{"dp_type": "Project", "free_text": "ADS"}
[{"awards": "2142914 Baker, Bill; 2142912 Murray, Alison; 2142913 Tresguerres, Martin", "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 Marine 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. Technical description Marine 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. 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": 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; Hyporheic zone geochemistry of Wales Stream, Taylor Valley, Antarctica; isotopic signature of massive buried ice, eastern Taylor Valley, Antarctica", "datasets": [{"dataset_uid": "601848", "doi": "10.15784/601848", "keywords": "Antarctica; Buried Ice; Cryosphere; Stable Isotopes; Stable Water Isotopes; Taylor Valley", "people": "Gardner, Christopher B.", "repository": "USAP-DC", "science_program": null, "title": "isotopic signature of massive buried ice, eastern Taylor Valley, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601848"}, {"dataset_uid": "601844", "doi": "10.15784/601844", "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"}, {"dataset_uid": "601847", "doi": "10.15784/601847", "keywords": "Antarctica; Cryosphere; Nutrients; Stable Isotopes; Taylor Valley; Trace Elements", "people": "Gardner, Christopher B.", "repository": "USAP-DC", "science_program": null, "title": "Hyporheic zone geochemistry of Wales Stream, Taylor Valley, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601847"}], "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. 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. 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": 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": "2232891 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": null, "datasets": null, "date_created": "Mon, 14 Aug 2023 00:00:00 GMT", "description": "Antarctic animals face tremendous threats as Antarctic ice sheets melt and temperatures rise. About 34 million years ago, when Antarctica began to cool, most species of fish became locally extinct. A group called the notothenioids, however, survived due to the evolution of antifreeze. The group eventually split into over 120 species. Why did this group of Antarctic fishes evolve into so many species? One possible reason why a single population splits into two species relates to sex genes and sex chromosomes. Diverging species often have either different sex determining genes (genes that specify whether an individual\u2019s gonads become ovaries or testes) or have different sex chromosomes (chromosomes that differ between males and females within a species, like the human X and Y chromosomes). We know the sex chromosomes of only a few notothenioid species and know the genetic basis for sex determination in none of them. The aims of this research are to: 1) identify sex chromosomes in species representing every major group of Antarctic notothenioid fish; 2) discover possible sex determining genes in every major group of Antarctic notothenioid fish; and 3) find sex chromosomes and possible sex determining genes in two groups of temperate, warmer water, notothenioid fish. These warmer water fish include groups that never experienced the frigid Southern Ocean and groups that had ancestors inhabiting Antarctic oceans that later adjusted to warmer waters. This project will help explain the mechanisms that led to the division of a group of species threatened by climate change. This information is critical to conserve declining populations of Antarctic notothenioids, which are major food sources for other Antarctic species such as bird and seals. The project will offer a diverse group of undergraduates the opportunity to develop a permanent exhibit at the Eugene Science Center Museum. The exhibit will describe the Antarctic environment and explain its rapid climate change. It will also introduce the continent\u2019s bizarre fishes that live below the freezing point of water. The project will collaborate with the university\u2019s Science and Comics Initiative and students in the English Department\u2019s Comics Studies Minor to prepare short graphic novels explaining Antarctic biogeography, icefish specialties, and the science of this project as it develops. As Antarctica cooled, most species disappeared from the continent\u2019s waters, but cryonotothenioid fish radiated into a species flock. What facilitated this radiation? Coyne\u2019s \u201ctwo rules of speciation\u201d offer explanations for why species diverge: 1) the dysgenic sex in an interspecies hybrid is the one with two different sex chromosomes (i.e., in humans, it would be XY males and not XX females); and 2) \u201csex chromosomes play an outsized role in speciation\u201d. These ideas propel the project\u2019s main hypothesis: new sex chromosomes and new sex determination genes associate with cryonotothenioid speciation events. The main objective of the research is to identify notothenioid sex chromosomes and candidate sex-determination genes in many notothenioid species. The project\u2019s first aim is to identify Antarctic fish sex chromosomes, asking the question: Did new sex chromosomes accompany speciation events? Knowledge gaps include: which species have cryptic sex chromosomes; which have newly evolved sex chromosomes; and which are chromosomally XX/XY or ZZ/ZW. Methods involve population genomics (RAD-seq and Pool-seq) for more than 20 Antarctic cryonotothenioids. The prediction is frequent turnover of sex chromosomes. The project\u2019s second aim is to Identify candidate Antarctic cryonotothenioid sex-determination genes, asking the question: Did new sex-determination genes accompany Antarctic cryonotothenioid speciation events? A knowledge gap is the identity of sex determination genes in any notothenioid. Preliminary data show that three sex-linked loci are in or adjacent to three different candidate sex determination genes: 1) a duplicate of bmpr1ba in blackfin icefish; 2) a tandem duplicate of gsdf in South Georgia icefish; and 3) a transposed duplicate of gsdf in striped notothen. Methods involve annotating the genomic neighborhoods of cryonotothenioid sex linked loci for anomalies in candidate sex genes, sequencing sex chromosomes, and testing sex gene variants by CRISPR mutagenesis in zebrafish. The prediction is frequent turnover of sex determination genes. The project\u2019s third aim is to identify sex chromosomes and sex-determination genes in temperate notothenioids. Basally diverging temperate notothenioids (\u2018basals\u2019) lack identifiable sex chromosomes, consistent with temperature-cued sex determination, and one \u2018basal\u2019 species is a hermaphrodite. The constantly cold Southern Ocean rules out temperature, a common sex determination cue in many temperate fish, favoring genetic sex determination. Some cryonotothenioids re-invaded temperate waters (\u2018returnees\u2019). Knowledge gaps include whether basals and returnees have strong sex determination genes. Methods employ pool-seq. The prediction is that genetic sex determination is weak in basals and that returnees have the same, but weaker, sex-linked loci as their Antarctic sister clade. A permanent exhibit will be established at the Eugene Science Center Museum tentatively entitled: The Antarctic: its fishes and climate change. Thousands of visitors, especially school children will be exposed, to the science of Antarctic ecosystems and the impacts of climate change. The research team will collaborate with the university\u2019s Science and Comics Initiative to produce short graphic novels explaining Antarctic biogeography, icefish specialties, and this project. 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": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Speciation; Southern Ocean; Dragonfish; Antarctica; Plunderfish; Fish; Notothenioid; FISH; Eleginopsioidea; Icefish; MARINE ECOSYSTEMS; Cryonotothenioid; Sub-Antarctic", "locations": "Antarctica; Southern Ocean; Sub-Antarctic", "north": -37.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Postlethwait, John; Desvignes, Thomas", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "ANT LIA: The Role of Sex Determination in the Radiation of Antarctic Notothenioid Fish", "uid": "p0010431", "west": -180.0}, {"awards": "2326960 Doddi, Abhiram", "bounds_geometry": "POLYGON((36 -68,36.9 -68,37.8 -68,38.7 -68,39.6 -68,40.5 -68,41.4 -68,42.3 -68,43.2 -68,44.1 -68,45 -68,45 -68.2,45 -68.4,45 -68.6,45 -68.8,45 -69,45 -69.2,45 -69.4,45 -69.6,45 -69.8,45 -70,44.1 -70,43.2 -70,42.3 -70,41.4 -70,40.5 -70,39.6 -70,38.7 -70,37.8 -70,36.9 -70,36 -70,36 -69.8,36 -69.6,36 -69.4,36 -69.2,36 -69,36 -68.8,36 -68.6,36 -68.4,36 -68.2,36 -68))", "dataset_titles": null, "datasets": null, "date_created": "Sat, 20 May 2023 00:00:00 GMT", "description": "This international collaboration between the University of Colorado, the University of Kyoto, and the National Institute of Polar Research in Tokyo, will investigate the sources of atmospheric turbulence in coastal Antarctica. Strong winds forced against terrain produce waves called atmospheric gravity waves, which can grow in amplitude as they propagate to higher altitudes, becoming unstable, breaking, and causing turbulence. Another source of turbulence is shear layers in the atmosphere, where one layer of air slides over another, resulting in Kelvin-Helmholtz Instabilities. Collectively, both play important roles in accurately representing the Antarctic climate in weather prediction models. Collecting new turbulence observations in these remote southern high latitudes will improve wind and temperature forecasts of the Antarctic climate. This project will observe gravity wave and shear-induced turbulence dynamics by deploying custom high-altitude balloon systems in coordination and collaboration with a powerful remote sensing radar and multiple long-duration balloons during an observational field campaign at the Japanese Antarctic Syowa station. This research is motivated by the fact that the sources representing realistic multi-scale gravity wave (GW) drag, and Kelvin-Helmholtz Instability (KHI) dynamics, along with their contributions to momentum and energy budgets due to turbulent transport/mixing, are largely missing in the current General Circulation Model (GCM) parameterization schemes, resulting in degraded synoptic-scale forecasts at southern high latitudes. This project utilizes high-resolution in-situ turbulence instruments to characterize the large-scale dynamics of 1) orographic GWs produced by katabatic forcing, 2) non-orographic GWs produced by low-pressure synoptic-scale events, and 3) KHI instabilities emerging in a wide range of scales and background environments in the coastal Antarctic region. The project will deploy dozens of low-cost balloon systems equipped with custom in-situ turbulence and radiosonde instruments at the Japanese Syowa station in Eastern Antarctica. Balloon payloads descend slowly from an apogee of 20 km to provide high- resolution, wake-free turbulence observations, with deployment guidance from the PANSY radar at Syowa, in coordination with the LODEWAVE long duration balloon experiment. The combination of in-situ and remote sensing turbulence observations will quantify the structure and dynamics of small-scale turbulent atmospheric processes associated with GWs and KHI, thought to be ubiquitous in polar environments but rarely observed. Momentum fluxes and turbulence dissipation rates measured over a wide range of scales and background environments will provide datasets to validate current GCM parameterizations for atmospheric GW drag and turbulence diffusion coefficients in the lower and middle atmospheres at southern high latitudes, increasing our understanding of these processes and their contribution to Antarctic circulation and climate. 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": 45.0, "geometry": "POINT(40.5 -69)", "instruments": null, "is_usap_dc": true, "keywords": "TURBULENCE; ATMOSPHERIC WINDS; VERTICAL PROFILES; ATMOSPHERIC PRESSURE; HUMIDITY; Syowa Station", "locations": "Syowa Station", "north": -68.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Doddi, Abhiram; Lawrence, Dale", "platforms": null, "repositories": null, "science_programs": null, "south": -70.0, "title": "RAPID: In-situ Observations to Characterize Multi-Scale Turbulent Atmospheric Processes Impacting Climate at Southern High Latitudes", "uid": "p0010420", "west": 36.0}, {"awards": "2135185 Resing, Joseph; 2135184 Arrigo, Kevin; 2135186 Baumberger, Tamara", "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": "Phytoplankton blooms throughout the world\u2019s oceans support critical marine ecosystems and help remove carbon dioxide (CO2) from the atmosphere. Traditionally, it has been assumed that phytoplankton blooms in the Southern Ocean are stimulated by iron from either nearby land 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 carbon in the deep ocean. Our proposed work will uncover the importance of hydrothermal activity in stimulating a large phytoplankton bloom 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 carbon cycle in the Southern Ocean, which appears to trigger local hotspots of biological activity which are a potential 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 PhD 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. 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 sea surface height (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. 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": 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 Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences; Antarctic Integrated System Science", "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": "2218996 Collins, Kristina", "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": "Magnetic field variations on the Earth\u2019s surface can be used to remote sense and characterize electrical currents and plasma waves in the near-Earth space environment that can affect technology, for example by inducing currents in power grids. Asymmetries between the space environment in the polar regions of the northern and southern hemispheres can profoundly affect these magnetic field variations. Magnetometers, which measure the strength and direction of magnetic fields, have been installed in the Arctic and Antarctic at opposite ends of the Earth\u2019s magnetic field lines. By looking at data from both sets of magnetometers, researchers can determine whether disturbances in the Earth\u2019s magnetosphere (a region of near-Earth space dominated by the Earth\u2019s magnetic field) caused by the Sun impact the Northern hemisphere, the Southern hemisphere or both, and thus understand the sources of north-south hemisphere asymmetries. Some events that appear in the magnetometer data may be difficult for computers to identify, but easy for people to identify if the data is translated into sound. Researchers will develop a tool for listening to data in a virtual reality environment, so that data from various instruments can be played back, making it easier to explore datasets intuitively. This system will be prototyped using a mixed reality headset for use in both science and education and may be used to analyze data taken at the same time by sensors on the ground and on satellites. This project will examine one particular type of disturbance \u2013 magnetosheath jets \u2013 and its relation to plasma waves by addressing the question \u201cDo magnetosheath jets routinely drive Pc5/Pc6 geomagnetic pulsations?\u201d via the analysis of magnetometer data from geomagnetically conjugate (based on the International Geomagnetic Reference Field, IGRF) Arctic and Antarctic magnetometers. This question will be approached first through traditional plotting and visual analysis, then by presenting datastreams as sound sources situated in a virtual audio environment developed in the Unity game engine and integrated with mixed reality presentation via the Microsoft Hololens platform. This approach will leverage human capabilities for spatial discrimination of sounds to identify geomagnetic pulsations (surface magnetic field variations related to plasma waves in outer space) related to magnetosheath jet events with potentially large north-south hemispheric asymmetries, spatially localized wave activity, and irregular waveforms. The resulting presentation modality will make use of existing repositories of magnetometer data and may potentially be extended to the presentation of synchronous datasets from multiple sensing networks. 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": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "MAGNETIC FIELD", "locations": null, "north": -60.0, "nsf_funding_programs": "Post Doc/Travel; Antarctic Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Collins, Kristina", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "OPP-PRF: Conjugate Experiment to Explore Magnetospheric Phenomena Via Spatial Sonification and Mixed Reality", "uid": "p0010363", "west": -180.0}, {"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": "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": "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": "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"}, {"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": "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"}], "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: 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": "R2R", "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": "1643285 Joughin, Ian; 1643174 Padman, Laurence", "bounds_geometry": "POLYGON((-104 -73,-102.2 -73,-100.4 -73,-98.6 -73,-96.8 -73,-95 -73,-93.2 -73,-91.4 -73,-89.6 -73,-87.8 -73,-86 -73,-86 -73.8,-86 -74.6,-86 -75.4,-86 -76.2,-86 -77,-86 -77.8,-86 -78.6,-86 -79.4,-86 -80.2,-86 -81,-87.8 -81,-89.6 -81,-91.4 -81,-93.2 -81,-95 -81,-96.8 -81,-98.6 -81,-100.4 -81,-102.2 -81,-104 -81,-104 -80.2,-104 -79.4,-104 -78.6,-104 -77.8,-104 -77,-104 -76.2,-104 -75.4,-104 -74.6,-104 -73.8,-104 -73))", "dataset_titles": "Beta Version of Plume Model; Data associated with Ice-Shelf Retreat Drives Recent Pine Island Glacier Speedup and Ocean-Induced Melt Volume Directly Paces Ice Loss from Pine Island Glacier; icepack; Pine Island Basin Scale Model", "datasets": [{"dataset_uid": "200290", "doi": "http://hdl.handle.net/1773/46687", "keywords": null, "people": null, "repository": "Uni. Washington ResearchWorks Archive", "science_program": null, "title": "Data associated with Ice-Shelf Retreat Drives Recent Pine Island Glacier Speedup and Ocean-Induced Melt Volume Directly Paces Ice Loss from Pine Island Glacier", "url": "https://doi.org/10.6069/2MZZ-6B61"}, {"dataset_uid": "200313", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Beta Version of Plume Model", "url": "https://github.com/icepack/plumes"}, {"dataset_uid": "200315", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Pine Island Basin Scale Model", "url": "https://github.com/fastice/icesheetModels"}, {"dataset_uid": "200314", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "icepack", "url": "https://github.com/icepack/icepack"}], "date_created": "Fri, 13 May 2022 00:00:00 GMT", "description": "The West Antarctic Ice Sheet contains enough ice to raise global sea levels by 3-4 meters. Ice-sheet volume falls, and sea level increases, when more ice is lost to the ocean by glacier flow than is replaced by snowfall. Glacier speed is reduced when ice shelves, which are the floating extensions of the ice sheets, are present. Processes that affect ice shelf thickness and extent therefore influence the rates of grounded ice loss and sea-level rise. West Antarctica is currently losing ice, at an accelerating rate, with most loss occurring in the Amundsen Sea region via discharge from Pine Island and Thwaites glaciers. This loss was initiated by increased circulation of relatively warm ocean water beneath these glacier\u0027s ice shelves, causing them to thin by melting. However, this melting also depends on how the changing shape of the ice shelves affects the ocean circulation beneath them and the speeds of the grounded glaciers upstream. Limited understanding of these processes leads to uncertainties in estimates of future ice loss. This interdisciplinary project brings together glaciologists and oceanographers from three US institutions to study the interactions between changing glacier flow, ice shelf shape and extent, and ocean circulation. Data and numerical models will be used to identify the key processes that determine how rapidly this region can shed ice. The project team will train postdocs and graduate students in cutting-edge modeling techniques, and educate the public about Antarctic ice loss through talks, school science fairs, and Seattle Science Center\u0027s annual Polar Science Weekend. The project team will conduct simulations, using a combination of ice-sheet and ocean models, to reduce uncertainties in projected ice loss from Pine Island and Thwaites glaciers by: (i) assessing how ice-shelf melt rates will change as the ice-shelf cavities evolve through melting and grounding-line retreat, and (ii) improving understanding of the sensitivity of sub-shelf melt rates to changes in ocean state on the nearby continental shelf. These studies will reduce uncertainty on ice loss and sea-level rise estimates, and lay the groundwork for development of future fully-coupled ice-sheet/ocean models. The project will first develop high-resolution ice-shelf-cavity circulation models driven by modern observed regional ocean state and validated with estimates of melt derived from satellite observations. Next, an ice-flow model will be used to estimate the future grounding retreat. An iterative process with the ocean-circulation and ice-flow models will then simulate melt rates at each stage of retreat. These results will help assess the validity of the hypothesis that unstable collapse of the Amundsen Sea sector of West Antarctica is underway, which was based on simplified models of melt rate. These models will also provide a better understanding of the sensitivity of melt to regional forcing such as changes in Circumpolar Deep Water temperature and wind-driven changes in thermocline height. Finally, several semi-coupled ice-ocean simulations will help determine the influence of the ocean-circulation driven melt over the next several decades. These simulations will provide a much-improved understanding of the linkages between far-field ocean forcing, cavity circulation and melting, and ice-sheet response.", "east": -86.0, "geometry": "POINT(-95 -77)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIER MOTION/ICE SHEET MOTION; USA/NSF; ICE SHEETS; AMD; USAP-DC; MODELS; Amd/Us; Pine Island Glacier", "locations": "Pine Island Glacier", "north": -73.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Joughin, Ian; Dutrieux, Pierre; Padman, Laurence; Springer, Scott", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "Uni. Washington ResearchWorks Archive", "repositories": "GitHub; Uni. Washington ResearchWorks Archive", "science_programs": null, "south": -81.0, "title": "Collaborative Research: Modeling ice-ocean interaction for the rapidly evolving ice shelf cavities of Pine Island and Thwaites glaciers, Antarctica ", "uid": "p0010318", "west": -104.0}, {"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": "Trajectories for APEX floats 9223 and 9224 from acoustic tracking using artoa4argo, Mar 2022-Feb 2023; 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"}, {"dataset_uid": "601852", "doi": "10.15784/601852", "keywords": "Antarctica; Continental Slope; Cryosphere; Eddy; Float Trajectory; HAFOS; Weddell Sea", "people": "Boebel, Olaf; Hancock, Cathrine", "repository": "USAP-DC", "science_program": null, "title": "Trajectories for APEX floats 9223 and 9224 from acoustic tracking using artoa4argo, Mar 2022-Feb 2023", "url": "https://www.usap-dc.org/view/dataset/601852"}], "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. 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 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": 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": "2122248 Waters, Laura", "bounds_geometry": "POLYGON((-127.143608 -77.1380528,-127.1012394 -77.1380528,-127.0588708 -77.1380528,-127.0165022 -77.1380528,-126.9741336 -77.1380528,-126.931765 -77.1380528,-126.8893964 -77.1380528,-126.8470278 -77.1380528,-126.8046592 -77.1380528,-126.7622906 -77.1380528,-126.719922 -77.1380528,-126.719922 -77.14809141,-126.719922 -77.15813002,-126.719922 -77.16816863,-126.719922 -77.17820724,-126.719922 -77.18824585,-126.719922 -77.19828446,-126.719922 -77.20832307,-126.719922 -77.21836168,-126.719922 -77.22840029,-126.719922 -77.2384389,-126.7622906 -77.2384389,-126.8046592 -77.2384389,-126.8470278 -77.2384389,-126.8893964 -77.2384389,-126.931765 -77.2384389,-126.9741336 -77.2384389,-127.0165022 -77.2384389,-127.0588708 -77.2384389,-127.1012394 -77.2384389,-127.143608 -77.2384389,-127.143608 -77.22840029,-127.143608 -77.21836168,-127.143608 -77.20832307,-127.143608 -77.19828446,-127.143608 -77.18824585,-127.143608 -77.17820724,-127.143608 -77.16816863,-127.143608 -77.15813002,-127.143608 -77.14809141,-127.143608 -77.1380528))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 19 Aug 2021 00:00:00 GMT", "description": "This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). The geologic record reveals that volcanic activity increases when glaciers retreat and major ice sheets thin. This relationship produces a positive feedback mechanism where the uptick in volcanism increases greenhouse gasses concentrations, leading to climate warming and further deglaciation. Although the pattern between volcanism and deglaciation is observed in the geologic record, the exact mechanism(s) by which glaciers impact a volcanic plumbing system is unknown. This project focuses on Mount Waesche, a volcano in West Antarctica, that frequently erupts during warm, interglacial periods and undergoes a period of less activity during cold, glacial periods. This project will examine compositions of the rocks and minerals from Mount Waesche to determine magma storage depths, allowing the investigators to understand how magma plumbing systems change in response to glacial cycles. These results will be compared with geodynamic simulations to understand the physics behind the effects of deglaciation on the magmatic plumbing systems within Earth\u2019s crust. The investigators will additionally partner with Mentoring Kids Works to develop several Polar and Earth Science Educational Modules aimed at improving reading skills in third grade students in New Mexico. The proposed Polar and Earth Science program consists of modules that include readings of books introducing students to Earth and Polar science themes, paired with Earth and Polar Science activities, followed by simple experiments, where students make predictions and collect data. Information required to implement our Polar and Earth Science curriculum will be made available online. Isotopic and sedimentary datasets reveal that volcanic activity typically increases during interglacial periods. However, the physical mechanisms through which changes in the surface loading affect volcanic magmatic plumbing systems remain unconstrained. Recently generated 40Ar/39Ar eruption ages indicate that 86% of the dated samples from Mt. Waesche, a late Quaternary volcano in Marie Byrd land, correlate with interglacial periods, suggesting this volcano uniquely responds to changes in the West Antarctic Ice Sheet. We propose to combine the petrology of Mount Waesche\u2019s volcanic record, constraints on changing ice loads through time, and geodynamic modelling to: (1) Determine how pre-eruptive storage conditions change during glacial and interglacial periods using whole rock and mineral compositions of volcanic rocks; (2) Conduct geodynamic modeling to elucidate the relationship between lithospheric structure, temporal variations in ice sheet thickness, and subsequent changes in crustal stresses and magmatic transport and, therefore, the mechanism(s) by which deglaciation impacts magmatic plumbing systems; (3) Use the outcomes of objectives (1) and (2) to provide new constraints on the changes in ice sheet thickness through time that could plausibly trigger future volcanic and magmatic activity in West Antarctica. This collaborative approach will provide a novel methodology to determine prior magnitudes and rates of ice load changes within the Marie Byrd Land region of Antarctica. Lastly, estimates of WAIS elevation changes from this study will be compared to ongoing studies at Mount Waesche focused on constraining last interglacial ice sheet draw down using cosmogenic exposure ages obtained from shallow drilling. The scope of work also includes a partnership with Mentoring Kids Works to develop several Polar and Earth Science Educational Modules aimed at improving reading skills in third grade students in New Mexico. The proposed Polar and Earth Science program consists of modules that include readings of books introducing students to Earth and Polar science themes, paired with Earth and Polar Science activities, followed by simple experiments, where students make predictions and collect data. Information required to implement our Polar and Earth Science curriculum will be made available online. 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": -126.719922, "geometry": "POINT(-126.931765 -77.18824585)", "instruments": null, "is_usap_dc": true, "keywords": "Mt. Waesche; GEOCHEMISTRY; LITHOSPHERIC PLATE MOTION; STRESS; Amd/Us; West Antarctica; Executive Committee Range; NOT APPLICABLE; USAP-DC; AMD; MAJOR ELEMENTS; USA/NSF; ROCKS/MINERALS/CRYSTALS", "locations": "West Antarctica; Mt. Waesche; Executive Committee Range", "north": -77.1380528, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Waters, Laura; Naliboff, John; Zimmerer, Matthew", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repositories": null, "science_programs": null, "south": -77.2384389, "title": "Integrating petrologic records and geodynamics: Quantifying the effects of glaciation on crustal stress and eruptive patterns at Mt. Waesche, Executive Committee Range, Antarctica", "uid": "p0010248", "west": -127.143608}, {"awards": "1947040 Postlethwait, John", "bounds_geometry": "POLYGON((-65.3 -63.3,-65 -63.3,-64.7 -63.3,-64.4 -63.3,-64.1 -63.3,-63.8 -63.3,-63.5 -63.3,-63.2 -63.3,-62.9 -63.3,-62.6 -63.3,-62.3 -63.3,-62.3 -63.47,-62.3 -63.64,-62.3 -63.81,-62.3 -63.98,-62.3 -64.15,-62.3 -64.32,-62.3 -64.49,-62.3 -64.66,-62.3 -64.83,-62.3 -65,-62.6 -65,-62.9 -65,-63.2 -65,-63.5 -65,-63.8 -65,-64.1 -65,-64.4 -65,-64.7 -65,-65 -65,-65.3 -65,-65.3 -64.83,-65.3 -64.66,-65.3 -64.49,-65.3 -64.32,-65.3 -64.15,-65.3 -63.98,-65.3 -63.81,-65.3 -63.64,-65.3 -63.47,-65.3 -63.3))", "dataset_titles": "18 SSU rDNA type sequences for Notoxcellia coronata (nov. sp.); 18 SSU rDNA type sequences for Notoxcellia picta (nov. sp.); Expedition Data of LMG1805; Fish pictures and skin pathology of X-cell infection in Trematomus scotti.; Gonad and skin histology of Trematomus loennbergii infected by Notoxcellia sp.; Histopathology of X-cell xenomas in Trematomus scotti and Nototheniops larseni.; In situ hybridization of X-cell and host fish 18S SSU rRNA in alternate sections of tumor xenomas.; Metagenomic analysis of apparently healthy and tumor samples using Kaiju software ; microMRI analyses of Trematomus scotti Tsco_18_08 with X-cell xenomas; Morphological and pathological data of Trematomus scotti specimens captured on May 30th, 2018 in Andvord Bay.; Morphological, fecundity, and age data of Trematomus scotti from Andvord Bay and the Weddell Sea.; Nomenclatural Act for the genus Notoxcellia; Nomenclatural Act for the species Notoxcellia coronata; Nomenclatural Act for the species Notoxcellia picta; Phylogenetic Analysis of Notoxcellia species.; Phylogenetic Analysis of Notoxcellia species, including novel Ross Sea specimen; Raw Illumina sequencing reads from skin tumors and visually healthy skins from Trematomus scotti and Nototheniops larseni; Similarity matrices of Notoxcellia spp.; Temperature profiles at five fishing locations on the West Antarctic Peninsula during austral fall 2018.; Trematomus scotti mt-co1 sequence alignment.; Trematomus scotti with X-cell xenomas", "datasets": [{"dataset_uid": "601917", "doi": "10.15784/601917", "keywords": "Alveolata; Antarctic; Cryosphere; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Xcellidae", "people": "Devine, Jennifer; Desvignes, Thomas; Postlethwait, John; P\u00e9ron, Clara", "repository": "USAP-DC", "science_program": null, "title": "Similarity matrices of Notoxcellia spp.", "url": "https://www.usap-dc.org/view/dataset/601917"}, {"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": "200443", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of LMG1805", "url": "https://doi.org/10.7284/907930"}, {"dataset_uid": "601892", "doi": "10.15784/601892", "keywords": "Antarctica; Biota; CO1; COX1; Cryonotothenioid; Cryosphere; Genetic Sequences; LMG1805; MT-CO1; Nototheniidae; Notothenioid; Population Genetics", "people": "Schiavon, Luca ; Postlethwait, John; Desvignes, Thomas; Papetti, Chiara", "repository": "USAP-DC", "science_program": null, "title": "Trematomus scotti mt-co1 sequence alignment.", "url": "https://www.usap-dc.org/view/dataset/601892"}, {"dataset_uid": "601893", "doi": "10.15784/601893", "keywords": "Age; Antarctica; Biota; Cryonotothenioid; Cryosphere; Fecundity; Growth; Length; Nototheniidae; Oceans; Otolith; Reproduction; Weight", "people": "Lucassen, Magnus; Streeter, Margaret; Le Francois, Nathalie; Grondin, Jacob; Valdivieso, Alejandro; Sguotti, Camilla; Postlethwait, John; La Mesa, Mario; Detrich, H. William; Mark, Felix C; Riginella, Emilio; Papetti, Chiara; Desvignes, Thomas; Cal\u00ec, Federico", "repository": "USAP-DC", "science_program": null, "title": "Morphological, fecundity, and age data of Trematomus scotti from Andvord Bay and the Weddell Sea.", "url": "https://www.usap-dc.org/view/dataset/601893"}, {"dataset_uid": "200383", "doi": "", "keywords": null, "people": null, "repository": "ZooBank", "science_program": null, "title": "Nomenclatural Act for the species Notoxcellia coronata", "url": "https://zoobank.org/NomenclaturalActs/194d91b2-e268-4238-89e2-385819f2c35b"}, {"dataset_uid": "601539", "doi": "10.15784/601539", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Xcellidae", "people": "Postlethwait, John; Desvignes, Thomas", "repository": "USAP-DC", "science_program": null, "title": "In situ hybridization of X-cell and host fish 18S SSU rRNA in alternate sections of tumor xenomas.", "url": "https://www.usap-dc.org/view/dataset/601539"}, {"dataset_uid": "601538", "doi": "10.15784/601538", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Xcellidae", "people": "Desvignes, Thomas; Postlethwait, John; Lauridsen, Henrik", "repository": "USAP-DC", "science_program": null, "title": "microMRI analyses of Trematomus scotti Tsco_18_08 with X-cell xenomas", "url": "https://www.usap-dc.org/view/dataset/601538"}, {"dataset_uid": "601537", "doi": "10.15784/601537", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Xcellidae", "people": "Desvignes, Thomas; Postlethwait, John; Varsani, Arvind; Kraberger, Simona ; Fontenele, Rafaela S. ", "repository": "USAP-DC", "science_program": null, "title": "Metagenomic analysis of apparently healthy and tumor samples using Kaiju software ", "url": "https://www.usap-dc.org/view/dataset/601537"}, {"dataset_uid": "601536", "doi": "10.15784/601536", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Xcellidae", "people": "Desvignes, Thomas; Postlethwait, John; Murray, Katrina N. ; Kent, Michael L. ", "repository": "USAP-DC", "science_program": null, "title": "Histopathology of X-cell xenomas in Trematomus scotti and Nototheniops larseni.", "url": "https://www.usap-dc.org/view/dataset/601536"}, {"dataset_uid": "601915", "doi": "10.15784/601915", "keywords": "Alveolata; Antarctic; Cryosphere; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Xcellidae", "people": "Postlethwait, John; Desvignes, Thomas; P\u00e9ron, Clara; Devine, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Phylogenetic Analysis of Notoxcellia species, including novel Ross Sea specimen", "url": "https://www.usap-dc.org/view/dataset/601915"}, {"dataset_uid": "601916", "doi": "10.15784/601916", "keywords": "Alveolata; Antarctica; Cryosphere; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Ross Sea; Xcellidae", "people": "Postlethwait, John; Desvignes, Thomas; P\u00e9ron, Clara; Devine, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Gonad and skin histology of Trematomus loennbergii infected by Notoxcellia sp.", "url": "https://www.usap-dc.org/view/dataset/601916"}, {"dataset_uid": "601501", "doi": "10.15784/601501", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Biota; Notoxcellia Coronata; Notoxcellia Picta; Oceans; Perkinsozoa; Xcellidae", "people": "Postlethwait, John; Desvignes, Thomas; Varsani, Arvind", "repository": "USAP-DC", "science_program": null, "title": "Phylogenetic Analysis of Notoxcellia species.", "url": "https://www.usap-dc.org/view/dataset/601501"}, {"dataset_uid": "601496", "doi": "10.15784/601496", "keywords": "Andvord Bay; Antarctica; Fish", "people": "Desvignes, Thomas; Postlethwait, John; Lauridsen, Henrik", "repository": "USAP-DC", "science_program": null, "title": "Fish pictures and skin pathology of X-cell infection in Trematomus scotti.", "url": "https://www.usap-dc.org/view/dataset/601496"}, {"dataset_uid": "601495", "doi": "10.15784/601495", "keywords": "Antarctica; Antarctic Peninsula", "people": "Desvignes, Thomas", "repository": "USAP-DC", "science_program": null, "title": "Temperature profiles at five fishing locations on the West Antarctic Peninsula during austral fall 2018.", "url": "https://www.usap-dc.org/view/dataset/601495"}, {"dataset_uid": "601494", "doi": "10.15784/601494", "keywords": "Andvord Bay; Antarctica; Fish", "people": "Postlethwait, John; Le Francois, Nathalie; Desvignes, Thomas; Lauridsen, Henrik", "repository": "USAP-DC", "science_program": null, "title": "Morphological and pathological data of Trematomus scotti specimens captured on May 30th, 2018 in Andvord Bay.", "url": "https://www.usap-dc.org/view/dataset/601494"}, {"dataset_uid": "200262", "doi": "", "keywords": null, "people": null, "repository": "MorphoSource", "science_program": null, "title": "Trematomus scotti with X-cell xenomas", "url": "https://www.morphosource.org/projects/000405843?locale=en"}, {"dataset_uid": "200275", "doi": "", "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "18 SSU rDNA type sequences for Notoxcellia coronata (nov. sp.)", "url": "https://www.ncbi.nlm.nih.gov/nuccore/OL630144"}, {"dataset_uid": "200276", "doi": "", "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "18 SSU rDNA type sequences for Notoxcellia picta (nov. sp.)", "url": "https://www.ncbi.nlm.nih.gov/nuccore/OL630145"}, {"dataset_uid": "200277", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "Raw Illumina sequencing reads from skin tumors and visually healthy skins from Trematomus scotti and Nototheniops larseni", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA789574"}, {"dataset_uid": "200382", "doi": "", "keywords": null, "people": null, "repository": "ZooBank", "science_program": null, "title": "Nomenclatural Act for the genus Notoxcellia", "url": "https://zoobank.org/NomenclaturalActs/5cf9609e-0111-4386-8518-bd50b5bdde0e"}, {"dataset_uid": "200384", "doi": "", "keywords": null, "people": null, "repository": "ZooBank", "science_program": null, "title": "Nomenclatural Act for the species Notoxcellia picta", "url": "https://zoobank.org/NomenclaturalActs/31062dd2-7202-47fa-86e0-7be5c55ac0e2"}], "date_created": "Thu, 01 Jul 2021 00:00:00 GMT", "description": "Antarctica\u2019s native animals face increasing stressors from warming oceans. A key unanswered question is how Antarctic life will respond. If warmer waters contribute to fish disease susceptibility, then iconic Antarctic predators they support, including penguins, seals, and killer whales, will suffer. A recent scientific cruise on the Antarctic peninsula encountered a population of crowned notothen fish that were plagued by pink, wart-like tumors that covered 10% to 30% of the body surface on about a third of the animals. Similar tumors had not previously been reported, suggesting that this might be a new disease that threatens Antarctic fish. The goal of proposed work is to identify the biological origins of the tumor and how it affects cell function and organismal physiology. The work is potentially transformative because it studies what might be a harbinger of Antarctic fish responses to global climate change. The project has several Broader Impacts. First, it will publicize the tumors. Because Antarctic researchers have never reported a tumor epidemic, the community must become aware of the outbreak and the tumor\u2019s distinct diagnostic features. Second, dissemination of project results will stir further research to determine if this is an isolated event or is becoming a general phenomenon, and thus a broad concern for Antarctic ecosystems. Third, assays the project develops to detect the disease will enhance research infrastructure. Finally, work will broaden the nation\u2019s scientific workforce by providing authentic research experiences for high school students and undergraduates from groups underrepresented in scientific research. The overall goal of proposed work is to identify the biological origins of the neoplasia and how it affects cell function and physiology. Aim 1 is to identify the pathogenic agent. Aim 1a is to test the hypothesis that a virus causes the neoplasia by isolating and sequencing viral nucleic acids from neoplasias and from animals that are not visibly affected. Aim 1b is to test neoplasias for bacteria, fungi, protozoa, or invertebrate parasites not present in healthy skin. Aim 2 is to learn how the disease alters the biology of affected cells. Aim 2a is to examine histological sections of affected and control tissues to see if the neoplasias are similar to previously reported skin diseases in temperate water fishes. Aim 2b is to examine the function of neoplastic cells by RNA-seq transcriptomics to identify genes that are differentially expressed in neoplasias and normal skin. Achieving these Aims will advance knowledge by identifying the causes and consequences of an outbreak of neoplasias in Antarctic fish. Proposed work is significant because it is the first to investigate a neoplasia cluster in Antarctic fish. 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": -62.3, "geometry": "POINT(-63.8 -64.15)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; Andvord Bay; Amd/Us; PROTISTS; BENTHIC; FISH; Dallmann Bay; USAP-DC; NSF/USA; AMD", "locations": "Andvord Bay; Dallmann Bay", "north": -63.3, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Postlethwait, John; Varsani, Arvind; Desvignes, Thomas", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "GenBank; MorphoSource; NCBI SRA; R2R; USAP-DC; ZooBank", "science_programs": null, "south": -65.0, "title": "EAGER: Origin and Physiological Consequences of a Neoplasm Outbreak in Antarctic Fish ", "uid": "p0010221", "west": -65.3}, {"awards": "1341376 Tabor, Neil; 1341475 Smith, Nathan; 2001033 Makovicky, Peter; 1341304 Sidor, Christian; 1341645 Makovicky, Peter", "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": "Around 252 million years ago, a major mass extinction wiped out upwards of 90% of species on Earth. Coincident with this extinction, the Antarctic portion of the supercontinent of Pangea transitioned to a warmer climatic regime and became devoid of glaciers. Little is known about the survivors of the extinction in Antarctica, although it has been hypothesized that the continent\u0027s high latitude location shielded it from the worst of the extinction\u0027s effects. The Shackleton Glacier region is the best place to study this extinction in Antarctica because it exposes an abundance of correct age rocks and relevant fossils were found there in the 1960s and 1980s. For this research, paleontologists will study fossil vertebrates that span from about 260 to 240 million years ago to understand how life evolved at high latitudes in the face of massive climate change. In addition, geologists will use fossil soils and fossil plant matter to more precisely reconstruct the climate of Antarctica across this extinction boundary. These data will allow for a more complete understanding of ancient climates and how Antarctic life compared to that at lower latitudes. Undergraduate and graduate students will be actively involved in this research. Public engagement in Antarctic science will be accomplished at several natural history museums. This three-year project will examine the evolution of Permo-Triassic paleoenvironments and their vertebrate communities by conducting fieldwork in the Shackleton Glacier region of Antarctica. The team will characterize the Permo-Triassic boundary within Shackleton area strata and correlate it to other stratigraphic successions in the region (e.g. via stable carbon isotope stratigraphy of fossilized plant organic matter). The researchers will use multiple types of data to assess the 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 (~70\u00b0 S) tetrapod fauna of the entire Triassic and thus has the potential to shed important light on the evolution of polar life during the early Mesozoic. The biology of Triassic vertebrates from Antarctica will be compared to conspecifics from lower paleolatitudes through analysis of growth in bone and tusk histology. An interdisciplinary approach will be used 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.", "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": "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. 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.", "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": "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. 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 \u003e50% 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.", "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": "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. 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.", "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": "1541285 Tauxe, Lisa", "bounds_geometry": "POLYGON((162.144 -77.2233,162.8676 -77.2233,163.5912 -77.2233,164.3148 -77.2233,165.0384 -77.2233,165.762 -77.2233,166.4856 -77.2233,167.2092 -77.2233,167.9328 -77.2233,168.6564 -77.2233,169.38 -77.2233,169.38 -77.34097,169.38 -77.45864,169.38 -77.57631,169.38 -77.69398,169.38 -77.81165,169.38 -77.92932,169.38 -78.04699,169.38 -78.16466,169.38 -78.28233,169.38 -78.4,168.6564 -78.4,167.9328 -78.4,167.2092 -78.4,166.4856 -78.4,165.762 -78.4,165.0384 -78.4,164.3148 -78.4,163.5912 -78.4,162.8676 -78.4,162.144 -78.4,162.144 -78.28233,162.144 -78.16466,162.144 -78.04699,162.144 -77.92932,162.144 -77.81165,162.144 -77.69398,162.144 -77.57631,162.144 -77.45864,162.144 -77.34097,162.144 -77.2233))", "dataset_titles": "Four-Dimensional paleomagnetic dataset: Late Neogene paleodirection and paleointensity results from the Erebus Volcanic Province, Antarctica", "datasets": [{"dataset_uid": "200162", "doi": "", "keywords": null, "people": null, "repository": "Magnetics Infomation Consortiums MagIC", "science_program": null, "title": "Four-Dimensional paleomagnetic dataset: Late Neogene paleodirection and paleointensity results from the Erebus Volcanic Province, Antarctica", "url": "https://www2.earthref.org/MagIC/16912/14b%20cd18-4c33-858e-de5eab74c528"}], "date_created": "Mon, 24 Aug 2020 00:00:00 GMT", "description": "The geomagnetic field is decreasing rapidly, leading some to propose that it will undergo collapse followed by a return to its usual strength but in the opposite direction, a phenomenon known as a \"polarity reversal\" which happened last approximately 800,000 years ago. Such a collapse would have a potentially devastating effect on the ability of the magnetic field to shield us from cosmic ray bombardment, placing our electrical grid at grave risk, among other things. The probability of such a drastic event happening depends on the average strength of the magnetic field. If the average is approximately equal to the present field (as many researchers assume), then the fact that the field is dropping rapidly would be more alarming than if the magnetic field is quite a bit higher than average, as implied by the current data for the ancient magnetic field from Antarctica. The argument over the average field strength stems from the difficulty of its estimation. The new approach advocated for in this proposal will allow researchers to obtain a robust data set for high southerly latitudes which will greatly enhance confidence in estimates of the average ancient field strength, contributing to our ability to assess the likelihood of catastrophic collapse of the geomagnetic field. The difficulty in estimating the average magnetic field strength over the past five million years is apparent when one examines data for ancient field strength as a function of latitude. Directions of the geomagnetic field have been well approximated by an axial dipole (bar magnetic) at the center of the Earth that is aligned with the spin axis. But the signal of such an axial geomagnetic dipole, whereby the field strength doubles from the equator to the poles, is not readily apparent in the database of field strength estimates from the last five million years. There are several possible explanations for this troubling failure: 1) combining data from different ages with possibly different average intensities leads to an inappropriate comparison of field states, 2) there is a depression of field strength at high latitude, perhaps reflecting the role of the `tangent cylinder?, or 3) there is noise and/or bias introduced by poor selection criteria or poor experimental design. The latter is a likely explanation as published data from the 1960 lava flow on Hawaii display the entire range of intensity values observed on the Earth\u0027s surface today, yet samples from this lava flow should all have one distinct value. This proposal benefits from the development of new experimental methods, better field strategies and a new approach to data selection that will allow accurate estimation of the ancient field strength through a comprehensive field campaign to collect lava flow samples from previously studied outcrops targeting the most promising material. These will be analyzed using the most robust experimental protocol and subjected to rigorous selection criteria proven to reject inaccurate results, leading to both accurate and precise estimates of ancient field strength.", "east": 169.38, "geometry": "POINT(165.762 -77.81165)", "instruments": null, "is_usap_dc": true, "keywords": "McMurdo; PALEOMAGNETISM; LABORATORY", "locations": "McMurdo", "north": -77.2233, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Tauxe, Lisa; Staudigel, Hubertus", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "Magnetics Infomation Consortiums MagIC", "repositories": "Magnetics Infomation Consortiums MagIC", "science_programs": null, "south": -78.4, "title": "Finding the Missing Geomagnetic Dipole Signal in Global Pleointensity Data: Revisiting the High Southerly Latitudes", "uid": "p0010122", "west": 162.144}, {"awards": "1543450 Countway, Peter", "bounds_geometry": "POLYGON((-66 -63,-65.7 -63,-65.4 -63,-65.1 -63,-64.8 -63,-64.5 -63,-64.2 -63,-63.9 -63,-63.6 -63,-63.3 -63,-63 -63,-63 -63.3,-63 -63.6,-63 -63.9,-63 -64.2,-63 -64.5,-63 -64.8,-63 -65.1,-63 -65.4,-63 -65.7,-63 -66,-63.3 -66,-63.6 -66,-63.9 -66,-64.2 -66,-64.5 -66,-64.8 -66,-65.1 -66,-65.4 -66,-65.7 -66,-66 -66,-66 -65.7,-66 -65.4,-66 -65.1,-66 -64.8,-66 -64.5,-66 -64.2,-66 -63.9,-66 -63.6,-66 -63.3,-66 -63))", "dataset_titles": "Biogenic Sulfur Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Dissolved Inorganic Nutrient Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments ; Dissolved Organic Carbon (DOC) and Total Dissolved Nitrogen (TDN) Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Flow Cytometry Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Heterotrophic Bacterial Production Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Western Antarctic Peninsula plankton raw sequence reads", "datasets": [{"dataset_uid": "200337", "doi": "", "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Western Antarctic Peninsula plankton raw sequence reads", "url": "https://dataview.ncbi.nlm.nih.gov/object/PRJNA870587?reviewer=bmud2tbbrqbus79i2n2hb83uio"}, {"dataset_uid": "601645", "doi": "10.15784/601645", "keywords": "Antarctica; Nitrate; Nitrite; Palmer Station; Phosphate", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Dissolved Inorganic Nutrient Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments ", "url": "https://www.usap-dc.org/view/dataset/601645"}, {"dataset_uid": "601647", "doi": "10.15784/601647", "keywords": "Antarctica; Palmer Station; Phytoplankton", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Flow Cytometry Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601647"}, {"dataset_uid": "601646", "doi": "10.15784/601646", "keywords": "Antarctica; Carbon; Dissolved Organic Carbon; Nitrogen; Palmer Station; TDN; Total Dissolved Nitrogen", "people": "Matrai, Patricia; Countway, Peter", "repository": "USAP-DC", "science_program": null, "title": "Dissolved Organic Carbon (DOC) and Total Dissolved Nitrogen (TDN) Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601646"}, {"dataset_uid": "601648", "doi": "10.15784/601648", "keywords": "Antarctica; Biota; Dimethyl Sulfide; Dimethylsulfoniopropionate; Dimethylsulfoxide; DMSP; DMSP Lyase; Palmer Station", "people": "Matrai, Patricia; Countway, Peter", "repository": "USAP-DC", "science_program": null, "title": "Biogenic Sulfur Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601648"}, {"dataset_uid": "601644", "doi": "10.15784/601644", "keywords": "3H-Leu; Antarctica; Bacteria; Biota; DMSP; Heterotrophic Bacterial Production; Palmer Station", "people": "Matrai, Patricia; Countway, Peter", "repository": "USAP-DC", "science_program": null, "title": "Heterotrophic Bacterial Production Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601644"}], "date_created": "Sat, 01 Aug 2020 00:00:00 GMT", "description": "The Southern Ocean in the vicinity of Antarctica is a region characterized by seasonally-driven marine phytoplankton blooms that are often dominated by microalgal species which produce large amounts of dimethylsulfoniopropionate (DMSP). DMSP can be converted to the compound dimethylsulfide (DMS) which is a molecule that can escape into the atmosphere where it is known to have strong condensation properties that are involved in regional cloud formation. Production of DMSP can influence the diversity and composition of microbial assemblages in seawater and the types and activities of microbes in the seawater will likely affect the magnitude of DMSP\\DMS production. The proposal aims to examine the role of DMSP in structuring the microbial communities in Antarctic waters and how this structuring may influence DMSP cycling. The project will leverage the Antarctic research to introduce concepts and data linking microbial diversity and biogeochemistry to a range of audiences (including high school and undergraduate students in Maine). The project will also engage teacher and students in rural K-8 schools and will allow a collaboration with a science writer and illustrator who will join the team in the field. The writer will use the southern ocean experience as the setting for a poster and a book about the proposed research and the scientists studying extreme environments. The project will examine (1) the extent to which the cycling of DMSP in southern ocean waters influences the composition and diversity of bacterial and protistan assemblages; (2) conversely, whether the composition and diversity of southern ocean protistan and bacterial assemblages influence the magnitude and rates of DMSP cycling; (3) the expression of DMSP degradation genes by marine bacteria seasonally and in response to additions of DMSP; and, to synthesize these results by quantifying (4) the microbial networks resulting from the presence of DMSP-producers and DMSP-consumers along with their predators, all involved in the cycling of DMSP in southern ocean waters. The work will be accomplished by conducting continuous growth experiments with DMSP-amended natural samples during field sampling of different microbial communities present in summer and fall. Data from the molecular (such as 16S/ 18S tag sequences, DMSP-cycle gene transcripts) and biogeochemical (such as biogenic sulfur cycling, bacterial production, microbial biomass) investigations will be integrated via network analysis.", "east": -63.0, "geometry": "POINT(-64.5 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; COMMUNITY DYNAMICS; FIELD INVESTIGATION; AMD; PLANKTON; Amd/Us; BIOGEOCHEMICAL CYCLES; Palmer Station; USA/NSF", "locations": "Palmer Station", "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Countway, Peter", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "GenBank", "repositories": "GenBank; USAP-DC", "science_programs": null, "south": -66.0, "title": "Microbial Community Structure and Expression of Functional Genes Involved in the Seasonal Cycling of DMSP in the Southern Ocean", "uid": "p0010120", "west": -66.0}, {"awards": "1543328 Van Mooy, Benjamin", "bounds_geometry": null, "dataset_titles": "Lipidomics of Antarctic waters. (TBD)", "datasets": [{"dataset_uid": "200149", "doi": "TBD", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Lipidomics of Antarctic waters. (TBD)", "url": "https://www.bco-dmo.org/data"}], "date_created": "Fri, 19 Jun 2020 00:00:00 GMT", "description": "The depletion of stratospheric ozone over Antarctica leads to abnormally high levels of ultraviolet radiation (UVR) from the sun reaching the surface of the ocean. This phenomenon is predicted to continue for the next half century, despite bans on ozone-destroying pollutants. Phytoplankton in the near surface ocean are subjected to variable amounts of UVR and contain a lot of lipids (fats). Because phytoplankton are at the base of the food chain their lipids makes their way into the Antarctic marine ecosystem\u0027s food web. The molecular structures of phytoplankton lipids are easily altered by UVR. When this happens, their lipids can be transformed from healthy molecules into potentially harmful molecules(oxylipins) known to be disruptive to reproductive and developmental processes. This project will use state-of-the-art molecular methods to answer questions about extent to which UVR damages lipid molecules in phytoplankton, and how these resultant molecules might effect the food chain in the ocean near Antarctica. Lipid peroxidation is often invoked as consequence of increased exposure of phytoplankton to UVR-produced reactive oxygen species (ROS), but the literature is practically silent on peroxidized lipids and their byproducts (i.e. oxylipins) in the ocean. In waters of the West Antarctic Peninsula (WAP), spring-time blooms of diatoms contribute significantly to overall marine primary production. Oxylipins from diatoms can be highly bioactive; their impact on zooplankton grazers, bacteria, and other phytoplankton has been the subject of intense study. However, almost all of this work has focused on the production of oxylipins via enzymatic pathways, not by pathways involving UVR and/or ROS. Furthermore, rigorous experimental work on the effects of oxylipins has been confined almost exclusively to pure cultures and artificial communities. Thus, the true potential of these molecules to disrupt carbon cycling is very poorly-constrained, and is entirely unknown in the waters of the WAP. Armed with new highly-sensitive, state-of-the-art analytical techniques based on high-mass-resolution mass spectrometry, the principal investigator and his research group have begun to uncover an exquisite diversity of oxylipins in natural WAP planktonic communities. These techniques will be applied to understand the connections between UVR, ROS, oxylipins, and carbon cycling. The project will answer the question of how UVR, via ROS, affects oxylipin production by diatoms in WAP surface waters in controlled experiments conducted at a field station. With the answer to this question in hand, the project will also seek to answer how this phenomenon impacts the flow of carbon, particularly the export of organic carbon from the system, during a research cruise. The level of UVR-induced stresses experienced by oxylipin-rich planktonic communities in the WAP is unique, making Antarctica the only location for answering these fundamental questions. Major activities will include laboratory experiments with artificial membranes and diatom cultures, as well field experiments with phytoplankton, zooplankton, and bacteria in WAP waters.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Oxylipins; Palmer Station; UV Radiation; USAP-DC; West Antarctic Shelf; NOT APPLICABLE; AQUATIC SCIENCES; Phytoplankton", "locations": "West Antarctic Shelf; Palmer Station", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Van Mooy, Benjamin", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": null, "title": "Production and Fate of Oxylipins in Waters of the Western Antarctic Peninsula: Linkages Between UV Radiation, Lipid Peroxidation, and Carbon Cycling", "uid": "p0010109", "west": null}, {"awards": "1744570 Galloway, Aaron; 1744550 Amsler, Charles; 1744584 Klein, Andrew; 1744602 Iken, Katrin", "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; Chemical composition data for Desmarestia menziesii; Chemical composition data for Himantothallus grandifolius; Chemical composition data for Iridaea ; Chemical composition data for Sarcopeltis antarctica ; 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": "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": "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": "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": "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": "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": "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": "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": "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": "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": "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": "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"}, {"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": "601882", "doi": "10.15784/601882", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Macroalgae", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Chemical composition data for Desmarestia menziesii", "url": "https://www.usap-dc.org/view/dataset/601882"}, {"dataset_uid": "601883", "doi": "10.15784/601883", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Macroalgae", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Chemical composition data for Himantothallus grandifolius", "url": "https://www.usap-dc.org/view/dataset/601883"}, {"dataset_uid": "601884", "doi": "10.15784/601884", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Macroalgae", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Chemical composition data for Iridaea ", "url": "https://www.usap-dc.org/view/dataset/601884"}, {"dataset_uid": "601885", "doi": "10.15784/601885", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Macroalgae", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Chemical composition data for Sarcopeltis antarctica ", "url": "https://www.usap-dc.org/view/dataset/601885"}], "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. 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. 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": -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": "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; Expedition Data of NBP2202; NBP1902 Expedition data; Physical and geochemical data from sediment cores collected offshore Thwaites Glacier", "datasets": [{"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": "200311", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP2202", "url": "https://www.rvdata.us/search/cruise/NBP2202"}, {"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"}, {"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"}], "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. 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. 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": -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 Earth Sciences; Antarctic Glaciology", "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": "UK PDC", "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": "1341385 Lee, Richard; 1341393 Denlinger, David", "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": "Alaskozetes antarcticus Raw sequence reads; Belgica antarctica Integrated Genome and Transcriptome Project; Data from: Rapid cold hardening protects against sublethal freezing injury in an Antarctic insect", "datasets": [{"dataset_uid": "200053", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Belgica antarctica Integrated Genome and Transcriptome Project", "url": "https://www.ncbi.nlm.nih.gov/bioproject/175916"}, {"dataset_uid": "200054", "doi": " https://doi.org/10.5061/dryad.29p7ng2", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Data from: Rapid cold hardening protects against sublethal freezing injury in an Antarctic insect", "url": "https://datadryad.org/resource/doi:10.5061/dryad.29p7ng2"}, {"dataset_uid": "200052", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Alaskozetes antarcticus Raw sequence reads", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA428758"}], "date_created": "Mon, 12 Aug 2019 00:00:00 GMT", "description": "Polar regions are deserts that are not only cold but also lack access to free water. Antarctic insects have unique survival mechanisms including the ability to tolerate freezing and extensive dehydration, surviving the loss of 70% of their body water. How this is done is of interest not only for understanding seasonal adaptations of insects and how they respond to climate change, but the molecular and physiological mechanisms employed may offer valuable insights into more general mechanisms that might be exploited for cryopreservation and long-term storage of human tissues and organs for transplantation and other medical applications. The investigators will study the proteins that are responsible for removing water from the body, cell level consequences of this, and how the responsible genes vary between populations. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. Each year a K-12 teacher will be a member of the field team and assist with fieldwork and outreach to school children and their teachers. Educational outreach efforts include presentations at local schools and national teacher meetings, providing lesson plans and podcasts on a website, and continuing to publish articles related to this research in education journals. In addition, undergraduate and graduate students will receive extensive training in all aspects of the research project with extended experiences that include publication of scientific papers and presentations at national meetings. This project focuses on deciphering the physiological and molecular mechanisms that enable the Antarctic midge Belgica antarctica to survive environmental stress and the loss of most of its body water in the desiccating polar environment. This extremophile is an ideal system for investigating mechanisms of stress tolerance and local geographic adaptations and its genome has recently been sequenced. This project has three focal areas: 1) Evaluating the role of aquaporins (water channel proteins) in the rapid removal of water from the body by studying expression of their genes during dehydration; 2) Investigating the mechanism of metabolic depression and the role of autophagy (controlled breakdown of cellular components) as a mediator of stress tolerance by studying expression of the genes responsible for autophagy during the dehydration process; and 3) Evaluating the population structure, gene flow, and adaptive variation in physiological traits associated with stress tolerance using a genetic approach that takes advantage of the genomic sequence available for this species coupled with physiological and environmental data from the sampled populations and their habitats.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Antarctica; USAP-DC; ARTHROPODS; NOT APPLICABLE", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Denlinger, David; Lee, Richard", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "NCBI GenBank", "repositories": "Dryad; NCBI GenBank", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Winter Survival Mechanisms and Adaptive Genetic Variation in an Antarctic Insect", "uid": "p0010048", "west": -180.0}, {"awards": "1643735 Li, Yun; 1643901 Zhang, Weifeng; 2021245 Li, Yun", "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": "Dynamic fine-scale sea-icescape shapes adult emperor penguin foraging habitat in East Antarctica; Monthly Stratification Climatology (1978-2021) in Antarctic Coastal Polynyas", "datasets": [{"dataset_uid": "601209", "doi": "10.15784/601209", "keywords": "Animal Behavior Observation; Antarctica; Biota; East Antarctica; GPS; Oceans; Penguin; Southern Ocean", "people": "Pinaud, David; Wienecke, Barbara; Kirkwood, Roger; Ropert-Coudert, Yan; Resinger, Ryan; Jonsen, Ian; Porter-Smith, Rick; Barbraud, Christophe; Ji, Rubao; Jenouvrier, Stephanie; Sumner, Michael; Bost, Charles-Andr\u00e9; Labrousse, Sara; Fraser, Alexander; Tamura, Takeshi", "repository": "USAP-DC", "science_program": null, "title": "Dynamic fine-scale sea-icescape shapes adult emperor penguin foraging habitat in East Antarctica", "url": "https://www.usap-dc.org/view/dataset/601209"}, {"dataset_uid": "601628", "doi": "10.15784/601628", "keywords": "Antarctic; Antarctica; Antarctic Coastal Polynyas; Polynya", "people": "Zhang, Weifeng; Shunk, Nathan; Li, Yun", "repository": "USAP-DC", "science_program": null, "title": "Monthly Stratification Climatology (1978-2021) in Antarctic Coastal Polynyas", "url": "https://www.usap-dc.org/view/dataset/601628"}], "date_created": "Wed, 07 Aug 2019 00:00:00 GMT", "description": "During winter, sea-ice coverage along the Antarctic coast is punctuated by numerous polynyas--isolated openings of tens to hundreds of kilometer wide. These coastal polynyas are hotspots of sea ice production and the primary source regions of the bottom water in the global ocean. They also host high levels of biological activities and are the feeding grounds of Emperor penguins and marine mammals. The polynyas are a key component of the Antarctic coastal system and crucial for the survival of penguins and many other species. These features also differ dramatically from each other in timing of formation, duration, phytoplankton growth season, and overall biological productivity. Yet, the underlying reasons for differences among them are largely unknown. This project studies the fundamental biophysical processes at a variety of polynyas, examines the connection between the physical environment and the phytoplankton and penguin ecology, and investigates the mechanisms behind polynya variability. The results of this interdisciplinary study will provide a context for interpretation of field measurements in Antarctic coastal polynyas, set a baseline for future polynya studies, and examine how polynya ecosystems may respond to local and large-scale environmental changes. The project will include educational and outreach activities that convey scientific messages to a broad audience. It aims to increase public awareness of the interconnection between large-scale environmental change and Antarctic coastal systems. The main objectives of this study are to form a comprehensive understanding of the temporal and spatial variability of Antarctic coastal polynyas and the physical controls of polynya ecosystems. The project takes an interdisciplinary approach and seeks to establish a modeling system centered on the Regional Ocean Modeling System. This system links the ice and ocean conditions to the plankton ecology and penguin population. Applications of the modeling system in representative polynyas, in conjunction with analysis of existing observations, will determine the biophysical influences of individual forcing factors. In particular, this study will test a set of hypothesized effects of winds, offshore water intrusion, ice-shelf melting, sea-ice formation, glacier tongues, and ocean stratification on the timing of polynya phytoplankton bloom and the overall polynya biological productivity. The project will also examine how changing polynya state affects penguin breeding success, adult survival, and population growth. The team will conduct idealized sensitivity analysis to explore implications of forcing variability, including local and large-scale environmental change, on Antarctic coastal ecosystems.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; Animal Behavior; Penguin; FIELD INVESTIGATION; USAP-DC; COASTAL; PENGUINS; SEA ICE; Antarctica; OCEAN MIXED LAYER", "locations": "Southern Ocean; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Integrated System Science", "paleo_time": null, "persons": "Zhang, Weifeng; Ji, Rubao; Jenouvrier, Stephanie; Maksym, Edward; Li, Yun", "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: Polynyas in Coastal Antarctica (PICA): Linking Physical Dynamics to Biological Variability", "uid": "p0010044", "west": -180.0}, {"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": "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"}, {"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": "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": "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": "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": "001508", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0807"}, {"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": "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": "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": "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": "001509", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0806"}], "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. 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 REU 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": "Schoof, Christian; DeConto, Robert; Das, Indrani; Bell, Robin; Banwell, Alison; Lenaerts, Jan; Trusel, Luke; Kingslake, Jonathan; Tedesco, Marco", "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 and review paper that will be broadly distributed.", "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": "1341339 Baker, Bill; 1341333 McClintock, James", "bounds_geometry": "POLYGON((-65 -65,-64.8 -65,-64.6 -65,-64.4 -65,-64.2 -65,-64 -65,-63.8 -65,-63.6 -65,-63.4 -65,-63.2 -65,-63 -65,-63 -64.9,-63 -64.8,-63 -64.7,-63 -64.6,-63 -64.5,-63 -64.4,-63 -64.3,-63 -64.2,-63 -64.1,-63 -64,-63.2 -64,-63.4 -64,-63.6 -64,-63.8 -64,-64 -64,-64.2 -64,-64.4 -64,-64.6 -64,-64.8 -64,-65 -64,-65 -64.1,-65 -64.2,-65 -64.3,-65 -64.4,-65 -64.5,-65 -64.6,-65 -64.7,-65 -64.8,-65 -64.9,-65 -65))", "dataset_titles": "Data from Amsler et al. 2019 Antarctic Science; Plocamium cartilagineum field chemotyping; Plocamium reproductive system data and R code; Plocamium transect and transplant data; Raw gastropod collection data from Amsler et al. 2022 Antarctic Science; Supplementary information provided with Murray et al.: Discovery of an Antarctic ascidian-associated uncultivated Verrucomicrobia with antimelanoma palmerolide biosynthetic potential; Synoicum adareanum sampling underwater video Mar 2011 Palmer Station Antarctica; The Chemical Ecology of Shallow-water Marine Macroalgae and Invertebrates on the Antarctic Peninsula - 2010 experimental data; The Chemical Ecology of Shallow-water Marine Macroalgae and Invertebrates on the Antarctic Peninsula - 2010 field data; The Chemical Ecology of Shallow-water Marine Macroalgae and Invertebrates on the Antarctic Peninsula - 2011 Clad Outplant; The Chemical Ecology of Shallow-water Marine Macroalgae and Invertebrates on the Antarctic Peninsula - 2013 Chemo Phylo data", "datasets": [{"dataset_uid": "601533", "doi": "10.15784/601533", "keywords": "Antarctica; Benthos; Palmer Station", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Raw gastropod collection data from Amsler et al. 2022 Antarctic Science", "url": "https://www.usap-dc.org/view/dataset/601533"}, {"dataset_uid": "601622", "doi": "10.15784/601622", "keywords": "Antarctica; Benthic; Biota; Macroalgae; Population Genetics", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Plocamium reproductive system data and R code", "url": "https://www.usap-dc.org/view/dataset/601622"}, {"dataset_uid": "601215", "doi": "10.15784/601215", "keywords": "Algae; Antarctica; Biota; Chemical Ecology; Chemotyping; Halogenated Monoterpenes; Natural Products; Oceans; Palmer Station; Plocamium Cartilagineum; Southern Ocean; Terpenes", "people": "Baker, Bill", "repository": "USAP-DC", "science_program": null, "title": "Plocamium cartilagineum field chemotyping", "url": "https://www.usap-dc.org/view/dataset/601215"}, {"dataset_uid": "601159", "doi": "601159", "keywords": "Antarctica; Benthic; Biota; Macroalgae; Mesograzer; Microscopy; Oceans; Zooplankton", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Data from Amsler et al. 2019 Antarctic Science", "url": "https://www.usap-dc.org/view/dataset/601159"}, {"dataset_uid": "200357", "doi": "10.5061/dryad.gxd2547gw", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Synoicum adareanum sampling underwater video Mar 2011 Palmer Station Antarctica", "url": "https://datadryad.org/stash/dataset/doi:10.5061/dryad.gxd2547gw"}, {"dataset_uid": "601621", "doi": "10.15784/601621", "keywords": "Antarctica; Benthic; Biota; Macroalgae; Mesograzer; Microscopy; Oceans; Secondary Metabolites", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Plocamium transect and transplant data", "url": "https://www.usap-dc.org/view/dataset/601621"}, {"dataset_uid": "600047", "doi": "10.15784/600047", "keywords": "Antarctica; Biota; Oceans; Southern Ocean", "people": "Baker, Bill", "repository": "USAP-DC", "science_program": null, "title": "The Chemical Ecology of Shallow-water Marine Macroalgae and Invertebrates on the Antarctic Peninsula - 2010 experimental data", "url": "https://www.usap-dc.org/view/dataset/600047"}, {"dataset_uid": "600095", "doi": "10.15784/600095", "keywords": "Algae; Antarctica; Antarctic Peninsula; Biota; Oceans; Southern Ocean", "people": "Amsler, Charles; McClintock, James", "repository": "USAP-DC", "science_program": null, "title": "The Chemical Ecology of Shallow-water Marine Macroalgae and Invertebrates on the Antarctic Peninsula - 2011 Clad Outplant", "url": "https://www.usap-dc.org/view/dataset/600095"}, {"dataset_uid": "600096", "doi": "10.15784/600096", "keywords": "Algae; Antarctica; Antarctic Peninsula; Biota; Oceans; Southern Ocean", "people": "Baker, Bill", "repository": "USAP-DC", "science_program": null, "title": "The Chemical Ecology of Shallow-water Marine Macroalgae and Invertebrates on the Antarctic Peninsula - 2013 Chemo Phylo data", "url": "https://www.usap-dc.org/view/dataset/600096"}, {"dataset_uid": "600046", "doi": "10.15784/600046", "keywords": "Antarctica; Biota; Oceans; Southern Ocean", "people": "McClintock, James; Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "The Chemical Ecology of Shallow-water Marine Macroalgae and Invertebrates on the Antarctic Peninsula - 2010 field data", "url": "https://www.usap-dc.org/view/dataset/600046"}, {"dataset_uid": "200356", "doi": "10.5061/dryad.8sf7m0cpp", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Supplementary information provided with Murray et al.: Discovery of an Antarctic ascidian-associated uncultivated Verrucomicrobia with antimelanoma palmerolide biosynthetic potential", "url": "https://datadryad.org/stash/dataset/doi:10.5061/dryad.8sf7m0cpp"}], "date_created": "Tue, 05 Mar 2019 00:00:00 GMT", "description": "The coastal environments of the western Antarctic Peninsula harbor rich assemblages of marine animals and algae. The importance of the interactions between these groups of organisms in the ecology of coastal Antarctica are well known and often mediated by chemical defenses in the tissues of the algae. These chemicals are meant to deter feeding by snails and other marine animals making the Antarctic Peninsula an excellent place to ask important questions about the functional and evolutionary significance of chemical compound diversity for marine communities. This project will focus on three main objectives: the first objective is to expand the current understanding of the relationship between algae and their associated marine animals. The second objective focuses on the diversity of chemical compounds used to defend algae from being consumed. The third objective seeks to understand how marine animals can benefit from these compounds by consuming the algae that contain them, and then using those compounds to chemically deter predators. The field components of this research will be performed during three expeditions to the US Palmer Station, Antarctica. During these expeditions, a variety of laboratory feeding bioassays, manipulative field and laboratory experiments, and on-site chemical analyses will be performed. The investigators will also foster opportunities to integrate their NSF research with a variety of educational activities. As in the past they will support undergraduate research, both through NSF programs as well as home, university-based, programs, and they will also continue to support and foster graduate education. Through their highly successful University of Alabama in Antarctica interactive web program (two time recipient of awards of excellence from the US Council for Advancement and Support of Education), they will continue to involve large numbers of teachers, K-12 students, and other members of the community at large in their scientific endeavors in Antarctica. In addition, the investigators have hosted K-12 teachers on their Antarctic field teams through the former NSF Teachers Experiencing Antarctica and the Arctic program and will pursue participation in PolarTREC, the successor to this valuable program. Moreover, they will actively participate in outreach efforts by presenting numerous talks on their research to local school and community groups. The near shore environments of the western Antarctic Peninsula harbor rich assemblages of macroalgae and macroinvertebrates. The importance of predator-prey interactions and chemical defenses in mediating community-wide trophic interactions makes the western Antarctic Peninsula an excellent place to ask important questions about the functional and evolutionary significance of defensive compound diversity for marine communities. This project will focus on three main objectives which are a direct outcome of the past studies of the chemical ecology of shallow-water marine macroalgae and invertebrates on the Antarctic Peninsula by this group of investigators. The first objective is to expand the current understanding of a community-wide mutualism between macroalgae and their associated amphipods to include gastropods, which are also abundant on many macroalgae. The second objective focuses on the diversity of chemical compounds used to defend macroalgae from being consumed, particularly in the common red alga Plocamium cartilagineum. The third objective seeks to understand the relationship between P. cartilagineum and the amphipod Paradexamine fissicauda, including the ecological benefits and costs to P. fissicauda resulting from the ability to consume P. cartilagineum and other chemically defended red algae. The investigators will focus on the costs and benefits related to the ability of P. fissicauda to sequester defensive compounds from the alga P. cartilagineum and use those chemicals to defend itself from predation. The field components of this research will be performed during three expeditions to Palmer Station, Antarctica. During these expeditions, a variety of laboratory feeding bioassays, manipulative field and laboratory experiments, and on-site chemical analyses will be performed. Phylogenetic analyses, detailed secondary metabolite chemical analyses and purifications, and other data analyses will also be performed at the investigators\u0027 home institutions between and after their field seasons.", "east": -63.0, "geometry": "POINT(-64 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; Antarctica; BENTHIC; USAP-DC", "locations": "Antarctica", "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Amsler, Charles; Baker, Bill; McClintock, James", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "Dryad; USAP-DC", "science_programs": null, "south": -65.0, "title": "Collaborative Research: The Chemical Ecology of Shallow-water Marine Macroalgae and Invertebrates on the Antarctic Peninsula - continuing", "uid": "p0010016", "west": -65.0}, {"awards": "1341612 Bowser, Samuel", "bounds_geometry": null, "dataset_titles": "Aerial survey of Explorers Cove shoreline, late January 2005; Astrammina rara genome sequencing and assembly; Astrammina triangularis genome sequencing and assembly; Crithionina delacai mitochondrial genome sequence and assembly; Scanning electron micrographs: Influence of heavy metal (Pb, Cd) exposure on shell morphogenesis in Astrammina rara, a giant agglutinated Antarctic foraminiferan protist", "datasets": [{"dataset_uid": "601229", "doi": "10.15784/601229", "keywords": "Aerial Imagery; Antarctica; Camera; Delta; Freshwater; Helicopter; Moat; Shoreline Survey; Small Ponds; Snow Melt; Tide Pools", "people": "Bowser, Samuel; Alexander, Steve", "repository": "USAP-DC", "science_program": null, "title": "Aerial survey of Explorers Cove shoreline, late January 2005", "url": "https://www.usap-dc.org/view/dataset/601229"}, {"dataset_uid": "200089", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Astrammina triangularis genome sequencing and assembly", "url": "https://dataview.ncbi.nlm.nih.gov/object/PRJNA521279?reviewer=g418tpq02sif2g6do94dpmmjdv"}, {"dataset_uid": "601138", "doi": "10.15784/601138", "keywords": "Antarctica; Biota; Foraminifera; Heavy Metal Toxicity; Scanning Electron Microscop; Scanning Electron Microscope (SEM) Images; Scanning Electron Microscopy; Transantarctic Mountains", "people": "Bowser, Samuel; Andreas, Amanda", "repository": "USAP-DC", "science_program": null, "title": "Scanning electron micrographs: Influence of heavy metal (Pb, Cd) exposure on shell morphogenesis in Astrammina rara, a giant agglutinated Antarctic foraminiferan protist", "url": "https://www.usap-dc.org/view/dataset/601138"}, {"dataset_uid": "200090", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Astrammina rara genome sequencing and assembly", "url": "https://dataview.ncbi.nlm.nih.gov/object/PRJNA521081?reviewer=25e190ih1svottjkrrpfa7huoe"}, {"dataset_uid": "200091", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Crithionina delacai mitochondrial genome sequence and assembly", "url": "https://dataview.ncbi.nlm.nih.gov/object/PRJNA592714?reviewer=ivse8455h3gfaiilg4nqle0vm1"}], "date_created": "Thu, 29 Nov 2018 00:00:00 GMT", "description": "Agglutinated foraminifera (forams for short) are early-evolving, single-celled organisms. These \"living fossils\" construct protective shells using sediment grains held together by adhesive substances that they secrete. During shell construction, agglutinated forams display amazing properties of selection - for example, some species build their shells of clear quartz grains, while other species use only grains of a specific size. Understanding how these single cells assemble complex structures may contribute to nanotechnology by enabling people to use forams as \"cellular machines\" to aid in the construction of nano-devices. This project will analyze the genomes of at least six key foram species, and then \"mine\" these genomes for technologically useful products and processes. The project will focus initially on the adhesive materials forams secrete, which may have wide application in biomedicine and biotechnology. Furthermore, the work will further develop a molecular toolkit which could open up new avenues of research on the physiology, ecology, and population dynamics of this important group of Antarctic organisms. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. Educational experiences related to the \"thrill of scientific exploration and discovery\" for students and the general public will be provided through freely-available short films and a traveling art/science exhibition. The project will also provide hands-on research opportunities for undergraduate students. Explorers Cove, situated on the western shore of McMurdo Sound, harbors a unique population of foraminiferan taxa at depths accessible by scuba diving that otherwise are primarily found in the deep sea. The project will use next-generation DNA sequencing and microdissection methods to obtain and analyze nuclear and mitochondrial genomes from crown members of two species each from three distinct, early-evolving foraminiferal groups. It will also use next generation sequencing methods to characterize the in-situ prokaryotic assemblages (microbiomes) of one of these groups and compare them to reference sediment microbiomes. The phyogenomic studies of the targeted Antarctic genera will help fill significant gaps in our current understanding of early foram evolution. Furthermore, comparative genomic analyses of these six species are expected to yield a better understanding of the physiology of single-chambered agglutinated forams, especially the bioadhesive proteins and regulatory factors involved in shell composition and morphogenesis. Additionally, the molecular basis of cold adaptation in forams will be examined, particularly with respect to key proteins.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; NOT APPLICABLE", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Bowser, Samuel", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "NCBI GenBank; USAP-DC", "science_programs": null, "south": null, "title": "Assembling and Mining the Genomes of Giant Antarctic Foraminifera", "uid": "p0000004", "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": "Walker, Ben; Kaluzienski, Lynn; Lever, Jim; Ray, Laura; Koons, Peter; Arcone, Steven", "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": "Hamilton/1246400 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": "1443126 MacAyeal, Douglas", "bounds_geometry": "POLYGON((166.1631 -77.9007,166.19736 -77.9007,166.23162 -77.9007,166.26588 -77.9007,166.30014 -77.9007,166.3344 -77.9007,166.36866 -77.9007,166.40292 -77.9007,166.43718 -77.9007,166.47144 -77.9007,166.5057 -77.9007,166.5057 -77.90423,166.5057 -77.90776,166.5057 -77.91129,166.5057 -77.91482,166.5057 -77.91835,166.5057 -77.92188,166.5057 -77.92541,166.5057 -77.92894,166.5057 -77.93247,166.5057 -77.936,166.47144 -77.936,166.43718 -77.936,166.40292 -77.936,166.36866 -77.936,166.3344 -77.936,166.30014 -77.936,166.26588 -77.936,166.23162 -77.936,166.19736 -77.936,166.1631 -77.936,166.1631 -77.93247,166.1631 -77.92894,166.1631 -77.92541,166.1631 -77.92188,166.1631 -77.91835,166.1631 -77.91482,166.1631 -77.91129,166.1631 -77.90776,166.1631 -77.90423,166.1631 -77.9007))", "dataset_titles": "McMurdo Ice Shelf AWS data; McMurdo Ice Shelf GPS survey of vertical motion; Supraglacial Lake Depths on McMurdo Ice Shelf, Antarctica; Time-lapse video of McMurdo Ice Shelf surface melting and hydrology", "datasets": [{"dataset_uid": "601113", "doi": "10.15784/601113", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Shelf; Photo/video; Photo/Video; Supraglacial Meltwater", "people": "Banwell, Alison; MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Time-lapse video of McMurdo Ice Shelf surface melting and hydrology", "url": "https://www.usap-dc.org/view/dataset/601113"}, {"dataset_uid": "601107", "doi": "10.15784/601107", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ice Flow Velocity; Ice Shelf; Ice-Shelf Flexure; Snow/ice; Snow/Ice; Surface Melt", "people": "MacAyeal, Douglas; Banwell, Alison", "repository": "USAP-DC", "science_program": null, "title": "McMurdo Ice Shelf GPS survey of vertical motion", "url": "https://www.usap-dc.org/view/dataset/601107"}, {"dataset_uid": "601106", "doi": "10.15784/601106", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hydrology; Ice Shelf; Snow/ice; Snow/Ice; Surface Hydrology; Surface Mass Balance; Weather Station Data", "people": "Banwell, Alison; MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "McMurdo Ice Shelf AWS data", "url": "https://www.usap-dc.org/view/dataset/601106"}, {"dataset_uid": "601116", "doi": "10.15784/601116", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Shelf; Snow/ice; Snow/Ice; Subglacial And Supraglacial Water Depth; Supraglacial Lake; Supraglacial Meltwater; Water Depth", "people": "MacAyeal, Douglas; Banwell, Alison", "repository": "USAP-DC", "science_program": null, "title": "Supraglacial Lake Depths on McMurdo Ice Shelf, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601116"}], "date_created": "Tue, 24 Jul 2018 00:00:00 GMT", "description": "Meltwater lakes that sit on top of Antarctica\u0027s floating ice shelves have likely contributed to the dramatic changes seen in Antarctica\u0027s glacial ice cover over the past two decades. In 2002, the 1,600-square-kilometer Larsen B Ice Shelf located on the Eastern side of the Antarctic Peninsula, for example, broke into thousands of small icebergs, which subsequently floated away as a result of the formation of more than 2,000 meltwater lakes on its surface over the prior decade. Our research project addresses the reasons why surface lakes form on Antarctic ice shelves and how these surface lakes subsequently contribute to the forces that may contribute to ice-shelf breakup like that of the Larsen B. Our project focuses primarily on making precise global positioning system (GPS) measurements of ice-shelf bending in response to the filling and draining of a surface lake on the McMurdo Ice Shelf. The observed vertical displacements (on the order of tens of centimeters) in response to lake filling will be used to calibrate and test computer simulation models that predict the response of ice shelves to surface lakes more generally and in a variety of future climate conditions. Our project will make hourly measurements of both vertical ice-shelf movements (using GPS surveying instruments) and of temperature and sunlight conditions (that drive melting) around a surface lake located close to the McMurdo Station airfield. Following this initial data-gathering effort, computer simulations and other more theoretical analysis will be undertaken to determine the suitability of the chosen McMurdo Ice Shelf surface lake as a field-laboratory for continued study. Ultimately, the research will contribute to understanding of the glaciological processes that link climate change to rising sea level. A successful outcome of the research will allow glaciologists to better assess the processes that promote or erode the influence Antarctic ice shelves have in controlling the transfer of ice from the interior of Antarctica into the ocean. The project will undertake two outreach activities: (1) web-posting of a field-activity journal and (2) establishing an open-access glaciological teaching and outreach web-sharing site for the International Glaciological Society. The proposed project seeks to experimentally verify a theory of ice-shelf instability proposed to explain the explosive break-up of Larsen B Ice Shelf in 2002. This theory holds that the filling and draining of supraglacial lakes on floating ice shelves induces sufficient flexure stress within the ice to (a) induce upward/downward propagating fractures originating at the base/surface of the ice shelf that (b) dissect the ice shelf into fragments that tend to have widths less than about half the ice thickness. The significance of narrow widths is that they promote capsize of the ice-shelf fragments during the break-up process. This capsize releases large amounts of gravitational potential energy (comparable to thousands of kilotons of TNT for the Larsen B Ice Shelf) thereby promoting explosiveness of the Larsen B event. The observational motivation for experimentally verifying the surface-lake mechanism for ice-shelf breakup is based on the fact that \u003e2,000 surface lakes developed on the Larsen B Ice Shelf in the decade prior to its break up, and that these lakes were observed (via satellite imagery) to drain in a coordinated fashion during the day prior to the initiation of the break up. The field-observation component of the project will focus on a supraglacial lake on the McMurdo Ice Shelf where there is persistent summer season surface melting. The lake will be studied during a single provisional field season to determine whether grooming of surrounding surface streams and shorelines with heavy construction equipment will allow surface water to be manually encouraged to fill the lake. If successfully encouraged to develop, the McMurdo Ice Shelf surface lake will allow measurements of key ice-shelf flexure and stress variables needed to develop the theory of ice-shelf surface lakes without having to access the much more logistically demanding surface lakes of ice-shelves located elsewhere in Antarctica. Data to be gathered during the 6-week provisional field season include: energy- and water-balance parameters determining how the surface lake grows and fills, and various global positioning system measurements of the vertical bending of the ice sheet in response to the changing meltwater load contained within the surface lake. These data will be used to (1) constrain a computer model of viscoelastic flexure and possible fracture of the ice shelf in response to the increasing load of meltwater in the lake, and (2) determine whether continued study of the incipient surface-meltwater lake features on the McMurdo Ice Shelf provides a promising avenue for constraining the more-general behavior of surface meltwater lakes on other ice shelves located in warmer parts of Antarctica. Computer models constrained by the observational data obtained from the field project will inform energy- and water-balance models of ice shelves in general, and allow more accurate forecasts of changing ice-shelf conditions surrounding the inland ice of Antarctica. The project will create the first-ever ground-based observations useful for spawning the development of models capable of predicting viscoelastic and fracture behavior of ice shelves in response to supraglacial lake evolution, including slow changes due to energy balance effects, as well as fast changes due to filling and draining.", "east": 166.5057, "geometry": "POINT(166.3344 -77.91835)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS", "is_usap_dc": true, "keywords": "USAP-DC; AWOS", "locations": null, "north": -77.9007, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "MacAyeal, Douglas", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e AWOS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.936, "title": "Impact of Supraglacial Lakes on Ice-Shelf Stability", "uid": "p0000138", "west": 166.1631}, {"awards": "0944021 Brook, Edward J.; 0944307 Conway, Howard; 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": "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": "Hawley, Robert L.; Clemens-Sewall, David; 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": "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"}, {"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": "601086", "doi": "10.15784/601086", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Roosevelt Island; Snow/ice; Snow/Ice", "people": "Clemens-Sewall, David; Hawley, Robert L.", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Borehole Optical Televiewer logs", "url": "https://www.usap-dc.org/view/dataset/601086"}], "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 Glaciology; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences", "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": "1141936 Foreman, Christine", "bounds_geometry": "POINT(112.085 -79.467)", "dataset_titles": "Molecular Level Characterization of Dissolved Organic Carbon and Microbial Diversity in the WAIS Divide Replicate Core", "datasets": [{"dataset_uid": "600133", "doi": "10.15784/600133", "keywords": "Antarctica; Biota; Genetic Sequences; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "people": "Foreman, Christine", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Molecular Level Characterization of Dissolved Organic Carbon and Microbial Diversity in the WAIS Divide Replicate Core", "url": "https://www.usap-dc.org/view/dataset/600133"}], "date_created": "Thu, 05 Nov 2015 00:00:00 GMT", "description": "This award supports a detailed, molecular level characterization of dissolved organic carbon and microbes in Antarctic ice cores. Using the most modern biological (genomic), geochemical techniques, and advanced chemical instrumentation researchers will 1) optimize protocols for collecting, extracting and amplifying DNA from deep ice cores suitable for use in next generation pyrosequencing; 2) determine the microbial diversity within the ice core; and 3) obtain and analyze detailed molecular characterizations of the carbon in the ice by ultrahigh resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS). With this pilot study investigators will be able to quantify the amount of material (microbial biomass and carbon) required to perform these characterizations, which is needed to inform future ice coring projects. The ultimate goal will be to develop protocols that maximize the yield, while minimizing the amount of ice required. The broader impacts include education and outreach at both the local and national levels. As a faculty mentor with the American Indian Research Opportunities and BRIDGES programs at Montana State University, Foreman will serve as a mentor to a Native American student in the lab during the summer months. Susan Kelly is an Education and Outreach Coordinator with a MS degree in Geology and over 10 years of experience in science outreach. She will coordinate efforts for comprehensive educational collaboration with the Hardin School District on the Crow Indian Reservation in South-central Montana.", "east": 112.085, "geometry": "POINT(112.085 -79.467)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ADS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Dissolved Organic Carbon; Microbes; Ice Core; Not provided; Pyrosequencing; Microbial Diversity; Molecular; WAIS Divide; LABORATORY; FIELD SURVEYS; Antarctic; FIELD INVESTIGATION; DNA", "locations": "Antarctic; WAIS Divide", "north": -79.467, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Foreman, Christine", "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": -79.467, "title": "Molecular Level Characterization of Dissolved Organic Carbon and Microbial Diversity in the WAIS Divide Replicate Core", "uid": "p0000342", "west": 112.085}, {"awards": "1043522 Brook, Edward J.; 1043421 Severinghaus, Jeffrey", "bounds_geometry": "POINT(-112.09 -79.47)", "dataset_titles": "WAIS Divide Replicate Core Methane Isotopic Data Set", "datasets": [{"dataset_uid": "601059", "doi": "10.15784/601059", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Replicate Core Methane Isotopic Data Set", "url": "https://www.usap-dc.org/view/dataset/601059"}], "date_created": "Mon, 13 Jul 2015 00:00:00 GMT", "description": "1043421/Severinghaus This award supports a project to obtain samples of ice in selected intervals for replication and verification of the validity and spatial representativeness of key results in the WAIS Divide ice core, and to obtain additional ice samples in areas of intense scientific interest where demand is high. The US Ice Core Working Group recommended in 2003 that NSF pursue the means to take replicate samples, termed \"replicate coring\". This recommendation was part of an agreement to reduce the diameter of the (then) new drilling system (the DISC drill) core to 12.2 cm to lighten logistics burdens, and the science community accepted the reduction in ice sample with the understanding that replicate coring would be able to provide extra sample volume in key intervals. The WAIS Divide effort would particularly benefit from replicate coring, because of the unique quality of the expected gas record and the large samples needed for gases and gas isotopes; thus this proposal to employ replicate coring at WAIS Divide. In addition, scientific demand for ice samples has been, and will continue to be, very unevenly distributed, with the ice core archive being completely depleted in depth intervals of high scientific interest (abrupt climate changes, volcanic sulfate horizons, meteor impact horizons, for example). The broader impacts of the proposed research may include identification of leads and lags between Greenland, tropical, and Antarctic climate change, enabling critical tests of hypotheses for the mechanism of abrupt climate change. Improved understanding of volcanic impacts on atmospheric chemistry and climate may also emerge. This understanding may ultimately help improve climate models and prediction of the Earth System feedback response to ongoing human perturbation in coming centuries. Outreach and public education about climate change are integral components of the PIs\u0027 activities and the proposed work will enhance these efforts. Broader impacts also include education and training of 2 postdoctoral scholars and 1 graduate student, and invaluable field experience for the graduate and undergraduate students who will likely make up the core processing team at WAIS Divide.", "east": -112.09, "geometry": "POINT(-112.09 -79.47)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": false, "keywords": "Ice Core Gas Records; Firn Air Isotopes; LABORATORY; FIELD SURVEYS; Mass Spectrometry; Not provided; FIELD INVESTIGATION; Ice Core; WAIS Divide", "locations": "WAIS Divide", "north": -79.47, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.; Brook, Edward 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": -79.47, "title": "Collaborative Research: Replicate Coring at WAIS Divide to Obtain Additional Samples at Events of High Scientific Interest", "uid": "p0000751", "west": -112.09}, {"awards": "0944193 MacAyeal, Douglas", "bounds_geometry": null, "dataset_titles": "Iceberg Capsize Kinematics and Energetics", "datasets": [{"dataset_uid": "609590", "doi": "10.7265/N56H4FCJ", "keywords": "Antarctica; Glaciology; Iceberg; Kinetics", "people": "MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Iceberg Capsize Kinematics and Energetics", "url": "https://www.usap-dc.org/view/dataset/609590"}], "date_created": "Mon, 25 Aug 2014 00:00:00 GMT", "description": "This award supports a project to examine and test a 3-step process model for explosive ice-shelf disintegration that emerged in the wake of the recent 2008 and 2009 events of the Wilkins Ice Shelf. The model is conditioned on Summer melt-driven increase in free-surface water coupled with surface and basal crevasse density growth necessary to satisfy an \"enabling condition\". Once met, the collapse proceeds through three steps: (Step 1), calving of a \"leading phalanx\" of tabular icebergs from the seaward ice front of the ice shelf which creates in its wake a region, called a \"mosh pit\" (located between the phalanx and the edge of the intact ice shelf), where ocean surface-gravity waves are trapped by reflection (a fast mechanically enabled process), (Step 2), and a rapid, runaway conversion of gravitational potential energy into ocean-wave energy by iceberg capsize and fragmentation within the \"mosh pit\" which leads to further wave-induced calving, capsize and fragmentation (Step 3). The project will be conducted by a multidisciplinary team and will focus on theoretical model development, numerical method development and application and new observations. The project will participate in both the Research Experience for Undergraduates program in the Physics Department and the Summer Research Early Identification Program (SR-EIP) that fosters participation in research by underrepresented minorities. The PIs, postdoctoral scholar, graduate students and unfunded participants will develop a graduate-level seminar/tutorial to introduce advanced computational methods to glaciology. A postdoctoral scholar and graduate student will be trained in new research techniques during the project.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e VIDEO CAMERA", "is_usap_dc": true, "keywords": "LABORATORY; Iceberg Kinetic Energy; Iceberg Velocity", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "MacAyeal, Douglas", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Explosive Ice-Shelf Disintegration", "uid": "p0000005", "west": null}, {"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": "0944248 MacAyeal, Douglas", "bounds_geometry": "POLYGON((-63.72 -63.73,-62.893 -63.73,-62.066 -63.73,-61.239 -63.73,-60.412 -63.73,-59.585 -63.73,-58.758 -63.73,-57.931 -63.73,-57.104 -63.73,-56.277 -63.73,-55.45 -63.73,-55.45 -64.0876,-55.45 -64.4452,-55.45 -64.8028,-55.45 -65.1604,-55.45 -65.518,-55.45 -65.8756,-55.45 -66.2332,-55.45 -66.5908,-55.45 -66.9484,-55.45 -67.306,-56.277 -67.306,-57.104 -67.306,-57.931 -67.306,-58.758 -67.306,-59.585 -67.306,-60.412 -67.306,-61.239 -67.306,-62.066 -67.306,-62.893 -67.306,-63.72 -67.306,-63.72 -66.9484,-63.72 -66.5908,-63.72 -66.2332,-63.72 -65.8756,-63.72 -65.518,-63.72 -65.1604,-63.72 -64.8028,-63.72 -64.4452,-63.72 -64.0876,-63.72 -63.73))", "dataset_titles": "Go to the NSIDC and search for the data.; Standing Water Depth on Larsen B Ice Shelf", "datasets": [{"dataset_uid": "609584", "doi": "10.7265/N500002K", "keywords": "Antarctica; Antarctic Peninsula; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Shelf; Larsen B Ice Shelf; Sample/collection Description; Sample/Collection Description; Supraglacial Meltwater", "people": "MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Standing Water Depth on Larsen B Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/609584"}, {"dataset_uid": "001996", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "Go to the NSIDC and search for the data.", "url": "http://nsidc.org"}], "date_created": "Sat, 21 Dec 2013 00:00:00 GMT", "description": "MacAyeal/0944248\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop a better understanding of the processes and conditions that trigger ice shelf instability and explosive disintegration. A significant product of the proposed research will be the establishment of parameterizations of micro- and meso-scale ice-shelf surface processes needed in large scale ice-sheet models designed to predict future sea level rise. The proposed research represents a 3-year effort to conduct numerical model studies of 6 aspects of surface-water evolution on Antarctic ice shelves. These 6 model-study areas include energy balance models of melting ice-shelf surfaces, with treatment of surface ponds and water-filled crevasses, distributed, Darcian water flow modeling to simulate initial firn melting, brine infiltration, pond drainage and crevasse filling, ice-shelf surface topography evolution modeling by phase change (surface melting and freezing), surface-runoff driven erosion and seepage flows, mass loading and flexure effects of ice-shelf and iceberg surfaces; feedbacks between surface-water loads and flexure stresses; possible seiche phenomena of the surface water, ice and underlying ocean that constitute a mechanism for, inducing surface crevassing., surface pond and crevasse convection, and basal crevasse thermohaline convection (as a phenomena related to area 5 above). The broader impacts of the proposed work bears on the socio-environmental concerns of climate change and sea-level rise, and will contribute to the important goal of advising public policy. The project will form the basis of a dissertation project of a graduate student whose training will contribute to the scientific workforce of the nation and the PI and graduate student will additionally participate in a summer science-enrichment program for high-school teachers organized by colleagues at the University of Chicago.", "east": -55.45, "geometry": "POINT(-59.585 -65.518)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e ETM+; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e PHOTOMETERS \u003e SPECTROPHOTOMETERS", "is_usap_dc": true, "keywords": "Supraglacial Lake; LANDSAT-7; Melt Ponds; Standing Water Depth; Ice Shelf Stability", "locations": null, "north": -63.73, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "MacAyeal, Douglas", "platforms": "SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e LANDSAT \u003e LANDSAT-7", "repo": "USAP-DC", "repositories": "NSIDC; USAP-DC", "science_programs": null, "south": -67.306, "title": "Model Studies of Surface Water Behavior on Ice Shelves", "uid": "p0000052", "west": -63.72}, {"awards": "1043367 Aciego, Sarah", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 01 Nov 2013 00:00:00 GMT", "description": "Aciego/1043367 This award supports the development of a new method for determining the absolute age of samples from deep ice cores. The project will: (1) prove the efficacy of the Uranium-series dating method on a high accumulation rate ice core, and (2) address the uncertainties in the age dating of the EPICA Dronning-Maud Land (EDML) ice core in the lower 300 m. The well-dated upper section of the ice core (down to 150,000 years at 2415.7 m) will provide excellent constraints to validate the ages determined by the U-series method. After verification, and possible adjustments to the laboratory chemistry, the method will be applied to a suite of ice samples of unknown age in the lower part of the EDML ice core. Within the lower 300 m of this ice core, the climate records are disturbed by tilting and folding of the ice, and, due to the uncertainties in how the ice has flowed, it is impossible to determine if accurate age dates can be obtained to access the record of climate change, or if mixing of the ice is too incoherent. As part of the methodology, the PI will measure surface area of dust included in the ice using a gas adsorption technique developed for ultra-small samples; these measurements will be made on a BET nano-scale which is to be purchased from the funding of this project. Intellectual Merit: The proposed research will contribute to our understanding of geophysical processes that fold and tilt ice. This will allow new paleoclimate records to be recovered from ice cores that have been physically deformed and disturbed and previously did not permit accurate dating. Broader Impacts: This funding will provide support for one PhD graduate student and contribute to their training as a researcher in geochemistry and paleoclimate studies. The PI will teach classes in earth surface processes (including glaciology) and in advanced isotope geochemistry. Work related to this research will be integrated as a teaching tool into the classroom to provide a hands-on, relevant learning experience. Furthermore, samples examined as part of this research will be made available from the AWI archive in Bremerhaven, Germany as part of the collaboration between the PI in the United States and the European ice core community.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Instrumentation and Support", "paleo_time": null, "persons": "Aciego, Sarah", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Detangling Flow Regimes and Paleoclimate in the Deepest Section of the EDML Ice Core using U-series Ages.", "uid": "p0000712", "west": null}, {"awards": "9527255 Mopper, Kenneth", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG9809", "datasets": [{"dataset_uid": "002719", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG9809", "url": "https://www.rvdata.us/search/cruise/LMG9809"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "ACT K. Mopper \u0026 D. Kieber OPP 9527255 \u0026 OPP 9527314 PHOTOCHEMICAL AND OPTICAL PROPERTIES OF ANTARCTIC WATERS IN RESPONSE TO CHANGING UV-B FLUXES The decrease in stratospheric ozone over the Antarctic results in an increase in the UV-B flux in the euphotic zone. The increase leads to cellular damage to aquatic organisms, as documented by photo-inhibition and decreased productivity. Cellular damage can occur either intracellularly, or externally at the cell surface from biomolecular reactions with externally-generated reactive transients. The extent of this extracellular damage will depend on the photochemistry of the seawater surrounding the cell. Until recently, nothing was known about the type of photochemical processes, rates, and steady state concentrations of transients in Antarctic waters. It is proposed that field experiments be performed which will allow the construction of predictive models of photochemical production rates in surface waters and with depth. These studies will involve further quantum yield measurementts, development of a sensitive underwater actinometer system, and use of a new underwater multichannel photometer. The model will allow the prediction of the impact of varying levels of UV-B on the photoproduction and steady state concentration of several key reactive transient species in the upper water column. In addition to this effort, experiments will also be performed to study the photodegradation of dissolved organic matter and to determine whether biologically utilizable substrates that are formed photochemically can enhance secondary productivity in Antarctic waters.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Mopper, Kenneth", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Photochemical and Optical Properties of Antarctic Waters in Response to Changing UV-B Fluxes", "uid": "p0000870", "west": null}, {"awards": "0125890 Sidell, Bruce", "bounds_geometry": "POLYGON((-68.1413 -52.6755,-67.47503 -52.6755,-66.80876 -52.6755,-66.14249 -52.6755,-65.47622 -52.6755,-64.80995 -52.6755,-64.14368 -52.6755,-63.47741 -52.6755,-62.81114 -52.6755,-62.14487 -52.6755,-61.4786 -52.6755,-61.4786 -53.8957,-61.4786 -55.1159,-61.4786 -56.3361,-61.4786 -57.5563,-61.4786 -58.7765,-61.4786 -59.9967,-61.4786 -61.2169,-61.4786 -62.4371,-61.4786 -63.6573,-61.4786 -64.8775,-62.14487 -64.8775,-62.81114 -64.8775,-63.47741 -64.8775,-64.14368 -64.8775,-64.80995 -64.8775,-65.47622 -64.8775,-66.14249 -64.8775,-66.80876 -64.8775,-67.47503 -64.8775,-68.1413 -64.8775,-68.1413 -63.6573,-68.1413 -62.4371,-68.1413 -61.2169,-68.1413 -59.9967,-68.1413 -58.7765,-68.1413 -57.5563,-68.1413 -56.3361,-68.1413 -55.1159,-68.1413 -53.8957,-68.1413 -52.6755))", "dataset_titles": "Expedition Data; Expedition data of LMG0304; Expedition data of LMG0304A", "datasets": [{"dataset_uid": "002706", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0304", "url": "https://www.rvdata.us/search/cruise/LMG0304"}, {"dataset_uid": "001704", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0304"}, {"dataset_uid": "001597", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0505"}, {"dataset_uid": "001596", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0506"}, {"dataset_uid": "002707", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0304A", "url": "https://www.rvdata.us/search/cruise/LMG0304A"}, {"dataset_uid": "002708", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0304A", "url": "https://www.rvdata.us/search/cruise/LMG0304A"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Notothenioid fishes that dominate the fish fauna surrounding Antarctica have been evolving for 10-14 million years at a nearly constant body temperature of ~0C throughout their life histories. As a result, this group of animals is uniquely suited to studies aimed at understanding and identifying features of physiology and biochemistry that result from the process of evolution at cold body temperature. This project has three major objectives aimed at examining adaptations for life in cold environments: \u003cbr/\u003e\u003cbr/\u003e1. Identify the amino acid substitutions in the fatty acid-binding pocket of fatty acyl CoA synthetase (FACS) that explain its substrate specificity. Fatty acids are a major fuel of energy metabolism in Antarctic fishes. FACS catalyzes the condensation of CoASH and fatty acids to fatty acyl CoA esters, a step required for subsequent metabolism of these important compounds. This research may permit us to resolve the specific amino acid substitutions that explain both substrate specificity and preservation of catalytic rate of notothenioid FACS at cold physiological temperatures.\u003cbr/\u003e\u003cbr/\u003e2. Produce a rigorous biochemical and biophysical characterization of the intracellular calcium-binding protein, parvalbumin, from white axial musculature of Antarctic fishes. Parvalbumin plays a pivotal role in facilitating the relaxation phase of fast-contracting muscles and is a likely site of strong selective pressure. Preliminary data strongly indicate that the protein from Antarctic fishes has been modified to ensure function at cold temperature. A suite of physical techniques will be used to determine dissociation constants of Antarctic fish parvalbumins for calcium and magnesium and unidirectional rate constants of ion-dissociation from the protein. Full-length cDNA clones for Antarctic fish parvalbumin(s) will permit deduction of primary amino acid sequence These data will yield insight into structural elements that permit the protein from notothenioid fishes to function at very cold body temperature.\u003cbr/\u003e\u003cbr/\u003e3. Conduct a broad survey of the pattern of cardiac myoglobin expression in the Suborder Notothenoidei. Previous work has indicated a variable pattern of presence or absence of the intracellular oxygen-binding protein, myoglobin (Mb), in hearts of one family of Antarctic notothenioid fishes (Channichthyidae; icefishes). Because Mb is of physiological value in species that express the protein, the observed pattern of interspecific expression has been attributed to unusually low niche competition in the Southern Ocean. This leads to the prediction that similar loss of cardiac Mb should be observed in other notothenioid taxa. This part of the project will survey for the presence and absence of cardiac Mb in as many notothenioid species as possible and, if Mb-lacking species are detected, will extend analyses to determine the mechanism(s) responsible for loss of its expression using molecular biological techniques.", "east": -61.4786, "geometry": "POINT(-64.80995 -58.7765)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; 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": -52.6755, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Sidell, Bruce; Detrich, H. William", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.8775, "title": "Cold Body Temperature as an Evolutionary Shaping force in the Physiology of Antarctic Fishes", "uid": "p0000241", "west": -68.1413}, {"awards": "0440919 Isbell, John; 0440954 Miller, Molly; 0551163 Sidor, Christian", "bounds_geometry": "POLYGON((159.3 -76.59,159.542 -76.59,159.784 -76.59,160.026 -76.59,160.268 -76.59,160.51 -76.59,160.752 -76.59,160.994 -76.59,161.236 -76.59,161.478 -76.59,161.72 -76.59,161.72 -76.811,161.72 -77.032,161.72 -77.253,161.72 -77.474,161.72 -77.695,161.72 -77.916,161.72 -78.137,161.72 -78.358,161.72 -78.579,161.72 -78.8,161.478 -78.8,161.236 -78.8,160.994 -78.8,160.752 -78.8,160.51 -78.8,160.268 -78.8,160.026 -78.8,159.784 -78.8,159.542 -78.8,159.3 -78.8,159.3 -78.579,159.3 -78.358,159.3 -78.137,159.3 -77.916,159.3 -77.695,159.3 -77.474,159.3 -77.253,159.3 -77.032,159.3 -76.811,159.3 -76.59))", "dataset_titles": "Burke Museum of Natural History and Culture, University of Washington ID#s UWBM 88593-88601, UWBM 88617; Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "datasets": [{"dataset_uid": "600045", "doi": "10.15784/600045", "keywords": "Allan Hills; Antarctica; Paleontology; Sample/collection Description; Sample/Collection Description; Solid Earth", "people": "Miller, Molly", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600045"}, {"dataset_uid": "000124", "doi": "", "keywords": null, "people": null, "repository": "Burke Museum", "science_program": null, "title": "Burke Museum of Natural History and Culture, University of Washington ID#s UWBM 88593-88601, UWBM 88617", "url": "http://www.washington.edu/burkemuseum/collections/"}], "date_created": "Mon, 12 Oct 2009 00:00:00 GMT", "description": "This project studies fossils from two to three hundred million year old rocks in the Allan Hills area of Antarctica. Similar deposits from lower latitudes have been used to develop a model of Permo-Triassic climate, wherein melting of continental glaciers in the early Permian leads to the establishment of forests in a cold, wet climate. Conditions became warmer and dryer by the early Triassic, inhibiting plant growth until a moistening climate in the late Triassic allowed plant to flourish once again. This project will test and refine this model and investigate the general effects of climate change on landscapes and ecosystems using the unique exposures and well-preserved fossil and sediment records in the Allan Hills area. The area will be searched for fossil forests, vertebrate tracks and burrows, arthropod trackways, and subaqueously produced biogenic structures, which have been found in other areas of Antarctica. Finds will be integrated with previous paleobiologic studies to reconstruct and interpret ecosystems and their changes. Structures and rock types documenting the end phases of continental glaciation and other major episodic sedimentations will also be described and interpreted. This project contributes to understanding the: (1) evolution of terrestrial and freshwater ecosystems and how they were affected by the end-Permian extinction, (2) abundance and diversity of terrestrial and aquatic arthropods at high latitudes, (3) paleogeographic distribution and evolution of vertebrates and invertebrates as recorded by trace and body fossils; and (3) response of landscapes to changes in climate.\u003cbr/\u003e\u003cbr/\u003eIn terms of broader impacts, this project will provide an outstanding introduction to field research for graduate and undergraduate students, and generate related opportunities for several undergraduates. It will also stimulate exchange of ideas among research and primarily undergraduate institutions. Novel outreach activities are also planned to convey Earth history to the general public, including a short film on the research process and products, and paintings by a professional scientific illustrator of Permo-Traissic landscapes and ecosystems.", "east": 161.72, "geometry": "POINT(160.51 -77.695)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.59, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e PALEOZOIC \u003e CARBONIFEROUS \u003e PENNSYLVANIAN; PHANEROZOIC \u003e PALEOZOIC \u003e PERMIAN; PHANEROZOIC \u003e MESOZOIC \u003e TRIASSIC", "persons": "Miller, Molly; Sidor, Christian; Isbell, John", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "Burke Museum; USAP-DC", "science_programs": "Allan Hills", "south": -78.8, "title": "Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "uid": "p0000207", "west": 159.3}, {"awards": "0538683 Lal, Devendra", "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": "Solar activity during the last millennium, estimated from cosmogenic in-situ C14 in South Pole and GISP2 ice cores", "datasets": [{"dataset_uid": "600058", "doi": "10.15784/600058", "keywords": "Antarctica; Carbon-14; Cosmos; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Solar Activity; South Pole", "people": "Lal, Devendra", "repository": "USAP-DC", "science_program": null, "title": "Solar activity during the last millennium, estimated from cosmogenic in-situ C14 in South Pole and GISP2 ice cores", "url": "https://www.usap-dc.org/view/dataset/600058"}], "date_created": "Fri, 20 Feb 2009 00:00:00 GMT", "description": "0538683\u003cbr/\u003eLal\u003cbr/\u003eThis award supports a project to continue development of a new method for estimating solar activity in the past. It is based on measurements of the concentrations of in-situ produced C-14 in polar ice by cosmic rays, which depend only on (i) the cosmic ray flux, and (ii) ice accumulation rate. This is the only direct method available to date polar ice, since it does not involve any uncertain climatic transfer functions as are encountered in the applications of cosmogenic C-14 data in tree rings, or of Be-10 in ice and sediments. An important task is to improve on the temporal resolution during identified periods of high/low solar activity in the past 32 Kyr. The plan is to undertake a study of changes in the cosmic ray flux during the last millennium (1100-1825 A.D.), during which time 4 low and 1 high solar activity epoch has been identified from historical records. Sunspot data during most of these periods are sparse. Adequate ice samples are available from ice cores from the South Pole and from Summit, Greenland and a careful high resolution study of past solar activity levels during this period will be undertaken. The intellectual merit of the work includes providing independent verification of estimated solar activity levels from the two polar ice records of cosmic ray flux and greatly improve our understanding of solar-terrestrial relationships. \u003cbr/\u003eThe broader impacts include collaboration with other scientists who are experts in the application of the atmospheric cosmogenic C-14 and student training. Both undergraduates and a graduate student will be involved in the proposed research. Various forms of outreach will also be used to disseminate the results of this project, including public presentations and interactions with the media.", "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 Glaciology", "paleo_time": null, "persons": "Lal, Devendra", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Solar Activity during the Last Millennium, Estimated from Cosmogenic in-situ 14C in South Pole and GISP2 Ice Cores", "uid": "p0000555", "west": -180.0}, {"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": "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": "Young, Duncan A.; Blankenship, Donald D.; Bell, Robin; Buck, W. Roger", "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": "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": "Bell, Robin; Studinger, Michael S.", "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": "Bell, Robin; Studinger, Michael S.", "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": "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": "Studinger, Michael S.; Bell, Robin", "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": "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": "Bell, Robin; Studinger, Michael S.", "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": "Dalziel, Ian W.; Morse, David L.; Blankenship, Donald D.; Holt, John W.", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Aerogeophysics Data", "url": "https://www.usap-dc.org/view/dataset/609240"}, {"dataset_uid": "609336", "doi": "10.7265/N5CN71VX", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Subglacial Lake", "people": "Holt, John W.; Carter, Sasha P.; Blankenship, Donald D.", "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 Blankenship 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\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. 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. - 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. - 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. - 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. - 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. - 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. - SOAR will repair and/or refurbish equipment that was used during the 2000/01 field campaign. 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.", "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 Glaciology; Antarctic Earth Sciences; 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": "0124049 Berger, Glenn", "bounds_geometry": "POLYGON((161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.20000000000002 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163.20000000000002 -77.5,163.4 -77.5,163.4 -77.52,163.4 -77.54,163.4 -77.56,163.4 -77.58,163.4 -77.6,163.4 -77.62,163.4 -77.64,163.4 -77.66,163.4 -77.68,163.4 -77.7,163.20000000000002 -77.7,163 -77.7,162.8 -77.7,162.6 -77.7,162.4 -77.7,162.20000000000002 -77.7,162 -77.7,161.8 -77.7,161.6 -77.7,161.4 -77.7,161.4 -77.68,161.4 -77.66,161.4 -77.64,161.4 -77.62,161.4 -77.6,161.4 -77.58,161.4 -77.56,161.4 -77.54,161.4 -77.52,161.4 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 25 Aug 2008 00:00:00 GMT", "description": "0124049\u003cbr/\u003eBerger\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the Dry Valleys of the McMurdo Sound region of Antarctica. Using a modified Livingstone corer, transects of long cores will be obtained from Lakes Fryxell, Bonney, Joyce, and Vanda. A multiparameter approach will be employed which is designed to extract the greatest possible amount of former water-level, glaciological, and paleoenvironmental data from Dry Valleys lakes. Estimates of hydrologic changes will come from different proxies, including grain size, stratigraphy, evaporite mineralogy, stable isotope and trace element chemistry, and diatom assemblage analysis. The chronology, necessary to integrate the cores with the geomorphological record, as well as for comparisons with Antarctic ice-core and glacial records, will come from Uranium-Thorium, Uranium-Helium, and Carbon-14 dating of carbonates, as well as luminescence sediment dating. Evaluation of the link between lake-level and climate will come from hydrological and energy-balance modelling. Combination of the more continuous lake-core sequences with the spatially extensive geomorphological record will result in an integrated Antarctic lake-level and paleoclimate dataset that extends back at least 30,000 years. This record will be compared to Dry Valleys glacier records and to the Antarctic ice cores to address questions of regional climate variability, and then to other Southern Hemisphere and Northern Hemisphere records to assess interhemispheric synchrony or asynchrony of climate change.", "east": 163.4, "geometry": "POINT(162.4 -77.6)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LASERS", "is_usap_dc": false, "keywords": "Stratigraphy; Climate Variability; Shoreline Deposits; Dry Valleys; Antarctic Lake-level; Luminescence Geochronology; Grain Size; Paleoclimate; Antarctica; LABORATORY; Lake Cores", "locations": "Dry Valleys; Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Berger, Glenn; Hall, Brenda; Doran, Peter", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -77.7, "title": "Collaborative Research: Millennial Scale Fluctuations of Dry Valleys Lakes: Implications for Regional Climate Variability and the Interhemispheric (a)Synchrony of Climate Change", "uid": "p0000219", "west": 161.4}, {"awards": "0230448 Severinghaus, Jeffrey; 0230260 Bender, Michael", "bounds_geometry": "POLYGON((-75.34 86.6,-68.742 86.6,-62.144 86.6,-55.546 86.6,-48.948 86.6,-42.35 86.6,-35.752 86.6,-29.154 86.6,-22.556 86.6,-15.958 86.6,-9.36 86.6,-9.36 83.618,-9.36 80.636,-9.36 77.654,-9.36 74.672,-9.36 71.69,-9.36 68.708,-9.36 65.726,-9.36 62.744,-9.36 59.762,-9.36 56.78,-15.958 56.78,-22.556 56.78,-29.154 56.78,-35.752 56.78,-42.35 56.78,-48.948 56.78,-55.546 56.78,-62.144 56.78,-68.742 56.78,-75.34 56.78,-75.34 59.762,-75.34 62.744,-75.34 65.726,-75.34 68.708,-75.34 71.69,-75.34 74.672,-75.34 77.654,-75.34 80.636,-75.34 83.618,-75.34 86.6))", "dataset_titles": "Firn Air Inert Gas and Oxygen Observations from Siple Dome, 1996, and the South Pole, 2001; Trapped Gas Composition and Chronology of the Vostok Ice Core", "datasets": [{"dataset_uid": "609311", "doi": "10.7265/N5P26W12", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Lake Vostok; Paleoclimate; Vostok; Vostok Ice Core", "people": "Bender, Michael; Suwa, Makoto", "repository": "USAP-DC", "science_program": null, "title": "Trapped Gas Composition and Chronology of the Vostok Ice Core", "url": "https://www.usap-dc.org/view/dataset/609311"}, {"dataset_uid": "609290", "doi": "10.7265/N5FJ2DQC", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciology; Paleoclimate; Siple Dome; Snow/ice; Snow/Ice; South Pole", "people": "Battle, Mark; Severinghaus, Jeffrey P.; Bender, Michael", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Firn Air Inert Gas and Oxygen Observations from Siple Dome, 1996, and the South Pole, 2001", "url": "https://www.usap-dc.org/view/dataset/609290"}], "date_created": "Wed, 18 Jan 2006 00:00:00 GMT", "description": "High latitude deep ice cores contain fundamental records of polar temperatures, atmospheric dust loads (and continental aridity), greenhouse gas concentrations, the status of the biosphere, and other essential properties of past environments. An accurate chronology for these records is needed if their significance is to be fully realized. The dating challenge has stimulated efforts at orbital tuning. In this approach, one varies a timescale, within allowable limits, to optimize the match between a paleoenvironmental property and a curve of insolation through time. The ideal property would vary with time due to direct insolation forcing. It would be unaffected by complex climate feedbacks and teleconnections, and it would give a clean record with high signal/noise ratio. It is argued strongly that the O2/N2 ratio of ice core trapped gases is such a property, and evidence is presented that this property, whose atmospheric ratio is nearly constant, is tied to local summertime insolation. This award will support a project to analyze the O2/N2 ratios at 1 kyr intervals from ~ 115-400 ka in the Vostok ice core. Ancillary measurements will be made of Ar/N2, and Ne/N2 and heavy noble gas ratios, in order to understand bubble close-off fractionation and its manifestation in the Vostok trapped gas record. O2/N2 variations will be matched with summertime insolation at Vostok to achieve a high-accuracy chronology for the Vostok core. The Vostok and other correlatable climate records will then be reexamined to improve our understanding of the dynamics of Pleistocene climate change.", "east": 106.8, "geometry": "POINT(106.8 -72.4667)", "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 SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Paleoclimate; Siple Dome; Ice Age; Shallow Firn Air; Firn Air Isotope Measurements; Polar Firn Air; Ice Sample Gas Integrity; Oxygen Isotope; Noble Gas; Ice Core Gas Records; Atmospheric Gases; Trapped Gases; Not provided; LABORATORY; Vostok; Firn Air Isotopes; Thermal Fractionation; Ice Core Chemistry; Trapped Air Bubbles; Ice Core; Antarctica; South Pole; Ice Core Data; GROUND-BASED OBSERVATIONS; Gas Age; Firn Isotopes", "locations": "Antarctica; Vostok; Siple Dome; South Pole", "north": -72.4667, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Battle, Mark; Bender, Michael; Suwa, Makoto; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -72.4667, "title": "Collaborative Research: Trapped Gas Composition and the Chronology of the Vostok Ice Core", "uid": "p0000257", "west": 106.8}, {"awards": "9615554 Fitzpatrick, Joan", "bounds_geometry": null, "dataset_titles": "Digital Images of Thin Sections from Siple Dome; Digital Imaging for Siple Dome Ice Core Analysis, Antarctica", "datasets": [{"dataset_uid": "609127", "doi": "10.7265/N59Z92T4", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Photo/video; Photo/Video; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Fitzpatrick, Joan", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Digital Images of Thin Sections from Siple Dome", "url": "https://www.usap-dc.org/view/dataset/609127"}, {"dataset_uid": "609413", "doi": "10.7265/N5XG9P2G", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Photo/video; Photo/Video; Siple Dome; Siple Dome Ice Core", "people": "Fitzpatrick, Joan; Alley, Richard; Spencer, Matthew", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Digital Imaging for Siple Dome Ice Core Analysis, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609413"}], "date_created": "Wed, 14 May 2003 00:00:00 GMT", "description": "This award is for support for two years to develop the technology and methodology for digitizing the photographs and analyzing the thin sections from ice cores. In addition, the application of digital technology for whole-core stratigraphy, using digital photography, image enhancement and image processing will be investigated. The thin section analysis will be piloted with samples already in hand from the Taylor Dome ice core. If successful, these techniques will be applied to samples from the Siple Dome ice core, in cooperation with Principal Investigators already funded to retrieve and examine these sections. The original digital images with all original data annotation files will be distributed to Siple Dome principal investigators for their use in the interpretation of their own data. All software and hardware acquired for this project will become part of the permanent equipment inventory at the U.S. National Ice Core Laboratory and will be available for use by clients at the facility.", "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 CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Antarctica; Glaciology; Ice Sheet; Siple; Ice Core; Stratigraphy; GROUND STATIONS; Siple Dome; WAISCORES; Trapped Air Bubbles; Photo; Snow; Density; Volcanic Deposits; Not provided; Ice Core Data; GROUND-BASED OBSERVATIONS; Siple Coast; Chemical Composition", "locations": "Siple Dome; Antarctica; Siple; Siple Coast", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fitzpatrick, Joan; Alley, Richard; Spencer, Matthew", "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": "Digital Imaging for Ice Core Analysis", "uid": "p0000011", "west": null}, {"awards": "9527262 Gow, Anthony", "bounds_geometry": null, "dataset_titles": "Physical and Structural Properties of the Siple Dome Ice Cores", "datasets": [{"dataset_uid": "609128", "doi": "10.7265/N5668B34", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Photo/video; Photo/Video; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Meese, Deb; Gow, Tony", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Physical and Structural Properties of the Siple Dome Ice Cores", "url": "https://www.usap-dc.org/view/dataset/609128"}], "date_created": "Wed, 14 May 2003 00:00:00 GMT", "description": "This award is for support for a program to investigate the visual stratigraphy, index physical properties, relaxation characteristics and crystalline structure of ice cores from Siple Dome, West Antarctica. This investigation will include measurements of a time-priority nature that must be initiated at the drill site on freshly-drilled cores. This will be especially true of cores from the brittle ice zone, which is expected to comprise a significant fraction of the ice core. The brittle zone includes ice in which relaxation , resulting from the release of confining pressure is maximized and leads to significant changes in the mechanical condition of the core that must be considered in relation to the processing and analysis of ice samples for entrapped gas and chemical studies. This relaxation will be monitored via precision density measurements made initially at the drill site and repeated at intervals back in the U.S. Other studies will include measurement of the annual layering in the core to as great a depth as visual stratigraphy can be deciphered, crystal size measurements as a function of depth and age, c-axis fabric studies, and analysis of the physical properties of any debris-bearing basal ice and its relationship to the underlying bedrock. Only through careful documentation and analysis of these key properties can we hope to accurately assess the dynamic state of the ice and the age-depth relationships essential to deciphering the paleoclimate record at this location.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Siple Dome; Antarctica; Stratigraphy; Ice Sheet; GROUND-BASED OBSERVATIONS; Density; Siple; Chemical Composition; Volcanic Deposits; Siple Coast; WAISCORES; Not provided; GROUND STATIONS; Pico; Ice Core; Tephra; Fabric; Glaciology; Snow", "locations": "Antarctica; Siple; Siple Coast; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Gow, Tony; Meese, Deb", "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": "Physical and Structural Properties of the Siple Dome Core", "uid": "p0000064", "west": null}, {"awards": "9316715 Taylor, Susan", "bounds_geometry": null, "dataset_titles": "Micrometeorites from the South Pole Water Well", "datasets": [{"dataset_uid": "609113", "doi": "10.7265/N5R49NQK", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Cosmos; Geochemistry; Meteorite; Scanning Electron Microscope (SEM) Images; South Pole", "people": "Taylor, Susan", "repository": "USAP-DC", "science_program": null, "title": "Micrometeorites from the South Pole Water Well", "url": "https://www.usap-dc.org/view/dataset/609113"}], "date_created": "Tue, 01 Jan 2002 00:00:00 GMT", "description": "9316715 Taylor This award is for support to collect micrometeorites from the bottom of the new water well at South Pole Station, Antarctica. The large volume of firn and ice being melted provides the concentrating mechanism needed to collect large numbers of micrometeorites that occur in low concentrations in the ice. The first task of the project is to design a collection system to retrieve the micrometeorites from the bottom of the water well. The collector must be reliable, easy to operate, must collect all particles larger than 10 mm and should not contaminate the well\u0027s water quality. Following successful design and deployment of the collector, recovered particles will be catalogued and distributed to interested researchers. ***", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e ELECTRON MICROPROBES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e SCANNING ELECTRON MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e GRABBERS/TRAPS/COLLECTORS \u003e SEDIMENT TRAPS", "is_usap_dc": true, "keywords": "USAP-DC; Micrometeorites; SEM/EMAX; GROUND-BASED OBSERVATIONS; South Pole Water Well; Glass Spherules", "locations": "South Pole Water Well", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Taylor, Susan", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Retrieval and Analysis of Extraterrestrial Particles from the Water Well at the South Pole Station, Antarctica", "uid": "p0000057", "west": null}, {"awards": "9316338 Jacobel, Robert", "bounds_geometry": null, "dataset_titles": "Siple Dome Glaciology and Ice Stream History 1994, 1996", "datasets": [{"dataset_uid": "609085", "doi": "10.7265/N5Z31WJQ", "keywords": "Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Sample/collection Description; Sample/Collection Description; Siple Dome; Siple Dome Ice Core", "people": "Jacobel, Robert", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Glaciology and Ice Stream History 1994, 1996", "url": "https://www.usap-dc.org/view/dataset/609085"}], "date_created": "Fri, 01 Jan 1999 00:00:00 GMT", "description": "9316338 Jacobel This award is for support for a program of glaciological studies of Siple Dome and its surroundings between Ice Streams C and D. The purpose of the work is to characterize the dynamic environment and ice stratigraphy to aid in the assessment of Siple Dome as a potential deep ice core site, and to determine whether the configuration of ice stream flow in the region was different in the past than now. The work involves measurements of the configuration and continuity of internal layers in the ice, using radar echo sounding and determination of velocity field, based on standard GPS surveying. The goals of the work are relevant to understanding the dynamics of the West Antarctic Ice Sheet (WAIS), its past history and its potential future behavior, including possible effects on global sea level. This work is a collaborative project between the University of Washington, the University of Colorado and St. Olaf College. ***", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR", "is_usap_dc": true, "keywords": "Siple Dome; Antarctic; Glaciology; Radar; GROUND-BASED OBSERVATIONS; Ice Stream", "locations": "Antarctic; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Jacobel, Robert", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Siple Dome Glaciology and Ice Stream History", "uid": "p0000190", "west": null}]
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Project Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Dataset Links and Repositories | Abstract | Bounds Geometry | Geometry | Selected | Visible | |||||||||||||
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Collaborative Research: ANT LIA: Diving into the Ecology of an Antarctic Ascidian-Microbiome-Palmerolide Association using a Multi-omic and Functional Approach
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2142914 2142912 2142913 |
2024-10-17 | Baker, Bill; Murray, Alison; Tresguerres, Martin | No dataset link provided | Non-technical description 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. Technical description 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. 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. | 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)) | POINT(-130 -70) | false | false | |||||||||||||
Fe Behavior and Bioavailability in Sub-aerial Runoff into the Ross Sea
|
1841228 |
2024-10-16 | Lyons, W. Berry; Gardner, Christopher B. | 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. 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. 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. | 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)) | POINT(163.4642475 -77.5853675) | false | false | ||||||||||||||
ANT LIA: The Role of Sex Determination in the Radiation of Antarctic Notothenioid Fish
|
2232891 |
2023-08-14 | Postlethwait, John; Desvignes, Thomas | No dataset link provided | Antarctic animals face tremendous threats as Antarctic ice sheets melt and temperatures rise. About 34 million years ago, when Antarctica began to cool, most species of fish became locally extinct. A group called the notothenioids, however, survived due to the evolution of antifreeze. The group eventually split into over 120 species. Why did this group of Antarctic fishes evolve into so many species? One possible reason why a single population splits into two species relates to sex genes and sex chromosomes. Diverging species often have either different sex determining genes (genes that specify whether an individual’s gonads become ovaries or testes) or have different sex chromosomes (chromosomes that differ between males and females within a species, like the human X and Y chromosomes). We know the sex chromosomes of only a few notothenioid species and know the genetic basis for sex determination in none of them. The aims of this research are to: 1) identify sex chromosomes in species representing every major group of Antarctic notothenioid fish; 2) discover possible sex determining genes in every major group of Antarctic notothenioid fish; and 3) find sex chromosomes and possible sex determining genes in two groups of temperate, warmer water, notothenioid fish. These warmer water fish include groups that never experienced the frigid Southern Ocean and groups that had ancestors inhabiting Antarctic oceans that later adjusted to warmer waters. This project will help explain the mechanisms that led to the division of a group of species threatened by climate change. This information is critical to conserve declining populations of Antarctic notothenioids, which are major food sources for other Antarctic species such as bird and seals. The project will offer a diverse group of undergraduates the opportunity to develop a permanent exhibit at the Eugene Science Center Museum. The exhibit will describe the Antarctic environment and explain its rapid climate change. It will also introduce the continent’s bizarre fishes that live below the freezing point of water. The project will collaborate with the university’s Science and Comics Initiative and students in the English Department’s Comics Studies Minor to prepare short graphic novels explaining Antarctic biogeography, icefish specialties, and the science of this project as it develops. As Antarctica cooled, most species disappeared from the continent’s waters, but cryonotothenioid fish radiated into a species flock. What facilitated this radiation? Coyne’s “two rules of speciation” offer explanations for why species diverge: 1) the dysgenic sex in an interspecies hybrid is the one with two different sex chromosomes (i.e., in humans, it would be XY males and not XX females); and 2) “sex chromosomes play an outsized role in speciation”. These ideas propel the project’s main hypothesis: new sex chromosomes and new sex determination genes associate with cryonotothenioid speciation events. The main objective of the research is to identify notothenioid sex chromosomes and candidate sex-determination genes in many notothenioid species. The project’s first aim is to identify Antarctic fish sex chromosomes, asking the question: Did new sex chromosomes accompany speciation events? Knowledge gaps include: which species have cryptic sex chromosomes; which have newly evolved sex chromosomes; and which are chromosomally XX/XY or ZZ/ZW. Methods involve population genomics (RAD-seq and Pool-seq) for more than 20 Antarctic cryonotothenioids. The prediction is frequent turnover of sex chromosomes. The project’s second aim is to Identify candidate Antarctic cryonotothenioid sex-determination genes, asking the question: Did new sex-determination genes accompany Antarctic cryonotothenioid speciation events? A knowledge gap is the identity of sex determination genes in any notothenioid. Preliminary data show that three sex-linked loci are in or adjacent to three different candidate sex determination genes: 1) a duplicate of bmpr1ba in blackfin icefish; 2) a tandem duplicate of gsdf in South Georgia icefish; and 3) a transposed duplicate of gsdf in striped notothen. Methods involve annotating the genomic neighborhoods of cryonotothenioid sex linked loci for anomalies in candidate sex genes, sequencing sex chromosomes, and testing sex gene variants by CRISPR mutagenesis in zebrafish. The prediction is frequent turnover of sex determination genes. The project’s third aim is to identify sex chromosomes and sex-determination genes in temperate notothenioids. Basally diverging temperate notothenioids (‘basals’) lack identifiable sex chromosomes, consistent with temperature-cued sex determination, and one ‘basal’ species is a hermaphrodite. The constantly cold Southern Ocean rules out temperature, a common sex determination cue in many temperate fish, favoring genetic sex determination. Some cryonotothenioids re-invaded temperate waters (‘returnees’). Knowledge gaps include whether basals and returnees have strong sex determination genes. Methods employ pool-seq. The prediction is that genetic sex determination is weak in basals and that returnees have the same, but weaker, sex-linked loci as their Antarctic sister clade. A permanent exhibit will be established at the Eugene Science Center Museum tentatively entitled: The Antarctic: its fishes and climate change. Thousands of visitors, especially school children will be exposed, to the science of Antarctic ecosystems and the impacts of climate change. The research team will collaborate with the university’s Science and Comics Initiative to produce short graphic novels explaining Antarctic biogeography, icefish specialties, and this project. 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. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
RAPID: In-situ Observations to Characterize Multi-Scale Turbulent Atmospheric Processes Impacting Climate at Southern High Latitudes
|
2326960 |
2023-05-20 | Doddi, Abhiram; Lawrence, Dale | No dataset link provided | This international collaboration between the University of Colorado, the University of Kyoto, and the National Institute of Polar Research in Tokyo, will investigate the sources of atmospheric turbulence in coastal Antarctica. Strong winds forced against terrain produce waves called atmospheric gravity waves, which can grow in amplitude as they propagate to higher altitudes, becoming unstable, breaking, and causing turbulence. Another source of turbulence is shear layers in the atmosphere, where one layer of air slides over another, resulting in Kelvin-Helmholtz Instabilities. Collectively, both play important roles in accurately representing the Antarctic climate in weather prediction models. Collecting new turbulence observations in these remote southern high latitudes will improve wind and temperature forecasts of the Antarctic climate. This project will observe gravity wave and shear-induced turbulence dynamics by deploying custom high-altitude balloon systems in coordination and collaboration with a powerful remote sensing radar and multiple long-duration balloons during an observational field campaign at the Japanese Antarctic Syowa station. This research is motivated by the fact that the sources representing realistic multi-scale gravity wave (GW) drag, and Kelvin-Helmholtz Instability (KHI) dynamics, along with their contributions to momentum and energy budgets due to turbulent transport/mixing, are largely missing in the current General Circulation Model (GCM) parameterization schemes, resulting in degraded synoptic-scale forecasts at southern high latitudes. This project utilizes high-resolution in-situ turbulence instruments to characterize the large-scale dynamics of 1) orographic GWs produced by katabatic forcing, 2) non-orographic GWs produced by low-pressure synoptic-scale events, and 3) KHI instabilities emerging in a wide range of scales and background environments in the coastal Antarctic region. The project will deploy dozens of low-cost balloon systems equipped with custom in-situ turbulence and radiosonde instruments at the Japanese Syowa station in Eastern Antarctica. Balloon payloads descend slowly from an apogee of 20 km to provide high- resolution, wake-free turbulence observations, with deployment guidance from the PANSY radar at Syowa, in coordination with the LODEWAVE long duration balloon experiment. The combination of in-situ and remote sensing turbulence observations will quantify the structure and dynamics of small-scale turbulent atmospheric processes associated with GWs and KHI, thought to be ubiquitous in polar environments but rarely observed. Momentum fluxes and turbulence dissipation rates measured over a wide range of scales and background environments will provide datasets to validate current GCM parameterizations for atmospheric GW drag and turbulence diffusion coefficients in the lower and middle atmospheres at southern high latitudes, increasing our understanding of these processes and their contribution to Antarctic circulation and climate. 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. | POLYGON((36 -68,36.9 -68,37.8 -68,38.7 -68,39.6 -68,40.5 -68,41.4 -68,42.3 -68,43.2 -68,44.1 -68,45 -68,45 -68.2,45 -68.4,45 -68.6,45 -68.8,45 -69,45 -69.2,45 -69.4,45 -69.6,45 -69.8,45 -70,44.1 -70,43.2 -70,42.3 -70,41.4 -70,40.5 -70,39.6 -70,38.7 -70,37.8 -70,36.9 -70,36 -70,36 -69.8,36 -69.6,36 -69.4,36 -69.2,36 -69,36 -68.8,36 -68.6,36 -68.4,36 -68.2,36 -68)) | POINT(40.5 -69) | false | false | |||||||||||||
Collaborative Research: Understanding the Massive Phytoplankton Blooms over the Australian-Antarctic Ridge
|
2135185 2135184 2135186 |
2022-09-30 | Arrigo, Kevin; Thomas, Leif N; Baumberger, Tamara; Resing, Joseph | No dataset link provided | Phytoplankton blooms throughout the world’s oceans support critical marine ecosystems and help remove carbon dioxide (CO2) from the atmosphere. Traditionally, it has been assumed that phytoplankton blooms in the Southern Ocean are stimulated by iron from either nearby land 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 carbon in the deep ocean. Our proposed work will uncover the importance of hydrothermal activity in stimulating a large phytoplankton bloom 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 carbon cycle in the Southern Ocean, which appears to trigger local hotspots of biological activity which are a potential 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 PhD 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. 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 sea surface height (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. 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. | 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)) | POINT(162.5 -62) | false | false | |||||||||||||
OPP-PRF: Conjugate Experiment to Explore Magnetospheric Phenomena Via Spatial Sonification and Mixed Reality
|
2218996 |
2022-08-07 | Collins, Kristina | No dataset link provided | Magnetic field variations on the Earth’s surface can be used to remote sense and characterize electrical currents and plasma waves in the near-Earth space environment that can affect technology, for example by inducing currents in power grids. Asymmetries between the space environment in the polar regions of the northern and southern hemispheres can profoundly affect these magnetic field variations. Magnetometers, which measure the strength and direction of magnetic fields, have been installed in the Arctic and Antarctic at opposite ends of the Earth’s magnetic field lines. By looking at data from both sets of magnetometers, researchers can determine whether disturbances in the Earth’s magnetosphere (a region of near-Earth space dominated by the Earth’s magnetic field) caused by the Sun impact the Northern hemisphere, the Southern hemisphere or both, and thus understand the sources of north-south hemisphere asymmetries. Some events that appear in the magnetometer data may be difficult for computers to identify, but easy for people to identify if the data is translated into sound. Researchers will develop a tool for listening to data in a virtual reality environment, so that data from various instruments can be played back, making it easier to explore datasets intuitively. This system will be prototyped using a mixed reality headset for use in both science and education and may be used to analyze data taken at the same time by sensors on the ground and on satellites. This project will examine one particular type of disturbance – magnetosheath jets – and its relation to plasma waves by addressing the question “Do magnetosheath jets routinely drive Pc5/Pc6 geomagnetic pulsations?” via the analysis of magnetometer data from geomagnetically conjugate (based on the International Geomagnetic Reference Field, IGRF) Arctic and Antarctic magnetometers. This question will be approached first through traditional plotting and visual analysis, then by presenting datastreams as sound sources situated in a virtual audio environment developed in the Unity game engine and integrated with mixed reality presentation via the Microsoft Hololens platform. This approach will leverage human capabilities for spatial discrimination of sounds to identify geomagnetic pulsations (surface magnetic field variations related to plasma waves in outer space) related to magnetosheath jet events with potentially large north-south hemispheric asymmetries, spatially localized wave activity, and irregular waveforms. The resulting presentation modality will make use of existing repositories of magnetometer data and may potentially be extended to the presentation of synchronous datasets from multiple sensing networks. 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. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Collaborative Research: Diversity and ecological impacts of Antarctic mixotrophic phytoplankton
|
1744767 |
2022-07-27 | Sanders, Robert; Gast, Rebecca; Jeffrey, Wade H. | 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: 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. | 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)) | POINT(-65 -66.5) | false | false | ||||||||||||||
Collaborative Research: Modeling ice-ocean interaction for the rapidly evolving ice shelf cavities of Pine Island and Thwaites glaciers, Antarctica
|
1643285 1643174 |
2022-05-13 | Joughin, Ian; Dutrieux, Pierre; Padman, Laurence; Springer, Scott |
|
The West Antarctic Ice Sheet contains enough ice to raise global sea levels by 3-4 meters. Ice-sheet volume falls, and sea level increases, when more ice is lost to the ocean by glacier flow than is replaced by snowfall. Glacier speed is reduced when ice shelves, which are the floating extensions of the ice sheets, are present. Processes that affect ice shelf thickness and extent therefore influence the rates of grounded ice loss and sea-level rise. West Antarctica is currently losing ice, at an accelerating rate, with most loss occurring in the Amundsen Sea region via discharge from Pine Island and Thwaites glaciers. This loss was initiated by increased circulation of relatively warm ocean water beneath these glacier's ice shelves, causing them to thin by melting. However, this melting also depends on how the changing shape of the ice shelves affects the ocean circulation beneath them and the speeds of the grounded glaciers upstream. Limited understanding of these processes leads to uncertainties in estimates of future ice loss. This interdisciplinary project brings together glaciologists and oceanographers from three US institutions to study the interactions between changing glacier flow, ice shelf shape and extent, and ocean circulation. Data and numerical models will be used to identify the key processes that determine how rapidly this region can shed ice. The project team will train postdocs and graduate students in cutting-edge modeling techniques, and educate the public about Antarctic ice loss through talks, school science fairs, and Seattle Science Center's annual Polar Science Weekend. The project team will conduct simulations, using a combination of ice-sheet and ocean models, to reduce uncertainties in projected ice loss from Pine Island and Thwaites glaciers by: (i) assessing how ice-shelf melt rates will change as the ice-shelf cavities evolve through melting and grounding-line retreat, and (ii) improving understanding of the sensitivity of sub-shelf melt rates to changes in ocean state on the nearby continental shelf. These studies will reduce uncertainty on ice loss and sea-level rise estimates, and lay the groundwork for development of future fully-coupled ice-sheet/ocean models. The project will first develop high-resolution ice-shelf-cavity circulation models driven by modern observed regional ocean state and validated with estimates of melt derived from satellite observations. Next, an ice-flow model will be used to estimate the future grounding retreat. An iterative process with the ocean-circulation and ice-flow models will then simulate melt rates at each stage of retreat. These results will help assess the validity of the hypothesis that unstable collapse of the Amundsen Sea sector of West Antarctica is underway, which was based on simplified models of melt rate. These models will also provide a better understanding of the sensitivity of melt to regional forcing such as changes in Circumpolar Deep Water temperature and wind-driven changes in thermocline height. Finally, several semi-coupled ice-ocean simulations will help determine the influence of the ocean-circulation driven melt over the next several decades. These simulations will provide a much-improved understanding of the linkages between far-field ocean forcing, cavity circulation and melting, and ice-sheet response. | POLYGON((-104 -73,-102.2 -73,-100.4 -73,-98.6 -73,-96.8 -73,-95 -73,-93.2 -73,-91.4 -73,-89.6 -73,-87.8 -73,-86 -73,-86 -73.8,-86 -74.6,-86 -75.4,-86 -76.2,-86 -77,-86 -77.8,-86 -78.6,-86 -79.4,-86 -80.2,-86 -81,-87.8 -81,-89.6 -81,-91.4 -81,-93.2 -81,-95 -81,-96.8 -81,-98.6 -81,-100.4 -81,-102.2 -81,-104 -81,-104 -80.2,-104 -79.4,-104 -78.6,-104 -77.8,-104 -77,-104 -76.2,-104 -75.4,-104 -74.6,-104 -73.8,-104 -73)) | POINT(-95 -77) | false | false | |||||||||||||
Weddell Gyre Mean Circulation and Eddy Statistics from Floats
|
2148517 |
2022-03-25 | Hancock, Cathrine; Speer, Kevin |
|
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 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. | 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)) | POINT(-15 -65) | false | false | |||||||||||||
Integrating petrologic records and geodynamics: Quantifying the effects of glaciation on crustal stress and eruptive patterns at Mt. Waesche, Executive Committee Range, Antarctica
|
2122248 |
2021-08-19 | Waters, Laura; Naliboff, John; Zimmerer, Matthew | No dataset link provided | This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). The geologic record reveals that volcanic activity increases when glaciers retreat and major ice sheets thin. This relationship produces a positive feedback mechanism where the uptick in volcanism increases greenhouse gasses concentrations, leading to climate warming and further deglaciation. Although the pattern between volcanism and deglaciation is observed in the geologic record, the exact mechanism(s) by which glaciers impact a volcanic plumbing system is unknown. This project focuses on Mount Waesche, a volcano in West Antarctica, that frequently erupts during warm, interglacial periods and undergoes a period of less activity during cold, glacial periods. This project will examine compositions of the rocks and minerals from Mount Waesche to determine magma storage depths, allowing the investigators to understand how magma plumbing systems change in response to glacial cycles. These results will be compared with geodynamic simulations to understand the physics behind the effects of deglaciation on the magmatic plumbing systems within Earth’s crust. The investigators will additionally partner with Mentoring Kids Works to develop several Polar and Earth Science Educational Modules aimed at improving reading skills in third grade students in New Mexico. The proposed Polar and Earth Science program consists of modules that include readings of books introducing students to Earth and Polar science themes, paired with Earth and Polar Science activities, followed by simple experiments, where students make predictions and collect data. Information required to implement our Polar and Earth Science curriculum will be made available online. Isotopic and sedimentary datasets reveal that volcanic activity typically increases during interglacial periods. However, the physical mechanisms through which changes in the surface loading affect volcanic magmatic plumbing systems remain unconstrained. Recently generated 40Ar/39Ar eruption ages indicate that 86% of the dated samples from Mt. Waesche, a late Quaternary volcano in Marie Byrd land, correlate with interglacial periods, suggesting this volcano uniquely responds to changes in the West Antarctic Ice Sheet. We propose to combine the petrology of Mount Waesche’s volcanic record, constraints on changing ice loads through time, and geodynamic modelling to: (1) Determine how pre-eruptive storage conditions change during glacial and interglacial periods using whole rock and mineral compositions of volcanic rocks; (2) Conduct geodynamic modeling to elucidate the relationship between lithospheric structure, temporal variations in ice sheet thickness, and subsequent changes in crustal stresses and magmatic transport and, therefore, the mechanism(s) by which deglaciation impacts magmatic plumbing systems; (3) Use the outcomes of objectives (1) and (2) to provide new constraints on the changes in ice sheet thickness through time that could plausibly trigger future volcanic and magmatic activity in West Antarctica. This collaborative approach will provide a novel methodology to determine prior magnitudes and rates of ice load changes within the Marie Byrd Land region of Antarctica. Lastly, estimates of WAIS elevation changes from this study will be compared to ongoing studies at Mount Waesche focused on constraining last interglacial ice sheet draw down using cosmogenic exposure ages obtained from shallow drilling. The scope of work also includes a partnership with Mentoring Kids Works to develop several Polar and Earth Science Educational Modules aimed at improving reading skills in third grade students in New Mexico. The proposed Polar and Earth Science program consists of modules that include readings of books introducing students to Earth and Polar science themes, paired with Earth and Polar Science activities, followed by simple experiments, where students make predictions and collect data. Information required to implement our Polar and Earth Science curriculum will be made available online. 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. | POLYGON((-127.143608 -77.1380528,-127.1012394 -77.1380528,-127.0588708 -77.1380528,-127.0165022 -77.1380528,-126.9741336 -77.1380528,-126.931765 -77.1380528,-126.8893964 -77.1380528,-126.8470278 -77.1380528,-126.8046592 -77.1380528,-126.7622906 -77.1380528,-126.719922 -77.1380528,-126.719922 -77.14809141,-126.719922 -77.15813002,-126.719922 -77.16816863,-126.719922 -77.17820724,-126.719922 -77.18824585,-126.719922 -77.19828446,-126.719922 -77.20832307,-126.719922 -77.21836168,-126.719922 -77.22840029,-126.719922 -77.2384389,-126.7622906 -77.2384389,-126.8046592 -77.2384389,-126.8470278 -77.2384389,-126.8893964 -77.2384389,-126.931765 -77.2384389,-126.9741336 -77.2384389,-127.0165022 -77.2384389,-127.0588708 -77.2384389,-127.1012394 -77.2384389,-127.143608 -77.2384389,-127.143608 -77.22840029,-127.143608 -77.21836168,-127.143608 -77.20832307,-127.143608 -77.19828446,-127.143608 -77.18824585,-127.143608 -77.17820724,-127.143608 -77.16816863,-127.143608 -77.15813002,-127.143608 -77.14809141,-127.143608 -77.1380528)) | POINT(-126.931765 -77.18824585) | false | false | |||||||||||||
EAGER: Origin and Physiological Consequences of a Neoplasm Outbreak in Antarctic Fish
|
1947040 |
2021-07-01 | Postlethwait, John; Varsani, Arvind; Desvignes, Thomas | Antarctica’s native animals face increasing stressors from warming oceans. A key unanswered question is how Antarctic life will respond. If warmer waters contribute to fish disease susceptibility, then iconic Antarctic predators they support, including penguins, seals, and killer whales, will suffer. A recent scientific cruise on the Antarctic peninsula encountered a population of crowned notothen fish that were plagued by pink, wart-like tumors that covered 10% to 30% of the body surface on about a third of the animals. Similar tumors had not previously been reported, suggesting that this might be a new disease that threatens Antarctic fish. The goal of proposed work is to identify the biological origins of the tumor and how it affects cell function and organismal physiology. The work is potentially transformative because it studies what might be a harbinger of Antarctic fish responses to global climate change. The project has several Broader Impacts. First, it will publicize the tumors. Because Antarctic researchers have never reported a tumor epidemic, the community must become aware of the outbreak and the tumor’s distinct diagnostic features. Second, dissemination of project results will stir further research to determine if this is an isolated event or is becoming a general phenomenon, and thus a broad concern for Antarctic ecosystems. Third, assays the project develops to detect the disease will enhance research infrastructure. Finally, work will broaden the nation’s scientific workforce by providing authentic research experiences for high school students and undergraduates from groups underrepresented in scientific research. The overall goal of proposed work is to identify the biological origins of the neoplasia and how it affects cell function and physiology. Aim 1 is to identify the pathogenic agent. Aim 1a is to test the hypothesis that a virus causes the neoplasia by isolating and sequencing viral nucleic acids from neoplasias and from animals that are not visibly affected. Aim 1b is to test neoplasias for bacteria, fungi, protozoa, or invertebrate parasites not present in healthy skin. Aim 2 is to learn how the disease alters the biology of affected cells. Aim 2a is to examine histological sections of affected and control tissues to see if the neoplasias are similar to previously reported skin diseases in temperate water fishes. Aim 2b is to examine the function of neoplastic cells by RNA-seq transcriptomics to identify genes that are differentially expressed in neoplasias and normal skin. Achieving these Aims will advance knowledge by identifying the causes and consequences of an outbreak of neoplasias in Antarctic fish. Proposed work is significant because it is the first to investigate a neoplasia cluster in Antarctic fish. 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. | POLYGON((-65.3 -63.3,-65 -63.3,-64.7 -63.3,-64.4 -63.3,-64.1 -63.3,-63.8 -63.3,-63.5 -63.3,-63.2 -63.3,-62.9 -63.3,-62.6 -63.3,-62.3 -63.3,-62.3 -63.47,-62.3 -63.64,-62.3 -63.81,-62.3 -63.98,-62.3 -64.15,-62.3 -64.32,-62.3 -64.49,-62.3 -64.66,-62.3 -64.83,-62.3 -65,-62.6 -65,-62.9 -65,-63.2 -65,-63.5 -65,-63.8 -65,-64.1 -65,-64.4 -65,-64.7 -65,-65 -65,-65.3 -65,-65.3 -64.83,-65.3 -64.66,-65.3 -64.49,-65.3 -64.32,-65.3 -64.15,-65.3 -63.98,-65.3 -63.81,-65.3 -63.64,-65.3 -63.47,-65.3 -63.3)) | POINT(-63.8 -64.15) | false | false | ||||||||||||||
Collaborative Research: Understanding the evolution of high-latitude Permo-Triassic paleoenvironments and their vertebrate communities
|
1341376 1341475 2001033 1341304 1341645 |
2021-06-29 | Sidor, Christian; Smith, Nathan; Makovicky, Peter; Tabor, Neil |
|
Around 252 million years ago, a major mass extinction wiped out upwards of 90% of species on Earth. Coincident with this extinction, the Antarctic portion of the supercontinent of Pangea transitioned to a warmer climatic regime and became devoid of glaciers. Little is known about the survivors of the extinction in Antarctica, although it has been hypothesized that the continent's high latitude location shielded it from the worst of the extinction's effects. The Shackleton Glacier region is the best place to study this extinction in Antarctica because it exposes an abundance of correct age rocks and relevant fossils were found there in the 1960s and 1980s. For this research, paleontologists will study fossil vertebrates that span from about 260 to 240 million years ago to understand how life evolved at high latitudes in the face of massive climate change. In addition, geologists will use fossil soils and fossil plant matter to more precisely reconstruct the climate of Antarctica across this extinction boundary. These data will allow for a more complete understanding of ancient climates and how Antarctic life compared to that at lower latitudes. Undergraduate and graduate students will be actively involved in this research. Public engagement in Antarctic science will be accomplished at several natural history museums. This three-year project will examine the evolution of Permo-Triassic paleoenvironments and their vertebrate communities by conducting fieldwork in the Shackleton Glacier region of Antarctica. The team will characterize the Permo-Triassic boundary within Shackleton area strata and correlate it to other stratigraphic successions in the region (e.g. via stable carbon isotope stratigraphy of fossilized plant organic matter). The researchers will use multiple types of data to assess the 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 (~70° S) tetrapod fauna of the entire Triassic and thus has the potential to shed important light on the evolution of polar life during the early Mesozoic. The biology of Triassic vertebrates from Antarctica will be compared to conspecifics from lower paleolatitudes through analysis of growth in bone and tusk histology. An interdisciplinary approach will be used 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. | 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)) | POINT(-177.5 -85.5) | false | false | |||||||||||||
Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems
|
1543344 |
2021-05-18 | Soreghan, Gerilyn; Elwood Madden, Megan |
|
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. | None | None | false | false | |||||||||||||
Collaborative Research: Elucidating Environmental Controls of Productivity in Polynas and the Western Antarctic Peninsula
|
1643652 1643618 |
2021-04-29 | van Dijken, Gert; Arrigo, Kevin; Dinniman, Michael; Hofmann, Eileen |
|
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. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Collaborative Research: Antarctic Airborne ElectroMagnetics (ANTAEM) - Revealing Subsurface Water in Coastal Antarctica
|
1644187 |
2020-09-13 | Tulaczyk, Slawek; Mikucki, Jill |
|
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. 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. | 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)) | POINT(164.75 -77.6) | false | false | |||||||||||||
Finding the Missing Geomagnetic Dipole Signal in Global Pleointensity Data: Revisiting the High Southerly Latitudes
|
1541285 |
2020-08-24 | Tauxe, Lisa; Staudigel, Hubertus |
|
The geomagnetic field is decreasing rapidly, leading some to propose that it will undergo collapse followed by a return to its usual strength but in the opposite direction, a phenomenon known as a "polarity reversal" which happened last approximately 800,000 years ago. Such a collapse would have a potentially devastating effect on the ability of the magnetic field to shield us from cosmic ray bombardment, placing our electrical grid at grave risk, among other things. The probability of such a drastic event happening depends on the average strength of the magnetic field. If the average is approximately equal to the present field (as many researchers assume), then the fact that the field is dropping rapidly would be more alarming than if the magnetic field is quite a bit higher than average, as implied by the current data for the ancient magnetic field from Antarctica. The argument over the average field strength stems from the difficulty of its estimation. The new approach advocated for in this proposal will allow researchers to obtain a robust data set for high southerly latitudes which will greatly enhance confidence in estimates of the average ancient field strength, contributing to our ability to assess the likelihood of catastrophic collapse of the geomagnetic field. The difficulty in estimating the average magnetic field strength over the past five million years is apparent when one examines data for ancient field strength as a function of latitude. Directions of the geomagnetic field have been well approximated by an axial dipole (bar magnetic) at the center of the Earth that is aligned with the spin axis. But the signal of such an axial geomagnetic dipole, whereby the field strength doubles from the equator to the poles, is not readily apparent in the database of field strength estimates from the last five million years. There are several possible explanations for this troubling failure: 1) combining data from different ages with possibly different average intensities leads to an inappropriate comparison of field states, 2) there is a depression of field strength at high latitude, perhaps reflecting the role of the `tangent cylinder?, or 3) there is noise and/or bias introduced by poor selection criteria or poor experimental design. The latter is a likely explanation as published data from the 1960 lava flow on Hawaii display the entire range of intensity values observed on the Earth's surface today, yet samples from this lava flow should all have one distinct value. This proposal benefits from the development of new experimental methods, better field strategies and a new approach to data selection that will allow accurate estimation of the ancient field strength through a comprehensive field campaign to collect lava flow samples from previously studied outcrops targeting the most promising material. These will be analyzed using the most robust experimental protocol and subjected to rigorous selection criteria proven to reject inaccurate results, leading to both accurate and precise estimates of ancient field strength. | POLYGON((162.144 -77.2233,162.8676 -77.2233,163.5912 -77.2233,164.3148 -77.2233,165.0384 -77.2233,165.762 -77.2233,166.4856 -77.2233,167.2092 -77.2233,167.9328 -77.2233,168.6564 -77.2233,169.38 -77.2233,169.38 -77.34097,169.38 -77.45864,169.38 -77.57631,169.38 -77.69398,169.38 -77.81165,169.38 -77.92932,169.38 -78.04699,169.38 -78.16466,169.38 -78.28233,169.38 -78.4,168.6564 -78.4,167.9328 -78.4,167.2092 -78.4,166.4856 -78.4,165.762 -78.4,165.0384 -78.4,164.3148 -78.4,163.5912 -78.4,162.8676 -78.4,162.144 -78.4,162.144 -78.28233,162.144 -78.16466,162.144 -78.04699,162.144 -77.92932,162.144 -77.81165,162.144 -77.69398,162.144 -77.57631,162.144 -77.45864,162.144 -77.34097,162.144 -77.2233)) | POINT(165.762 -77.81165) | false | false | |||||||||||||
Microbial Community Structure and Expression of Functional Genes Involved in the Seasonal Cycling of DMSP in the Southern Ocean
|
1543450 |
2020-08-01 | Countway, Peter | The Southern Ocean in the vicinity of Antarctica is a region characterized by seasonally-driven marine phytoplankton blooms that are often dominated by microalgal species which produce large amounts of dimethylsulfoniopropionate (DMSP). DMSP can be converted to the compound dimethylsulfide (DMS) which is a molecule that can escape into the atmosphere where it is known to have strong condensation properties that are involved in regional cloud formation. Production of DMSP can influence the diversity and composition of microbial assemblages in seawater and the types and activities of microbes in the seawater will likely affect the magnitude of DMSP\DMS production. The proposal aims to examine the role of DMSP in structuring the microbial communities in Antarctic waters and how this structuring may influence DMSP cycling. The project will leverage the Antarctic research to introduce concepts and data linking microbial diversity and biogeochemistry to a range of audiences (including high school and undergraduate students in Maine). The project will also engage teacher and students in rural K-8 schools and will allow a collaboration with a science writer and illustrator who will join the team in the field. The writer will use the southern ocean experience as the setting for a poster and a book about the proposed research and the scientists studying extreme environments. The project will examine (1) the extent to which the cycling of DMSP in southern ocean waters influences the composition and diversity of bacterial and protistan assemblages; (2) conversely, whether the composition and diversity of southern ocean protistan and bacterial assemblages influence the magnitude and rates of DMSP cycling; (3) the expression of DMSP degradation genes by marine bacteria seasonally and in response to additions of DMSP; and, to synthesize these results by quantifying (4) the microbial networks resulting from the presence of DMSP-producers and DMSP-consumers along with their predators, all involved in the cycling of DMSP in southern ocean waters. The work will be accomplished by conducting continuous growth experiments with DMSP-amended natural samples during field sampling of different microbial communities present in summer and fall. Data from the molecular (such as 16S/ 18S tag sequences, DMSP-cycle gene transcripts) and biogeochemical (such as biogenic sulfur cycling, bacterial production, microbial biomass) investigations will be integrated via network analysis. | POLYGON((-66 -63,-65.7 -63,-65.4 -63,-65.1 -63,-64.8 -63,-64.5 -63,-64.2 -63,-63.9 -63,-63.6 -63,-63.3 -63,-63 -63,-63 -63.3,-63 -63.6,-63 -63.9,-63 -64.2,-63 -64.5,-63 -64.8,-63 -65.1,-63 -65.4,-63 -65.7,-63 -66,-63.3 -66,-63.6 -66,-63.9 -66,-64.2 -66,-64.5 -66,-64.8 -66,-65.1 -66,-65.4 -66,-65.7 -66,-66 -66,-66 -65.7,-66 -65.4,-66 -65.1,-66 -64.8,-66 -64.5,-66 -64.2,-66 -63.9,-66 -63.6,-66 -63.3,-66 -63)) | POINT(-64.5 -64.5) | false | false | ||||||||||||||
Production and Fate of Oxylipins in Waters of the Western Antarctic Peninsula: Linkages Between UV Radiation, Lipid Peroxidation, and Carbon Cycling
|
1543328 |
2020-06-19 | Van Mooy, Benjamin |
|
The depletion of stratospheric ozone over Antarctica leads to abnormally high levels of ultraviolet radiation (UVR) from the sun reaching the surface of the ocean. This phenomenon is predicted to continue for the next half century, despite bans on ozone-destroying pollutants. Phytoplankton in the near surface ocean are subjected to variable amounts of UVR and contain a lot of lipids (fats). Because phytoplankton are at the base of the food chain their lipids makes their way into the Antarctic marine ecosystem's food web. The molecular structures of phytoplankton lipids are easily altered by UVR. When this happens, their lipids can be transformed from healthy molecules into potentially harmful molecules(oxylipins) known to be disruptive to reproductive and developmental processes. This project will use state-of-the-art molecular methods to answer questions about extent to which UVR damages lipid molecules in phytoplankton, and how these resultant molecules might effect the food chain in the ocean near Antarctica. Lipid peroxidation is often invoked as consequence of increased exposure of phytoplankton to UVR-produced reactive oxygen species (ROS), but the literature is practically silent on peroxidized lipids and their byproducts (i.e. oxylipins) in the ocean. In waters of the West Antarctic Peninsula (WAP), spring-time blooms of diatoms contribute significantly to overall marine primary production. Oxylipins from diatoms can be highly bioactive; their impact on zooplankton grazers, bacteria, and other phytoplankton has been the subject of intense study. However, almost all of this work has focused on the production of oxylipins via enzymatic pathways, not by pathways involving UVR and/or ROS. Furthermore, rigorous experimental work on the effects of oxylipins has been confined almost exclusively to pure cultures and artificial communities. Thus, the true potential of these molecules to disrupt carbon cycling is very poorly-constrained, and is entirely unknown in the waters of the WAP. Armed with new highly-sensitive, state-of-the-art analytical techniques based on high-mass-resolution mass spectrometry, the principal investigator and his research group have begun to uncover an exquisite diversity of oxylipins in natural WAP planktonic communities. These techniques will be applied to understand the connections between UVR, ROS, oxylipins, and carbon cycling. The project will answer the question of how UVR, via ROS, affects oxylipin production by diatoms in WAP surface waters in controlled experiments conducted at a field station. With the answer to this question in hand, the project will also seek to answer how this phenomenon impacts the flow of carbon, particularly the export of organic carbon from the system, during a research cruise. The level of UVR-induced stresses experienced by oxylipin-rich planktonic communities in the WAP is unique, making Antarctica the only location for answering these fundamental questions. Major activities will include laboratory experiments with artificial membranes and diatom cultures, as well field experiments with phytoplankton, zooplankton, and bacteria in WAP waters. | None | None | false | false | |||||||||||||
Collaborative Research: Sea ice as a driver of Antarctic benthic macroalgal community composition and nearshore trophic connectivity
|
1744570 1744550 1744584 1744602 |
2020-06-04 | Amsler, Charles; McClintock, James; Iken, Katrin; Galloway, Aaron; Klein, Andrew | 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. 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. 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. | 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)) | POINT(-65 -64.86) | false | false | ||||||||||||||
NSF-NERC: THwaites Offshore Research (THOR)
|
1738942 |
2019-11-01 | Wellner, Julia; Larter, Robert; Minzoni, Rebecca; Hogan, Kelly; Anderson, John; Graham, Alastair; Hillenbrand, Claus-Dieter; Nitsche, Frank O.; Simkins, Lauren; Smith, James A. | 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. 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. 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. | 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)) | POINT(-110 -73.5) | false | false | ||||||||||||||
Collaborative Research: Winter Survival Mechanisms and Adaptive Genetic Variation in an Antarctic Insect
|
1341385 1341393 |
2019-08-12 | Denlinger, David; Lee, Richard | Polar regions are deserts that are not only cold but also lack access to free water. Antarctic insects have unique survival mechanisms including the ability to tolerate freezing and extensive dehydration, surviving the loss of 70% of their body water. How this is done is of interest not only for understanding seasonal adaptations of insects and how they respond to climate change, but the molecular and physiological mechanisms employed may offer valuable insights into more general mechanisms that might be exploited for cryopreservation and long-term storage of human tissues and organs for transplantation and other medical applications. The investigators will study the proteins that are responsible for removing water from the body, cell level consequences of this, and how the responsible genes vary between populations. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. Each year a K-12 teacher will be a member of the field team and assist with fieldwork and outreach to school children and their teachers. Educational outreach efforts include presentations at local schools and national teacher meetings, providing lesson plans and podcasts on a website, and continuing to publish articles related to this research in education journals. In addition, undergraduate and graduate students will receive extensive training in all aspects of the research project with extended experiences that include publication of scientific papers and presentations at national meetings. This project focuses on deciphering the physiological and molecular mechanisms that enable the Antarctic midge Belgica antarctica to survive environmental stress and the loss of most of its body water in the desiccating polar environment. This extremophile is an ideal system for investigating mechanisms of stress tolerance and local geographic adaptations and its genome has recently been sequenced. This project has three focal areas: 1) Evaluating the role of aquaporins (water channel proteins) in the rapid removal of water from the body by studying expression of their genes during dehydration; 2) Investigating the mechanism of metabolic depression and the role of autophagy (controlled breakdown of cellular components) as a mediator of stress tolerance by studying expression of the genes responsible for autophagy during the dehydration process; and 3) Evaluating the population structure, gene flow, and adaptive variation in physiological traits associated with stress tolerance using a genetic approach that takes advantage of the genomic sequence available for this species coupled with physiological and environmental data from the sampled populations and their habitats. | 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)) | POINT(0 -89.999) | false | false | ||||||||||||||
Collaborative Research: Polynyas in Coastal Antarctica (PICA): Linking Physical Dynamics to Biological Variability
|
1643735 1643901 2021245 |
2019-08-07 | Zhang, Weifeng; Ji, Rubao; Jenouvrier, Stephanie; Maksym, Edward; Li, Yun |
|
During winter, sea-ice coverage along the Antarctic coast is punctuated by numerous polynyas--isolated openings of tens to hundreds of kilometer wide. These coastal polynyas are hotspots of sea ice production and the primary source regions of the bottom water in the global ocean. They also host high levels of biological activities and are the feeding grounds of Emperor penguins and marine mammals. The polynyas are a key component of the Antarctic coastal system and crucial for the survival of penguins and many other species. These features also differ dramatically from each other in timing of formation, duration, phytoplankton growth season, and overall biological productivity. Yet, the underlying reasons for differences among them are largely unknown. This project studies the fundamental biophysical processes at a variety of polynyas, examines the connection between the physical environment and the phytoplankton and penguin ecology, and investigates the mechanisms behind polynya variability. The results of this interdisciplinary study will provide a context for interpretation of field measurements in Antarctic coastal polynyas, set a baseline for future polynya studies, and examine how polynya ecosystems may respond to local and large-scale environmental changes. The project will include educational and outreach activities that convey scientific messages to a broad audience. It aims to increase public awareness of the interconnection between large-scale environmental change and Antarctic coastal systems. The main objectives of this study are to form a comprehensive understanding of the temporal and spatial variability of Antarctic coastal polynyas and the physical controls of polynya ecosystems. The project takes an interdisciplinary approach and seeks to establish a modeling system centered on the Regional Ocean Modeling System. This system links the ice and ocean conditions to the plankton ecology and penguin population. Applications of the modeling system in representative polynyas, in conjunction with analysis of existing observations, will determine the biophysical influences of individual forcing factors. In particular, this study will test a set of hypothesized effects of winds, offshore water intrusion, ice-shelf melting, sea-ice formation, glacier tongues, and ocean stratification on the timing of polynya phytoplankton bloom and the overall polynya biological productivity. The project will also examine how changing polynya state affects penguin breeding success, adult survival, and population growth. The team will conduct idealized sensitivity analysis to explore implications of forcing variability, including local and large-scale environmental change, on Antarctic coastal ecosystems. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Protein Folding and Embryogenesis in Antarctic Fishes: A Comparative Approach to Environmental Stress
|
1247510 |
2019-04-08 | Detrich, H. William | 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 REU undergraduate students to state-of-the-art biochemical, cellular, and molecular-biological research relevant to ecological and environmental issues of the Antarctic marine ecosystem. | None | None | false | false | ||||||||||||||
Workshop on Antarctic Surface Hydrology and Future Ice-shelf Stability
|
1743326 |
2019-03-26 | Kingslake, Jonathan; Tedesco, Marco; Trusel, Luke |
|
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 and review paper that will be broadly distributed. | None | None | false | false | |||||||||||||
Collaborative Research: The Chemical Ecology of Shallow-water Marine Macroalgae and Invertebrates on the Antarctic Peninsula - continuing
|
1341339 1341333 |
2019-03-05 | Amsler, Charles; Baker, Bill; McClintock, James | The coastal environments of the western Antarctic Peninsula harbor rich assemblages of marine animals and algae. The importance of the interactions between these groups of organisms in the ecology of coastal Antarctica are well known and often mediated by chemical defenses in the tissues of the algae. These chemicals are meant to deter feeding by snails and other marine animals making the Antarctic Peninsula an excellent place to ask important questions about the functional and evolutionary significance of chemical compound diversity for marine communities. This project will focus on three main objectives: the first objective is to expand the current understanding of the relationship between algae and their associated marine animals. The second objective focuses on the diversity of chemical compounds used to defend algae from being consumed. The third objective seeks to understand how marine animals can benefit from these compounds by consuming the algae that contain them, and then using those compounds to chemically deter predators. The field components of this research will be performed during three expeditions to the US Palmer Station, Antarctica. During these expeditions, a variety of laboratory feeding bioassays, manipulative field and laboratory experiments, and on-site chemical analyses will be performed. The investigators will also foster opportunities to integrate their NSF research with a variety of educational activities. As in the past they will support undergraduate research, both through NSF programs as well as home, university-based, programs, and they will also continue to support and foster graduate education. Through their highly successful University of Alabama in Antarctica interactive web program (two time recipient of awards of excellence from the US Council for Advancement and Support of Education), they will continue to involve large numbers of teachers, K-12 students, and other members of the community at large in their scientific endeavors in Antarctica. In addition, the investigators have hosted K-12 teachers on their Antarctic field teams through the former NSF Teachers Experiencing Antarctica and the Arctic program and will pursue participation in PolarTREC, the successor to this valuable program. Moreover, they will actively participate in outreach efforts by presenting numerous talks on their research to local school and community groups. The near shore environments of the western Antarctic Peninsula harbor rich assemblages of macroalgae and macroinvertebrates. The importance of predator-prey interactions and chemical defenses in mediating community-wide trophic interactions makes the western Antarctic Peninsula an excellent place to ask important questions about the functional and evolutionary significance of defensive compound diversity for marine communities. This project will focus on three main objectives which are a direct outcome of the past studies of the chemical ecology of shallow-water marine macroalgae and invertebrates on the Antarctic Peninsula by this group of investigators. The first objective is to expand the current understanding of a community-wide mutualism between macroalgae and their associated amphipods to include gastropods, which are also abundant on many macroalgae. The second objective focuses on the diversity of chemical compounds used to defend macroalgae from being consumed, particularly in the common red alga Plocamium cartilagineum. The third objective seeks to understand the relationship between P. cartilagineum and the amphipod Paradexamine fissicauda, including the ecological benefits and costs to P. fissicauda resulting from the ability to consume P. cartilagineum and other chemically defended red algae. The investigators will focus on the costs and benefits related to the ability of P. fissicauda to sequester defensive compounds from the alga P. cartilagineum and use those chemicals to defend itself from predation. The field components of this research will be performed during three expeditions to Palmer Station, Antarctica. During these expeditions, a variety of laboratory feeding bioassays, manipulative field and laboratory experiments, and on-site chemical analyses will be performed. Phylogenetic analyses, detailed secondary metabolite chemical analyses and purifications, and other data analyses will also be performed at the investigators' home institutions between and after their field seasons. | POLYGON((-65 -65,-64.8 -65,-64.6 -65,-64.4 -65,-64.2 -65,-64 -65,-63.8 -65,-63.6 -65,-63.4 -65,-63.2 -65,-63 -65,-63 -64.9,-63 -64.8,-63 -64.7,-63 -64.6,-63 -64.5,-63 -64.4,-63 -64.3,-63 -64.2,-63 -64.1,-63 -64,-63.2 -64,-63.4 -64,-63.6 -64,-63.8 -64,-64 -64,-64.2 -64,-64.4 -64,-64.6 -64,-64.8 -64,-65 -64,-65 -64.1,-65 -64.2,-65 -64.3,-65 -64.4,-65 -64.5,-65 -64.6,-65 -64.7,-65 -64.8,-65 -64.9,-65 -65)) | POINT(-64 -64.5) | false | false | ||||||||||||||
Assembling and Mining the Genomes of Giant Antarctic Foraminifera
|
1341612 |
2018-11-29 | Bowser, Samuel | Agglutinated foraminifera (forams for short) are early-evolving, single-celled organisms. These "living fossils" construct protective shells using sediment grains held together by adhesive substances that they secrete. During shell construction, agglutinated forams display amazing properties of selection - for example, some species build their shells of clear quartz grains, while other species use only grains of a specific size. Understanding how these single cells assemble complex structures may contribute to nanotechnology by enabling people to use forams as "cellular machines" to aid in the construction of nano-devices. This project will analyze the genomes of at least six key foram species, and then "mine" these genomes for technologically useful products and processes. The project will focus initially on the adhesive materials forams secrete, which may have wide application in biomedicine and biotechnology. Furthermore, the work will further develop a molecular toolkit which could open up new avenues of research on the physiology, ecology, and population dynamics of this important group of Antarctic organisms. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. Educational experiences related to the "thrill of scientific exploration and discovery" for students and the general public will be provided through freely-available short films and a traveling art/science exhibition. The project will also provide hands-on research opportunities for undergraduate students. Explorers Cove, situated on the western shore of McMurdo Sound, harbors a unique population of foraminiferan taxa at depths accessible by scuba diving that otherwise are primarily found in the deep sea. The project will use next-generation DNA sequencing and microdissection methods to obtain and analyze nuclear and mitochondrial genomes from crown members of two species each from three distinct, early-evolving foraminiferal groups. It will also use next generation sequencing methods to characterize the in-situ prokaryotic assemblages (microbiomes) of one of these groups and compare them to reference sediment microbiomes. The phyogenomic studies of the targeted Antarctic genera will help fill significant gaps in our current understanding of early foram evolution. Furthermore, comparative genomic analyses of these six species are expected to yield a better understanding of the physiology of single-chambered agglutinated forams, especially the bioadhesive proteins and regulatory factors involved in shell composition and morphogenesis. Additionally, the molecular basis of cold adaptation in forams will be examined, particularly with respect to key proteins. | None | None | false | false | ||||||||||||||
Collaborative Research: Flow and Fracture Dynamics in an Ice Shelf Lateral Margin: Observations and Modeling of the McMurdo Shear Zone
|
1245915 |
2018-09-27 | Ray, Laura |
|
Hamilton/1246400 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. | None | None | false | false | |||||||||||||
Impact of Supraglacial Lakes on Ice-Shelf Stability
|
1443126 |
2018-07-24 | MacAyeal, Douglas | Meltwater lakes that sit on top of Antarctica's floating ice shelves have likely contributed to the dramatic changes seen in Antarctica's glacial ice cover over the past two decades. In 2002, the 1,600-square-kilometer Larsen B Ice Shelf located on the Eastern side of the Antarctic Peninsula, for example, broke into thousands of small icebergs, which subsequently floated away as a result of the formation of more than 2,000 meltwater lakes on its surface over the prior decade. Our research project addresses the reasons why surface lakes form on Antarctic ice shelves and how these surface lakes subsequently contribute to the forces that may contribute to ice-shelf breakup like that of the Larsen B. Our project focuses primarily on making precise global positioning system (GPS) measurements of ice-shelf bending in response to the filling and draining of a surface lake on the McMurdo Ice Shelf. The observed vertical displacements (on the order of tens of centimeters) in response to lake filling will be used to calibrate and test computer simulation models that predict the response of ice shelves to surface lakes more generally and in a variety of future climate conditions. Our project will make hourly measurements of both vertical ice-shelf movements (using GPS surveying instruments) and of temperature and sunlight conditions (that drive melting) around a surface lake located close to the McMurdo Station airfield. Following this initial data-gathering effort, computer simulations and other more theoretical analysis will be undertaken to determine the suitability of the chosen McMurdo Ice Shelf surface lake as a field-laboratory for continued study. Ultimately, the research will contribute to understanding of the glaciological processes that link climate change to rising sea level. A successful outcome of the research will allow glaciologists to better assess the processes that promote or erode the influence Antarctic ice shelves have in controlling the transfer of ice from the interior of Antarctica into the ocean. The project will undertake two outreach activities: (1) web-posting of a field-activity journal and (2) establishing an open-access glaciological teaching and outreach web-sharing site for the International Glaciological Society. The proposed project seeks to experimentally verify a theory of ice-shelf instability proposed to explain the explosive break-up of Larsen B Ice Shelf in 2002. This theory holds that the filling and draining of supraglacial lakes on floating ice shelves induces sufficient flexure stress within the ice to (a) induce upward/downward propagating fractures originating at the base/surface of the ice shelf that (b) dissect the ice shelf into fragments that tend to have widths less than about half the ice thickness. The significance of narrow widths is that they promote capsize of the ice-shelf fragments during the break-up process. This capsize releases large amounts of gravitational potential energy (comparable to thousands of kilotons of TNT for the Larsen B Ice Shelf) thereby promoting explosiveness of the Larsen B event. The observational motivation for experimentally verifying the surface-lake mechanism for ice-shelf breakup is based on the fact that >2,000 surface lakes developed on the Larsen B Ice Shelf in the decade prior to its break up, and that these lakes were observed (via satellite imagery) to drain in a coordinated fashion during the day prior to the initiation of the break up. The field-observation component of the project will focus on a supraglacial lake on the McMurdo Ice Shelf where there is persistent summer season surface melting. The lake will be studied during a single provisional field season to determine whether grooming of surrounding surface streams and shorelines with heavy construction equipment will allow surface water to be manually encouraged to fill the lake. If successfully encouraged to develop, the McMurdo Ice Shelf surface lake will allow measurements of key ice-shelf flexure and stress variables needed to develop the theory of ice-shelf surface lakes without having to access the much more logistically demanding surface lakes of ice-shelves located elsewhere in Antarctica. Data to be gathered during the 6-week provisional field season include: energy- and water-balance parameters determining how the surface lake grows and fills, and various global positioning system measurements of the vertical bending of the ice sheet in response to the changing meltwater load contained within the surface lake. These data will be used to (1) constrain a computer model of viscoelastic flexure and possible fracture of the ice shelf in response to the increasing load of meltwater in the lake, and (2) determine whether continued study of the incipient surface-meltwater lake features on the McMurdo Ice Shelf provides a promising avenue for constraining the more-general behavior of surface meltwater lakes on other ice shelves located in warmer parts of Antarctica. Computer models constrained by the observational data obtained from the field project will inform energy- and water-balance models of ice shelves in general, and allow more accurate forecasts of changing ice-shelf conditions surrounding the inland ice of Antarctica. The project will create the first-ever ground-based observations useful for spawning the development of models capable of predicting viscoelastic and fracture behavior of ice shelves in response to supraglacial lake evolution, including slow changes due to energy balance effects, as well as fast changes due to filling and draining. | POLYGON((166.1631 -77.9007,166.19736 -77.9007,166.23162 -77.9007,166.26588 -77.9007,166.30014 -77.9007,166.3344 -77.9007,166.36866 -77.9007,166.40292 -77.9007,166.43718 -77.9007,166.47144 -77.9007,166.5057 -77.9007,166.5057 -77.90423,166.5057 -77.90776,166.5057 -77.91129,166.5057 -77.91482,166.5057 -77.91835,166.5057 -77.92188,166.5057 -77.92541,166.5057 -77.92894,166.5057 -77.93247,166.5057 -77.936,166.47144 -77.936,166.43718 -77.936,166.40292 -77.936,166.36866 -77.936,166.3344 -77.936,166.30014 -77.936,166.26588 -77.936,166.23162 -77.936,166.19736 -77.936,166.1631 -77.936,166.1631 -77.93247,166.1631 -77.92894,166.1631 -77.92541,166.1631 -77.92188,166.1631 -77.91835,166.1631 -77.91482,166.1631 -77.91129,166.1631 -77.90776,166.1631 -77.90423,166.1631 -77.9007)) | POINT(166.3344 -77.91835) | false | false | ||||||||||||||
Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island
|
0944021 0944307 0943466 |
2018-02-16 | Conway, Howard; Brook, Edward J.; Hawley, Robert L. | 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. | 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)) | POINT(-162 -79.25) | false | false | ||||||||||||||
Molecular Level Characterization of Dissolved Organic Carbon and Microbial Diversity in the WAIS Divide Replicate Core
|
1141936 |
2015-11-05 | Foreman, Christine |
|
This award supports a detailed, molecular level characterization of dissolved organic carbon and microbes in Antarctic ice cores. Using the most modern biological (genomic), geochemical techniques, and advanced chemical instrumentation researchers will 1) optimize protocols for collecting, extracting and amplifying DNA from deep ice cores suitable for use in next generation pyrosequencing; 2) determine the microbial diversity within the ice core; and 3) obtain and analyze detailed molecular characterizations of the carbon in the ice by ultrahigh resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS). With this pilot study investigators will be able to quantify the amount of material (microbial biomass and carbon) required to perform these characterizations, which is needed to inform future ice coring projects. The ultimate goal will be to develop protocols that maximize the yield, while minimizing the amount of ice required. The broader impacts include education and outreach at both the local and national levels. As a faculty mentor with the American Indian Research Opportunities and BRIDGES programs at Montana State University, Foreman will serve as a mentor to a Native American student in the lab during the summer months. Susan Kelly is an Education and Outreach Coordinator with a MS degree in Geology and over 10 years of experience in science outreach. She will coordinate efforts for comprehensive educational collaboration with the Hardin School District on the Crow Indian Reservation in South-central Montana. | POINT(112.085 -79.467) | POINT(112.085 -79.467) | false | false | |||||||||||||
Collaborative Research: Replicate Coring at WAIS Divide to Obtain Additional Samples at Events of High Scientific Interest
|
1043522 1043421 |
2015-07-13 | Severinghaus, Jeffrey P.; Brook, Edward J. |
|
1043421/Severinghaus This award supports a project to obtain samples of ice in selected intervals for replication and verification of the validity and spatial representativeness of key results in the WAIS Divide ice core, and to obtain additional ice samples in areas of intense scientific interest where demand is high. The US Ice Core Working Group recommended in 2003 that NSF pursue the means to take replicate samples, termed "replicate coring". This recommendation was part of an agreement to reduce the diameter of the (then) new drilling system (the DISC drill) core to 12.2 cm to lighten logistics burdens, and the science community accepted the reduction in ice sample with the understanding that replicate coring would be able to provide extra sample volume in key intervals. The WAIS Divide effort would particularly benefit from replicate coring, because of the unique quality of the expected gas record and the large samples needed for gases and gas isotopes; thus this proposal to employ replicate coring at WAIS Divide. In addition, scientific demand for ice samples has been, and will continue to be, very unevenly distributed, with the ice core archive being completely depleted in depth intervals of high scientific interest (abrupt climate changes, volcanic sulfate horizons, meteor impact horizons, for example). The broader impacts of the proposed research may include identification of leads and lags between Greenland, tropical, and Antarctic climate change, enabling critical tests of hypotheses for the mechanism of abrupt climate change. Improved understanding of volcanic impacts on atmospheric chemistry and climate may also emerge. This understanding may ultimately help improve climate models and prediction of the Earth System feedback response to ongoing human perturbation in coming centuries. Outreach and public education about climate change are integral components of the PIs' activities and the proposed work will enhance these efforts. Broader impacts also include education and training of 2 postdoctoral scholars and 1 graduate student, and invaluable field experience for the graduate and undergraduate students who will likely make up the core processing team at WAIS Divide. | POINT(-112.09 -79.47) | POINT(-112.09 -79.47) | false | false | |||||||||||||
Collaborative Research: Explosive Ice-Shelf Disintegration
|
0944193 |
2014-08-25 | MacAyeal, Douglas |
|
This award supports a project to examine and test a 3-step process model for explosive ice-shelf disintegration that emerged in the wake of the recent 2008 and 2009 events of the Wilkins Ice Shelf. The model is conditioned on Summer melt-driven increase in free-surface water coupled with surface and basal crevasse density growth necessary to satisfy an "enabling condition". Once met, the collapse proceeds through three steps: (Step 1), calving of a "leading phalanx" of tabular icebergs from the seaward ice front of the ice shelf which creates in its wake a region, called a "mosh pit" (located between the phalanx and the edge of the intact ice shelf), where ocean surface-gravity waves are trapped by reflection (a fast mechanically enabled process), (Step 2), and a rapid, runaway conversion of gravitational potential energy into ocean-wave energy by iceberg capsize and fragmentation within the "mosh pit" which leads to further wave-induced calving, capsize and fragmentation (Step 3). The project will be conducted by a multidisciplinary team and will focus on theoretical model development, numerical method development and application and new observations. The project will participate in both the Research Experience for Undergraduates program in the Physics Department and the Summer Research Early Identification Program (SR-EIP) that fosters participation in research by underrepresented minorities. The PIs, postdoctoral scholar, graduate students and unfunded participants will develop a graduate-level seminar/tutorial to introduce advanced computational methods to glaciology. A postdoctoral scholar and graduate student will be trained in new research techniques during the project. | None | None | false | false | |||||||||||||
Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines
|
0944475 |
2014-07-17 | Kaplan, Michael |
|
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. | 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)) | POINT(5.75 -85.75) | false | false | |||||||||||||
Model Studies of Surface Water Behavior on Ice Shelves
|
0944248 |
2013-12-21 | MacAyeal, Douglas |
|
MacAyeal/0944248<br/><br/>This award supports a project to develop a better understanding of the processes and conditions that trigger ice shelf instability and explosive disintegration. A significant product of the proposed research will be the establishment of parameterizations of micro- and meso-scale ice-shelf surface processes needed in large scale ice-sheet models designed to predict future sea level rise. The proposed research represents a 3-year effort to conduct numerical model studies of 6 aspects of surface-water evolution on Antarctic ice shelves. These 6 model-study areas include energy balance models of melting ice-shelf surfaces, with treatment of surface ponds and water-filled crevasses, distributed, Darcian water flow modeling to simulate initial firn melting, brine infiltration, pond drainage and crevasse filling, ice-shelf surface topography evolution modeling by phase change (surface melting and freezing), surface-runoff driven erosion and seepage flows, mass loading and flexure effects of ice-shelf and iceberg surfaces; feedbacks between surface-water loads and flexure stresses; possible seiche phenomena of the surface water, ice and underlying ocean that constitute a mechanism for, inducing surface crevassing., surface pond and crevasse convection, and basal crevasse thermohaline convection (as a phenomena related to area 5 above). The broader impacts of the proposed work bears on the socio-environmental concerns of climate change and sea-level rise, and will contribute to the important goal of advising public policy. The project will form the basis of a dissertation project of a graduate student whose training will contribute to the scientific workforce of the nation and the PI and graduate student will additionally participate in a summer science-enrichment program for high-school teachers organized by colleagues at the University of Chicago. | POLYGON((-63.72 -63.73,-62.893 -63.73,-62.066 -63.73,-61.239 -63.73,-60.412 -63.73,-59.585 -63.73,-58.758 -63.73,-57.931 -63.73,-57.104 -63.73,-56.277 -63.73,-55.45 -63.73,-55.45 -64.0876,-55.45 -64.4452,-55.45 -64.8028,-55.45 -65.1604,-55.45 -65.518,-55.45 -65.8756,-55.45 -66.2332,-55.45 -66.5908,-55.45 -66.9484,-55.45 -67.306,-56.277 -67.306,-57.104 -67.306,-57.931 -67.306,-58.758 -67.306,-59.585 -67.306,-60.412 -67.306,-61.239 -67.306,-62.066 -67.306,-62.893 -67.306,-63.72 -67.306,-63.72 -66.9484,-63.72 -66.5908,-63.72 -66.2332,-63.72 -65.8756,-63.72 -65.518,-63.72 -65.1604,-63.72 -64.8028,-63.72 -64.4452,-63.72 -64.0876,-63.72 -63.73)) | POINT(-59.585 -65.518) | false | false | |||||||||||||
Detangling Flow Regimes and Paleoclimate in the Deepest Section of the EDML Ice Core using U-series Ages.
|
1043367 |
2013-11-01 | Aciego, Sarah | No dataset link provided | Aciego/1043367 This award supports the development of a new method for determining the absolute age of samples from deep ice cores. The project will: (1) prove the efficacy of the Uranium-series dating method on a high accumulation rate ice core, and (2) address the uncertainties in the age dating of the EPICA Dronning-Maud Land (EDML) ice core in the lower 300 m. The well-dated upper section of the ice core (down to 150,000 years at 2415.7 m) will provide excellent constraints to validate the ages determined by the U-series method. After verification, and possible adjustments to the laboratory chemistry, the method will be applied to a suite of ice samples of unknown age in the lower part of the EDML ice core. Within the lower 300 m of this ice core, the climate records are disturbed by tilting and folding of the ice, and, due to the uncertainties in how the ice has flowed, it is impossible to determine if accurate age dates can be obtained to access the record of climate change, or if mixing of the ice is too incoherent. As part of the methodology, the PI will measure surface area of dust included in the ice using a gas adsorption technique developed for ultra-small samples; these measurements will be made on a BET nano-scale which is to be purchased from the funding of this project. Intellectual Merit: The proposed research will contribute to our understanding of geophysical processes that fold and tilt ice. This will allow new paleoclimate records to be recovered from ice cores that have been physically deformed and disturbed and previously did not permit accurate dating. Broader Impacts: This funding will provide support for one PhD graduate student and contribute to their training as a researcher in geochemistry and paleoclimate studies. The PI will teach classes in earth surface processes (including glaciology) and in advanced isotope geochemistry. Work related to this research will be integrated as a teaching tool into the classroom to provide a hands-on, relevant learning experience. Furthermore, samples examined as part of this research will be made available from the AWI archive in Bremerhaven, Germany as part of the collaboration between the PI in the United States and the European ice core community. | None | None | false | false | |||||||||||||
Collaborative Research: Photochemical and Optical Properties of Antarctic Waters in Response to Changing UV-B Fluxes
|
9527255 |
2010-05-04 | Mopper, Kenneth |
|
ACT K. Mopper & D. Kieber OPP 9527255 & OPP 9527314 PHOTOCHEMICAL AND OPTICAL PROPERTIES OF ANTARCTIC WATERS IN RESPONSE TO CHANGING UV-B FLUXES The decrease in stratospheric ozone over the Antarctic results in an increase in the UV-B flux in the euphotic zone. The increase leads to cellular damage to aquatic organisms, as documented by photo-inhibition and decreased productivity. Cellular damage can occur either intracellularly, or externally at the cell surface from biomolecular reactions with externally-generated reactive transients. The extent of this extracellular damage will depend on the photochemistry of the seawater surrounding the cell. Until recently, nothing was known about the type of photochemical processes, rates, and steady state concentrations of transients in Antarctic waters. It is proposed that field experiments be performed which will allow the construction of predictive models of photochemical production rates in surface waters and with depth. These studies will involve further quantum yield measurementts, development of a sensitive underwater actinometer system, and use of a new underwater multichannel photometer. The model will allow the prediction of the impact of varying levels of UV-B on the photoproduction and steady state concentration of several key reactive transient species in the upper water column. In addition to this effort, experiments will also be performed to study the photodegradation of dissolved organic matter and to determine whether biologically utilizable substrates that are formed photochemically can enhance secondary productivity in Antarctic waters. | None | None | false | false | |||||||||||||
Cold Body Temperature as an Evolutionary Shaping force in the Physiology of Antarctic Fishes
|
0125890 |
2010-05-04 | Sidell, Bruce; Detrich, H. William |
|
Notothenioid fishes that dominate the fish fauna surrounding Antarctica have been evolving for 10-14 million years at a nearly constant body temperature of ~0C throughout their life histories. As a result, this group of animals is uniquely suited to studies aimed at understanding and identifying features of physiology and biochemistry that result from the process of evolution at cold body temperature. This project has three major objectives aimed at examining adaptations for life in cold environments: <br/><br/>1. Identify the amino acid substitutions in the fatty acid-binding pocket of fatty acyl CoA synthetase (FACS) that explain its substrate specificity. Fatty acids are a major fuel of energy metabolism in Antarctic fishes. FACS catalyzes the condensation of CoASH and fatty acids to fatty acyl CoA esters, a step required for subsequent metabolism of these important compounds. This research may permit us to resolve the specific amino acid substitutions that explain both substrate specificity and preservation of catalytic rate of notothenioid FACS at cold physiological temperatures.<br/><br/>2. Produce a rigorous biochemical and biophysical characterization of the intracellular calcium-binding protein, parvalbumin, from white axial musculature of Antarctic fishes. Parvalbumin plays a pivotal role in facilitating the relaxation phase of fast-contracting muscles and is a likely site of strong selective pressure. Preliminary data strongly indicate that the protein from Antarctic fishes has been modified to ensure function at cold temperature. A suite of physical techniques will be used to determine dissociation constants of Antarctic fish parvalbumins for calcium and magnesium and unidirectional rate constants of ion-dissociation from the protein. Full-length cDNA clones for Antarctic fish parvalbumin(s) will permit deduction of primary amino acid sequence These data will yield insight into structural elements that permit the protein from notothenioid fishes to function at very cold body temperature.<br/><br/>3. Conduct a broad survey of the pattern of cardiac myoglobin expression in the Suborder Notothenoidei. Previous work has indicated a variable pattern of presence or absence of the intracellular oxygen-binding protein, myoglobin (Mb), in hearts of one family of Antarctic notothenioid fishes (Channichthyidae; icefishes). Because Mb is of physiological value in species that express the protein, the observed pattern of interspecific expression has been attributed to unusually low niche competition in the Southern Ocean. This leads to the prediction that similar loss of cardiac Mb should be observed in other notothenioid taxa. This part of the project will survey for the presence and absence of cardiac Mb in as many notothenioid species as possible and, if Mb-lacking species are detected, will extend analyses to determine the mechanism(s) responsible for loss of its expression using molecular biological techniques. | POLYGON((-68.1413 -52.6755,-67.47503 -52.6755,-66.80876 -52.6755,-66.14249 -52.6755,-65.47622 -52.6755,-64.80995 -52.6755,-64.14368 -52.6755,-63.47741 -52.6755,-62.81114 -52.6755,-62.14487 -52.6755,-61.4786 -52.6755,-61.4786 -53.8957,-61.4786 -55.1159,-61.4786 -56.3361,-61.4786 -57.5563,-61.4786 -58.7765,-61.4786 -59.9967,-61.4786 -61.2169,-61.4786 -62.4371,-61.4786 -63.6573,-61.4786 -64.8775,-62.14487 -64.8775,-62.81114 -64.8775,-63.47741 -64.8775,-64.14368 -64.8775,-64.80995 -64.8775,-65.47622 -64.8775,-66.14249 -64.8775,-66.80876 -64.8775,-67.47503 -64.8775,-68.1413 -64.8775,-68.1413 -63.6573,-68.1413 -62.4371,-68.1413 -61.2169,-68.1413 -59.9967,-68.1413 -58.7765,-68.1413 -57.5563,-68.1413 -56.3361,-68.1413 -55.1159,-68.1413 -53.8957,-68.1413 -52.6755)) | POINT(-64.80995 -58.7765) | false | false | |||||||||||||
Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica
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0440919 0440954 0551163 |
2009-10-12 | Miller, Molly; Sidor, Christian; Isbell, John | This project studies fossils from two to three hundred million year old rocks in the Allan Hills area of Antarctica. Similar deposits from lower latitudes have been used to develop a model of Permo-Triassic climate, wherein melting of continental glaciers in the early Permian leads to the establishment of forests in a cold, wet climate. Conditions became warmer and dryer by the early Triassic, inhibiting plant growth until a moistening climate in the late Triassic allowed plant to flourish once again. This project will test and refine this model and investigate the general effects of climate change on landscapes and ecosystems using the unique exposures and well-preserved fossil and sediment records in the Allan Hills area. The area will be searched for fossil forests, vertebrate tracks and burrows, arthropod trackways, and subaqueously produced biogenic structures, which have been found in other areas of Antarctica. Finds will be integrated with previous paleobiologic studies to reconstruct and interpret ecosystems and their changes. Structures and rock types documenting the end phases of continental glaciation and other major episodic sedimentations will also be described and interpreted. This project contributes to understanding the: (1) evolution of terrestrial and freshwater ecosystems and how they were affected by the end-Permian extinction, (2) abundance and diversity of terrestrial and aquatic arthropods at high latitudes, (3) paleogeographic distribution and evolution of vertebrates and invertebrates as recorded by trace and body fossils; and (3) response of landscapes to changes in climate.<br/><br/>In terms of broader impacts, this project will provide an outstanding introduction to field research for graduate and undergraduate students, and generate related opportunities for several undergraduates. It will also stimulate exchange of ideas among research and primarily undergraduate institutions. Novel outreach activities are also planned to convey Earth history to the general public, including a short film on the research process and products, and paintings by a professional scientific illustrator of Permo-Traissic landscapes and ecosystems. | POLYGON((159.3 -76.59,159.542 -76.59,159.784 -76.59,160.026 -76.59,160.268 -76.59,160.51 -76.59,160.752 -76.59,160.994 -76.59,161.236 -76.59,161.478 -76.59,161.72 -76.59,161.72 -76.811,161.72 -77.032,161.72 -77.253,161.72 -77.474,161.72 -77.695,161.72 -77.916,161.72 -78.137,161.72 -78.358,161.72 -78.579,161.72 -78.8,161.478 -78.8,161.236 -78.8,160.994 -78.8,160.752 -78.8,160.51 -78.8,160.268 -78.8,160.026 -78.8,159.784 -78.8,159.542 -78.8,159.3 -78.8,159.3 -78.579,159.3 -78.358,159.3 -78.137,159.3 -77.916,159.3 -77.695,159.3 -77.474,159.3 -77.253,159.3 -77.032,159.3 -76.811,159.3 -76.59)) | POINT(160.51 -77.695) | false | false | ||||||||||||||
Solar Activity during the Last Millennium, Estimated from Cosmogenic in-situ 14C in South Pole and GISP2 Ice Cores
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0538683 |
2009-02-20 | Lal, Devendra |
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0538683<br/>Lal<br/>This award supports a project to continue development of a new method for estimating solar activity in the past. It is based on measurements of the concentrations of in-situ produced C-14 in polar ice by cosmic rays, which depend only on (i) the cosmic ray flux, and (ii) ice accumulation rate. This is the only direct method available to date polar ice, since it does not involve any uncertain climatic transfer functions as are encountered in the applications of cosmogenic C-14 data in tree rings, or of Be-10 in ice and sediments. An important task is to improve on the temporal resolution during identified periods of high/low solar activity in the past 32 Kyr. The plan is to undertake a study of changes in the cosmic ray flux during the last millennium (1100-1825 A.D.), during which time 4 low and 1 high solar activity epoch has been identified from historical records. Sunspot data during most of these periods are sparse. Adequate ice samples are available from ice cores from the South Pole and from Summit, Greenland and a careful high resolution study of past solar activity levels during this period will be undertaken. The intellectual merit of the work includes providing independent verification of estimated solar activity levels from the two polar ice records of cosmic ray flux and greatly improve our understanding of solar-terrestrial relationships. <br/>The broader impacts include collaboration with other scientists who are experts in the application of the atmospheric cosmogenic C-14 and student training. Both undergraduates and a graduate student will be involved in the proposed research. Various forms of outreach will also be used to disseminate the results of this project, including public presentations and interactions with the media. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)
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9911617 9319379 |
2009-02-06 | Carter, Sasha P.; Holt, John W.; Blankenship, Donald D.; Morse, David L.; Dalziel, Ian W. | 9911617 Blankenship 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. 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. - 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. - 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. - 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. - 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. - 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. - SOAR will repair and/or refurbish equipment that was used during the 2000/01 field campaign. 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. | None | None | false | false | ||||||||||||||
Collaborative Research: Millennial Scale Fluctuations of Dry Valleys Lakes: Implications for Regional Climate Variability and the Interhemispheric (a)Synchrony of Climate Change
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0124049 |
2008-08-25 | Berger, Glenn; Hall, Brenda; Doran, Peter | No dataset link provided | 0124049<br/>Berger<br/><br/>This award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the Dry Valleys of the McMurdo Sound region of Antarctica. Using a modified Livingstone corer, transects of long cores will be obtained from Lakes Fryxell, Bonney, Joyce, and Vanda. A multiparameter approach will be employed which is designed to extract the greatest possible amount of former water-level, glaciological, and paleoenvironmental data from Dry Valleys lakes. Estimates of hydrologic changes will come from different proxies, including grain size, stratigraphy, evaporite mineralogy, stable isotope and trace element chemistry, and diatom assemblage analysis. The chronology, necessary to integrate the cores with the geomorphological record, as well as for comparisons with Antarctic ice-core and glacial records, will come from Uranium-Thorium, Uranium-Helium, and Carbon-14 dating of carbonates, as well as luminescence sediment dating. Evaluation of the link between lake-level and climate will come from hydrological and energy-balance modelling. Combination of the more continuous lake-core sequences with the spatially extensive geomorphological record will result in an integrated Antarctic lake-level and paleoclimate dataset that extends back at least 30,000 years. This record will be compared to Dry Valleys glacier records and to the Antarctic ice cores to address questions of regional climate variability, and then to other Southern Hemisphere and Northern Hemisphere records to assess interhemispheric synchrony or asynchrony of climate change. | POLYGON((161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.20000000000002 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163.20000000000002 -77.5,163.4 -77.5,163.4 -77.52,163.4 -77.54,163.4 -77.56,163.4 -77.58,163.4 -77.6,163.4 -77.62,163.4 -77.64,163.4 -77.66,163.4 -77.68,163.4 -77.7,163.20000000000002 -77.7,163 -77.7,162.8 -77.7,162.6 -77.7,162.4 -77.7,162.20000000000002 -77.7,162 -77.7,161.8 -77.7,161.6 -77.7,161.4 -77.7,161.4 -77.68,161.4 -77.66,161.4 -77.64,161.4 -77.62,161.4 -77.6,161.4 -77.58,161.4 -77.56,161.4 -77.54,161.4 -77.52,161.4 -77.5)) | POINT(162.4 -77.6) | false | false | |||||||||||||
Collaborative Research: Trapped Gas Composition and the Chronology of the Vostok Ice Core
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0230448 0230260 |
2006-01-18 | Battle, Mark; Bender, Michael; Suwa, Makoto; Severinghaus, Jeffrey P. |
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High latitude deep ice cores contain fundamental records of polar temperatures, atmospheric dust loads (and continental aridity), greenhouse gas concentrations, the status of the biosphere, and other essential properties of past environments. An accurate chronology for these records is needed if their significance is to be fully realized. The dating challenge has stimulated efforts at orbital tuning. In this approach, one varies a timescale, within allowable limits, to optimize the match between a paleoenvironmental property and a curve of insolation through time. The ideal property would vary with time due to direct insolation forcing. It would be unaffected by complex climate feedbacks and teleconnections, and it would give a clean record with high signal/noise ratio. It is argued strongly that the O2/N2 ratio of ice core trapped gases is such a property, and evidence is presented that this property, whose atmospheric ratio is nearly constant, is tied to local summertime insolation. This award will support a project to analyze the O2/N2 ratios at 1 kyr intervals from ~ 115-400 ka in the Vostok ice core. Ancillary measurements will be made of Ar/N2, and Ne/N2 and heavy noble gas ratios, in order to understand bubble close-off fractionation and its manifestation in the Vostok trapped gas record. O2/N2 variations will be matched with summertime insolation at Vostok to achieve a high-accuracy chronology for the Vostok core. The Vostok and other correlatable climate records will then be reexamined to improve our understanding of the dynamics of Pleistocene climate change. | POLYGON((-75.34 86.6,-68.742 86.6,-62.144 86.6,-55.546 86.6,-48.948 86.6,-42.35 86.6,-35.752 86.6,-29.154 86.6,-22.556 86.6,-15.958 86.6,-9.36 86.6,-9.36 83.618,-9.36 80.636,-9.36 77.654,-9.36 74.672,-9.36 71.69,-9.36 68.708,-9.36 65.726,-9.36 62.744,-9.36 59.762,-9.36 56.78,-15.958 56.78,-22.556 56.78,-29.154 56.78,-35.752 56.78,-42.35 56.78,-48.948 56.78,-55.546 56.78,-62.144 56.78,-68.742 56.78,-75.34 56.78,-75.34 59.762,-75.34 62.744,-75.34 65.726,-75.34 68.708,-75.34 71.69,-75.34 74.672,-75.34 77.654,-75.34 80.636,-75.34 83.618,-75.34 86.6)) | POINT(106.8 -72.4667) | false | false | |||||||||||||
Digital Imaging for Ice Core Analysis
|
9615554 |
2003-05-14 | Fitzpatrick, Joan; Alley, Richard; Spencer, Matthew |
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This award is for support for two years to develop the technology and methodology for digitizing the photographs and analyzing the thin sections from ice cores. In addition, the application of digital technology for whole-core stratigraphy, using digital photography, image enhancement and image processing will be investigated. The thin section analysis will be piloted with samples already in hand from the Taylor Dome ice core. If successful, these techniques will be applied to samples from the Siple Dome ice core, in cooperation with Principal Investigators already funded to retrieve and examine these sections. The original digital images with all original data annotation files will be distributed to Siple Dome principal investigators for their use in the interpretation of their own data. All software and hardware acquired for this project will become part of the permanent equipment inventory at the U.S. National Ice Core Laboratory and will be available for use by clients at the facility. | None | None | false | false | |||||||||||||
Physical and Structural Properties of the Siple Dome Core
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9527262 |
2003-05-14 | Gow, Tony; Meese, Deb |
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This award is for support for a program to investigate the visual stratigraphy, index physical properties, relaxation characteristics and crystalline structure of ice cores from Siple Dome, West Antarctica. This investigation will include measurements of a time-priority nature that must be initiated at the drill site on freshly-drilled cores. This will be especially true of cores from the brittle ice zone, which is expected to comprise a significant fraction of the ice core. The brittle zone includes ice in which relaxation , resulting from the release of confining pressure is maximized and leads to significant changes in the mechanical condition of the core that must be considered in relation to the processing and analysis of ice samples for entrapped gas and chemical studies. This relaxation will be monitored via precision density measurements made initially at the drill site and repeated at intervals back in the U.S. Other studies will include measurement of the annual layering in the core to as great a depth as visual stratigraphy can be deciphered, crystal size measurements as a function of depth and age, c-axis fabric studies, and analysis of the physical properties of any debris-bearing basal ice and its relationship to the underlying bedrock. Only through careful documentation and analysis of these key properties can we hope to accurately assess the dynamic state of the ice and the age-depth relationships essential to deciphering the paleoclimate record at this location. | None | None | false | false | |||||||||||||
Retrieval and Analysis of Extraterrestrial Particles from the Water Well at the South Pole Station, Antarctica
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9316715 |
2002-01-01 | Taylor, Susan |
|
9316715 Taylor This award is for support to collect micrometeorites from the bottom of the new water well at South Pole Station, Antarctica. The large volume of firn and ice being melted provides the concentrating mechanism needed to collect large numbers of micrometeorites that occur in low concentrations in the ice. The first task of the project is to design a collection system to retrieve the micrometeorites from the bottom of the water well. The collector must be reliable, easy to operate, must collect all particles larger than 10 mm and should not contaminate the well's water quality. Following successful design and deployment of the collector, recovered particles will be catalogued and distributed to interested researchers. *** | None | None | false | false | |||||||||||||
Siple Dome Glaciology and Ice Stream History
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9316338 |
1999-01-01 | Jacobel, Robert |
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9316338 Jacobel This award is for support for a program of glaciological studies of Siple Dome and its surroundings between Ice Streams C and D. The purpose of the work is to characterize the dynamic environment and ice stratigraphy to aid in the assessment of Siple Dome as a potential deep ice core site, and to determine whether the configuration of ice stream flow in the region was different in the past than now. The work involves measurements of the configuration and continuity of internal layers in the ice, using radar echo sounding and determination of velocity field, based on standard GPS surveying. The goals of the work are relevant to understanding the dynamics of the West Antarctic Ice Sheet (WAIS), its past history and its potential future behavior, including possible effects on global sea level. This work is a collaborative project between the University of Washington, the University of Colorado and St. Olaf College. *** | None | None | false | false |