation variations. As an added benefit, while still in the field, we will determine a preliminary depth-age scale for the firn by optical layer-counting, to the depth of the deepest air-filled firn hole available. This will be a valuable result for core-drilling operations and for preliminary data-analysis on the core. In terms of broader impacts, this project will advance education by training a post-doctoral student in field techniques. The P.I. and the post-doctoral researcher will participate in an undergraduate seminar called "What is Scientific Research?", incorporating progress and results from this project. They will also communicate about their progress and field experience with a middle-school science and math class.
This award supports development of a new modeling approach that will extract information about past snow accumulation rate in both space and time in the vicinity of the future ice core near the Ross-Amundsen divide of the West Antarctic Ice Sheet (WAIS). Internal layers, detected by ice-penetrating radar, are isochrones, or former ice-sheet surfaces that have been buried by subsequent snowfall, and distorted by ice flow. Extensive ice-penetrating radar data are available over the inland portion of the WAIS. Layers have been dated back to 17,000 years before present. The radar data add the spatial dimension to the temporally resolved accumulation record from ice cores. Accumulation rates are traditionally derived from the depths of young, shallow layers, corrected for strain using a local 1-D ice-flow model. Older, deeper layers have been more affected by flow over large horizontal distances. However, it is these deeper layers that contain information on longer-term climate patterns. This project will use geophysical inverse theory and a 2.5D flow-band ice-flow forward model comprising ice-surface and layer-evolution modules, to extract robust transient accumulation patterns by assimilating multiple deeper, more-deformed layers that have previously been intractable. Histories of divide migration, geothermal flux, and surface evolution will also be produced. The grant will support the PhD research of a female graduate student who is a mentor to female socio-economically disadvantaged high-school students interested in science, through the University of Washington Women's Center. It will also provide a research<br/>experience for an undergraduate student, and contribute to a freshman seminar on Scientific Research.
Abstract<br/><br/>The project goal is to investigate the ocean-atmosphere-ice (OAI) interactions in the Amundsen and Ross Seas during the austral summer of 2007-08 using hydrographic measurements (CTD and XBT) in conjunction with (1) ship-based observations and satellite-derived estimates of sea ice concentration, and (2) ship-based observations and re-analyses of meteorological variables. The major scientific objectives are as follows: (1) to examine upper ocean characteristics along three transects in the Amundsen Sea and two transects in the Ross Sea within the context of ice-atmosphere variability over the preceding winter-spring season and as compared to other years where data are available; (2) to determine if there is additional evidence of increased upwelling of warm Circumpolar Deep Water onto the shelf in the Amundsen Sea and/or increased freshening in the Ross Sea as has been inferred by previous, but limited, ocean surveys in these regions; and (3) to examine the spatial variability in ocean thermal structure along the ship's track (outside the transects) to provide greater regional context and to compare with ocean XBT data collected during Oden 2006-07. A repeated temperature survey between the Amundsen and Ross Sea is particularly invaluable, given that this sector is the regional center of the high latitude OAI response to ENSO, thus providing opportunity for examining and linking regional oceanic temporal variability to global climate variability. The research will improve our understanding of the high latitude OAI response to climate change, and provide the physical context for the observed biology and geochemistry (investigated by our colleagues. Our results will be made widely available through research publications and internet-available databases, and through the strong public outreach efforts of Lamont-Doherty Earth Observatory. The outreach efforts will help increase awareness and understanding of anthropogenic climate change, melting ice, and ecosystem alteration in the highly sensitive Antarctic.
This project seeks to understand the evolutionary physiology of reproductive strategies in Southern Ocean marine invertebrates. The fauna of the Southern Ocean has evolved under stable, cold temperatures for approximately 14 million years. These conditions have led to the evolution of unusual physiological and biochemical characteristics, many of which may reflect adaptations to relatively low oxygen availability and high larval oxygen demands. The goal of the proposed projects is to understand latitudinal variation in the function of invertebrate egg masses in relation to oxygen availability and temperature. This relationship is critical to larval survival in the low-temperature, high-oxygen conditions found at high latitudes. In particular, the investigators will: (1) use first principles to model the diffusion of oxygen into egg and embryo masses of Antarctic organisms at environmentally relevant temperatures; (2) test model assumptions by measuring the temperature-dependence of embryonic metabolism and oxygen diffusivity through natural and artificial gels; (3) test model predictions by using oxygen microelectrodes to measure oxygen gradients in both artificial and natural egg masses, and by measuring developmental rates of embryos at different positions in masses; and (4) compare the structure and function of egg masses from the Southern Ocean to those from temperate waters. These components of the study constitute an integrated examination of the evolutionary physiology of egg mass structure and function. Studies of masses endemic to polar conditions will increase the understanding of egg mass evolution across equator-to-pole gradients in temperature and across gradients in oxygen partial pressure. The proposal will support graduate students and will involve several undergraduates in research. The PIs will also design and implement units on polar biology for undergraduate classes at their respective institutions. These educational units will focus on the PIs' photographs, video footage, experiments, and data from this project. The PIs will use web-linked video and instructional technologies to design and co-teach a new class on polar ecological physiology, will work with local grade school institutions to involve high school students in research, and will develop high school course modules about polar biology.
The research will examine blood and muscle oxygen store depletion in relation to the documented aerobic dive limit (ADL, onset of post-dive blood lactate accumulation) in diving of emperor penguins. The intellectual merits of this proposal involve its evaluation of the physiological basis of the ADL concept. The ADL is probably the most commonly-used, but rarely measured, factor to interpret and model the behavior and foraging ecology of diving animals. Based on prior studies, and on recent investigations of respiratory and blood oxygen depletion during dives of emperor penguins, it is hypothesized that the ADL is a result of the depletion of myoglobin (Mb)-bound oxygen and increased glycolysis in the primary locomotory muscles. This project will accurately define the physiological mechanisms underlying the ADL through 1) evaluation of the rate and magnitude of muscle oxygen depletion during dives in relation to the previously measured ADL, 2) characterization of the hemoglobin-oxygen dissociation curve in blood of emperor penguins and comparison of that curve to those of other diving and non-diving species, 3) application of the emperor hemoglogin-oxygen dissociation curve to previously collected oxygen and hemoglobin data in order to estimate the rate and magnitude of blood oxygen depletion during dives, and 4) measurement of muscle phosphoocreatine and glycogen concentrations in order to estimate their potential contributions to muscle energy metabolism during diving. The project also continues the census and monitoring of the emperor colonies in the Ross Sea, which is especially important in light of both fisheries activity and the movement of iceberg B15-A. Broader impacts of the project include: 1) technological development of microprocessor-based, "backpack" near-infrared spectrophotometer, which will be applicable not only to other species, but also to other fields (i.e., exercise physiology), 2) collaboration with the Department of Anesthesia at the U.S. Naval Hospital in San Diego in the training of anesthesia residents in research techniques, 3) the training and thesis research of two graduate students in these techniques and in Antarctic field research, and 4) a better understanding of the ADL concept and its use in the fields of diving behavior and physiology. In addition the annual census of emperor penguin colonies in the Ross Sea, in conjunction with the continued evaluation of previously developed remote cameras to monitor colony status, will form the basis of a new educational web site, and allow development of an educational outreach program to school children through SeaWorld of San Diego.
OPP-0230285/OPP-0230356<br/>PIs: Wilson, Terry J./Hothem, Larry D.<br/><br/>This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to conduct GPS measurements of bedrock crustal motions in an extended Transantarctic Mountains Deformation network (TAMDEF) to document neotectonic displacements due to tectonic deformation within the West Antarctic rift and/or to mass change of the Antarctic ice sheets. Horizontal displacements related to active neotectonic rifting, strike-slip translations, and volcanism will be tightly constrained by monitoring the combined TAMDEF and Italian VLNDEF networks of bedrock GPS stations along the Transantarctic Mountains and on offshore islands in the Ross Sea. Glacio-isostatic adjustments due to deglaciation since the Last Glacial Maximum and to modern mass change of the ice sheets will be modeled from GPS-derived crustal motions together with new information from other programs on the configurations, thicknesses, deglaciation history and modern mass balance of the ice sheets. Tectonic and rheological information from ongoing structural and seismic investigations in the Victoria Land region will also be integrated in the modeling. The integrative and iterative modeling will yield a holistic interpretation of neotectonics and ice sheet history that will help us to discriminate tectonic crustal displacements from viscoelastic/elastic glacio-isostatic motions. These results will provide key information to interpret broad, continental-scale crustal motion patterns detected by sparse, regionally distributed GPS continuous trackers and by spaceborne instruments. This study will contribute to international programs focused on Antarctic neotectonic and global change issues.<br/><br/>Strategies to meet these science objectives include repeat surveys of key sites in the existing TAMDEF network, extension of the array of TAMDEF sites southward about 250 km along the Transantarctic Mountains, linked measurements with the VLNDEF network, and integration of quasi-continuous trackers within the campaign network. By extending the array of bedrock sites southward, these measurements will cross gradients in predicted vertical motion due to viscoelastic rebound. The southward extension will also allow determination of the southern limit of the active Terror Rift and will provide a better baseline for constraints on any ongoing tectonic displacements across the West Antarctic rift system as a whole that might be possible using GPS data collected by the West Antarctic GPS Network. This project will also investigate unique aspects of GPS geodesy in Antarctica to determine how the error spectrum compares to mid-latitude regions and to identify the optimum measurement and data processing schemes for Antarctic conditions. The geodetic research will improve position accuracies within our network and will also yield general recommendations for deformation monitoring networks in polar regions.<br/><br/>An education and outreach program is planned and will be targeted at non-science-major undergraduate students taking Earth System Science at Ohio State University. The objective will be to illuminate the research process for nonscientists. This effort will educate students on the process of science and inform them about Antarctica and how it relates to global science issues.
The research will examine the relative importance of the physical and chemical controls on phytoplankton dynamics and carbon flux in continental margin regions of the Southern Ocean, and elucidate mechanisms by which plankton populations and carbon export might be altered by climate change. We specifically will address (1) how the phytoplankton on the continental margins of the southern Ocean respond to spatial and temporal changes in temperature, light, iron supply, and carbon dioxide levels, (2) how these factors initiate changes in phytoplankton assemblage structure, and (3) how carbon export and the efficiency of the biological pump are impacted by the biomass and composition of the phytoplankton. Two regions of study (the Amundsen and Ross Seas) will be investigated, one well studied (Ross Sea) and one poorly described (Amundsen Sea). It is hypothesized that each region will have markedly different physical forcing, giving rise to distinct chemical conditions and therefore biological responses. As such, the comparison of the two may give us insights into the mechanisms of how Antarctic continental margins will respond under changing environmental conditions. Broader impacts include participation by an international graduate student from Brazil, outreach via seminars to the general public, collaboration with the teachers-in-residence on the cruise, development of a cruise web site and interactive email exchanges with local middle school students while at sea
This project is a field and laboratory based investigation of the Vanda dike swarm in the Dry Valleys of Antarctica. These dikes crosscut Cambro-Ordovician granitoid plutons produced during the Ross Orogeny, and mark the transition between the cessation of subduction and the onset of extensional magmatism. Many dying convergent plate margins convert to extensional magmatism, and the Dry Valleys provide a magnificent opportunity to examine the shallow roots of a plate that experienced this transition. Because of their exceptional exposure, bimodal felsic and mafic compositions, and complex field relations, the Vanda dikes have the potential to reveal insights into this important phase of Antarctic tectonic history. <br/>The broader impacts include collaboration between a primarily undergraduate and two research institutions, and support for undergraduate participation in an exciting, field-based research project.
This project is an international collaborative investigation of geographic structuring, founding of new colonies, and population change of Adelie penguins (Pygoscelis adelia) nesting on Ross and Beaufort islands, Antarctica. The long-term changes occurring at these colonies are representative of changes throughout the Ross Sea, where 30% of all Adelie penguins reside, and are in some way related to changing climate. The recent grounding of two very large icebergs against Ross and Beaufort islands, with associated increased variability in sea-ice extent, has provided an unparalleled natural experiment affecting wild, interannual swings in colony productivity, foraging effort, philopatry and recruitment. Results of this natural experiment can provide insights into the demography and geographic population structuring of this species, having relevance Antarctic-wide in understanding its future responses to climate change as well as interpreting its amazingly well known Holocene history. This ongoing study will continue to consider the relative importance of resources that constrain or enhance colony growth (nesting habitat, access to food); the aspects of natural history that are affected by exploitative or interference competition among neighboring colonies (breeding success, foraging effort); climatic factors that influence the latter, especially sea ice patterns; and behavioral mechanisms that influence colony growth as a function of initial size and location (emigration, immigration). An increased effort will focus on understanding factors that affect over-winter survival. The hypothesis is that the age structure of Cape Crozier has changed over the past thirty years and no longer reflects the smaller colonies nearby. Based on recent analyses, it appears that the Ross Island penguins winter in a narrow band of sea ice north of the Antarctic Circle (where daylight persists) and south of the southern boundary of the Antarctic Circumpolar Current (where food abounds). More extensive winter ice takes the penguins north of that boundary where they incur higher mortality. Thus, where a penguin winters may be due to the timing of its post-breeding departure (which differs among colonies), which affects where it first encounters sea ice on which to molt and where it will be transported by the growing ice field. Foraging effort and interference competition for food suggested as factors driving the geographic structuring of colonies. The research includes a census of known-age penguins, studies of foraging effort and overlap among colonies; and identification of the location of molting and wintering areas. Information will be related to sea-ice conditions as quantified by satellite images. Demographic and foraging-effort models will be used to synthesize results. The iceberg natural experiment is an unparalleled opportunity to investigate the demographics of a polar seabird and its response to climate change. The marked, interannual variability in apparent philopatry, with concrete data being collected on its causes, is a condition rarely encountered among studies of vertebrates. Broader impacts include collaborating with New Zealand and Italian researchers, involving high school teachers and students in the fieldwork and continuing a website to highlight results to both scientists and the general public.
Phaeocystis Antarctica is a widely distributed phytoplankton that forms dense blooms and aggregates in the Southern Ocean. This phytoplankton and plays important roles in polar ecology and biogeochemistry, in part because it is a dominant primary producer, a main component of organic matter vertical fluxes, and the principal producer of volatile organic sulfur in the region. Yet P. Antarctica is also one of the lesser known species in terms of its physiology, life history and trophic relationships with other organisms; furthermore, information collected on other Phaeocystis species and from different locations may not be applicable to P. Antarctica in the Ross Sea. P. Antarctica occurs mainly as two morphotypes: solitary cells and mucilaginous colonies, which differ significantly in size, architecture and chemical composition. Relative dominance between solitary cells and colonies determines not only the size spectrum of the population, but also its carbon dynamics, nutrient uptake and utilization. Conventional thinking of the planktonic trophic processes is also challenged by the fact that colony formation could effectively alter the predator-prey interactions and interspecific competition. However, the factors that regulate the differences between solitary and colonial forms of P. Antarctica are not well-understood. The research objective of this proposal is therefore to address these over-arching questions:<br/>o Do P. Antarctica solitary cells and colonies differ in growth, composition and<br/>photosynthetic rates?<br/>o How do nutrients and grazers affect colony development and size distribution of P. <br/>Antarctica?<br/>o How do nutrients and grazers act synergistically to affect the long-term population<br/>dynamics of P. Antarctica? Experiments will be conducted in the McMurdo station with natural P. Antarctica assemblages and co-occurring grazers. Laboratory experiments will be conducted to study size-specific growth and photosynthetic rates of P. Antarctica, size-specific grazing mortality due to microzooplankton and mesozooplankton, the effects of macronutrients on the (nitrogen compounds) relative dominance of solitary cells and colonies, and the effects of micronutrient (Fe) and grazing related chemical signals on P. Antarctica colony development. Because this species is of critical importance in the Southern Ocean, and because this research will provide critical information on factors that regulate the role of P.Antarctica in food webs and biogeochemical cycles, a major gap in knowledge will be addressed. This project will train two marine science PhD students. The investigators will also collaborate with the School of Education and a marine science museum to communicate polar science to a broader audience.
Patterns of biodiversity, as revealed by basic research in organismal biology, may be derived from ecological and evolutionary processes expressed in unique settings, such as Antarctica. The polar regions and their faunas are commanding increased attention as declining species diversity, environmental change, commercial fisheries, and resource management are now being viewed in a global context. Commercial fishing is known to have a direct and pervasive effect on marine biodiversity, and occurs in the Southern Ocean as far south as the Ross Sea. <br/>The nature of fish biodiversity in the Antarctic is different than in all other ocean shelf areas. Waters of the Antarctic continental shelf are ice covered for most of the year and water temperatures are nearly constant at -1.5 C. In these waters components of the phyletically derived Antarctic clade of Notothenioids dominate fish diversity. In some regions, including the southwestern Ross Sea, Notothenioids are overwhelmingly dominant in terms of number of species, abundance, and biomass. Such dominance by a single taxonomic group is unique among shelf faunas of the world. In the absence of competition from a taxonomically diverse fauna, Notothenioids underwent a habitat or depth related diversification keyed to the utilization of unfilled niches in the water column, especially pelagic or partially pelagic zooplanktivory and piscivory. This has been accomplished in the absence of a swim bladder for buoyancy control. They also may form a special type of adaptive radiation known as a species flock, which is an assemblage of a disproportionately high number of related species that have evolved rapidly within a defined area where most species are endemic. Diversification in buoyancy is the hallmark of the notothenioid radiation. Buoyancy is the feature of notothenioid biology that determines whether a species lives on the substrate, in the water column or both. Buoyancy also influences other key aspects of life history including swimming, feeding and reproduction and thus has implications for the role of the species in the ecosystem. <br/>With similarities to classic evolutionary hot spots, the Antarctic shelf and its Notothenioid radiation merit further exploration. The 2004 "International Collaborative Expedition to collect and study Fish Indigenous to Sub-Antarctic Habitats," or, "ICEFISH," provided a platform for collection of notothenioid fishes from sub-Antarctic waters between South America and Africa, which will be examined in this project. This study will determine buoyancy for samples of all notothenioid species captured during the ICEFISH cruise. This essential aspect of the biology is known for only 19% of the notothenioid fauna. Also, the gross and microscopic anatomy of brains and sense organs of the phyletically basal families Bovichtidae, Eleginopidae, and of the non-Antarctic species of the primarily Antarctic family Nototheniidae will be examined. The fish biodiversity and endemicity in poorly known localities along the ICEFISH cruise track, seamounts and deep trenches will be quantified. Broader impacts include improved information for comprehending and conserving biodiversity, a scientific and societal priority.
Dissolved organic matter (DOM) is a significant chemical component in aquatic systems because it acts as an important carbon source for microorganisms, absorbs harmful radiation in sunlight, is able to complex metals, and can participate in important biogeochemical reactions. This study will investigate the biogeochemical cycling of DOM in a small coastal Antarctic pond, Pony Lake, located on Cape Royds, Ross Island. Because there are no higher plants present at this site all of the DOM in this lake is derived from microorganisms. Thus, Pony Lake is an ideal site to study the effect of physical, chemical, and microbial processes on the composition and character of the DOM pool. Finally, Pony Lake is also an ideal site to collect an International Humic Substances Society (IHSS) fulvic acid standard. Unlike other IHSS standards, this standard will not contain DOM components derived from higher land plants. To better understand the role of physical influences, the project will study the changes in the DOM pool as the lake evolves from ice-covered to ice-free conditions during the summer, as well as the relationship of DOM to the observed turnover of dominant microbial communities in the lake. Scientists will also monitor changes in microbial abundance, diversity, and productivity that may occur during the ice to open-water transition period. This research will provide much needed information regarding the relationship between microbial diversity and DOM biogeochemistry. Middle school science students will be active participants in this project through the Internet, while scientists are in the field, and in the lab.
Abstract<br/><br/>The research will continue and extend the study in the Southern Ocean that was initiated during the Oden Southern Ocean 2006 expedition in collaboration with Swedish scientist Mellissa Chierici. We will quantify carbon flux through the food web in the marginal ice zone (MIZ) by measuring size fractionated primary and secondary production, grazing and carbon flux through nanoplankton (2-20 um), microplankton (20-200um), and mesoplankton (200-2000 um). Community structure, species abundance and size specific grazing rates will be quantified using a variety of techniques both underway and at ice stations along the MIZ. The proposed cruise track extends across the Drake Passage to the Western Antarctic Peninsula (WAP) with three station transects along a gradient from the open ocean through the marginal ice zone (MIZ) in the Bellinghausen and Amundsen Seas and into the Ross Sea Polynya. Ice stations along each transect will provide material to characterize production associated with annual ice. Underway measurements of primary and secondary production (chlorophyll, CDOM, microplankton, and mesoplankton) and hydrography (temperature, salinity, pH, DO, turbidity) will establish a baseline for future cruises and as support for other projects such as biogeochemical studies on carbon dioxide drawdown and trace metal work on primary production. The outcome of these measurements will be a description of nano to mesoplankton standing stocks, community structure, and carbon flux along the MIZ in the Bellinghausen and Amundsen Seas and the Ross Sea Polynya.
Abstract<br/><br/>The research objective is (1) to determine the distributions and dynamics of a full suite of bioactive trace metals in dissolved and suspended particulate forms, along sampling transects of the Amundsen and Ross Seas. And (2) to test the sensitivity of overall cellular metal stoichiometry (metal/carbon ratios) to natural gradients in species assemblage and Fe availability. Our earlier findings from a single Ross Sea station and from a Drake Passage crossing suggest that Fe-limited phytoplankton cells are unusually enriched in Zn, Cu and Cd relative to biomass carbon, with strong implications for the biogeochemical cycling of these elements relative to carbon fluxes in the Southern Ocean. In collaboration with other researchers on the cruise, we will also measure metal stoichiometry of cells exposed to predicted 2010 temperature and carbon dioxide levels in shipboard incubation studies, as a window into possible effects of climate change on metals biogeochemistry in these regions. This proposal will support close international collaborations and lasting infrastructure development as US and Swedish scientists, and more importantly, their students, work toward shared the shared goal of understanding a region that is experiencing one of the fastest rates of climate change on the globe. Trace metal micro-nutrients are a key control on the productivity of Antarctic marine ecosystems. Our results will be made widely available through research publications and internet-available databases, and public outreach through COSEE at Rutgers University.
9911617<br/>Blankenship<br/><br/>This award, provided jointly by the Antarctic Geology and Geophysics Program, the Antarctic Glaciology Program, and the Polar Research Support Section of the Office of Polar Programs, provides funds for continuation of the Support Office for Aerogeophysical Research (SOAR). From July 1994 to July 2000, SOAR served as a facility to accomplish aerogeophysical research in Antarctica under an agreement between the University of Texas at Austin and the National Science Foundation's Office of Polar Programs (NSF/OPP). SOAR operated and maintained an aerogeophysical instrument package that consists of an ice-penetrating radar sounder, a laser altimeter, a gravimeter and a magnetometer that are tightly integrated with each other as well as with the aircraft's avionics and power packages. An array of aircraft and ground-based GPS receivers supported kinematic differential positioning using carrier-phase observations. SOAR activities included: developing aerogeophysical research projects with NSF/OPP investigators; upgrading of the aerogeophysical instrumentation package to accommodate new science projects and advances in technology; fielding this instrument package to accomplish SOAR-developed projects; and management, reduction, and analysis of the acquired aerogeophysical data. In pursuit of 9 NSF-OPP funded aerogeophysical research projects (involving 14 investigators from 9 institutions), SOAR carried out six field campaigns over a six-year period and accomplished approximately 200,000 line kilometers of aerogeophysical surveying over both East and West Antarctica in 377 flights.<br/><br/>This award supports SOAR to undertake a one year and 8 month program of aerogeophysical activities that are consistent with continuing U.S. support for geophysical research in Antarctica. <br/>- SOAR will conduct an aerogeophysical campaign during the 200/01 austral summer to accomplish surveys for two SOAR-developed projects: "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Studies" (Co-PI's Bell and Studinger, LDEO); and "Collaborative Research: Seismic Investigation of the Deep Continental Structure Across the East-West Antarctic Boundary" (Co-PI's Weins, Washington U. and Anandakrishnan, U. Alabama). After configuration and testing of the survey aircraft in McMurdo, SOAR will conduct survey flights from an NSF-supported base adjacent to the Russian Station above Lake Vostok and briefly occupy one or two remote bases on the East Antarctic ice sheet.<br/>- SOAR will reduce these aerogeophysical data and produce profiles and maps of surface elevation, bed elevation, gravity and magnetic field intensity. These results will be provided to the respective project investigators within nine months of conclusion of field activities. We will also submit a technical manuscript that describes these results to a refereed scientific journal and distribute these results to appropriate national geophysical data centers within approximately 24 months of completion of field activities.<br/>- SOAR will standardize all previously reduced SOAR data products and transfer them to the appropriate national geophysical data centers by the end of this grant.<br/>- SOAR will convene a workshop to establish a community consensus for future U.S. Antarctic aerogeophysical research. This workshop will be co-convened by Ian Dalziel and Richard Alley and will take place during the spring of 2001.<br/>- SOAR will upgrade the existing SOAR in-field quality control procedures to serve as a web-based interface for efficient browsing of many low-level SOAR data streams.<br/>- SOAR will repair and/or refurbish equipment that was used during the 2000/01 field campaign.<br/><br/>Support for SOAR is essential for accomplishing major geophysical investigations in Antarctica. Following data interpretation by the science teams, these data will provide valuable insights to the structure and evolution of the Antarctic continent.
#0125098<br/>Steve Emslie<br/><br/>Occupation History and Diet of Adelie Penguins in the Ross Sea Region<br/><br/>This project will build on previous studies to investigate the occupation history and diet of Adelie penguins (Pygoscelis adeliae) in the Ross Sea region, Antarctica, with excavations of abandoned and active penguin colonies. Numerous active and abandoned colonies exist on the Victoria Land coast, from Cape Adare to Marble Point will be sampled. Some of these sites have been radiocarbon-dated and indicate a long occupation history for Adelie penguins extending to 13,000 years before present (B. P.). The material recovered from excavations, as demonstrated from previous investigations, will include penguin bones, tissue, and eggshell fragments as well as abundant remains of prey (fish bones, otoliths, squid beaks) preserved in ornithogenic (formed from bird guano) soils. These organic remains will be quantified and subjected to radiocarbon analyses to obtain a colonization history of penguins in this region. Identification of prey remains in the sediments will allow assessment of penguin diet. Other data (ancient DNA) from these sites will be analyzed through collaboration with New Zealand scientists. Past climatic conditions will be interpreted from published ice-core and marine-sediment records. These data will be used to test the hypothesis that Adelie penguins respond to climate change, past and present, in a predictable manner. In addition, the hypothesis that Adelie penguins alter their diet in accordance with climate, sea-ice conditions, and other marine environmental variables along a latitudinal gradient will be tested. Graduate and undergraduate students will be involved in this project and a project Web site will be developed to report results and maintain educational interaction between the PI and students at local middle and high schools in Wilmington, NC.
This award supports the study of lava samples from seamounts in the Cape Adare region of the western Ross Sea. Volcanism in this area is poorly understood, and the geochemistry of these lavas may offer new insight into regional geodynamics and global mantle geochemistry. Because the Cape Adare seamounts are located on oceanic lithosphere, they may be free of the contamination that affects lavas erupted through continental areas. This one-year investigation will gather data on samples collected on a cruise to this region in 2007. It will determine seamount ages, characterize their mantle sources, assess models for their origin, and judge the potential for more detailed study. In terms of broader impacts, this project will involve graduate and undergraduate students in an exciting field expedition, followed by laboratory work using cutting-edge techniques for geochemical analyses.
This project will investigate the distribution, phylogenetic affinities and ecological aspects of ammonium-oxidizing bacteria in the Palmer Long-Term Ecological Research study area. Ammonia oxidation is the first step in the conversion of regenerated nitrogen to dinitrogen gas via denitrification, a 3-step pathway mediated by three distinct guilds of bacteria. As such, ammonia oxidation is important to the global nitrogen cycle. Ammonia oxidation and the overall process of nitrification-denitrification have received little attention in polar oceans where it is significant and where the effects of climate change on biogeochemical rates are likely to be pronounced. The goals of the studies proposed here are A) to obtain more conclusive information concerning composition of Antarctic ammonia oxidizers; B) to begin characterizing their ecophysiology and ecology; and C) to obtain cultures of the organism for more detailed studies. Water column and sea ice AOB assemblages will be characterized phylogenetically and the different kinds of AOB in various samples will be quantified. Nitrification rates will be measured across the LTER study area in water column, sea ice and sediment samples. Grazing rates on AOB will be determined and their sensitivity to UV light evaluated. In addition, the significance of urea nitrogen as a source of reduced nitrogen to AOB will be assessed and the temperature response of nitrification over temperature ranges appropriate to polar regions will be evaluated. This work will provide insights into the ecology of AOB and the knowledge needed to model how water column nitrification will respond to changes in the polar ecosystems accompanying global climate change.
Abstract<br/><br/>This Small Grants for Exploratory Research (SGER) proposal describes global change-related experimental research designed to take full advantage of a unique science opportunity on short notice, the leasing of the Oden to conduct ice-breaking operations in McMurdo Sound. <br/><br/>Our emphasis will be on using this opportunistic research platform to ask two questions about present day and future controls on Antarctic margin phytoplankton communities. These are: 1. How will expected alterations in pCO2, pH, and Fe availability in the Southern Ocean, due to future anthropogenic climate change affect phytoplankton species assemblages, carbon and nutrient biogeochemistry, and remineralization processes? 2. What is the current role of organic co-factors (vitamins) in limiting or co-limiting (along with iron ) phytoplankton growth and production in the Antarctic margin? The research approach includes experimental incubations with variation in iron enrichment, carbon dioxide concentration, and temperature. A second suite of experiments will examine co-limitation effects between vitamin B12 and Fe and B12 uptake kinetics. Changes in phytoplankton community structure, and carbon and nutrient cycling will be determined, in collaboration with many of the participating U.S. and Swedish investigators. Together, these two main objectives should allow us to obtain novel insights into the current and future controls on Antarctic margin phytoplankton growth, productivity, and carbon and nutrient biogeochemistry. In particular, the experiments in the Amundsen Sea represent a one-of-a-kind opportunity to understand algal dynamics and potential future responses to climate change in this little-studied ecosystem, and compare these results to those from the better-known Ross Sea. An important result of this study will be to build strong international collaborations with the Swedish marine science community. Additional broader impacts include participatin of an Hispanic Ph.D. student in cruise work and post-cruise analyses, and integration of results into graduate courses at the USC Catalina Lab facility. Public outreach will include presentations on global change impacts on the ocean targeted at audiences ranging from legislators and policymakers to the general public.
This award supports a three year project to develop the tools required to interpret complex patterns of flow features on the Ross Ice Shelf, which record the discharge history the ice streams flowing east off of the West Antarctic Ice Sheet. This work builds on previous research that used flow features visible in satellite image mosaics and numerical models of ice shelf flow to detect changes in grounding zone dynamics and redirection of ice stream outlets over hundreds of years. Recently observed changes on Whillans Ice Stream fit within this framework. The pattern of redirection is driven by the influence of rapid downstream thinning on the basal thermal gradient in the ice and associated "sticky spot" (ice rise) formation. In pursuing this work, the investigators recognized other records of discharge variation on the shelf that can be used to build a more complete history and understanding of ice-stream discharge variability. The intellectual merit of the proposed work lies in the fact that these records, including fracture patterns and spatial variation in ice thickness, when understood in the proper context, will yield quantitative information about the timing and dynamics of ice stream slowdowns, grounding line retreat, and the relative history of discharge between the ice streams. New tools will help further constrain this history. The laser altimeter on NASA's IceSAT has improved our knowledge of the surface elevation of Antarctic ice. IceSAT surface elevations provide a high-resolution map of ice-shelf thickness that, along with provenance maps from ice-shelf image mosaics, will be used to estimate the volumes of ice involved in past ice-stream discharge events (slowdowns, redirections, and so on). This project will develop new numerical models for fracture propagation; these will allow past variations in ice-shelf stress state to be investigated. Together, the dynamic and volume-flux histories will provide a powerful set of observations for understanding past variations in ice stream discharge and the underlying physical processes. The broader impacts of this project center on how it contributes to the ability to estimate West Antarctic contributions to global sea level rise and to answer outstanding questions about the causes of millennial and longer-scale evolution of ice streams. This work will provide a history of the most complex record of ice discharge known. In addition to the incorporation of this research into graduate student advising and normal teaching duties, the investigators are involved in other avenues of civic engagement and education. Outreach to high school students and the community at large is promoted on an annual basis by the investigators at both institutions. New outreach projects at Portland State University are developed with the assistance of researchers with expertise in student learning and achievement in science and mathematics. The collaborative research team includes two glaciologists with experience in the pairing of high resolution satellite imagery and a variety of ice-flow models and a geologist whose focus is the mechanics of rock deformation.
This award supports the study of the drift and break-up of Earth's largest icebergs, which were recently released into the Ross Sea of Antarctica as a result of calving from the Ross Ice Shelf. The scientific goals of the study are to determine the physics of iceberg motion within the dynamic context of ocean currents, winds, and sea ice, which determine the forces that drive iceberg motion, and the relationship between the iceberg and geographically and topographically determined pinning points on which the iceberg can ground. In addition, the processes by which icebergs influence the local environments (e.g., sea ice conditions near Antarctica, access to penguin rookeries, air-sea heat exchange and upwelling at iceberg margins, nutrient fluxes) will be studied. The processes by which icebergs generate globally far-reaching ocean acoustic signals that are detected within the global seismic (earthquake) sensing networks will also be studied. A featured element of the scientific research activity will be a field effort to deploy automatic weather stations, seismometer arrays and GPS-tracking stations on several of the largest icebergs presently adrift, or about to be adrift, in the Ross Sea. Data generated and relayed via satellite to home institutions in the Midwest will motivate theoretical analysis and computer simulation; and will be archived on an "iceberg" website (http://amrc.ssec.wisc.edu/amrc/iceberg.html) for access by scientists and the general public. At the most broad level, the study is justified by the fact that icebergs released by the Antarctic ice sheet represent the largest movements of fresh water within the natural environment (e.g., several of the icebergs to be studied, B15, C19 and others calved since 2000 CE, represent over 6000 cubic kilometers of fresh water-an amount roughly equivalent to 100 years of the flow of the Nile River). A better understanding of the impact of iceberg drift through the environment, and particularly the impact on ocean stratification and mixing, is essential to the understanding of the abrupt global climate changes witnessed by proxy during the ice age and of concern under conditions of future greenhouse warming. On a more specific level, the study will generate a knowledge base useful for the better management of Antarctic logistical resources (e.g., the shipping lanes to McMurdo Station) that can occasionally be influenced by adverse effects icebergs have on sea ice conditions.
Aquatic-terrestrial transition zones are crucial environments in understanding the biogeochemistry of landscapes. In temperate watersheds, these areas are generally dominated by riparian zones, which have been identified as regions of special interest for biogeochemistry because of the increased microbial activity in these locations, and because of the importance of these hydrological margins in facilitating and buffering hydrologic and biogeochemical exchanges between terrestrial and aquatic ecosystems. In the Antarctic Dry Valleys, terrestrial-aquatic transition zones are intriguing landscape features because of the vast importance of water in this polar desert, and because the material and energy budgets of dry valley ecosystems are linked by hydrology. Hydrological margins in aquatic-terrestrial transition zones will be studied in the Dry Valleys of Antarctica to answer two overarching questions: (1) what are the major controls over hydrologic and biogeochemical exchange across aquaticterrestrial transition zones and (2) to what extent do trends in nutrient cycling (e.g. nitrogen cycling) across these transition zones reflect differences in microbial communities or function vs. differences in the physical and chemical environment (e.g., redox potential)? The hydrologic gradients that define these interfaces provide the opportunity to assess the relative influence of physical conditions and microbial biodiversity and functioning upon biogeochemical cycling. Coordinated hydrologic, biogeochemical, and molecular microbial studies will be executed within hydrologic margins with the following research objectives: to determine the role of sediment characteristics, permafrost and active layer dynamics, and topography on sub-surface water content and distribution in hydrologic margins, to determine the extent to which transformations of nitrogen in hydrological margins are influenced by physical conditions (i.e., moisture, redox potential and pH) or by the presence of specific microbial communities (e.g., denitrifiers), and to characterize the microbial community structure and function of saturated zones.<br/><br/>This proposed research will provide an improved understanding of the interaction of liquid water, soils, microbial communities, and biogeochemistry within the important hydrologic margin landscape units of the dry valleys. Dry valleys streams and lakes are unique because there is no influence of higher vegetation on the movement of water and may therefore provide a model system for understanding physical and hydrological influences on microbial ecology and biogeochemistry. Hence the findings will contribute to Antarctic science as well as the broader study of riparian zones and hydrologic margins worldwide. Graduate students and undergraduate students will be involved with fieldwork and research projects. Information will be disseminated through a project web site, and outreach activities will include science education in local elementary, middle and high schools near the three universities involved.
Because of extreme isolation of the Antarctic continent since the Early Oligocene, one expects a unique invertebrate benthic fauna with a high degree of endemism. Yet some invertebrate taxa that constitute important ecological components of sedimentary benthic communities include more than 40 percent non-endemic species (e.g., benthic polychaetes). To account for non-endemic species, intermittent genetic exchange must occur between Antarctic and other (e.g. South American) populations. The most likely mechanism for such gene flow, at least for in-faunal and mobile macrobenthos, is dispersal of planktonic larvae across the sub- Antarctic and Antarctic polar fronts. To test for larval dispersal as a mechanism of maintaining genetic continuity across polar fronts, the scientists propose to (1) take plankton samples along transects across Drake passage during both the austral summer and winter seasons while concurrently collecting the appropriate hydrographic data. Such data will help elucidate the hydrographic mechanisms that allow dispersal across Drake Passage. Using a molecular phylogenetic approach, they will (2) compare seemingly identical adult forms from Antarctic and South America continents to identify genetic breaks, historical gene flow, and control for the presence of cryptic species. (3) Similar molecular tools will be used to relate planktonic larvae to their adult forms. Through this procedure, they propose to link the larval forms respectively to their Antarctic or South America origins. The proposed work builds on previous research that provides the basis for this effort to develop a synthetic understanding of historical gene flow and present day dispersal mechanism in South American/Drake Passage/Antarctic Peninsular region. Furthermore, this work represents one of the first attempts to examine recent gene flow in Antarctic benthic invertebrates. Graduate students and a postdoctoral fellow will be trained during this research.
Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea.
The Larsen Ice Shelf is the third largest ice shelf in Antarctica and has continued a pattern of catastrophic decay since the mid 1990's. The proposed marine geologic work at the Larsen Ice Shelf builds upon our previous NSF-OPP funding and intends to test the working hypothesis that the Larsen B Ice Shelf system has been a stable component of Antarctica's glacial system since it formed during rising sea levels 10,000 years BP. This conclusion, if supported by observations from our proposed work, is an important first step in establishing the uniqueness and consequences of rapid regional warming currently taking place across the Peninsula. Our previous work in the Larsen A and B embayments has allowed us to recognize the signature of past ice shelf fluctuations and their impact on the oceanographic and biologic environments. We have also overcome many of the limitations of standard radiocarbon dating in Antarctic marine sequences by using variations in the strength of the earth's magnetic field for correlation of sediment records and by using specific organic compounds (instead of bulk sediment) for radiocarbon dating. We intend to pursue these analytical advances and extend our sediment core stratigraphy to areas uncovered by the most recent collapse of the Larsen B Ice Shelf and areas immediately adjacent to the Larsen C Ice Shelf. In addition to the core recovery program, we intend to utilize our unique access to the ice shelf front to continue our observations of the snow/ice stratigraphy, oceanographic character, and ocean floor character. Sediment traps will also be deployed in order to measure the input of debris from glaciers that are now surging in response to the ice shelf collapse. This proposal is a multi-institutional, international (USAP, Italy, and Canada) effort that combines the established expertise in a variety of disciplines and integrates the research plan into the educational efforts of primarily undergraduate institutions but including some graduate education. This is a three-year project with field seasons planned with flexibility in order to accommodate schedules for the RVIB L.M. Gould. The Antarctic Peninsula is undergoing greater warming than almost anywhere on Earth, perhaps associated with human-induced greenhouse effects. Our proposed work contributes to understanding of these changes where they are occurring first and with greatest magnitude and impact upon the environment.
The Antarctic Peninsula (AP) is characterized by (1) the most rapid recent regional (winter) warming (5.35 times global mean), (2) a loss of nearly all its perennial sea ice cover on its western margin, and (3) 87% of the glaciers in retreat, contributing to global sea level rise. An ability to understand this change depends upon researchers' ability to better understand the underlying sources of this change and their driving mechanisms. Despite intensive efforts, the western AP (WAP) is chronically under-sampled. Therefore developing a capability to maintain a sustained in situ presence is a high scientific priority. The current proposal addresses this critical need through 2 objectives: (1) establish the feasibility of a Slocum Webb ocean glider to enable real-time high resolution data-adaptive polar oceanographic research; (2) address a critical question involving the regional climate change by measuring the ocean heat budget within a grid containing 14 years of ship-based ocean snapshots. This will involve the launch of the glider during the PAL-LTER austral summer research cruise, where it will fly the full along-shore distance of the LTER sample grid to be recovered at the southern extreme when the ship arrives there later in the summer. The glider will provide nearly continuous ocean property (temperature, salinity and pressure) coverage over this distance.<br/><br/>Intellectual merit. The proposed activity will involve state of the art sampling methodology that will revolutionize the ability to address climate change and other scientific issues requiring sampling densities that could not be achieved by research vessels. Specifically, the adaptive sampling capability of the glider will be used to alter its course allowing identification of routes by which the source waters of the ocean heat (and nutrients) enter the continental shelf region, while the near-continuous sampling will provide a diagnosis of how well standard shipborne stations close the heat budget. Resources are adequate for this study due to heavy leveraging by the availability of the Rutgers SLOCUM Web glider, glider control center and participation of the team of experts that flew the first such glider.<br/><br/>Broader Impacts. The proposed activity will advance discovery and understanding of the WAP responses to climate variability, to study the intricate feedback mechanisms associated with this variability and to better understand the chemical and physical processes associated with climate change. The data will be made available across the World Wide Web as it is collected, almost in real time, a potential bonanza for scientists during the upcoming International Polar Year, for classroom instruction and general outreach. Society will ultimately benefit from the improved knowledge of how climate change elsewhere in the world is impacting the unique ecosystem of the Antarctic, and driving glacial melt (sea level rise), among its other influences.
The emperor penguin, Aptenodytes forsteri, is the premier avian diver and a top predator in the Antarctic ecosystem. The routine occurrence of 500-m diver during foraging trips to sea is both a physiological and behavior enigma. The objectives of this project address how and why emperors dive as deep and long as they do. The project examines four major topics in the diving biology of emperor penguins: pressure tolerance, oxygen store management, end-organ tolerance of diving hypoxemia/ischemia, and deep-dive foraging behavior. These subjects are relevant to the role of the emperor as a top predator in the Antarctic ecosystem, and to critical concepts in diving physiology, including decompression sickness, nitrogen narcosis, shallow water blackout, hypoxemic tolerance, and extension of aerobic dive time. The following hypotheses will be tested: 1) Prevention of nitrogen narcosis and decompression sickness in emperor penguins is achieved by inhibition of pulmonary gas exchange at depth. 2) Shallow water black out does not occur because of greater cerebral hypoxemic tolerance, and, in deep dives, because of resumption of pulmonary gas exchange during final ascent. 3) The rate of depletion of the blood oxygen store is a function of depth of dive and heart rate. 4) The aerobic dive limit (ADL) reflects the onset of lactate accumulation in locomotory muscle, not total depletion of all oxygen stores. 5) Elevation of tissue antioxidant capacity and free-radical scavenging enzyme activities protect against the routine ischemia/reperfusion which occur during diving. 6) During deep dives, the Antarctic silverfish, Pleuorogramma antarcticum, is the primary prey item for emperors. <br/><br/>In addition to evaluation of the hypotheses below, the project has broader impacts in several areas such as partnership with foreign and national institutes and organizations (e.g., the National Institute of Polar Research of Japan, Centro de Investigacioines del Noroeste of Mexico, National Geographic, the University of Texas Southwestern Medical Center, and Sea World). Participation in National Geographic television documentaries will provide unique educational opportunities for the general public; development of state-of-the-art technology (e.g., blood oxygen electrode recorders, blood samplers, and miniaturized digital cameras) will lay the groundwork for future research by this group and others; and the effects of the B15 iceberg on breeding success of emperor penguins will continue to be evaluated with population censuses during planned fieldwork at several Ross Sea emperor penguin colonies.
Recent years have seen the re-establishment of large-scale marine resource utilization by humans in the Antarctic. In contrast to early sealing and whaling activity, the modern impact is directed on krill and finfish populations, most notably of the Patagonian toothfish (Dissostichus eleginoides), but also its congenor the Antarctic toothfish (Dissostichus mawsoni) in the Ross Sea. Toothfish are a valuable resource and are likely to continue to command a high price in world markets. However, extensive illegal fishing has lead to considerable concern that Patagonian toothfish populations are being over-harvested. In other parts of the world, over-harvesting of larger, commercially valuable species has led to fishing down of marine food webs, leaving impoverished, less valuable ecosystems. The goal of the Convention for the Conservation of Antarctic Marine Living Resources, part of the Antarctic Treaty System, is to allow harvest while avoiding disruptions to the Antarctic ecosystem. To achieve this, the sustainable management of the fishery depends on reliable age data. Age data allow population age structure to be modeled, so that growth, mortality and recruitment rates can be estimated and used to understand population dynamics. Age data provides the basis to determine the life history pattern of a species, to model population dynamics, and to determine which age classes are vulnerable to over-exploitation under a particular set of environmental conditions. Current age and growth information for toothfish is based on age determination methodologies which are not validated and depend on the specific laboratory and principal investigator. Recently, the Commission of the Conservation of Antarctic Marine Living Resources has endorsed three preparation methodologies using otoliths and a common set of criteria for estimating age from otolith micro-structure. The CCAMLR Otolith Network has also been initiated as a medium for exchanging samples to ensure that age estimates are comparable between readers and laboratories. However, considerable work is needed to ensure that age estimates generated by the three methodologies are accurate. One technique that has been successful is radiometric age determination, which uses the disequilibria of lead-210 and radium-226 in otoliths as a natural chronometer. This proposal brings together an international collaboration to examine population age structure for both toothfish species, in an experimental design built around radiometric validation tests of age data generated by all three preparation methodologies. To integrate the validation component within an Antarctic-wide effort to examine toothfish population age structure, sub-samples for validation work will be drawn from sample sets taken for population age studies by research teams working in Australia, New Zealand, the United Kingdom and France, as well as the United States. Scientists at Moss Landing Marine Laboratories will use radiometric age determination to independently age otoliths from Patagonian and Antarctic toothfishes. Scientists at Old Dominion University will use a system already established for aging to generate validated age data, allowing growth, mortality, and longevity to be estimated by geographic areas. The project will provide validated otolith sample sets that can be used as a foundation for a unified and validated age estimation system for the toothfishes. This study will provide information which will be disseminated to the public, policy-makers and the international community. The project will provide opportunities for under-represented students at both universities.
Satellite-tracked drifters provide simple yet powerful tools to track the motion of near-surface water on time scales ranging from the tidal/inertial band to monthly and longer. The research described herein will deploy satellite-tracked surface drifters during the annual austral summer Palmer Long Term Ecological Research (LTER) cruises in January 2006 and 2007 in order to investigate the nearsurface Lagrangian currents over the western Antarctic Peninsula (wAP) shelf. This region is experiencing the highest surface air temperature increase (roughly +0.06 degrees C per year) in Antarctica, and LTER and other investigators have found that ecosystem responses to the rapid warming and sea ice decline are already apparent at all trophic levels from phytoplankton to penguins. Building a better understanding of the regional circulation and its variability seems an essential component to understand existing physical and biological processes and longer-term changes in this important and sensitive Antarctic ecosystem. These new Lagrangian measurements will complement those made during the 2001-2003 U.S. Southern Ocean (SO) GLOBEC program and provide the first detailed look at the near-surface flow in this important section of the wAP shelf. In particular, the combined 3-year LTER Lagrangian measurements should identify (a) the source region(s) of the buoyant coastal current discovered flowing southwest along the outer coast of Adelaide Island and into Marguerite Bay during SO GLOBEC and (b) if organized cross-shelf flows occur that help create a two gyre circulation over the shelf as suggested by Hofmann et al (1996) based on regional hydrography. The principal investigators will process and analyze the LTER 2005-2007 drifter data and collaborate with Palmer LTER investigators on the interpretation and integration of the Lagrangian data with their studies. The edited data, analysis results, and animations of the drifter data with surface weather data will be posted on the LTER website for use and viewing by scientists, students, and the public. Results will be presented at national meetings and published in referred journals.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports the development of a standardized diatom image catalog or database. Diatoms are considered by many to be the most important microfossil group used today in the study of Antarctic Cenozoic marine deposits south of the Polar Front, from the near shore to deep sea. These microfossils, with walls of silica called frustules, are produced by single-celled plants (algae of the Class Bacillariophyceae) in a great variety of forms. Consequently, they have great biostratigraphic importance in the Southern Ocean and elsewhere for determining the age of marine sediments. Also, paleoclimatic and paleoceanographic studies increasingly rely on fossil diatom data. Changing biogeographic distributions of given taxa indicate shifting paleoecological conditions and provide evidence of the surface productivity and temperatures of ancient oceans. The generality of conclusions, though, is limited by variation in species concepts among workers. The broad research community relies, directly or indirectly, on the accurate identification of diatom species. Current technology can be used to greatly improve upon the standard references that have been used in making these identifications.<br/><br/>This project will develop an interactive digital-image catalog of modern and Cenozoic fossil diatoms of the Southern Ocean called "DiatomWare" for use by specialists and educators as an aid in rapid, accurate, and consistent species identification. As such, this will be a researcher's resource. It will be especially useful where it is not possible to maintain standard library resources such as onboard research vessels or at remote stations such as McMurdo Station. Major Antarctic geological drilling initiatives such as the new SHALDRIL project and the pending ANDRILL project will benefit from this product because they will rely heavily on diatom biostratigraphy to achieve their research objectives. The DiatomWare image database will be modeled on NannoWare, which was released in October 2002 on CD-ROM as a publication of the International Nannoplankton Association. BugCam will be adapted and modified as necessary to run the DiatomWare database, which can then be run from desktop or laptop computers. Images and text for the database will be scanned from the literature or captured in digital form from light or scanning electron microscopes.<br/><br/>The software interface will include a number of data fields that can be accessed by the click of a mouse button. Primary information will be the images and descriptions of the holotypes. In addition, representative images of paratypes or hypotypes will be included whenever possible in plain transmitted, differential interference contrast light and, when available, as drawings and SEM images. Also included will be a 35-word or less English diagnosis ("mini-description"), the biostratigraphic range in terms of zones and linear time, bibliographic references, lists of species considered junior synonyms, and similar species. The list of similar species will be cross-referenced with their respective image files to enable quick access for direct visual comparison on the viewing screen. Multiple images can be brought to the viewing screen simultaneously, and a zoom feature will permit image examination at a wide range of magnifications. Buttons will allow range charts, a bibliography, and key public-domain publications from the literature to be called up from within the program. The DiatomWare/BugCam package will be distributed at a nominal cost through a major nonprofit society via CD-ROM and free to Internet users on the Worldwide Web. Quality control measures will include critical review of the finalized database by a network of qualified specialists. The completed database will include descriptions and images of between 350 and 400 species, including fossil as well as modern forms that have no fossil record.<br/><br/>The development of the proposed diatom image database will be important to all research fields that depend on accurate biostratigraphic dating and paleoenvironmental interpretation of Antarctic marine sediments and plankton. The database will also serve as a valuable teaching tool for micropaleontology students and their professors, will provide a rapid means of keying down species for micropaleontologists of varying experience and background, and will promote a uniformity of taxonomic concepts since it will be developed and continuously updated with the advice of a community of nannofossil fossil experts. Broad use of the database is anticipated since it will be widely available through the Internet and on CD-ROM for use on personal computers that do not require large amounts of memory, costly specialized programs, or additional hardware.
9909436 <br/>Farley<br/><br/>This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an investigation of the uplift history of the Dry Valleys segment of the Transantarctic Mountains. The overall goal is to further constrain the exhumation history of the Transantarctic Mountains by using the newly developed apatite (U-Th)/He dating method on samples collected in vertical profiles. This approach, combined with existing apatite fission track information will constrain the rate and patterns of exhumation across the Transantarctic Mountains since their inception as a rift-flank uplift in the early Cenozoic.<br/><br/>This project will complement other projects and build on previous interpretations of the exhumation and tectonic history determined using apatite fission track thermochronology. It will bridge the gap between information on erosion rates determined from fission track thermochronology and from cosmogenic surface exposure dating and integrate the exhumation history of the mountains with their landscape evolution. As such, the results from this project will address an outstanding problem in Antarctic science; namely the stability of the East Antarctic Ice Sheet, and the timing of the transition from a "warm" dynamic ice sheet to a cold polar ice sheet. Highly relevant to this issue is the landscape evolution of the Transantarctic Mountains because many diverse lines of evidence for the rate of landscape evolution have been used to argue for a dynamic ice sheet up until either the Pliocene (the "dynamic" ice sheet model) or the middle Miocene (the "stable" ice sheet model). Understanding the past stability or dynamic fluctuations of the East Antarctic ice sheet with respect to the climate record is, of course, important for understanding how the present ice sheet may respond to global warming.<br/><br/>The specific objective of this project is to determine apatite (U-Th)/He age versus elevation trends for a number of vertical profiles from locations within the Transantarctic Mountain front and across the structural grain of the range. Fission track data already exist for all of these profiles, with apatite fission track ages ranging from 150-30 Ma. The greater precision of the (U-Th)/He technique and the fact it records information at lower temperatures (closure temperature of ~70 degrees Celsius; limits of 40-85 degrees Celsius for the He partial retention zone) will allow examination of the exhumation history of the TAM in more detail from ca 130 Ma to ~20 Ma. Another facet is to examine areas where Cretaceous exhumation is recorded and areas where the fission track profiles indicate periods of thermal and tectonic stability and minimal erosion throughout the Cretaceous. The variation of timing of the onset of more rapid exhumation accompanying uplift and formation of the Transantarctic Mountains in the early Cenozoic will also be examined.
Encarnaci_n OPP 9615398 Abstract Basement rocks of the Transantarctic Mountains are believed to record a change in the paleo-Pacific margin of Gondwana from a rifted passive margin to a tectonically active margin (Ross orogen). Recent hypothesis suggest that the passive margin phase resulted from Neoproterozoic rifting of Laurentia from Antarctica ("SWEAT" hypothesis). The succeeding active margin phase (Ross orogeny) was one of several tectonic events ("Pan African" events) that resulted from plate convergence/transpression that was probably a consequence of the assembly of components of the Gondwana supercontinent. Although these basement units provide one of the keys for understanding the break up and assembly of these major continental masses, few precise ages are available to address the following important issues: (1) Is there any pre-rift high-grade cratonal basement exposed along the Transantarctic Mountains, and what is/are its precise age? Is this age compatible with a Laurentia connection? (2) What is the age of potential rift/passive margin sediments (Beardmore Group) along the Queen Maud Mountains sector of the orogen? (3) What is the relative and absolute timing of magmatism and contractional deformation of supracrustal units in the orogen? Was deformation diachronous and thus possibly related to transpressional tectonics, or did it occur in a discrete pulse that is more compatible with a collision? How does contraction of the orogen fit in with emplacement of voluminous plutonic and volcanic rocks? The answers to these questions are central to understanding the kinematic evolution of this major orogenic belt and its role in Neoproterozoic-Early Paleozoic continental reconstructions and plate kinematics. Hence, this award supports funding for precise U-Pb dating, using zircon, monazite, baddeleyite, and/or titanite from a variety of magmatic rocks in the Queen Ma ud Mountains, which can address the foregoing problems. In addition to the issues above, precise dating of volcanics that are interbedded with carbonates containing probable Middle Cambrian fauna could potentially provide a calibration point for the Middle Cambrian, which will fill a gap in the absolute time scale for the early Paleozoic.
Major portions of the Antarctic Ice Sheet float in the surrounding ocean, at the physical and intellectual boundaries of oceanography and glaciology. These ice shelves lose mass continuously by melting into the sea, and periodically by the calving of icebergs. Those losses are compensated by the outflow of grounded ice, and by surface accumulation and basal freezing. Ice shelf sources and sinks vary on several time scales, but their wastage terms are not yet well known. Reports of substantial ice shelf retreat, regional ocean freshening and increased ice velocity and thinning are of particular concern at a time of warming ocean temperatures in waters that have access to deep glacier grounding lines.<br/>This award supports a study of the attrition of Antarctic ice shelves, using recent ocean geochemical measurements and drawing on numerical modeling and remote sensing resources. In cooperation with associates at Columbia University and the British Antarctic Survey, measurements of chlorofluorocarbon, helium, neon and oxygen isotopes will be used to infer basal melting beneath the Ross Ice Shelf, and a combination of oceanographic and altimeter data will be used to investigate the mass balance of George VI Ice Shelf. Ocean and remote sensing observations will also be used to help refine numerical models of ice cavity circulations. The objectives are to reduce uncertainties between different estimates of basal melting and freezing, evaluate regional variability, and provide an update of an earlier assessment of circumpolar net melting.<br/>A better knowledge of ice shelf attrition is essential to an improved understanding of ice shelf response to climate change. Large ice shelf calving events can alter the ocean circulation and sea ice formation, and can lead to logistics problems such as those recently experienced in the Ross Sea. Broader impacts include the role of ice shelf meltwater in freshening and stabilizing the upper ocean, and in the formation of Antarctic Bottom Water, which can be traced far into the North Atlantic. To the extent that ice shelf attrition influences the flow of grounded ice, this work also has implications for ice sheet stability and sea level rise.
9725882 Raymond This award is for support for a program of surface-based radio echo sounding to examine the geometry of the internal layering and the presence or absence of thawed zones outside the margins of active Ice Streams B and E and across the flow band feeding Ice Stream D. Melting in the marginal shear zone and/or on the bed outside an ice stream relates to the amount of support of the ice stream from the sides compared to the bed and the conditions that limit expansion of its width. Radar observations will be extended over the crest of adjacent inter-ice-stream ridges (B/C and D/E) and areas next to the flow band in the onset of D. The purpose is to examine internal layering indicative of the histories of these areas adjacent to ice streams and to determine whether ice streams have expanded into these presently stable areas in the past. These goals concerning the physical controls and history of ice stream width relate to how the discharge of ice streams has changed in the past and could change in the future to affect sea level.
Anandakrishnan, Sridhar; Alley, Richard; Voigt, Donald E.
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This award supports a project to investigate the new-found, startling sensitivity of two major West Antarctic ice streams to tidal oscillations to learn the extent and character of the effect and its ramifications for future ice-stream behavior. Ice streams D, C and Whillans (B) all show strong but distinct tidal signals. The ice plain of Whillans is usually stopped outright, forward motion being limited to two brief periods each day, at high tide and on the falling tide. Motion events propagate across the ice plain at seismic wave velocities. Near the mouth of D, tides cause a diurnal variation of about 50% in ice-stream speed that propagates upglacier more slowly than on Whillans, and seismic data show that C experiences even slower upglacier propagation of tidal signals. Tidal influences are observed more than 100 km upglacier on C, more than 40 km upglacier on D, and may be responsible for fluctuations in basal water pressure reported 400 km upstream on Whillans, nearly the full length of the ice stream. During the first year, the spatial extent of this behavior will be measured on Whillans Ice Stream and ice stream D by five coordinated seismic and GPS instrument packages at 100-km spacing on each ice stream. These packages will be deployed by Twin Otter at sites selected by review of satellite imagery and will operate autonomously through a combination of solar and battery power for two lunar cycles to study the sensitivity of the ice stream motion to spring and neap tides. Additionally, existing data sets will be examined further for clues to the mechanisms involved, and preliminary models will be developed to reconcile the seemingly contrasting behaviors observed on the ice streams. The second and third field seasons will examine in greater detail the tidal behavior of Whillans (year 2) and D (year 3). Work will especially focus on detailed study of at least one source area for events on Whillans, assuming that source areas inferred from preliminary data remain active. Vertical motions have not yet been detected, but differential GPS will increase our detection sensitivity. Seismic instrumentation will greatly increase temporal resolution and the ability to measure the propagation speed and any spatial heterogeneity. Modeling will be refined as more is learned from the field experiments. The project should yield numerous broader impacts. The improved knowledge of ice-stream behavior from this study will contribute to assessment of the potential for rapid ice-sheet change affecting global sea level with societal consequences. Results will be disseminated through scientific publication and talks at professional meetings, as well as contacts with the press, university classes taught by the PIs, visits to schools and community groups, and other activities. Two graduate students will be educated through the project.
This award supports a project to improve understanding of post-glacial retreat and thinning of the Siple Coast region. Research has shown how age-depth relationships from ice cores can be extrapolated over wide areas by tracking continuous radar layers. By comparing radar-derived timescales with one from a model of ice- flow, glacial conditions over regional scales were inferred. High-resolution radar profiles have been collected across most of the inter-stream ridges in the Siple Coast region, and an age- depth relationship has been established from the Siple Dome ice core. Application of the techniques used by others is problematic because the ice streams that surround Siple Dome have disrupted the continuity of the internal layers. A specific goal of this project is to search for other less direct ways to match radar layers between unconnected profiles. The correspondence between radar reflections and measurements of electrical conductivity and volcanic sulfates along the Siple Dome core will be investigated. The strategy is to search for distinctive patterns in the echoes that will facilitate layer matching. Preliminary results are encouraging: at least four distinct echoes at Siple Dome can be matched to spikes in the conductivity profile and the signature of one (at 210m depth, which is ~1,800 yrs BP) closely resembles that of a layer at ~200m on Ridge BC. Matching layers (and hence timescales) across the ice streams will allow reconstruction of spatial patterns of past flow, thinning and accumulation rate in the Siple Coast region, which is needed to predict future possible changes of the West Antarctic Ice Sheet. Data necessary for the proposed work are already available; additional fieldwork in Antarctica is not required. The project will take two years to complete and will provide core education for a doctoral student in Earth and Space Sciences, with an emphasis on radioglaciology.
This award supports a comprehensive study of rift growth on the Amery Ice Shelf (AIS), East Antarctica, using a combination of in situ and remote sensing data with numerical modeling. On the AIS there is an opportunity to examine an active rift system, which is a combination of two longitudinal-to-flow rifts, which originated at the ice shelf front in the suture zones between merging flowbands, and two transverse-to-flow rifts, which formed at the tip of the western longitudinal rift around 1996. Work in progress indicates that these two transverse rifts do not propagate independently of each other, but somehow grow more or less synchronously. The longest of these rifts-the eastern one-grows at an average rate of about 8m per day. When it meets the eastern longitudinal rift, an event that is expected to occur during the funding period (mid-2006), an iceberg (~30 x 30 km) will calve. Based on observations collected over the past half century, there is reason to believe that such a calving event may be a part of a repetitive sequence. In the proposed project, the expansion and propagation of both transverse rifts will be studied using a network of GPS and seismometers deployed around the tip of each transverse rift. Once the iceberg has calved, the effects its calving has on the dynamics of the ice shelf and the activation of previously inactive rifts will also be studied. Insofar as the rate of calving activity is a proxy for local and regional climate conditions, a broader impact of the proposed work is directly related to the socio-environmental topics of climate and sea-level change. The subject of iceberg calving has a history of sparking a great deal of interest from the media and the public alike, especially since the recent large calving events from the Ross and Ronne ice shelves and the remarkably sudden break-up of the Larsen Ice Shelf. The work will involve at least one graduate student, and will involve a partnership with a local charter high school. Field work, instrument deployments, and data collection and analysis will be conducted in close collaboration with the Australian Antarctic Division and the University of Tasmania, which has been a crucial component of research conducted to date. This project will also make use of the Scripps Institution of Oceanography Visualization Center as a means to display results to faculty and researchers of the University of California, San Diego, undergraduate and graduate students, to school children and their teachers, and ultimately to the visiting public.
This project determines the recent history of the West Antarctic Ice Sheet (WAIS) through a multidisciplinary study of the seabed in the Ross Sea of Antarctica. WAIS is perhaps the world's most critical ice sheet to sea level rise dut to near-future global warming. its history has been a key focus for the past decade, but there are significant questions as to whether WAIS was stable during the last glacial maximum--about 20,000 years ago--or undergoing advance and retreat. This project studies grounding zone translantions in Eastern Basin to constrain WAIS movements using a multidisciplinary approach that integrates multibeam bathymetry, seismic stratigraphy, sedimentology, diatom biostratigraphy, radiocarbon dating, 10Be concentration analyses, and numerical modeling.<br/><br/>The broader impacts include improving society's understanding of sea level rise linked to global warming; postdoctoral, graduate, and undergraduate education; and expanding the participation of groups underrepresented in Earth sciences through links with LSU's Geoscience Alliance to Encourage Minority Participation.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a collaborative research project between the Saint Mary's College of California, the South Dakota School of Mines and technology, and the Argentine Antarctic Institute (Instituto Antartico Argentino or IAA) to investigate the Late Mesozoic vertebrate paleontology of the James Ross Basin in the Antarctic Peninsula region. The Campanian through the Maastrichtian ages (80 to 65 million years ago) is an important time interval concerning vertebrate biogeography (i.e. dispersals and separations due to moving landmasses) and evolution between Antarctica and other Southern Hemisphere continents (including India, i.e. Gondwana). Moreover, the dispersal of terrestrial vertebrates (i.e. dinosaurs and marsupial mammals) from North America to Antarctica and beyond (e.g. Australia) via Patagonia and the Antarctic Peninsula, as well as the dispersal of modern birds from Antarctica northward are important unresolved questions in paleontology. These dispersal events include vertebrates not only in the terrestrial realms, but also in marine settings. Both widely distributed and localized marine reptile species have been identified in Antarctica, creating questions concerning their dispersal in conjunction with the terrestrial animals.<br/><br/>The Antarctic Peninsula and Patagonia represent the western-most portion of the Weddellian Paleobiogeographic Province, a region that extends from Patagonia through the Antarctic Peninsula and western Antarctica to Australia and New Zealand. Within this province lie the dispersal routes for interchanges of vertebrates between South America and: 1) Madagascar and India, and 2) Australia. As the result of previous work by the principal investigators, it is postulated that an isthmus between more northern South America and the Antarctic craton has served to bring typical North American dinosaurs, such as hadrosaurs (duck-billed dinosaurs) and presumably marsupials traveling overland, while marine reptiles swam along coastal waters, to Antarctica in the latest Cretaceous. Finally, this region has served as the cradle for the evolution, if not the origin, for groups of modern birds, and evolution of a suite of typical southern hemisphere plants.<br/><br/>In order to confirm and expand upon these hypotheses, investigations into the latest Cretaceous deposits of the James Ross Basin, Antarctica Peninsula must be continued. The Cape Lamb and Sandwich Bluff geological units, of the Lopez de Bertodano Formation in the James Ross Basin along the eastern Antarctic Peninsula, exhibit a mixture of marine and terrestrial deposits. The following vertebrates have been recovered from these sedimentary deposits during previous field seasons: plesiosaur and mosasaur marine reptiles; plant eating dinosaurs; a meat eating dinosaur; and a variety of modern bird groups, including shorebirds, wading birds and lagoonal birds.<br/><br/>This project will undertake new fieldwork to recover new specimens in order to test biogeographic and evolutionary hypotheses concerning Late Cretaceous vertebrates in Gondwana. Fieldwork is planned in January 2002 and 2003 to explore the eastern slopes of Cape Lamb, Sandwich Bluff and False Island Point on Vega Island, and the Santa Marta Cove area of James Ross Island.<br/><br/>This research will result in important new insights about the evolution and geographic dispersal of several vertebrate species. The results are important to understanding the development and evolution of life on Earth.<br/><br/>This is a collaborative research project with Argentinean scientists from the IAA and it continues a productive collaboration that began in 1995. In addition, collaboration with vertebrate paleontologists from the Museo de La Plata, both in the field and at our respective institutions in Argentina and in the United States, will continue.
Ice streams are believed to play a major role in determining the response of their parent ice sheet to climate change, and in determining global sea level by serving as regulators on the fresh water stored in the ice sheets. Ice streams are characterized by rapid, laterally confined flow which makes them uniquely identifiable within the body of the more slowly and more homogeneously flowing ice sheet. But while these characteristics enable the identification of ice streams, the processes which control ice-stream motion and evolution, and differences among ice streams in the polar regions, are only partially understood. Understanding the relative importance of lateral and basal drags, as well as the role of gradients in longitudinal stress, is essential for developing models for future evolution of the polar ice<br/>sheets. In this project, physical statistical models will be used to explore the processes that control ice-stream flow, and to compare these processes between seemingly different ice-stream systems. In particular, Whillans Ice Stream draining into the Ross Ice Shelf, will be compared with Recovery and RAMP glaciers draining into the Ronne-Filchner Ice Shelf, and the Northeast Ice Stream in Greenland. Geophysical models lie at the core of the approach, but are embellished by modeling various components of variability statistically. One important component comes from the uncertainty in observations on basal elevation, surface elevation, and surface velocity. In this project new observational data collected using remote-sensing techniques will be used. The various components, some of which are spatial, are combined hierarchically using Bayesian statistical methodology. All these components will be combined mathematically into a physical statistical model that yields the posterior distribution for basal, longitudinal, and lateral stress fields, and velocity fields, conditional on the data. Inference based on this distribution will be carried out via Markov chain Monte Carlo techniques, to obtain estimates of these unknown fields along with uncertainty measures associated with them.
9814816<br/>Blankenship<br/><br/>This award supports a four year project to develop of better understanding the ice streams of the Ross Sea Embayment (A--F) which drain the interior West Antarctic Ice Sheet (WAIS) by rapidly moving vast quantities of ice to the calving front of the Ross Ice Shelf. The project will examine the role of these ice streams as buffers between the interior ice and the floating ice shelves. The reasons for their fast flow, the factors controlling their current grounding-line-, margin-, and head-positions are crucial to any attempt at modeling the WAIS system and predicting the future of the ice sheet. For the Antarctic ice streams of the Siple Coast, the transition from no-sliding (or all internal deformation) to motion dominated by sliding is defined as the "onset-region". To fully understand (and adequately model) the WAIS, this onset region must be better understood. The lateral margins of the ice streams are also a transition that need better explanation. Hypotheses on controls of the location of the onset region range from the "purely-glaciologic" to the "purely-geologic. Thus, to model the ice sheet accurately, the basal boundary conditions (roughness, wetness, till properties) and a good subglacial geologic map, showing the distribution, thickness, and properties of the sedimentary basins, are required. These parameters can be estimated from seismic, radar, and other geophysical methods. The transition region of ice stream D will be studied in detail with this coupled geophysical experiment. In addition, selected other locations on ice streams C & D will be made, to compare and contrast conditions with the main site on ice stream D. Site-selection for the main camp will be based on existing radar, GPS, and satellite data as well as input from the modeling community.
This award supports a project to significantly improve our understanding of how Taylor Glacier flows and responds to climate changes. Taylor Glacier drains the Taylor Dome region of the East Antarctic Ice Sheet and terminates in Taylor Valley, one of the Dry Valleys of Victoria Land. It provides a crucial and unique link between two intensively studied Antarctic environments: the Taylor Dome, from which a 130 kyr ice core paleoclimate record has recently been extracted, and the Dry Valleys, a pivotal Long-Term Ecological Research (LTER) site and a focus of research on geomorphology and glacial geology. The proposed work will thus make an important contribution to ongoing efforts to exploit the Taylor Dome - Dry Valleys system to build a uniquely comprehensive view of regional long-term environmental changes. The proposed work has two complementary components: field research and numerical modelling. Two field seasons will be used to measure velocity, surface strain rate, mass balance, ice thickness, glacier bed reflectance, and subglacial topography, along a nearly complete longitudinal transect of the Taylor Glacier, and along select cross-valley transects. This information will be used to constrain numerical models of ice and heat flow for the Taylor Dome - Taylor Glacier system. These calibrated models will be used to analyze the time-dependent response of the Taylor Glacier to climate changes. The synthesis of results will be aimed to improve understanding of the glacial geomorphology of Taylor Valley, and to illuminate impacts on the Taylor Valley lakes ecosystem. The project will have a major role in furthering the careers of a doctoral-level graduate student and a post-doctoral researcher.
Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an interdisciplinary study of fluvial sediments in Antarctica for evidence of what caused the greatest of all mass extinctions in the history of life at the Permian-Triassic boundary. This boundary was, until recently, difficult to locate and thought to be unequivocally disconformable in Antarctica. New studies, particularly of carbon isotopic chemostratigraphy and of paleosols and root traces as paleoecosystem indicators, together with improved fossil plant, reptile and pollen biostratigraphy, now suggest that the precise location of the boundary might be identified and have led to local discovery of iridium anomalies, shocked quartz, and fullerenes with extraterrestrial noble gases. These anomalies are associated with a distinctive claystone breccia bed, similar to strata known in South Africa and Australia, and taken as evidence of deforestation. There is already much evidence from Antarctica and elsewhere that the mass extinction on land was abrupt and synchronous with extinction in the ocean. The problem now is what led to such death and destruction. Carbon isotopic values are so low in these and other Permian-Triassic boundary sections that there was likely to have been some role for catastrophic destabilization of methane clathrates. Getting the modeled amount of methane out of likely reservoirs would require such catastrophic events as bolide impact, flood-basalt eruption or continental-shelf collapse, which have all independently been implicated in the mass extinction and for which there is independent evidence. Teasing apart these various hypotheses requires careful re-examination of beds that appear to represent the Permian-Triassic boundary, and search for more informative sequences, as was the case for the Cretaceous-Tertiary boundary. This collaborative research on geochemistry and petrography of boundary beds and paleosols (by Retallack), on carbon isotopic variation through the boundary interval (by Jahren), and on fullerenes, iridium and helium (by Becker) is designed to test these ideas about the Permian-Triassic boundary in Antarctica and to shed light on processes which contributed to this largest of mass extinctions on Earth. Fieldwork for this research will be conducted in the central Transantarctic Mountains and in Southern Victoria Land with an initial objective of examining the stratigraphic sequences for continuity across the boundary. Stratigraphic continuity is a critical element that must exist for the work to be successful. If fieldwork indicates sufficiently continuous sections, the full analytical program will follow fieldwork.
The summit crater of Mt. Moulton, in West Antarctica, contains a 600-m thick horizontally-exposed section of ice with intercalated tephra layers from nearby Mt Berlin. Argon-40/Argon-39 dating of the thick, near-source tephra indicates that the age of the horizontal ice section ranges between 15,000 and 492,000 years. Thus, the Mt Moulton site offers an unparalleled repository of ancient West Antarctic snow and trapped air that can be used to investigate West Antarctic climate over much of the past 500,000 years. The planar nature and consistent dips of the tephra layers suggests that, although the ice section has thinned, it is otherwise undeformed. The Mt. Moulton site was visited during the 1999/2000 field season, at which time a horizontal ice core representing approximately 400 meters of ice was collected, ranging in age from 15,000 to older than 480,000 years. In addition to this horizontal core, samples of ice at a range of depths were collected in order to test the quality of the climate record in the ice. Forty tephra layers intercalated in the ice were also collected in order to provide chronology for the ice section. The results of this first effort are extremely encouraging. Based on the d?18 O of ice, for example, there is clearly a useable record of past climate at Mt. Moulton extending back beyond 140,000 years. There is work to do, however, to realize the full potential of this horizontal ice core. The elemental and isotopic composition of trapped gases suggest some contamination with modern air, for example. As gas cross-dating of ice cores is the current standard by which climate records are intercompared, we need to understand why and how the gas record is compromised before adding Moulton to our arsenal of ice core paleoclimate records. This award supports a collaborative effort between three institutions with following objectives: 1) to evaluate more thoroughly the integrity of the climatic record through shallow drilling of the blue ice area, as well as the snow field upslope from the blue ice; 2) to improve the radioisotopic dating of specific tephra layers; 3) to obtain baseline information about modern snowfall deposition, mean annual temperature, and wind pumping around the summit of Mt. Moulton; and 4) to study how firn densification differs when surface accumulation changes from net accumulation to net ablation.
This award supports a program of field surveys of an area within the large, well-developed megadune field southeast of Vostok station. The objectives are to determine the physical characteristics of the firn across the dunes, including typical climate indicators such as stable isotopes and major chemical species, and to install instruments to measure the time variation of near-surface wind and temperature with depth, to test and refine hypotheses for megadune formation. Field study will consist of surface snowpit and shallow core sampling, ground penetrating radar (GPR) profiling, GPS topographic and ice motion surveys, AWS installation, accumulation/ ablation measurements, subsurface temperature, and firn permeability studies. Field work in two successive seasons is proposed. Continent-wide remote sensing studies of the dunes will be continued, using the new group of instruments that are now, or will shortly be available (e.g., MODIS, MISR, GLAS, AMSR). The earlier study of topographic, passive microwave, and SAR characteristics will be extended, with the intent of determining the relationships of dune amplitude and wavelength to climate parameters, and further development of models of dune formation. Diffusion, ventilation, and vapor transport processes within the dune firn will be modeled as well. A robust program of outreach is planned and reporting to inform both the public and scientists of the fundamental in-situ and remote sensing characteristics of these uniquely Antarctic features will be an important part of the work. Because of their extreme nature, their broad extent, and their potential impact on the climate record, it is important to improve our current understanding of these. Megadunes are a manifestation of an extreme terrestrial climate and may provide insight on past terrestrial climate, or to processes active on other planets. Megadunes are likely to represent an end-member in firn diagenesis, and as such, may have much to teach us about the processes involved.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the Transantarctic Mountains and an adjacent region of East Antarctica. The East Antarctic shield is one of Earth's oldest and largest cratonic assemblies, with a long-lived Archean to early Paleozoic history. Long-standing interest in the geologic evolution of this shield has been rekindled over the past decade by tectonic models linking East Antarctica with other Precambrian crustal elements in the Rodinia and Gondwanaland supercontinents. It is postulated that the Pacific margin of East Antarctica was rifted from Laurentia during late Neoproterozoic breakup of Rodinia, and it then developed as an active plate boundary during subsequent amalgamation of Gondwanaland in the earliest Paleozoic. If true, the East Antarctic shield played a key role in supercontinent transformation at a time of global changes in plate configuration, terrestrial surficial process, sea level, and marine geochemistry and biota. A better understanding of the geological evolution of the East Antarctic shield is therefore critical for studying Precambrian crustal evolution in general, as well as resource distribution, biosphere evolution, and glacial and climate history during later periods of Earth history. Because of nearly complete coverage by the polar ice cap, however, Antarctica remains the single most geologically unexplored continent. Exposures of cratonic basement are largely limited to coastal outcrops in George V Land and Terre Adelie (Australian sector), the Prince Charles Mountains and Enderby Land (Indian sector), and Queen Maud Land (African sector), where the geology is reasonably well-known. By contrast, little is known about the composition and structure of the shield interior. Given the extensive ice cover, collection of airborne geophysical data is the most cost-effective method to characterize broad areas of sub-ice basement and expand our knowledge of the East Antarctic shield interior. <br/><br/>This project will conduct an airborne magnetic survey (coupled with ground-based gravity measurements) across an important window into the shield where it is exposed in the Nimrod Glacier area of the central Transantarctic Mountains. Specific goals are to:<br/>1. Characterize the magnetic and gravity signature of East Antarctic crustal basement exposed at the Ross margin (Nimrod Group),<br/>2. Extend the magnetic data westward along a corridor across the polar ice cap in order to image the crust in ice-covered areas,<br/>3. Obtain magnetic data over the Ross Orogen in order to image the ice-covered boundary between basement and supracrustal rocks, allowing us to better constrain the geometry of fundamental Ross structures, and<br/>4. Use the shape, trends, wavelengths, and amplitudes of magnetic anomalies to define magnetic domains in the shield, common building blocks for continent-scale studies of Precambrian geologic structure and evolution.<br/><br/>High-resolution airborne magnetic data will be collected along a transect extending from exposed rocks of the Nimrod Group across the adjacent polar ice cap. The Nimrod Group represents the only bona fide Archean-Proterozoic shield basement exposed for over 2500 km of the Pacific margin of Antarctica. This survey will characterize the geologically well-known shield terrain in this sector using geophysical methods for the first time. This baseline over the exposed shield will allow for better interpretation of geophysical patterns in other ice-covered regions and can be used to target future investigations. In collaboration with colleagues from the BGR (Germany), a tightly-spaced, "draped" helicopter magnetic survey will be flown during the 2003-04 austral summer, to be complemented by ground measurements of gravity over the exposed basement. Data reduction, interpretation and geological correlation will be completed in the second year. This project will enhance the education of students, the advancement of under-represented groups, the research instrumentation of the U.S. Antarctic Program, partnerships between the federal government and institutions of higher education, and cooperation between national research programs. It will benefit society through the creation of new basic knowledge about the Antarctic continent, which in turn may help with applied research in other fields such as the glacial history of Antarctica.
Roy, Martin; Hemming, Sidney R.; Goldstein, Steven L.; Van De Flierdt, Christina-Maria
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This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the sediment core from the Southern Ocean for paleoenvironmental research. The polar regions are susceptible to the largest changes in climate and are among the least accessible places on Earth. Current concern about the instability of the West Antarctic Ice Sheet has heightened awareness of the vulnerability of polar regions. This proposal seeks to gain a basic understanding of the isotopic characteristics of terrigenous sediment sources derived from Antarctica in the Holocene and Last Glacial Maximum, and their dispersal into the Southern Ocean. Terrigenous clastic sediments are brought to the ocean from continental sources via rivers, ice and wind, and distributed within the ocean by surface and deep currents. At present there are virtually no isotopic data on circumpolar detritus, save a few strontium (Sr) isotopic ratios in the Atlantic sector. This project will fill part of this gap. From the large range in geological ages of crustal provinces of Antarctica, we would predict that there are large isotopic differences in detritus around the continent. The main objectives are to (1) characterize the strontium-neodymium-lead-argon (Sr-Nd-Pb-Ar) isotope compositions of sediment sources derived from Antarctica, (2) to identify the composition and source ages of major ice rafted detritus (IRD) contributions by analyzing individual grains of hornblende and feldspar in conjunction with bulk isotopic analysis, and (3) track sediment dispersal into the Antarctic Circumpolar Current (ACC) during the Holocene and Last Glacial Maximum.<br/><br/>Because of the paucity of circumpolar data, this research necessarily has a large exploratory component. Consequently, it will provide a basic database for future studies. Nevertheless there are important hypothesis-driven questions that will be addressed in this primary pass. Can lessons learned in North Atlantic IRD studies be applied toward understanding the history of Antarctic ice sheets? Can the large geological variability around the Antarctic margin be treated as a series of natural tracer injections into the ACC, and thus characterize its trajectory, speed, and interaction with other current systems today and in the past? The proposed study is motivated by an exciting set of results from the South Atlantic, showing that detrital Sr isotope ratios are a sensitive current tracer in that region. This research should serve a basic need across many Earth Science disciplines if the use of long-lived radiogenic isotopes (Sr-Nd-Pb-Ar) as tracers of marine sediment sources is successful in elucidating processes related to changing climatic conditions. The results of this study will fill a basic gap in our knowledge of an important region of the Earth. At the same time, it will provide an essential basis for attempting reconstruction of the ACC during the LGM, as well as for future studies of Antarctic geology, ice sheet history, and the Southern Ocean circulation.
9316564 Mayewski This award is for support for a three year program to provide a high resolution record of the Antarctic climate through the acquisition, analysis, and interpretation of records of atmospheric chemical deposition taken from three ice cores located at sites within or immediately adjacent to the Ross Ice Drainage System (RIDS). These cores include one from Taylor Dome, and two from West Antarctic locations identified as potential deep drilling sites for the WAISCORES program. Collection of the two West Antarctic cores is intended to be a lightweight dry-drilling operation to depths of ~ 200 m, which will provide records of > 2 kyr. Glaciochemical analyses will focus on the major cations and anions found in the antarctic atmosphere, plus methanesulfonic acid and selected measurements of the hydrogen ion, aluminum, iron, and silica. These analyses, and companion stable isotope and particle measurements to be carried out by other investigators require < 7% by volume of each core, leaving > 90% for other investigators and storage at the U.S. National Ice Core Laboratory. These records are intended to solve a variety of scientific objectives while also providing spatial sampling and reconnaissance for future U.S. efforts in West Antarctica. ***
Elliot, David; Bell, Robin; Blankenship, Donald D.; Brozena, J. M.; Finn, C. A.; Hodge, S. M.; Kempf, Scott D.; Behrendt, J. C.; Morse, David L.; Peters, M. E.; Studinger, Michael S.
This award will support a combined airborne radar and aeromagnetic survey of two 220 x 330 km regions between the Transantarctica Mountains and Marie Byrd Land during the 1990-91 and 1991-92 field seasons. These efforts will address significant problems identified in the Ross Transect Zone (RTZ) by the National Academy of Sciences (1986) report "Antarctic Solid Earth Sciences Research," and by the report to NSF "A Plan for a United States Program to Study the Structure and Evolution of the Antarctic Lithosphere (SEAL)." The surveys will be flown using the NSF/TUD radar and an areomagnetics system mounted in a light aircraft. The grid spacing will be 5 km and navigation will be by radiopositioning. In addition to maps of subglacial topography and magnetic intensity, attempts will be made to reconstruct the position of subglacial diffractors in three dimensions. This reconstruction should give new information about the distribution of escarpments and therefore the tectonic relationships within the region, especially when combined with the magnetic results. These experiments will be conducted by the Byrd Polar Research Center of the Ohio State University and the Water Resources and Geological Divisions of the U.S. Geological Survey.
9980691<br/>Wahlen<br/><br/>This award is for support for three years of funding to reconstruct the atmospheric carbon dioxide (CO2) and carbon-13 isotope (d13C) concentration in ice cores from Antarctica over several climatic periods. Samples from the Holocene, the Last Glacial Maximum (LGM)-Holocene transition and glacial stadial/interstadial episodes will be examined. Samples from the Siple Dome ice core drilled in 1998/99 will be made, in addition to measurements from the Taylor Dome and Vostok ice cores. The major objectives are to investigate the phase relationships between variations in the concentration of atmospheric CO2, its carbon isotope composition, and temperature changes (indicated by 18dO and dD of the ice) during deglaciations as well as across rapid climate change events (e.g. Dansgaard-Oeschger events). This will help to determine systematic changes in the global carbon cycle during and between different climatic periods, and to ascertain if the widely spread northern hemisphere temperature stadial/interstadial events produced a global atmospheric carbon dioxide signal. Proven experimental techniques will be used.
This award is for support for a three year program to investigate the response of ice domes, such as Siple Dome in West Antarctica, to changing boundary conditions, for example as arising from fluctuations in thickness or position of bounding ice streams. A range of models will be used, from simple one-dimensional analytical models to coupled dynamic-thermodynamic flow models, to investigate the response of the ice dome to boundary forcing, and the record that boundary forcing can leave in the ice core record. Using radar, temperature, and ice core data from the currently funded field programs on Siple Dome, and ice flux and thickness values from the map view model as boundary conditions, a flow line across Siple Dome will be studied and possible ranges of time scales, the likely origin of ice near the bed, and the basal temperature conditions that exist now and existed in the past will be determined.The response of internal stratigraphy patterns to climate and dynamic forcing effects will be investigated and observed internal layers from ice cores will be used to infer the forcing history.
This award is for two years of support to perform radar investigations across former shear margins at Roosevelt Island and Ice Stream C in order to measure changes in the configuration and continuity of internal layers and the bed. The broad goal of these investigations is to gain an understanding of ice stream flow and the timing and mechanisms of ice stream shutdown. A high-resolution short-pulse radar system will be used for detailed examination of the uppermost hundred meters of the firn and ice, and a monopulse sounding-radar system will be used to image the rest of the ice column (including internal layers) and the bed. Changes in the shape and continuity of layers will be used to interpret mechanisms and modes of ice stream flow including the possible migration of stagnation fronts and rates of shut-down. Variations in bed reflectivity will be used to deduce basal hydrology conditions across lineations. Accumulation rates deduced from snow pits and shallow cores will be used to estimate near-surface depth-age profiles. Improved understanding of ice stream history opens the possibility of linking changes in the West Antarctic ice sheet with the geologic evidence from Northern Victoria Land and the ocean record of the retreat of the grounding line in the Ross Sea.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research for construction of a long-term record of climate during the late Cretaceous and early Paleogene to assess the annual seasonality in temperature on the coastal margin of Antarctica. Stable isotope and element compositions of well-preserved bivalve shells collected on Seymour Island will be the primary source of data used to reconstruct paleoenvironmental conditions. Seasonal temperature records collected through high-resolution sampling along growth structures in bivalve shells will allow seasonality to be assessed during different climate states and during periods of rapid climate change. In addition, high stratigraphic resolution will enable this project to detect the presence and frequency of short-lived thermal excursions that may have extended to such high latitudes.<br/><br/>To compile a reliable temporal record of paleoclimate, two major avenues of investigation will be undertaken: 1) precise stratigraphic (and therefore, temporal) placement of fossils over a large geographic area will be employed through the use of a graphical technique employing geometric projections; 2) stable isotope and elemental analyses will be performed to derive paleotemperatures and to evaluate diagenetic alteration of shell materials. To provide realistic comparisons of paleotemperatures across stratigraphic horizons, this study will focus on a single taxon, thus avoiding complications due to the mixing of faunal assemblages that have been encountered in previous studies of this region.<br/><br/>The near-shore marine fossil record on Seymour Island provides a unique opportunity to address many questions about the Antarctic paleoenvironment, including the relation between seasonality and different climate states, the influence of climate on biogeographic distribution of specific taxa, the effect of ice-volume changes on the stable isotope record from the late Cretaceous through the Eocene, and the plausibility of high-latitude bottom water formation during this time interval. In particular, information that will be collected concerning patterns of seasonality and the presence (or absence) of short-lived thermal excursions will be extremely valuable to an understanding of the response of high latitude sites during climate transitions from globally cool to globally warm conditions.
9725305 Severinghaus This award supports a project to develop and apply a new technique for quantifying temperature changes in the past based on the thermodynamic principle of thermal diffusion, in which gas mixtures in a temperature gradient become fractionated. Air in polar firn is fractionated by temperature gradients induced by abrupt climate change, and a record of this air is preserved in bubbles in the ice. The magnitude of the abrupt temperature change, the precise relative timing, and an estimate of the absolute temperature change can be determined. By providing a gas-phase stratigraphic marker of temperature change, the phasing of methane (with decadal precision) and hence widespread climate change (relative to local polar temperature changes) can be determined (across five abrupt warming events during the last glacial period).
Kyle OPP 9527329 Abstract The Cape Roberts Project is an international drilling project to obtain a series of cores from the sedimentary strata beneath the sea floor off Cape Roberts in the Ross Sea. The project is a joint venture by scientists from the national Antarctic programs of Germany, Italy, New Zealand, the United Kingdom., Australia, and the United States. Drilling will continuously core a composite section of sediments over 1500 m thick which is expected to represent parts of the time period between 30 and more than 100 million years ago. The principle objectives of this component of the project will be to examine the record of igneous material in the drill core and provide high precision 40Ar/39Ar dates from tephra (volcanic ash) layers, disseminated ash, feldspars and epiclastic volcanic detrital grains to constrain depositional age and provenance of the sediments in the cores. This project will contribute to general geologic logging of the core and will characterize any igneous material using electron microprobe, x-ray fluorescence (XRF) and instrumental neutron activation analysis (INAA) analyses. The presence of alkalic volcanic detritus from the Cenozoic McMurdo Volcanics will constrain the initiation of this phase of volcanism and improve our understanding of the relationship between volcanism and tectonism. The influx of sediments eroded from Jurassic Kirkpatrick Basalts and Ferrar Dolerites will be used to time the unroofing and rates of uplift of the Transantarctic Mountains. Geochemical analyses of core samples will examine the geochemistry and provenance of the sediments.