[{"awards": "2333917 Dong, Xiaoli", "bounds_geometry": "POLYGON((161 -77.5,161.1 -77.5,161.2 -77.5,161.3 -77.5,161.4 -77.5,161.5 -77.5,161.6 -77.5,161.7 -77.5,161.8 -77.5,161.9 -77.5,162 -77.5,162 -77.51,162 -77.52,162 -77.53,162 -77.53999999999999,162 -77.55,162 -77.56,162 -77.57,162 -77.58,162 -77.58999999999999,162 -77.6,161.9 -77.6,161.8 -77.6,161.7 -77.6,161.6 -77.6,161.5 -77.6,161.4 -77.6,161.3 -77.6,161.2 -77.6,161.1 -77.6,161 -77.6,161 -77.58999999999999,161 -77.58,161 -77.57,161 -77.56,161 -77.55,161 -77.53999999999999,161 -77.53,161 -77.52,161 -77.51,161 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 27 Feb 2025 00:00:00 GMT", "description": "Ecosystems worldwide are threatened by anthropogenic changes in climate. Lakes are widely regarded as sentinels of climate change and, among these, polar lakes are the most sensitive. Beneath meters of permanent ice and liquid water, many Antarctic lakes contain complex microbial communities that are already being transformed by climate change. The structurally complex spatial patterns that these microbes create provide the opportunity to pursue research questions about spatial ecology that cannot be addressed elsewhere. This project focuses on research that will advance understanding of the spatial structure of benthic communities in Antarctic lakes, their relationships with environmental conditions, and predictions for likely changes in the future. This project will also advance methods in integrating the morphology and spatial patterning of modern microbial communities in relationship to their biophysical and biochemical environments. The quantitative framework being developed has potential to refine understanding of controls on microbial community patterning and thus interpretation of both the effects of climate change and ancient fossil microbial communities in the geologic record. Such understanding will address key questions about Earth\u2019s evolutionary and environmental history and future. Lake Vanda in the McMurdo Dry Valleys, Antarctic, has modern microbial pinnacles covering its lake floor. Using existing datasets on spatial structure of benthic communities from 37 sites on the floor of Lake Vanda, the project team will apply recent theories from Spatial Ecology to investigate the mechanisms that give rise to spatial patterns of pinnacles formed by benthic microbes. The work addresses two questions: (1) What are the morphological and spatial patterns of pinnacles and how do they vary over developmental stages, along environment gradients, and from 2013 to 2023? And (2) what mechanisms give rise to the geometry of individual pinnacles and their spatial distribution? Lake Vanda provides an exceptional opportunity to address these questions. It features well characterized gradients in sedimentation, nutrients, irradiance, transport mechanism, and colonization history. Benthic communities at different locations in the lake manifest distinct spatial patterns, as they experience distinct conditions. Lake level has increased \u003e10 m in the past few decades, creating additional opportunities for a \u201cnatural experiment\u201d on pattern development by comparing relatively newly flooded substrates (pinnacles of 1 to 15 years old) with deeper, well-developed mats (\u003e 70 years old). Since microbial communities respond to environmental change rapidly, analyses can characterize changes in patterns in pinnacle spatial data collected 9 years apart (Dec 2013 and Jan 2023), providing the opportunity to directly assess responses of spatially self-organized ecosystems to environmental change. As such, Lake Vanda is a natural laboratory that allows research (1) to effectively sort out mechanisms of pattern formation affecting benthic microbial communities residing there; and (2) to test the theory of spatial self-organization: mechanisms of pattern formation and responses to perturbations, applicable to ecosystems worldwide. Research questions will be addressed by integrating existing datasets, spatial pattern analyses, Bayesian statistical models, and process-based numerical models. 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": 162.0, "geometry": "POINT(161.5 -77.55)", "instruments": null, "is_usap_dc": true, "keywords": "Lake Vanda; ECOLOGICAL DYNAMICS", "locations": "Lake Vanda", "north": -77.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Dong, Xiaoli; Sumner, Dawn", "platforms": null, "repositories": null, "science_programs": null, "south": -77.6, "title": "Effects of Environmental Change on Microbial Self-organized Patterns in Antarctic Lakes", "uid": "p0010499", "west": 161.0}, {"awards": "1744651 Wilcock, William", "bounds_geometry": "POLYGON((-62 -62,-61.5 -62,-61 -62,-60.5 -62,-60 -62,-59.5 -62,-59 -62,-58.5 -62,-58 -62,-57.5 -62,-57 -62,-57 -62.2,-57 -62.4,-57 -62.6,-57 -62.8,-57 -63,-57 -63.2,-57 -63.4,-57 -63.6,-57 -63.8,-57 -64,-57.5 -64,-58 -64,-58.5 -64,-59 -64,-59.5 -64,-60 -64,-60.5 -64,-61 -64,-61.5 -64,-62 -64,-62 -63.8,-62 -63.6,-62 -63.4,-62 -63.2,-62 -63,-62 -62.8,-62 -62.6,-62 -62.4,-62 -62.2,-62 -62))", "dataset_titles": "3D P-wave velocity models of Orca Volcano, Bransfield Basin, Antarctica from the\r\nBRAVOSEIS experiment; Bransfield OBSIC OBS network 2019-20 (network code ZX, 2019); BRAVOSEIS Onshore Seismic Array (Network code 5M)", "datasets": [{"dataset_uid": "200440", "doi": "", "keywords": null, "people": null, "repository": "NSF SAGE Facility DMC", "science_program": null, "title": "Bransfield OBSIC OBS network 2019-20 (network code ZX, 2019)", "url": " https://ds.iris.edu/mda/18-017/"}, {"dataset_uid": "200441", "doi": "10.14470/0Z7563857972", "keywords": null, "people": null, "repository": "GEOFON", "science_program": null, "title": "BRAVOSEIS Onshore Seismic Array (Network code 5M)", "url": "https://doi.org/10.14470/0Z7563857972"}, {"dataset_uid": "200442", "doi": "in progress", "keywords": null, "people": null, "repository": "Marine Geoscience Data System", "science_program": null, "title": "3D P-wave velocity models of Orca Volcano, Bransfield Basin, Antarctica from the\r\nBRAVOSEIS experiment", "url": ""}], "date_created": "Fri, 14 Feb 2025 00:00:00 GMT", "description": "One of the fundamental processes in plate tectonics is the rifting or separating of continental crust creating new seafloors which can widen and ultimately form new ocean basins, the latter is a process known as seafloor spreading. The Bransfield Strait, separating the West Antarctic Peninsula from the South Shetland Islands, formed and is presently widening as a result of the separation of continental crust. What is unique is that the system appears to be approaching the transition to seafloor spreading making this an ideal site to study the transitional process. Previous seafloor mapping and field surveys provide the regional structure of the basin; however, there exists a paucity of regional seismic studies documenting the tectonic and volcanic activity in the basin as a result of the rifting. This would be the first local-scale study of the seismicity and structure of the volcanoes in the center of the basin where crustal separation is most active. The new seismic data will enable scientists to compare current patterns of crustal separation and volcanism at the Bransfield Strait to other well-studied seafloor spreading centers. This collaborative international project, led by the Spanish and involving scientists from the U.S., Germany and other European countries, will monitor seismicity for one year on land and on the seafloor. An active seismic study conducted by the Spanish will image fault and volcanic structures that can be related to the distribution of earthquakes. Back-arc basins are found in subduction settings and form in two stages, an initial interval of continental rifting that transitions to a later stage of seafloor spreading. Studying the transitional process is important for understanding the dynamics and evolution of subduction zones, and in locations where back-arc rifting breaks continental crust, it is relevant to understanding the formation of passive continental margins. The Central Bransfield Basin is unusual in that the South Shetland Islands have lacked recent arc volcanism and it appears subduction is ceasing, but this system has broad significant because it appears to be nearing the transition from rifting to seafloor spreading. This award will support the U.S. component of an international initiative led by the Spanish Polar Committee to conduct a study of the seismicity and volcanic structure of the Central Bransfield Basin. The objective is to characterize the distribution of active extension across the basin and determine whether the volcanic structure and deformation of the rift are consistent with a back-arc basin that is transitioning from rifting to seafloor spreading. The U.S. component of the experiment will contribute a network of six hydroacoustic moorings to monitor regional seismicity and 15 short-period seismometers to study the distribution of tectonic and volcanic seismicity on Orca volcano, one of the most active volcanoes in the basin. An active seismic study across closely spaced multichannel seismic lines across the rift will provide the data necessary to link earthquakes with fault structures enabling a tomography study of Orca volcano and provide insight into how the volcano\u0027s structure relates to rifting. This research will constrain the distribution of active rifting across the Central Bransfield Basin and determine whether the patterns of faulting and the structure of volcanic portion of the rift are consistent with a diffuse zone of rifting or a single spreading center that is transitioning to the production of oceanic crust. The Bransfield Basin is an ideal site for a comparative study of seismic and hydroacoustic earthquake locations that will improve the understanding of the generation and propagation of T-wave signals and contribute to efforts to compare the result of T-wave studies with data from traditional solid-earth seismic studies. 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": -57.0, "geometry": "POINT(-59.5 -63)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e AIRGUN ARRAYS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e PASSIVE ACOUSTIC RECORDER", "is_usap_dc": true, "keywords": "Back Arc Basin; SHIPS; TECTONICS; PLATE TECTONICS; South Shetland Islands; Bransfield Strait; MARINE GEOPHYSICS; Antarctic Peninsula", "locations": "Bransfield Strait; South Shetland Islands; Antarctic Peninsula", "north": -62.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "NOT APPLICABLE", "persons": "William, Wilcock; Dax, Soule; Robert, Dziak", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "NSF SAGE Facility DMC", "repositories": "GEOFON; Marine Geoscience Data System; NSF SAGE Facility DMC", "science_programs": null, "south": -64.0, "title": "Collaborative Research: The Tectonic and Magmatic Structure and Dynamics of Back-arc Rifting in Bransfield Strait: An International Seismic Experiment", "uid": "p0010498", "west": -62.0}, {"awards": "2015878 O\u0027\u0027Brien, Kristin", "bounds_geometry": null, "dataset_titles": "Survey of US Antarctic biological collections", "datasets": [{"dataset_uid": "601862", "doi": "10.15784/601862", "keywords": "Antarctica; Cryosphere", "people": "O\u0027Brien, Kristin", "repository": "USAP-DC", "science_program": null, "title": "Survey of US Antarctic biological collections", "url": "https://www.usap-dc.org/view/dataset/601862"}], "date_created": "Tue, 03 Dec 2024 00:00:00 GMT", "description": "This workshop will bring together Antarctic marine freshwater and terrestrial biologists, students, and experts in specimen curation to assess the value of, need for, and scope of a biological repository of Antarctic specimens, including tissue samples. Currently, some US collected Antarctic specimen collections are housed in various museums, repositories, and labs. These collections are not easily discoverable on the internet, and how well they represent the biodiversity of Antarctica is largely unknown. The workshop coordinators will advertise the conference broadly and recruit underrepresented groups to participate. Participants will assess current repositories and determine how to make Antarctica biological samples more accessible in a unified location (or through better coordination). This effort will benefit the broader community of biologists working with Antarctic organisms by providing opportunities to conduct Antarctic science by investigators and their students that might otherwise not be possible due to the logistical and budget challenges for deployments. Following workshop activities, a final report will be published on the outcomes of the efforts. 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": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; ANIMALS/INVERTEBRATES", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Polar Cyberinfrastructure; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "O\u0027Brien, Kristin", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: A Workshop for Evaluating the Value and Scope of a Biological Repository of Antarctic Specimens", "uid": "p0010491", "west": null}, {"awards": "2042032 Huckstadt, Luis", "bounds_geometry": null, "dataset_titles": "Crabeater seal tracking data 2022-2023", "datasets": [{"dataset_uid": "601861", "doi": "10.15784/601861", "keywords": "Antarctica; Cryosphere", "people": "Huckstadt, Luis", "repository": "USAP-DC", "science_program": null, "title": "Crabeater seal tracking data 2022-2023", "url": "https://www.usap-dc.org/view/dataset/601861"}], "date_created": "Wed, 27 Nov 2024 00:00:00 GMT", "description": "Part I: Non-technical description: The crabeater seal is the most important predator of Antarctic krill in the western Antarctic Peninsula oceanic waters after the disappearance of large whales due to human hunting 100 years ago. The crabeater seals are expected to consume large quantities of krill due to their high abundance (about 7 million individuals), large body size (about 700 pounds in body weight), high metabolism and a diet specializing in krill. This species depends on sea ice presence all year long, living, reproducing, and diving to feed from that environment, making this marine mammal species a good indicator, or sentinel, of how the Antarctic ecosystem responds to a changing climate. As sea ice has been decreasing in the northern Antarctic Peninsula, this project aims to understand if the species food availability has changed in the last decades in response to environmental changes. In particular, the proposed work will concentrate on known populations of crabeater seals in northern (i.e., warmer, sub-polar) and southern (i.e., colder, polar) Antarctic Peninsula, 450 miles apart, making measurements on the abundance, physiology, metabolic needs and movement of the crabeater populations in both locations. The data will be combined to build models that will quantify the existing differences between northern and southern populations, as well as predict their future change, and compare present-day measurements with those collected by the British Antarctic Survey in the mid-1900s. The project is a collaboration between an international and interdisciplinary team from the United States and United Kingdom, benefitting NSF goals to facilitate collaborative geoscience research projects involving these two countries as well as aligning directly with U.S. Global Change Research Program (USGCRP) to better understand the forces shaping the global environment, both human and natural, and their impacts on society. To further increase polar literacy and education, Principal Investigators will train at least 2 graduate students and several undergraduates across two US institutions, as well as one UK-based post-doctoral researcher. Part II: Technical description: Crabeater seals (Lobodon carcinophaga) are considered an excellent sentinel species through which to examine the effects of a changing climate on the extended Antarctic krill-dependent predator community and the structure of the entire ecosystem of the western Antarctic Peninsula. Over the last forty years, there have been significant changes in the temporal and spatial patterns of primary productivity, and shifts in the population dynamics of Antarctic krill, the dominant mid-trophic level species. The impact of such changes on year-round resident species of crabeater seals (the most important predator of Antarctic krill) is more difficult to understand as they are not associated with breeding colonies where their population fluctuations could be more readily observed. The proposed research is conceived under the premise that environmental change has accentuated the differences between the northern and southern western Antarctic Peninsula crabeater seal populations due to differential reductions in sea-ice and its possible effect on prey availability. To address this question, this research will combine measurements on animal movement, stable isotope analyses, whole-animal physiology, and novel survey technologies (small Unmanned Aircraft Systems, satellite imagery) to build models. The project is a collaboration between an international and interdisciplinary team from the United States and United Kingdom. These studies will be essential to detect past, and project future, changes in the ecology of this species in response to changes in sea ice when comparing present-day measurements with those collected by the British Antarctic Survey in the mid-1900s. To further increase polar literacy and education, Principal Investigators will train at least 2 graduate students and several undergraduates across two US institutions, as well as one UK-based post-doctoral researcher. Students involved with this project will gain invaluable research experience in the lab and will have a unique opportunity to participate in Antarctic fieldwork. 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": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "ANIMAL ECOLOGY AND BEHAVIOR; MARINE ECOSYSTEMS; Antarctica", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Huckstadt, Luis", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "NSFGEO-NERC Collaborative Research: Effects of a Changing Climate on the Habitat Utilization, Foraging Ecology and Distribution of Crabeater Seals", "uid": "p0010490", "west": null}, {"awards": "2317995 Herman, Rachael", "bounds_geometry": "POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.5,-55 -62,-55 -62.5,-55 -63,-55 -63.5,-55 -64,-55 -64.5,-55 -65,-55 -65.5,-55 -66,-56 -66,-57 -66,-58 -66,-59 -66,-60 -66,-61 -66,-62 -66,-63 -66,-64 -66,-65 -66,-65 -65.5,-65 -65,-65 -64.5,-65 -64,-65 -63.5,-65 -63,-65 -62.5,-65 -62,-65 -61.5,-65 -61))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 04 Oct 2024 00:00:00 GMT", "description": "Gentoo penguins (Pygoscelis papua) inhabit one of the fastest warming regions on Earth, the Western Antarctic Peninsula (WAP), where environmental shifts are measured in years, not decades. Despite this, the species is flourishing, growing in numbers and colonizing new habitats while sister species, such as Ad\u00e9lie penguins (P. adeliae), are declining in the region. This project will investigate to what extent epigenetics contributes to the success of gentoo penguins. Epigenetic variation is controlled by modifications to DNA or chromatin structure that affect the expression of genes, rather than changes to the underlying DNA sequence. This project will improve the understanding of gentoo penguin adaptation to climate change, and whether it is a result of increased flexibility in behavior and physiology driven by a greater capacity for epigenetic changes (i.e., epigenetic potential). The most studied form of epigenetic variation is the profiling of DNA methylation patterns. Environmental effects can trigger changes in DNA methylation that target specific tissues, allowing for localized gene expression shifts that result in modifications to the phenotype of an organism without any alteration to the underlying genotype. Given that epigenetic variation between populations often exceeds genetic variation, fine-scale genetic differentiation observed amongst gentoo penguin colonies suggests the possibility for local adaptation via even more divergent epigenetic changes and provides a framework for examining epigenetic variation across the gentoo penguin breeding range along multiple ecological axes. The researchers will test this by comprehensively characterizing the epigenomic profiles via patterns of DNA methylation in wild gentoo and Ad\u00e9lie penguins using cutting-edge high-resolution genomics techniques. Specifically, they will investigate whether gentoo penguins exhibit a greater degree of differences in DNA-methylation than underlying genetic differences, suggesting such epigenetic variation is driven by external environmental variables, potentially leading to improved capacity for local adaptation. This project will explore whether epigenetic potential may be selected for in individuals who disperse to new colony locations by comparing older, established colonies to new colonies at the range-edge. By implementing cutting-edge epigenetic methods in wild populations of gentoo penguins, this project will help address ecological questions on environmental plasticity that will impact conservation efforts and decisions on Marine Protected Areas (MPAs) on the Antarctic Peninsula. 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": -55.0, "geometry": "POINT(-60 -63.5)", "instruments": null, "is_usap_dc": true, "keywords": "Gentoo Penguin; ECOLOGICAL DYNAMICS; Adaptation; Methylation; Antarctic Peninsula; Climate Change; Epigenetic Variation; PENGUINS", "locations": "Antarctic Peninsula", "north": -61.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Post Doc/Travel", "paleo_time": null, "persons": "Herman, Rachael", "platforms": null, "repositories": null, "science_programs": null, "south": -66.0, "title": "Postdoctoral Fellowship: OPP-PRF: Epigenetic Potential as a Driver of Local Adaptation in Gentoo Penguins (Pygoscelis Papua) along the Western Antarctic Peninsula", "uid": "p0010477", "west": -65.0}, {"awards": null, "bounds_geometry": null, "dataset_titles": "The Impacts of the Microstructural Location of H2SO4 on the Flow of Polycrystalline Ice", "datasets": [{"dataset_uid": "601831", "doi": "10.15784/601831", "repository": "USAP-DC", "science_program": null, "title": "The Impacts of the Microstructural Location of H2SO4 on the Flow of Polycrystalline Ice", "url": "http://www.usap-dc.org/view/dataset/601831"}], "date_created": "Thu, 05 Sep 2024 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Cryosphere", "locations": "Antarctica", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Ogunmolasuyi, Ayobami", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "2420219 Chignell, Stephen", "bounds_geometry": "POLYGON((160 -76.5,160.45 -76.5,160.9 -76.5,161.35 -76.5,161.8 -76.5,162.25 -76.5,162.7 -76.5,163.15 -76.5,163.6 -76.5,164.05 -76.5,164.5 -76.5,164.5 -76.7,164.5 -76.9,164.5 -77.1,164.5 -77.3,164.5 -77.5,164.5 -77.7,164.5 -77.9,164.5 -78.1,164.5 -78.3,164.5 -78.5,164.05 -78.5,163.6 -78.5,163.15 -78.5,162.7 -78.5,162.25 -78.5,161.8 -78.5,161.35 -78.5,160.9 -78.5,160.45 -78.5,160 -78.5,160 -78.3,160 -78.1,160 -77.9,160 -77.7,160 -77.5,160 -77.3,160 -77.1,160 -76.9,160 -76.7,160 -76.5))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 13 Aug 2024 00:00:00 GMT", "description": "Geodiversity is the variety of non-living elements like rocks, landforms, and processes in a given area, and plays an especially critical role in Antarctica. Geodiversity provides the conditions in which life can develop and underpins all ecosystems on Earth. It also provides tangible services to people (like construction materials) as well as intangible benefits (such as scientific knowledge from ice cores and artistic inspiration from glaciers). Despite its importance, Antarctic geodiversity remains under-explored, under-described, and inadequately mapped. This knowledge gap is particularly concerning given the threats posed by increasing human activity and environmental and climate change. This project uses a variety of datasets to map Antarctic geodiversity, assess its benefits to people, and help identify priority locations for conservation. Through an interdisciplinary and mixed-method approach, this research will fill a major gap in the current understanding and representations of the Antarctic. Using the McMurdo Dry Valleys as a case study, the researcher will combine geospatial data on geology, geomorphology, pedology, and hydrology to map geodiversity of the region. This project will identify sites of key geosystem services by analyzing geospatial data on placenames, scientific samples, and a web-based participatory mapping survey. The geodiversity and geosystem services data will then be overlaid and combined to identify hotspots of geo-social diversity. The resulting maps will be compared with the region\u0027s protected area boundaries to assess the fit-for-purpose of current environmental management and identify priority locations for future research and conservation. The fellow will promote Antarctic geodiversity broadly, including at UNESCO International Geodiversity Day. 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": 164.5, "geometry": "POINT(162.25 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "McMurdo Dry Valleys; LANDSCAPE; ROCKS/MINERALS/CRYSTALS; LANDFORMS; GIS; GLACIAL LANDFORMS; RIVERS/STREAMS", "locations": "McMurdo Dry Valleys", "north": -76.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Chignell, Stephen", "platforms": null, "repositories": null, "science_programs": null, "south": -78.5, "title": "Postdoctoral Fellowship: OPP-PRF: Mapping Antarctic Geodiversity: Assessing People, Place, and Abiotic Nature in the McMurdo Dry Valleys", "uid": "p0010476", "west": 160.0}, {"awards": "0087144 Conway, Howard", "bounds_geometry": "POLYGON((-150 -83.5,-148 -83.5,-146 -83.5,-144 -83.5,-142 -83.5,-140 -83.5,-138 -83.5,-136 -83.5,-134 -83.5,-132 -83.5,-130 -83.5,-130 -83.65,-130 -83.8,-130 -83.95,-130 -84.1,-130 -84.25,-130 -84.4,-130 -84.55,-130 -84.7,-130 -84.85,-130 -85,-132 -85,-134 -85,-136 -85,-138 -85,-140 -85,-142 -85,-144 -85,-146 -85,-148 -85,-150 -85,-150 -84.85,-150 -84.7,-150 -84.55,-150 -84.4,-150 -84.25,-150 -84.1,-150 -83.95,-150 -83.8,-150 -83.65,-150 -83.5))", "dataset_titles": "Impulse HF radar data from Conway Ridge", "datasets": [{"dataset_uid": "601810", "doi": "10.15784/601810", "keywords": "Antarctica; Cryosphere; Siple Coast", "people": "Hoffman, Andrew; Conway, Howard; Christianson, Knut", "repository": "USAP-DC", "science_program": null, "title": "Impulse HF radar data from Conway Ridge", "url": "https://www.usap-dc.org/view/dataset/601810"}], "date_created": "Mon, 22 Jul 2024 00:00:00 GMT", "description": "Marine ice sheets are low-pass filters of climate variability that take centuries to adjust to interior and near-terminus changes in mass balance. Constraining these century-scale changes from satellite observations that span only the last 40 years is challenging. Here, we take a different approach of carefully synthesizing different data sets to infer changes in the configurations of van der Veen and Mercer Ice Streams on the Siple Coast over the past 3000 years from englacial features encoded in ice-penetrating radar data. Englacial radar data from Conway Ridge reveal smooth, surface conformal layers overlying disrupted stratigraphy that suggest the van der Veen Ice Stream was 40 km wider over 3000 years ago. Englacial layer dating indicates that the ice stream narrowed to its present configuration between $\\sim3000$ and $\\sim1000$ years ago. Similarly disrupted stratigraphy and buried crevasses suggest that ice flowing from Mercer to Whillans Ice Stream across the northwestern tip of the ridge slowed shortly after. Using an ice-flow model capable of simulating shear margin migration, we evaluate whether small changes in ice thickness can lead to large changes in shear margin location. Our results suggest that the tip of Conway Ridge is sensitive to thinning and thickening, and that when the basal strength at the tip of the ridge increases with the height above flotation, the ice sheet shear margins can change quickly.", "east": -130.0, "geometry": "POINT(-140 -84.25)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIER ELEVATION/ICE SHEET ELEVATION; Siple Coast", "locations": "Siple Coast", "north": -83.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hoffman, Andrew; Conway, Howard", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Glacial History of Ridge AB, West Antarctica", "uid": "p0010470", "west": -150.0}, {"awards": "2209726 Lindzey, Laura", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "QIceRadar Antarctic Index of Radar Depth Sounding Data", "datasets": [{"dataset_uid": "200413", "doi": " 10.5281/zenodo.12123013", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "QIceRadar Antarctic Index of Radar Depth Sounding Data", "url": "https://zenodo.org/records/12123013"}], "date_created": "Wed, 19 Jun 2024 00:00:00 GMT", "description": "Ice penetrating radar is one of the primary tools that researchers use to study ice sheets and glaciers. With radar, it is possible to see a cross-section of the ice, revealing internal layers and the shape of the rocks under the ice. Among other things, this is important for calculating how much potential sea level change is locked up in the polar ice sheets, and how stable the ice sheets are likely to be in a warming world. This type of data is logistically challenging and expensive to collect. Historically, individual research groups have obtained funding to collect these data sets, and then the data largely stayed within that institution. There has been a recent push to make more and more data openly available, enabling the same datasets to be used by multiple research groups. However, it is still difficult to figure out what data is available because there is no centralized index. Additionally, each group releases data in a different format, which creates an additional hurdle to its use. This project addresses both of those challenges to data reuse by providing a unified tool for discovering where ice penetrating radar data already exists, then allowing the researcher to download and visualize the data. It is integrated into open-source mapping software that many in the research community already use, and makes it possible for non-experts to explore these datasets. This is particularly valuable for early-career researchers and for enabling interdisciplinary work. The US alone has spent many tens of millions of dollars on direct grants to enable the acquisition and analysis of polar ice penetrating radar data, and even more on the associated infrastructure and support costs. Unfortunately, much of these data is not publicly released, and even the data that has been released is not easily accessible. There is significant technical work involved in figuring out how to locate, download and view the data. This project is developing a tool that will both lower the barrier to entry for using this data and improve the workflows of existing users. Quantarctica and QGreenland have rapidly become indispensable tools for the polar research community, making diverse data sets readily available to researchers. However, ice penetrating radar is a major category of data that is not currently supported \u2013 it is possible to see the locations of existing survey lines, and the ice thickness maps that have been interpreted from their data, but it is not readily possible to see the radargrams themselves in context with all of the other information. This capability is important because there is far more visual information contained in a radargram than simply its interpreted basal elevation or ice thickness. This project is developing software that will enable researchers to to view radargram images and interpreted surface and basal horizons in context with the existing map-view datasets in Quantarctica and QGreenland. A data layer shows the locations of all known ice penetrating radar surveys, color-coded based on availability. This layer enables data discovery and browsing. The plugin itself interacts with the data layer, first to download selected data, then to visualize the radargrams along with a cursor that moves simultaneously along the radargram and along the map view, making it straightforward to determine the precise geolocation of radar features. 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": "AIRCRAFT; GLACIERS/ICE SHEETS; Antarctica", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Polar Cyberinfrastructure", "paleo_time": null, "persons": "Lindzey, Laura", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e AIRCRAFT", "repo": "Zenodo", "repositories": "Zenodo", "science_programs": null, "south": -90.0, "title": "Elements: Making Ice Penetrating Radar More Accessible: A tool for finding, downloading and visualizing georeferenced radargrams within the QGIS ecosystem", "uid": "p0010464", "west": -180.0}, {"awards": "2207011 Granger, Julie", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 04 Mar 2024 00:00:00 GMT", "description": "Phytoplankton are microscopic single-celled plants that grow at the sun-lit surface of the ocean. In the Southern Ocean around Antarctica, phytoplankton live in sub-optimal conditions because the amount of iron in seawater is insufficient for growth. Moreover, the chemical composition of Southern Ocean phytoplankton is distinct from that in other ocean regions, with a higher proportion of phosphorus relative to other elements, a characteristic that ultimately influences the distribution of nutrients ocean-wide. The researchers hypothesize that the high phosphorus composition of phytoplankton in the Southern Ocean is caused by their low iron content. Specifically, they postulate that a phosphorus-rich molecule, phytic acid, is synthesized by phytoplankton in order to assist in the storage of iron in designated cellular compartments, such as vacuoles. Recent observations show that some phytoplankton can absorb phytic acid, suggesting that it may be produced by certain species. Phytic acid is pervasive in soils, wherein it aids absorption of iron via plant roots and could similarly help phytoplankton in the Southern Ocean acquire iron via the cell membranes. This project benefits the National Science Foundation\u0027s goals of improving understanding of interactions between the Southern Ocean and the global ocean, of expanding fundamental knowledge of Antarctic biota and associated processes by focusing on phytoplankton species unique to the Antarctic. As part of this project, the Department of Marine Sciences from the College of Liberal Arts and Sciences at the University of Connecticut will sponsor the recruitment, relocation and mentorship of a graduate student under-represented in the sciences. This project aims to determine whether the unusual elemental composition of phytoplankton at the Southern Ocean is a result of anemia. The work will query whether inositol hexakisphosphate (phytic acid) aids Antarctic phytoplankton acquire and store iron, resulting in an elevated fraction of cellular phosphorus relative to other elements. The researchers, including a graduate student, will conduct laboratory culture experiments with phytoplankton strains isolated from the Southern Ocean. They will grow cells in iron- deficient versus iron-replete media to see if their phosphorus content is higher in iron-deficient conditions. They will test whether cells grown with sufficient phosphorus acquire more iron, allowing them to grow better in iron-deficient conditions than cells deriving from phosphorus-poor conditions. They will also query whether cells grown in iron-deficient conditions achieve faster growth rates in the presence of phytic acid. Results will inform the design of CRISPR mutants with which to investigate phosphorus and iron co-metabolism in Antarctic marine phytoplankton. 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": "Dinoflagellates; Iron; United States Of America; Iron Acquisition; Siderophore; TRACE ELEMENTS; Iron Limitation", "locations": "United States Of America", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Granger, Julie; Lin, Senjie", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Siderophore utilization by dinoflagellates as a strategy for iron acquisition", "uid": "p0010455", "west": -180.0}, {"awards": "2023355 Schmandt, Brandon", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "A seismic catalog for the southernmost continent", "datasets": [{"dataset_uid": "601805", "doi": "10.15784/601805", "keywords": "Antarctica; Cryosphere; Earthquakes; Icequakes; Volcanic Events", "people": "Pena Castro, Andres", "repository": "USAP-DC", "science_program": null, "title": "A seismic catalog for the southernmost continent", "url": "https://www.usap-dc.org/view/dataset/601805"}], "date_created": "Tue, 20 Feb 2024 00:00:00 GMT", "description": "Part 1: Nontechnical Unlike other locations on the globe Antarctica is not known for having large earthquakes and the remote nature and harsh conditions make it difficult to install and maintain seismometers for earthquake detection. Some researchers believe the lack of large earthquakes is due to the continent being surrounded by inactive tectonic margins. However, in the last two decades, scientists have discovered that more earthquakes occur in the interior of the continent than previously observed. This suggests that there are many earthquakes missing from historic earthquake catalogs. This study aims to find the missing earthquakes using novel earthquake detection and location techniques from seismic data collected from temporary and permanent seismic stations in Antarctica over the last 25 years. Locating these earthquakes will help understand if and where earthquakes are located in Antarctica and will help in planning future seismic deployments. As part of the project broader impacts, a field expedition with the Girls on Rock program will be conducted to teach high school age girls, and especially those from underrepresented backgrounds, data visualization techniques using scientific data. Part 2: Technical The spatial distribution of seismicity and the number of moderate magnitude earthquakes in Antarctica is not well-defined. The current catalog of earthquakes may be biased by uneven and sparse seismograph distribution on the continent. We will mine existing broadband seismic data from both permanent and temporary deployments to lower the earthquake detection threshold across Interior Antarctica, with a focus on tectonic earthquakes. The hypothesis is that Interior Antarctica has abundant moderate magnitude earthquakes, previously undetected. These earthquakes are likely collocated with major tectonic features such as the Transantarctic Mountains, the suspected Vostok collision zone, the West Antarctic Rift System, the crustal compositional boundary between East and West Antarctica, and the Cretaceous East Antarctic Rift. Previous seismic deployments have recorded earthquakes in the Antarctic interior, suggesting there are many earthquakes missing from the current catalog. We propose to use novel earthquake location techniques designed for automated detection and location using 25 years of continuous data archived at IRIS from PASSCAL experiments and permanent stations. The approach will use STA/LTA detectors on the first arrival P-wave to 90 degrees distance, Reverse Time Imaging to locate events, and beamforming at dense arrays strategically located on cratons for enhanced detection and location. The combination of detection and location techniques used in this work has not been used on teleseismic body waves, although similar methods have worked well for surface wave studies. If successful the project would provide an excellent training dataset for future scrutiny of newly discovered Antarctic seismicity with machine learning approaches and/or new targeted data collection. We plan to collaborate with Girls on Rock, a local and international organization committed to building a culturally diverse community in science, art, and wilderness exploration, in a summer field expedition and integrating computer coding into post-field scientific projects. 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": "Antarctica; Seismic Events; Icequakes; TECTONICS; Earthquakes", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Polar Special Initiatives", "paleo_time": null, "persons": "Schmandt, Brandon", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "EAGER: Lowering the detection threshold of Antarctic seismicity to reveal undiscovered intraplate deformation", "uid": "p0010450", "west": -180.0}, {"awards": null, "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 12 Feb 2024 00:00:00 GMT", "description": "Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function.\u003cbr/\u003e \u003cbr/\u003e \u003cbr/\u003eTo understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Palmer Station; BENTHIC; PENGUINS; FLUORESCENCE; PHYTOPLANKTON", "locations": "Palmer Station", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": null, "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Physical Mechanisms Driving Food Web Focusing in Antarctic Biological Hotspots", "uid": "p0010448", "west": null}, {"awards": "2325922 Couradeau, Estelle", "bounds_geometry": "POLYGON((-73.783 4.679,-73.7827 4.679,-73.7824 4.679,-73.7821 4.679,-73.7818 4.679,-73.7815 4.679,-73.7812 4.679,-73.7809 4.679,-73.7806 4.679,-73.7803 4.679,-73.78 4.679,-73.78 4.6789,-73.78 4.6788,-73.78 4.6787,-73.78 4.6786,-73.78 4.6785,-73.78 4.6784,-73.78 4.6783,-73.78 4.6782,-73.78 4.6781,-73.78 4.678,-73.7803 4.678,-73.7806 4.678,-73.7809 4.678,-73.7812 4.678,-73.7815 4.678,-73.7818 4.678,-73.7821 4.678,-73.7824 4.678,-73.7827 4.678,-73.783 4.678,-73.783 4.6781,-73.783 4.6782,-73.783 4.6783,-73.783 4.6784,-73.783 4.6785,-73.783 4.6786,-73.783 4.6787,-73.783 4.6788,-73.783 4.6789,-73.783 4.679))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 06 Feb 2024 00:00:00 GMT", "description": "P\u00e1ramos are high-altitude tundra ecosystems nested at the heart of the Andes mountains. These cold and humid environments are home to a multitude of plants, animals, and insects. P\u00e1ramos are a critical water source for downstream urban centers, including Colombia\u0027s capital city, Bogota. Additionally, the P\u00e1ramos soils contain substantial organic carbon reserves due to slow rates of organic matter decomposition. Beyond being a pool of carbon sequestered away from the atmosphere, this large reservoir of organic matter controls the soils\u2019 hydraulic and fertility properties. The P\u00e1ramos\u2019 unique geographic location, at an elevation above 2,800 m above sea level, makes them highly vulnerable to the impacts of climate change. In fact, these ecosystems\u2019 surface areas are projected to shrink by half within the next 50 years possibly causing loss of the essential services they provide. This project aims to characterize the microbial diversity in the P\u00e1ramos soils in Colombia and investigate how climate change will affect microbes\u2019 functions. The research is of high importance, considering that immediate and long-term changes in microbial metabolism could impact the ability of P\u00e1ramos soils to store organic carbon and regulate downstream water flow. To study the cascading effect of climate change on P\u00e1ramos ecosystems, this project will jumpstart collaborations among transdisciplinary experts that will integrate the research of below-ground microbial communities with above-ground vegetation functions. The project will also engage high school and undergraduate students that will work together to develop and deploy low-cost long-term soil monitoring data loggers in Chingaza National Natural Park, near the city of Bogota. This project will address the critical need to disentangle the effect of moisture and temperature on the fate of organic carbon in P\u00e1ramos soils while building a transdisciplinary team capable of expanding the scope of the research to an ecosystem level. The project includes establishing controlled soil mesocosms that will allow to independently vary moisture and temperature levels. Additionally, functions of the soil microbiome will be investigated using metagenomics and amplicon sequencing, and probes will be deployed to initiate long-term monitoring of the soil response to climate change in situ. This project will culminate in the organization of an international P\u00e1ramos symposium that will set up priorities for future systems research. The symposium will bring together scientists from diverse fields to discuss the linkages between above-ground and below-ground ecosystem functions and plan future collaborations in predicting P\u00e1ramos-wide effects of climate change. 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": -73.78, "geometry": "POINT(-73.7815 4.6785)", "instruments": null, "is_usap_dc": true, "keywords": "TERRESTRIAL ECOSYSTEMS; Chingaza Paramos Colombia; ORGANIC MATTER; SOIL MECHANICS", "locations": "Chingaza Paramos Colombia", "north": 4.679, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Couradeau, Estelle; Maximova, Siela; Machado, Jose Luis", "platforms": null, "repositories": null, "science_programs": null, "south": 4.678, "title": "Collaborative Research: BoCP-Design: Climate change alteration of soils functional biodiversity of the P\u00e1ramos, Colombia", "uid": "p0010445", "west": -73.783}, {"awards": "2333940 Zhong, Shijie", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 08 Jan 2024 00:00:00 GMT", "description": "Satellite observations of Earth\u2019s surface gravity and elevation changes indicate rapid melting of ice sheets in recent decades in northern Antarctica Peninsula and Amundsen Sea Embayment of West Antarctica. This rapid melting may lead to significant global sea level rise which is a major societal concern. Measurements from the Global Positioning System (GPS) show rapid land uplift in these regions as the ice sheets melt. When an ice sheet melts, the melt water flows to oceans, causing global sea level to rise. However, the sea level change at a given geographic location is also influenced by two other factors associated with the ice melting process: 1) the vertical motion of the land and 2) gravitational attraction. The vertical motion of the land is caused by the change of pressure force on the surface of the solid Earth. For example, the removal of ice mass reduces the pressure force on the land, leading to uplift of the land below the ice sheet, while the addition of water in oceans increases the pressure force on the seafloor, causing it to subside. The sea level always follows the equipotential surface of the gravity which changes as the mass on the Earth\u2019s surface (e.g., the ice and water) or/and in its interiors (e.g., at the crust-mantle boundary) is redistributed. Additionally, the vertical motion of the land below an ice sheet has important effects on the evolution and stability of the ice sheet and may determine whether the ice sheet will rapidly collapse or gradually stabilize. The main goal of this project is to build an accurate and efficient computer model to study the displacement and deformation of the Antarctic crust and mantle in response to recent ice melting. The project will significantly improve existing and publicly available computer code, CitcomSVE. The horizontal and vertical components of the Earth\u2019s surface displacement depends on mantle viscosity and elastic properties of the Earth. Although seismic imaging studies demonstrate that the Antarctica mantle is heterogeneous, most studies on the ice-melting induced deformation in Antarctica have assumed that mantle viscosity and elastic properties only vary with the depth due to computational limitations. In this project, the new computational method in CitcomSVE avoids such assumptions and makes it possible to include realistic 3-D mantle viscosity and elastic properties in computing the Antarctica crustal and mantle displacement. This project will interpret the GPS measurements of the surface displacements in northern Antarctica Peninsula and Amundsen Sea Embayment of West Antarctica and use the observations to place constraints on mantle viscosity and deformation mechanisms. The project will also seek to predict the future land displacement Antarctica, which will lead to a better understand of Antarctica ice sheets. Finally, the project has direct implications for the study of global sea level change and the dynamics of the Greenland ice sheet. Technical Description Glacial isostatic adjustment (GIA) is important for understanding not only fundamental science questions including mantle viscosity, mantle convection and lithospheric deformation but also societally important questions of global sea-level change, polar ice melting, climate change, and groundwater hydrology. Studies of rock deformation in laboratory experiments, post-seismic deformation, and mantle dynamics indicate that mantle viscosity is temperature- and stress-dependent. Although the effects of stress-dependent (i.e., non-Newtonian) viscosity and transient creep rheology on GIA process have been studied, observational evidence remains elusive. There has been significant ice mass loss in recent decades in northern Antarctica Peninsula (NAP) and Amundsen Sea Embayment (ASE) of West Antarctica. The ice mass loss has caused rapid bedrock uplift as measured by GPS techniques which require surprisingly small upper mantle viscosity of ~1018 Pas. The rapid uplifts may have important feedback effects on ongoing ice melting because of their influence on grounding line migration, and the inferred small viscosity may have implications for mantle rheology and deformation on decadal time scales. The main objective of the project is to test hypotheses that the GPS observations in NAP and ASE regions are controlled by 3-D non-Newtonian or/and transient creep viscosity by developing new GIA modeling capability based on finite element package CitcomSVE. The project will carry out the following three tasks: Task 1 is to build GIA models for the NAP and ASE regions to examine the effects of 3-D temperature-dependent mantle viscosity on the surface displacements and to test hypothesis that the 3-D mantle viscosity improves the fit to the GPS observations. Task 2 is to test the hypothesis that non-Newtonian or/and transient creep rheology controls GIA process on decadal time scales by computing GIA models and comparing model predictions with GPS observations for the NAP and ASE regions. Task 3 is to implement transient creep (i.e., Burgers model) rheology into finite element package CitcomSVE for modeling the GIA process on global and regional scales and to make the package publicly available to the scientific community. The project will develop the first numerical GIA model with Burgers transient rheology and use the models to examine the effects of 3-D temperature-dependent viscosity, non-Newtonian viscosity and transient rheology on GIA-induced surface displacements in Antarctica. The project will model the unique GPS observations of unusually large displacement rates in the NAP and ASE regions to place constraints on mantle rheology and to distinguish between 3-D temperature-dependent, non-Newtonian and transient mantle viscosity. The project will expand the capability of the publicly available software package CitcomSVE for modeling viscoelastic deformation and tidal deformation on global and regional scales. The project will advance our understanding in lithospheric deformation and mantle rheology on decadal time scales, which helps predict grounding line migration and understand ice sheet stability in West Antarctica. The project will strengthen the open science practice by improving the publicly available code CitcomSVE at github. 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": "WAIS; CRUSTAL MOTION; COMPUTERS; GLACIER MASS BALANCE/ICE SHEET MASS BALANCE", "locations": "WAIS", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Zhong, Shijie", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Investigating Effects of Transient and Non-Newtonian Mantle Viscosity on Glacial Isostatic Adjustment Process and their Implications for GPS Observations in Antarctica", "uid": "p0010441", "west": -180.0}, {"awards": "2317263 Cross, Andrew", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 14 Aug 2023 00:00:00 GMT", "description": "The seaward motion of ice sheets and glaciers is primarily controlled by basal sliding at the base of the ice sheet and internal viscous flow within the ice mass. The latter of these \u2014 viscous flow \u2014 is dependent on various factors, including temperature, stress, grain size, and the alignment of ice crystals during flow to produce a \"crystal orientation fabric\" (COF). Historically, ice flow has been modeled using an equation, termed \u201cGlen\u2019s law\u201d, that describes ice-flow rate as a function of temperature and stress. Glen\u2019s law was constrained under relatively high-stress conditions and is often attributed to the motion of crystal defects within ice grains. More recently, however, grain boundary sliding (GBS) has been invoked as the rate-controlling process under low-stress, \u201csuperplastic\u201d conditions. The grain boundary sliding hypothesis is contentious because GBS is not thought to produce a COF, whereas geophysical measurements and polar ice cores demonstrate strong COFs in polar ice masses. However, very few COF measurements have been conducted on ice samples subjected to superplastic flow conditions in the laboratory. This project would measure the evolution of ice COF across the transition from superplastic to Glen-type creep. Results will be used to interrogate the role of superplastic GBS creep within polar ice masses, and thereby provide constraints on polar ice discharge models. Polycrystalline ice samples with grain sizes ranging from 5 \u00b5m to 1000 \u00b5m will be fabricated and deformed in a laboratory, using a 1-atm cryogenic axial-torsion apparatus. Experiments will be conducted at temperatures of -30\u00b0C to -10\u00b0C, and at a constant uniaxial strain rate. Under these conditions, 5% to 99.99% of strain should be accommodated by superplastic, GBS-limited creep, depending on the sample grain size. The deformed samples will then be imaged using cryogenic electron backscatter diffraction (cryo-EBSD) and high-angular-resolution electron backscatter diffraction (HR-EBSD) to quantify COF, grain size, grain shape, and crystal defect (dislocation) densities, among other microstructural properties. These measurements will be used to decipher the rate-controlling mechanisms operating within different thermomechanical regimes, and resolve a long-standing debate over whether superplastic creep can produce a COF in ice. In addition to the polycrystal experiments, ice bicrystals will be fabricated and deformed to investigate the micromechanical behavior of individual grain boundaries under superplastic conditions. Ultimately, these results will be used to provide a microstructural toolbox for identifying superplastic creep using geophysical (e.g., seismic, radar) and glaciological (e.g., ice core) observations. This project will support one graduate student, one or more undergraduate summer students, and an early-career researcher. In addition, this project will support a workshop aimed at bringing together experimentalists, glaciologists, and ice modelers to facilitate cross-disciplinary knowledge sharing and collaborative problem solving. 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": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "United States Of America; Rheology; ROCKS/MINERALS/CRYSTALS; GLACIERS/ICE SHEETS", "locations": "United States Of America", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Cross, Andrew", "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Microstructural Evolution during Superplastic Ice Creep", "uid": "p0010430", "west": null}, {"awards": "1644234 Phillips, Fred", "bounds_geometry": "POLYGON((166.17 -77.3,166.32799999999997 -77.3,166.486 -77.3,166.644 -77.3,166.802 -77.3,166.95999999999998 -77.3,167.118 -77.3,167.276 -77.3,167.434 -77.3,167.59199999999998 -77.3,167.75 -77.3,167.75 -77.34,167.75 -77.38,167.75 -77.42,167.75 -77.46,167.75 -77.5,167.75 -77.54,167.75 -77.58,167.75 -77.62,167.75 -77.66,167.75 -77.7,167.59199999999998 -77.7,167.434 -77.7,167.276 -77.7,167.118 -77.7,166.95999999999998 -77.7,166.802 -77.7,166.644 -77.7,166.486 -77.7,166.32799999999997 -77.7,166.17 -77.7,166.17 -77.66,166.17 -77.62,166.17 -77.58,166.17 -77.54,166.17 -77.5,166.17 -77.46,166.17 -77.42,166.17 -77.38,166.17 -77.34,166.17 -77.3))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 12 Dec 2022 00:00:00 GMT", "description": "Nontechnical Description: The age of rocks and soils at the surface of the Earth can help answer multiple questions that are important for human welfare, including: when did volcanoes erupt and are they likely to erupt again? when did glaciers advance and what do they tell us about climate? what is the frequency of hazards such as landslides, floods, and debris flows? how long does it take soils to form and is erosion of soils going to make farming unsustainable? One method that is used thousands of times every year to address these questions is called \u0027cosmogenic surface-exposure dating\u0027. This method takes advantage of cosmic rays, which are powerful protons and neutrons produced by supernova that constantly bombard the Earth\u0027s atmosphere. Some cosmic rays reach Earth\u0027s surface and produce nuclear reactions that result in rare isotopes. Measuring the quantity of the rare isotopes enables the length of time that the rock or soil has been exposed to the atmosphere to be calculated. The distribution of cosmic rays around the globe depends on Earth\u0027s magnetic field, and this distribution must be accurately known if useful exposure ages are to be obtained. Currently there are two remaining theories, narrowed down from many, of how to calculate this distribution. Measurements from a site that is at both high altitude and high latitude (close to the poles) are needed to test the two theories. This study involves both field and lab research and includes a Ph.D. student and an undergraduate student. The research team will collect rocks from lava flows on an active volcano in Antarctica named Mount Erebus and measure the amounts of two rare isotopes: 36Cl and 3He. The age of eruption of the samples will be determined using a highly accurate method that does not depend on cosmic rays, called 40Ar/39Ar dating. The two cosmic-ray theories will be used to calculate the ages of the samples using the 36Cl and 3He concentrations and will then be compared to the ages calculated from the 40Ar/39Ar dating. The accurate cosmic-ray theory will be the one that gives the same ages as the 40Ar/39Ar dating. Identification of the accurate theory will enable use of the cosmogenic surface dating methods anywhere on earth. Technical Description: Nuclides produced by cosmic rays in rocks at the surface of the earth are widely used for Quaternary geochronology and geomorphic studies and their use is increasing every year. The recently completed CRONUS-Earth Project (Cosmic-Ray Produced Nuclides on Earth) has systematically evaluated the production rates and theoretical underpinnings of cosmogenic nuclides. However, the CRONUS-Earth Project was not able to discriminate between the two leading theoretical approaches: the original Lal model (St) and the new Lifton-Sato-Dunai model (LSD). Mathematical models used to scale the production of the nuclides as a function of location on the earth, elevation, and magnetic field configuration are an essential component of this dating method. The inability to distinguish between the two models was because the predicted production rates did not differ sufficiently at the location of the calibration sites. The cosmogenic-nuclide production rates that are predicted by the two models differ significantly from each other at Erebus volcano, Antarctica. Mount Erebus is therefore an excellent site for testing which production model best describes actual cosmogenic-nuclide production variations over the globe. The research team recently measured 3He and 36Cl in mineral separates extracted from Erebus lava flows. The exposure ages for each nuclide were reproducible within each flow (~2% standard deviation) and in very good agreement between the 3He and the 36Cl ages. However, the ages calculated by the St and LSD scaling methods differ by ~15-25% due to the sensitivity of the production rate to the scaling at this latitude and elevation. These results lend confidence that Erebus qualifies as a suitable high- latitude/high-elevation calibration site. The remaining component that is still lacking is accurate and reliable independent (i.e., non-cosmogenic) ages, however, published 40Ar/39Ar ages are too imprecise and typically biased to older ages due to excess argon contained in melt inclusions. The research team\u0027s new 40Ar/39Ar data show that previous problems with Erebus anorthoclase geochronology are now overcome with modern mass spectrometry and better sample preparation. This indicates a high likelihood of success for this proposal in defining an accurate global scaling model. Although encouraging, much remains to be accomplished. This project will sample lava flows over 3 km in elevation and determine their 40Ar/39Ar and exposure ages. These combined data will discriminate between the two scaling methods, resulting in a preferred scaling model for global cosmogenic geochronology. The LSD method contains two sub-methods, the \u0027plain\u0027 LSD scales all nuclides the same, whereas LSDn scales each nuclide individually. The project can discriminate between these models using 3He and 36Cl data from lava flows at different elevations, because the first model predicts that the production ratio for these two nuclides will be invariant with elevation and the second that there should be ~10% difference over the range of elevations to be sampled. Finally, the project will provide a local, finite-age calibration site for cosmogenic-nuclide investigations in Antarctica.", "east": 167.75, "geometry": "POINT(166.95999999999998 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "AGE DETERMINATIONS; Mount Erebus; VOLCANO", "locations": "Mount Erebus", "north": -77.3, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Phillips, Fred; Kyle, Philip; Heizler, Matthew T", "platforms": null, "repositories": null, "science_programs": null, "south": -77.7, "title": "A Test of Global and Antarctic Models for Cosmogenic-nuclide Production Rates using High-precision Dating of 40Ar/39Ar Lava Flows from Mount Erebus", "uid": "p0010397", "west": 166.17}, {"awards": "1643961 Anandakrishnan, Sridhar", "bounds_geometry": "POLYGON((-80 -83,-79.8 -83,-79.6 -83,-79.4 -83,-79.2 -83,-79 -83,-78.8 -83,-78.6 -83,-78.4 -83,-78.2 -83,-78 -83,-78 -83.2,-78 -83.4,-78 -83.6,-78 -83.8,-78 -84,-78 -84.2,-78 -84.4,-78 -84.6,-78 -84.8,-78 -85,-78.2 -85,-78.4 -85,-78.6 -85,-78.8 -85,-79 -85,-79.2 -85,-79.4 -85,-79.6 -85,-79.8 -85,-80 -85,-80 -84.8,-80 -84.6,-80 -84.4,-80 -84.2,-80 -84,-80 -83.8,-80 -83.6,-80 -83.4,-80 -83.2,-80 -83))", "dataset_titles": "Rutford Ice Stream short period data", "datasets": [{"dataset_uid": "200336", "doi": "https://doi.org/10.7914/SN/5B_2018", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Rutford Ice Stream short period data", "url": "http://fdsn.adc1.iris.edu/networks/detail/5B_2018/"}], "date_created": "Wed, 16 Nov 2022 00:00:00 GMT", "description": "Anandakrishnan/1643961 This award supports a project to study conditions under the Rutford Ice Stream, a large glacier that flows from the interior of the West Antarctic Ice Sheet to the Filchner Ronne Ice Shelf and then on to the ocean. The speed and volume of ice delivered to the ocean by this and similar glaciers is central to the question of sea-level change in the coming decades: if the volume of ice carried by Rutford to the ocean increases, then it will contribute to a rise in sea level. Numerical models of glacier flow that are used to forecast future conditions must include a component that accounts for the sliding of the ice over its bed. The sliding process is poorly modeled because of lack of detailed information about the bottom of glaciers, leading to increased uncertainty in the ice-flow models. Data from this project will provide such information. During this project, in collaboration with researchers at the British Antarctic Survey, a detailed survey of the properties of the bed of Rutford Ice Stream will be carried out. These surveys include using seismic instruments (which are sensitive to naturally occurring earthquakes within glaciers--called icequakes) to monitor the distribution of those icequakes at the bed. The locations, size, and timing of icequakes are controlled by the properties of the bed such as porosity, water pressure, and stress. As part of this project, a hole will be drilled to the bed of the glacier to monitor water pressures and to extract a sample of the basal material. By comparing the pressure variations with icequake production, the properties of the basal material over a large area can be better determined. Those results will aid in the application of numerical models by informing their description of the sliding process. This award requires field work in Antarctica. 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": -78.0, "geometry": "POINT(-79 -84)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; Seismicity; Ice Dynamic; Rutford Ice Stream", "locations": "Rutford Ice Stream", "north": -83.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Anandakrishnan, Sridhar", "platforms": null, "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -85.0, "title": "Rutford Ice Stream Cooperative Research Program with British Antarctic Survey", "uid": "p0010392", "west": -80.0}, {"awards": "2135695 Emslie, Steven; 2135696 Polito, Michael", "bounds_geometry": "POLYGON((-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70.8,-180 -71.6,-180 -72.4,-180 -73.2,-180 -74,-180 -74.8,-180 -75.6,-180 -76.4,-180 -77.2,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -77.2,160 -76.4,160 -75.6,160 -74.8,160 -74,160 -73.2,160 -72.4,160 -71.6,160 -70.8,160 -70,162 -70,164 -70,166 -70,168 -70,170 -70,172 -70,174 -70,176 -70,178 -70,-180 -70))", "dataset_titles": "Stable isotopes of Adelie Penguin chick bone collagen", "datasets": [{"dataset_uid": "601913", "doi": "10.15784/601913", "keywords": "Adelie Penguin; Antarctica; Cryosphere; Foraging; Polynya; Pygoscelis Adeliae; Ross Sea; Stable Isotopes", "people": "Powers, Shannon; Emslie, Steven D.; Reaves, Megan", "repository": "USAP-DC", "science_program": null, "title": "Stable isotopes of Adelie Penguin chick bone collagen", "url": "https://www.usap-dc.org/view/dataset/601913"}], "date_created": "Fri, 28 Oct 2022 00:00:00 GMT", "description": "The Ad\u00e9lie penguin (Pygoscelis adeliae) is the most abundant penguin in Antarctica, though its populations are currently facing threats from climate change, loss of sea ice habitat and food supplies. In the Ross Sea region, the cold, dry environment has allowed preservation of Ad\u00e9lie penguin bones, feathers, eggshell and even mummified remains, at active and abandoned colonies that date from before the Last Glacial Maximum (more than 45,000 years ago) to the present. A warming period at 4,000-2,000 years ago, known as the penguin \u2018optimum\u2019, reduced sea ice extent and allowed this species to access and reproduce in the southern Ross Sea. This coastline likely will be reoccupied in the future as marine conditions change with current warming trends. This project will investigate ecological responses in diet and foraging behavior of the Ad\u00e9lie penguin using well-preserved bones and other tissues that date from before, during and after the penguin \u2018optimum\u2019. The Principal investigators will collect and analyze bones, feathers and eggshells from colonies in the Ross Sea to determine changes in population size and feeding locations over millennia. Most of these colonies are associated with highly productive areas of open water surrounded by sea ice. Current warming trends are causing relatively rapid ecological responses by this species and some of the largest colonies in the Ross Sea are likely to be abandoned in the next 50 years from rising sea level. The recently established Ross Sea Marine Protected Area aims to protect Ad\u00e9lie penguins and their foraging grounds in this region from human impacts and knowledge on how this species has responded to climate change in the past will support this goal. This project benefits NSF\u2019s mission to expand fundamental knowledge of Antarctic systems, biota, and processes. In association with their research program, the Principal Investigators will create undergraduate opportunities for research-driven coursework, will design K-12 curriculum and assess the effectiveness of these activities. Two graduate students will be supported by this project to update and refine the curricula working with K-12 teachers. There is also training and partial support included for one doctorate, two master and eight undergraduate students. General public will be reached through social media and YouTube channel productions. A suite of three stable isotopes (carbon, nitrogen, and sulfur) will be analyzed in Adelie penguin bones and feathers from active and abandoned colonies to assess ecological shifts through time. Stable isotope analyses of carbon and nitrogen (\u03b413C and \u03b415N) are commonly used to investigate animal migration, foraging locations and diet, especially in marine species that can travel over great distances. Sulfur (\u03b434S) is not as commonly used but is increasingly being applied to refine and corroborate data obtained from carbon and nitrogen analyses. Collagen is one of the best tissues for these analyses as it is abundant in bone, preserves well, and can be easily extracted for analysis. Using these three isotopes from collagen, ancient and modern penguin colonies will be investigated in the southern, central and northern Ross Sea to determine changes in populations and foraging locations over millennia. Most of these colonies are associated with one of three polynyas in the Ross Sea. This study will be the first of its kind to apply multiple stable isotope analyses to investigate a living species of seabird over millennia in a region where it still exists today. Results from this project will also inform management on best practices for Adelie penguin conservation affected by climate change. 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(170 -74)", "instruments": null, "is_usap_dc": true, "keywords": "Climate Change; Adelie Penguin; Foraging Ecology; Ross Sea; PENGUINS; Holocene; Stable Isotopes", "locations": "Ross Sea", "north": -70.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Lane, Chad S; Polito, Michael", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Using Multiple Stable Isotopes to Investigate Middle to Late Holocene Ecological Responses by Adelie Penguins in the Ross Sea", "uid": "p0010388", "west": 160.0}, {"awards": "1644118 Dunbar, Robert", "bounds_geometry": "POLYGON((-108 -73,-107.3 -73,-106.6 -73,-105.9 -73,-105.2 -73,-104.5 -73,-103.8 -73,-103.1 -73,-102.4 -73,-101.7 -73,-101 -73,-101 -73.3,-101 -73.6,-101 -73.9,-101 -74.2,-101 -74.5,-101 -74.8,-101 -75.1,-101 -75.4,-101 -75.7,-101 -76,-101.7 -76,-102.4 -76,-103.1 -76,-103.8 -76,-104.5 -76,-105.2 -76,-105.9 -76,-106.6 -76,-107.3 -76,-108 -76,-108 -75.7,-108 -75.4,-108 -75.1,-108 -74.8,-108 -74.5,-108 -74.2,-108 -73.9,-108 -73.6,-108 -73.3,-108 -73))", "dataset_titles": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020", "datasets": [{"dataset_uid": "601611", "doi": "10.15784/601611", "keywords": "Amundsen Sea; Antarctica; Chemistry:Water; CTD; D18O; NBP0001; NBP0702; NBP0901; NBP1901; NBP2002; Oceans; Oxygen Isotope; R/v Nathaniel B. Palmer; Seawater Isotope; Southern Ocean", "people": "Hennig, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020", "url": "https://www.usap-dc.org/view/dataset/601611"}], "date_created": "Wed, 21 Sep 2022 00:00:00 GMT", "description": "Estimating Antarctic ice sheet growth or loss is important to predicting future sea level rise. Such estimates rely on field measurements or remotely sensed based observations of the ice sheet surface, ice margins, and or ice shelves. This work examines the introduction of freshwater into the ocean to surrounding Antarctica to track meltwater from continental ice. Polar ice is depleted in two stable isotopes, 18O and D, deuterium, relative to Southern Ocean seawater and precipitation. Measurements of seawater isotopic composition in conjunction with precise observations of seawater temperature and salinity, will permit discrimination of freshwater derived from melting glacial ice from that derived from regional precipitation or sea ice melt. This research describes an accepted method for determining rates and locations of meltwater entering the oceans from polar ice sheets. As isotopic and salinity perturbations are cumulative in many Antarctic coastal seas, the method allows for the detection of any marked acceleration in meltwater introduction in specific regions, using samples collected and analyzed over a period of years to decades. Impact of the project derives from use of an independent method capable of constraining knowledge about current ice sheet melt rates, their stability and potential impact on sea level rise. The project allows for sample collection taken from foreign vessels of opportunity sailing in Antarctic waters, and subsequent sharing and interpretation of data. Research partners include the U.S., Korea, China, New Zealand, the United Kingdom, and Germany. Participating collaborators will collect seawater samples for isotopic and salinity analysis at Stanford University. USAP cruises will concentrate on sampling the Ross Sea, and the West Antarctic. The work plan includes interpretation of isotopic data using box model and mixing curve analyses as well as using isotope enabled ROMS (Regional Ocean Modeling System) models. The broader impacts of the research will include development of an educational module that illustrates the scientific method and how ocean observations help society understand how Earth is changing.", "east": -101.0, "geometry": "POINT(-104.5 -74.5)", "instruments": null, "is_usap_dc": true, "keywords": "Stable Isotopes; WATER TEMPERATURE; SALINITY; Oxygen Isotope; Meltwater Inventory; Pine Island Bay; OCEAN CHEMISTRY", "locations": "Pine Island Bay", "north": -73.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Dunbar, Robert", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.0, "title": "Estimation of Antarctic Ice Melt using Stable Isotopic Analyses of Seawater", "uid": "p0010380", "west": -108.0}, {"awards": "2218402 Fegyveresi, John", "bounds_geometry": "POLYGON((-115 -85.5,-113.5 -85.5,-112 -85.5,-110.5 -85.5,-109 -85.5,-107.5 -85.5,-106 -85.5,-104.5 -85.5,-103 -85.5,-101.5 -85.5,-100 -85.5,-100 -85.65,-100 -85.8,-100 -85.95,-100 -86.1,-100 -86.25,-100 -86.4,-100 -86.55,-100 -86.7,-100 -86.85,-100 -87,-101.5 -87,-103 -87,-104.5 -87,-106 -87,-107.5 -87,-109 -87,-110.5 -87,-112 -87,-113.5 -87,-115 -87,-115 -86.85,-115 -86.7,-115 -86.55,-115 -86.4,-115 -86.25,-115 -86.1,-115 -85.95,-115 -85.8,-115 -85.65,-115 -85.5))", "dataset_titles": "Multi-Site Brittle Ice Data and Measurements", "datasets": [{"dataset_uid": "601786", "doi": "10.15784/601786", "keywords": "Antarctica; Brittle Ice; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Glaciology; Ice Core; Ice Core Records; Ice Core Records; Physical Properties; Simple Dome; Siple Dome; South Pole; SPICEcore; Subgrain Boundaries; WAIS Divide", "people": "Fegyveresi, John; Barnett, Samantha", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Multi-Site Brittle Ice Data and Measurements", "url": "https://www.usap-dc.org/view/dataset/601786"}], "date_created": "Mon, 19 Sep 2022 00:00:00 GMT", "description": "Ice cores are a vital source of information about past climate. Research that utilizes ice cores benefits from an undamaged ice-core record. There is often a zone within ice sheets where the ice is brittle upon extraction in a core. Brittle-ice behavior occurs when the rapid decompression of the core as it is being extracted from the ice-sheet results in extensive fracturing. Ice from this zone can compromise the undamaged record. This project seeks to improve our understanding of the mechanisms involved in brittle-ice behavior and onset, with the goal of helping to guide field-site operations, core handling preparation, and planned laboratory measurement techniques for future ice-coring projects, including the upcoming work at Hercules Dome. This project requires no field work, as it will use existing observations and existing ice cores to gain an understanding of brittle ice. This is a high-risk and timely proposal that is early-concept and exploratory in nature, making it appropriate for the EAGER solicitation. The project will support an early-career researcher and provide training for a master\u2019s student who is a woman. And, finally, the project will develop educational and outreach materials for graduate and undergraduate courses and elementary schools. This project will examine and catalog brittle ice from several existing ice-core samples to specifically assess various ice physical properties affecting brittleness potential, including bubble size and number-density, ice fabric, grain statistics, fracture characteristics, and the location and properties of grain and subgrain boundaries. End members of this sample assessment have been identified and include Siple Dome, which exhibited major brittle behavior and damage, and South Pole ice core, which exhibited very-minor brittle behavior and almost no damage. Output datasets will include calibrated relationships for bubble number-density, mean grain and bubble sizes, subgrain prevalence and orientation, and a usable indicator for estimating brittle-ice onset and magnitude. There is an immediate applicability of results from this effort for the Hercules Dome drilling 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": -100.0, "geometry": "POINT(-107.5 -86.25)", "instruments": null, "is_usap_dc": true, "keywords": "Hercules Dome Ice Core; West Antarctica; Grain Statistics; LABORATORY; Ice Core; ICE SHEETS; Physical Properties; Brittle Ice; C-Axis Fabric; Bubble; ICE CORE RECORDS", "locations": "West Antarctica", "north": -85.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fegyveresi, John", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Hercules Dome Ice Core", "south": -87.0, "title": "EAGER: Constraining the Expected Brittle-ice Behavior for the Hercules Dome Ice-core Site.", "uid": "p0010378", "west": -115.0}, {"awards": "1853377 Shero, Michelle", "bounds_geometry": "POLYGON((162 -76,162.6 -76,163.2 -76,163.8 -76,164.4 -76,165 -76,165.6 -76,166.2 -76,166.8 -76,167.4 -76,168 -76,168 -76.2,168 -76.4,168 -76.6,168 -76.8,168 -77,168 -77.2,168 -77.4,168 -77.6,168 -77.8,168 -78,167.4 -78,166.8 -78,166.2 -78,165.6 -78,165 -78,164.4 -78,163.8 -78,163.2 -78,162.6 -78,162 -78,162 -77.8,162 -77.6,162 -77.4,162 -77.2,162 -77,162 -76.8,162 -76.6,162 -76.4,162 -76.2,162 -76))", "dataset_titles": "Weddell seal dive behavior and rhythmicity from 2010-2012 in the Ross Sea; Weddell seal iron dynamics and oxygen stores across lactation", "datasets": [{"dataset_uid": "601587", "doi": "10.15784/601587", "keywords": "Aerobic; Antarctica; Dive Capacity; Iron; McMurdo Sound; Weddell Seal", "people": "Shero, Michelle", "repository": "USAP-DC", "science_program": null, "title": "Weddell seal iron dynamics and oxygen stores across lactation", "url": "https://www.usap-dc.org/view/dataset/601587"}, {"dataset_uid": "601835", "doi": "10.15784/601835", "keywords": "Aerobic; Antarctica; Cryosphere; Weddell Seal", "people": "Shero, Michelle", "repository": "USAP-DC", "science_program": null, "title": "Weddell seal dive behavior and rhythmicity from 2010-2012 in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601835"}], "date_created": "Tue, 09 Aug 2022 00:00:00 GMT", "description": "Within any population, some individuals perform better than others. These individuals may survive longer or produce more offspring. Weddell seals in Erebus Bay, Antarctica, provide an unparalleled opportunity to investigate how an animal\u0027s physiology, behavior, and genetic make-up contribute to lifetime reproductive success because they have been the subject of a long-term population monitoring study and are easily accessible during their reproductive season. This project will distinguish key differences in energy allocation, reproductive timing, and dive capacities between female Weddell seals with a history of frequently producing pups (\"high-quality\" group), versus females that have produced pups only infrequently (\"low-quality\" group). For each group of females, physiology and behavior during the nursing period will be analyzed to assess whether investments influence their probability of reproducing the following year. Whole genomes will be compared between groups to identify underlying genes that govern reproductive success and population stability in a long-lived mammal. This collaborative project will provide research opportunities and training to several undergraduate and graduate students at the three participating institutions. Results will be broadly disseminated through presentations and peer-reviewed publications, and to students via an extensive public outreach collaboration with museum programming, curriculum-aligned science lessons, and pedagogy training. Within any wild animal population there is substantial heterogeneity in reproductive rates and animal fitness. Not all individuals contribute to the population equally; some are able to produce more offspring than others and thus are considered to be of higher quality. This study aims to distinguish which physiological mechanisms (energy dynamics, aerobic capacity, and fertility) and underlying genetic factors make some Weddell seal females particularly successful at producing pups year after year, while others produce far fewer pups than the population average. In this project, an Organismal Energetics approach will identify key differences between high- and low-quality females in how they balance current and future reproductive success by tracking lactation costs, midsummer foraging success and pregnancy rates, and overwinter foraging patterns and live births the next year. Repeated sampling of individuals\u0027 physiological status (body composition, endocrinology, ovulation and pregnancy timing), will be paired with a whole-genome sequencing study. The second component of this study uses a Genome to Phenome approach to better understand how genetic differences between high- and low-quality females directly correspond to functional differences in transcription, translation, and ultimately phenotype. This component will contribute to the functional analysis and annotation of the Weddell seal genome. In combination, this project will make strides towards distinguishing the roles that plastic (physiological, behavioral) and fixed (genetic) factors play in complex, multifaceted traits such as fitness in a long-lived wild mammal. The project partners with established programs to implement extensive educational and outreach activities that will ensure wide dissemination to educators, students, and the public. It will contribute to a marine mammal exhibit at the Pink Palace Museum, and a PolarTREC science educator will participate in field work in Antarctica. This award is co-funded by the GEO-OPP-Antarctic Organisms and Ecosystems Program, BIO-IOS-Physiological Mechanisms and Biomechanics Program, and the Established Program to Stimulate Competitive Research (EPSCoR). 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": 168.0, "geometry": "POINT(165 -77)", "instruments": null, "is_usap_dc": true, "keywords": "McMurdo; MAMMALS", "locations": "McMurdo", "north": -76.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Shero, Michelle; Hindle, Allyson; Burns, Jennifer; Briggs, Brandon", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Physiological and Genetic Correlates of Reproductive Success in High- versus Low-Quality Weddell seals", "uid": "p0010369", "west": 162.0}, {"awards": "1744649 Christianson, Knut", "bounds_geometry": "POLYGON((-120 -85.5,-117.5 -85.5,-115 -85.5,-112.5 -85.5,-110 -85.5,-107.5 -85.5,-105 -85.5,-102.5 -85.5,-100 -85.5,-97.5 -85.5,-95 -85.5,-95 -85.62,-95 -85.74,-95 -85.86,-95 -85.98,-95 -86.1,-95 -86.22,-95 -86.34,-95 -86.46000000000001,-95 -86.58,-95 -86.7,-97.5 -86.7,-100 -86.7,-102.5 -86.7,-105 -86.7,-107.5 -86.7,-110 -86.7,-112.5 -86.7,-115 -86.7,-117.5 -86.7,-120 -86.7,-120 -86.58,-120 -86.46000000000001,-120 -86.34,-120 -86.22,-120 -86.1,-120 -85.98,-120 -85.86,-120 -85.74,-120 -85.62,-120 -85.5))", "dataset_titles": "Hercules Dome ApRES Data; Hercules Dome High-Frequency Impulse Ice-Penetrating Radar Data; Hercules Dome Ice-Penetrating Radar Swath Topographies; Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets; ITASE Impulse Radar Hercules Dome to South Pole", "datasets": [{"dataset_uid": "601711", "doi": "10.15784/601711", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Hercules Dome; Ice Penetrating Radar; Snow/ice; Snow/Ice", "people": "Paden, John; Holschuh, Nicholas; Hoffman, Andrew; Christianson, Knut", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "Hercules Dome Ice-Penetrating Radar Swath Topographies", "url": "https://www.usap-dc.org/view/dataset/601711"}, {"dataset_uid": "601606", "doi": "10.15784/601606", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Ice Penetrating Radar; Snow/ice; Snow/Ice", "people": "Christianson, Knut", "repository": "USAP-DC", "science_program": null, "title": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets", "url": "https://www.usap-dc.org/view/dataset/601606"}, {"dataset_uid": "601712", "doi": "10.15784/601712", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Hercules Dome; Ice Penetrating Radar; Snow/ice; Snow/Ice", "people": "Welch, Brian; Jacobel, Robert; Hoffman, Andrew; Christianson, Knut", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "ITASE Impulse Radar Hercules Dome to South Pole", "url": "https://www.usap-dc.org/view/dataset/601712"}, {"dataset_uid": "601739", "doi": "10.15784/601739", "keywords": "Antarctica; Apres; Crystal Orientation Fabric; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hercules Dome; Ice Dynamic; Ice Penetrating Radar; Radar Interferometry; Radar Polarimetry", "people": "Horlings, Annika; Hoffman, Andrew; Hills, Benjamin; Fudge, Tyler J; Erwin, Emma; Steig, Eric J.; Christianson, Knut; Holschuh, Nicholas", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "Hercules Dome ApRES Data", "url": "https://www.usap-dc.org/view/dataset/601739"}, {"dataset_uid": "601710", "doi": "10.15784/601710", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Hercules Dome; Ice Penetrating Radar; Snow/ice; Snow/Ice", "people": "Hills, Benjamin; Hoffman, Andrew; Christianson, Knut; O\u0027Connor, Gemma; Horlings, Annika; Holschuh, Nicholas; Christian, John", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "Hercules Dome High-Frequency Impulse Ice-Penetrating Radar Data", "url": "https://www.usap-dc.org/view/dataset/601710"}], "date_created": "Tue, 02 Aug 2022 00:00:00 GMT", "description": "The response of the Antarctic ice sheet to climate change is a central issue in projecting global sea-level rise. While much attention is focused on the ongoing rapid changes at the coastal margin of the West Antarctic Ice Sheet, obtaining records of past ice-sheet and climate change is the only way to constrain how an ice sheet changes over millennial timescales. Whether the West Antarctic Ice Sheet collapsed during the last interglacial period (~130,000 to 116,000 years ago), when temperatures were slightly warmer than today, remains a major unsolved problem in Antarctic glaciology. Hercules Dome is an ice divide located at the intersection of the East Antarctic and West Antarctic ice sheets. It is ideally situated to record the glaciological and climatic effects of changes in the West Antarctic Ice Sheet. This project will establish whether Hercules Dome experienced major changes in flow due to changes in the elevation of the two ice sheets. The project will also ascertain whether Hercules Domes is a suitable site from which to recover climate records from the last interglacial period. These records could be used to determine whether the West Antarctic Ice Sheet collapsed during that period. The project will support two early-career researchers and train students at the University of Washington. Results will be communicated through outreach programs in coordination the Ice Drilling Project Office, the University of Washington\u0027s annual Polar Science Weekend in Seattle, and art-science collaboration. This project will develop a history of ice dynamics at the intersection of the East and West Antarctic ice sheets, and ascertain whether the site is suitable for a deep ice-coring operation. Ice divides provide a unique opportunity to assess the stability of past ice flow. The low deviatoric stresses and non-linearity of ice flow causes an arch (a \"Raymond Bump\") in the internal layers beneath a stable ice divide. This information can be used to determine the duration of steady ice flow. Due to the slow horizontal ice-flow velocities, ice divides also preserve old ice with internal layering that reflects past flow conditions caused by divide migration. Hercules Dome is an ice divide that is well positioned to retain information of past variations in the geometry of both the East and West Antarctic Ice Sheets. This dome is also the most promising location at which to recover an ice core that can be used to determine whether the West Antarctic Ice Sheet collapsed during the last interglacial period. Limited ice-penetrating radar data collected along a previous scientific surface traverse indicate well-preserved englacial stratigraphy and evidence suggestive of a Raymond Bump, but the previous survey was not sufficiently extensive to allow thorough characterization or determination of past changes in ice dynamics. This project will conduct a dedicated survey to map the englacial stratigraphy and subglacial topography as well as basal properties at Hercules Dome. The project will use ground-based ice-penetrating radar to 1) image internal layers and the ice-sheet basal interface, 2) accurately measure englacial attenuation, and 3) determine englacial vertical strain rates. The radar data will be combined with GPS observations for detailed topography and surface velocities and ice-flow modeling to constrain the basal characteristics and the history of past ice flow. 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": -95.0, "geometry": "POINT(-107.5 -86.1)", "instruments": null, "is_usap_dc": true, "keywords": "West Antarctica; ICE DEPTH/THICKNESS; East Antarctica", "locations": "West Antarctica; East Antarctica", "north": -85.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Christianson, Knut; Hoffman, Andrew; Holschuh, Nicholas", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -86.7, "title": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets", "uid": "p0010359", "west": -120.0}, {"awards": "2114502 Tinto, Kirsteen", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 19 Jul 2022 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). An important part of understanding future climate change is predicting changes in how fast the ice in Antarctica is moving. If ice flows more quickly towards the ocean, it will have a direct impact on sea level rise. One of the things that can influence the ice flow is the type of rock below the ice coverage in Antarctica. Sedimentary basins are large regions where sedimentary rocks accumulated in the past, often under ancient seas. It has been observed that where there are sediments below the ice, the ice can flow faster. This project seeks to understand what is below the ice and how the underlying rock influences the ice flow. Is it hard, crystalline rock? Is it a sedimentary basin? What is the relationship between sediments and ice flow? The answers to these questions will be addressed by using a combination of available data and geophysical methods. Information from well-known rock-types will be used to train the computer to recognize these features by using an application of artificial intelligence known as machine learning, which will help the characterization and identification of unknown sedimentary basins beneath the ice. The results of this project will be disseminated to a broad audience by holding workshops for teacher and students to explain our findings under the ice and to introduce the machine learning technique. Open-source codes used during this project will be made available for use in higher-level classrooms as well as in further studies. To date, no comprehensive distribution of onshore and offshore sedimentary basins over Antarctica has been developed. A combination of large-scale datasets will be used to characterize known basins and identify new sedimentary basins to produce the first continent-wide mapping of sedimentary basins and provide improved basal parametrizations conditions that have the potential to support more realistic ice sheet models. Available geophysical compilations of data and the location of well-known sedimentary basins will be used to apply an ensemble machine learning algorithm. The machine learning algorithm will learn complex relationships by voting among a collection of randomized decision trees. The gravity signal related to sedimentary basins known from other (e.g. seismic) techniques will be evaluated and unknown basins from aerogravity data regression analyses will be proposed by calculating a gravity residual that reflects density inhomogeneities. The gravimetric sedimentary basins identified from the regression analyses will be compared with an independent method of identifying sedimentary distribution, the Werner deconvolution method of estimating depth to magnetic sources. The hypothesis, which is sedimentary basins are correlated to fast ice flow behavior, will be tested by comparing the location of the sedimentary basins with locations of high ice flow by using available ice velocity observations. A relationship between sedimentary basins and ice streams will be defined qualitatively and quantitatively, aiming to evaluate if there are ice streams where no sedimentary basins are reported, or sedimentary basins with no ice streams related. The findings of these project can confirm if the presence of abundant sediments is a pre-requisite for ice streaming. Analyzing previously known sedimentary basins and identifying new ones in Antarctica is central to evaluating the influence of subglacial sediments on the ice sheet flow. 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": "GRAVITY ANOMALIES; ICE SHEETS; Antarctica", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Constantino, Renata", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Pan-Antarctic Assessment of Sedimentary Basins and the Onset of Streaming Ice Flow from Machine Learning and Aerogravity Regression Analyses", "uid": "p0010351", "west": -180.0}, {"awards": "2138277 Gallagher, Katherine", "bounds_geometry": "POLYGON((-78 -62,-76.2 -62,-74.4 -62,-72.6 -62,-70.8 -62,-69 -62,-67.2 -62,-65.4 -62,-63.6 -62,-61.8 -62,-60 -62,-60 -63,-60 -64,-60 -65,-60 -66,-60 -67,-60 -68,-60 -69,-60 -70,-60 -71,-60 -72,-61.8 -72,-63.6 -72,-65.4 -72,-67.2 -72,-69 -72,-70.8 -72,-72.6 -72,-74.4 -72,-76.2 -72,-78 -72,-78 -71,-78 -70,-78 -69,-78 -68,-78 -67,-78 -66,-78 -65,-78 -64,-78 -63,-78 -62))", "dataset_titles": "Current velocity and direction data from Regional Ocean Modeling System simulations (2006-2007 \u0026 2010-2011); Current velocity and direction data from Regional Ocean Modeling System simulations (2008-2009 \u0026 2018-2019); Passive particle trajectories from Regional Ocean Modeling System simulations 2008-2009 \u0026 2018-2019; Simulated krill trajectory data from Regional Ocean Modeling System simulations 2006-2007 \u0026 2010-2011; Simulated krill trajectory data from Regional Ocean Modeling System simulations 2008-2009 \u0026 2018-2019; Simulated marine debris trajectories along the West Antarctic Peninsula in 2008-2009 and 2018-2019", "datasets": [{"dataset_uid": "601734", "doi": "10.15784/601734", "keywords": "Antarctica; Modeling; Regional Ocean Modeling System; West Antarctic Shelf", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Simulated marine debris trajectories along the West Antarctic Peninsula in 2008-2009 and 2018-2019", "url": "https://www.usap-dc.org/view/dataset/601734"}, {"dataset_uid": "601655", "doi": "10.15784/601655", "keywords": "Antarctica; Antarctic Krill; Model Data; Physical Oceanography; Regional Ocean Modeling System; ROMS; West Antarctic Shelf", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Simulated krill trajectory data from Regional Ocean Modeling System simulations 2008-2009 \u0026 2018-2019", "url": "https://www.usap-dc.org/view/dataset/601655"}, {"dataset_uid": "601682", "doi": "10.15784/601682", "keywords": "Antarctica; Physical Oceanography; Regional Ocean Modeling System; ROMS", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Passive particle trajectories from Regional Ocean Modeling System simulations 2008-2009 \u0026 2018-2019", "url": "https://www.usap-dc.org/view/dataset/601682"}, {"dataset_uid": "601656", "doi": "10.15784/601656", "keywords": "Antarctica; Model Data; Ocean Currents; Physical Oceanography; Regional Ocean Modeling System; ROMS; West Antarctic Shelf", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Current velocity and direction data from Regional Ocean Modeling System simulations (2008-2009 \u0026 2018-2019)", "url": "https://www.usap-dc.org/view/dataset/601656"}, {"dataset_uid": "601779", "doi": "10.15784/601779", "keywords": "Antarctica; Cryosphere; Model Data; Ocean Currents; Physical Oceanography; Regional Ocean Modeling System; ROMS; West Antarctic Shelf", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Current velocity and direction data from Regional Ocean Modeling System simulations (2006-2007 \u0026 2010-2011)", "url": "https://www.usap-dc.org/view/dataset/601779"}, {"dataset_uid": "601780", "doi": "10.15784/601780", "keywords": "Antarctica; Antarctic Krill; Cryosphere; Model Data; Physical Oceanography; Regional Ocean Modeling System; ROMS; West Antarctic Shelf", "people": "Gallagher, Katherine", "repository": "USAP-DC", "science_program": null, "title": "Simulated krill trajectory data from Regional Ocean Modeling System simulations 2006-2007 \u0026 2010-2011", "url": "https://www.usap-dc.org/view/dataset/601780"}], "date_created": "Tue, 19 Jul 2022 00:00:00 GMT", "description": "Pygoscelis penguins are central place foragers during the summer while they raise their chicks. They leave and return to the same colony location after hunting for food and rely on the availability of Antarctic krill, their primary food source. This research focuses on whether penguin diets and colony location reflect the retention of prey around and near colonies on the West Antarctic Peninsula. Eddies and other oceanographic processes may facilitate prey retention at certain locations, driving penguin colony establishment and success. This project hypothesizes that Pygoscelis penguin diets will be composed of more Antarctic krill (Euphausia superba) when local prey retention is high, possibly due to subsurface eddies. This hypothesis will be tested using satellite-based estimates of Pygoscelis penguin diet composition using multispectral sensor data to estimate nitrogen values and infer trophic level. Prey retention will be calculated along the peninsula using the Regional Ocean Modeling System (ROMS). Simulated particles and diel vertical migration will be used to mimic krill behavior. These particles can be experimentally seeded across multiple depths in multiple years to assess residence times in the system. Using penguin colony data from the Mapping Application for Penguin Populations and Projected Dynamics (MAPPPD), the PI will correlate diet and retention metrics to local penguin colony growth and persistence and build a predictive model of where colonies may form in the future. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -60.0, "geometry": "POINT(-69 -67)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; PENGUINS; SPECIES/POPULATION INTERACTIONS; OCEAN CURRENTS", "locations": "Antarctic Peninsula", "north": -62.0, "nsf_funding_programs": "Post Doc/Travel", "paleo_time": null, "persons": "Gallagher, Katherine", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.0, "title": "OPP-PRF Pygoscelis Penguin Response to Potential Prey Retention along the West Antarctic Peninsula", "uid": "p0010349", "west": -78.0}, {"awards": "1744885 Moline, Mark", "bounds_geometry": "POLYGON((-64.643 -64.703149,-64.5388975 -64.703149,-64.43479500000001 -64.703149,-64.3306925 -64.703149,-64.22659 -64.703149,-64.1224875 -64.703149,-64.018385 -64.703149,-63.9142825 -64.703149,-63.81018 -64.703149,-63.706077500000006 -64.703149,-63.601975 -64.703149,-63.601975 -64.7258003,-63.601975 -64.7484516,-63.601975 -64.77110289999999,-63.601975 -64.7937542,-63.601975 -64.8164055,-63.601975 -64.8390568,-63.601975 -64.86170809999999,-63.601975 -64.8843594,-63.601975 -64.9070107,-63.601975 -64.929662,-63.706077500000006 -64.929662,-63.81018 -64.929662,-63.9142825 -64.929662,-64.018385 -64.929662,-64.1224875 -64.929662,-64.22659 -64.929662,-64.3306925 -64.929662,-64.43479500000001 -64.929662,-64.5388975 -64.929662,-64.643 -64.929662,-64.643 -64.9070107,-64.643 -64.8843594,-64.643 -64.86170809999999,-64.643 -64.8390568,-64.643 -64.8164055,-64.643 -64.7937542,-64.643 -64.77110289999999,-64.643 -64.7484516,-64.643 -64.7258003,-64.643 -64.703149))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 18 Jul 2022 00:00:00 GMT", "description": "This research project will use specially designed autonomous underwater vehicles (AUVs) to investigate interactions between Adelie and Gentoo penguins (the predators) and their primary food source, Antarctic krill (prey). While it has long been known that penguins feed on krill, details about how they search for food and target individual prey items is less well understood. Krill aggregate in large swarms, and the size or the depth of these swarms may influence the feeding behavior of penguins. Similarly, penguin feeding behaviors may differ based on characteristics of the environment, krill swarms, and the presence of other prey and predator species. This project will use specialized smart AUVs to simultaneously collect high-resolution observations of penguins, their prey, and environmental conditions. Data will shed light on strategies used by penguins prove foraging success during the critical summer chick-rearing period. This will improve predictions of how penguin populations may respond to changing environmental conditions in the rapidly warming Western Antarctic Peninsula region. Greater understanding of how individual behaviors shape food web structure can also inform conservation and management efforts in other marine ecosystems. This project has a robust public education and outreach plan linked with the Birch and Monterey Bay Aquariums. Previous studies have shown that sub-mesoscale variability (1-10 km) in Antarctic krill densities and structure impact the foraging behavior of air-breathing predators. However, there is little understanding of how krill aggregation characteristics are linked to abundance on fine spatial scales, how these patterns are influenced by the habitat, or how prey characteristics influences the foraging behavior of predators. These data gaps remain because it is extremely challenging to collect detailed data on predators and prey simultaneously at the scale of an individual krill patch and single foraging event. Building on previously successful efforts, this project will integrate echosounders into autonomous underwater vehicles (AUVs), so that oceanographic variables and multi-frequency acoustic scattering from both prey and penguins can be collected simultaneously. This will allow for quantification of the environment at the scale of individual foraging events made by penguins during the critical 50+ day chick-rearing period. Work will be centered near Palmer Station, where long-term studies have provided significant insight into predator and prey population trends. The new data to be collected by this project will test hypotheses about how penguin prey selection and foraging behaviors are influenced by physical and biological features of their ocean habitat at extremely fine scale. By addressing the dynamic relationship between individual penguins, their prey, and habitat at the scale of individual foraging events, this study will begin to reveal the important processes regulating resource availability and identify what makes this region a profitable foraging habitat and breeding location. 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": -63.601975, "geometry": "POINT(-64.1224875 -64.8164055)", "instruments": null, "is_usap_dc": true, "keywords": "COASTAL; COMMUNITY DYNAMICS; ECOSYSTEM FUNCTIONS; SPECIES/POPULATION INTERACTIONS; Palmer Station; MICROALGAE; PENGUINS; ANIMALS/INVERTEBRATES", "locations": "Palmer Station", "north": -64.703149, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Moline, Mark; Benoit-Bird, Kelly; Cimino, Megan", "platforms": null, "repositories": null, "science_programs": null, "south": -64.929662, "title": "Collaborative Research: Linking Predator Behavior and Resource Distributions: Penguin-directed Exploration of an Ecological Hotspot", "uid": "p0010347", "west": -64.643}, {"awards": "1745023 Hennon, Tyler; 1745009 Kohut, Josh; 1745011 Klinck, John; 1745081 Bernard, Kim; 1744884 Oliver, Matthew; 1745018 Fraser, William", "bounds_geometry": "POLYGON((-75 -60,-73 -60,-71 -60,-69 -60,-67 -60,-65 -60,-63 -60,-61 -60,-59 -60,-57 -60,-55 -60,-55 -61,-55 -62,-55 -63,-55 -64,-55 -65,-55 -66,-55 -67,-55 -68,-55 -69,-55 -70,-57 -70,-59 -70,-61 -70,-63 -70,-65 -70,-67 -70,-69 -70,-71 -70,-73 -70,-75 -70,-75 -69,-75 -68,-75 -67,-75 -66,-75 -65,-75 -64,-75 -63,-75 -62,-75 -61,-75 -60))", "dataset_titles": "Antarctic ACROBAT data; CTD Data from IFCB Sampling; Finite Time Lyapunov Exponent Results, Calculated from High Frequency Radar Observed Surface Currents; High Frequency Radar, Palmer Deep; IFCB Image Data; Relative Particle Density; SWARM AMLR moorings - acoustic data; SWARM Glider Data near Palmer Deep; WAP model float data; Winds from Joubin and Wauwerman Islands", "datasets": [{"dataset_uid": "200396", "doi": "10.26008/1912/bco-dmo.867442.2", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "WAP model float data", "url": "https://www.bco-dmo.org/dataset/867442"}, {"dataset_uid": "200390", "doi": "10.26008/1912/bco-dmo.865030.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "CTD Data from IFCB Sampling", "url": "https://www.bco-dmo.org/dataset/865030"}, {"dataset_uid": "200398", "doi": "", "keywords": null, "people": null, "repository": "IOOS Glider DAAC", "science_program": null, "title": "SWARM Glider Data near Palmer Deep", "url": "https://gliders.ioos.us/erddap/search/index.html?page=1\u0026itemsPerPage=1000\u0026searchFor=swarm"}, {"dataset_uid": "200392", "doi": "10.26008/1912/bco-dmo.917884.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "High Frequency Radar, Palmer Deep", "url": "https://www.bco-dmo.org/dataset/917884"}, {"dataset_uid": "200397", "doi": "10.26008/1912/bco-dmo.865098.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Winds from Joubin and Wauwerman Islands", "url": "https://www.bco-dmo.org/dataset/865098"}, {"dataset_uid": "200394", "doi": "10.26008/1912/bco-dmo.917926.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Relative Particle Density", "url": "https://www.bco-dmo.org/dataset/917926"}, {"dataset_uid": "200393", "doi": "10.26008/1912/bco-dmo.865002.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "IFCB Image Data", "url": "https://www.bco-dmo.org/dataset/865002"}, {"dataset_uid": "200389", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Antarctic ACROBAT data", "url": "https://www.bco-dmo.org/dataset/916046"}, {"dataset_uid": "200391", "doi": "10.26008/1912/bco-dmo.917914.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Finite Time Lyapunov Exponent Results, Calculated from High Frequency Radar Observed Surface Currents", "url": "https://www.bco-dmo.org/dataset/917914"}, {"dataset_uid": "200395", "doi": "10.26008/1912/bco-dmo.872729.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "SWARM AMLR moorings - acoustic data", "url": "https://www.bco-dmo.org/dataset/872729"}], "date_created": "Tue, 05 Jul 2022 00:00:00 GMT", "description": "Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function. To understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots. 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": -55.0, "geometry": "POINT(-65 -65)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CONDUCTIVITY SENSORS \u003e CONDUCTIVITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e RADIATION SENSORS", "is_usap_dc": true, "keywords": "MOORED; WATER TEMPERATURE; CONDUCTIVITY; FLUORESCENCE; UNCREWED VEHICLES; Palmer Station; PHOTOSYNTHETICALLY ACTIVE RADIATION; PELAGIC; OCEAN MIXED LAYER; SURFACE; SALINITY; WATER PRESSURE; LIVING ORGANISM; MODELS; ACOUSTIC SCATTERING", "locations": "Palmer Station", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Instrumentation and Support; Antarctic Ocean and Atmospheric Sciences; Antarctic Integrated System Science", "paleo_time": "NOT APPLICABLE", "persons": "Bernard, Kim; Oliver, Matthew; Kohut, Josh; Fraser, William; Klinck, John M.; Statcewich, Hank", "platforms": "LIVING ORGANISM-BASED PLATFORMS \u003e LIVING ORGANISM; OTHER \u003e MODELS; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED; WATER-BASED PLATFORMS \u003e UNCREWED VEHICLES; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE", "repo": "BCO-DMO", "repositories": "BCO-DMO; IOOS Glider DAAC", "science_programs": null, "south": -70.0, "title": "Collaborative Research: Physical Mechanisms Driving Food Web Focusing in Antarctic Biological Hotspots", "uid": "p0010346", "west": -75.0}, {"awards": "2139497 Balco, Gregory", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 21 Jun 2022 00:00:00 GMT", "description": "This project will conduct basic research into geological dating techniques that are useful for determining the age of glacial deposits in polar regions, Antarctica in particular. These techniques are necessary for determining how large the polar ice sheets were in the geologic past, including during past periods of warm climate that likely resemble present and near-future conditions. Thus, they represent an important technical capability needed for estimating the response of polar ice sheets to climate warming. Because changes in the size of polar ice sheets are the largest potential contribution to future global sea-level change, this capability is also relevant to understanding likely sea-level impacts of future climate change. The research in this project comprises several observational and experimental approaches to improving the speed, efficiency, cost, and accuracy of these techniques, as well as a scientific outreach program aimed at making the resulting capabilities more broadly available to other researchers. The project supports a postdoctoral scholar and contributes to human resources development in polar and climate science. The project focuses on several areas of cosmogenic-nuclide geochemistry, which is a geochemical dating method that relies on the production and decay of cosmic-ray-produced radionuclides in surface rocks. Measurements of these nuclides can be used to quantify the duration of surface exposure and ice cover at locations in Antarctica that are covered and uncovered by changes in the size of the Antarctic ice sheets, thus providing a means of reconstructing past ice-sheet change. The first proposed set of experiments are aimed at implementing a \u0027virtual mineral separation\u0027 approach to cosmogenic noble gas analysis that may allow measurement of nuclide concentrations in certain minerals without physically separating the minerals from the host rock. If feasible, this would realize significant speed and cost improvements for this type of analysis. A second set of experiments will focus on means of identifying and quantifying non-cosmogenic background inventories of some relevant nuclides, which is intended to improve the measurement sensitivity and precision for cosmic-ray-produced inventories of these nuclides. A third focus area aims to improve capabilities to measure multiple cosmic-ray-produced nuclides in the same sample, which has the potential to improve the accuracy of dating methods based on these nuclides and to expand the situations in which these methods can be applied. If successful, these experiments are likely to improve a number of applications of cosmogenic-nuclide geochemistry relevant to Antarctic research, including subglacial bedrock exposure dating, dating of multimillion-year-old glacial deposits, and surface-process studies useful in understanding landform evolution and ecosystem dynamics. 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": "California; LABORATORY; AMD; GEOCHEMISTRY; Amd/Us; USAP-DC; USA/NSF", "locations": "California", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Balco, Gregory", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -90.0, "title": "Targeted Basic Research to Enable Antarctic Science Applications of Cosmogenic-Nuclide Geochemistry", "uid": "p0010343", "west": -180.0}, {"awards": "2201129 Fischer, Karen", "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": "Crustal thicknesses in Antarctica from Sp receiver functions; Lithospheric thicknesses in Antarctica from Sp receiver functions", "datasets": [{"dataset_uid": "601899", "doi": "10.15784/601899", "keywords": "Antarctica; Cryosphere; LAB; Lithosphere; Lithospheric Thickness", "people": "Fischer, Karen; Brown, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Lithospheric thicknesses in Antarctica from Sp receiver functions", "url": "https://www.usap-dc.org/view/dataset/601899"}, {"dataset_uid": "601898", "doi": "10.15784/601898", "keywords": "Antarctica; Crust; Cryosphere; Moho", "people": "Fischer, Karen; Brown, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Crustal thicknesses in Antarctica from Sp receiver functions", "url": "https://www.usap-dc.org/view/dataset/601898"}], "date_created": "Tue, 14 Jun 2022 00:00:00 GMT", "description": "The western portion of the Antarctic continent is very active in terms of plate tectonic processes that can produce significant variations in the Earths mantle temperature as well as partial melting of the mantle. In addition to these internal processes, the ice sheet in western Antarctica is melting due to Earths warming climate and adding water to the ocean. These changes in ice mass cause adjustments in rocks within the Earth\u0027s crust, allowing the surface to rebound in some locations and fall in others, altering the geographical pattern of sea-level change. However, the solid Earth response depends strongly on the strength of the rocks at a wide range of timescales which is not well-known and varies with temperature and other rock properties. This project has three primary goals. (1) It will assess how processes such as rifting, mantle upwelling and lithospheric instability have altered the lithosphere and underlying asthenosphere of western Antarctica, contributing to a planet-wide understanding of these processes. (2) It will use new measurements of mantle and crust properties to estimate the rate at which heat from the solid Earth flows into the base of the ice, which is important for modeling the rates at which the ice melts and flows. (3) It will places bounds on mantle viscosity, which is key for modeling the interaction of the solid Earth with changing ice and water masses and their implications for sea-level rise. To accomplish these goals, new resolution of crust and mantle structure will be obtained by analyzing seismic waves from distant earthquakes that have been recorded at numerous seismic stations in Antarctica. These analyses will include new combinations of seismic wave data that provide complementary information about mantle temperature, heat flow and viscosity. This project will provide educational and career opportunities to a Brown University graduate student, undergraduates from groups underrepresented in science who will come to Brown University for a summer research program, and other undergraduates. The project will bring together faculty and students for a seminar at Brown that explores the connections between the solid Earth and ice processes in Antarctica. Project research will be incorporated in outreach to local public elementary schools and high schools. This research addresses key questions about mantle processes and properties in western Antarctica. What are the relative impacts of rifting, mantle plumes, and lithospheric delamination in the evolution of the lithosphere and asthenosphere? Where is topography isostatically compensated, and where are dynamic processes such as plate flexure or tractions from 3-D mantle flow required? What are the bounds on heat flow and mantle viscosity, which represent important inputs to models of ice sheet evolution and its feedback from the solid Earth? To address these questions, this project will measure mantle and crust properties using seismic tools that have not yet been applied in Antarctica: regional-scale measurement of mantle attenuation from surface waves; Sp body wave phases to image mantle velocity gradients such as the lithosphere-asthenosphere boundary; and surface wave amplification and ellipticity. The resulting models of seismic attenuation and velocity will be jointly interpreted to shed new light on temperature, bulk composition, volatile content, and partial melt, using a range of laboratory-derived constitutive laws, while considering data from mantle xenoliths. To test the relative roles of rifting, mantle plumes, and delamination, and to assess isostatic support for Antarctic topography, the predictions of these processes will be compared to the new models of crust and mantle properties. To improve bounds on western Antarctic heat flow, seismic attenuation and velocity will be used in empirical comparisons and in direct modeling of vertical temperature gradients. To better measure mantle viscosity at the timescales of glacial isostatic adjustment, frequency-dependent viscosity will be estimated from the inferred mantle conditions. This project will contribute to the education and career development of the following: a Brown University Ph.D. student, Brown undergraduates, and undergraduates from outside the university will be involved through the Department of Earth, Environmental and Planetary Sciences (DEEPS) Leadership Alliance NSF Research Experience for Undergraduates (REU) Site which focuses on geoscience summer research experiences for underrepresented students. The project will be the basis for a seminar at Brown that explores the connections between the solid Earth and cryosphere in Antarctica and will contribute to outreach in local public elementary and high schools. 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": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOGRAPHS", "is_usap_dc": true, "keywords": "USAP-DC; West Antarctica; USA/NSF; SEISMIC SURFACE WAVES; AMD; PLATE TECTONICS; Amd/Us; GLACIERS/ICE SHEETS; FIELD INVESTIGATION", "locations": "West Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Fischer, Karen; Dalton, Colleen", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Probing the Western Antarctic Lithosphere and Asthenosphere with New Approaches to Imaging Seismic Wave Attenuation and Velocity", "uid": "p0010339", "west": -180.0}, {"awards": "2032029 Gerken, Sarah", "bounds_geometry": "POLYGON((-70 -62,-68.5 -62,-67 -62,-65.5 -62,-64 -62,-62.5 -62,-61 -62,-59.5 -62,-58 -62,-56.5 -62,-55 -62,-55 -62.8,-55 -63.6,-55 -64.4,-55 -65.2,-55 -66,-55 -66.8,-55 -67.6,-55 -68.4,-55 -69.2,-55 -70,-56.5 -70,-58 -70,-59.5 -70,-61 -70,-62.5 -70,-64 -70,-65.5 -70,-67 -70,-68.5 -70,-70 -70,-70 -69.2,-70 -68.4,-70 -67.6,-70 -66.8,-70 -66,-70 -65.2,-70 -64.4,-70 -63.6,-70 -62.8,-70 -62))", "dataset_titles": "Expedition Data of NBP2303; Invertebrate Zoology", "datasets": [{"dataset_uid": "200386", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP2303", "url": "https://www.rvdata.us/search/cruise/NBP2303"}, {"dataset_uid": "200385", "doi": "", "keywords": null, "people": null, "repository": "Alabama Museum of Natural History, University of Alabama, Tuscaloosa", "science_program": null, "title": "Invertebrate Zoology", "url": "https://arctos.database.museum/"}], "date_created": "Mon, 13 Jun 2022 00:00:00 GMT", "description": "Ocean communities play an important role in determining the natural and human impacts of global change. The most conspicuous members of those communities are generally large vertebrates such as marine mammals and sea birds. But smaller animals often determine how the changes impact those charismatic animals. In the Antarctic, where some of the most dramatic physical changes are taking place, we do not know much about what small animals exist. This project will sample the sub-Antarctic and three different Antarctic seas with a hope of identifying, quantifying and discovering the variation in species of a group of small invertebrates. Comma shrimp, also called cumaceans, are rarely seen elsewhere but may be common and important in the communities of these locations. Antarctic sampling traditionally used gear that was not very effective at catching cumaceans so we do not know what species exist there and how common they are. This study will utilize modern sampling methods that will allow comma shrimp to be sampled. This will lead to discoveries about the diversity and abundance of comma shrimp, as well as their relationship to other invertebrate species. Major impacts of this work will be an enhancement of museum collections, the development of description of all the comma shrimp of Antarctica including new and unnamed species. Those contributions may be especially important as we strive to understand what drives the dynamics of charismatic vertebrates and fisheries that are tied to Antarctic food webs. This project will collect cumaceans from benthic samples from Argentinian waters, Bransfield Strait, and the Weddell Sea using benthic sleds. Specimens will be fixed in 95% ethanol and preserved in 95% ethanol and 5% glycerin to preserve both morphology and DNA. The specimens will form the basis for a monograph synthesizing current knowledge on the Subantarctic and Antarctic Cumacea, including diagnoses of all species, descriptions of new species, additional description for currently unknown life stages of known species, and vouchered gene sequences for all species collected. The monograph will include keys to all families, genera and species known from the region. Monographic revisions that include identification resources are typically useful for decades to a broad spectrum of other scientists. 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": -55.0, "geometry": "POINT(-62.5 -66)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; NSF/USA; ANIMALS/INVERTEBRATES; SHIPS; USAP-DC; NBP2303; Weddell Sea; Amd/Us; Antarctic Peninsula", "locations": "Antarctic Peninsula; Weddell Sea", "north": -62.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gerken, Sarah", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "R2R", "repositories": "Alabama Museum of Natural History, University of Alabama, Tuscaloosa; R2R", "science_programs": null, "south": -70.0, "title": "RAPID: Monographing the Antarctic and Subantarctic Cumacea", "uid": "p0010338", "west": -70.0}, {"awards": "2037598 Alberto, Filipe; 2037670 Heine, John", "bounds_geometry": "POLYGON((162 -76,162.8 -76,163.6 -76,164.4 -76,165.2 -76,166 -76,166.8 -76,167.6 -76,168.4 -76,169.2 -76,170 -76,170 -76.3,170 -76.6,170 -76.9,170 -77.2,170 -77.5,170 -77.8,170 -78.1,170 -78.4,170 -78.7,170 -79,169.2 -79,168.4 -79,167.6 -79,166.8 -79,166 -79,165.2 -79,164.4 -79,163.6 -79,162.8 -79,162 -79,162 -78.7,162 -78.4,162 -78.1,162 -77.8,162 -77.5,162 -77.2,162 -76.9,162 -76.6,162 -76.3,162 -76))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 23 May 2022 00:00:00 GMT", "description": "Climate change is changing the number of sea-ice free days in coastal polar environments, which is impacting Antarctic communities. This study will evaluate the change in macroalgae (seaweed) communities to increased light availability in order to predict if macroalgae will be able to spread to newly ice-free locations faster than invertebrates (e.g., sponges, bryozoans, tunicates, and polychaetes) in shallow underwater rocky habitats. Study sites will include multiple locations in McMurdo Sound, Ross Sea, Antarctica. This study will establish patterns in plant properties, genetic diversity and reproductive characteristics of two species of seaweeds, Phyllophora antarctica and Iridaea cordata in relation to depth and light. Long-term changes will be assesed by comparing to results from a survey in 1980. This will be the first study in the region to estimate the potential effects of climate, in particular reductions in annual sea ice cover and resulting increase in light intensity and duration, on shifts in macroalgal communities in McMurdo Sound. Three-dimensional photogrammetry will also be used to evaluate benthic community structure on the newly discovered offshore Dellbridge Seamount. Visualization from the video footage will be shared with web-based interactive applications to engage and educate the public in polar ecology and factors causing changes in marine community ecosystem structure in this important region. This project is evaluating macroalgae biogeography in Antarctic coastal waters near McMurdo Sound, a relatively understudied region that is experiencing large changes in fast sea ice coverage. The population ecology and genetic diversity of nearshore shallow and deeper offshore benthic macroalgal communities of Phyllophora antarctica and Iridaea cordata will be assessed for percentage cover, biomass, blade length, and reproductive characteristics at seven locations: Cape Royds, Cape Evans, Little Razorback Islands, Turtle Rock, Arrival Heights, Granite Harbor, and Dellbridge Seamount in McMurdo Sound, Antarctica. The team is also assessing differential reproductive successes at different depths and comparing results to populations surveyed in 1980. The genetic diversity of the two species is being estimated using a combination of whole genome sequencing and species-specific microsatellite genetic markers. Samples from this study will be compared to samples collected from other regions in Antarctica such as the South Shetland Islands and Antarctic Peninsula. In addition, a macroalgal assemblage and 3D models of the community structure will be generated using photogrammetry from the newly discovered Dellbridge Seamount that is located 2 km offshore in McMurdo Sound. With the addition of photogrammetry and 3D visualization to this research, web-based applications will be used to engage and educate the public in subtidal polar ecology, population genetics, and the importance of Antarctic science to their lives. 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(166 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; McMurdo Sound; USAP-DC; Amd/Us; COMMUNITY DYNAMICS; FIELD INVESTIGATION; MACROALGAE (SEAWEEDS); USA/NSF", "locations": "McMurdo Sound", "north": -76.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Heine, John; Goldberg, Nisse; Alberto, Filipe", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": -79.0, "title": "Collaborative Research: Biogeography, Population Genetics, and Ecology of two Common Species of Fleshy Red Algae in McMurdo Sound", "uid": "p0010322", "west": 162.0}, {"awards": "2019719 Brook, Edward", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "2019-2020 Allan Hills Field Report; 2022-23 Allan Hills Intermediate Ice Core Site Selection Field Report; 2023-2024 Allan Hills End-of-Season Science Report; Airborne Radar Data: 2022-23 (CXA1) flight based HDF5/matlab format data; Airborne Radar Data: 2022-23 (CXA1) transect based (science organized) unfocused data; Airborne Radar Data: 2023-24 (CXA2) flight based data HDF5/matlab format; Airborne Radar Data: 2023-24 (CXA2) transect based (science organized) unfocused data; ALHIC2201 and ALHIC2302 3D ECM and Layer Orientations; Allan Hills 2022-23 Shallow Ice Core Field Report; Allan Hills CMC3 ice core d18Oatm, d15N, dO2/N2, dAr/N2, d40/36Ar, d40/38Ar 2021 \u0026 2022; Allan Hills I-188 Field Season Report 2022-2023; Allan Hills ice water stable isotope record for dD, d18O; Basal Ice Unit Thickness Mapped by the NSF COLDEX MARFA Ice Penetrating Radar; CO2 and CH4 from Allan Hills ice cores ALHIC1901, 1902, and 1903; COLDEX VHF MARFA Open Polar Radar radargrams; Concentration and flux of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area; Heavy noble gases (Ar/Xe/Kr) from ALHIC1901, 1902, and 1903; I-165-M GPR Field Report 2019-2020; MOT data (Xe/Kr) from Allan Hills ice cores ALHIC1901, 1902, and 1903; NSF COLDEX 2022-23 Level 2 Basal Specularity Content Profiles; NSF COLDEX 2022-23 Riegl Laser Altimeter Level 2 Geolocated Surface Elevation Triplets; NSF COLDEX 2023-24 Level 2 Basal Specularity Content Profiles; NSF COLDEX 2023-24 Riegl Laser Altimeter Level 2 Geolocated Surface Elevation Triplets; NSF COLDEX Ice Penetrating Radar Derived Grids of the Southern Flank of Dome C; NSF COLDEX/Open Polar Radar Example Delay Doppler Classification of Englacial Reflectors; NSF COLDEX Raw MARFA Ice Penetrating Radar data; Oxygen and hydrogen isotope compositions and associated d-excess of ice from ALHIC1903 drilled at the Allan Hills Blue Ice Area; Rare earth elemental concentrations of leached ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area; Replicate O-17-excess by continuous flow laser spectroscopy for an ice core section at Summit, Greenland; Rising Seas: Representations of Antarctica, Climate Change, and Sea Level Rise in U.S. Newspaper Coverage; Snapshot record of CO2 and CH4 from the Allan Hills, Antarctica, ranging from 400,000 to 3 million years old; Social network analysis to understand participant engagement in transdisciplinary team science: a large U.S. science and technology center case study; Strontium and neodymium isotope compositions of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area", "datasets": [{"dataset_uid": "601863", "doi": null, "keywords": "Allan Hills; Antarctica; Cryosphere; Isotope Data", "people": "Kurbatov, Andrei V.; Mayewski, Paul A.; Brook, Edward; Introne, Douglas; Higgins, John; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Allan Hills ice water stable isotope record for dD, d18O", "url": "https://www.usap-dc.org/view/dataset/601863"}, {"dataset_uid": "601896", "doi": "10.15784/601896", "keywords": "Allan Hills; Antarctica; Ch4; CO2; Cryosphere; Glaciology; Glaciology; Ice Core Data; Ice Core Records", "people": "Higgins, John", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "CO2 and CH4 from Allan Hills ice cores ALHIC1901, 1902, and 1903", "url": "https://www.usap-dc.org/view/dataset/601896"}, {"dataset_uid": "601897", "doi": "10.15784/601897", "keywords": "Allan Hills; Antarctica; Cryosphere; Glaciology; Ice Core Data; MOT; Ocean Temperature; Paleoclimate; Xe/Kr", "people": "Higgins, John", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "MOT data (Xe/Kr) from Allan Hills ice cores ALHIC1901, 1902, and 1903", "url": "https://www.usap-dc.org/view/dataset/601897"}, {"dataset_uid": "601878", "doi": "10.15784/601878", "keywords": "Allan Hills; Antarctica; Blue Ice; Carbon Dioxide; Cryosphere; Methane", "people": "Shackleton, Sarah; Marks Peterson, Julia; Brook, Edward; Kalk, Michael; Severinghaus, Jeffrey P.; Hishamunda, Valens", "repository": "USAP-DC", "science_program": "COLDEX", "title": "Snapshot record of CO2 and CH4 from the Allan Hills, Antarctica, ranging from 400,000 to 3 million years old", "url": "https://www.usap-dc.org/view/dataset/601878"}, {"dataset_uid": "601863", "doi": null, "keywords": "Allan Hills; 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Conway, Howard", "repository": "USAP-DC", "science_program": "COLDEX", "title": "2022-23 Allan Hills Intermediate Ice Core Site Selection Field Report", "url": "https://www.usap-dc.org/view/dataset/601697"}, {"dataset_uid": "601854", "doi": "10.15784/601854", "keywords": "Allan Hills; Antarctica; Cryosphere", "people": "Shackleton, Sarah; Kirkpatrick, Liam; Carter, Austin; Fudge, T. J.; Marks Peterson, Julia", "repository": "USAP-DC", "science_program": "COLDEX", "title": "ALHIC2201 and ALHIC2302 3D ECM and Layer Orientations", "url": "https://www.usap-dc.org/view/dataset/601854"}, {"dataset_uid": "200419", "doi": "", "keywords": null, "people": null, "repository": "University Digital Conservancy", "science_program": null, "title": "Rising Seas: Representations of Antarctica, Climate Change, and Sea Level Rise in U.S. Newspaper Coverage", "url": "https://hdl.handle.net/11299/265195"}, {"dataset_uid": "200420", "doi": "10.18738/T8/J38CO5", "keywords": null, "people": null, "repository": "OPR", "science_program": null, "title": "Airborne Radar Data: 2022-23 (CXA1) flight based HDF5/matlab format data", "url": "https://data.cresis.ku.edu/data/rds/2022_Antarctica_BaslerMKB/"}, {"dataset_uid": "200421", "doi": "10.18738/T8/J38CO5", "keywords": null, "people": null, "repository": "OPR", "science_program": null, "title": "Airborne Radar Data: 2023-24 (CXA2) flight based data HDF5/matlab format", "url": "https://data.cresis.ku.edu/data/rds/2023_Antarctica_BaslerMKB/"}, {"dataset_uid": "601826", "doi": "10.15784/601826", "keywords": "Allan Hills; Antarctica; Cryosphere", "people": "Manos, John-Morgan; Epifanio, Jenna; Conway, Howard; Shaya, Margot; Horlings, Annika", "repository": "USAP-DC", "science_program": "COLDEX", "title": "Allan Hills I-188 Field Season Report 2022-2023", "url": "https://www.usap-dc.org/view/dataset/601826"}, {"dataset_uid": "601824", "doi": "10.15784/601824", "keywords": "Allan Hills; Antarctica; Coldex; Cryosphere", "people": "Epifanio, Jenna; Marks Peterson, Julia; Higgins, John; Brook, Edward J.; Shackleton, Sarah; Carter, Austin; Manos, John-Morgan; Hudak, Abigail; Banerjee, Asmita; Morton, Elizabeth; Jayred, Michael; Goverman, Ashley; Mayo, Emalia", "repository": "USAP-DC", "science_program": "COLDEX", "title": "2023-2024 Allan Hills End-of-Season Science Report", "url": "https://www.usap-dc.org/view/dataset/601824"}, {"dataset_uid": "601819", "doi": "10.15784/601819", "keywords": "Allan Hills; Antarctica; Cryosphere", "people": "Nesbitt, Ian; Carter, Austin; Higgins, John; Shackleton, Sarah; Morgan, Jacob; Epifanio, Jenna; Kuhl, Tanner; Morton, Elizabeth; Zajicek, Anna", "repository": "USAP-DC", "science_program": "COLDEX", "title": "2019-2020 Allan Hills Field Report", "url": "https://www.usap-dc.org/view/dataset/601819"}, {"dataset_uid": "200432", "doi": "10.18738/T8/XPMLCC", "keywords": null, "people": null, "repository": "Texas Data Repository", "science_program": null, "title": "Airborne Radar Data: 2022-23 (CXA1) transect based (science organized) unfocused data", "url": "https://dataverse.tdl.org/dataset.xhtml?persistentId=doi:10.18738/T8/XPMLCC"}, {"dataset_uid": "200433", "doi": "10.18738/T8/FV6VNT", "keywords": null, "people": null, "repository": "Texas Data Repository", "science_program": null, "title": "Airborne Radar Data: 2023-24 (CXA2) transect based (science organized) unfocused data", "url": "https://dataverse.tdl.org/dataset.xhtml?persistentId=doi:10.18738/T8/FV6VNT"}, {"dataset_uid": "200434", "doi": "10.18738/T8/99IEOG", "keywords": null, "people": null, "repository": "Texas Data Repository", "science_program": null, "title": "NSF COLDEX 2022-23 Riegl Laser Altimeter Level 2 Geolocated Surface Elevation Triplets", "url": "https://doi.org/10.18738/T8/99IEOG"}, {"dataset_uid": "200435", "doi": "10.18738/T8/PNBFOL", "keywords": null, "people": null, "repository": "Texas Data Repository", "science_program": null, "title": "NSF COLDEX 2023-24 Riegl Laser Altimeter Level 2 Geolocated Surface Elevation Triplets", "url": "https://doi.org/10.18738/T8/PNBFOL"}, {"dataset_uid": "601768", "doi": "10.15784/601768", "keywords": "Antarctica; Coldex; East Antarctic Plateau; Glaciology; Radar Echo Sounder", "people": "Ng, Gregory; Kempf, Scott D.; Chan, Kristian; Kerr, Megan; Greenbaum, Jamin; Blankenship, Donald D.; Young, Duncan A.; Buhl, Dillon", "repository": "USAP-DC", "science_program": "COLDEX", "title": "NSF COLDEX Raw MARFA Ice Penetrating Radar data", "url": "https://www.usap-dc.org/view/dataset/601768"}, {"dataset_uid": "200452", "doi": "https://hdl.handle.net/11299/270020", "keywords": null, "people": null, "repository": "UMN University Digital Conservancy", "science_program": null, "title": "Social network analysis to understand participant engagement in transdisciplinary team science: a large U.S. science and technology center case study", "url": "https://hdl.handle.net/11299/270020"}, {"dataset_uid": "200470", "doi": "doi:10.15784/601822", "keywords": null, "people": null, "repository": "USAP-DC", "science_program": null, "title": "Oxygen and hydrogen isotope compositions and associated d-excess of ice from ALHIC1903 drilled at the Allan Hills Blue Ice Area", "url": "https://www.usap-dc.org/view/dataset/601822"}, {"dataset_uid": "200469", "doi": "https://doi.org/10.15784/601821", "keywords": null, "people": null, "repository": "USAP-DC", "science_program": null, "title": "Rare earth elemental concentrations of leached ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area", "url": "https://www.usap-dc.org/view/dataset/601821"}, {"dataset_uid": "601620", "doi": "10.15784/601620", "keywords": "18O; Allan Hills; Allan Hills Blue Ice; Antarctica; Blue Ice; Delta 15N; Delta 18O; Dole Effect; Firn Thickness; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Chronology; Ice Core Records", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Allan Hills CMC3 ice core d18Oatm, d15N, dO2/N2, dAr/N2, d40/36Ar, d40/38Ar 2021 \u0026 2022", "url": "https://www.usap-dc.org/view/dataset/601620"}, {"dataset_uid": "601696", "doi": "10.15784/601696", "keywords": "Allan Hills; Antarctica; Ice Core", "people": "Brook, Edward J.; Shackleton, Sarah", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Allan Hills 2022-23 Shallow Ice Core Field Report", "url": "https://www.usap-dc.org/view/dataset/601696"}, {"dataset_uid": "601669", "doi": "10.15784/601669", "keywords": "Allan Hills; Antarctica; GPR; Ice Core; Report", "people": "Nesbitt, Ian; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "I-165-M GPR Field Report 2019-2020", "url": "https://www.usap-dc.org/view/dataset/601669"}, {"dataset_uid": "200468", "doi": "https://doi.org/10.15784/601820", "keywords": null, "people": null, "repository": "USAP-DC", "science_program": null, "title": "Strontium and neodymium isotope compositions of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area", "url": "https://www.usap-dc.org/view/dataset/601820"}, {"dataset_uid": "601895", "doi": "10.15784/601895", "keywords": "Allan Hills; Antarctica; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Noble Gas", "people": "Higgins, John", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Heavy noble gases (Ar/Xe/Kr) from ALHIC1901, 1902, and 1903", "url": "https://www.usap-dc.org/view/dataset/601895"}, {"dataset_uid": "200461", "doi": "10.18738/T8/6T5JS6", "keywords": null, "people": null, "repository": "Texas Data Repository", "science_program": null, "title": "NSF COLDEX 2022-23 Level 2 Basal Specularity Content Profiles", "url": "https://doi.org/10.18738/T8/6T5JS6"}, {"dataset_uid": "200467", "doi": "doi:10.15784/601825", "keywords": null, "people": null, "repository": "USAP-DC", "science_program": null, "title": "Concentration and flux of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area", "url": "https://www.usap-dc.org/view/dataset/601825"}, {"dataset_uid": "601659", "doi": "10.15784/601659", "keywords": "Antarctica; Continuous Flow; Glaciology; Greenland; Ice Core Data; Laser Spectroscopy; Oxygen Isotope; Triple Oxygen Isotopes", "people": "Davidge, Lindsey", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "Replicate O-17-excess by continuous flow laser spectroscopy for an ice core section at Summit, Greenland", "url": "https://www.usap-dc.org/view/dataset/601659"}, {"dataset_uid": "200465", "doi": "10.18738/T8/DM10IG", "keywords": null, "people": null, "repository": "Texas Data Repository", "science_program": null, "title": "COLDEX VHF MARFA Open Polar Radar radargrams", "url": "https://doi.org/10.18738/T8/DM10IG"}, {"dataset_uid": "200464", "doi": "10.18738/T8/DM10IG", "keywords": null, "people": null, "repository": "Texas Data Repository", "science_program": null, "title": "NSF COLDEX/Open Polar Radar Example Delay Doppler Classification of Englacial Reflectors", "url": "https://doi.org/10.18738/T8/DM10IG"}, {"dataset_uid": "200463", "doi": "10.18738/T8/M77ANK", "keywords": null, "people": null, "repository": "Texas Data Repository", "science_program": null, "title": "NSF COLDEX Ice Penetrating Radar Derived Grids of the Southern Flank of Dome C", "url": "https://doi.org/10.18738/T8/M77ANK"}, {"dataset_uid": "200462", "doi": "10.18738/T8/KHUT1U", "keywords": null, "people": null, "repository": "Texas Data Repository", "science_program": null, "title": "NSF COLDEX 2023-24 Level 2 Basal Specularity Content Profiles", "url": "https://doi.org/10.18738/T8/KHUT1U"}], "date_created": "Sat, 21 May 2022 00:00:00 GMT", "description": "Cores drilled through the Antarctic ice sheet provide a remarkable window on the evolution of Earth\u2019s climate and unique samples of the ancient atmosphere. The clear link between greenhouse gases and climate revealed by ice cores underpins much of the scientific understanding of climate change. Unfortunately, the existing data do not extend far enough back in time to reveal key features of climates warmer than today. COLDEX, the Center for Oldest Ice Exploration, will solve this problem by exploring Antarctica for sites to collect the oldest possible record of past climate recorded in the ice sheet. COLDEX will provide critical information for understanding how Earth\u2019s near-future climate may evolve and why climate varies over geologic time. New technologies will be developed for exploration and analysis that will have a long legacy for future research. An archive of old ice will stimulate new research for the next generations of polar scientists. COLDEX programs will galvanize that next generation of polar researchers, bring new results to other scientific disciplines and the public, and help to create a more inclusive and diverse scientific community. Knowledge of Earth\u2019s climate history is grounded in the geologic record. This knowledge is gained by measuring chemical, biological and physical properties of geologic materials that reflect elements of climate. Ice cores retrieved from polar ice sheets play a central role in this science and provide the best evidence for a strong link between atmospheric carbon dioxide and climate on geologic timescales. The goal of COLDEX is to extend the ice-core record of past climate to at least 1.5 million years by drilling and analyzing a continuous ice core in East Antarctica, and to much older times using discontinuous ice sections at the base and margin of the ice sheet. COLDEX will develop and deploy novel radar and melt-probe tools to rapidly explore the ice, use ice-sheet models to constrain where old ice is preserved, conduct ice coring, develop new analytical systems, and produce novel paleoclimate records from locations across East Antarctica. The search for Earth\u2019s oldest ice also provides a compelling narrative for disseminating information about past and future climate change and polar science to students, teachers, the media, policy makers and the public. COLDEX will engage and incorporate these groups through targeted professional development workshops, undergraduate research experiences, a comprehensive communication program, annual scientific meetings, scholarships, and broad collaboration nationally and internationally. COLDEX will provide a focal point for efforts to increase diversity in polar science by providing field, laboratory, mentoring and networking experiences for students and early career scientists from groups underrepresented in STEM, and by continuous engagement of the entire COLDEX community in developing a more inclusive scientific culture. 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": "USA/NSF; AMD; Antarctica; Amd/Us; Coldex; USAP-DC; FIELD SURVEYS; ICE DEPTH/THICKNESS", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Polar Special Initiatives; Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward J.; Neff, Peter", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "OPR; Texas Data Repository; UMN University Digital Conservancy; University Digital Conservancy; USAP-DC", "science_programs": "COLDEX", "south": -90.0, "title": "Center for Oldest Ice Exploration", "uid": "p0010321", "west": -180.0}, {"awards": "1744856 Bromirski, Peter; 1246151 Bromirski, Peter; 1744958 Wei, Yong; 1744759 Dunham, Eric", "bounds_geometry": null, "dataset_titles": "Data for: Ocean Surface Gravity Wave Excitation of Flexural Gravity and Extensional Lamb Waves in Ice Shelves; Datasets for Model Simulations of Tsunami Propagation from Circum-Pacific Subduction Zone to West Antarctic Ice Shelves (Thwaites); Datasets of bathymetric model grids for model simulations of tsunami Propagation from Circum-Pacific Subduction Zone to West Antarctic Ice Shelves; Model simulation data of tsunami propagation in the Pacific Ocean; Model simulations of tsunami propagation from Circum-Pacific Subduction Zone to West Antarctic Ice Shelves (Ross Sea); Model Tsunami Propagation Simulation From Circum-Pacific Subduction Zones to West Antarctic Ice Shelves; Simulation of flexural-gravity wave response of Antarctic ice shelves to tsunami and infragravity waves", "datasets": [{"dataset_uid": "601561", "doi": "10.15784/601561", "keywords": "Amundsen Sea; Antarctica; Glaciology", "people": "Tazhimbetov, Nurbek; Dunham, Eric; Almquist, Martin", "repository": "USAP-DC", "science_program": null, "title": "Simulation of flexural-gravity wave response of Antarctic ice shelves to tsunami and infragravity waves", "url": "https://www.usap-dc.org/view/dataset/601561"}, {"dataset_uid": "601924", "doi": "10.15784/601924", "keywords": "Antarctica; Cryosphere; Model Simulation; Pacific Ocean; Subduction Zone Earthquakes; Tsunami; Tsunami impact; West Antarctica Ice Shelf", "people": "Wei, Yong", "repository": "USAP-DC", "science_program": null, "title": "Datasets of bathymetric model grids for model simulations of tsunami Propagation from Circum-Pacific Subduction Zone to West Antarctic Ice Shelves", "url": "https://www.usap-dc.org/view/dataset/601924"}, {"dataset_uid": "200323", "doi": "10.25740/qy001dt7463", "keywords": null, "people": null, "repository": "Stanford Digital Repository", "science_program": null, "title": "Data for: Ocean Surface Gravity Wave Excitation of Flexural Gravity and Extensional Lamb Waves in Ice Shelves", "url": "https://doi.org/10.25740/qy001dt7463"}, {"dataset_uid": "601923", "doi": "10.15784/601923", "keywords": "Antarctica; Cryosphere; Model Simulation; Ross Sea Ice Shelf; Thwaites Region; Tsunami; Tsunami impact; West Antarctica Ice Shelf", "people": "Wei, Yong", "repository": "USAP-DC", "science_program": null, "title": "Datasets for Model Simulations of Tsunami Propagation from Circum-Pacific Subduction Zone to West Antarctic Ice Shelves (Thwaites)", "url": "https://www.usap-dc.org/view/dataset/601923"}, {"dataset_uid": "601922", "doi": "10.15784/601922", "keywords": "Antarctica; Cryosphere; Model Simulation; Ross Ice Shelf; Ross Sea Ice Shelf; Subduction Zone Earthquakes; Tsunami; Tsunami impact; West Antarctica Ice Shelf", "people": "Wei, Yong", "repository": "USAP-DC", "science_program": null, "title": "Model simulations of tsunami propagation from Circum-Pacific Subduction Zone to West Antarctic Ice Shelves (Ross Sea)", "url": "https://www.usap-dc.org/view/dataset/601922"}, {"dataset_uid": "200424", "doi": "N/A", "keywords": null, "people": null, "repository": "NOAA Center for Tsunami Research (NCTR)", "science_program": null, "title": "Model Tsunami Propagation Simulation From Circum-Pacific Subduction Zones to West Antarctic Ice Shelves", "url": " https://nctr.pmel.noaa.gov/antarctica/ "}, {"dataset_uid": "601921", "doi": "10.15784/601921", "keywords": "Antarctica; Cryosphere; Model Output; Model Simulation; Pacific Ocean; Subduction Zone Earthquakes; Tsunami; Tsunami impact; West Antarctic Ice Sheet", "people": "Wei, Yong", "repository": "USAP-DC", "science_program": null, "title": "Model simulation data of tsunami propagation in the Pacific Ocean", "url": "https://www.usap-dc.org/view/dataset/601921"}], "date_created": "Mon, 16 May 2022 00:00:00 GMT", "description": "Understanding and being able to more reliably forecast ice mass loss from Antarctica is a critical research priority for Antarctic Science. Massive ice shelves buttress marine terminating glaciers, slowing the rate that land ice reaches the sea and, in turn, restraining the rate of sea level rise. To date, most work has focused on the destabilizing impacts of warmer air and water temperatures, resulting in melting that thins and weakens ice shelves. However, recent findings indicate that sea ice does not protect ice shelves from wave impacts as much as previously thought, which has raised the possibility that tsunamis and other ocean waves could affect shelf stability. This project will assess the potential for increased shelf fracturing from the impact of tsunamis and from heightened wave activity due to climate-driven changes in storm patterns and reduced sea-ice extent by developing models to investigate how wave impacts damage ice shelves. The modeling effort will allow for regional comparisons between large and small ice shelves, and provide an evaluation of the impacts of changing climate and storm patterns on ice shelves, ice sheets, glaciers, and, ultimately, sea level rise. This project will train graduate students in mathematical modeling and interdisciplinary approaches to Earth and ocean sciences. This project takes a four-pronged approach to estimating the impact of vibrations on ice shelves at the grounding zone due to tsunamis, very long period, infragravity, and storm-driven waves. First, the team will use high-resolution tsunami modeling to investigate the response of ice shelves along the West Antarctic coast to waves originating in different regions of the Pacific Ocean. Second, it will compare the response to wave impacts on grounding zones of narrow and wide ice shelves. Third, it will assess the exposure risk due to storm forcing through a reanalysis of weather and wave model data; and, finally, the team will model the propagation of ocean-wave-induced vibrations in the ice from the shelf front to and across the grounding zone. In combination, this project aims to identify locations along the Antarctic coast that are subject to enhanced, bathymetrically-focused, long-period ocean-wave impacts. Linkages between wave impacts and climate arise from potential changes in sea-ice extent in front of shelves, and changes in the magnitude, frequency, and tracks of storms. Understanding the effects of ocean waves and climate on ice-shelf integrity is critical to anticipate their contribution to the amplitude and timing of sea-level rise. Wave-driven reductions in ice-shelf stability may enhance shelf fragmentation and iceberg calving, reducing ice shelf buttressing and eventually accelerating sea-level rise. 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": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "COMPUTERS; AMD; Amd/Us; SEA ICE; Amundsen Sea; USAP-DC; USA/NSF; Ross Ice Shelf; MODELS", "locations": "Amundsen Sea; Ross Ice Shelf", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Integrated System Science", "paleo_time": null, "persons": "Dunham, Eric; Bromirski, Peter; Wei, Yong", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e MODELS \u003e MODELS", "repo": "USAP-DC", "repositories": "NOAA Center for Tsunami Research (NCTR); Stanford Digital Repository; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Do Ocean Wave Impacts Pose a Hazard to the Stability of West Antarctic Ice Shelves?", "uid": "p0010320", "west": null}, {"awards": "2045880 Sokol, Eric; 2046260 Salvatore, Mark", "bounds_geometry": "POLYGON((161.88 -77.47,162.075 -77.47,162.27 -77.47,162.465 -77.47,162.66 -77.47,162.855 -77.47,163.05 -77.47,163.245 -77.47,163.44 -77.47,163.635 -77.47,163.83 -77.47,163.83 -77.501,163.83 -77.532,163.83 -77.563,163.83 -77.594,163.83 -77.625,163.83 -77.656,163.83 -77.687,163.83 -77.718,163.83 -77.749,163.83 -77.78,163.635 -77.78,163.44 -77.78,163.245 -77.78,163.05 -77.78,162.855 -77.78,162.66 -77.78,162.465 -77.78,162.27 -77.78,162.075 -77.78,161.88 -77.78,161.88 -77.749,161.88 -77.718,161.88 -77.687,161.88 -77.656,161.88 -77.625,161.88 -77.594,161.88 -77.563,161.88 -77.532,161.88 -77.501,161.88 -77.47))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 21 Apr 2022 00:00:00 GMT", "description": "Part I: Non-technical description: Water is life and nowhere is it more notable than in deserts. Within the drylands on Earth, the Antarctic deserts, represented in this study by the McMurdo Dry Valleys, exemplify life in extreme environments with scarce water, low temperatures and long periods of darkness during the polar winter. There is a scarcity of methods to determine water availability, data necessary to predict which species are successful in the drylands, unless measurements are done manually or with field instruments. This project aims to develop a new method of determining soil moisture and use the new data to identify locations suitable for life. Combining these habitats with known species distributions in the McMurdo Dry Valleys, results from this project will predict which species should be present, and also what is the expected species distribution in a changing environment. In this way the project takes advantage of a combination of methods, from recent remote sensing products, ecological models and 30 years of field collections to bring a prediction of how life might change in the McMurdo Dry Valleys in a warmer, and possibly, moister future climate. This project benefits the National Science Foundation goals of expanding fundamental knowledge of Antarctic biota and the processes that sustain life in extreme environments. The knowledge acquired in this project will be disseminated to other drylands through training of high-school curricular programming in Native American communities of the SouthWest. Part II: Technical description: Terrestrial environments in Antarctica are characterized by low liquid water supply, sub-zero temperatures and the polar night in winter months. During summer, melting of snow patches, seasonal steams from glacial melt and vicinity to lakes provide a variety of environments that maintain life, not yet studied at landscape-scale level for habitat suitability and the processes that drive them. This project proposes to integrate remote sensing, hydrological models and ecological models to establish habitat suitability for species in the McMurdo Dry Valleys based on water availability. The approach is at a landscape level in order to establish present-day and future scenarios of species distribution. There are four main objectives: remote sensing development of moisture levels in soils, combining biological and soil data, building and calibrating models of habitat suitability by combining species distribution and environmental variability and applying statistical species distribution model. The field data to develop habitat suitability and calibration of models will leverage a the 30-year dataset collected by the McMurdo Long-Term Ecological Research program. Mechanistic models developed will be essential to predict species distribution in future climate scenarios. Training of post-doctoral researchers and a graduate student will prepare for the next generation of Antarctic scientists. Results from this project will train high-school students from native American communities in the SouthWest where similar desert conditions exist. 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": 163.83, "geometry": "POINT(162.855 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "ACTIVE LAYER; Taylor Valley; USAP-DC; Amd/Us; AMD; MODELS; USA/NSF", "locations": "Taylor Valley", "north": -77.47, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Salvatore, Mark; Gooseff, Michael N.; Sokol, Eric; Barrett, John", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -77.78, "title": "Collaborative Research: Moving Beyond the Margins: Modeling Water Availability and Habitable Terrestrial Ecosystems in the Polar Desert of the McMurdo Dry Valleys", "uid": "p0010316", "west": 161.88}, {"awards": "1543361 Kurbatov, Andrei; 1543454 Dunbar, Nelia", "bounds_geometry": "POINT(0 -90)", "dataset_titles": "Cryptotephra in SPC-14 ice core; SPICEcore visable tephra", "datasets": [{"dataset_uid": "601667", "doi": "10.15784/601667", "keywords": "Antarctica; Electron Microprobe; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; South Pole; Tephra", "people": "Iverson, Nels", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SPICEcore visable tephra", "url": "https://www.usap-dc.org/view/dataset/601667"}, {"dataset_uid": "601666", "doi": "10.15784/601666", "keywords": "Antarctica; Cryptotephra; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; South Pole; SPICEcore; Tephra", "people": "Helmick, Meredith; Kurbatov, Andrei V.; Hartman, Laura; Yates, Martin", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Cryptotephra in SPC-14 ice core", "url": "https://www.usap-dc.org/view/dataset/601666"}], "date_created": "Fri, 01 Apr 2022 00:00:00 GMT", "description": "Dunbar/1543454 Antarctic ice cores offer unparalleled records of earth?s climate back to almost one million years and perhaps beyond. Layers of volcanic ash (tephra) embedded in glacial ice can be used to establish an accurate ice core chronology. In order to use a visible or ultrafine volcanic ash layer as a time-stratigraphic marker, a unique geochemical fingerprint must be established, and this forms the basis of our research. This award will investigate the volcanic record in the 1751 m ice core that was completed at the South Pole during the 2015/16 field season. The core is in an ideal location to link the existing, established, volcanic records in East and West Antarctica, and therefore to connect and integrate those records, allowing the climate records of ice cores to be directly compared, as well as to focus research on the most widespread and significant volcanic eruptions from West Antarctica. Tephra derived from well-dated, large, tropical volcanic eruptions that may have had an impact on climate will also be studied. Recent success in identifying and analyzing very fine ash particles from these types of eruptions makes it likely that we will be able to pinpoint some of these eruptions, which will allow the sulfate peaks associated with these layers to be positively identified and dated. Volcanic forcing time series developed from earlier South Pole ice cores based on preserved sulfate were crucial for testing climate models, but without tephra analysis, the origin of these layers remains uncertain. Work on the tephra layers in the South Pole ice core has a number of significant specific objectives, some with practical applications to the basic science goals of Antarctic ice coring, and others that represent independent scientific contributions in their own right. These include: (1) providing independently dated time-intervals in the core, particularly for the deepest ice, (2) quantitatively linking tephra records across Antarctica with the goal of allowing direct and robust climate comparisons between these different parts of the continent, (3) providing information for large local eruptions, that will lead to direct estimates of eruption magnitude and dispersal patterns of Antarctic volcanoes, several of which will likely erupt again. The initial stages of the work will be carried out by identifying silicate-bearing horizons in the ice core, using several methods. Once found, silicate particles will be imaged so that morphological characteristics of the particles can be used to identify volcanic origin. Particles identified as tephra will then be chemically analyzed using electron microprobe and laser ablation ICP-MS. Samples that yield a robust chemical fingerprint will be statistically correlated to known eruptions, and this will be used to address the goals described above. Broader impacts of this project fall into the areas of education of future generation of researchers, outreach and international cooperation. These activities will continue to promote forward progress in integrating the Antarctic tephra record and more broadly tying it to the global volcanic record.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": null, "is_usap_dc": true, "keywords": "VOLCANIC DEPOSITS; South Pole", "locations": "South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Dunbar, Nelia; Iverson, Nels; Kurbatov, Andrei V.", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: Tephrochronology of a South Pole Ice Core", "uid": "p0010311", "west": 0.0}, {"awards": "1946326 Doran, Peter", "bounds_geometry": "POLYGON((161 -77.4,161.3 -77.4,161.6 -77.4,161.9 -77.4,162.2 -77.4,162.5 -77.4,162.8 -77.4,163.1 -77.4,163.4 -77.4,163.7 -77.4,164 -77.4,164 -77.46,164 -77.52,164 -77.58,164 -77.64,164 -77.7,164 -77.76,164 -77.82,164 -77.88,164 -77.94,164 -78,163.7 -78,163.4 -78,163.1 -78,162.8 -78,162.5 -78,162.2 -78,161.9 -78,161.6 -78,161.3 -78,161 -78,161 -77.94,161 -77.88,161 -77.82,161 -77.76,161 -77.7,161 -77.64,161 -77.58,161 -77.52,161 -77.46,161 -77.4))", "dataset_titles": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers: Infrared Stimulated Luminescence data; EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers: in situ 14C data", "datasets": [{"dataset_uid": "601520", "doi": "10.15784/601520", "keywords": "Antarctica; Sample/collection Description; Sample/Collection Description; Sample Location; Taylor Valley", "people": "Doran, Peter; Stone, Michael", "repository": "USAP-DC", "science_program": "LTER", "title": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers: Infrared Stimulated Luminescence data", "url": "https://www.usap-dc.org/view/dataset/601520"}, {"dataset_uid": "601521", "doi": "10.15784/601521", "keywords": "Antarctica; Carbon-14; Sample/collection Description; Sample/Collection Description; Sample Location; Taylor Valley", "people": "Doran, Peter; Stone, Michael", "repository": "USAP-DC", "science_program": null, "title": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers: in situ 14C data", "url": "https://www.usap-dc.org/view/dataset/601521"}], "date_created": "Mon, 31 Jan 2022 00:00:00 GMT", "description": "Correlating ecosystem responses to past climate forcing is highly dependent on the use of reliable techniques for establishing the age of events (dating techniques). In Antarctic dry regions (land areas without glaciers), carbon-14 dating has been used to assess the ages of organic deposits left behind by ancient lakes. However, the reliability of the ages is debatable because of possible contamination with \"old carbon\" from the surrounding landscape. The proposed research will attempt to establish two alternate dating techniques, in situ carbon-14 cosmogenic radionuclide exposure dating and optically stimulated luminescence (OSL), as reliable alternate dating methods for lake history in Antarctic dry areas that are not contaminated by the old carbon. The end goal will be to increase scientific understanding of lake level fluctuation in the lakes of Taylor Valley, Antarctica so that inference about past climate, glacier, and ecosystem response can be inferred. The results of this study will provide a coarse-scale absolute chronology for lake level history in Taylor Valley, demonstrate that exposure dating and OSL are effective means to understand the physical dynamics of ancient water bodies, and increase the current understanding of polar lacustrine and ice sheet responses to past and present climatic changes. These chronologies will allow polar lake level fluctuations to be correlated with past changes in global and regional climate, providing information critical for understanding and modeling the physical responses of these environments to modern change. This research supports a PhD student; the student will highlight this work with grade school classes in the United States. This research aims to establish in situ carbon-14 exposure dating and OSL as reliable alternate (to carbon-14 of organic lake deposits) geochronometers that can be used to settle the long-disputed lacustrine history and chronology of Taylor Valley, Antarctica and elsewhere. Improved lake level history will have significant impacts for the McMurdo Dry Valleys Long Term Ecological Research (MCM LTER) site as the legacy of fluctuating lake levels of the past affects the distribution of organic matter and nutrients, and impacts biological connectivity valley-wide. This work will provide insight into the carbon reservoir of large glacial lakes in the late Holocene and have implications for previously reported radiocarbon chronologies. OSL samples will be analyzed in the Desert Research Institute Luminescence Laboratory in Reno, NV. For the in situ carbon-14 work, rock samples extracted from boulders and bedrock surfaces will be prepared at Tulane University. The prepared in situ carbon-14 samples will be analyzed at the National Ocean Sciences Accelerator Mass Spectrometry laboratory in Woods Hole, MA. The two datasets will be combined to produce a reliable, coarse scale chronology for late Quaternary lake level fluctuations in Taylor Valley. 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": 164.0, "geometry": "POINT(162.5 -77.7)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; Amd/Us; Taylor Valley; AGE DETERMINATIONS; USA/NSF; AMD; USAP-DC", "locations": "Taylor Valley", "north": -77.4, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Earth Sciences", "paleo_time": null, "persons": "Doran, Peter", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LTER", "south": -78.0, "title": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers", "uid": "p0010294", "west": 161.0}, {"awards": "2139051 Guitard, Michelle", "bounds_geometry": "POLYGON((-45 -57,-44.3 -57,-43.6 -57,-42.9 -57,-42.2 -57,-41.5 -57,-40.8 -57,-40.1 -57,-39.4 -57,-38.7 -57,-38 -57,-38 -57.5,-38 -58,-38 -58.5,-38 -59,-38 -59.5,-38 -60,-38 -60.5,-38 -61,-38 -61.5,-38 -62,-38.7 -62,-39.4 -62,-40.1 -62,-40.8 -62,-41.5 -62,-42.2 -62,-42.9 -62,-43.6 -62,-44.3 -62,-45 -62,-45 -61.5,-45 -61,-45 -60.5,-45 -60,-45 -59.5,-45 -59,-45 -58.5,-45 -58,-45 -57.5,-45 -57))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 05 Nov 2021 00:00:00 GMT", "description": "Antarctic Ice Sheet stability remains a large uncertainty in predicting future sea level. Presently, the greatest ice mass loss is observed in locations where relatively warm water comes into contact with glaciers and ice shelves, melting them from below. This has led researchers to hypothesize that the interactions that occur between the ocean and the ice are important for determining ice sheet stability and that increased warm water presence will accelerate Antarctic ice mass loss and lead to greater sea level rise in the coming century. To better predict future ice sheet behavior, it is critical to understand past ice-ocean interactions around Antarctica, especially during warm periods and at times when Earth\u2019s climate was undergoing major changes. Past Antarctic ice mass and environmental conditions like ocean temperature can be reconstructed using sediments, which capture an environmental record as they accumulate on the ocean floor. By looking at sediment composition and by analyzing geochemical signatures within the sediment, it is possible to piece together a record of climate change on hundred- to million-year timescales. This project will reconstruct upper ocean temperatures and Antarctic ice retreat/advance cycles from 2.6 to 0.7 million years ago, which encompasses the Mid-Pleistocene Transition, a time in Earth\u2019s history that marks the shift from 41-thousand year glacial cycles to 100-thousand year glacial cycles. A record will be generated from existing sediment cores collected from the Scotia Sea during International Ocean Discovery Program Expedition 382. The Mid-Pleistocene Transition (MPT; ~1.25\u20130.7 Ma) marks the shift from glacial-interglacial cycles paced by obliquity (~41 kyr cycles) to those paced by eccentricity (~100-kyr cycles). This transition occurred despite little variation in Earth\u2019s orbital parameters, suggesting a role for internal climate feedbacks. The MPT was accompanied by decreasing atmospheric pCO2, increasing deep ocean carbon storage, and changes in deep water formation and distribution, all of which are linked to Antarctic margin atmosphere-ice-ocean interactions. However, Pleistocene records that document such interactions are rarely preserved on the shelf due to repeated Antarctic Ice Sheet (AIS) advance; instead, they are preserved in deep Southern Ocean basins. This project takes advantage of the excellent preservation and recovery of continuous Pleistocene sediment sequences collected from the Scotia Sea during International Ocean Discovery Program Expedition 382 to test the following hypotheses: 1) Southern Ocean upper ocean temperatures vary on orbital timescales during the early to middle Pleistocene (2.6\u20130.7 Ma), and 2) Southern Ocean temperatures co-vary with AIS advance/retreat cycles. Paleotemperatures will be reconstructed using the TetraEther indeX of 86 carbons (TEX86), a proxy that utilizes marine archaeal biomarkers. The Scotia Sea TEX86-based paleotemperature record will be compared to records of AIS variability, including ice rafted debris. Expedition 382 records will be compared to orbitally paced climatic time series and the benthic oxygen isotope record of global ice volume and bottom water temperature to determine if a correlation exists between upper ocean temperature, AIS retreat/advance, and orbital climate forcing. 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": -38.0, "geometry": "POINT(-41.5 -59.5)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; SEA SURFACE TEMPERATURE; USAP-DC; USA/NSF; LABORATORY; AMD; Scotia Sea", "locations": "Scotia Sea", "north": -57.0, "nsf_funding_programs": "Post Doc/Travel", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Michelle, Guitard", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -62.0, "title": "Investigating the influence of ocean temperature on Antarctic Ice Sheet evolution during the early to middle Pleistocene ", "uid": "p0010275", "west": -45.0}, {"awards": "1744949 Campbell, Seth; 1744927 Mitrovica, Jerry; 1745015 Zimmerer, Matthew", "bounds_geometry": "POLYGON((-145 -74,-141.6 -74,-138.2 -74,-134.8 -74,-131.4 -74,-128 -74,-124.6 -74,-121.2 -74,-117.8 -74,-114.4 -74,-111 -74,-111 -74.6,-111 -75.2,-111 -75.8,-111 -76.4,-111 -77,-111 -77.6,-111 -78.2,-111 -78.8,-111 -79.4,-111 -80,-114.4 -80,-117.8 -80,-121.2 -80,-124.6 -80,-128 -80,-131.4 -80,-134.8 -80,-138.2 -80,-141.6 -80,-145 -80,-145 -79.4,-145 -78.8,-145 -78.2,-145 -77.6,-145 -77,-145 -76.4,-145 -75.8,-145 -75.2,-145 -74.6,-145 -74))", "dataset_titles": "Mt. Waesche ground-penetrating radar data 2018-2019", "datasets": [{"dataset_uid": "601490", "doi": "10.15784/601490", "keywords": "Antarctica; GPR; Mt. Waesche", "people": "Braddock, Scott", "repository": "USAP-DC", "science_program": null, "title": "Mt. Waesche ground-penetrating radar data 2018-2019", "url": "https://www.usap-dc.org/view/dataset/601490"}], "date_created": "Fri, 22 Oct 2021 00:00:00 GMT", "description": "This study will collect a novel dataset to determine how the West Antarctic Ice Sheet (WAIS) responded to a warmer climate during the last interglacial period (~125,000 years ago) by reconstructing the glacial history at the Mt. Waesche volcano. Reconstructing WAIS geometry when the ice sheet was smaller than present is difficult and data are lacking because the evidence lies beneath the present ice sheet. This study will drill through the ice sheet and recover bedrock that can be analyzed for its surface exposure history to help determine when the surface became overridden by the ice sheet. This study will provide constraints on the past maximum and minimum spatial extent of WAIS during the last glacial-interglacial cycle. Understanding the geometry of a reduced WAIS during intervals when the planet was warmer than present may provide a possible analogue for future environmental conditions given predicted temperature trends. A reduction of WAIS results in rising sea levels which threatens coastal communities across the globe. The data will help improve numerical ice sheet models to better predict WAIS response to current and future climate trends. The project supports a teacher educational workshop and the training of graduate and undergraduate students. The goal of this project is to obtain rock samples from beneath the WAIS through shallow (\u003c80 m) drilling at Mt. Waesche, a volcano in Marie Byrd Land, near an ice dome of WAIS (2000 m elevation). The lithologies of lava flows exposed on the flank of the volcano are well-suited for cosmogenic 3He and 36Cl as well as 40Ar/39Ar measurements which will establish eruption and exposure age. Existing 40Ar/39Ar data indicate basaltic lava flows on the volcano flank as young as 350 ka. Thus, measured cosmogenic nuclides measured in rock cores from beneath the ice surface will be indicative of relatively recent exposure during periods of reduced ice elevation, most likely, during the last interglacial. The first field season is focused on identifying appropriate locations for drilling and a ground penetrating radar (GPR) survey of the subglacial topography \u003c100m under the blue ice area. Mapping and dating the adjacent exposed lava flows will allow tracing of lava flows of known age and composition below the ice margin that will be targeted for drilling the following year. The second field season activities include drilling 8 boreholes (two transects) through blue ice with the Winkie drill near the ice margin to 80 m depth to obtain rock cores from the sub-ice lava flows. 3He exposure ages will constrain the duration and minimum extent of past surface lowering of the WAIS in Marie Byrd Land. Deeper GPR imaging (up to 700 m) will hope to reveal additional evidence of lava/ice interactions that would independently place constraints on lower ice levels during past eruptions. Results from this study will be compared with the modeled ice elevation histories at Mt. Waesche to validate ice sheet modeling efforts. 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": -111.0, "geometry": "POINT(-128 -77)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; Mt. Waesche; USA/NSF; SNOW/ICE; GLACIER THICKNESS/ICE SHEET THICKNESS; PALEOCLIMATE RECONSTRUCTIONS; LABORATORY; LAVA COMPOSITION/TEXTURE; Amd/Us; AMD; USAP-DC", "locations": "Mt. Waesche", "north": -74.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Braddock, Scott; Campbell, Seth; Ackert, Robert; Zimmerer, Matthew; Mitrovica, Jerry", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Collaborative Research: Constraining West Antarctic Ice Sheet elevation during the last interglacial", "uid": "p0010272", "west": -145.0}, {"awards": "2049332 Chu, Winnie", "bounds_geometry": "POLYGON((-180 -75,-175 -75,-170 -75,-165 -75,-160 -75,-155 -75,-150 -75,-145 -75,-140 -75,-135 -75,-130 -75,-130 -76.1,-130 -77.2,-130 -78.3,-130 -79.4,-130 -80.5,-130 -81.6,-130 -82.7,-130 -83.8,-130 -84.9,-130 -86,-135 -86,-140 -86,-145 -86,-150 -86,-155 -86,-160 -86,-165 -86,-170 -86,-175 -86,180 -86,177.5 -86,175 -86,172.5 -86,170 -86,167.5 -86,165 -86,162.5 -86,160 -86,157.5 -86,155 -86,155 -84.9,155 -83.8,155 -82.7,155 -81.6,155 -80.5,155 -79.4,155 -78.3,155 -77.2,155 -76.1,155 -75,157.5 -75,160 -75,162.5 -75,165 -75,167.5 -75,170 -75,172.5 -75,175 -75,177.5 -75,-180 -75))", "dataset_titles": "Frozen Legacies - This repository hosts scientific journals and processing codes via Python and MATLab for the historical SPRI-NSF-TUD Campaign in Antarctica.", "datasets": [{"dataset_uid": "200466", "doi": "", "keywords": null, "people": null, "repository": "Frozen Legacies ", "science_program": null, "title": "Frozen Legacies - This repository hosts scientific journals and processing codes via Python and MATLab for the historical SPRI-NSF-TUD Campaign in Antarctica.", "url": "https://github.com/tarzona/frozenlegacies"}], "date_created": "Wed, 15 Sep 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). Ice shelves play a critical role in restricting the seaward flow of grounded glacier ice by providing buttressing at their bases and sides. Processes that affect the long-term stability of ice shelves can therefore influence the future contribution of the Antarctic Ice Sheet to global sea-level rise. The Ross Ice Shelf is the largest ice shelf on Earth, and it buttresses massive areas of West and East Antarctica. Previous studies of modern ice velocity indicated that the Ross Ice Shelf\u2019s mass loss is roughly balanced by its mass gain. However, more recent work that extends further back in time reveals the ice shelf is likely not in steady state, with possible long-term thinning since the late 1990s. Consequently, to accurately interpret modern-day ice-shelf changes, long-term observations are critical to evaluate how these recent variations fit into the historical context of ice-shelf variability. This project will examine more than four decades of historical and modern airborne radar sounding observations of the Ross Ice Shelf (spanning 1971 to 2017) to investigate ice-shelf changes on decadal timescales. The team will process, calibrate, and analyze radar data collected during 1971-79 field campaigns and compare them against modern observations collected between 2011-17. They will estimate basal melt rates by examining changes in ice-shelf thickness, and will determine other important metrics for melt, including ice-shelf roughness, englacial temperature, and marine-ice formation. The project will support the education of a Ph.D. student at each of the three participating institutions. In addition, the project will support the training of undergraduate and high-school researchers in radioglaciology and Antarctic sciences. The project will test the hypothesis that, over decadal timescales, the basal melt rates beneath the Ross Ice Shelf have been low, particularly under shallow ice drafts, leading to overall thickening and increased buttressing potential. The team aims to provide a direct estimate of basal melt rates based on changes in ice-shelf thickness that occurred between 1971 and 2017. This project will extend similar work completed at Thwaites Glacier and improve the calibration methods on the vertical scaling for fast-time and depth conversion. The work will also leverage the dense modern surveys to improve the geolocation of radar film collected on earlier field campaigns to produce a more precise comparison of local shelf thickness with the modern data. In addition, the team will conduct englacial attenuation analysis to calculate englacial temperature to infer the trends in local basal melting. They will also examine the radiometric and scatterometric character of bed echoes at the ice-ocean boundary to characterize changes in ice-shelf basal roughness, marine-ice formation related to local basal freezing, and structural damage from fracture processes. 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": -130.0, "geometry": "POINT(-167.5 -80.5)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; Antarctic Ice Sheet; GLACIER THICKNESS/ICE SHEET THICKNESS; USAP-DC; AMD; Transantarctic Mountains; Amd/Us; Siple Coast; GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHY; FIELD SURVEYS; USA/NSF; Ross Ice Shelf", "locations": "Ross Ice Shelf; Antarctic Ice Sheet; Siple Coast; Transantarctic Mountains", "north": -75.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Chu, Winnie; Schroeder, Dustin; Siegfried, Matthew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "Frozen Legacies ", "repositories": "Frozen Legacies ", "science_programs": null, "south": -86.0, "title": "Collaborative Research: Investigating Four Decades of Ross Ice Shelf Subsurface Change with Historical and Modern Radar Sounding Data", "uid": "p0010265", "west": 155.0}, {"awards": "1656126 Koppers, Anthony", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "OSU Marine and Geology Repository", "datasets": [{"dataset_uid": "200245", "doi": null, "keywords": null, "people": null, "repository": "OSU-MGR", "science_program": null, "title": "OSU Marine and Geology Repository", "url": "https://osu-mgr.org/"}], "date_created": "Fri, 10 Sep 2021 00:00:00 GMT", "description": "Nontechnical Description The Antarctic core collection, curated at Florida State University since 1963, is one of the world?s premier marine geology collections. Consisting of irreplaceable sediment cores, this archive has greatly advanced the understanding of the Earth system, past and present, and will remain critical to future studies of the Earth. Given Oregon State University?s (OSU) leadership in marine research and long track record providing state-of-the-art curatorial services through the OSU Marine and Geology Repository, this facility will provide world-class curatorial stewardship of the Antarctic core collection for decades to come. The Antarctic core collection will be co-located and co-managed with the current OSU collection in a single modern repository and analytical facility. The combined collection will contain more than 30 km of refrigerated sediment core from the world?s oceans and will be housed in a new 33,000 SFT facility purchased in 2009 by OSU and upgraded in 2016-17. The total refrigerated space can hold both collections comfortably and has at least five decades of expansion space. The co-location and co-management of these two collections, paired with a modern suite of analytical facilities, will lead to greater collaboration, cross-pollination of ideas, and availability of enhanced technical services and capabilities for a growing user group that increasingly relies on marine sediments. The facility will employ a comprehensive community interaction plan that takes advantage of the new OSU Marine and Geology Repository building with a 32-person seminar room, its large 1,044 square foot core lab, and ten adjoining analytical laboratories, which will provide scientific and experiential learning opportunities for students, the general public, and the Earth Sciences research community. The facility will organize small group meetings, sampling parties and summer schools that will complement ongoing support for teaching, training and learning through the use of the repository in graduate, undergraduate, and K-12 classes and Research Experience for Undergraduate programs. The repository is open to the general public for tours and presentations, and the data products derived from the facility will be disseminated via the repository website at http://osu-mgr.org/ and other national databases. Technical Description The Antarctic and the Southern Ocean National Collection of Rock and Sediment Cores currently housed at Florida State University will be relocated to Oregon State University (OSU) and housed along with the OSU Marine and Geology Repository. Oregon State University investigators will co-manage the Antarctic core collection and the Marine and Geology Repository as a single modern repository and analytical facility. The combined collection will be housed a new 33,000 square foot building with refrigerated space that can hold both collections with approximately five decades of expansion space. The co-location and co-management of these two collections offers unique curatorial synergies, cost savings, and improved capabilities to support both the research and educational needs of a wider marine and Antarctic communities. The facility will house a 32-person seminar room, a large 1,044 square foot core lab that allows layout, inspection and examination of cores, and adjoining analytical laboratories that will provide quantitative analysis as well as experiential learning opportunities for students.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": true, "keywords": "Dredge Samples; MARINE SEDIMENTS; Amd/Us; AMD; SHIPS; USAP-DC; Antarctica; USA/NSF; Sediment Core", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Instrumentation and Support", "paleo_time": null, "persons": "Koppers, Anthony; Stoner, Joseph", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "OSU-MGR", "repositories": "OSU-MGR", "science_programs": null, "south": -90.0, "title": "Curatorial Stewardship of the Antarctic and the Southern Ocean National Collection of Rock and Sediment Cores at the OSU Marine and Geology Repository", "uid": "p0010262", "west": -180.0}, {"awards": "2436582 Grunow, Anne; 1643713 Grunow, Anne; 1141906 Grunow, Anne; 0739480 Grunow, Anne; 2137467 Grunow, Anne; 0440695 Grunow, Anne; 9910267 Grunow, Anne", "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": "Marine Geoscience Data System - cruise links; Polar Rock Repository; SESAR sample registration", "datasets": [{"dataset_uid": "200243", "doi": "", "keywords": null, "people": null, "repository": "PRR", "science_program": null, "title": "Polar Rock Repository", "url": "https://prr.osu.edu/"}, {"dataset_uid": "200359", "doi": "", "keywords": null, "people": null, "repository": "PRR", "science_program": null, "title": "Polar Rock Repository", "url": "http://research.bpcrc.osu.edu/rr/"}, {"dataset_uid": "200241", "doi": "", "keywords": null, "people": null, "repository": "SESAR", "science_program": null, "title": "SESAR sample registration", "url": "https://www.geosamples.org/about/services#igsnregistration"}, {"dataset_uid": "200242", "doi": "", "keywords": null, "people": null, "repository": "MGDS", "science_program": null, "title": "Marine Geoscience Data System - cruise links", "url": "https://www.marine-geo.org/"}], "date_created": "Thu, 09 Sep 2021 00:00:00 GMT", "description": "Non-Technical Abstract: The Polar Rock Repository (PRR) at The Ohio State University provides a unique resource for researchers studying the polar regions by offering free access to geological samples and data. This project seeks support to continue expanding and managing the collection, which is vital for scientific studies and planning fieldwork in Antarctica. Over the next five years, the repository plans to add tens of thousands of new samples and images, making it easier for researchers to study polar geology without the high cost and environmental impact of traveling to remote Antarctic locations. The PRR also supports education and outreach by providing hands-on resources for schools, colleges, and the public, including a \"Polar Rock Box\" program that brings real Antarctic samples into classrooms. This work ensures the preservation of important scientific materials and makes them accessible to a broad community, advancing understanding of our planet\u2019s polar regions. Technical Abstract: The Polar Rock Repository (PRR) at The Ohio State University serves as a critical resource for polar earth science research, offering no-cost loans of geological samples and comprehensive metadata to the scientific community. This proposal seeks funding to support the continued curation, expansion, and management of the PRR, alongside its educational and outreach initiatives. Over the next five years, the PRR anticipates acquiring approximately 15,000 new samples, including those from major drilling operations (RAID, Winkie drill cores) and polar cruises. The repository also aims to significantly grow its archives of images, petrographic thin sections, and mineral separates. By preserving these physical and digital assets in a discoverable online database, the PRR fosters transparency, reproducibility, and accessibility in polar research, fulfilling Antarctic data management mandates. The intellectual merit lies in enabling cutting-edge scientific analyses through freely available samples and metadata. Broader impacts include reduced environmental costs of Antarctic research, enhanced educational opportunities, and outreach to a diverse audience through initiatives like the \"Polar Rock Box\" program. 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": "USAP-DC; FIELD SURVEYS; Pacific Ocean; ROCKS/MINERALS/CRYSTALS; GLACIATION; AMD; Weddell Sea; Scotia Sea; TECTONICS; Antarctica; Southern Ocean; Amd/Us; USA/NSF; Amundsen Sea", "locations": "Pacific Ocean; Amundsen Sea; Scotia Sea; Weddell Sea; Antarctica; Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Grunow, Anne", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "PRR", "repositories": "MGDS; PRR; SESAR", "science_programs": null, "south": -90.0, "title": "Continuing Operations Proposal: \r\nThe Polar Rock Repository as a Resource for Earth Systems Science\r\n", "uid": "p0010259", "west": -180.0}, {"awards": "2039432 Grapenthin, Ronni", "bounds_geometry": "POLYGON((165.5 -77.1,165.91 -77.1,166.32 -77.1,166.73 -77.1,167.14 -77.1,167.55 -77.1,167.96 -77.1,168.37 -77.1,168.78 -77.1,169.19 -77.1,169.6 -77.1,169.6 -77.18,169.6 -77.26,169.6 -77.34,169.6 -77.42,169.6 -77.5,169.6 -77.58,169.6 -77.66,169.6 -77.74,169.6 -77.82,169.6 -77.9,169.19 -77.9,168.78 -77.9,168.37 -77.9,167.96 -77.9,167.55 -77.9,167.14 -77.9,166.73 -77.9,166.32 -77.9,165.91 -77.9,165.5 -77.9,165.5 -77.82,165.5 -77.74,165.5 -77.66,165.5 -77.58,165.5 -77.5,165.5 -77.42,165.5 -77.34,165.5 -77.26,165.5 -77.18,165.5 -77.1))", "dataset_titles": "Erebus GPS timeseries ", "datasets": [{"dataset_uid": "601471", "doi": "10.15784/601471", "keywords": "Antarctica; GPS; Mount Erebus; Ross Island", "people": "Grapenthin, Ronni", "repository": "USAP-DC", "science_program": null, "title": "Erebus GPS timeseries ", "url": "https://www.usap-dc.org/view/dataset/601471"}], "date_created": "Fri, 03 Sep 2021 00:00:00 GMT", "description": "Nontechnical Abstract Mount Erebus volcano on Ross Island, Antarctica, is the southernmost active volcano on the planet. It provides a natural laboratory to study a volcanic system that has been in a continuous state of activity with a persistent lava lake over at least the last 40 years. Worldwide only four other volcanoes with such long-lived lava lakes exist: Erta Ale, Ethiopia; Kilauea, Hawaii; Nyiragongo, Congo; and Ambrym, Vanuatu. These volcanoes are a rare anomaly that provide a window into the underlying magmatic system and behavior. Erebus is of particular interest as it cycles through phases of very explosive activity every 20 thousand years. This project will investigate interactions between the magmatic system, the rift it is located in, and the impact of the gravitational load the volcano imposes on the underlying crust and its own magmatic system. Possible interactions between these factors may explain the changes in activity. The project will analyze geophysical data that have been collected at Erebus over at least the last two decades. The results of this work will be available to the public and scientific community and inform geodynamic models in this region. The project funds an early-career scientist and a graduate student at New Mexico Tech and contributes to the development of the next generation of scientists. Technical Abstract The proposed work targets scientific questions recently formulated by the community during the 2016 NSF-sponsored Scientific Drivers and Future of Mount Erebus Volcano Observatory workshop. The location and geometry of the magmatic plumbing from vent to lower crust system remain poorly constrained, particularly below 1 km depth. The style and causes for changes in volcanic and magmatic activity over the short term (minutes to hours) and on the decadal scale remains enigmatic. Two decades of campaign and continuous GPS data on Ross Island will inform about the longer term dynamics of both, Ross Island growing within the Terror Rift, and Erebus? deeper magmatic system. This project will organize and analyze all existing GPS data for Ross Island, and interpret any anomalies in the resulting time series. These activities require organization, consistent processing and interpretation/modeling of the existing ~20 years of GPS data, which include campaign, continuous, and high-rate GPS observations. We will generate these position time series in a consistent local reference frame and make the results, including models of transient deformation available to the community. Volcanic, tectonic and isostatic adjustment related deformation will be modeled to place Erebus in a broad volcano-tectonic framework of West Antarctica. During the data analysis phase, the utility of existing GPS data for reflection studies of snow and sea-level dynamics will also be evaluated.", "east": 169.6, "geometry": "POINT(167.55 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Ross Island; TECTONICS; USAP-DC; Amd/Us; AMD; CRUSTAL MOTION; USA/NSF; FIELD SURVEYS", "locations": "Ross Island", "north": -77.1, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Instrumentation and Facilities", "paleo_time": null, "persons": "Grapenthin, Ronni", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.9, "title": "Collaborative Research: Multi-Parameter Geophysical Constraints on Volcano Dynamics of Mt. Erebus and Ross Island, Antarctica", "uid": "p0010255", "west": 165.5}, {"awards": "2046800 Thurber, Andrew", "bounds_geometry": "POLYGON((162 -77,162.6 -77,163.2 -77,163.8 -77,164.4 -77,165 -77,165.6 -77,166.2 -77,166.8 -77,167.4 -77,168 -77,168 -77.1,168 -77.2,168 -77.3,168 -77.4,168 -77.5,168 -77.6,168 -77.7,168 -77.8,168 -77.9,168 -78,167.4 -78,166.8 -78,166.2 -78,165.6 -78,165 -78,164.4 -78,163.8 -78,163.2 -78,162.6 -78,162 -78,162 -77.9,162 -77.8,162 -77.7,162 -77.6,162 -77.5,162 -77.4,162 -77.3,162 -77.2,162 -77.1,162 -77))", "dataset_titles": null, "datasets": null, "date_created": "Sat, 21 Aug 2021 00:00:00 GMT", "description": "Part I: Non-technical description: Methane is one of the more effective atmospheric gases at retaining heat in the lower atmosphere and the earth\u2019s crust contains large quantities of methane. Research that identifies the factors that control methane\u2019s release into the atmosphere is critical to understanding and mitigating climate change. One of the most effective natural processes that inhibits the release of methane from aquatic habitats is a community of bacteria and Archaea (microbes) that use the chemical energy stored in methane, transforming methane into less-climate-sensitive compounds. The amount of methane that may be released in Antarctica is unknown, and it is unclear which microbes consume the methane before it is released from the ocean in Antarctica. This project will study one of the few methane seeps known in Antarctica to advance our understanding of which microbes inhibit the release of methane in marine environments. The research will also identify if methane is a source of energy for other Antarctic organisms. The researchers will analyze the microbial species associated with methane consumption over several years of field and laboratory research based at an Antarctic US station, McMurdo. This project clearly expands the fundamental knowledge of Antarctic systems, biota, and processes outlined as a goal in the Antarctic solicitation. This research communicates and produces educational material for K-12, college, and graduate students to inspire and inform the public about the role Antarctic ecosystems play in the global environment. This project also provides a young professor an opportunity to establish himself as an expert in the field of Antarctic microbial ecology to help solidify his academic career. Part II: Technical description: Microbes act as filter to methane release from the ocean into the atmosphere, where microbial chemosynthetic production harvests the chemical energy stored in this greenhouse gas. In spite of methane reservoirs in Antarctica being as large as Arctic permafrost, we know only a little about the taxa or dominant processes involved in methane consumption in Antarctica. The principal investigator will undertake a genomic and transcriptomic study of microbial communities developed and still developing after initiation of methane seepage in McMurdo Sound. An Antarctic methane seep was discovered at this location in 2012 after it began seeping in 2011. Five years after it began releasing methane, the methane-oxidizing microbial community was underdeveloped and methane was still escaping from the seafloor. This project will be essential in elucidating the response of microbial communities to methane release and identify how methane oxidation occurs within the constraints of the low polar temperatures. This investigation is based on 4 years of field sampling and will establish a time series of the development of cold seep microbial communities in Antarctica. A genome-to-ecosystem approach will establish how the Southern Ocean microbial community is adapted to prevent methane release into the ocean. As methane is an organic carbon source, results from this study will have implications for the Southern Ocean carbon cycle. Two graduate students will be trained and supported with undergraduates participating in laboratory activities. The researcher aims to educate, inspire and communicate about Antarctic methane seeps to a broad community. A mixed-media approach, with videos, art and education in schools will be supported in collaboration with a filmmaker, teachers and a visual artist. Students will be trained in filmmaking and K-12 students from under-represented communities will be introduced to Antarctic science through visual arts. 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": 168.0, "geometry": "POINT(165 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; USA/NSF; USAP-DC; BACTERIA/ARCHAEA; McMurdo Sound; BENTHIC; FIELD SURVEYS; Amd/Us; ECOSYSTEM FUNCTIONS", "locations": "McMurdo Sound", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Thurber, Andrew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -78.0, "title": "CAREER: Ecosystem Impacts of Microbial Succession and Production at Antarctic Methane Seeps", "uid": "p0010250", "west": 162.0}, {"awards": null, "bounds_geometry": null, "dataset_titles": "Antarctic Ice Thickness, Slipperiness, and Subglacial Lake Locations", "datasets": [{"dataset_uid": "601470", "doi": "10.15784/601470", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Ice Thickness, Slipperiness, and Subglacial Lake Locations", "url": "http://www.usap-dc.org/view/dataset/601470"}], "date_created": "Fri, 13 Aug 2021 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Antarctic Ice Sheet; Ice Thickness; Subglacial Lake", "locations": "Antarctica; Antarctic Ice Sheet", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Stubblefield, Aaron; Siegfried, Matthew; Arthern, Robert; Kingslake, Jonathan", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "2031442 Learman, Deric", "bounds_geometry": "POLYGON((-180 -60,-167.5 -60,-155 -60,-142.5 -60,-130 -60,-117.5 -60,-105 -60,-92.5 -60,-80 -60,-67.5 -60,-55 -60,-55 -62,-55 -64,-55 -66,-55 -68,-55 -70,-55 -72,-55 -74,-55 -76,-55 -78,-55 -80,-67.5 -80,-80 -80,-92.5 -80,-105 -80,-117.5 -80,-130 -80,-142.5 -80,-155 -80,-167.5 -80,180 -80,178 -80,176 -80,174 -80,172 -80,170 -80,168 -80,166 -80,164 -80,162 -80,160 -80,160 -78,160 -76,160 -74,160 -72,160 -70,160 -68,160 -66,160 -64,160 -62,160 -60,162 -60,164 -60,166 -60,168 -60,170 -60,172 -60,174 -60,176 -60,178 -60,-180 -60))", "dataset_titles": "Physical and geochemical data from shelf sediments near the Antartic Pennisula", "datasets": [{"dataset_uid": "601607", "doi": "10.15784/601607", "keywords": "Antarctica; Antarctic Peninsula; Grain Size; Grain Size Analysis; Marine Geoscience; Marine Sediments; Organic Matter Geochemistry; Sediment Core Data; Shelf Sediments; Weddell Sea", "people": "Learman, Deric", "repository": "USAP-DC", "science_program": null, "title": "Physical and geochemical data from shelf sediments near the Antartic Pennisula", "url": "https://www.usap-dc.org/view/dataset/601607"}], "date_created": "Wed, 28 Jul 2021 00:00:00 GMT", "description": "Western Antarctica is one of the fastest warming locations on Earth. Its changing climate will lead to an increase in sea-level and will also alter regional water temperature and chemistry. These changes will directly alter the microbes that inhabit the ecosystem. Microbes are the smallest forms of life on Earth, but they are also the most abundant. They drive cycling of essential nutrients, such as carbon and nitrogen that are found in ocean sediments. In this way they form the foundation of the food chain that supports larger and more complex life. However, we do not know much about how different communities of microbes break down sediments in Antarctica and this will influence the chemistry of those waters. This research will determine how communities of microbes on the coastal shelf of Antarctica degrade complex organic sediments using genetic and chemical data. This data will identify the species in the community, what enzymes they are producing and what chemical reactions they are driving. This research will create broader impacts as the data will be used to create in-class activities that improve a student\u2019s data analysis and critical thinking skills. The data will be used in graduate, undergraduate and K-12 classrooms. This research will provide genetic and enzymatic insight into how microbial communities in benthic sediments on the coastal shelf of Antarctica degrade complex organic matter. The current understanding of how benthic microbial communities respond to and then degrade complex organic matter in Antarctica is fragmented. Recent work suggests benthic microbial communities are shaped by organic matter availability. However, those studies were observational and did not directly examine community function. A preliminary study of metagenomic data from western Antarctic marine sediments, indicates a genetic potential for organic matter degradation but functional data was not been collected. Other studies have examined either enzyme activity or metagenomic potential, but few have been able to directly connect the two. To address this gap in knowledge, this study will utilize metagenomics and metatranscriptomics, coupled with microcosm experiments, enzyme assays, and geochemical data. It will examine Antarctic microbial communities from the Ross Sea, the Bransfield Strait and Weddell Sea to document how the relationship between a communities\u2019 enzymatic activity and the genes used to degrade complex organic matter is related to sediment breakdown. The data will expand our current knowledge of microbial genetic potential and provide a solid understanding of enzyme function as it relates to degradation of complex organic matter in those marine sediments. It will thereby improve our understanding of temperature change on the chemistry of Antarctic seawater. 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(-127.5 -70)", "instruments": null, "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; USAP-DC; Antarctic Peninsula; BENTHIC; SHIPS; SEDIMENT CHEMISTRY; Amd/Us; AMD; USA/NSF; Weddell Sea", "locations": "Antarctic Peninsula; Weddell Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Learman, Deric", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments", "uid": "p0010235", "west": -55.0}, {"awards": "1744989 LaRue, Michelle; 1744794 Jenouvrier, Stephanie", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Detecting climate signals in populations: case of emperor penguin; Emperor penguin population trends (2009-2018); Landfast ice: a major driver of reproductive success in a polar seabird", "datasets": [{"dataset_uid": "601513", "doi": "10.15784/601513", "keywords": "Antarctica; Breeding Success; Emperor Penguin; Fast Sea Ice", "people": "Labrousse, Sara; Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Landfast ice: a major driver of reproductive success in a polar seabird", "url": "https://www.usap-dc.org/view/dataset/601513"}, {"dataset_uid": "200388", "doi": "", "keywords": null, "people": null, "repository": "Github", "science_program": null, "title": "Emperor penguin population trends (2009-2018)", "url": "https://github.com/davidiles/EMPE_Global"}, {"dataset_uid": "601491", "doi": "10.15784/601491", "keywords": "Antarctica", "people": "Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Detecting climate signals in populations: case of emperor penguin", "url": "https://www.usap-dc.org/view/dataset/601491"}], "date_created": "Wed, 14 Jul 2021 00:00:00 GMT", "description": "The emperor penguin is an iconic seabird that is found in colonies distributed around the entirety of the Antarctic coastline. Emperor penguins are an important indicator species for the health of the Southern Ocean because their reliance on sea ice for major parts of their life cycle means that their population can be influenced by changes in the extent and duration of sea ice around Antarctica. Although baseline data exists on emperor penguin distributions and overall population size, data on how population size varies at individual colonies is limited to only a few locations. Thus, knowledge about how changes in local or regional environmental conditions impacts local or global population status is poorly understood. By combining established methods in satellite remote sensing with ground and aerial surveys of several colonies across the continent, this project will generate population estimates for the 54 known emperor penguin colonies. Decadal scale population trend data will be combined with environmental variables (e.g., sea ice extent and duration among others) to reveal which conditions influence population fluctuations at regional and continental scales. The project will engage with international collaborators, train post-doctoral associates and future scientists, and develop citizen science and K-12 outreach programs. This project on emperor penguin populations will quantify penguin presence/absence, and colony size and trajectory, across the entire Antarctic continent using high-resolution satellite imagery. For a subset of the colonies, population estimates derived from high-resolution satellite images will be compared with those determined by aerial surveys. This validated information will be used to determine population estimates for all emperor penguin colonies through iterations of supervised classification and maximum likelihood calculations on the high-resolution imagery. The effect of spatial, geophysical, and environmental variables on population size and decadal-scale trends will be assessed using generalized linear models. This research will result in a first ever empirical result for emperor penguin population trends and habitat suitability, and will leverage currently-funded NSF infrastructure and hosting sites to publish results in near-real time to the public. 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": "USA/NSF; Ross Sea; USAP-DC; AMD; COMMUNITY DYNAMICS; Amd/Us", "locations": "Ross Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "LaRue, Michelle; Ito, Emi; Jenouvrier, Stephanie", "platforms": null, "repo": "USAP-DC", "repositories": "Github; USAP-DC", "science_programs": null, "south": -90.0, "title": "A Multi-scale Approach to Understanding Spatial and Population Variability in Emperor Penguins", "uid": "p0010229", "west": -180.0}, {"awards": "1745097 Cassano, John; 1744878 Lazzara, Matthew", "bounds_geometry": "POLYGON((-115 -79,-114.4 -79,-113.8 -79,-113.2 -79,-112.6 -79,-112 -79,-111.4 -79,-110.8 -79,-110.2 -79,-109.6 -79,-109 -79,-109 -79.1,-109 -79.2,-109 -79.3,-109 -79.4,-109 -79.5,-109 -79.6,-109 -79.7,-109 -79.8,-109 -79.9,-109 -80,-109.6 -80,-110.2 -80,-110.8 -80,-111.4 -80,-112 -80,-112.6 -80,-113.2 -80,-113.8 -80,-114.4 -80,-115 -80,-115 -79.9,-115 -79.8,-115 -79.7,-115 -79.6,-115 -79.5,-115 -79.4,-115 -79.3,-115 -79.2,-115 -79.1,-115 -79))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 06 Jul 2021 00:00:00 GMT", "description": "The near surface atmosphere over West Antarctica is one of the fastest warming locations on the planet. This atmospheric warming, along with oceanic forcing, is contributing to ice sheet melt and hence rising global sea levels. An observational campaign, focused on the atmospheric boundary layer over the West Antarctic ice sheet, is envisioned. A robust set of year-round, autonomous, atmospheric and surface measurements, will be made using an instrumented 30-m tall tower at the West Antarctic ice sheet divide field camp. An additional unmanned aerial system field campaign will be conducted during the second year of this project and will supplement the West Antarctic ice sheet tall tower observations by sampling the depths of the boundary layer. The broader subject of the Antarctic ABL clearly supports a range of research activities ranging from the physics of turbulent mixing, its parameterization and constraints on meteorological forecasts, and even climatological effects, such as surface mass and energy balances. With the coming of the Thwaites WAIS program, a suite of metrological observables would be a welcome addition to the joint NSF/NERC (UK) Thwaites field campaigns. The meteorologists of this proposal have pioneered 30-m tall tower (TT) and unmanned aerial system (UAS) development in the Antarctic, and are well positioned to successfully carry out and analyze this work. In turn, the potential for these observations to advance our understanding of how the atmosphere exchanges heat with the ice sheet is high. 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": -109.0, "geometry": "POINT(-112 -79.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; Amd/Us; HUMIDITY; ATMOSPHERIC TEMPERATURE; West Antarctic Ice Sheet; BOUNDARY LAYER TEMPERATURE; USAP-DC; ATMOSPHERIC PRESSURE MEASUREMENTS; FIELD SURVEYS; BOUNDARY LAYER WINDS; USA/NSF", "locations": "West Antarctic Ice Sheet", "north": -79.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Cassano, John; Lazzara, Matthew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -80.0, "title": "Collaborative Research: Observing the Atmospheric Boundary over the West Antarctic Ice Sheet", "uid": "p0010225", "west": -115.0}, {"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": "601916", "doi": "10.15784/601916", "keywords": "Alveolata; Antarctica; Cryosphere; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Ross Sea; Xcellidae", "people": "Desvignes, Thomas; Devine, Jennifer; Postlethwait, John; P\u00e9ron, Clara", "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": "601915", "doi": "10.15784/601915", "keywords": "Alveolata; Antarctic; Cryosphere; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Xcellidae", "people": "Desvignes, Thomas; P\u00e9ron, Clara; Devine, Jennifer; Postlethwait, John", "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": "601917", "doi": "10.15784/601917", "keywords": "Alveolata; Antarctic; Cryosphere; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Xcellidae", "people": "Postlethwait, John; P\u00e9ron, Clara; Devine, Jennifer; Desvignes, Thomas", "repository": "USAP-DC", "science_program": null, "title": "Similarity matrices of Notoxcellia spp.", "url": "https://www.usap-dc.org/view/dataset/601917"}, {"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": "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": "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": "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": "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": "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": "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": "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": "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"}, {"dataset_uid": "601539", "doi": "10.15784/601539", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Notoxcellia Coronata; Notoxcellia Picta; Perkinsozoa; Xcellidae", "people": "Desvignes, Thomas; Postlethwait, John", "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": "Postlethwait, John; Lauridsen, Henrik; Desvignes, Thomas", "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": "Fontenele, Rafaela S. ; Postlethwait, John; Kraberger, Simona ; Varsani, Arvind; Desvignes, Thomas", "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; Kent, Michael L. ; Murray, Katrina N. ", "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": "601494", "doi": "10.15784/601494", "keywords": "Andvord Bay; Antarctica; Fish", "people": "Desvignes, Thomas; Postlethwait, John; Lauridsen, Henrik; Le Francois, Nathalie", "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": "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": "601892", "doi": "10.15784/601892", "keywords": "Antarctica; Biota; CO1; COX1; Cryonotothenioid; Cryosphere; Genetic Sequences; LMG1805; MT-CO1; Nototheniidae; Notothenioid; Population Genetics", "people": "Postlethwait, John; Desvignes, Thomas; Schiavon, Luca ; 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": "Valdivieso, Alejandro; Sguotti, Camilla; Cal\u00ec, Federico; Riginella, Emilio; Streeter, Margaret; Grondin, Jacob; Le Francois, Nathalie; Lucassen, Magnus; Mark, Felix C; Detrich, H. William; Papetti, Chiara; Postlethwait, John; La Mesa, Mario; Desvignes, Thomas", "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": "601496", "doi": "10.15784/601496", "keywords": "Andvord Bay; Antarctica; Fish", "people": "Desvignes, Thomas; Lauridsen, Henrik; Postlethwait, John", "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": "601501", "doi": "10.15784/601501", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Biota; Notoxcellia Coronata; Notoxcellia Picta; Oceans; Perkinsozoa; Xcellidae", "people": "Varsani, Arvind; Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "Phylogenetic Analysis of Notoxcellia species.", "url": "https://www.usap-dc.org/view/dataset/601501"}], "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": "1947094 Sidor, Christian", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 30 Jun 2021 00:00:00 GMT", "description": "Non-technical Abstract Around 252 million years ago, a major mass extinction wiped out over 90% of species on Earth. Coincident with this extinction, the Antarctic portion of the supercontinent of Pangea transitioned to a warmer climatic regime devoid of a permanent ice cap. Compared to lower latitudes, relatively little is known about the survivors of the extinction in Antarctica, although it has been hypothesized that the continents more polar location shielded it from the worst of the extinctions effects. As the result of a NSF-sponsored deep field camp in 2017/2018, a remarkable collection of vertebrate fossils was discovered in the rocks of the Shackleton Glacier region. This collection includes the best preserved and most complete materials of fossil amphibians ever recovered from Antarctica, including two previously undescribed species. This grant supports one postdoctoral researcher with expertise in fossil amphibians to describe and interpret the significance of these fossils, including their identification, relationships, and how they fit into the terrestrial ecosystem of Antarctica and other southern hemisphere terrestrial assemblages in light of the major reorganization of post-extinction environments. Historical collections of fossil amphibians will also be reviewed as part of this work. Undergraduate students at the University of Washington will be actively involved as part of this research and learn skills like hard tissue histology and CT data manipulation. Public engagement in Antarctic science will be accomplished at the University of Washington Burke Museum, which is the Washington State museum of natural history and culture. Specifically, a new exhibit on Antarctic amphibians will be developed as part of the paleontology gallery, which sees over 100,000 visitors per year. Technical Abstract This two-year project will examine the evolution of Triassic temnospondyls based on a remarkable collection of fossils recently recovered from the Shackleton Glacier region of Antarctica. Temnospondyls collected from the middle member of the Fremouw Formation are part of the first collection of identifiable tetrapod fossils from this stratigraphic interval. Thorough anatomical description and comparisons of these fossils will add new faunal information and also aid in determining if this horizon is Early or Middle Triassic in age. Exquisitely preserved temnospondyl material from the lower Fremouw Formation will permit more precise identification than previously possible and will provide insights into the earliest stages of their radiation in the extinction recovery interval. Overall, the Principal Investigator and Postdoctoral Researcher will spearhead an effort to revise the systematics of the Antarctic members of Temnospondyli and properly contextualize them in the framework of Triassic tetrapod evolution. The research team will also take advantage of the climate-sensitive nature of fossil amphibians to better understand patterns of seasonality at high-latitudes during the early Mesozoic by subjecting selected fossils to histological analysis. Preliminary data suggest that temnospondyls were exceptionally diverse and highly endemic immediately after the end-Permian extinction, when compared to their distribution before and after this interval. If confirmed, this macroevolutionary pattern could be used to predict the response of modern amphibians to future climate perturbations. Overall, this research will provide new insights into the vertebrate fauna of the Fremouw Formation, as well as shed light on the evolution of terrestrial ecosystems in southern Pangea in the wake of the Permian-Triassic mass extinction. As part of the broader impacts, the research team will help to develop an exhibit featuring some of the best preserved fossils from Antarctica to explain to the public how paleontologists use fossils and rocks to understand past climates like the Triassic \u0027hot-house\u0027 world that lacked permanent ice caps at the poles. 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": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Temnospondyls; MACROFOSSILS; USA/NSF; FIELD SURVEYS; Permian Extinction; Triassic; Amd/Us; USAP-DC; AMD; ANIMALS/VERTEBRATES; Shackleton Glacier", "locations": "Shackleton Glacier", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e PALEOZOIC \u003e PERMIAN", "persons": "Sidor, Christian", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "A non-amniote perspective on the recovery from the end-Permian extinction at high latitudes: paleobiology of Early Triassic temnospondyls from Antarctica", "uid": "p0010217", "west": null}, {"awards": "2027615 Paden, John", "bounds_geometry": null, "dataset_titles": "2022 Antarctica Ground; 2023 Antarctica Ground", "datasets": [{"dataset_uid": "200476", "doi": "", "keywords": null, "people": null, "repository": "CReSIS OPR", "science_program": null, "title": "2022 Antarctica Ground", "url": "https://data.cresis.ku.edu/data/accum/2022_Antarctica_Ground/"}, {"dataset_uid": "200477", "doi": "", "keywords": null, "people": null, "repository": "CReSIS OPR", "science_program": null, "title": "2023 Antarctica Ground", "url": "https://data.cresis.ku.edu/data/accum/2023_Antarctica_Ground/"}], "date_created": "Wed, 30 Jun 2021 00:00:00 GMT", "description": "This project will develop a new ice-penetrating radar system that can simultaneously map glacier geometry and glacier flow along repeat profiles. Forecasting an ice-sheet\u2019s contribution to sea level requires an estimate for the initial ice-sheet geometry and the parameters that govern ice flow and slip across bedrock. Existing ice-sheet models cannot independently determine this information from conventional observations of ice-surface velocities and glacier geometry. This introduces substantial uncertainty into simulations of past and future ice-sheet behavior. Thus, this new radar capability is conceived to provide the needed data to support higher-fidelity simulations of past and future ice-sheet behavior and more accurate projections of future sea level. The new radar system will integrate two existing radars (the multi-channel coherent radio-echo depth sounder and the accumulation radar) developed by the Center for the Remote Sensing of Ice Sheets, as well as adding new capabilities. An eight-element very high frequency (VHF; 140-215 MHz) array will have sufficient cross-track aperture to swath map internal layers and the ice-sheet base in three dimensions. A single ultra high frequency (UHF; 600-900 MHz) antenna will have the range and phase resolution to map internal layer displacement with 0.25-mm precision. The VHF array will create 3D mappings of layer geometry that enable measurements of vertical velocities by accounting for spatial offsets between repeat profiles and changing surface conditions. The vertical displacement measurement will then be made by determining the difference in radar phase response recorded by the UHF antenna for radar profiles collected at the same locations at different times. The UHF antenna will be dual-polarized and thus capable of isolating both components of complex internal reflections. This should enable inferences of ice crystal orientation fabric and widespread mapping of ice viscosity. Initial field testing of the radar will occur on the McMurdo Ice Shelf and then progress to Thwaites Glacier, Antarctica. The dual-band radar system technology and processing algorithms will be developed with versatile extensible hardware and user-friendly software so that this system will serve as a prototype for a future community radar system. 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": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e IMAGING RADAR SYSTEMS", "is_usap_dc": true, "keywords": "Amd/Us; USA/NSF; Airborne Radar; AMD; ICE SHEETS; Thwaites Glacier; USAP-DC; Eastwind Glacier", "locations": "Thwaites Glacier; Eastwind Glacier", "north": null, "nsf_funding_programs": "Antarctic Instrumentation and Facilities", "paleo_time": null, "persons": "Paden, John; Rodriguez-Morales, Fernando ; Christianson, Knut", "platforms": null, "repo": "CReSIS OPR", "repositories": "CReSIS OPR", "science_programs": "Thwaites (ITGC)", "south": null, "title": "Collaborative Research: EAGER: A Dual-Band Radar for Measuring Internal Ice Deformation: a Multipass Ice-Penetrating Radar Experiment on Thwaites Glacier and the McMurdo Ice Shelf", "uid": "p0010215", "west": null}, {"awards": "1341475 Smith, Nathan; 1341304 Sidor, Christian; 1341645 Makovicky, Peter; 2001033 Makovicky, Peter; 1341376 Tabor, Neil", "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": "1851022 Fudge, Tyler; 1851094 Baker, Ian", "bounds_geometry": null, "dataset_titles": "Code for calculating mean gradient for EDC sulfate data; EPICA Dome C Sulfate Data 7-3190m; Forward Diffusion Model used to calculate widening of volcanic layer widths; Volcanic Widths in Dome C Interglacials and Glacials", "datasets": [{"dataset_uid": "601855", "doi": "10.15784/601855", "keywords": "Antarctica; Cryosphere", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Volcanic Widths in Dome C Interglacials and Glacials", "url": "https://www.usap-dc.org/view/dataset/601855"}, {"dataset_uid": "601759", "doi": "10.15784/601759", "keywords": "Antarctica", "people": "Fudge, T. J.; Severi, Mirko", "repository": "USAP-DC", "science_program": "COLDEX", "title": "EPICA Dome C Sulfate Data 7-3190m", "url": "https://www.usap-dc.org/view/dataset/601759"}, {"dataset_uid": "601857", "doi": "10.15784/601857", "keywords": "Antarctica; Cryosphere", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Forward Diffusion Model used to calculate widening of volcanic layer widths", "url": "https://www.usap-dc.org/view/dataset/601857"}, {"dataset_uid": "601856", "doi": "10.15784/601856", "keywords": "Antarctica; Cryosphere", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Code for calculating mean gradient for EDC sulfate data", "url": "https://www.usap-dc.org/view/dataset/601856"}], "date_created": "Mon, 28 Jun 2021 00:00:00 GMT", "description": "The ice of the polar ice sheets is among the purest substances on Earth, yet the small amount of impurities --such as acids-- are important to how the ice flows and what can be learned from ice cores about past climate. The goal of this project is to understand the role of such acids on the deformation of polycrystalline ice by comparing the deformation behavior of pure and sulfuric acid-doped samples. Sulfuric acid was chosen both because of its importance for interpreting past climate and because it can lead to water veins in ice at low temperatures. This work will focus on the location, movement, and impact of acids in polycrystalline ice that are more complex than in single crystals of ice. By deforming samples and performing microstructural characterization, the role of acids on deformation rate, grain evolution, and the movement of the acids themselves, will be assessed. The work will lead to the education of a Ph.D. student at Dartmouth College, introduce undergraduate students to research at both the University of Washington and Dartmouth College. Despite the ubiquitous use of the constitutive relation for ice commonly referred to as \"Glen\u0027s Flow Law\", significant uncertainty exists particularly with regard to the role of impurities and the development of oriented fabrics. The aim of this project is to improve the constitutive relationship for ice by performing deformation tests and microstructural characterization of pure and sulfuric acid-doped ice. The project will focus on sulfuric acid\u0027s impact on ice viscosity, fabric evolution, and diffusivity. Sulfuric acid can have both direct and indirect effects on the mechanical properties of polycrystalline ice. The direct effects change the dislocation velocity and/or density, and the indirect effects change the grain size and fabric. The complexity and interaction of these effects means that it is not possible to understand the effects of sulfuric acid by simply examining ice core specimens. In this project, the team will deform four types of ice: lab-grown ice samples doped with similar-to-natural concentrations of sulfuric acid, lab-grown high-purity ice, layered doped and pure ice, and natural ice from Antarctic ice cores. Deformation will be performed in both uniaxial compression and simple shear. The addition of simple shear tests is critical for relating the laboratory-observed deformation behavior to the behavior of polar ice sheets where the shear strain dominates ice motion in basal ice. After deformation to strains from 5 percent up to 25 percent, the microstructural development will be assessed with methods including a variety of scanning electron microscope techniques, Raman microscopy, synchrotron-based Nano-X-ray fluorescence, and ion chromatography. These analysis techniques will allow the determination of 1) the segregation and movement of impurities, 2) the rate of grain-boundary migration, 3) the number of recrystallized grains; and 4) the full orientation of the ice crystals. The results will enable both microstructural modeling of the effects of sulfuric acid and numerical modeling of diffusion in ice cores. The net result will be a better understanding of ice deformation that improves ice-core interpretation and ice-sheet modeling. 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": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "AMD; Polycrystalline Ice; LABORATORY; Epica Dome C; SNOW/ICE; USA/NSF; USAP-DC; Ice Core; Amd/Us", "locations": "Epica Dome C", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Science and Technology; Antarctic Glaciology", "paleo_time": null, "persons": "Baker, Ian; Fudge, T. J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: The Impact of Impurities and Stress State on Polycrystalline Ice Deformation", "uid": "p0010211", "west": null}, {"awards": "1850988 Teets, Nicholas", "bounds_geometry": "POLYGON((-64.366767 -62.68104,-63.9917036 -62.68104,-63.6166402 -62.68104,-63.2415768 -62.68104,-62.8665134 -62.68104,-62.49145 -62.68104,-62.1163866 -62.68104,-61.7413232 -62.68104,-61.3662598 -62.68104,-60.9911964 -62.68104,-60.616133 -62.68104,-60.616133 -62.9537037,-60.616133 -63.2263674,-60.616133 -63.4990311,-60.616133 -63.7716948,-60.616133 -64.0443585,-60.616133 -64.3170222,-60.616133 -64.5896859,-60.616133 -64.8623496,-60.616133 -65.1350133,-60.616133 -65.407677,-60.9911964 -65.407677,-61.3662598 -65.407677,-61.7413232 -65.407677,-62.1163866 -65.407677,-62.49145 -65.407677,-62.8665134 -65.407677,-63.2415768 -65.407677,-63.6166402 -65.407677,-63.9917036 -65.407677,-64.366767 -65.407677,-64.366767 -65.1350133,-64.366767 -64.8623496,-64.366767 -64.5896859,-64.366767 -64.3170222,-64.366767 -64.0443585,-64.366767 -63.7716948,-64.366767 -63.4990311,-64.366767 -63.2263674,-64.366767 -62.9537037,-64.366767 -62.68104))", "dataset_titles": "Belgica antarctica collection sites - Summer 2023/2024 field season; Cold and dehydration tolerance of Belgica antarctica from three distinct geographic locations; Cross-tolerance in Belgica antarctica near Palmer Peninsula; Data from Edgington, H., Pavinato, V.A.C., Spacht, D., Gantz, J.D., Convey, P., Lee, R.E., Denlinger, D.L., Michel, A., 2023. Genetic history, structure and gene flow among populations of Belgica antarctica, the only free-living insect in the western Antarctic Peninsula. Polar Science 36, 100945.; Data from microplastics exposure in Belgica antarctica; Fine\u2011scale variation in microhabitat conditions influences physiology and metabolism in an Antarctic insect; Information on 2023 collection sites for Belgica antarctica; LMG2002 Expedtition Data; Long-term recovery from freezing in Belgica antarctica; Multiple stress tolerance in the Antarctic midge; Simulated winter warming negatively impacts survival of Antarcticas only endemic insect; Stress tolerance in Belgica antarctica and Eretmoptera murphyi; Temporal and spatial variation in stress tolerance in Belgica antarctica populations from distinct islands", "datasets": [{"dataset_uid": "200425", "doi": "", "keywords": null, "people": null, "repository": "USAP-DC", "science_program": null, "title": "Simulated winter warming negatively impacts survival of Antarcticas only endemic insect", "url": "https://www.usap-dc.org/view/dataset/601694"}, {"dataset_uid": "601875", "doi": null, "keywords": "Antarctica; Cryosphere", "people": "Michel, Andrew; Teets, Nicholas; Hayward, Scott; Sousa Lima, Cleverson", "repository": "USAP-DC", "science_program": null, "title": "Belgica antarctica collection sites - Summer 2023/2024 field season", "url": "https://www.usap-dc.org/view/dataset/601875"}, {"dataset_uid": "601873", "doi": null, "keywords": "Antarctica; Belgica Antarctica; Cryosphere; Population Genetics", "people": "Sousa Lima, Cleverson; Teets, Nicholas; Hayward, Scott; Michel, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Temporal and spatial variation in stress tolerance in Belgica antarctica populations from distinct islands", "url": "https://www.usap-dc.org/view/dataset/601873"}, {"dataset_uid": "200437", "doi": "", "keywords": null, "people": null, "repository": "USAP-DC", "science_program": null, "title": "Stress tolerance in Belgica antarctica and Eretmoptera murphyi", "url": "https://www.usap-dc.org/view/dataset/601874"}, {"dataset_uid": "200438", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "Data from Edgington, H., Pavinato, V.A.C., Spacht, D., Gantz, J.D., Convey, P., Lee, R.E., Denlinger, D.L., Michel, A., 2023. Genetic history, structure and gene flow among populations of Belgica antarctica, the only free-living insect in the western Antarctic Peninsula. Polar Science 36, 100945.", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA565153/"}, {"dataset_uid": "601872", "doi": "10.15784/601872", "keywords": "Antarctica; Belgica Antarctica; Cryosphere", "people": "Hayward, Scott; Sousa Lima, Cleverson; Michel, Andrew; Colinet, Herve; Teets, Nicholas", "repository": "USAP-DC", "science_program": null, "title": "Cross-tolerance in Belgica antarctica near Palmer Peninsula", "url": "https://www.usap-dc.org/view/dataset/601872"}, {"dataset_uid": "601871", "doi": null, "keywords": "Antarctica; Belgica Antarctica; Cryosphere", "people": "Gantz, Josiah D.; Sousa Lima, Cleverson; Michel, Andrew; Devlin, Jack; Hayward, Scott; Teets, Nicholas; Aquilino, Monica; Kawarasaki, Yuta; Pavinato, Vitor", "repository": "USAP-DC", "science_program": null, "title": "Stress tolerance in Belgica antarctica and Eretmoptera murphyi", "url": "https://www.usap-dc.org/view/dataset/601871"}, {"dataset_uid": "601867", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Cryosphere", "people": "Teets, Nicholas", "repository": "USAP-DC", "science_program": null, "title": "Multiple stress tolerance in the Antarctic midge", "url": "https://www.usap-dc.org/view/dataset/601867"}, {"dataset_uid": "601866", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Cryosphere", "people": "Teets, Nicholas; Devlin, Jack", "repository": "USAP-DC", "science_program": null, "title": "Data from microplastics exposure in Belgica antarctica", "url": "https://www.usap-dc.org/view/dataset/601866"}, {"dataset_uid": "601865", "doi": "10.15784/601865", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Seasonality", "people": "Gantz, Josiah D.; Teets, Nicholas; McCabe, Eleanor; Spacht, Drew; Devlin, Jack; Denlinger, David; Lee, Richard", "repository": "USAP-DC", "science_program": null, "title": "Fine\u2011scale variation in microhabitat conditions influences physiology and metabolism in an Antarctic insect", "url": "https://www.usap-dc.org/view/dataset/601865"}, {"dataset_uid": "601864", "doi": "10.15784/601864", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere", "people": "Teets, Nicholas; Kawarasaki, Yuta", "repository": "USAP-DC", "science_program": null, "title": "Cold and dehydration tolerance of Belgica antarctica from three distinct geographic locations", "url": "https://www.usap-dc.org/view/dataset/601864"}, {"dataset_uid": "601687", "doi": "10.15784/601687", "keywords": "Antarctica; Antarctic Peninsula; Belgica Antarctica; Biota; Sample Location", "people": "Sousa Lima, Cleverson; Pavinato, Vitor; Gantz, Joseph; Kawarasaki, Yuta; Devlin, Jack; Teets, Nicholas; Michel, Andrew; Peter, Convey", "repository": "USAP-DC", "science_program": null, "title": "Information on 2023 collection sites for Belgica antarctica", "url": "https://www.usap-dc.org/view/dataset/601687"}, {"dataset_uid": "601698", "doi": "10.15784/601698", "keywords": "Antarctica; Belgica Antarctica; Palmer Station", "people": "Lecheta, Melise; Devlin, Jack; Teets, Nicholas; Sousa Lima, Cleverson", "repository": "USAP-DC", "science_program": null, "title": "Long-term recovery from freezing in Belgica antarctica", "url": "https://www.usap-dc.org/view/dataset/601698"}, {"dataset_uid": "200222", "doi": "10.7284/908802", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "LMG2002 Expedtition Data", "url": "https://www.rvdata.us/search/cruise/LMG2002"}], "date_created": "Fri, 25 Jun 2021 00:00:00 GMT", "description": "The cold, dry terrestrial environments of Antarctica are inhospitable for insects, and only three midge species make Antarctica home. Of these, Belgica antarctica is the only species found exclusively in Antarctica, and it has been a resident of Antarctica since the continent split from South America ~30 million years ago. Thus, this species is an excellent system to model the biological history of Antarctica throughout its repeated glaciation events and shifts in climate. This insect is also a classic example of extreme adaptation, and much previous work has focused on identifying the genetic and physiological mechanisms that allow this species to survive where no other insect is capable. However, it has been difficult to pinpoint the unique evolutionary adaptations that are required to survive in Antarctica due to a lack of information from closely related Antarctic and sub-Antarctic species. This project will compare adaptations, genome sequences, and population characteristics of four midge species that span an environmental gradient from sub-Antarctic to Antarctic habitats. In addition to B. antarctica, these species include two species that are strictly sub-Antarctic and a third that is native to the sub-Antarctic but has invaded parts of Antarctica. The researchers, comprised of scientists from the US, UK, Chile, and France, will sample insects from across their geographic range and measure their ability to tolerate environmental stressors (i.e., cold and desiccation), quantify molecular responses to stress, and compare the makeup of the genome and patterns of genetic diversity. This research will contribute to a greater understanding of adaptation to extremes, to an understanding of biodiversity on the planet and to understanding and predicting changes accompanying environmental change. The project will train two graduate students and two postdoctoral researchers, and a K-12 educator will be a member of the field team and will assist with fieldwork and facilitate outreach with schools in the US. The project includes partnership activities with several STEM education organizations to deliver educational content to K-12 and secondary students. This is a project that is jointly funded by the National Science Foundation\u0027s Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Each Agency funds the proportion of the budget and the investigators associated with its own country. UK participation in this project includes deploying scientists as part of the field team, supporting field and sampling logistics at remote Antarctic sites, and genome sequencing, annotation, and analyses. This project focuses on the key physiological adaptations and molecular processes that allow a select few insect species to survive in Antarctica. The focal species are all wingless with limited dispersal capacity, suggesting there is also significant potential to locally adapt to variable environmental conditions across the range of these species. The central hypothesis is that similar molecular mechanisms drive both population-level adaptation to local environmental conditions and macroevolutionary changes across species living in different environments. The specific aims of the project are to 1) Characterize conserved and species-specific adaptations to extreme environments through comparative physiology and transcriptomics, 2) Compare the genome sequences of these species to identify genetic signatures of extreme adaption, and 3) Investigate patterns of diversification and local adaptation across each species? range using population genomics. The project establishes an international collaboration of researchers from the US, UK, Chile, and France with shared interests and complementary expertise in the biology, genomics, and conservation of Antarctic arthropods. The Broader Impacts of the project include training students and partnering with the Living Arts and Science Center to design and implement educational content for K-12 students. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -60.616133, "geometry": "POINT(-62.49145 -64.0443585)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; Livingston Island; Antarctica; USAP-DC; AMD; R/V LMG; USA/NSF; ARTHROPODS; Amd/Us; Anvers Island", "locations": "Antarctica; Antarctic Peninsula; Anvers Island; Livingston Island", "north": -62.68104, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Teets, Nicholas; Michel, Andrew", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "USAP-DC", "repositories": "NCBI; R2R; USAP-DC", "science_programs": null, "south": -65.407677, "title": "NSFGEO-NERC: Mechanisms of Adaptation to Terrestrial Antarctica through Comparative Physiology and Genomics of Antarctic and sub-Antarctic Insects", "uid": "p0010203", "west": -64.366767}, {"awards": "1744970 Shevenell, Amelia", "bounds_geometry": "POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.1,121 -66.2,121 -66.3,121 -66.4,121 -66.5,121 -66.6,121 -66.7,121 -66.8,121 -66.9,121 -67,120.9 -67,120.8 -67,120.7 -67,120.6 -67,120.5 -67,120.4 -67,120.3 -67,120.2 -67,120.1 -67,120 -67,120 -66.9,120 -66.8,120 -66.7,120 -66.6,120 -66.5,120 -66.4,120 -66.3,120 -66.2,120 -66.1,120 -66))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 22 Jun 2021 00:00:00 GMT", "description": "Glacial retreat in West Antarctica is correlated with ocean warming; however, less is known about the ocean\u0027s effect on East Antarctica\u0027s glaciers including Totten Glacier located on the Sabrina Coast. The retreat of Totten Glacier has global significance as the glacier drains a sector of the East Antarctic Ice Sheet that contains enough ice to raise global sea levels by as much as 3.5 meters. This study looks to determine the influence of ocean temperatures on East Antarctic glaciers, including Totten Glacier, over the last ~18,000 years by studying seafloor sediment around Antarctica. These sediments, or muds, include the remains of microscopic marine organisms as well as tiny particles originating from eroded Antarctic bedrock. These muds provide a record of past environmental changes including ocean temperatures and the advance and retreat of glaciers. Scientists use a variety of physical and chemical analyses to determine how long ago this mud was deposited, the temperature of the ocean at that location through time, and the relative location of glacial ice. In this project, researchers will refine and test new methods for measuring ocean temperature from the sediments to better understand the influence of ocean temperatures on East Antarctic glacier response. Results will be integrated into ice sheet and climate models to improve the accuracy of ice sheet modeling efforts and subsequent sea level predictions. Results from this project will be disseminated at scientific conferences, in the scientific literature, and more broadly to the general public via the St. Petersburg Science Festival and at the Oceanography Camp for Girls. The influence of ocean temperatures on East Antarctic glaciers is largely unknown. This research focuses on ice-proximal Antarctic margin paleoceanographic proxy calibration and validation, which will improve understanding of past ocean-ice sheet interactions on a variety of timescales. In this project, researchers from the University of South Florida will (1) further develop and refine two ocean temperature proxies, foraminifer Mg/Ca and TEX86, for use in ice-proximal Antarctic continental margin sediments and (2) investigate deglacial to present (~18-0 ka) ocean-ice interactions at the outlet of the climatically sensitive Aurora Subglacial Basin. The proposed research utilizes sediment trap, sediment core, and physical oceanographic data previously collected from the Sabrina Coast continental shelf during NSF-funded cruise NBP14-02. Studies of existing sediment cores will integrate multiple paleotemperature, meltwater/salinity, nutrient, bottom water oxygen, and sea ice proxies with geophysical and lithologic data to understand past regional ocean-ice interactions. While the recent international Antarctic research focus has been on understanding the drivers of West Antarctic Ice Sheet retreat, models suggest it would be imprudent to ignore the East Antarctic Ice Sheet, which is proving more sensitive to climate perturbations than previously realized. 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": 121.0, "geometry": "POINT(120.5 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "SEDIMENTS; FIELD INVESTIGATION; USA/NSF; USAP-DC; PALEOCLIMATE RECONSTRUCTIONS; Sabrina Coast; AMD; Amd/Us", "locations": "Sabrina Coast", "north": -66.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Shevenell, Amelia", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": -67.0, "title": "Deglacial to Recent Paleoceanography of the Sabrina Coast, East Antarctica: A Multi-proxy Study of Ice-ocean Interactions at the Outlet of the Aurora Subglacial Basin", "uid": "p0010194", "west": 120.0}, {"awards": "1852617 Carlstrom, John", "bounds_geometry": "POINT(0 -90)", "dataset_titles": null, "datasets": null, "date_created": "Tue, 11 May 2021 00:00:00 GMT", "description": "This award is to support measurements of the 14-billion-year cosmic microwave background (CMB) light with the South Pole Telescope (SPT) to address some of the most basic and compelling questions in cosmology: What is the origin of the Universe? What is the Universe made of? What is the mass scale of the neutrinos? When did the first stars and galaxies form and how was the Universe reionized? What is the Dark Energy that is accelerating the expansion of the Universe? The SPT plays a unique role in the pursuit of these questions. Its siting is ideal for ultra-low-noise imaging surveys of the sky at the millimeter and sub-millimeter radio wavelengths. The SPT is supported by the NSF\u0027s Amundsen-Scott South Pole Station, which is the best operational site on Earth for mm-wave sky surveys. This unique geographical location allows SPT to obtain extremely sensitive 24/7 observations of targeted low Galactic foreground regions of the sky. The telescope\u0027s third-generation, SPT-3G receiver has 16,000 detectors configured for polarization-sensitive observations in three millimeter-wave bands. The proposed operation includes five years of sky surveys to obtain ultra-deep measurements of a 1500 square degree field and to produce and publicly archive essential data products from the survey. The telescope\u0027s CMB temperatures and polarization power spectrum will play a central role in probing the nature of current tensions among cosmological parameter estimations from different data sets and determining if their explanation requires physics beyond the current LCDM model. The data will help constraining the Dark Energy properties that affect the growth of large structures through both the CMB lensing and abundance of galaxy clusters. The proposed operations also support SPT\u0027s critical role in the Event Horizon Telescope (EHT), a global array of telescopes to image the event horizon around the black hole at the center of Milky Way Galaxy. This award addresses and advances the science objectives and goals of the NSF\u0027s \"Windows on the Universe: The Era of Multi-Messenger Astrophysics\" program. The proposed research activity will also contribute to the training of the next generation of scientists by integrating graduate and undergraduate education with the technology development, astronomical observations, and scientific analyses of SPT data. Research and education are integrated by bringing research activities into the undergraduate classroom and sharing of forefront research with non-scientists extending it beyond the university through a well-established educational network that reaches a wide audience at all levels of the educational continuum. Through museum partnerships and new media, the SPT outreach and educational efforts reach large numbers of individuals while personalizing the experience. 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": 0.0, "geometry": "POINT(0 -90)", "instruments": "SOLAR/SPACE OBSERVING INSTRUMENTS \u003e RADIO WAVE DETECTORS \u003e RADIO TELESCOPES", "is_usap_dc": true, "keywords": "USAP-DC; AMD; Adelie Penguin; THERMAL INFRARED; South Pole Station; Amd/Us; OBSERVATORIES", "locations": "South Pole Station", "north": -90.0, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences; Antarctic Science and Technology; Polar Special Initiatives", "paleo_time": null, "persons": "Carlstrom, John; Holzapfel, William; Benson, Bradford", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e OBSERVATORIES", "repositories": null, "science_programs": null, "south": -90.0, "title": "South Pole Telescope Operations and Data Products", "uid": "p0010176", "west": 0.0}, {"awards": "1543459 Dugger, Katie; 1543498 Ballard, Grant; 1543541 Ainley, David", "bounds_geometry": "POLYGON((-180 -60,-177 -60,-174 -60,-171 -60,-168 -60,-165 -60,-162 -60,-159 -60,-156 -60,-153 -60,-150 -60,-150 -61.8,-150 -63.6,-150 -65.4,-150 -67.2,-150 -69,-150 -70.8,-150 -72.6,-150 -74.4,-150 -76.2,-150 -78,-153 -78,-156 -78,-159 -78,-162 -78,-165 -78,-168 -78,-171 -78,-174 -78,-177 -78,180 -78,178.5 -78,177 -78,175.5 -78,174 -78,172.5 -78,171 -78,169.5 -78,168 -78,166.5 -78,165 -78,165 -76.2,165 -74.4,165 -72.6,165 -70.8,165 -69,165 -67.2,165 -65.4,165 -63.6,165 -61.8,165 -60,166.5 -60,168 -60,169.5 -60,171 -60,172.5 -60,174 -60,175.5 -60,177 -60,178.5 -60,-180 -60))", "dataset_titles": "Adelie penguin banding data 1994-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science; Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science; Locations of Adelie penguins from geolocating dive recorders 2017-2019; Penguinscience Data Sharing Website", "datasets": [{"dataset_uid": "601482", "doi": "10.15784/601482", "keywords": "Adelie Penguin; Animal Behavior Observation; Antarctica; Biologging; Biota; Foraging Ecology; Geolocator; GPS Data; Migration; Ross Sea; Winter", "people": "Lescroel, Amelie; Ainley, David; Schmidt, Annie; Ballard, Grant; Lisovski, Simeon; Dugger, Katie", "repository": "USAP-DC", "science_program": null, "title": "Locations of Adelie penguins from geolocating dive recorders 2017-2019", "url": "https://www.usap-dc.org/view/dataset/601482"}, {"dataset_uid": "200278", "doi": "", "keywords": null, "people": null, "repository": "California Avian Data Center", "science_program": null, "title": "Penguinscience Data Sharing Website", "url": "https://data.pointblue.org/apps/penguin_science/"}, {"dataset_uid": "601443", "doi": "10.15784/601443", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Penguin; Ross Sea; Seabirds", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin banding data 1994-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601443"}, {"dataset_uid": "601444", "doi": "10.15784/601444", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Mark-Recapture; Monitoring; Penguin; Ross Island", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601444"}], "date_created": "Tue, 11 May 2021 00:00:00 GMT", "description": "The Ross Sea region of the Southern Ocean is experiencing growing sea ice cover in both extent and duration. These trends contrast those of the well-studied, western Antarctic Peninsula area, where sea ice has been disappearing. Unlike the latter, little is known about how expanding sea ice coverage might affect the regional Antarctic marine ecosystem. This project aims to better understand some of the potential effects of the changing ice conditions on the marine ecosystem using the widely-recognized indicator species - the Ad\u00e9lie Penguin. A four-year effort will build on previous results spanning 19 seasons at Ross Island to explore how successes or failures in each part of the penguin\u0027s annual cycle are effected by ice conditions and how these carry over to the next annual recruitment cycle, especially with respect to the penguin\u0027s condition upon arrival in the spring. Education and public outreach activities will continually be promoted through the PenguinCam and PenguinScience websites (sites with greater than 1 million hits a month) and \"NestCheck\" (a site that is logged-on by \u003e300 classrooms annually that allows students to follow penguin families in their breeding efforts). To encourage students in pursuing educational and career pathways in the Science Technology Engineering and Math fields, the project will also provide stories from the field in a Penguin Journal, develop classroom-ready activities aligned with New Generation Science Standards, increase the availability of instructional presentations as powerpoint files and short webisodes. The project will provide additional outreach activities through local, state and national speaking engagements about penguins, Antarctic science and climate change. The annual outreach efforts are aimed at reaching over 15,000 students through the website, 300 teachers through presentations and workshops, and 500 persons in the general public. The project also will train four interns (undergraduate and graduate level), two post-doctoral researchers, and a science writer/photographer. The project will accomplish three major goals, all of which relate to how Ad\u00e9lie Penguins adapt to, or cope with environmental change. Specifically the project seeks to determine 1) how changing winter sea ice conditions in the Ross Sea region affect penguin migration, behavior and survival and alter the carry-over effects (COEs) to subsequent reproduction; 2) the interplay between extrinsic and intrinsic factors influencing COEs over multiple years of an individual?s lifetime; and 3) how local environmental change may affect population change via impacts to nesting habitat, interacting with individual quality and COEs. Retrospective analyses will be conducted using 19 years of colony based data and collect additional information on individually marked, known-age and known-history penguins, from new recruits to possibly senescent individuals. Four years of new information will be gained from efforts based at two colonies (Cape Royds and Crozier), using radio frequency identification tags to automatically collect data on breeding and foraging effort of marked, known-history birds to explore penguin response to resource availability within the colony as well as between colonies (mates, nesting material, habitat availability). Additional geolocation/time-depth recorders will be used to investigate travels and foraging during winter of these birds. The combined efforts will allow an assessment of the effects of penguin behavior/success in one season on its behavior in the next (e.g. how does winter behavior affect arrival time and body condition on subsequent breeding). It is at the individual level that penguins are responding successfully, or not, to ongoing marine habitat change in the Ross Sea region.", "east": -150.0, "geometry": "POINT(-172.5 -69)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; AMD; Adelie Penguin; Amd/Us; FIELD INVESTIGATION; MARINE ECOSYSTEMS; Ross Island; USAP-DC; Penguin", "locations": "Ross Island", "north": -60.0, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ballard, Grant; Ainley, David; Dugger, Katie", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "California Avian Data Center; USAP-DC", "science_programs": null, "south": -78.0, "title": "A Full Lifecycle Approach to Understanding Ad\u00e9lie Penguin Response to Changing Pack Ice Conditions in the Ross Sea.", "uid": "p0010177", "west": 165.0}, {"awards": "1643652 Hofmann, Eileen; 1643618 Arrigo, Kevin", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic biological model output; Antarctic dFe model dyes", "datasets": [{"dataset_uid": "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"}, {"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"}], "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": "1600823 Halzen, Francis; 2042807 Halzen, Francis; 0639286 Halzen, Francis; 0937462 Halzen, Francis", "bounds_geometry": "POINT(-180 -90)", "dataset_titles": "Amanda 7 Year Data Set; IceCube data releases", "datasets": [{"dataset_uid": "200374", "doi": "", "keywords": null, "people": null, "repository": "IceCube", "science_program": null, "title": "IceCube data releases", "url": "https://icecube.wisc.edu/science/data-releases/"}, {"dataset_uid": "601438", "doi": "10.15784/601438", "keywords": "Amanda-ii; Antarctica; Neutrino; Neutrino Candidate Events; Neutrino Telescope; South Pole", "people": "Halzen, Francis; Riedel, Benedikt", "repository": "USAP-DC", "science_program": "IceCube", "title": "Amanda 7 Year Data Set", "url": "https://www.usap-dc.org/view/dataset/601438"}], "date_created": "Wed, 07 Apr 2021 00:00:00 GMT", "description": "This award funds the continued management and operations (M\u0026O) of the IceCube Neutrino Observatory (ICNO) located at the South Pole Station. The core team of researchers and engineers maintain the existing ICNO infrastructure at the South Pole and home institution, guaranteeing an uninterrupted stream of scientifically unique, high-quality data. The M\u0026O activities are built upon eight highly successful years of managing the overall ICNO operations after the start of science operations in 2008. Construction of ICNO was supported by NSF\u0027s Major Research Equipment and Facilities Construction (MREFC) account and was completed on schedule and within budget in 2010. Effective coordination of efforts by the core M\u0026O personnel and efforts by personnel within the IceCube Collaboration has yielded significant increases in the performance of this cubic-kilometer detector over time. The scientific output from the IceCube Collaboration during the past five years has been outstanding. The broader impacts of the ICNO/M\u0026O activities are strong, involving postdoctoral, graduate, and (in some cases) undergraduate students in the day-today operation \u0026 calibration of the neutrino detector. The extraordinary physics results recently produced by ICNO and its extraordinary location at South Pole have a high potential to excite the imagination of high school children and the public in general at a national and international level. The current ICNO/M\u0026O effort produces better energy and angular resolution information about detected neutrino events, has more efficient data filters and more accurate detector simulations, and enables continuous software development for systems that are needed to acquire and analyze data. This has produced data acquisition and data management systems with high robustness, traceability, and maintainability. The current ICNO/M\u0026O effort includes: (1) resources for both distributed and centrally managed activities, and (2) additional accountability mechanisms for \"in-kind\" and institutional contributions. Both are necessary to ensure that the detector maintains its capability to produce quality scientific data at the level required to achieve the detector\u0027s scientific discovery objectives. Recent ICNO discoveries of cosmic high-energy neutrinos (some reaching energies close to and over 2.5 PeV) and oscillating atmospheric neutrinos in a previously unexplored energy range from 10 to 60 GeV became possible because of the \"state-of-the-art\" detector configuration, excellently supported infrastructure, and cutting-edge science analyses. The ICNO has set limits on Dark Matter annihilations, made precision measurements of the angular distribution of cosmic ray muons, and characterized in detail physical properties of the Antarctic 2.5-km thick ice sheet at South Pole. The discovery of high-energy cosmic neutrinos by IceCube with a flux at the level anticipated for those associated with high-energy gamma- and cosmic-ray accelerators brightens the prospect for identifying the sources of the highest energy particles.", "east": -180.0, "geometry": "POINT(-180 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e ICECUBE", "is_usap_dc": true, "keywords": "USA/NSF; South Pole; OBSERVATORIES; Amd/Us; AMD; GLACIERS/ICE SHEETS; Icecube; Neutrino; USAP-DC", "locations": "South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences; Antarctic Astrophysics and Geospace Sciences; Antarctic Astrophysics and Geospace Sciences; Antarctic Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Halzen, Francis; Karle, Albrecht", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e OBSERVATORIES", "repo": "IceCube", "repositories": "IceCube; USAP-DC", "science_programs": "IceCube", "south": -90.0, "title": "Management and Operations of the IceCube Neutrino Observatory 2021-2026", "uid": "p0010168", "west": -180.0}, {"awards": "1443525 Schwartz, Susan", "bounds_geometry": "POLYGON((-165 -83.8,-163 -83.8,-161 -83.8,-159 -83.8,-157 -83.8,-155 -83.8,-153 -83.8,-151 -83.8,-149 -83.8,-147 -83.8,-145 -83.8,-145 -83.92,-145 -84.04,-145 -84.16,-145 -84.28,-145 -84.4,-145 -84.52,-145 -84.64,-145 -84.76,-145 -84.88,-145 -85,-147 -85,-149 -85,-151 -85,-153 -85,-155 -85,-157 -85,-159 -85,-161 -85,-163 -85,-165 -85,-165 -84.88,-165 -84.76,-165 -84.64,-165 -84.52,-165 -84.4,-165 -84.28,-165 -84.16,-165 -84.04,-165 -83.92,-165 -83.8))", "dataset_titles": "YD (2012-2017): Whillians Ice Stream Subglacial Access Research Drilling", "datasets": [{"dataset_uid": "200201", "doi": "https://doi.org/10.7914/SN/YD_2012", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "YD (2012-2017): Whillians Ice Stream Subglacial Access Research Drilling", "url": "http://www.fdsn.org/networks/detail/YD_2012/"}], "date_created": "Fri, 12 Feb 2021 00:00:00 GMT", "description": "This project evaluates the role that water and rock/ice properties at the base of a fast moving glacier, or ice stream, play in controlling its motion. In Antarctica, where surface melting is limited, the speed of ice flow through the grounding zone (where ice on land detaches, and begins to float on ocean water) controls the rate at which glaciers contribute to sea level rise. The velocity of the ice stream is strongly dependent on resistance from the bed, so understanding the processes that control resistance to flow is critical in predicting ice sheet mass balance. In fact, the Intergovernmental Panel on Climate Change (IPCC) recognized this and stated in their 4th assessment report that reliable predictions of future global sea-level rise require improved understanding of ice sheet dynamics, which include basal controls on fast ice motion. Drilling to obtain direct observations of basal properties over substantial regions is prohibitively expensive. This project uses passive source seismology to \"listen to\" and analyze sounds generated by water flow and/or sticky spots at the ice/bed interface to evaluate the role that basal shear stress plays in ice flow dynamics. Because polar science is captivating to both scientists and the general public, it serves as an excellent topic to engage students at all levels with important scientific concepts and processes. In conjunction with this research, polar science educational materials will be developed to be used by students spanning middle school through the University level. Starting in summer 2015, a new polar science class for high school students in the California State Summer School for Mathematics and Science (COSMOS) will be offered at the University of California-Santa Cruz. This curriculum will be shared with the MESA Schools Program, a Santa Cruz and Monterey County organization that runs after-school science clubs led by teachers at several local middle and high schools with largely minority and underprivileged populations. This proposal extends the period of borehole and surface geophysical monitoring of the Whillians Ice Stream (WIS) established under a previous award for an additional 2 years. Data from the WIS network demonstrated that basal heterogeneity, revealed by microseismicity, shows variation over scales of 100\u0027s of meters. An extended observation period will allow detailed seismic characterization of ice sheet bed properties over a crucial length scale comparable to the local ice thickness. Due to the fast ice velocity (\u003e300 m/year), a single instrumented location will move approximately 1 km during the extended 3 year operational period, allowing continuous monitoring of seismic emissions as the ice travels over sticky spots and other features in the bed (e.g., patches of till or subglacial water bodies). Observations over ~1km length scales will help to bridge a crucial gap in current observations of basal conditions between extremely local observations made in boreholes and remote observations of basal shear stress inferred from inversions of ice surface velocity data.", "east": -145.0, "geometry": "POINT(-155 -84.4)", "instruments": null, "is_usap_dc": true, "keywords": "Whillans Ice Stream; GLACIERS/ICE SHEETS; FIELD INVESTIGATION", "locations": "Whillans Ice Stream", "north": -83.8, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Tulaczyk, Slawek; Schwartz, Susan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "IRIS", "repositories": "IRIS", "science_programs": "WISSARD", "south": -85.0, "title": "High Resolution Heterogeneity at the Base of Whillans Ice Stream and its Control on Ice Dynamics", "uid": "p0010159", "west": -165.0}, {"awards": "1443144 Steig, Eric; 1443448 Schaefer, Joerg", "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": "Simulations of 10Be over Antarctica; South Pole ice Core 10Be CE", "datasets": [{"dataset_uid": "601431", "doi": "10.15784/601431", "keywords": "Antarctica; South Pole", "people": "Steig, Eric J.; Ding, Qinghua; Schaefer, Joerg", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Simulations of 10Be over Antarctica", "url": "https://www.usap-dc.org/view/dataset/601431"}, {"dataset_uid": "601535", "doi": "10.15784/601535", "keywords": "Antarctica; South Pole", "people": "Schaefer, Joerg", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice Core 10Be CE", "url": "https://www.usap-dc.org/view/dataset/601535"}], "date_created": "Thu, 04 Feb 2021 00:00:00 GMT", "description": "This project will acquire measurements of the concentration of beryllium-10 (10Be) from an ice core from the South Pole, Antarctica. An isotope of the element beryllium, 10Be, is produced in the atmosphere by high-energy protons (cosmic rays) that enter Earth\u0027s atmosphere from space. It is removed from the atmosphere by settling or by scavenging by rain or snowfall. Hence, concentrations of 10Be in snow at the South Pole reflect the production rate of 10Be in the atmosphere. Because the rate of production of 10Be over Antarctica depends primarily on the strength of the Sun\u0027s magnetic field, measurements of 10Be in the South Pole ice core will provide a record of changes in solar activity. The South Pole ice core will reach an age of 40,000 years at the bottom. The project will result in measurements of 10Be at annual resolution for the last 100 years and selected periods in the more distant past, such as the Maunder Minimum, a period during the late 17th century during which no sunspots were observed, or the last glacial cold period, about 20,000 years ago. A climate model that can simulate the production of 10Be in the atmosphere, it\u0027s transport through the atmosphere, and its deposition at the snow surface in Antarctica will be used to aid in using the 10Be data to determine past changes in solar activity from decadal to millennial scale, and in turn to evaluate the role of the Sun in Earth?s climate from a new perspective. The production of 10Be in Earth\u0027s atmosphere results from the spallation of oxygen and nitrogen in the atmosphere by cosmic rays. Cosmic ray variations in the high latitudes are primarily modulated by solar variability. Time-series records of 10Be from ice cores are therefore important for deriving variations in solar activity through time, which is fundamental to understanding climate variability. Deposition of 10Be to the ice surface is also influenced by variability in atmospheric circulation and deposition processes, and South Pole is the best available location for minimizing the influence of variable atmospheric circulation on 10Be deposition. To date, only one record of 10Be exists from South Pole; that record is widely used in solar forcing estimates used in climate models, but covers only the last millennium and ends in CE 1982. We will obtain 10Be concentration measurements in a 1500-m, 40000-year long ice core from the South Pole. This will extend the existing record both further back in time and forward to the present, providing overlap with the modern instrumental record of solar and climate variability. High resolution (annual to biannual) measurements will be made in targeted areas of interest, including the last 100 years, the Maunder Minimum (CE 1650-1715), and the last glacial maximum. The novel data will be used in conjunction with climate model experiments that incorporate 10Be production, transport, and deposition physics. Together, data and modeling will create an updated record of atmospheric 10Be production and hence of solar activity.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "COSMIC RAYS; LABORATORY; BERYLLIUM-10 ANALYSIS; SNOW/ICE; South Pole; GLACIERS; ICE CORE RECORDS", "locations": "South Pole", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Schaefer, Joerg; Steig, Eric J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: A High-sensitivity Beryllium-10 Record from an Ice Core at South Pole", "uid": "p0010158", "west": -180.0}, {"awards": "0838783 Conway, Howard; 0838256 Todd, Claire; 0838784 Balco, Gregory", "bounds_geometry": "POLYGON((-66.27517 -83.23921,-65.341961 -83.23921,-64.408752 -83.23921,-63.475543 -83.23921,-62.542334 -83.23921,-61.609125 -83.23921,-60.675916 -83.23921,-59.742707 -83.23921,-58.809498 -83.23921,-57.876289 -83.23921,-56.94308 -83.23921,-56.94308 -83.359865,-56.94308 -83.48052,-56.94308 -83.601175,-56.94308 -83.72183,-56.94308 -83.842485,-56.94308 -83.96314,-56.94308 -84.083795,-56.94308 -84.20445,-56.94308 -84.325105,-56.94308 -84.44576,-57.876289 -84.44576,-58.809498 -84.44576,-59.742707 -84.44576,-60.675916 -84.44576,-61.609125 -84.44576,-62.542334 -84.44576,-63.475543 -84.44576,-64.408752 -84.44576,-65.341961 -84.44576,-66.27517 -84.44576,-66.27517 -84.325105,-66.27517 -84.20445,-66.27517 -84.083795,-66.27517 -83.96314,-66.27517 -83.842485,-66.27517 -83.72183,-66.27517 -83.601175,-66.27517 -83.48052,-66.27517 -83.359865,-66.27517 -83.23921))", "dataset_titles": "Interface to observational data collected in this project and geologic age information derived therefrom. Dynamic content, continuously updated.; Web page linking to documents containing data collected in this project. Static content", "datasets": [{"dataset_uid": "200194", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Interface to observational data collected in this project and geologic age information derived therefrom. Dynamic content, continuously updated.", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200195", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Web page linking to documents containing data collected in this project. Static content", "url": "http://noblegas.berkeley.edu/~balcs/pensacola/"}], "date_created": "Sat, 19 Dec 2020 00:00:00 GMT", "description": "This award supports a project to find and date geologic evidence of past ice-marginal positions in the Pensacola Mountains, which border the Foundation Ice Stream at the head of the Weddell Sea embayment. The project will involve glacial geologic mapping and cosmogenic-nuclide surface exposure dating of glacially transported erratics. An ice-flow model will be used to link our exposure-dating results together in a glaciologically consistent way, and to relate them to regional LGM to Holocene elevation changes. A secondary focus of the project seeks to improve the effectiveness of exposure-dating methods in understanding ice sheet change. Changes in the location of the ice margin, and thus the exposure ages that record these changes, are controlled not only by regional ice sheet mass balance, but also by local effects on snow- and icefields immediately adjacent to the exposure-dating sites. This part of the project will combine glaciological observations near the present ice margin with targeted exposure- age sampling in an effort to better understand the processes controlling the ice margin location, and improve the interpretation of very recent exposure-age data as a record of latest Holocene to present ice sheet changes. The intellectual merit of the project is that it will provide direct geologic evidence of LGM-to-Holocene ice volume change in a region of Antarctica where no such evidence now exists. The broader impacts of the work involve both gathering information needed for accurate understanding of past and present global sea level change. Secondly, this project will help to develop and maintain the human and intellectual resources necessary for continued excellence in polar research and global change education, by linking experienced Antarctic researchers with early career scientists who seek to develop their expertise in both research and education. In addition, it brings together two early career scientists whose careers are focused at opposite ends of the research-education spectrum, thus facilitating better integration of research and education both in the careers of these scientists and in the outcome of this project. This award has field work in Antarctica.", "east": -56.94308, "geometry": "POINT(-61.609125 -83.842485)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; GLACIER THICKNESS/ICE SHEET THICKNESS; NOT APPLICABLE; GLACIER ELEVATION/ICE SHEET ELEVATION; Antarctica", "locations": "Antarctica", "north": -83.23921, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Balco, Gregory; Todd, Claire; Conway, Howard", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "ICE-D", "repositories": "ICE-D; PI website", "science_programs": null, "south": -84.44576, "title": "Collaborative Research: Last Glacial Maximum and Deglaciation Chronology for the Foundation Ice Stream and Southeastern Weddell Sea Embayment", "uid": "p0010151", "west": -66.27517}, {"awards": "1644196 Cziko, Paul", "bounds_geometry": "POLYGON((163.47 -77.14,163.803 -77.14,164.136 -77.14,164.469 -77.14,164.802 -77.14,165.135 -77.14,165.468 -77.14,165.801 -77.14,166.134 -77.14,166.467 -77.14,166.8 -77.14,166.8 -77.216,166.8 -77.292,166.8 -77.368,166.8 -77.444,166.8 -77.52,166.8 -77.596,166.8 -77.672,166.8 -77.748,166.8 -77.824,166.8 -77.9,166.467 -77.9,166.134 -77.9,165.801 -77.9,165.468 -77.9,165.135 -77.9,164.802 -77.9,164.469 -77.9,164.136 -77.9,163.803 -77.9,163.47 -77.9,163.47 -77.824,163.47 -77.748,163.47 -77.672,163.47 -77.596,163.47 -77.52,163.47 -77.444,163.47 -77.368,163.47 -77.292,163.47 -77.216,163.47 -77.14))", "dataset_titles": "High-resolution nearshore benthic seawater temperature from around McMurdo Sound, Antarctica (2017-2019); Long-Term broadband underwater acoustic recordings from McMurdo Sound, Antarctica (2017-2019); Long-term underwater images from around a single mooring site in McMurdo Sound, Antarctica (2017-2019)", "datasets": [{"dataset_uid": "601420", "doi": "10.15784/601420", "keywords": "Antarctica; Benthic Ecology; CTD; Depth; McMurdo Sound; Oceanography; Oceans; Physical Oceanography; Pressure; Salinity; Seawater Measurements; Seawater Temperature; Supercooling; Tides", "people": "Cziko, Paul", "repository": "USAP-DC", "science_program": null, "title": "High-resolution nearshore benthic seawater temperature from around McMurdo Sound, Antarctica (2017-2019)", "url": "https://www.usap-dc.org/view/dataset/601420"}, {"dataset_uid": "601416", "doi": "10.15784/601416", "keywords": "Antarctica; Bioacoustics; Biota; Hydroacoustics; Killer Whales; Leptonychotes Weddellii; McMurdo Sound; Oceans; Orcinus Orca; Sea Ice; Weddell Seal; Whales", "people": "Cziko, Paul", "repository": "USAP-DC", "science_program": null, "title": "Long-Term broadband underwater acoustic recordings from McMurdo Sound, Antarctica (2017-2019)", "url": "https://www.usap-dc.org/view/dataset/601416"}, {"dataset_uid": "601417", "doi": "10.15784/601417", "keywords": "Antarctica; Benthic Ecology; Benthic Invertebrates; Biota; McMurdo Sound; Notothenioid; Notothenioid Fishes; Photo/video; Photo/Video; Rocky Reef Community; Soft-Bottom Community; Timelaps Images", "people": "Cziko, Paul", "repository": "USAP-DC", "science_program": null, "title": "Long-term underwater images from around a single mooring site in McMurdo Sound, Antarctica (2017-2019)", "url": "https://www.usap-dc.org/view/dataset/601417"}], "date_created": "Tue, 15 Dec 2020 00:00:00 GMT", "description": "Notothenioid fishes live in the world\u0027s coldest marine waters surrounding Antarctica and have evolved strategies to avoid freezing. Past studies have shown that most Antarctic notothenioids produce special antifreeze proteins that prevent the growth of ice crystals that enter the body. While these proteins help prevent individuals from being killed by growing ice crystals, it is unclear how these fish avoid the accumulation of these small ice crystals inside their tissues over time. This project will observe how ice crystal accumulation relates to the harshness of the fish\u0027s habitat and the fish\u0027s behavior within different habitats of McMurdo Sound, Antarctica. The researchers will collect fishes and ocean observations at different field sites that cover a range of habitat severity in terms of temperature and iciness. Researchers will install an underwater ocean observatory near McMurdo Station which will include a HD video camera and hydrophone. The observatory will allow continuous monitoring of ocean conditions and fish behavior that will help explain the conditions and behaviors that contribute to the acquisition and accrual of ice inside the body. Acoustic and video data from the observatory will be available to other scientists and to the public. The project will advance understanding of the many challenges life faces in extreme cold environments. This work continues a line of inquiry that has resulted in the discovery of potential medical and food preservation applications. Hundreds of antifreeze protein (AFP) structure-function studies have been conducted in the laboratory, providing a basic physical understanding of the AFP-ice interaction. How AFPs function within fishes and their range of environments, however, is far from clear. This project will provide an understanding of notothenioid\u0027s freezing avoidance mechanisms, and strategies by quantifying the acquisition, accumulation, and loss of internal ice crystals. Specifically, the goal is to determine if and how habitat severity (as defined by iciness, seawater temperature, and prevalence of supercooled water) and fish behavior influence the abundance of ice crystals in their tissues. Four locations in the McMurdo Sound with different levels of habitat severity will be sampled for oceanographic conditions and ice crystal count within fish tissues. Researchers will use a new technique to count the number of splenic ice crystals, expanding on and simplifying previous methods. Environmental data loggers will be deployed for the duration of the project at the four sites to provide context and real-time assessment of environmental conditions. An oceanographic observatory near McMurdo Station will provide year-round, real-time and archival records of oceanographic conditions, in situ video observations of anchor ice growth and ice-organism interactions, hydroacoustic recordings, and serve as proof-of concept for expanding scientific infrastructure in McMurdo Sound related to monitoring of supercooled waters and oceanographic information.", "east": 166.8, "geometry": "POINT(165.135 -77.52)", "instruments": null, "is_usap_dc": true, "keywords": "Benthic Ecology; ANIMALS/VERTEBRATES; USA/NSF; OCEAN TEMPERATURE; USAP-DC; MAMMALS; FIELD INVESTIGATION; Amd/Us; McMurdo Sound; FISH; AMD", "locations": "McMurdo Sound", "north": -77.14, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Cziko, Paul; DeVries, Arthur", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.9, "title": "Habitat Severity and Internal Ice in Antarctic Notothenioid Fishes", "uid": "p0010147", "west": 163.47}, {"awards": "1842021 Campbell, Seth", "bounds_geometry": "POLYGON((-168 -82,-162.3 -82,-156.6 -82,-150.9 -82,-145.2 -82,-139.5 -82,-133.8 -82,-128.1 -82,-122.4 -82,-116.7 -82,-111 -82,-111 -82.5,-111 -83,-111 -83.5,-111 -84,-111 -84.5,-111 -85,-111 -85.5,-111 -86,-111 -86.5,-111 -87,-116.7 -87,-122.4 -87,-128.1 -87,-133.8 -87,-139.5 -87,-145.2 -87,-150.9 -87,-156.6 -87,-162.3 -87,-168 -87,-168 -86.5,-168 -86,-168 -85.5,-168 -85,-168 -84.5,-168 -84,-168 -83.5,-168 -83,-168 -82.5,-168 -82))", "dataset_titles": "2017 GPR Observations of the Whillans and Mercer Ice Streams; Whillans and Mercer Shear Margin Ice Flow simulation in ISSM", "datasets": [{"dataset_uid": "601403", "doi": "10.15784/601403", "keywords": "Antarctica; Crevasses; Glaciology; GPR; GPS; Ice Sheet Flow Model; Ice Shelf Dynamics; Snow/ice; Snow/Ice; Whillans Ice Stream", "people": "Kaluzienski, Lynn", "repository": "USAP-DC", "science_program": null, "title": "2017 GPR Observations of the Whillans and Mercer Ice Streams", "url": "https://www.usap-dc.org/view/dataset/601403"}, {"dataset_uid": "601404", "doi": "10.15784/601404", "keywords": "Antarctica; Glaciology; Ice Sheet Flow Model; Ice Shelf Dynamics; Mercer Ice Stream; Model Data; Snow/ice; Snow/Ice; Whillans Ice Stream", "people": "Kaluzienski, Lynn", "repository": "USAP-DC", "science_program": null, "title": "Whillans and Mercer Shear Margin Ice Flow simulation in ISSM", "url": "https://www.usap-dc.org/view/dataset/601404"}], "date_created": "Mon, 14 Dec 2020 00:00:00 GMT", "description": "The Siple Coast in West Antarctica has undergone significant glacier changes over the last millenium. Several ice streams--rapidly moving streams of ice bordered by slow-moving ice--exist in this region that feeds into the Ross Ice Shelf. A long-term slowdown of Whillans Ice Stream appears to be occurring, and this is affecting the zone between the Whillans and Mercer Ice Streams. However, the consistency of this slowdown and resulting changes to the shear margin between the two ice streams are unknown. The goal of this project is to quantify the observed changes over the past decade and understand the dynamic processes that cause them. A collateral benefit of and driver for this as a RAPID project is to test a method for assessing where crevassing will develop in this zone of steep velocity gradients. Such a method may benefit not only near-term field-project planning in the 2018-19 field season, but also planning for future fieldwork and traverses. The team will use remote sensing feature-tracking techniques to determine transient velocity patterns and shifts in the shear-zone location over the last 10-plus years. This velocity time series will be incorporated into a large-scale ice-sheet model to estimate ice-sheet susceptibility to changing boundary conditions over the next century based on likely regional ice-flux scenarios. This approach is an extension of recent work conducted by the team that shows promise for predicting areas of changing high strain rates indicative of an active glacier shear margin. The ultimate objectives are to characterize the flow field of merging ice streams over time and investigate lateral boundary migration. This will provide a better understanding of shear-margin control on ice-shelf and up-glacier stability. 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": -111.0, "geometry": "POINT(-139.5 -84.5)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "FIELD SURVEYS; Whillans Ice Stream; USAP-DC; Amd/Us; USA/NSF; GLACIER MOTION/ICE SHEET MOTION; MODELS; AMD", "locations": "Whillans Ice Stream", "north": -82.0, "nsf_funding_programs": "Polar Special Initiatives; Antarctic Glaciology", "paleo_time": null, "persons": "Campbell, Seth; Koons, Peter", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e MODELS \u003e MODELS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.0, "title": "RAPID Proposal: Constraining kinematics of the Whillans/Mercer Ice Stream Confluence", "uid": "p0010145", "west": -168.0}, {"awards": "1643798 Emry, Erica; 1643873 Hansen, Samantha", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "GEOSCOPE Network; IU: Global Seismograph Network; Shear Wave Velocity of the Antarctic Upper Mantle from Full Waveform Inversion and Long Period Ambient Seismic Noise; XP (2000-2004): A Broadband Seismic Investigation of Deep Continental Structure Across the East-West Antarctic Boundary ; YT (2007-2023): IPY POLENET-Antarctica: Investigating links between geodynamics and ice sheets; ZJ (2012-2015): Transantarctic Mountains Northern Network ; ZM (2007-2013): A Broadband Seismic Experiment to Image the Lithosphere beneath the Gamburtsev Mountains, East Antarctica", "datasets": [{"dataset_uid": "200168", "doi": "10.18715/GEOSCOPE.G", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "GEOSCOPE Network", "url": "http://geoscope.ipgp.fr/networks/detail/G/"}, {"dataset_uid": "200172", "doi": "10.7914/SN/ZM_2007", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": " ZM (2007-2013): A Broadband Seismic Experiment to Image the Lithosphere beneath the Gamburtsev Mountains, East Antarctica", "url": "http://www.fdsn.org/networks/detail/ZM_2007/"}, {"dataset_uid": "200169", "doi": "10.7914/SN/IU", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IU: Global Seismograph Network", "url": "http://www.fdsn.org/networks/detail/IU/"}, {"dataset_uid": "200171", "doi": "10.7914/SN/YT_2007", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "YT (2007-2023): IPY POLENET-Antarctica: Investigating links between geodynamics and ice sheets", "url": "http://www.fdsn.org/networks/detail/YT_2007/"}, {"dataset_uid": "601909", "doi": "10.15784/601909", "keywords": "Ambient Seismic Noise; Antarctica; Cryosphere; Full-Waveform Inversion; Seismic Tomography; Shear Wave Velocity", "people": "Emry, Erica; Hansen, Samantha", "repository": "USAP-DC", "science_program": null, "title": "Shear Wave Velocity of the Antarctic Upper Mantle from Full Waveform Inversion and Long Period Ambient Seismic Noise", "url": "https://www.usap-dc.org/view/dataset/601909"}, {"dataset_uid": "200170", "doi": "10.7914/SN/XP_2000", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "XP (2000-2004): A Broadband Seismic Investigation of Deep Continental Structure Across the East-West Antarctic Boundary ", "url": "http://www.fdsn.org/networks/detail/XP_2000/"}, {"dataset_uid": "200173", "doi": "10.7914/SN/ZJ_2012", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "ZJ (2012-2015): Transantarctic Mountains Northern Network ", "url": "http://www.fdsn.org/networks/detail/ZJ_2012/"}], "date_created": "Thu, 15 Oct 2020 00:00:00 GMT", "description": "Nontechnical description of proposed research: This project will apply cutting-edge seismic imaging methods to existing seismic data to study the three-dimensional structure of the Earth beneath the ice-covered Antarctic continent. The study will improve understanding of Earth structure and hotspots and geologically recent and ancient rift systems. The results will be useful for models of ice movement and bedrock elevation changes due to variation in ice sheet thickness. The results will also help guide future seismic data collection. The researchers will transfer existing software from the high-performance computers at The University of Rhode Island to the Alabama supercomputer facilities. The project will also broaden public understanding of scientific research in Antarctica by engaging with the students and teachers in Socorro County, New Mexico to discuss career opportunities in science, technology, engineering, and mathematics (STEM), the Earth Sciences, and the importance of computers in scientific research. Project personnel from Alabama will visit Socorro and share research with students at New Mexico Tech and at the Socorro High School. The project will also train undergraduate and graduate students in the expanding field of computational seismology, by applying these approaches to study Antarctic geology. Technical description of proposed research: The project seeks to better resolve the three-dimensional Antarctic mantle structure and viscosity and to identify locations of ancient rifts within the stable East Antarctic lithosphere. To accomplish this, the researchers will utilize full-waveform tomographic inversion techniques that combine long-period ambient noise data with earthquake constraints to more accurately resolve structure than traditional tomographic approaches. The proposed research will be completed using the Alabama supercomputer facilities and the programs and methodology developed at The University of Rhode Island. The new tomographic results will be useful in assessing lithospheric structure beneath Dronning Maud Land as well as the Wilkes and Aurora Subglacial Basins in East Antarctica, where previous rifting episodes and mid-lithospheric discontinuities will be explored. In West Antarctica, the work will elucidate the easternmost extent of the West Antarctic Rift System as well as rifted structure and possible compositional variations within the Weddell Sea. The accuracy of existing Antarctic seismic models will be quantified through model validation approaches. The researchers will highlight regions of Antarctica where tomographic resolution is still lacking and where future deployments would improve resolution.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOGRAPHS", "is_usap_dc": true, "keywords": "SEISMIC SURFACE WAVES; USA/NSF; USAP-DC; SEISMOLOGICAL STATIONS; Amd/Us; AMD; POLNET; TECTONICS; Antarctica", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Emry, Erica; Hansen, Samantha", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e SEISMOLOGICAL STATIONS", "repo": "IRIS", "repositories": "IRIS; USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Imaging Seismic Heterogeneity within the Antarctic Mantle with Full Waveform Ambient Noise Tomography", "uid": "p0010139", "west": -180.0}, {"awards": "1141411 Baker, Ian", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Laboratory Experiments with H2SO4-Doped Ice; The Effects of Soluble Impurities on the Flow and Fabric of Polycrystalline Ice", "datasets": [{"dataset_uid": "601081", "doi": "10.15784/601081", "keywords": null, "people": "Hammonds, Kevin", "repository": "USAP-DC", "science_program": null, "title": "Laboratory Experiments with H2SO4-Doped Ice", "url": "https://www.usap-dc.org/view/dataset/601081"}, {"dataset_uid": "600380", "doi": "10.15784/600380", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Physical Properties; Snow", "people": "Baker, Ian", "repository": "USAP-DC", "science_program": null, "title": "The Effects of Soluble Impurities on the Flow and Fabric of Polycrystalline Ice", "url": "https://www.usap-dc.org/view/dataset/600380"}], "date_created": "Fri, 09 Oct 2020 00:00:00 GMT", "description": "Baker/1141411 This award supports a project to undertake a systematic examination of the effects of soluble impurities, particularly sulfuric acid, on the creep of polycrystalline ice as function of temperature, strain rate and impurity concentration. The working hypothesis is that soluble impurities will increase the flow rate of polycrystalline ice compared to high-purity ice, that this effect will be temperature dependent and that the impurities by affecting the re-crystallization and grain growth will change the fabric of the ice. Both H2SO4-doped and high-purity poly-crystalline ice will be produced by freezing sheets of ice, breaking them up, sieving the ice particles and then sintering them in a mold into fine-grained cylindrical specimens with at least ten grains across their diameter. The resulting microstructures (dislocation structure, grain size and shape, grain boundary character and micro-structural location of the acid) will be characterized using a variety of techniques including: optical microscopy, scanning electron microscopy, including secondary electron imaging, electron backscattered patterns, energy dispersive X-ray spectroscopy, electron channeling contrast imaging, and X-ray topography. The creep of both the H2SO4-doped and the high-purity polycrystalline ice will be undertaken at a range of temperatures and stresses. The ice?s response to the creep deformation (grain boundary sliding, dislocation motion, re-crystallization, grain boundary migration, impurity redistribution) will be studied using a combination of methods. The creep behavior will be modeled and related to the microstructure. Of particular interest is how impurities affect the activation energy for creep. The intellectual merit of the work is that it will lead to a better understanding of glacier ice and will enable glaciologists to model the influence of impurities on the flow and fabric development in polycrystalline ice. The broader impacts of the project include the knowledge that will be gained of the effects of impurities on the flow of ice which will allow paleoclimatologists to better interpret ice core data and will allow scientists developing predictive models to better address the flow of ice sheets under various climate change scenarios. The project will also lead to the education and training of a Ph.D. student, several undergraduates and some high school students. Results from the research will be published in refereed journals. Several undergraduates, typically two per year, will also perform the work. Dartmouth aggressively courts minority students at all degree levels, and we will seek women or minority group undergraduates for this project. The undergraduates will be supported by Dartmouth?s nationally-honored Women In Science Project or by REU funding. The undergraduates? research will integrate closely with the Ph.D. student?s studies. Hanover High School students will also be involved in the project and develop an educational kit to introduce students to the properties of ice. Results from the research will be published in refereed journals and presented at conferences.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; USAP-DC; SNOW/ICE; Amd/Us; LABORATORY; Antarctica; AMD", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Baker, Ian", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "The Effects of Soluble Impurities on the Flow and Fabric of Polycrystalline Ice", "uid": "p0010133", "west": -180.0}, {"awards": "1542962 Anderson, Robert", "bounds_geometry": "POLYGON((-171 -57,-170.8 -57,-170.6 -57,-170.4 -57,-170.2 -57,-170 -57,-169.8 -57,-169.6 -57,-169.4 -57,-169.2 -57,-169 -57,-169 -57.72,-169 -58.44,-169 -59.16,-169 -59.88,-169 -60.6,-169 -61.32,-169 -62.04,-169 -62.76,-169 -63.48,-169 -64.2,-169.2 -64.2,-169.4 -64.2,-169.6 -64.2,-169.8 -64.2,-170 -64.2,-170.2 -64.2,-170.4 -64.2,-170.6 -64.2,-170.8 -64.2,-171 -64.2,-171 -63.48,-171 -62.76,-171 -62.04,-171 -61.32,-171 -60.6,-171 -59.88,-171 -59.16,-171 -58.44,-171 -57.72,-171 -57))", "dataset_titles": "Expedition Data of NBP1702; Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean ; Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean (SNOWBIRDS)", "datasets": [{"dataset_uid": "200126", "doi": "10.7284/907211", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1702", "url": "https://www.rvdata.us/search/cruise/NBP1702"}, {"dataset_uid": "200166", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean ", "url": "https://www.ncdc.noaa.gov/paleo/study/31312"}, {"dataset_uid": "200165", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean (SNOWBIRDS)", "url": "https://www.bco-dmo.org/dataset/813379/data"}], "date_created": "Fri, 25 Sep 2020 00:00:00 GMT", "description": "Scientists established more than 30 years ago that the climate-related variability of carbon dioxide levels in the atmosphere over Earth\u0027s ice-age cycles was regulated by the ocean. Hypotheses to explain how the ocean regulates atmospheric carbon dioxide have long been debated, but they have proven to be difficult to test. Work proposed here will test one leading hypothesis, specifically that the ocean experienced greater density stratification during the ice ages. That is, with greater stratification during the ice ages and slower replacement of deep water by cold dense water formed near the poles, the deep ocean would have held more carbon dioxide, which is produced by biological respiration of the organic carbon that constantly rains to the abyss in the form of dead organisms and organic debris that sink from the sunlit surface ocean. To test this hypothesis, the degree of ocean stratification during the last ice age and the rate of deep-water replacement will be constrained by comparing the radiocarbon ages of organisms that grew in the surface ocean and at the sea floor within a critical region around Antarctica, where most of the replacement of deep waters occurs. Completing this work will contribute toward improved models of future climate change. Climate scientists rely on models to estimate the amount of fossil fuel carbon dioxide that will be absorbed by the ocean in the future. Currently the ocean absorbs about 25% of the carbon dioxide produced by burning fossil fuels. Most of this carbon is absorbed in the Southern Ocean (the region around Antarctica). How this will change in the future is poorly known. Models have difficulty representing physical conditions in the Southern Ocean accurately, thereby adding substantial uncertainty to projections of future ocean uptake of carbon dioxide. Results of the proposed study will provide a benchmark to test the ability of models to simulate ocean processes under climate conditions distinctly different from those that occur today, ultimately leading to improvement of the models and to more reliable projections of future absorption of carbon dioxide by the ocean. The proposed work will add a research component to an existing scientific expedition to the Southern Ocean, in the region between the Ross Sea and New Zealand, that will collect sediment cores at three to five locations down the northern flank of the Pacific-Antarctic Ridge at approximately 170\u00b0W. The goal is to collect sediments at each location deposited since early in the peak of the last ice age. This region is unusual in the Southern Ocean in that sediments deposited during the last ice age contain foraminifera, tiny organisms with calcium carbonate shells, in much greater abundance than in other regions of the Southern Ocean. Foraminifera are widely used as an archive of several geochemical tracers of past ocean conditions. In the proposed work the radiocarbon age of foraminifera that inhabited the surface ocean will be compared with the age of contemporary specimens that grew on the seabed. The difference in age between surface and deep-swelling organisms will be used to discriminate between two proposed mechanisms of deep water renewal during the ice age: formation in coastal polynyas around the edge of Antarctica, much as occurs today, versus formation by open-ocean convection in deep-water regions far from the continent. If the latter mechanism prevails, then it is expected that surface and deep-dwelling foraminifera will exhibit similar radiocarbon ages. In the case of dominance of deep-water formation in coastal polynyas, one expects to find very different radiocarbon ages in the two populations of foraminifera. In the extreme case of greater ocean stratification during the last ice age, one even expects the surface dwellers to appear to be older than contemporary bottom dwellers because the targeted core sites lie directly under the region where the oldest deep waters return to the surface following their long circuitous transit through the deep ocean. The primary objective of the proposed work is to reconstruct the water mass age structure of the Southern Ocean during the last ice age, which, in turn, is a primary factor that controls the amount of carbon dioxide stored in the deep sea. In addition, the presence of foraminifera in the cores to be recovered provides a valuable resource for many other paleoceanographic applications, such as: 1) the application of nitrogen isotopes to constrain the level of nutrient utilization in the Southern Ocean and, thus, the efficiency of the ocean?s biological pump, 2) the application of neodymium isotopes to constrain the transport history of deep water masses, 3) the application of boron isotopes and boron/calcium ratios to constrain the pH and inorganic carbon system parameters of ice-age seawater, and 4) the exploitation of metal/calcium ratios in foraminifera to reconstruct the temperature (Mg/Ca) and nutrient content (Cd/Ca) of deep waters during the last ice age at a location near their source near Antarcitca.", "east": -169.0, "geometry": "POINT(-170 -60.6)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; SEDIMENT CHEMISTRY; South Pacific Ocean; SHIPS", "locations": "South Pacific Ocean", "north": -57.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, Robert; Fleisher, Martin; Pavia, Frank", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "R2R", "repositories": "BCO-DMO; NCEI; R2R", "science_programs": null, "south": -64.2, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean", "uid": "p0010130", "west": -171.0}, {"awards": "1644187 Tulaczyk, Slawek", "bounds_geometry": "POLYGON((161 -76.9,161.75 -76.9,162.5 -76.9,163.25 -76.9,164 -76.9,164.75 -76.9,165.5 -76.9,166.25 -76.9,167 -76.9,167.75 -76.9,168.5 -76.9,168.5 -77.04,168.5 -77.18,168.5 -77.32,168.5 -77.46,168.5 -77.6,168.5 -77.74,168.5 -77.88,168.5 -78.02,168.5 -78.16,168.5 -78.3,167.75 -78.3,167 -78.3,166.25 -78.3,165.5 -78.3,164.75 -78.3,164 -78.3,163.25 -78.3,162.5 -78.3,161.75 -78.3,161 -78.3,161 -78.16,161 -78.02,161 -77.88,161 -77.74,161 -77.6,161 -77.46,161 -77.32,161 -77.18,161 -77.04,161 -76.9))", "dataset_titles": "ANTAEM project airborne EM resistivity data from McMurdo Region", "datasets": [{"dataset_uid": "601373", "doi": "10.15784/601373", "keywords": "Antarctica; Dry Valleys; Hydrology; Ice Shelf; McMurdo; Permafrost", "people": "Tulaczyk, Slawek", "repository": "USAP-DC", "science_program": null, "title": "ANTAEM project airborne EM resistivity data from McMurdo Region", "url": "https://www.usap-dc.org/view/dataset/601373"}], "date_created": "Sun, 13 Sep 2020 00:00:00 GMT", "description": "In Antarctica, millions of years of freezing have led to the development of hundreds of meters of thick permafrost (i.e., frozen ground). Recent research demonstrated that this slow freezing has trapped and concentrated water into local and regional briny aquifers, many times more salty than seawater. Because salt depresses the freezing point of water, these saline brines are able to persist as liquid water at temperatures well below the normal freezing point of freshwater. Such unusual groundwater systems may support microbial life, supply nutrients to coastal ocean and ice-covered lakes, and influence motion of glaciers. These briny aquifers also represent potential terrestrial analogs for deep life habitats on other planets, such as Mars, and provide a testing ground for the search for extraterrestrial water. Whereas much effort has been invested in understanding the physics, chemistry, and biology of surface and near-surface waters in cold polar regions, it has been comparably difficult to investigate deep subsurface aquifers in such settings. Airborne ElectroMagnetics (AEM) subsurface imaging provides an efficient way for mapping salty groundwater. An international collaboration with the University of Aarhus in Denmark will enable knowledge and skill transfer in AEM techniques that will enhance US polar research capabilities and provide US undergraduates and graduate students with unique training experiences. This project will survey over 1000 km2 of ocean and land near McMurdo Station in Antarctica, and will reveal if cold polar deserts hide a subsurface pool of liquid water. This will have significant implications for understanding cold polar glaciers, ice-covered lakes, frozen ground, and polar microbiology as well as for predictions of their response to future change. Improvements in permafrost mapping techniques and understanding of permafrost and of underlying groundwaters will benefit human use of high polar regions in the Antarctic and the Arctic. 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": "1724670 Williams, Trevor", "bounds_geometry": "POLYGON((-70 -60,-65 -60,-60 -60,-55 -60,-50 -60,-45 -60,-40 -60,-35 -60,-30 -60,-25 -60,-20 -60,-20 -62.5,-20 -65,-20 -67.5,-20 -70,-20 -72.5,-20 -75,-20 -77.5,-20 -80,-20 -82.5,-20 -85,-25 -85,-30 -85,-35 -85,-40 -85,-45 -85,-50 -85,-55 -85,-60 -85,-65 -85,-70 -85,-70 -82.5,-70 -80,-70 -77.5,-70 -75,-70 -72.5,-70 -70,-70 -67.5,-70 -65,-70 -62.5,-70 -60))", "dataset_titles": "Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment", "datasets": [{"dataset_uid": "601378", "doi": "10.15784/601378", "keywords": "40Ar/39Ar Thermochronology; Antarctica; Argon; Chemistry:sediment; Chemistry:Sediment; Detrital Minerals; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marine Sediments; Mass Spectrometer; Provenance; R/v Polarstern; Sediment Core Data; Subglacial Till; Till; Weddell Sea", "people": "Williams, Trevor", "repository": "USAP-DC", "science_program": null, "title": "Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment", "url": "https://www.usap-dc.org/view/dataset/601378"}, {"dataset_uid": "601379", "doi": "10.15784/601379", "keywords": "40Ar/39Ar Thermochronology; Antarctica; Argon; Chemistry:sediment; Chemistry:Sediment; Detrital Minerals; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marine Geoscience; Mass Spectrometer; Provenance; R/v Polarstern; Sediment Core Data; Subglacial Till; Till; Weddell Sea", "people": "Williams, Trevor", "repository": "USAP-DC", "science_program": null, "title": "Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment", "url": "https://www.usap-dc.org/view/dataset/601379"}, {"dataset_uid": "601377", "doi": "10.15784/601377", "keywords": "40Ar/39Ar Thermochronology; Antarctica; Argon; Chemistry:sediment; Chemistry:Sediment; Detrital Minerals; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marine Sediments; Mass Spectrometer; Provenance; R/v Polarstern; Sediment Core Data; Subglacial Till; Till; Weddell Sea", "people": "Williams, Trevor", "repository": "USAP-DC", "science_program": null, "title": "Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment", "url": "https://www.usap-dc.org/view/dataset/601377"}], "date_created": "Thu, 10 Sep 2020 00:00:00 GMT", "description": "Abstract for the general public: The margins of the Antarctic ice sheet have advanced and retreated repeatedly over the past few million years. Melting ice from the last retreat, from 19,000 to 9,000 years ago, raised sea levels by 8 meters or more, but the extents of previous retreats are less well known. The main goal of this project is to understand how Antarctic ice retreats: fast or slow, stepped or steady, and which parts of the ice sheet are most prone to retreat. Antarctica loses ice by two main processes: melting of the underside of floating ice shelves and calving of icebergs. Icebergs themselves are ephemeral, but they carry mineral grains and rock fragments that have been scoured from Antarctic bedrock. As the icebergs drift and melt, this \u0027iceberg-rafted debris\u0027 falls to the sea-bed and is steadily buried in marine sediments to form a record of iceberg activity and ice sheet retreat. The investigators will read this record of iceberg-rafted debris to find when and where Antarctic ice destabilized in the past. This information can help to predict how Antarctic ice will behave in a warming climate. The study area is the Weddell Sea embayment, in the Atlantic sector of Antarctica. Principal sources of icebergs are the nearby Antarctic Peninsula and Weddell Sea embayment, where ice streams drain about a quarter of Antarctic ice. The provenance of the iceberg-rafted debris (IRD), and the icebergs that carried it, will be found by matching the geochemical fingerprint (such as characteristic argon isotope ages) of individual mineral grains in the IRD to that of the corresponding source area. In more detail, the project will: 1. Define the geochemical fingerprints of the source areas of the glacially-eroded material using samples from each major ice stream entering the Weddell Sea. Existing data indicates that the hinterland of the Weddell embayment is made up of geochemically distinguishable source areas, making it possible to apply geochemical provenance techniques to determine the origin of Antarctica icebergs. Few samples of onshore tills are available from this area, so this project includes fieldwork to collect till samples to characterize detritus supplied by the Recovery and Foundation ice streams. 2. Document the stratigraphic changes in provenance of iceberg-rafted debris (IRD) and glacially-eroded material in two deep water sediment cores in the NW Weddell Sea. Icebergs calved from ice streams in the embayment are carried by the Weddell Gyre and deposit IRD as they pass over the core sites. The provenance information identifies which groups of ice streams were actively eroding and exporting detritus to the ocean (via iceberg rafting and bottom currents), and the stratigraphy of the cores shows the relative sequence of ice stream activity through time. A further dimension is added by determining the time lag between fine sediment erosion and deposition, using a new method of uranium-series isotope measurements in fine grained material. Technical abstract: The behavior of the Antarctic ice sheets and ice streams is a critical topic for climate change and future sea level rise. The goal of this proposal is to constrain ice sheet response to changing climate in the Weddell Sea during the three most recent glacial terminations, as analogues for potential future warming. The project will also examine possible contributions to Meltwater Pulse 1A, and test the relative stability of the ice streams draining East and West Antarctica. Much of the West Antarctic ice may have melted during the Eemian (130 to 114 Ka), so it may be an analogue for predicting future ice drawdown over the coming centuries. Geochemical provenance fingerprinting of glacially eroded detritus provides a novel way to reconstruct the location and relative timing of glacial retreat during these terminations in the Weddell Sea embayment. The two major objectives of the project are to: 1. Define the provenance source areas by characterizing Ar, U-Pb, and Nd isotopic signatures, and heavy mineral and Fe-Ti oxide compositions of detrital minerals from each major ice stream entering the Weddell Sea, using onshore tills and existing sediment cores from the Ronne and Filchner Ice Shelves. Pilot data demonstrate that detritus originating from the east and west sides of the Weddell Sea embayment can be clearly distinguished, and published data indicates that the hinterland of the embayment is made up of geochemically distinguishable source areas. Few samples of onshore tills are available from this area, so this project includes fieldwork to collect till to characterize detritus supplied by the Recovery and Foundation ice streams. 2. Document the stratigraphic changes in provenance of iceberg-rafted debris (IRD) and glacially-eroded material in two deep water sediment cores in the NW Weddell Sea. Icebergs calved from ice streams in the embayment are carried by the Weddell Gyre and deposit IRD as they pass over the core sites. The provenance information will identify which ice streams were actively eroding and exporting detritus to the ocean (via iceberg rafting and bottom currents). The stratigraphy of the cores will show the relative sequence of ice stream activity through time. A further time dimension is added by determining the time lag between fine sediment erosion and deposition, using U-series comminution ages.", "east": -20.0, "geometry": "POINT(-45 -72.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "TERRIGENOUS SEDIMENTS; Subglacial Till; USAP-DC; ICEBERGS; AMD; USA/NSF; ISOTOPES; AGE DETERMINATIONS; Argon; Provenance; Till; Amd/Us; R/V POLARSTERN; FIELD INVESTIGATION; SEDIMENT CHEMISTRY; Weddell Sea; Antarctica; LABORATORY", "locations": "Weddell Sea; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Williams, Trevor; Hemming, Sidney R.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V POLARSTERN", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance", "uid": "p0010128", "west": -70.0}, {"awards": "1935755 Lamp, Jennifer; 1935907 Balco, Gregory; 1935945 Tremblay, Marissa", "bounds_geometry": "POLYGON((160 -77.25,160.4 -77.25,160.8 -77.25,161.2 -77.25,161.6 -77.25,162 -77.25,162.4 -77.25,162.8 -77.25,163.2 -77.25,163.6 -77.25,164 -77.25,164 -77.325,164 -77.4,164 -77.475,164 -77.55,164 -77.625,164 -77.7,164 -77.775,164 -77.85,164 -77.925,164 -78,163.6 -78,163.2 -78,162.8 -78,162.4 -78,162 -78,161.6 -78,161.2 -78,160.8 -78,160.4 -78,160 -78,160 -77.925,160 -77.85,160 -77.775,160 -77.7,160 -77.625,160 -77.55,160 -77.475,160 -77.4,160 -77.325,160 -77.25))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 25 Aug 2020 00:00:00 GMT", "description": ". ______________________________________________________________________________________________________________ Part I: Nontechnical Description Scientists study the Earth\u0027s past climate in order to understand how the climate will respond to ongoing global change in the future. One of the best analogs for future climate might the period that occurred approximately 3 million years ago, during an interval known as the mid-Pliocene Warm Period. During this period, the concentration of carbon dioxide in the atmosphere was similar to today\u0027s and sea level was 15 or more meters higher, due primarily to warming and consequent ice sheet melting in polar regions. However, the temperatures in polar regions during the mid-Pliocene Warm Period are not well determined, in part because we do not have records like ice cores that extend this far back in time. This project will provide constraints on surface temperatures in Antarctica during the mid-Pliocene Warm Period using a new type of climate substitute, known as cosmogenic noble gas paleothermometry. This project focuses on an area of Antarctica called the McMurdo Dry Valleys. In this area, climate models suggest that temperatures were more than 10 C warmer during the mid-Pliocene than they are today, but indirect geologic observations suggest that temperatures may have been similar to today. The McMurdo Dry Valleys are also a place where rocks have been exposed to Earth surface conditions for several million years, and where this new climate substitute can be readily applied. The team will reconstruct temperatures in the McMurdo Dry Valleys during the mid-Pliocene Warm Period in order to resolve the discrepancy between models and indirect geologic observations and provide much-needed constraints on the sensitivity of Antarctic ice sheets to warming temperatures. The temperature reconstructions generated in this project will have scientific impact in multiple disciplines, including climate science, glaciology, geomorphology, and planetary science. In addition, the project will (1) broaden the participation of underrepresented groups by supporting two early-career female principal investigators, (2) build STEM talent through the education and training of a graduate student, (3) enhance infrastructure for research via publication of a publicly-accessible, open-source code library, and (4) be broadly disseminated via social media, blog posts, publications, and conference presentations. Part II: Technical Description The mid-Pliocene Warm Period (3-3.3 million years ago) is the most recent interval of the geologic past when atmospheric CO2 concentrations exceeded 400 ppm and is widely considered an analog for how Earth\u2019s climate system will respond to current global change. Climate models predict polar amplification - the occurrence of larger changes in temperatures at high latitudes than the global average due to a radiative forcing - both during the mid-Pliocene Warm Period and due to current climate warming. However, the predicted magnitude of polar amplification is highly uncertain in both cases. The magnitude of polar amplification has important implications for the sensitivity of ice sheets to warming and the contribution of ice sheet melting to sea level change. Proxy-based constraints on polar surface air temperatures during the mid-Pliocene Warm Period are sparse to non-existent. In Antarctica, there is only indirect evidence for the magnitude of warming during this time. This project will provide constraints on surface temperatures in the McMurdo Dry Valleys of Antarctica during the mid-Pliocene Warm Period using a newly developed technique called cosmogenic noble gas (CNG) paleothermometry. CNG paleothermometry utilizes the diffusive behavior of cosmogenic 3He in quartz to quantify the temperatures rocks experience while exposed to cosmic-ray particles within a few meters of the Earth\u2019s surface. The very low erosion rates and subzero temperatures characterizing the McMurdo Dry Valleys make this region uniquely suited for the application of CNG paleothermometry for addressing the question: what temperatures characterized the McMurdo Dry Valleys during the mid-Pliocene Warm Period? To address this question, the team will collect bedrock samples at several locations in the McMurdo Dry Valleys where erosion rates are known to be low enough that cosmic ray exposure extends into the mid-Pliocene or earlier. They will pair cosmogenic 3He measurements, which will record the thermal histories of our samples, with measurements of cosmogenic 10Be, 26Al, and 21Ne, which record samples exposure and erosion histories. We will also make in situ measurements of rock and air temperatures at sample sites in order to quantify the effect of radiative heating and develop a statistical relationship between rock and air temperatures, as well as conduct diffusion experiments to quantify the kinetics of 3He diffusion specific to each sample. This suite of observations will be used to model permissible thermal histories and place constraints on temperatures during the mid-Pliocene Warm Period interval of cosmic-ray exposure. 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": 164.0, "geometry": "POINT(162 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; AMD; LABORATORY; USA/NSF; Amd/Us; ISOTOPES; Dry Valleys; AIR TEMPERATURE RECONSTRUCTION; GEOCHEMISTRY; USAP-DC", "locations": "Dry Valleys", "north": -77.25, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Tremblay, Marissa; Granger, Darryl; Balco, Gregory; Lamp, Jennifer", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -78.0, "title": "Collaborative \r\nResearch: Reconstructing Temperatures during the Mid-Pliocene Warm \r\nPeriod in the McMurdo Dry Valleys with Cosmogenic Noble Gases", "uid": "p0010123", "west": 160.0}, {"awards": "1443690 Young, Duncan", "bounds_geometry": "POLYGON((95 -68,100.5 -68,106 -68,111.5 -68,117 -68,122.5 -68,128 -68,133.5 -68,139 -68,144.5 -68,150 -68,150 -70.2,150 -72.4,150 -74.6,150 -76.8,150 -79,150 -81.2,150 -83.4,150 -85.6,150 -87.8,150 -90,144.5 -90,139 -90,133.5 -90,128 -90,122.5 -90,117 -90,111.5 -90,106 -90,100.5 -90,95 -90,95 -87.8,95 -85.6,95 -83.4,95 -81.2,95 -79,95 -76.8,95 -74.6,95 -72.4,95 -70.2,95 -68))", "dataset_titles": "Airborne potential fields data from Titan Dome, Antarctica; ICECAP Basal Interface Specularity Content Profiles: IPY and OIB; ICECAP: Gridded boundary conditions for Little Dome C, Antarctica, and extracted subglacial lake locations; ICECAP: High resolution survey of the Little Dome C region in support of the IPICS Old Ice goal; ICECAP radargrams in support of the international old ice search at Dome C - 2016; Ice-penetrating radar internal stratigraphy over Dome C and the wider East Antarctic Plateau; SPICECAP/ICECAP II Instrument Measurements (LASER, MAGNETICS and POSITIONING); Titan Dome, East Antarctica, Aerogeophysical Survey", "datasets": [{"dataset_uid": "601411", "doi": "10.15784/601411", "keywords": "Antarctica; East Antarctic Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; ICECAP; Ice Penetrating Radar; Internal Reflecting Horizons", "people": "Tozer, Carly; Ritz, Catherine; Blankenship, Donald D.; Schroeder, Dustin; Mulvaney, Robert; Roberts, Jason; Frezzotti, Massimo; Paden, John; Muldoon, Gail R.; Quartini, Enrica; Kempf, Scott D.; Ng, Gregory; Greenbaum, Jamin; Cavitte, Marie G. P; Young, Duncan A.", "repository": "USAP-DC", "science_program": "Dome C Ice Core", "title": "Ice-penetrating radar internal stratigraphy over Dome C and the wider East Antarctic Plateau", "url": "https://www.usap-dc.org/view/dataset/601411"}, {"dataset_uid": "601461", "doi": "10.15784/601461", "keywords": "Antarctica; ICECAP; Titan Dome", "people": "Greenbaum, Jamin; Jingxue, Guo; Blankenship, Donald D.; Young, Duncan A.; Bo, Sun", "repository": "USAP-DC", "science_program": null, "title": "Airborne potential fields data from Titan Dome, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601461"}, {"dataset_uid": "601463", "doi": "10.15784/601463", "keywords": "Antarctica; Epica Dome C; ICECAP; Ice Penetrating Radar; Subglacial Lake", "people": "Young, Duncan A.; Roberts, Jason; Ritz, Catherine; Frezzotti, Massimo; Quartini, Enrica; Cavitte, Marie G. P; Van Ommen, Tas; Blankenship, Donald D.; Steinhage, Daniel; Tozer, Carly; Urbini, Stefano; Corr, Hugh F. J.", "repository": "USAP-DC", "science_program": "Dome C Ice Core", "title": "ICECAP: Gridded boundary conditions for Little Dome C, Antarctica, and extracted subglacial lake locations", "url": "https://www.usap-dc.org/view/dataset/601463"}, {"dataset_uid": "200233", "doi": "http://dx.doi.org/doi:10.26179/5wkf-7361", "keywords": null, "people": null, "repository": "AADC", "science_program": null, "title": "ICECAP radargrams in support of the international old ice search at Dome C - 2016", "url": "https://data.aad.gov.au/metadata/records/AAS_4346_ICECAP_OIA_RADARGRAMS"}, {"dataset_uid": "601371", "doi": "10.15784/601371", "keywords": "Antarctica; East Antarctica; ICECAP; Ice Penetrating Radar; Radar Echo Sounder; Radar Echo Sounding; Subglacial Hydrology", "people": "Young, Duncan A.; Roberts, Jason; Greenbaum, Jamin; Blankenship, Donald D.; Schroeder, Dustin; Siegert, Martin; van Ommen, Tas", "repository": "USAP-DC", "science_program": null, "title": "ICECAP Basal Interface Specularity Content Profiles: IPY and OIB", "url": "https://www.usap-dc.org/view/dataset/601371"}, {"dataset_uid": "601437", "doi": "10.15784/601437", "keywords": "Airborne Laser Altimetry; Airborne Radar; Airplane; Antarctica; Bedrock Elevation; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Thickness; Radar Echo Sounder; Surface Elevation; Titan Dome", "people": "Young, Duncan; Beem, Lucas H.; Young, Duncan A.; Greenbaum, Jamin; Ng, Gregory; Blankenship, Donald D.; Cavitte, Marie G. P; Jingxue, Guo; Bo, Sun", "repository": "USAP-DC", "science_program": null, "title": "Titan Dome, East Antarctica, Aerogeophysical Survey", "url": "https://www.usap-dc.org/view/dataset/601437"}, {"dataset_uid": "601355", "doi": "10.15784/601355", "keywords": "Aerogeophysics; Antarctica; Bed Elevation; Bed Reflectivity; Epica Dome C; Ice Thickness", "people": "Ng, Gregory; Young, Duncan A.; Roberts, Jason; Blankenship, Donald D.; van Ommen, Tas; Richter, Thomas; Greenbaum, Jamin; Cavitte, Marie G. P; Beem, Lucas H.; Quartini, Enrica; Tozer, Carly; Habbal, Feras; Kempf, Scott D.; Ritz, Catherine", "repository": "USAP-DC", "science_program": "Dome C Ice Core", "title": "ICECAP: High resolution survey of the Little Dome C region in support of the IPICS Old Ice goal", "url": "https://www.usap-dc.org/view/dataset/601355"}, {"dataset_uid": "200235", "doi": "10.26179/jydx-yz69", "keywords": null, "people": null, "repository": "AADC", "science_program": null, "title": "SPICECAP/ICECAP II Instrument Measurements (LASER, MAGNETICS and POSITIONING)", "url": "https://data.aad.gov.au/metadata/records/AAS_4346_ICECAP_OIA_Level1B_AEROGEOPHYSICS"}], "date_created": "Tue, 07 Jul 2020 00:00:00 GMT", "description": "Non-technical description: East Antarctica holds a vast, ancient ice sheet. The bedrock hidden beneath this ice sheet may provide clues to how today\u0027s continents formed, while the ice itself contains records of Earth\u0027s atmosphere from distant eras. New drilling technologies are now available to allow for direct sampling of these materials from more than two kilometers below the ice surface. However, getting this material will require knowing where to look. The Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP) project will use internationally collected airborne survey data to search East Antarctica near the South Pole for key locations that will provide insight into Antarctica\u0027s geology and for locating the oldest intact ice on Earth. Ultimately, scientists are interested in obtaining samples of the oldest ice to address fundamental questions about the causes of changes in the timing of ice-age conditions from 40,000 to 100,000 year cycles. SPICECAP data analysis will provide site survey data for future drilling and will increase the overall understanding of Antarctica\u0027s hidden ice and geologic records. The project involves international collaboration and leveraging of internationally collected data. The SPICECAP project will train new interdisciplinary scientists at the undergraduate, graduate, and postdoctoral levels. Technical description: This study focuses on processing and interpretation of internationally collected aerogeophysical data from the Southern Plateau of the East Antarctic Ice Sheet. The data include ice penetrating radar data, laser altimetry, gravity and magnetics.\u00a0 The project will provide information on geological trends under the ice, the topography and character of the ice/rock interface, and the stratigraphy of the ice. The project will also provide baseline site characterization for future drilling. Future drilling sites and deep ice cores for old ice require that the base of the ice sheet be frozen to the bed (i.e. no free water at the interface between rock and ice) and the assessment will map the extent of frozen vs. thawed areas. Specifically, three main outcomes are anticipated for this project. First, the study will provide an assessment of the viability of Titan Dome, a subglacial highland region located near South Pole, as a potential old ice drilling prospect. The assessment will include determining the\u00a0hydraulic context of the bed by processing and interpreting the radar data,\u00a0ice sheet mass balance through time by mapping englacial reflectors in the ice and connecting them to ice stratigraphy in the recent South Pole,\u00a0and ice sheet geometry using laser altimetry. Second, the study will provide an assessment of the geological context of the Titan Dome region with respect to understanding regional geologic boundaries and the potential for bedrock sampling. For these two goals, we will use data opportunistically collected by China, and the recent PolarGAP dataset. Third, the study will provide an assessment of the risk posture for RAID site targeting in the Titan Dome region, and the Dome C region. This will use a high-resolution dataset the team collected previously at Dome C, an area similar to the coarser resolution data collected at Titan Dome, and will enable an understanding of what is missed by the wide lines spacing at Titan Dome. Specifically, we will model subglacial hydrology with and without the high resolution data, and statistically examine the detection of subglacial mountains (which could preserve old ice) and subglacial lakes (which could destroy old ice), as a function of line spacing.", "east": 150.0, "geometry": "POINT(122.5 -79)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e LIDAR/LASER ALTIMETERS \u003e LIDAR ALTIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e MAGNETIC FIELD/ELECTRIC FIELD INSTRUMENTS \u003e NUCLEAR PRECESSION MAGNETOMETER", "is_usap_dc": true, "keywords": "BT-67; MAGNETIC ANOMALIES; Epica Dome C; GRAVITY ANOMALIES; GLACIER ELEVATION/ICE SHEET ELEVATION; GLACIER THICKNESS/ICE SHEET THICKNESS", "locations": "Epica Dome C", "north": -68.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Young, Duncan A.; Blankenship, Donald D.; Roberts, Jason; Bo, Sun", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e BT-67", "repo": "USAP-DC", "repositories": "AADC; USAP-DC", "science_programs": "Dome C Ice Core", "south": -90.0, "title": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP)", "uid": "p0010115", "west": 95.0}, {"awards": "1235094 Thurnherr, Andreas", "bounds_geometry": "POLYGON((-19 -19,-18.2 -19,-17.4 -19,-16.6 -19,-15.8 -19,-15 -19,-14.2 -19,-13.4 -19,-12.6 -19,-11.8 -19,-11 -19,-11 -19.4,-11 -19.8,-11 -20.2,-11 -20.6,-11 -21,-11 -21.4,-11 -21.8,-11 -22.2,-11 -22.6,-11 -23,-11.8 -23,-12.6 -23,-13.4 -23,-14.2 -23,-15 -23,-15.8 -23,-16.6 -23,-17.4 -23,-18.2 -23,-19 -23,-19 -22.6,-19 -22.2,-19 -21.8,-19 -21.4,-19 -21,-19 -20.6,-19 -20.2,-19 -19.8,-19 -19.4,-19 -19))", "dataset_titles": "Expedition Data; NBP1406 Expedition data; NBP1508 Expedition data; Processed Current Measurement Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508; Processed Current Measurement, Pressure and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508 (2015); Processed Current Measurement, Pressure, Salinity and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "datasets": [{"dataset_uid": "601353", "doi": null, "keywords": "CTD; CTD Data; Current Measurements; Current Meter; Mid-Ocean Ridge; Mooring; NBP1508; Oceans; Physical Oceanography; Pressure; R/v Nathaniel B. Palmer; Salinity; South Atlantic Ocean; Temperature", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement, Pressure and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508 (2015)", "url": "https://www.usap-dc.org/view/dataset/601353"}, {"dataset_uid": "200153", "doi": "10.7284/903009", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1406 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1406"}, {"dataset_uid": "601352", "doi": null, "keywords": "CTD; Mid-Ocean Ridge; Mooring; NBP1508; Oceans; Physical Oceanography; Pressure; R/v Nathaniel B. Palmer; Salinity; South Atlantic Ocean; Temperature", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement, Pressure, Salinity and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "url": "https://www.usap-dc.org/view/dataset/601352"}, {"dataset_uid": "601354", "doi": "10.15784/601354", "keywords": "Current Measurements; LADCP; Mid-Ocean Ridge; NBP1508; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; South Atlantic Ocean", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "url": "https://www.usap-dc.org/view/dataset/601354"}, {"dataset_uid": "001408", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1406"}, {"dataset_uid": "200154", "doi": "10.7284/906708", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1508 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1508"}], "date_created": "Thu, 02 Jul 2020 00:00:00 GMT", "description": "Overview: In order to close the global overturning circulation, high-density deep- and bottom waters produced at high latitudes must be made less dense and upwell to shallower depths. Available observations from the subtropical South Atlantic indicate that the bulk of the mixing in the deep ocean there takes place over the topographically rough Mid-Atlantic Ridge, in particular in the quasi-regularly spaced \"fracture zone canyons\" corrugating the ridge flanks. There, dense water is advected toward the ridge crest (i.e. upwelled) by persistent along-valley currents that flow down the unidirectional density gradients, which are maintained by strong turbulence (diapycnal mixing). Most of the data on which these inferences are based were collected during the Brazil Basin Tracer Release Experiment (BBTRE) along a single ridge-flank canyon in the western South Atlantic near 22S where previous analyses have shown that both tidal mixing and overflow processes are important. Therefore, it is likely that both processes must be considered in order to understand and parameterize the effects of turbulence and mixing in the canyons corrugating the flanks of all slow-spreading ridges, which make up large fractions of the sea floor, in particular in the Atlantic, Indian and Southern Oceans. The primary aim of this follow-on project is to improve our understanding of the dynamics over the corrugated flanks of slow-spreading mid-ocean ridges. Due to the coarse sampling resolution and choice of station locations it is not possible to answer important questions, such as the relative importance of tidal and sill mixing, from the BBTRE data. Therefore, high-resolution surveys of hydrography, three-dimensional flow, turbulence and mixing will be carried out in two neighboring canyons and over the intervening topographic spur in the BBTRE region to determine the relative contributions of tidal and sill-related mixing. Furthermore, profiling moorings deployed on two nearby sill regions will be used to derive time series of spatially integrated mixing related buoyancy fluxes and to investigate the strong but unexplained sub-inertial variability of the along-canyon flow recorded previously. Additionally, three small moorings will be deployed in saddles between the two canyons to investigate inter-canyon exchange. The data analysis will include available data from previous experiments, including a set of tracer profiles that has not been analyzed before. Intellectual Merit: The corrugated flanks of slow-spreading ridges cover large areas of the sea floor of several major ocean basins. Therefore, understanding the dynamics in the ~100 km of ridge-flank canyons and its effects on the buoyancy and upwelling budget of the abyssal ocean is of global significance. In addition to determining the relative importance of tidal mixing and cross-sill flows in two canyons, the temporal variability of turbulence and mixing from tidal to yearly time scales will be investigated to gain insights into the forcing of the along-canyon flows, the exchange between neighboring canyons, and the eventual fate of the canyon waters. Broader Impacts: It is anticipated that insights gained during this project will improve our understanding of abyssal mixing in many different regions with similar bottom topography and provide the basis for better parameterizations of the effects of turbulence and mixing in large-scale circulation and climate models that cannot resolve these small-scale processes. As part of the project, a graduate student and a post-doctoral researcher will be trained in all aspects of observational physical oceanography, from data acquisition to interpretation.", "east": -11.0, "geometry": "POINT(-15 -21)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "OCEAN CURRENTS; South Atlantic Ocean; R/V NBP; WATER MASSES", "locations": "South Atlantic Ocean", "north": -19.0, "nsf_funding_programs": null, "paleo_time": null, "persons": "Thurnherr, Andreas", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -23.0, "title": "Collaborative Research: Flow, Turbulence and Mixing in Mid-Ocean Ridge Fracture Zone Canyons", "uid": "p0010114", "west": -19.0}, {"awards": "1341658 Mukhopadhyay, Sujoy", "bounds_geometry": "POLYGON((-116.45 -84.786,-116.443 -84.786,-116.436 -84.786,-116.429 -84.786,-116.422 -84.786,-116.415 -84.786,-116.408 -84.786,-116.401 -84.786,-116.394 -84.786,-116.387 -84.786,-116.38 -84.786,-116.38 -84.7864,-116.38 -84.7868,-116.38 -84.7872,-116.38 -84.7876,-116.38 -84.788,-116.38 -84.7884,-116.38 -84.7888,-116.38 -84.7892,-116.38 -84.7896,-116.38 -84.79,-116.387 -84.79,-116.394 -84.79,-116.401 -84.79,-116.408 -84.79,-116.415 -84.79,-116.422 -84.79,-116.429 -84.79,-116.436 -84.79,-116.443 -84.79,-116.45 -84.79,-116.45 -84.7896,-116.45 -84.7892,-116.45 -84.7888,-116.45 -84.7884,-116.45 -84.788,-116.45 -84.7876,-116.45 -84.7872,-116.45 -84.7868,-116.45 -84.7864,-116.45 -84.786))", "dataset_titles": "Ohio Range Subglacial rock core cosmogenic nuclide data", "datasets": [{"dataset_uid": "601351", "doi": "10.15784/601351", "keywords": "Aluminum-26; Antarctica; Beryllium-10; Cosmogenic Dating; Cosmogenic Radionuclides; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Fluctuations; Ohio Range; Rocks", "people": "Mukhopadhyay, Sujoy", "repository": "USAP-DC", "science_program": null, "title": "Ohio Range Subglacial rock core cosmogenic nuclide data", "url": "https://www.usap-dc.org/view/dataset/601351"}], "date_created": "Sun, 28 Jun 2020 00:00:00 GMT", "description": "Modeling fluctuations in the extent of the West Antarctic Ice Sheet (WAIS) over time is a principal goal of the glaciological community. These models will provide a critical basis for predictions of future sea level change, and therefore this work great societal relevance. The mid-Pliocene time interval is of particular interest, as it is the most recent period in which global temperatures were warmer and atmospheric CO2 concentrations may have been higher than current levels. However, observational constraints on fluctuations in the WAIS older than the last glacial maximum are rare. The investigators propose to collect geochemical data from the Ohio Range and Scott Glacier to quantify past variability in the height of the WAIS. Limited available cosmogenic nuclide data are broadly consistent with a model indicating that Pliocene WAIS elevations and volumes were smaller than at present, and that WAIS collapse was common. The PIs will use geologic observations and cosmogenic nuclide concentrations from bedrock samples at multiple locations and at multiple elevations, including sub-ice samples, to constrain WAIS ice volume changes in a \"dipstick\" like fashion. Data obtained from the proposed research will provide targets for data-ice sheet model comparisons to accurately characterize Plio-Pleistocene and future WAIS behavior. As part of this project, the investigators will work with the Natural History Museum and the Earth \u0026 Planetary Science department at Harvard to develop an exhibit that will become part of the Museum\u0027s recently opened Earth and Planetary Science Gallery. The project involves mentoring of a female graduate student as well as an undergraduate student.", "east": -116.38, "geometry": "POINT(-116.415 -84.788)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ROCK CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e AMS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Ice Sheet Fluctuations; ALUMINUM-26 ANALYSIS; BERYLLIUM-10 ANALYSIS; Cosmogenic Radionuclides; USAP-DC; FIELD INVESTIGATION; AMD; Ohio Range; GLACIER THICKNESS/ICE SHEET THICKNESS; ICE SHEETS; LABORATORY", "locations": "Ohio Range", "north": -84.786, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Mukhopadhyay, Sujoy", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.79, "title": "Constraining Plio-Pleistocene West Antarctic Ice Sheet Behavior from the Ohio Range and Scott Glacier", "uid": "p0010113", "west": -116.45}, {"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": "1744550 Amsler, Charles; 1744570 Galloway, Aaron; 1744602 Iken, Katrin; 1744584 Klein, Andrew", "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": "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": "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": "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": "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": "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": "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": "601653", "doi": "10.15784/601653", "keywords": "Antarctica; Antarctic Peninsula; Biota; Carbon; Carbon Isotopes; LMG1904; Nitrogen Isotopes; Oceans", "people": "Iken, Katrin", "repository": "USAP-DC", "science_program": null, "title": "Carbon and nitrogen isotope data along a gradient at the Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601653"}, {"dataset_uid": "601610", "doi": "10.15784/601610", "keywords": "Antarctica; Antarctic Peninsula; Benthic Communities; Biota; Macroalgae; Macroinvertebrates; Oceans; Video Transects", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Underwater transect videos used for community analyses", "url": "https://www.usap-dc.org/view/dataset/601610"}, {"dataset_uid": "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": "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": "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": "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": "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": "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": "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": "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"}, {"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": "601651", "doi": "10.15784/601651", "keywords": "Antarctica; Antarctic Peninsula; Biota; GIS; GIS Data; LMG1904; R/v Laurence M. Gould; Solar Radiation", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Modelled Solar Irradiance for Western Antarctic Pennisula", "url": "https://www.usap-dc.org/view/dataset/601651"}, {"dataset_uid": "601649", "doi": "10.15784/601649", "keywords": "Antarctica; Antarctic Peninsula; LMG1904; National Ice Center Charts; Sea Ice Concentration", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Five year mean annual and summer sea ice concentration grids for the Western Antarctic Peninsula from AMSR2, National Ice Center Charts and the Sea Ice Index ", "url": "https://www.usap-dc.org/view/dataset/601649"}], "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": "1644020 Sims, Kenneth W.; 1644027 Wallace, Paul; 1644013 Gaetani, Glenn", "bounds_geometry": "POLYGON((164.1 -77.1,164.65 -77.1,165.2 -77.1,165.75 -77.1,166.3 -77.1,166.85 -77.1,167.4 -77.1,167.95 -77.1,168.5 -77.1,169.05 -77.1,169.6 -77.1,169.6 -77.235,169.6 -77.37,169.6 -77.505,169.6 -77.64,169.6 -77.775,169.6 -77.91,169.6 -78.045,169.6 -78.18,169.6 -78.315,169.6 -78.45,169.05 -78.45,168.5 -78.45,167.95 -78.45,167.4 -78.45,166.85 -78.45,166.3 -78.45,165.75 -78.45,165.2 -78.45,164.65 -78.45,164.1 -78.45,164.1 -78.315,164.1 -78.18,164.1 -78.045,164.1 -77.91,164.1 -77.775,164.1 -77.64,164.1 -77.505,164.1 -77.37,164.1 -77.235,164.1 -77.1))", "dataset_titles": "G170 Electron Microprobe Analyses of Melt Inclusions and Host Olivines; G170 Raman Spectroscopy \u0026 Tomography Volumes of Melt Inclusions and Vapor Bubbles; G170 Sample Locations Ross Island \u0026 Discovery Province; G170 Secondary Ion Mass Spectrometry Analses of Melt Inclusion Volatiles; G170 Secondary Ion Mass Spectrometry Analyses of Melt Inclusion Hydrogen Isotopes; Location and Description of Tephra Samples from the Erebus and Discovery Sub-provinces", "datasets": [{"dataset_uid": "601505", "doi": "10.15784/601505", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Electron Microprobe Analyses; Olivine; Petrography; Ross Island", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Electron Microprobe Analyses of Melt Inclusions and Host Olivines", "url": "https://www.usap-dc.org/view/dataset/601505"}, {"dataset_uid": "601506", "doi": "10.15784/601506", "keywords": "Antarctica; Ion Mass Spectrometry; Ross Island; Volatiles", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Secondary Ion Mass Spectrometry Analses of Melt Inclusion Volatiles", "url": "https://www.usap-dc.org/view/dataset/601506"}, {"dataset_uid": "601507", "doi": "10.15784/601507", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Hydrogen; Ion Mass Spectrometry; Ross Island", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Secondary Ion Mass Spectrometry Analyses of Melt Inclusion Hydrogen Isotopes", "url": "https://www.usap-dc.org/view/dataset/601507"}, {"dataset_uid": "601250", "doi": "10.15784/601250", "keywords": "Antarctica; Hut Point Peninsula; Mt. Bird; Mt. Morning; Mt. Terror; Ross Island; Turks Head; Turtle Rock", "people": "Gaetani, Glenn; Pamukcu, Ayla", "repository": "USAP-DC", "science_program": null, "title": "Location and Description of Tephra Samples from the Erebus and Discovery Sub-provinces", "url": "https://www.usap-dc.org/view/dataset/601250"}, {"dataset_uid": "601508", "doi": "10.15784/601508", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Melt Inclusions; Raman Spectroscopy; Ross Island; Vapor Bubbles; Volcanic", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Raman Spectroscopy \u0026 Tomography Volumes of Melt Inclusions and Vapor Bubbles", "url": "https://www.usap-dc.org/view/dataset/601508"}, {"dataset_uid": "601504", "doi": "10.15784/601504", "keywords": "Antarctica; Ross Island; Sample/collection Description; Sample/Collection Description; Sample Location", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Sample Locations Ross Island \u0026 Discovery Province", "url": "https://www.usap-dc.org/view/dataset/601504"}], "date_created": "Sat, 08 Feb 2020 00:00:00 GMT", "description": "Nontechnical project description Globally, 500 million people live near and are threatened by active volcanoes. An important step in mitigating volcanic hazards is understanding the variables that influence the explosivity of eruptions. The rate at which a magma ascends from the reservoir within the Earth to the surface is one such variable. However, magma ascent rates are particularly difficult to determine because of the lack of reliable methods for investigating the process. This research applies a new approach to study magma storage depths and ascent rates at the Erebus volcanic province of Antarctica, one of Earth\u0027s largest alkaline volcanic centers. Small pockets of magma that become trapped within growing olivine crystals are called melt inclusions. The concentrations of water and carbon dioxide in these melt inclusions preserve information on the depth of magma reservoirs. Changes to the concentration and isotopic composition of water in the inclusions provide information on how long it took for the host magma to rise to the surface. In combination, these data from samples of olivine-rich volcanic deposits in the Erebus volcanic province will be used to determine the depths at which magmas are stored and their ascent rates. The project results will provide a framework for understanding volcanic hazards associated with alkaline volcanism worldwide. In addition, this project facilitates collaboration among three institutions, and provides an important educational opportunity for a postdoctoral researcher. Technical project description The depths at which magmas are stored, their pre-eruptive volatile contents, and the rates at which they ascend to the Earth\u0027s surface are important controls on the dynamics of volcanic eruptions. Basaltic magmas are likely to be vapor undersaturated as they begin their ascent from the mantle through the crust, but volatile solubility drops with decreasing pressure. Once vapor saturation is achieved and the magma begins to degas, its pre-eruptive volatile content is determined largely by the depth at which it resides within the crust. Magma stored in deeper reservoirs tend to experience less pre-eruptive degassing and to be richer in volatiles than magma shallower reservoirs. Eruptive style is influenced by the rate at which a magma ascends from the reservoir to the surface through its effect on the efficiency of vapor bubble nucleation, growth, and coalescence. The proposed work will advance our understanding of pre-eruptive storage conditions and syn-eruptive ascent rates through a combined field and analytical research program. Volatile measurements from olivine-hosted melt inclusions will be used to systematically investigate magma storage depths and ascent rates associated with alkaline volcanism in the Erebus volcanic province. A central goal of the project is to provide a spatial and temporal framework for interpreting results from studies of present-day volcanic processes at Mt Erebus volcano. The Erebus volcanic province of Antarctica is especially well suited to this type of investigation because: (1) there are many exposed mafic scoria cones, fissure vents, and hyaloclastites (exposed in sea cliffs) that produced rapidly quenched, olivine-rich tephra; (2) existing volatile data for Ross Island MIs show that magma storage was relatively deep compared to many mafic volcanic systems; (3) some of the eruptive centers ejected mantle xenoliths, allowing for comparison of ascent rates for xenolith-bearing and xenolith-free eruptions, and comparison of ascent rates for those bearing xenoliths with times estimated from settling velocities; and (4) the cold, dry conditions in Antarctica result in excellent tephra preservation compared to tropical and even many temperate localities. The project provides new tools for assessing volcanic hazards, facilitates collaboration involving researchers from three different institutions (WHOI, U Wyoming, and U Oregon), supports the researchers\u0027 involvement in teaching, advising, and outreach, and provides an educational opportunity for a promising young postdoctoral researcher. Understanding the interrelationships among magma volatile contents, reservoir depths, and ascent rates is vital for assessing volcanic hazards associated with alkaline volcanism across the globe.", "east": 169.6, "geometry": "POINT(166.85 -77.775)", "instruments": null, "is_usap_dc": true, "keywords": "Tephra; Turtle Rock; USA/NSF; Amd/Us; LABORATORY; AMD; Ross Island; Turks Head; Hut Point Peninsula; LAVA SPEED/FLOW; USAP-DC; Mt. Morning; Mt. Terror; ROCKS/MINERALS/CRYSTALS; Mt. Bird; FIELD INVESTIGATION", "locations": "Ross Island; Mt. Morning; Mt. Bird; Mt. Terror; Hut Point Peninsula; Turtle Rock; Turks Head", "north": -77.1, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Gaetani, Glenn; Le Roux, Veronique; Sims, Kenneth; Wallace, Paul", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.45, "title": "Collaborative Research: Determining Magma Storage Depths and Ascent Rates for the Erebus Volcanic Province, Antarctica Using Diffusive Water Loss from Olivine-hosted Melt Inclusion", "uid": "p0010081", "west": 164.1}, {"awards": "1643864 Talghader, Joseph", "bounds_geometry": "POINT(-112.085 -79.467)", "dataset_titles": " Automated c-axis stage images of WDC-06A 420 vertical thin section from WAIS Divide, Antarctica", "datasets": [{"dataset_uid": "601254", "doi": "10.15784/601254", "keywords": "Antarctica; C-axis; Ice; Microscopy; Thin Sections", "people": "Talghader, Joseph; Mah, Merlin", "repository": "USAP-DC", "science_program": null, "title": " Automated c-axis stage images of WDC-06A 420 vertical thin section from WAIS Divide, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601254"}], "date_created": "Sat, 08 Feb 2020 00:00:00 GMT", "description": "Part I: Nontechnical One of the most interesting historical records that science can provide is contained in the ice of Antarctica. Layer by layer over hundreds of thousands of years, snow has precipitated on the ice sheet, become compacted, and turned into additional ice. Any dust or other impurities in the air or snow have been precipitated as well and thus each snowfall leaves a snapshot record of the atmosphere that existed at or near the time of deposition. A detailed chronology of volcanic eruptions can be obtained from the ice layers where ash and other volcanic products were deposited. Normally, the analysis of volcanic layers requires the physical extraction of a core from the ice sheet; however, chronologies from cores have discontinuities and are difficult, time-consuming, and expensive to obtain. Borehole logging is a measurement method where one lowers instrumentation into a drilled hole in the ice, whether or not core has been retrieved. To date, this technology has only been used to measure optical systems to identify volcanic ash and other impurity layers. In this program, a profiling technology will be developed that measures the conductivity of the ice. A radio-frequency emitter lowered into the borehole will create a return signal that changes depending on the local conductivity, which depends on the concentration of dissolved ions. For example, dissolved sulfates are a critical marker of volcanic activity that may not be coincident with deposited ash. Other dissolved ions, such as chloride, can be indicative of other processes. It is expected that this borehole profiling instrument will be able to help rapidly identify volcanic eruptions that had potentially global impact, distinguish between different dissolved ions via their frequency dependencies, and assist in establishing chronologies between different ice cores and boreholes. Part II: Technical Description Borehole logging of the polar ice sheets is one of the most important methods that earth scientists have to identify and date volcanic eruptions. However, current technology only indicates the presence and depth of ash from an eruption. In order to extract more detailed information, one must obtain an ice core, and laboriously measure each section in the laboratory using electrical conductivity or dielectric measurements to determine the presence or absence of dissolved sulfate and its location relative to the corresponding ash, if any. This program will investigate and demonstrate a borehole logging-compatible radio-frequency dielectric sensor to detect and measure spikes in dissolved major ions chemistry in ice, particularly in intervals corresponding to volcanically produced sulfates. The sulfate layers are one of the primary signatures of volcanic products. However, other ions, such as chlorides, calcium, and others are also commonly seen in ice, and the dielectric logging technology of this program would also measure these. It is expected that certain sets of ions will be distinguishable by their frequency dependencies. This technique could guide other investigators, who are using conventional core scanning and sampling methods, to regions of special interest in corresponding core. We plan to construct a ring-based electrode system and test this system on a variety of artificial ice boreholes and ice cores. This unit will not include a pressure vessel or other borehole logger packing. We will test different means of applying electrical signals including short pulses and periodic waves. We will further utilize differential measurements with low noise circuits and filters to achieve maximum sensitivity. We will correlate the signals extracted with known molarities of sulfates and other ions and measured ECM records. We will perform scaled-down experiments using real ice cores stored in Bay?s lab at UC Berkeley. This will permit testing of different designs in ice with natural impurities and polycrystalline structure. This small collection includes cores from a variety of locations in Antarctica and Greenland, and a variety of ages as old as a million years.", "east": -112.085, "geometry": "POINT(-112.085 -79.467)", "instruments": null, "is_usap_dc": true, "keywords": "WAIS Divide; USAP-DC; Amd/Us; GLACIERS/ICE SHEETS; USA/NSF; FIELD INVESTIGATION; Ice Core; AMD", "locations": "WAIS Divide", "north": -79.467, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Instrumentation and Facilities", "paleo_time": null, "persons": "Talghader, Joseph", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.467, "title": "Collaborative Research: Borehole Logging to Classify Volcanic Signatures in Antarctic Ice", "uid": "p0010080", "west": -112.085}, {"awards": "1443371 Fountain, Andrew", "bounds_geometry": "POLYGON((160.2 -77.1,160.57 -77.1,160.94 -77.1,161.31 -77.1,161.68 -77.1,162.05 -77.1,162.42 -77.1,162.79 -77.1,163.16 -77.1,163.53 -77.1,163.9 -77.1,163.9 -77.196,163.9 -77.292,163.9 -77.388,163.9 -77.484,163.9 -77.58,163.9 -77.676,163.9 -77.772,163.9 -77.868,163.9 -77.964,163.9 -78.06,163.53 -78.06,163.16 -78.06,162.79 -78.06,162.42 -78.06,162.05 -78.06,161.68 -78.06,161.31 -78.06,160.94 -78.06,160.57 -78.06,160.2 -78.06,160.2 -77.964,160.2 -77.868,160.2 -77.772,160.2 -77.676,160.2 -77.58,160.2 -77.484,160.2 -77.388,160.2 -77.292,160.2 -77.196,160.2 -77.1))", "dataset_titles": "McMurdo Dry Valleys LTER: A digital archive of human activity in the McMurdo Dry Valleys, Antarctica from 1902 to present", "datasets": [{"dataset_uid": "200086", "doi": "10.6073/pasta/0725cbd31f2af4bca2c6ad145e38dd3a", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "McMurdo Dry Valleys LTER: A digital archive of human activity in the McMurdo Dry Valleys, Antarctica from 1902 to present", "url": "https://doi.org/10.6073/pasta/0725cbd31f2af4bca2c6ad145e38dd3a"}], "date_created": "Thu, 21 Nov 2019 00:00:00 GMT", "description": "Beginning with the discovery of a \"curious valley\" in 1903 by Captain Scott, the McMurdo Dry Valleys (MDV) in Antarctica have been impacted by humans, although there were only three brief visits prior to 1950. Since the late 1950\u0027s, human activity in the MDV has become commonplace in summer, putting pressure on the region\u0027s fragile ecosystems through camp construction and inhabitation, cross-valley transport on foot and via vehicles, and scientific research that involves sampling and deployment of instruments. Historical photographs, put alongside information from written documentation, offer an invaluable record of the changing patterns of human activity in the MDV. Photographic images often show the physical extent of field camps and research sites, the activities that were taking place, and the environmental protection measures that were being followed. Historical photographs of the MDV, however, are scattered in different places around the world, often in private collections, and there is a real danger that many of these photos may be lost, along with the information they contain. This project will collect and digitize historical photographs of sites of human activity in the MDV from archives and private collections in the United States, New Zealand, and organize them both chronologically and spatially in a GIS database. Sites of past human activities will be re-photographed to provide comparisons with the present, and re-photography will assist in providing spatial data for historical photographs without obvious location information. The results of this analysis will support effective environmental management into the future. The digital photo archive will be openly available through the McMurdo Dry Valleys Long Term Ecological Research (MCM LTER) website (www.mcmlter.org), where it can be used by scientists, environmental managers, and others interested in the region. The central question of this project can be reformulated as a hypothesis: Despite an overall increase in human activities in the MDV, the spatial range of these activities has become more confined over time as a result of an increased awareness of ecosystem fragility and efforts to manage the region. To address this hypothesis, the project will define the spatial distribution and temporal frequency of human activity in the MDV. Photographs and reports will be collected from archives with polar collections such as the National Archives of New Zealand in Wellington and Christchurch and the Byrd Polar Research Center in Ohio. Private photograph collections will be accessed through personal connections, social media, advertisements in periodicals such as The Polar Times, and other means. Re-photography in the field will follow established techniques and will create benchmarks for future research projects. The spatial data will be stored in an ArcGIS database for analysis and quantification of the human footprint over time in the MDV. The improved understanding of changing patterns of human activity in the MDV provided by this historical photo archive will provide three major contributions: 1) a fundamentally important historic accounting of human activity to support current environmental management of the MDV; 2) defining the location and type of human activity will be of immediate benefit in two important ways: a) places to avoid for scientists interested in sampling pristine landscapes, and, b) targets of opportunity for scientists investigating the long-term environmental legacy of human activity; and 3) this research will make an innovative contribution to knowledge of the environmental history of the MDV.", "east": 163.9, "geometry": "POINT(162.05 -77.58)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "CONTAMINANT LEVELS/SPILLS; Antarctica; NOT APPLICABLE; USAP-DC", "locations": "Antarctica", "north": -77.1, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Fountain, Andrew; Howkins, Adrian", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "EDI", "repositories": "EDI", "science_programs": null, "south": -78.06, "title": "Collaborative Research: Assessing Changing Patterns of Human Activity in the McMurdo Dry Valleys using Digital Photo Archives", "uid": "p0010066", "west": 160.2}, {"awards": "1443105 Steig, Eric", "bounds_geometry": "POINT(0 -90)", "dataset_titles": "Continuous-flow measurements of the complete water isotope ratios (D/H, 17O/16O, 18O/16) from the South Pole ice core; South Pole high resolution ice core water stable isotope record for dD, d18O; South Pole Ice Core Holocene Major Ion Dataset; South Pole Ice Core Sea Salt and Major Ions; SP19 Gas Chronology; Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "datasets": [{"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}, {"dataset_uid": "601429", "doi": "10.15784/601429", "keywords": "Antarctica; Climate; Deuterium; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hydrogen; Ice; Ice Core; Ice Core Chemistry; Oxygen; Paleoclimate; Snow/ice; Snow/Ice; South Pole; Stable Isotopes", "people": "Jones, Tyler R.; White, James; Vaughn, Bruce; Morris, Valerie; Kahle, Emma; Schauer, Andrew; Steig, Eric J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Continuous-flow measurements of the complete water isotope ratios (D/H, 17O/16O, 18O/16) from the South Pole ice core", "url": "https://www.usap-dc.org/view/dataset/601429"}, {"dataset_uid": "601239", "doi": "10.15784/601239", "keywords": "Antarctica; Cavity Ring Down Spectrometers; Delta 18O; Delta Deuterium; Deuterium Isotopes; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core; Ice Core Chemistry; Ice Core Data; Oxygen Isotope; Snow/ice; Snow/Ice; Stable Isotopes", "people": "Steig, Eric J.; Schauer, Andrew; Kahle, Emma; Vaughn, Bruce; Morris, Valerie; Jones, Tyler R.; White, James", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole high resolution ice core water stable isotope record for dD, d18O", "url": "https://www.usap-dc.org/view/dataset/601239"}, {"dataset_uid": "601851", "doi": "10.15784/601851", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Sea Salt and Major Ions", "url": "https://www.usap-dc.org/view/dataset/601851"}, {"dataset_uid": "601850", "doi": "10.15784/601850", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Holocene Major Ion Dataset", "url": "https://www.usap-dc.org/view/dataset/601850"}, {"dataset_uid": "601396", "doi": "10.15784/601396", "keywords": "Accumulation; Antarctica; Diffusion Length; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Dynamic; Layer Thinning; Oxygen Isotope; South Pole; SPICEcore; Temperature", "people": "Conway, Howard; Stevens, Max; Steig, Eric J.; Schauer, Andrew; Vaughn, Bruce; Morris, Valerie; Kahle, Emma; Koutnik, Michelle; Fudge, T. J.; Buizert, Christo; White, James; Epifanio, Jenna; Jones, Tyler R.; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "url": "https://www.usap-dc.org/view/dataset/601396"}], "date_created": "Sun, 17 Nov 2019 00:00:00 GMT", "description": "This project will develop a record of the stable-isotope ratios of water from an ice core at the South Pole, Antarctica. Water-isotope ratio measurements provide a means to determine variability in temperature through time. South Pole is distinct from most other locations in Antarctica in showing no warming in recent decades, but little is known about temperature variability in this location prior to the installation of weather stations in 1957. The measurements made as part of this project will result in a much longer temperature record, extending at least 40,000 years, aiding our ability to understand what controls Antarctic climate, and improving projections of future Antarctic climate change. Data from this project will be critical to other investigators working on the South Pole ice core, and of general interest to other scientists and the public. Data will be provided rapidly to other investigators and made public as soon as possible. This project will obtain records of the stable-isotope ratios of water on the ice core currently being obtained at South Pole. The core will reach a depth of 1500 m and an age of 40,000 years. The project will use laser spectroscopy to obtain both an ultra-high-resolution record of oxygen 18/16 and deuterium-hydrogen ratios, and a lower-resolution record of oxygen 17/16 ratios. The high-resolution measurements will be used to aid in dating the core, and to provide estimates of isotope diffusion that constrain the process of firn densification. The novel 17/16 measurement provides additional constraints on the isotope fractionation due to the temperature-dependent supersaturation ratio, which affects the fractionation of water during the liquid-solid condensate transition. Together, these techniques will allow for improved accuracy in the use of the water isotope ratios as proxies for ice-sheet temperature, sea-surface temperature, and atmospheric circulation. The result will be a record of decadal through centennial and millennial scale climate change in a climatically distinct region in East Antarctica that has not been previously sampled by deep ice coring. The project will support a graduate student who will be co-advised by faculty at the University of Washington and the University of Colorado, and will be involved in all aspects of the work.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "SPICEcore; D18O; LABORATORY; OXYGEN ISOTOPE ANALYSIS; Oxygen Isotope; South Pole; USAP-DC; GLACIERS/ICE SHEETS; Antarctica; AMD; FIELD INVESTIGATION; Ice Core", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Steig, Eric J.; White, James", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: Record of the Triple-oxygen Isotope and Hydrogen Isotope Composition of Ice from an Ice Core at South Pole", "uid": "p0010065", "west": 0.0}, {"awards": "1443566 Bay, Ryan", "bounds_geometry": "POINT(90 -90)", "dataset_titles": "Laser Dust Logging of the South Pole Ice Core (SPICE)", "datasets": [{"dataset_uid": "601222", "doi": "10.15784/601222", "keywords": "Antarctica; Dust; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Data; Ice Core Records; Paleoclimate; Snow/ice; Snow/Ice; SPICEcore", "people": "Bay, Ryan", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Laser Dust Logging of the South Pole Ice Core (SPICE)", "url": "https://www.usap-dc.org/view/dataset/601222"}], "date_created": "Thu, 31 Oct 2019 00:00:00 GMT", "description": "Bay/1443566 This award supports the deployment and analysis of data from an oriented laser dust logger in the South Pole ice core borehole to complement study of the ice core record. Before the core is even processed, data from the borehole probe will immediately determine the depth-age relationship, augment 3D mapping of South Pole stratigraphy, aid in searches for the oldest ice in Antarctica, and reveal layers of volcanic or extraterrestrial fallout. Regarding the intellectual merit, the oriented borehole log will be essential for investigating features in the ice sheet that may have implications for ice core chronology, ice flow, ice sheet physical properties and stability in response to climate change. The tools and techniques developed in this program have applications in glaciology, biogeoscience and exploration of other planetary bodies. The program aims for a deeper understanding of the consequences and causes of abrupt climate change. The broader impacts of the project are that it will include outreach and education, providing a broad training ground for students and post-docs. Data and metadata will be made available through data centers and repositories such as the National Snow and Ice Data Center web portal. The laser dust logger detects reproducible paleoclimate features at sub-centimeter depth scale. Dust logger data are being used for synchronizing records and dating any site on the continent, revealing accumulation anomalies and episodes of rapid ice sheet thinning, and discovering particulate horizons of special interest. In this project we will deploy a laser dust logger equipped with a magnetic compass to find direct evidence of preferentially oriented dust. Using optical scattering measurements from IceCube calibration studies at South Pole and borehole logs at WAIS Divide, we have detected a persistent anisotropy correlated with flow and crystal fabric which suggests that the majority of insoluble particulates must be located within ice grains. With typical concentrations of parts-per-billion, little is known about the location of impurities within the polycrystalline structure of polar ice. While soluble impurities are generally thought to concentrate at inter-grain boundaries and determine electrical conductivity, the fate of insoluble particulates is much less clear, and microscopic examinations are extremely challenging. These in situ borehole measurements will help to unravel intimate relationships between impurities, flow, and crystal fabric. Data from this project will further develop a unique record of South Pole surface roughness as a proxy for paleowind and provide new insights for understanding glacial radar propagation. This project has field work in Antarctica.", "east": 90.0, "geometry": "POINT(90 -90)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; Antarctica; ICE CORE RECORDS; USAP-DC", "locations": "Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bay, Ryan", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Laser Dust Logging of a South Pole Ice Core", "uid": "p0010061", "west": 90.0}, {"awards": "1543267 Brook, Edward J.; 1543229 Severinghaus, Jeffrey", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Multi-site ice core Krypton stable isotope ratios; Noble Gas Data from recent ice in Antarctica for 86Kr problem", "datasets": [{"dataset_uid": "601195", "doi": "10.15784/601195", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Krypton; Noble Gas; Xenon", "people": "Severinghaus, Jeffrey P.; Shackleton, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Noble Gas Data from recent ice in Antarctica for 86Kr problem", "url": "https://www.usap-dc.org/view/dataset/601195"}, {"dataset_uid": "601394", "doi": "10.15784/601394", "keywords": "Antarctica; Bruce Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland Ice Cap; Ice Core; Ice Core Chemistry; Ice Core Records; James Ross Island; Krypton; Law Dome; Low Dome Ice Core; Roosevelt Island; Siple Dome; Siple Dome Ice Core; South Pole; SPICEcore; WAIS Divide; WAIS Divide Ice Core", "people": "Bertler, Nancy; Etheridge, David; Shackleton, Sarah; Pyne, Rebecca L.; Buizert, Christo; Mulvaney, Robert; Severinghaus, Jeffrey P.; Brook, Edward J.; Baggenstos, Daniel; Mosley-Thompson, Ellen; Bereiter, Bernhard", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Multi-site ice core Krypton stable isotope ratios", "url": "https://www.usap-dc.org/view/dataset/601394"}, {"dataset_uid": "601394", "doi": "10.15784/601394", "keywords": "Antarctica; Bruce Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland Ice Cap; Ice Core; Ice Core Chemistry; Ice Core Records; James Ross Island; Krypton; Law Dome; Low Dome Ice Core; Roosevelt Island; Siple Dome; Siple Dome Ice Core; South Pole; SPICEcore; WAIS Divide; WAIS Divide Ice Core", "people": "Etheridge, David; Brook, Edward J.; Bereiter, Bernhard; Severinghaus, Jeffrey P.; Bertler, Nancy; Buizert, Christo; Shackleton, Sarah; Baggenstos, Daniel; Pyne, Rebecca L.; Mulvaney, Robert; Mosley-Thompson, Ellen", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Multi-site ice core Krypton stable isotope ratios", "url": "https://www.usap-dc.org/view/dataset/601394"}, {"dataset_uid": "601394", "doi": "10.15784/601394", "keywords": "Antarctica; Bruce Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland Ice Cap; Ice Core; Ice Core Chemistry; Ice Core Records; James Ross Island; Krypton; Law Dome; Low Dome Ice Core; Roosevelt Island; Siple Dome; Siple Dome Ice Core; South Pole; SPICEcore; WAIS Divide; WAIS Divide Ice Core", "people": "Severinghaus, Jeffrey P.; Bertler, Nancy; Pyne, Rebecca L.; Shackleton, Sarah; Buizert, Christo; Mulvaney, Robert; Mosley-Thompson, Ellen; Etheridge, David; Bereiter, Bernhard; Baggenstos, Daniel; Brook, Edward J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Multi-site ice core Krypton stable isotope ratios", "url": "https://www.usap-dc.org/view/dataset/601394"}], "date_created": "Wed, 10 Jul 2019 00:00:00 GMT", "description": "Brook 1543267 Approximately half of the human caused carbon dioxide emissions to the atmosphere are absorbed by the ocean, which reduces the amount of global warming associated with these emissions. Much of this carbon uptake occurs in the Southern Ocean around Antarctica, where water from the deep ocean comes to the surface. How much water \"up-wells,\" and therefore how much carbon is absorbed, is believed to depend on the strength and location of the major westerly winds in the southern hemisphere. These wind patterns have been shifting southward in recent decades, and future changes could impact the global carbon cycle and promote the circulation of relatively warm water from the deep ocean on to the continental shelf, which contributes to enhanced Antarctic ice melt and sea level rise. Understanding of the westerly winds and their role in controlling atmospheric carbon dioxide levels and the circulation of ocean water is therefore very important. The work supported by this award will study past movement of the SH westerlies in response to natural climate variations. Of particular interest is the last deglaciation (20,000 to 10,000 years ago), when the global climate made a transition from an ice age climate to the current warm period. During this period, atmospheric carbon dioxide rose from about 180 ppm to 270 parts per million, and one leading hypothesis is that the rise in carbon dioxide was driven by a southward movement of the southern hemisphere westerlies. The broader impacts of the work include a perspective on past movement of the southern hemisphere westerlies and their link to atmospheric carbon dioxide, which could guide projections of future oceanic carbon dioxide uptake, with strong societal benefits; international collaboration with German scientists; training of a postdoctoral investigator; and outreach to public schools. This project will investigate whether the abundance of a noble gas, krypton-86, trapped in Antarctic ice cores, records atmospheric pressure variability, and whether or not this pressure variability can be used to infer past movement of the Southern Hemisphere westerly winds. The rationale for the project is that models of air movement in the snow pack (firn) in Antarctica indicate that pressure variations drive air movement that disturbs the normal enrichment in krypton-86 caused by gravitational settling of gases. Calculations predict that the krypton-86 deviation from gravitational equilibrium reflects the magnitude of pressure variations. In turn, atmospheric data show that pressure variability over Antarctica is linked to the position of the southern hemisphere westerly winds. Preliminary data from the West Antarctic Ice Sheet (WAIS) Divide ice core show a large excursion in krypton-86 during the transition from the last ice age to the current warm period. The investigators will perform krypton-86 analysis on ice core and firn air samples to establish whether the Kr-86 deviation is linked to pressure variability, refine the record of krypton isotopes from the WAIS Divide ice core, investigate the role of pressure variability in firn air transport using firn air models, and investigate how barometric pressure variability in Antarctica is linked to the position/strength of the SH westerlies in past and present climates.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USA/NSF; FIRN; ICE CORE RECORDS; USAP-DC; Greenland; Xenon; Noble Gas; Ice Core; Amd/Us; Antarctica; AMD; LABORATORY; Krypton; ATMOSPHERIC PRESSURE", "locations": "Greenland; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.; Brook, Edward J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative research: Kr-86 as a proxy for barometric pressure variability and movement of the SH westerlies during the last\r\ndeglaciation", "uid": "p0010037", "west": -180.0}, {"awards": "1822289 Vernet, Maria; 1822256 Smith, Craig", "bounds_geometry": "POLYGON((-59.5 -62,-59.05 -62,-58.6 -62,-58.15 -62,-57.7 -62,-57.25 -62,-56.8 -62,-56.35 -62,-55.9 -62,-55.45 -62,-55 -62,-55 -62.27,-55 -62.54,-55 -62.81,-55 -63.08,-55 -63.35,-55 -63.62,-55 -63.89,-55 -64.16,-55 -64.43,-55 -64.7,-55.45 -64.7,-55.9 -64.7,-56.35 -64.7,-56.8 -64.7,-57.25 -64.7,-57.7 -64.7,-58.15 -64.7,-58.6 -64.7,-59.05 -64.7,-59.5 -64.7,-59.5 -64.43,-59.5 -64.16,-59.5 -63.89,-59.5 -63.62,-59.5 -63.35,-59.5 -63.08,-59.5 -62.81,-59.5 -62.54,-59.5 -62.27,-59.5 -62))", "dataset_titles": "CTD stations and logs for Araon 2018 ANA08D expedition to Larson C; Yoyo camera survey transects, King George Island and Bransfield Strait", "datasets": [{"dataset_uid": "601178", "doi": "10.15784/601178", "keywords": "Antarctica; Biota; Chlorophyll; CTD; Glacier; Iceberg; Ice Shelf; Larsen C Ice Shelf; Oceans; Physical Oceanography; Phytoplankton; Sample Location; Sea Ice; Southern Ocean; Station List", "people": "Pan, B. Jack; Vernet, Maria", "repository": "USAP-DC", "science_program": null, "title": "CTD stations and logs for Araon 2018 ANA08D expedition to Larson C", "url": "https://www.usap-dc.org/view/dataset/601178"}, {"dataset_uid": "601199", "doi": "10.15784/601199", "keywords": "Antarctica; Araon; Araon Ana08d; Benthic Images; Benthos; Photo/video; Photo/Video; Southern Ocean; Station List; Yoyo Camera", "people": "Smith, Craig; Ziegler, Amanda", "repository": "USAP-DC", "science_program": null, "title": "Yoyo camera survey transects, King George Island and Bransfield Strait", "url": "https://www.usap-dc.org/view/dataset/601199"}], "date_created": "Wed, 15 May 2019 00:00:00 GMT", "description": "Marine ecosystems under large ice shelves are thought to contain sparse, low-diversity plankton and seafloor communities due the low supply of food from productive sunlight waters. Past studies have shown sub-ice shelf ecosystems to change in response to altered oceanographic processes resulting from ice-shelve retreat. However, information on community changes and ecosystem structure under ice shelves are limited because sub-ice-shelf ecosystems have either been sampled many years after ice-shelf breakout, or have been sampled through small boreholes, yielding extremely limited spatial information. The recent breakout of the A-68 iceberg from the Larsen C ice shelf in the western Weddell Sea provides an opportunity to use a ship-based study to evaluate benthic communities and water column characteristics in an area recently vacated by a large overlying ice shelf. The opportunity will allow spatial assessments at the time of transition from an under ice-shelf environment to one initially exposed to conditions more typical of a coastal Antarctic marine setting. This RAPID project will help determine the state of a coastal Antarctic ecosystem newly exposed from ice-shelf cover and will aid in understanding of rates of community change during transition. The project will conduct a 10-day field program, allowing contrasts to be made of phytoplankton and seafloor megafaunal communities in areas recently exposed by ice-shelf loss to areas exposed for many decades. The project will be undertaken in a collaborative manner with the South Korean Antarctic Agency, KOPRI, by participating in a cruise in March/May 2018. Combining new information in the area of Larsen C with existing observations after the Larsen A and B ice shelf breakups further to the north, the project is expected to generate a dataset that can elucidate fundamental processes of planktonic and benthic community development in transition from food-poor to food-rich ecosystems. The project will provide field experience to two graduate students, a post-doctoral associate and an undergraduate student. Material from the project will be incorporated into graduate courses and the project will communicate daily work and unfolding events through social media and blogs while they explore this area of the world that is largely underexplored. 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": -55.0, "geometry": "POINT(-57.25 -63.35)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Antarctica; R/V NBP; Sea Floor; ANIMALS/INVERTEBRATES; ICEBERGS; USAP-DC", "locations": "Antarctica; Sea Floor", "north": -62.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Vernet, Maria; Smith, Craig", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.7, "title": "RAPID: Collaborative Research: Marine Ecosystem Response to the Larsen C Ice-Shelf Breakout: \"Time zero\"", "uid": "p0010029", "west": -59.5}, {"awards": "1341479 Marchetti, Adrian", "bounds_geometry": "POLYGON((-72.8 -48,-67.12 -48,-61.44 -48,-55.76 -48,-50.08 -48,-44.4 -48,-38.72 -48,-33.04 -48,-27.36 -48,-21.68 -48,-16 -48,-16 -50.02,-16 -52.04,-16 -54.06,-16 -56.08,-16 -58.1,-16 -60.12,-16 -62.14,-16 -64.16,-16 -66.18,-16 -68.2,-21.68 -68.2,-27.36 -68.2,-33.04 -68.2,-38.72 -68.2,-44.4 -68.2,-50.08 -68.2,-55.76 -68.2,-61.44 -68.2,-67.12 -68.2,-72.8 -68.2,-72.8 -66.18,-72.8 -64.16,-72.8 -62.14,-72.8 -60.12,-72.8 -58.1,-72.8 -56.08,-72.8 -54.06,-72.8 -52.04,-72.8 -50.02,-72.8 -48))", "dataset_titles": "16S and 18S Sequence data; Fragilariopsis kerguelensis iron and light transcriptomes; Physiology and transcriptomes of polar isolates; Polar isolate transcriptomes; Sequence data from Ocean Station Papa seawater ; Sequence data RNA-Seq of marine phytoplankton: FeB12", "datasets": [{"dataset_uid": "200016", "doi": "", "keywords": null, "people": null, "repository": "iMicrobe", "science_program": null, "title": "Fragilariopsis kerguelensis iron and light transcriptomes", "url": "https://www.imicrobe.us/#/projects/104"}, {"dataset_uid": "200021", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "16S and 18S Sequence data", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA299401"}, {"dataset_uid": "200020", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Physiology and transcriptomes of polar isolates", "url": "https://www.bco-dmo.org/project/653229"}, {"dataset_uid": "200019", "doi": "", "keywords": null, "people": null, "repository": "Cyverse Data Commons", "science_program": null, "title": "Polar isolate transcriptomes", "url": "http://datacommons.cyverse.org/search/?search_term=unc_phyto_isolates"}, {"dataset_uid": "200018", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Sequence data from Ocean Station Papa seawater ", "url": "https://www.ncbi.nlm.nih.gov/sra/SRP006906"}, {"dataset_uid": "200017", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Sequence data RNA-Seq of marine phytoplankton: FeB12", "url": "https://www.ncbi.nlm.nih.gov/sra/SRP074366"}], "date_created": "Mon, 11 Mar 2019 00:00:00 GMT", "description": "The Southern Ocean surrounding Antarctica is changing rapidly in response to Earth\u0027s warming climate. These changes will undoubtedly influence communities of primary producers (the organisms at the base of the food chain, particularly plant-like organisms using sunlight for energy) by altering conditions that influence their growth and composition. Because primary producers such as phytoplankton play an important role in global biogeochemical cycling, it is essential to understand how they will respond to changes in their environment. The growth of phytoplankton in certain regions of the Southern Ocean is constrained by steep gradients in chemical and physical properties that vary in both space and time. Light and iron have been identified as key variables influencing phytoplankton abundance and distribution within Antarctic waters. Microscopic algae known as diatoms are dominant members of the phytoplankton and sea ice communities, accounting for significant proportions of primary production. The overall objective of this project is to identify the molecular bases for the physiological responses of polar diatoms to varying light and iron conditions. The project should provide a means of evaluating the extent these factors regulate diatom growth and influence net community productivity in Antarctic waters. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. It will facilitate the teaching and learning of polar-related topics by translating the research objectives into readily accessible educational materials for middle-school students. This project will also provide funding to enable a graduate student and several undergraduate students to be trained in the techniques and perspectives of modern biology. Although numerous studies have investigated how polar diatoms are affected by varying light and iron, the cellular mechanisms leading to their distinct physiological responses remain unknown. Using comparative transcriptomics, the expression patterns of key genes and metabolic pathways in several ecologically important polar diatoms recently isolated from Antarctic waters and grown under varying iron and irradiance conditions will be examined. In addition, molecular indicators for iron and light limitation will be developed within these polar diatoms through the identification of iron- and light-responsive genes -- the expression patterns of which can be used to determine their physiological status. Upon verification in laboratory cultures, these indicators will be utilized by way of metatranscriptomic sequencing to examine iron and light limitation in natural diatom assemblages collected along environmental gradients in Western Antarctic Peninsula waters. In order to fully understand the role phytoplankton play in Southern Ocean biogeochemical cycles, dependable methods that provide a means of elucidating the physiological status of phytoplankton at any given time and location are essential.", "east": -16.0, "geometry": "POINT(-44.4 -58.1)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; AQUATIC SCIENCES; PHYTOPLANKTON; USAP-DC; Southern Ocean; Sea Surface; DIATOMS", "locations": "Sea Surface; Southern Ocean", "north": -48.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Marchetti, Adrian", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "iMicrobe", "repositories": "BCO-DMO; Cyverse Data Commons; iMicrobe; NCBI GenBank", "science_programs": null, "south": -68.2, "title": "Iron and Light Limitation in Ecologically Important Polar Diatoms: Comparative Transcriptomics and Development of Molecular Indicators", "uid": "p0010018", "west": -72.8}, {"awards": "1245766 Waller, Rhian", "bounds_geometry": "POINT(-63.0796667 -61.5157)", "dataset_titles": "Expedition Data; Log Sheets of coral samples for LMG1509", "datasets": [{"dataset_uid": "601160", "doi": "10.15784/601160", "keywords": "Antarctica; Antarctic Peninsula; Biota; Corals; CTD; LMG1509; Oceans; Otter Trawl; R/v Laurence M. Gould; Sample/collection Description; Sample/Collection Description; Sample Location; Southern Ocean", "people": "Waller, Rhian", "repository": "USAP-DC", "science_program": null, "title": "Log Sheets of coral samples for LMG1509", "url": "https://www.usap-dc.org/view/dataset/601160"}, {"dataset_uid": "001378", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1509"}], "date_created": "Thu, 07 Mar 2019 00:00:00 GMT", "description": "The Western Antarctic Peninsula is experiencing climate change at one of the fastest rates of anywhere around the globe. Accelerated climate change is likely to affect the many benthic marine invertebrates that live within narrow temperature windows along the Antarctic Continental Shelf in presently unidentified ways. At present however, there are few data on the physiological consequences of climate change on the sensitive larval stages of cold-water corals, and none on species living in thermal extremes such as polar waters. This project will collect the larvae of the non-seasonal, brooding scleractinian Flabellum impensum to be used in a month-long climate change experiment at Palmer Station. Multidisciplinary techniques will be used to examine larval development and cellular stress using a combination of electron microscopy, flow cytometry, and Inductively Coupled Plasma Mass Spectometry. Data from this project will form the first systematic study of the larval stages of polar cold-water corals, and how these stages are affected by temperature stress at the cellular and developmental level. Cold-water corals have been shown to be important ecosystem engineers, providing habitat for thousands of associated species, including many that are of commercial importance. Understanding how the larvae of these corals react to warming trends seen today in our oceans will allow researchers to predict future changes in important benthic communities around the globe. Associated education and outreach include: 1) Increasing student participation in polar research by involving postdoctoral and undergraduate students in the field and research program; ii) promotion of K-12 teaching and learning programs by providing information via a research website, Twitter, and in-school talks in the local area; iii) making the data collected available to the wider research community via peer reviewed published literature and iv) reaching a larger public audience through such venues as interviews in the popular media, You Tube and other popular media outlets, and local talks to the general public.", "east": -63.0796667, "geometry": "POINT(-63.0796667 -61.5157)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e TRAWLS/NETS \u003e OTTER TRAWL", "is_usap_dc": true, "keywords": "AQUATIC SCIENCES; ANIMALS/INVERTEBRATES; R/V LMG; Southern Ocean; USAP-DC; WATER TEMPERATURE", "locations": "Southern Ocean", "north": -61.5157, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Waller, Rhian; Jay, Lunden", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -61.5157, "title": "Cold Corals in Hot Water - Investigating the Physiological Responses of Antarctic Coral Larvae to Climate change Stress", "uid": "p0010017", "west": -63.0796667}, {"awards": "1443347 Condron, Alan; 1443394 Pollard, 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": "Antarctic Ice Sheet simulations for role of freshwater in future warming scenarios; Future climate response to Antarctic Ice Sheet melt caused by anthropogenic warming; Simulated changes in Southern Ocean salinity", "datasets": [{"dataset_uid": "601449", "doi": "10.15784/601449", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Meltwater", "people": "Condron, Alan", "repository": "USAP-DC", "science_program": null, "title": "Future climate response to Antarctic Ice Sheet melt caused by anthropogenic warming", "url": "https://www.usap-dc.org/view/dataset/601449"}, {"dataset_uid": "601154", "doi": "10.15784/601154 ", "keywords": "Antarctic; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Ice Sheet Model; Meltwater; Model Data; Modeling; Model Output", "people": "Pollard, David", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Ice Sheet simulations for role of freshwater in future warming scenarios", "url": "https://www.usap-dc.org/view/dataset/601154"}, {"dataset_uid": "601442", "doi": "10.15784/601442", "keywords": "Antarctica; Computer Model; Freshwater; Glaciers/ice Sheet; Glaciers/Ice Sheet; Model Data; Ocean Model; Oceans; Salinity", "people": "Condron, Alan", "repository": "USAP-DC", "science_program": null, "title": "Simulated changes in Southern Ocean salinity", "url": "https://www.usap-dc.org/view/dataset/601442"}], "date_created": "Mon, 04 Feb 2019 00:00:00 GMT", "description": "There is compelling historical evidence that the West Antarctic Ice Sheet (WAIS) is vulnerable to rapid retreat and collapse. Recent observations, compared to observations made 20-30 years before, indicate that both ice shelves (thick ice with ocean below) and land ice (thick ice with land below), are now melting at a much faster rate. Some numerical models suggest that significant ice retreat may begin within many of our lifetimes, starting with the abrupt collapse of Pine Island and Thwaites Glaciers in the next 50 years. This may be followed by retreat of much of the WAIS and then the collapse of parts of the East Antarctic ice sheet (EAIS). This research project will assess the extent to which global ocean circulation and climate will be impacted if enormous volumes of fresh water and ice flow into the Southern Ocean. It will establish whether a rapid collapse of WAIS in the near-future poses any significant threat to the stability of modern-day climate and human society. This is a topic that has so far received little attention as most prior research has focused on the response of climate to melting the Greenland ice sheet. Yet model simulations predict that the volumes of fresh water and ice released from Antarctica in the next few centuries could be up at least ten-times larger than from Greenland. The Intellectual Merit of this project stems from its ability to establish a link between the physical Antarctic system (ice sheet dynamics, fresh water discharge and iceberg calving) and global climate. The PIs (Principal Investigators) will assess the sensitivity of ocean circulation and climate to increased ice sheet melt using a combination of ocean, iceberg, ice sheet and climate models. Results from this study will help identify areas of the ice sheet that are vulnerable to collapse and also regions of the ocean where a significant freshening will have a considerable impact on climate, and serve to guide the deployment of an observational monitoring system capable of warning us when ice and fresh water discharge start to approach levels capable of disrupting ocean circulation and global climate. This project will support and train two graduate students, and each PI will be involved with local primary and secondary schools, making presentations, mentoring science fair projects, and contributing to curriculum development. A novel, web-based, interactive, cryosphere learning tool will be developed to help make school children more aware of the importance of the Polar Regions in global climate, and this software will be introduced to science teachers at a half day workshop organized by the UMass STEM Education Institute. Recent numerical simulations using a continental ice sheet/shelf model show the potential for more rapid and greater Antarctic ice sheet retreat in the next 50-300 years (under the full range of IPCC RCP (Intergovernmental Panel on Climate Change, Representative Concentration Pathways) future warming scenarios) than previously projected. Exactly how the release of enormous volumes of ice and fresh water to the Southern Ocean will impact global ocean circulation and climate has yet to be accurately assessed. This is in part because previous model simulations were too coarse to accurately resolve narrow coastal boundary currents, shelf breaks, fronts, and mesoscale eddies that are all very important for realistically simulating fresh water transport in the ocean. In this award, future projections of fresh water discharge and iceberg calving from Antarctic will be used to force a high resolution eddy-resolving ocean model (MITgcm) coupled to a new iceberg module and a fully-coupled global climate model (CCSM4). High resolution ocean/iceberg simulations will determine the role of mesoscale eddies in freshwater transport and give new insight into how fresh water is advected to far-field locations, including deep water formation sites in the North Atlantic. These simulations will provide detailed information about subsurface temperatures and changes in ocean circulation close to the ice front and grounding line. An accompanying set of fully coupled climate model simulations (NCAR CCSM4) will identify multidecadal-to-centennial changes in the climate system triggered by increased high-latitude Southern Ocean freshwater forcing. Particular attention will be given to changes in the strength of the Atlantic Meridional Overturning Circulation (AMOC), wind stress, sea ice formation, and global temperatures. In doing so, this project will more accurately determine whether abrupt and potentially catastrophic changes in global climate are likely to be triggered by changes in the Antarctic system in the near-future.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e DATA ANALYSIS \u003e ENVIRONMENTAL MODELING \u003e COMPUTER", "is_usap_dc": true, "keywords": "USAP-DC; USA/NSF; AMD; MODELS; Amd/Us; Antarctica; GLACIERS/ICE SHEETS", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Pollard, David; Condron, Alan; DeConto, Robert", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Assessing the Global Climate Response to Melting of the Antarctic Ice Sheet", "uid": "p0010007", "west": -180.0}, {"awards": "1246293 Saba, Grace", "bounds_geometry": null, "dataset_titles": "2014 Antarctic krill growth experiment - submitted", "datasets": [{"dataset_uid": "002572", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "2014 Antarctic krill growth experiment - submitted", "url": "https://www.bco-dmo.org/project/721363"}], "date_created": "Fri, 14 Sep 2018 00:00:00 GMT", "description": "Climate change projections for this century suggest that the Southern Ocean will be the first region to be affected by seawater chemistry changes associated with enhanced carbon dioxide (CO2). Additionally, regions of the Southern Ocean are warming faster than any other locations on the planet. Ocean acidification and warming may act synergistically to impair the performance of different organisms by simultaneously increasing metabolic needs and reducing oxygen transport. However, no studies have measured krill acid-base regulation, metabolism, growth, or reproduction in the context of ocean acidification or synergistic \u0027greenhouse\u0027 conditions of elevated CO2 and temperature. In the present project, the investigators will conduct both short and prolonged exposure experiments at Palmer Station, Antarctica to determine the responses of Euphausia superba to elevated CO2 and temperature. The investigators will test hypotheses related to acid-base compensation and acclimation of various life stages of krill to elevated CO2 and temperature. Furthermore, they will determine these impacts on feeding, respiration, metabolism, growth, and reproduction. The Antarctic krill, Euphausia superba, is a key component of Antarctic food webs as they are a primary food source for many of the top predators in the Southern Ocean including baleen whales, seals, penguins, and other sea birds. This project will determine the responses of Antarctic krill exposed to elevated CO2 and temperature and whether or not krill have the capacity to fully compensate under future ocean conditions. The proposed field effort will be complemented by an extensive broader impact effort focused on bringing marine science to both rural and urban high school students in the Midwest (Kansas). The core educational objectives of this proposal are to 1) instruct students about potential careers in marine science, 2) engage students and promote their interest in the scientific process, critical thinking, and applications of science, mathematics, and technology, and 3) and increase student and teacher awareness and understanding of the oceans and global climate change, with special focus on the Western Antarctic Peninsula region. Finally, this project will engage undergraduate and graduate students in the production, analysis, presentation and publication of datasets.", "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": "Saba, Grace", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": null, "title": "Collaborative Research: Synergistic effects of Elevated Carbon Dioxide (CO2) and Temperature on the Metabolism, Growth, and Reproduction of Antarctic Krill (Euphausia Superba)", "uid": "p0000700", "west": null}, {"awards": null, "bounds_geometry": null, "dataset_titles": "Location of surface crevasses in Antarctica", "datasets": [{"dataset_uid": "601117", "doi": "10.15784/601117", "repository": "USAP-DC", "science_program": null, "title": "Location of surface crevasses in Antarctica", "url": "http://www.usap-dc.org/view/dataset/601117"}], "date_created": "Wed, 05 Sep 2018 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Crevasses; Fractures; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Ice Shelf; Satellite Remote Sensing", "locations": "Antarctica", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Emetc, Veronika", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "1341669 DeMaster, David", "bounds_geometry": "POLYGON((-70 -62,-68.8 -62,-67.6 -62,-66.4 -62,-65.2 -62,-64 -62,-62.8 -62,-61.6 -62,-60.4 -62,-59.2 -62,-58 -62,-58 -62.6,-58 -63.2,-58 -63.8,-58 -64.4,-58 -65,-58 -65.6,-58 -66.2,-58 -66.8,-58 -67.4,-58 -68,-59.2 -68,-60.4 -68,-61.6 -68,-62.8 -68,-64 -68,-65.2 -68,-66.4 -68,-67.6 -68,-68.8 -68,-70 -68,-70 -67.4,-70 -66.8,-70 -66.2,-70 -65.6,-70 -65,-70 -64.4,-70 -63.8,-70 -63.2,-70 -62.6,-70 -62))", "dataset_titles": "DeMaster Compiled Larsen Ice Shelf and the West Antarctic Peninsula C14 Data; Expedition Data of NBP1203; Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf; Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf; Species Abundance Data from the Larsen Ice Shelf Ice acquired during R/V Nathaniel B. Palmer expedition NBP1203", "datasets": [{"dataset_uid": "001438", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1203", "url": "https://www.rvdata.us/search/cruise/NBP1203"}, {"dataset_uid": "601304", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; Megafauna; NBP1203; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Species Abundance Data from the Larsen Ice Shelf Ice acquired during R/V Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601304"}, {"dataset_uid": "601319", "doi": "10.15784/601319", "keywords": "Antarctica; Antarctic Peninsula; Biota; Bioturbation Coefficients; Diagenesis; Labile Organic Carbon; LOC Mean Residence Times; Marguerite Bay; Oceans; Organic Carbon Degradation Rates; Sediment Core", "people": "Taylor, Richard; Smith, Craig; Isla, Enrique; Thomas, Carrie; DeMaster, David", "repository": "USAP-DC", "science_program": null, "title": "Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf", "url": "https://www.usap-dc.org/view/dataset/601319"}, {"dataset_uid": "601336", "doi": "10.15784/601336", "keywords": "Antarctica; Carbon-14; Larsen Ice Shelf; Lead-210; Marine Sediments; Radioisotope Analysis", "people": "Taylor, Richard; DeMaster, David", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/601336"}, {"dataset_uid": "601082", "doi": "10.15784/601082", "keywords": null, "people": "DeMaster, David", "repository": "USAP-DC", "science_program": "LARISSA", "title": "DeMaster Compiled Larsen Ice Shelf and the West Antarctic Peninsula C14 Data", "url": "https://www.usap-dc.org/view/dataset/601082"}], "date_created": "Sat, 03 Feb 2018 00:00:00 GMT", "description": "Intellectual Merit: The PI requests support to analyze sediments from multi-cores and mega-cores previously collected from beneath the former Larsen B and Larsen A ice shelves. These unique cores will allow the PI to develop a time-integrated understanding of the benthic response to ice shelf collapse off the East Antarctic Peninsula over time periods as short as 5 years following ice shelf collapse up to \u003e170 years after collapse. High latitudes are responding to climate change more rapidly than the rest of the planet and the disappearance of ice shelves are a key manifestation of climate warming. The PI will investigate the newly created benthic environments and associated ecosystems that have resulted from the re-initiation of fresh planktonic material to the sediment-water interface. This proposal will use a new geochemical technique, based on naturally occurring 14C that can be used to assess the distribution and inventory of recently produced organic carbon accumulating in the sediments beneath the former Larsen A and B ice shelves. The PI will couple 14C measurements with 210Pb analyses to assess turnover times for sedimentary labile organic matter. By comparing the distributions and inventories of labile organic matter as well as the bioturbation intensities among different locations as a function of time following ice shelf collapse/retreat, the nature and timing of the benthic response to ice shelf collapse can be assessed. Broader impacts: This study will provide important information characterizing changes occurring on the seafloor after the collapse of ice shelves. This research will support the research project of a graduate student. This project brings together researchers from both the European community and the LARISSA Project.", "east": -58.0, "geometry": "POINT(-64 -65)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Pb-210; C-14; NBP1203; Radioisotop; USAP-DC; R/V NBP; Species Abundance; Labile Organic Carbon; LABORATORY", "locations": null, "north": -62.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Instrumentation and Support", "paleo_time": null, "persons": "DeMaster, David; Smith, Craig", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": "LARISSA", "south": -68.0, "title": "Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change", "uid": "p0000382", "west": -70.0}, {"awards": "0732711 Smith, Craig; 0732655 Mosley-Thompson, Ellen; 0732983 Vernet, Maria; 0732651 Gordon, Arnold; 0732625 Leventer, Amy; 0732602 Truffer, Martin", "bounds_geometry": "POLYGON((-68 -57.8,-66.78 -57.8,-65.56 -57.8,-64.34 -57.8,-63.12 -57.8,-61.9 -57.8,-60.68 -57.8,-59.46 -57.8,-58.24 -57.8,-57.02 -57.8,-55.8 -57.8,-55.8 -58.8,-55.8 -59.8,-55.8 -60.8,-55.8 -61.8,-55.8 -62.8,-55.8 -63.8,-55.8 -64.8,-55.8 -65.8,-55.8 -66.8,-55.8 -67.8,-57.02 -67.8,-58.24 -67.8,-59.46 -67.8,-60.68 -67.8,-61.9 -67.8,-63.12 -67.8,-64.34 -67.8,-65.56 -67.8,-66.78 -67.8,-68 -67.8,-68 -66.8,-68 -65.8,-68 -64.8,-68 -63.8,-68 -62.8,-68 -61.8,-68 -60.8,-68 -59.8,-68 -58.8,-68 -57.8))", "dataset_titles": "Abrupt Environmental Change in the Larsen Ice Shelf System (LARISSA) - Marine Ecosystems; Biology Species Abundance from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expeditions NBP1001 and NBP1203; Bruce Plateau Accumulation O18 2009-1900; Easten Antarctic Peninsula Surface Sediment Diatom Data; LMG13-11 JKC-1 Paleoceanographic data; Macrofauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001; Megafauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001; NBP1001 cruise data; NBP1203 cruise data; Processed CTD Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001; Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203; Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001; Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203; Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf; Sediment samples (full data link not provided)", "datasets": [{"dataset_uid": "601345", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1001; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Processed CTD Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601345"}, {"dataset_uid": "601347", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Current Measurements; LADCP; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601347"}, {"dataset_uid": "000142", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1001 cruise data", "url": "https://www.rvdata.us/search/cruise/NBP1001"}, {"dataset_uid": "601348", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601348"}, {"dataset_uid": "000143", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1203 cruise data", "url": "https://www.rvdata.us/search/cruise/NBP1203"}, {"dataset_uid": "000145", "doi": "", "keywords": null, "people": null, "repository": "AMGRF", "science_program": null, "title": "Sediment samples (full data link not provided)", "url": "http://arf.fsu.edu/"}, {"dataset_uid": "601336", "doi": "10.15784/601336", "keywords": "Antarctica; Carbon-14; Larsen Ice Shelf; Lead-210; Marine Sediments; Radioisotope Analysis", "people": "Taylor, Richard; DeMaster, David", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/601336"}, {"dataset_uid": "601485", "doi": "10.15784/601485", "keywords": "Antarctica; Antarctic Peninsula; Delta 13C; Delta 18O; Paleoceanography; Temperature", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": "LARISSA", "title": "LMG13-11 JKC-1 Paleoceanographic data", "url": "https://www.usap-dc.org/view/dataset/601485"}, {"dataset_uid": "600073", "doi": "10.15784/600073", "keywords": "Antarctica; Antarctic Peninsula; Araon1304; Biota; LARISSA; Larsen B Ice Shelf; NBP1001; NBP1203; Oceans; Physical Oceanography; Southern Ocean; Weddell Sea", "people": "Vernet, Maria", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Abrupt Environmental Change in the Larsen Ice Shelf System (LARISSA) - Marine Ecosystems", "url": "https://www.usap-dc.org/view/dataset/600073"}, {"dataset_uid": "000226", "doi": "", "keywords": null, "people": null, "repository": "MGDS", "science_program": null, "title": "Biology Species Abundance from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expeditions NBP1001 and NBP1203", "url": "https://doi.org/10.1594/ieda/320821"}, {"dataset_uid": "601306", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; NBP1001; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Macrofauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601306"}, {"dataset_uid": "601305", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; Megafauna; NBP1001; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Megafauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601305"}, {"dataset_uid": "601211", "doi": "10.15784/601211", "keywords": "Antarctica; Antarctic Peninsula; Benthos; Biota; Diatom; Geology/Geophysics - Other; LMG0502; Marine Geoscience; Marine Sediments; Microscope; NBP0003; NBP0107; NBP0603; NBP1203; R/v Nathaniel B. Palmer; Surface Sediment", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Easten Antarctic Peninsula Surface Sediment Diatom Data", "url": "https://www.usap-dc.org/view/dataset/601211"}, {"dataset_uid": "600167", "doi": "10.15784/600167", "keywords": "Antarctica; Antarctic Peninsula; Bruce Plateau; Glaciology; Ice Core Records; Isotope; LARISSA; Paleoclimate; Sample/collection Description; Sample/Collection Description; Snow Accumulation", "people": "Mosley-Thompson, Ellen; Thompson, Lonnie G.", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Bruce Plateau Accumulation O18 2009-1900", "url": "https://www.usap-dc.org/view/dataset/600167"}, {"dataset_uid": "601346", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Current Measurements; LADCP; Larsen Ice Shelf; NBP1001; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601346"}], "date_created": "Thu, 01 Feb 2018 00:00:00 GMT", "description": "Like no other region on Earth, the northern Antarctic Peninsula represents a spectacular natural laboratory of climate change and provides the opportunity to study the record of past climate and ecological shifts alongside the present-day changes in one of the most rapidly warming regions on Earth. This award supports the cryospheric and oceano-graphic components of an integrated multi-disciplinary program to address these rapid and fundamental changes now taking place in Antarctic Peninsula (AP). By making use of a marine research platform (the RV NB Palmer and on-board helicopters) and additional logistical support from the Argentine Antarctic program, the project will bring glaciologists, oceanographers, marine geologists and biologists together, working collaboratively to address fundamentally interdisciplinary questions regarding climate change. The project will include gathering a new, high-resolution paleoclimate record from the Bruce Plateau of Graham Land, and using it to compare Holocene- and possibly glacial-epoch climate to the modern period; investigating the stability of the remaining Larsen Ice Shelf and rapid post-breakup glacier response ? in particular, the roles of surface melt and ice-ocean interactions in the speed-up and retreat; observing the contribution of, and response of, oceanographic systems to ice shelf disintegration and ice-glacier interactions. Helicopter support on board will allow access to a wide range of glacial and geological areas of interest adjacent to the Larsen embayment. At these locations, long-term in situ glacial monitoring, isostatic uplift, and ice flow GPS sites will be established, and high-resolution ice core records will be obtained using previously tested lightweight drilling equipment. Long-term monitoring of deep water outflow will, for the first time, be integrated into changes in ice shelf extent and thickness, bottom water formation, and multi-level circulation by linking near-source observations to distal sites of concentrated outflow. The broader impacts of this international, multidisciplinary effort are that it will significantly advance our understanding of linkages amongst the earth\u0027s systems in the Polar Regions, and are proposed with international participation (UK, Spain, Belgium, Germany and Argentina) and interdisciplinary engagement in the true spirit of the International Polar Year (IPY). It will also provide a means of engaging and educating the public in virtually all aspects of polar science and the effects of ongoing climate change. The research team has a long record of involving undergraduates in research, educating high-performing graduate students, and providing innovative and engaging outreach products to the K-12 education and public media forums. Moreover, forging the new links both in science and international Antarctic programs will provide a continuing legacy, beyond IPY, of improved understanding and cooperation in Antarctica.", "east": -55.8, "geometry": "POINT(-61.9 -62.8)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e BOX CORE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ICE AUGERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SNOW DENSITY CUTTER", "is_usap_dc": true, "keywords": "Paleoclimate; Megafauna; USAP-DC; AMD; Amd/Us; Antarctica; Climate Change; LABORATORY; Climate Variability; Multi-Disciplinary; Cryosphere; NBP1001; FIELD SURVEYS; Not provided; Antarctic Peninsula; R/V NBP; FIELD INVESTIGATION; USA/NSF; Ice Core; Holocene", "locations": "Antarctica; Antarctic Peninsula", "north": -57.8, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Truffer, Martin; Gordon, Arnold; Huber, Bruce; Mosley-Thompson, Ellen; Leventer, Amy; Vernet, Maria; Smith, Craig; Thompson, Lonnie G.", "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; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "AMGRF; MGDS; R2R; USAP-DC", "science_programs": "LARISSA", "south": -67.8, "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans", "uid": "p0000101", "west": -68.0}, {"awards": "1245703 Manahan, Donal", "bounds_geometry": "POLYGON((-68.0574 -52.7267,-67.39775 -52.7267,-66.7381 -52.7267,-66.07845 -52.7267,-65.4188 -52.7267,-64.75915 -52.7267,-64.0995 -52.7267,-63.43985 -52.7267,-62.7802 -52.7267,-62.12055 -52.7267,-61.4609 -52.7267,-61.4609 -53.95849,-61.4609 -55.19028,-61.4609 -56.42207,-61.4609 -57.65386,-61.4609 -58.88565,-61.4609 -60.11744,-61.4609 -61.34923,-61.4609 -62.58102,-61.4609 -63.81281,-61.4609 -65.0446,-62.12055 -65.0446,-62.7802 -65.0446,-63.43985 -65.0446,-64.0995 -65.0446,-64.75915 -65.0446,-65.4188 -65.0446,-66.07845 -65.0446,-66.7381 -65.0446,-67.39775 -65.0446,-68.0574 -65.0446,-68.0574 -63.81281,-68.0574 -62.58102,-68.0574 -61.34923,-68.0574 -60.11744,-68.0574 -58.88565,-68.0574 -57.65386,-68.0574 -56.42207,-68.0574 -55.19028,-68.0574 -53.95849,-68.0574 -52.7267))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001372", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1606"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "This project will support two training courses that will introduce early-career scientists from a wide range of disciplinary backgrounds to key issues in polar science, and especially to provide the opportunity to gain hands-on experience in Antarctic field activities. Antarctica is an ideal location to study a wide variety of questions in biology. However, few students and early-career scientists have the opportunity to work on-site in Antarctica unless they are directly associated with a senior scientist who has a funded Antarctic project. The project will further the NSF goal of training new generations of scientists by providing hands-on training in Antarctica during one course at Palmer Station in 2016 and another at McMurdo Station in 2018. This represents a continuation of nine previous courses at McMurdo Station which have a proven record of introducing participants to Antarctic science under realistic field conditions, providing opportunities to understand and appreciate the complexities and logistical challenges of undertaking science in Antarctica, enhancing the professional careers of the participants, and increasing international collaborations for early-career scientists. The proposed training courses will be open to Ph.D. students and post-doctoral scientists who have interests in the study of Antarctic marine organisms to help prepare them for success in developing their own independent research programs in polar regions. Long-standing and recent questions in evolution and ecology of Antarctic organisms will be examined with 1) field collections, 2) physiological experiments on whole organisms, 3) studies of isolated cells and tissues, 4) experiments on macromolecular processes (e.g., enzymes), and 5) molecular biological analyses.", "east": -61.4609, "geometry": "POINT(-64.75915 -58.88565)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V LMG; LMG1606", "locations": null, "north": -52.7267, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Manahan, Donal", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -65.0446, "title": "Collaborative Research: Biological Adaptations to Environmental Change in Antarctica - An Advanced Training Program for Early Career Scientists", "uid": "p0000392", "west": -68.0574}, {"awards": "1341712 Hallet, Bernard", "bounds_geometry": "POLYGON((160.9 -76.7,161.08 -76.7,161.26 -76.7,161.44 -76.7,161.62 -76.7,161.8 -76.7,161.98 -76.7,162.16 -76.7,162.34 -76.7,162.52 -76.7,162.7 -76.7,162.7 -76.79,162.7 -76.88,162.7 -76.97,162.7 -77.06,162.7 -77.15,162.7 -77.24,162.7 -77.33,162.7 -77.42,162.7 -77.51,162.7 -77.6,162.52 -77.6,162.34 -77.6,162.16 -77.6,161.98 -77.6,161.8 -77.6,161.62 -77.6,161.44 -77.6,161.26 -77.6,161.08 -77.6,160.9 -77.6,160.9 -77.51,160.9 -77.42,160.9 -77.33,160.9 -77.24,160.9 -77.15,160.9 -77.06,160.9 -76.97,160.9 -76.88,160.9 -76.79,160.9 -76.7))", "dataset_titles": "Long-term rock abrasion study in the Dry Valleys", "datasets": [{"dataset_uid": "601060", "doi": "10.15784/601060", "keywords": "Antarctica; Dry Valleys; Geology/Geophysics - Other; Rocks", "people": "Sletten, Ronald S.; Hallet, Bernard; Malin, Michael", "repository": "USAP-DC", "science_program": null, "title": "Long-term rock abrasion study in the Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/601060"}], "date_created": "Fri, 13 Oct 2017 00:00:00 GMT", "description": "Paragraph for Public Audiences: Many of the natural processes that modify the landscape inhabited by humans occur over very long timescales, making them difficult to observe. Exceptions include rare catastrophic events such as earthquakes, volcanic eruptions, and floods that occur on short timescales. Many significant processes that affect the land and landscape that we inhabit operate on time scales imperceptible to humans. One of these processes is wind transport of sand, with related impacts to exposed rock surfaces and man-made objects, including buildings, windshields, solar panels and wind-farm turbine blades. The goal of this project is to gain an understanding of wind erosion processes over long timescales, in the Antarctic Dry Valleys, a cold desert environment where there were no competing processes (such as rain and vegetation) that might mask the effects. The main objective is recovery of rock samples that were deployed in 1983/1984 at 11 locations in the Antarctic Dry Valleys, along with measurements on the rock samples and characterization of the sites. In the late 1980\u0027s and early 1990\u0027s some of these samples were returned and indicated more time was needed to accumulate information about the timescales and impacts of the wind erosion processes. This project will allow collection of the remaining samples from this experiment after 30 to 31 years of exposure. The field work will be carried out during the 2014/15 Austral summer. The results will allow direct measurement of the abrasion rate and hence the volumes and timescales of sand transport; this will conclude the longest direct examination of such processes ever conducted. Appropriate scaling of the results may be applied to buildings, vegetation (crops), and other aspects of human presence in sandy and windy locations, in order to better determine the impact of these processes and possible mitigation of the impacts. The project is a collaborative effort between a small business, Malin Space Science Systems (MSSS), and the University of Washington (UW). MSSS will highlight this Antarctic research on its web site, by developing thematic presentations describing our research and providing a broad range of visual materials. The public will be engaged through daily updates on a website and through links to material prepared for viewing in Google Earth. UW students will be involved in the laboratory work and in the interpretation of the results. Technical Description of Project: The goal of this project is to study the role of wind abrasion by entrained particles in the evolution of the McMurdo Dry Valleys in the Transantarctic Mountains. During the 1983 to 1984 field seasons, over 5000 rock targets were installed at five heights facing the 4 cardinal directions at 10 locations (with an additional site containing fewer targets) to study rates of physical weathering due primarily to eolian abrasion. In addition, rock cubes and cylinders were deployed at each site to examine effects of chemical weathering. The initial examination of samples returned after 1, 5, and 10 years of exposure, showed average contemporary abrasion rates consistent with those determined by cosmogenic isotope studies, but further stress that \"average\" should not be interpreted as meaning \"uniform.\" The samples will be characterized using mass measurements wtih 0.01 mg precision balances, digital microphotography to compare the evolution of their surface features and textures, SEM imaging to examine the micro textures of abraded rock surfaces, and optical microscopy of thin sections of a few samples to examine the consequences of particle impacts extending below the abraded surfaces. As much as 60-80% of the abrasion measured in samples from 1984-1994 appears to have occurred during a few brief hours in 1984. This is consistent with theoretical models that suggest abrasion scales as the 5th power of wind velocity. The field work will allow return of multiple samples after three decades of exposure, which will provide a statistical sampling (beyond what is acquired by studying a single sample), and will yield the mass loss data in light of complementary environmental and sand kinetic energy flux data from other sources (e.g. LTER meteorology stations). This study promises to improve insights into one of the principal active geomorphic process in the Dry Valleys, an important cold desert environment, and the solid empirical database will provide general constraints on eolian abrasion under natural conditions.", "east": 162.7, "geometry": "POINT(161.8 -77.15)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.7, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Hallet, Bernard; Sletten, Ronald S.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.6, "title": "Collaborative Proposal: Decades-long Experiment on Wind-Driven Rock Abrasion in the Ice-Free Valleys, Antarctica", "uid": "p0000074", "west": 160.9}, {"awards": "1341284 Swanger, Kate", "bounds_geometry": "POLYGON((161 -77.5,161.2 -77.5,161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.2 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163 -77.525,163 -77.55,163 -77.575,163 -77.6,163 -77.625,163 -77.65,163 -77.675,163 -77.7,163 -77.725,163 -77.75,162.8 -77.75,162.6 -77.75,162.4 -77.75,162.2 -77.75,162 -77.75,161.8 -77.75,161.6 -77.75,161.4 -77.75,161.2 -77.75,161 -77.75,161 -77.725,161 -77.7,161 -77.675,161 -77.65,161 -77.625,161 -77.6,161 -77.575,161 -77.55,161 -77.525,161 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 09 Oct 2017 00:00:00 GMT", "description": "Paragraph for Laypersons: This research focuses on the history of rock glaciers and buried glacial ice in the McMurdo Dry Valleys region of Antarctica. Rock glaciers are flowing mixtures of ice and sediments common throughout alpine and high-latitude regions on Earth and Mars. Despite similar appearances, rock glaciers can form under highly variable environmental and hydrological conditions. The main research questions addressed here are: 1) what environmental and climatological conditions foster long-term preservation of rock glaciers in Antarctica, 2) what role do rock glaciers play in Antarctic landscape evolution and the local water cycle, and 3) what can rock glaciers reveal about the extent and timing of previous glacial advances? The project will involve two Antarctic field seasons to image the interior of Antarctic rock glaciers using ground-penetrating radar, to gather ice cores for chemical analyses, and to gather surface sediments for dating. The Dry Valleys host the world?s southernmost terrestrial ecosystem (soil, stream and lake micro-organisms and mosses); rock glaciers and ground-ice are an important and poorly-studied source of meltwater and nutrients for these ecosystems. This research will shed light on the glacial and hydrological history of the Dry Valleys region and the general environmental conditions the foster rock glaciers, features that generally occur in warmer and/or wetter locations. The research will provide support for five graduate/undergraduate students, who will actively gather data in the field, followed by interpretation, dissemination and presentation of the data. Additionally, the researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities. A series of time-lapse images of hydrological processes, and videos of researchers in the field, will serve as a dramatic centerpiece in community and school presentations. Paragraph for Scientific Community: Rock glaciers are common in the McMurdo Dry Valleys, but are concentrated in a few isolated regions: western Taylor Valley, western Wright Valley, Pearse Valley and Bull Pass. The investigators hypothesize that the origin and age of these features varies by region: that rock glaciers in Pearse and Taylor valley originated as buried glacier ice, whereas rock glaciers in Wright Valley formed through permafrost processes, such as mobilization of ice-rich talus. To address these hypotheses, the project will: 1) develop relative and absolute chronologies for the rock glaciers through field mapping and optically stimulated luminescence dating of overlying sediments, 2) assess the origin of clean-ice cores through stable isotopic analyses, and 3) determine if present-day soil-moisture and temperature conditions are conducive to rock glacier formation/preservation. The proposed research will provide insight into the spatial and temporal distribution of buried glacier ice and melt-water-derived ground ice in the McMurdo Dry Valleys, with implications for glacial history, as well as the potential role of rock glaciers in the regional hydrologic cycle (and the role of ground-ice as a source for moisture and nutrient for local ecosystems). The project will provide general constraints on the climatic and hydrologic conditions that foster permafrost rock glaciers, features that generally occur under warmer and wetter conditions than those found in the present-day McMurdo Dry Valleys. The application of OSL and cosmogenic exposure dating is novel to rock glaciers, geomorphic features that have proven difficult to date, despite their ubiquity in Antarctica and their potential scientific importance. The research will provide support for five graduate/undergraduate students, who will participate in the field work, followed by interpretation, dissemination and presentation of the data. The researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities.", "east": 163.0, "geometry": "POINT(162 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Swanger, Kate", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.75, "title": "Origin and Climatic Significance of Rock Glaciers in the McMurdo Dry Valleys: Assessing Spatial and Temporal Variability", "uid": "p0000297", "west": 161.0}, {"awards": "1443260 Conway, Howard", "bounds_geometry": "POLYGON((159 -76.68,159.03 -76.68,159.06 -76.68,159.09 -76.68,159.12 -76.68,159.15 -76.68,159.18 -76.68,159.21 -76.68,159.24 -76.68,159.27 -76.68,159.3 -76.68,159.3 -76.697,159.3 -76.714,159.3 -76.731,159.3 -76.748,159.3 -76.765,159.3 -76.782,159.3 -76.799,159.3 -76.816,159.3 -76.833,159.3 -76.85,159.27 -76.85,159.24 -76.85,159.21 -76.85,159.18 -76.85,159.15 -76.85,159.12 -76.85,159.09 -76.85,159.06 -76.85,159.03 -76.85,159 -76.85,159 -76.833,159 -76.816,159 -76.799,159 -76.782,159 -76.765,159 -76.748,159 -76.731,159 -76.714,159 -76.697,159 -76.68))", "dataset_titles": "2015-2016 GPR Field Report for Allan Hills Shallow Ice Coring; Ground-based ice-penetrating radar profiles collected on the Allan Hills blue ice region", "datasets": [{"dataset_uid": "601005", "doi": "10.15784/601005", "keywords": "Allan Hills; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Navigation; Radar", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Ground-based ice-penetrating radar profiles collected on the Allan Hills blue ice region", "url": "https://www.usap-dc.org/view/dataset/601005"}, {"dataset_uid": "601668", "doi": "10.15784/601668", "keywords": "Allan Hills; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; GPR; Ice Core; Report", "people": "MacKay, Sean; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "2015-2016 GPR Field Report for Allan Hills Shallow Ice Coring", "url": "https://www.usap-dc.org/view/dataset/601668"}], "date_created": "Tue, 02 May 2017 00:00:00 GMT", "description": "Marine paleoclimate archives show that approximately one million years ago Earth\u0027s climate transitioned from 40,000-year glacial /interglacial cycles to 100,000-year cycles. This award will support a study designed to map the distribution of one million year-old ice in the Allan Hills Blue Ice Area, Antarctica using state-of-the-art ground penetrating radar. The Allen Hills was demonstrated to contain a continuous record of the past 400,000 years and is also the collection location of the oldest ice samples (990,000 years) yet recovered. The maps resulting from this study will be used to select an ice-core drilling site at which a million-plus year-old continuous record of climate could be recovered. Ice cores contain the only kind of record to directly capture atmospheric gases and aerosols, but no ice-core-based climate record yet extends continuously beyond the past 800,000 years. A million-plus year-old record will allow better understanding of the major mechanisms and driving forces of natural climate variability in a world with 100,000-year glacial/interglacial cycles. The project will support two early career scientists in collaboration with senior scientists, as well as a graduate student, and will conduct outreach to schools and the public. The Allan Hills Blue Ice Area preserves a continuous climate record covering the last 400,000 years along an established glaciological flow line. Two kilometers to the east of this flow line, the oldest ice on Earth (~1 million years old) is found only 120 m below the surface. Meteorites collected in the area are reported to be as old as 1.8 million years, suggesting still older ice may be present. Combined, these data strongly suggest that the Allen Hills area could contain a continuous, well-resolved environmental record, spanning at least the last million years. As such, this area has been selected as an upcoming target for the new Intermediate Depth Ice Core Drill by the US Ice Core Working Group. This drill will recover a higher-quality core than previous dry drilling attempts. This project will conduct a comprehensive ground penetrating radar survey aimed at tracing the signature of the million-year-old ice layer throughout the region. The resulting map will be used to select a drill site from which an ice core containing the million-plus year-old continuous climate record will be collected. The proposed activities are a necessary precursor to the collection of the oldest known ice on Earth. Ice cores provide a robust reconstruction of past climate and extending this record beyond the 800,000 years currently available will open new opportunities to study the climate system. The data collected will also be used to investigate the bedrock and ice flow parameters favorable to the preservation of old ice, which may allow targeted investigation of other blue ice areas in Antarctica.", "east": 159.3, "geometry": "POINT(159.15 -76.765)", "instruments": null, "is_usap_dc": true, "keywords": "Allan Hills; FIELD SURVEYS; ICE SHEETS", "locations": "Allan Hills", "north": -76.68, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.85, "title": "Collaborative Research: Allan HILLs Englacial Site (AHILLES) Selection", "uid": "p0000385", "west": 159.0}, {"awards": "0944671 Wiens, Douglas; 0944794 Winberry, J. Paul", "bounds_geometry": "POLYGON((-163 -83.7,-161.9 -83.7,-160.8 -83.7,-159.7 -83.7,-158.6 -83.7,-157.5 -83.7,-156.4 -83.7,-155.3 -83.7,-154.2 -83.7,-153.1 -83.7,-152 -83.7,-152 -83.8,-152 -83.9,-152 -84,-152 -84.1,-152 -84.2,-152 -84.3,-152 -84.4,-152 -84.5,-152 -84.6,-152 -84.7,-153.1 -84.7,-154.2 -84.7,-155.3 -84.7,-156.4 -84.7,-157.5 -84.7,-158.6 -84.7,-159.7 -84.7,-160.8 -84.7,-161.9 -84.7,-163 -84.7,-163 -84.6,-163 -84.5,-163 -84.4,-163 -84.3,-163 -84.2,-163 -84.1,-163 -84,-163 -83.9,-163 -83.8,-163 -83.7))", "dataset_titles": "Geophysical Study of Ice Stream Stick Slip; Whillans Ice Stream Stick-slip", "datasets": [{"dataset_uid": "000169", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Geophysical Study of Ice Stream Stick Slip", "url": "http://ds.iris.edu/mda/2C/?timewindow=2010-2011"}, {"dataset_uid": "609632", "doi": "10.7265/N5PC309V", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Whillans Ice Stream", "people": "Anandakrishnan, Sridhar; Winberry, Paul; Wiens, Douglas; Alley, Richard", "repository": "USAP-DC", "science_program": null, "title": "Whillans Ice Stream Stick-slip", "url": "https://www.usap-dc.org/view/dataset/609632"}], "date_created": "Wed, 16 Nov 2016 00:00:00 GMT", "description": "This award supports a three-year study of the ongoing deceleration and stick-slip motion of Whillans Ice Stream (WIS), West Antarctica. Understanding the dynamic behavior of ice streams is essential for predicting the future of the West Antarctic Ice Sheet (WAIS). Despite being one of the best-studied ice streams in Antarctica, the surprising flow characteristics of WIS continue to demand interdisciplinary research. Recent estimates indicate that the WIS may stagnate within 50 years, resulting in a significant change to the mass balance of the Siple Coast sector of West Antarctica. The reasons for the ongoing stagnation are not well known, and are possibly linked (causally or coincidentally) to the stick-slip behavior. Our recent work on WIS stick-slip motion suggest that all slip events nucleate from a common location on the ice stream, suggesting that a relatively small (approximately 10 km in diameter) region of the exerts fundamental control over the flow of this large ice stream (100s of km long and 100 kilometers wide). We hypothesize that this is a region of increased bed strength and our measurements will address that hypothesis. We will deploy a series of GPS receivers and seismometers on the ice stream to accurately locate the nucleation region so that a comprehensive ground based geophysical survey can be conducted to determine the physical properties of bed at the nucleation point. The ground geophysical program will consist of reflection seismic and ice-penetrating radar studies that will better constrain the properties of both the hypothesized higher-friction nucleation zone and the surrounding regions. Slip events also generate seismic energy that can be recorded 100s of km away from the ice stream, thus, the GPS and seismometer deployment will also aid us in relating seismic waveforms directly with the rapid motion that occurs during slip events. The increased ability to relate rupture processes with seismic emissions will allow us to use archived seismic records to explore changes in the behavior of WIS during the later half of the 20th century. Broader impacts of this study include improved knowledge ice sheet dynamics, which remain a poorly constrained component of the climate system, thus, limiting our ability to predict the Earth\u0027s response to climate change. The scientific work includes the education of two graduate students and continued training of one post-doctoral scholar, thus helping to train the next generation of polar scientists. We will expose the broader public to polar science through interactions with the media and by take advantaging of programs to include K-12 educators in our field work.", "east": -152.0, "geometry": "POINT(-157.5 -84.2)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOGRAPHS", "is_usap_dc": true, "keywords": "West Antarctic Ice Sheet; Geodesy; GROUND-BASED OBSERVATIONS; Not provided; Seismic; Geodetic Gps Data", "locations": "West Antarctic Ice Sheet", "north": -83.7, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Winberry, Paul; Anandakrishnan, Sridhar; Alley, Richard; Wiens, Douglas", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided", "repo": "IRIS", "repositories": "IRIS; USAP-DC", "science_programs": null, "south": -84.7, "title": "Collaborative Research: Geophysical Study of Ice Stream Stick-slip Dynamics", "uid": "p0000053", "west": -163.0}, {"awards": "1141326 Rotella, Jay", "bounds_geometry": "POLYGON((163.1 -70.3,163.59 -70.3,164.08 -70.3,164.57 -70.3,165.06 -70.3,165.55 -70.3,166.04 -70.3,166.53 -70.3,167.02 -70.3,167.51 -70.3,168 -70.3,168 -70.98,168 -71.66,168 -72.34,168 -73.02,168 -73.7,168 -74.38,168 -75.06,168 -75.74,168 -76.42,168 -77.1,167.51 -77.1,167.02 -77.1,166.53 -77.1,166.04 -77.1,165.55 -77.1,165.06 -77.1,164.57 -77.1,164.08 -77.1,163.59 -77.1,163.1 -77.1,163.1 -76.42,163.1 -75.74,163.1 -75.06,163.1 -74.38,163.1 -73.7,163.1 -73.02,163.1 -72.34,163.1 -71.66,163.1 -70.98,163.1 -70.3))", "dataset_titles": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2017 Antarctic field season", "datasets": [{"dataset_uid": "601125", "doi": "10.15784/601125", "keywords": "Antarctica; Biota; Sea Ice", "people": "Rotella, Jay", "repository": "USAP-DC", "science_program": null, "title": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2017 Antarctic field season", "url": "https://www.usap-dc.org/view/dataset/601125"}], "date_created": "Mon, 08 Feb 2016 00:00:00 GMT", "description": "Abstract The Erebus Bay population of Weddell seals in Antarctica?s Ross Sea is the most southerly breeding population of mammal in the world, closely associated with persistent shore-fast ice, and one that has been intensively studied since 1968. The resulting long-term database, which includes data for 20,586 marked individuals, contains detailed population information that provides an excellent opportunity to study linkages between environmental conditions and demographic processes in the Antarctic. The population?s location is of special interest as the Ross Sea is one of the most productive areas of the Southern Ocean, one of the few pristine marine environments remaining on the planet, and, in contrast to the Antarctic Peninsula and Arctic, is undergoing a gradual lengthening of the sea-ice season. The work to be continued here capitalizes on (1) long-term data for individual seals and their polar environment; (2) experience collecting and analyzing data from the extensive study population; and (3) recent statistical advances in hierarchical modeling that allow for rigorous treatment of individual heterogeneity (in mark-recapture and body mass data) and inclusion of diverse covariates hypothesized to explain variation in fitness components. Covariates to be considered include traits of individuals and their mothers and environmental conditions throughout life. The study will continue to (1) provide detailed data on known-age individuals to other science projects and (2) educate and mentor the next generation of ecologists through academic and professional training and research experiences.", "east": 168.0, "geometry": "POINT(165.55 -73.7)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -70.3, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rotella, Jay; Garrott, Robert", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.1, "title": "The Demographic Consequences of Environmental Variability and Individual Heterogeneity in Life-history Tactics of a Long-lived Antarctic Marine Predator", "uid": "p0000299", "west": 163.1}, {"awards": "0944141 Ballard, Grant; 0944358 Dugger, Katie; 0944411 Ainley, David", "bounds_geometry": "POLYGON((165.9 -76.9,166.25 -76.9,166.6 -76.9,166.95 -76.9,167.3 -76.9,167.65 -76.9,168 -76.9,168.35 -76.9,168.7 -76.9,169.05 -76.9,169.4 -76.9,169.4 -76.97,169.4 -77.04,169.4 -77.11,169.4 -77.18,169.4 -77.25,169.4 -77.32,169.4 -77.39,169.4 -77.46,169.4 -77.53,169.4 -77.6,169.05 -77.6,168.7 -77.6,168.35 -77.6,168 -77.6,167.65 -77.6,167.3 -77.6,166.95 -77.6,166.6 -77.6,166.25 -77.6,165.9 -77.6,165.9 -77.53,165.9 -77.46,165.9 -77.39,165.9 -77.32,165.9 -77.25,165.9 -77.18,165.9 -77.11,165.9 -77.04,165.9 -76.97,165.9 -76.9))", "dataset_titles": "Adelie penguin banding data 1994-2009; Adelie penguin chick counts 1997-2009; Adelie penguin chick measurements 1996 - 2009; Adelie penguin diet data 1996 - 2009; Adelie penguin dive data 1999-2009; Adelie penguin Geolocation Sensor data 2003-2007; Adelie penguin resighting data 1997-2009; Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science; Adelie penguin satellite position data 2000-2009; Adelie penguin weighbridge data 1994-2009; Daily weather observations 1996-2009; Leopard Seal counts 1997-2009; PRBO/California Avian Data Center (CADC)", "datasets": [{"dataset_uid": "600005", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin banding data 1994-2009", "url": "https://www.usap-dc.org/view/dataset/600005"}, {"dataset_uid": "600007", "doi": "", "keywords": "Biota", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin chick counts 1997-2009", "url": "https://www.usap-dc.org/view/dataset/600007"}, {"dataset_uid": "601444", "doi": "10.15784/601444", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Mark-Recapture; Monitoring; Penguin; Ross Island", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601444"}, {"dataset_uid": "600015", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Daily weather observations 1996-2009", "url": "https://www.usap-dc.org/view/dataset/600015"}, {"dataset_uid": "600006", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin chick measurements 1996 - 2009", "url": "https://www.usap-dc.org/view/dataset/600006"}, {"dataset_uid": "600014", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin weighbridge data 1994-2009", "url": "https://www.usap-dc.org/view/dataset/600014"}, {"dataset_uid": "600013", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin dive data 1999-2009", "url": "https://www.usap-dc.org/view/dataset/600013"}, {"dataset_uid": "600008", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin diet data 1996 - 2009", "url": "https://www.usap-dc.org/view/dataset/600008"}, {"dataset_uid": "600012", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin satellite position data 2000-2009", "url": "https://www.usap-dc.org/view/dataset/600012"}, {"dataset_uid": "600011", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin resighting data 1997-2009", "url": "https://www.usap-dc.org/view/dataset/600011"}, {"dataset_uid": "600010", "doi": "", "keywords": "Biota; Oceans", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Leopard Seal counts 1997-2009", "url": "https://www.usap-dc.org/view/dataset/600010"}, {"dataset_uid": "600009", "doi": "", "keywords": null, "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin Geolocation Sensor data 2003-2007", "url": "https://www.usap-dc.org/view/dataset/600009"}, {"dataset_uid": "000154", "doi": "", "keywords": null, "people": null, "repository": "CADC", "science_program": null, "title": "PRBO/California Avian Data Center (CADC)", "url": "http://data.prbo.org/apps/penguinscience/"}], "date_created": "Sun, 13 Dec 2015 00:00:00 GMT", "description": "While changes in populations typically are tracked to gauge the impact of climate or habitat change, the process involves the response of individuals as each copes with an altered environment. In a study of Adelie penguins that spans 13 breeding seasons, results indicate that only 20% of individuals within a colony successfully raise offspring, and that they do so because of their exemplary foraging proficiency. Moreover, foraging appears to require more effort at the largest colony, where intraspecific competition is higher than at small colonies, and also requires more proficiency during periods of environmental stress. When conditions are particularly daunting, emigration dramatically increases, countering the long-standing assumption that Ad\u00e9lie penguins are highly philopatric. The research project will 1) determine the effect of age, experience and physiology on individual foraging efficiency; 2) determine the effect of age, experience, and individual quality on breeding success and survival in varying environmental and competitive conditions at the colony level; and 3) develop a comprehensive model for the Ross-Beaufort Island metapopulation dynamics. Broader impacts include training of interns, continuation of public outreach through the highly successful project website penguinscience.com, development of classroom materials and other standards-based instructional resources.", "east": 169.4, "geometry": "POINT(167.65 -77.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.9, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ainley, David; Dugger, Katie; Ballard, Grant", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "CADC; USAP-DC", "science_programs": null, "south": -77.6, "title": "COLLABORATIVE: Adelie Penguin Response to Climate Change at the Individual, Colony and Metapopulation Levels", "uid": "p0000318", "west": 165.9}, {"awards": "1043454 Kooyman, Gerald", "bounds_geometry": "POLYGON((-172.642 -72.55,-170.9074 -72.55,-169.1728 -72.55,-167.4382 -72.55,-165.7036 -72.55,-163.969 -72.55,-162.2344 -72.55,-160.4998 -72.55,-158.7652 -72.55,-157.0306 -72.55,-155.296 -72.55,-155.296 -73.0743,-155.296 -73.5986,-155.296 -74.1229,-155.296 -74.6472,-155.296 -75.1715,-155.296 -75.6958,-155.296 -76.2201,-155.296 -76.7444,-155.296 -77.2687,-155.296 -77.793,-157.0306 -77.793,-158.7652 -77.793,-160.4998 -77.793,-162.2344 -77.793,-163.969 -77.793,-165.7036 -77.793,-167.4382 -77.793,-169.1728 -77.793,-170.9074 -77.793,-172.642 -77.793,-172.642 -77.2687,-172.642 -76.7444,-172.642 -76.2201,-172.642 -75.6958,-172.642 -75.1715,-172.642 -74.6472,-172.642 -74.1229,-172.642 -73.5986,-172.642 -73.0743,-172.642 -72.55))", "dataset_titles": "NBP1302 data; Pre and Post Molt Biology of Emperor Penguins - Oden Trans - Ross / Amundsen Sea Cruise", "datasets": [{"dataset_uid": "000179", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1302 data", "url": "https://www.rvdata.us/search/cruise/NBP1302"}, {"dataset_uid": "600149", "doi": "10.15784/600149", "keywords": "Amundsen Sea; Biota; Oceans; Penguin; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Kooyman, Gerald", "repository": "USAP-DC", "science_program": null, "title": "Pre and Post Molt Biology of Emperor Penguins - Oden Trans - Ross / Amundsen Sea Cruise", "url": "https://www.usap-dc.org/view/dataset/600149"}], "date_created": "Sat, 12 Dec 2015 00:00:00 GMT", "description": "The emperor penguin dives deeper and longer, fasts longer, and endures the harshest weather conditions of all diving birds. It spends about four and half months per annum deep in Antarctic pack ice away from shore and stations, and thus is largely unavailable for study. This time includes preparation for the molt, and travel to the colony to breed, a time period in which great swings in body weight occur. This study will fill an important gap in what we know about the biology of the annual cycle of the emperor by examining the molt-post molt period. The P.I. proposes to traverse the Amundsen and Bellingshausen seas on the Oden, to locate and tag emperor penguins during the molt season. The objectives are to (1) Place satellite tags on 20 adult post molt birds to determine their route, rate of travel, and diving behavior as they return back to their breeding colonies, (2) Obtain an index of body condition, (3) Collect guano to determine the type of food consumed by emperor penguins in the region, (4) Conduct shipboard surveys to sight and plot the location and abundance of adult and juvenile birds on the ship\u0027s track. The PI hypothesizes that bird dives will be shallow during the initial post-molt phase, and that food will consist primarily of krill; that there will be differential dispersal of birds from the Ross Sea vs. Marie Byrd Land, with Ross Sea birds traveling farther; and that the greatest adult mortality occurs during the molt and early post molt period. Broader impacts include training of a post doc, a graduate student, and an aquarium volunteer. The P.I. also will present findings through a website, through public lectures, and in collaboration with the Birch aquarium.", "east": -155.296, "geometry": "POINT(-163.969 -75.1715)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "R/V NBP; Not provided", "locations": null, "north": -72.55, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kooyman, Gerald", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -77.793, "title": "Pre and post molt biology of emperor penguins - Oden trans - Ross / Amundsen Sea cruise", "uid": "p0000325", "west": -172.642}, {"awards": "1142156 Marschall, Horst", "bounds_geometry": "POLYGON((-6.44 -71.93,-5.378 -71.93,-4.316 -71.93,-3.254 -71.93,-2.192 -71.93,-1.13 -71.93,-0.068 -71.93,0.994 -71.93,2.056 -71.93,3.118 -71.93,4.18 -71.93,4.18 -71.998,4.18 -72.066,4.18 -72.134,4.18 -72.202,4.18 -72.27,4.18 -72.338,4.18 -72.406,4.18 -72.474,4.18 -72.542,4.18 -72.61,3.118 -72.61,2.056 -72.61,0.994 -72.61,-0.068 -72.61,-1.13 -72.61,-2.192 -72.61,-3.254 -72.61,-4.316 -72.61,-5.378 -72.61,-6.44 -72.61,-6.44 -72.542,-6.44 -72.474,-6.44 -72.406,-6.44 -72.338,-6.44 -72.27,-6.44 -72.202,-6.44 -72.134,-6.44 -72.066,-6.44 -71.998,-6.44 -71.93))", "dataset_titles": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antarctica", "datasets": [{"dataset_uid": "600135", "doi": "10.15784/600135", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Dronning Maud Land; Geochemistry; Geochronology; Solid Earth", "people": "Marschall, Horst", "repository": "USAP-DC", "science_program": null, "title": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antarctica", "url": "https://www.usap-dc.org/view/dataset/600135"}], "date_created": "Fri, 23 Oct 2015 00:00:00 GMT", "description": "Geochemical studies of single mineral grains in rocks can be probed to reconstruct the history of our planet. The mineral zircon (ZrSiO4) is of unique importance in that respect because of its reliability as a geologic clock due to its strong persistence against weathering, transport and changes in temperature and pressure. Uranium-Lead (U-Pb) dating of zircon grains is, perhaps, the most frequently employed method of extracting time information on geologic processes that shaped the continental crust, and has been used to constrain the evolution of continents and mountain belts through time. In addition, the isotopic composition of the element Hafnium (Hf) in zircon is used to date when the continental crust was generated by extraction of magma from the underlying mantle. Melting of rocks in the mantle and deep in the continental crust are key processes in the evolution of the continents, and they are recorded in the Hf isotopic signatures of zircon. Although the analytical procedures for U-Pb dating and Hf isotope analyses of zircon are robust now, our understanding of zircon growth and its exchange of elements and isotopes with its surrounding rock or magma are still underdeveloped. The focus of the proposed study, therefore, is to unravel the evolution of zircon Hf isotopes in rocks that were formed deep in the Earth?s crust, and more specifically, to apply these isotopic methods to rocks collected in Dronning Maud Land (DML), East Antarctica. Dronning Maud Land (DML) occupied a central location during the formation of supercontinents ? large landmasses made up of all the continents that exist today - more than 500 million years ago. It is currently thought that supercontinents were formed and dismembered five or six times throughout Earth?s history. The area of DML is key for understanding the formation history of the last two supercontinents. The boundaries of continents that were merged to form those supercontinents are most likely hidden in DML. In this study, the isotopic composition of zircon grains recovered from DML rocks will be employed to identify these boundaries across an extensive section through the area. The rock samples were collected by the investigator during a two-month expedition to Antarctica in the austral summer of 2007?2008. The results of dating and isotope analyses of zircon of the different DML crustal domains will deliver significant insight into the regional geology of East Antarctica and its previous northern extension into Africa. This has significance for the reconstruction of the supercontinents and defining the continental boundaries in DML.", "east": 4.18, "geometry": "POINT(-1.13 -72.27)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -71.93, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Marschall, Horst", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.61, "title": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antacrtica", "uid": "p0000448", "west": -6.44}, {"awards": "1043657 Cassano, John", "bounds_geometry": "POLYGON((163 -74.5,163.9 -74.5,164.8 -74.5,165.7 -74.5,166.6 -74.5,167.5 -74.5,168.4 -74.5,169.3 -74.5,170.2 -74.5,171.1 -74.5,172 -74.5,172 -74.9,172 -75.3,172 -75.7,172 -76.1,172 -76.5,172 -76.9,172 -77.3,172 -77.7,172 -78.1,172 -78.5,171.1 -78.5,170.2 -78.5,169.3 -78.5,168.4 -78.5,167.5 -78.5,166.6 -78.5,165.7 -78.5,164.8 -78.5,163.9 -78.5,163 -78.5,163 -78.1,163 -77.7,163 -77.3,163 -76.9,163 -76.5,163 -76.1,163 -75.7,163 -75.3,163 -74.9,163 -74.5))", "dataset_titles": "Ocean-Ice-Atmosphere Interactions in the Terra Nova Bay Polynya, Antarctica", "datasets": [{"dataset_uid": "600125", "doi": "10.15784/600125", "keywords": "Antarctica; Atmosphere; Meteorology; Navigation; Oceans; Southern Ocean; Unmanned Aircraft", "people": "Cassano, John; Palo, Scott", "repository": "USAP-DC", "science_program": null, "title": "Ocean-Ice-Atmosphere Interactions in the Terra Nova Bay Polynya, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600125"}], "date_created": "Thu, 22 Oct 2015 00:00:00 GMT", "description": "Antarctic coastal polynas are, at the same time, sea-ice free sites and \u0027sea-ice factories\u0027. They are open water surface locations where water mass transformation and densification occurs, and where atmospheric exchanges with the deep ocean circulation are established. Various models of the formation and persistence of these productive and diverse ocean ecosystems are hampered by the relative lack of in situ meteorological and physical oceanographic observations, especially during the inhospitable conditions of their formation and activity during the polar night. Characterization of the lower atmosphere properties, air-sea surface heat fluxes and corresponding ocean hydrographic profiles of Antarctic polynyas, especially during strong wind events, is sought for a more detailed understanding of the role of polynyas in the production of latent-heat type sea ice and the formation, through sea ice brine rejection, of dense ocean bottom waters A key technological innovation in this work continues to be the use of instrumented unmanned aircraft systems (UAS), to enable the persistent and safe observation of the interaction of light and strong katabatic wind fields, and mesocale cyclones in the Terra Nova Bay (Victoria Land, Antarctica) polynya waters during late winter and early summer time frames.", "east": 172.0, "geometry": "POINT(167.5 -76.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -74.5, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Cassano, John; Palo, Scott", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.5, "title": "Collaborative Research: Ocean-Ice-Atmosphere Interactions in the Terra Nova Bay Polynya, Antarctica", "uid": "p0000417", "west": 163.0}, {"awards": "1043217 Zagorodnov, Victor", "bounds_geometry": null, "dataset_titles": "Fiber-Optic Distributed Temperature Sensing at Windless Bight", "datasets": [{"dataset_uid": "609604", "doi": "10.7265/N5V122QS", "keywords": "Antarctica; Ice Shelf; McMurdo Sound; Mooring; Oceans; Physical Oceanography; Ross Ice Shelf; Southern Ocean", "people": "Holland, David; Zagorodnov, Victor; Tyler, Scott W.", "repository": "USAP-DC", "science_program": null, "title": "Fiber-Optic Distributed Temperature Sensing at Windless Bight", "url": "https://www.usap-dc.org/view/dataset/609604"}], "date_created": "Tue, 05 May 2015 00:00:00 GMT", "description": "Abstract Researchers will explore the use of a distributed temperature sensing monitoring system (DTS), using fiber-optical (FO) technology, as the basis of a sustainable, sub-ice cavity sensing array. FO cable systems, such as may be deployed through a hot-water drilled hole through an ice shelf, passing through the underlying cavity to the sea floor, are capable of measuring temperatures down fiber at 1 meter intervals, and at time frequencies as high as 15 seconds. DTS FO systems operate via optical time domain reflectometry along the fiber waveguide using inelastic backscatter of coherent laser light as a probe beam in the FO environment. The introduction of new technologies to the harsh environmental conditions of the Antarctic are often associated with high risk. However, the potential rewards of this approach (e.g. multiyear capability, minimal submerged mechanical or electrical components that may fail, relative simplicity of deployment and measurement principle, yet yielding distributed real time and spatial observation) are attractive enough to conduct a pilot project at a field-ready location (McMurdo). Current indications are that the instability of some of the world\u0027s largest ice sheets located around the Antarctic and Greenland may be caused by the presence of warming, deep ocean waters, shoaling over continental shelves, and melting the underside of floating ice shelves. Additional knowledge of the temporal and spatial variability of the temperature fields underneath terminal ice shelves, such as those draining the West Antarctic Ice Sheet, are needed to accurately project future global climate effects on ice-shelf ocean interactions, and in order to inform societal and technological aspects of adaption to changing sea-level.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e TEMPERATURE LOGGERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS", "is_usap_dc": true, "keywords": "GROUND STATIONS; Not provided; Conservative Temperature; MOORINGS; Ice Shelf Temperature; Ocean Temperature", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Zagorodnov, Victor; Holland, David; Tyler, Scott W.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED \u003e MOORINGS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Application of Distributed Temperature Sensors (DTS) for Antarctic Ice Shelves and Cavities", "uid": "p0000183", "west": null}, {"awards": "0229314 Stone, John", "bounds_geometry": null, "dataset_titles": "Reedy Glacier Exposure Ages, Antarctica", "datasets": [{"dataset_uid": "609601", "doi": "10.7265/N5MG7MF1", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Cosmogenic; Geochemistry; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Reedy Glacier; Sample/collection Description; Sample/Collection Description", "people": "Stone, John", "repository": "USAP-DC", "science_program": null, "title": "Reedy Glacier Exposure Ages, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609601"}], "date_created": "Mon, 30 Mar 2015 00:00:00 GMT", "description": "The stability of the marine West Antarctic Ice Sheet (WAIS) remains an important, unresolved problem for predicting future sea level change. Recent studies indicate that the mass balance of the ice sheet today may be negative or positive. The apparent differences may stem in part from short-term fluctuations in flow. By comparison, geologic observations provide evidence of behavior over much longer time scales. Recent work involving glacial-geologic mapping, dating and ice-penetrating radar surveys suggests that deglaciation of both the Ross Sea Embayment and coastal Marie Byrd Land continued into the late Holocene, and leaves open the possibility of ongoing deglaciation and grounding-line retreat. However, previous work in the Ross Sea Embayment was based on data from just three locations that are all far to the north of the present grounding line. Additional data from farther south in the Ross Sea Embayment are needed to investigate whether recession has ended, or if the rate and pattern of deglaciation inferred from our previous study still apply to the present grounding line. This award provides support to reconstruct the evolution of Reedy Glacier, in the southern Transantarctic Mountains, since the Last Glacial Maximum (LGM). Because Reedy Glacier emerges from the mountains above the grounding line, its surface slope and elevation should record changes in thickness of grounded ice in the Ross Sea up to the present day. The deglaciation chronology of Reedy Glacier therefore can indicate whether Holocene retreat of the WAIS ended thousands of years ago, or is still continuing at present. This integrated glaciologic, glacial-geologic, and cosmogenic-isotope exposure- dating project will reconstruct past levels of Reedy Glacier. Over two field seasons, moraines will be mapped, dated and correlated at sites along the length of the glacier. Radar and GPS measurements will be made to supplement existing ice thickness and velocity data, which are needed as input for a model of glacier dynamics. The model will be used to relate geologic measurements to the grounding-line position downstream. Ultimately, the mapping, dating and ice-modeling components of the study will be integrated into a reconstruction that defines changes in ice thickness in the southern Ross Sea since the LGM, and relates these changes to the history of grounding-line retreat. This work directly addresses key goals of the West Antarctic Ice Sheet Initiative, which are to understand the dynamics, recent history and possible future behavior of the West Antarctic Ice Sheet.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "Surface Exposure Dates; FIELD SURVEYS; Aluminum-26; Erosion; Rock Samples; Beryllium-10; Exposure Age", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Stone, John", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Late Quaternary History of Reedy Glacier", "uid": "p0000029", "west": null}, {"awards": "0632136 Nyblade, Andrew; 0632322 Wilson, Terry", "bounds_geometry": "POLYGON((-20 -70,-1 -70,18 -70,37 -70,56 -70,75 -70,94 -70,113 -70,132 -70,151 -70,170 -70,170 -72,170 -74,170 -76,170 -78,170 -80,170 -82,170 -84,170 -86,170 -88,170 -90,151 -90,132 -90,113 -90,94 -90,75 -90,56 -90,37 -90,18 -90,-1 -90,-20 -90,-20 -88,-20 -86,-20 -84,-20 -82,-20 -80,-20 -78,-20 -76,-20 -74,-20 -72,-20 -70))", "dataset_titles": "Incorporated Research Institutions for Seismology (IRIS); University NAVSTAR Consortium (UNAVCO)", "datasets": [{"dataset_uid": "000132", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Incorporated Research Institutions for Seismology (IRIS)", "url": "http://www.iris.edu/mda/YT?timewindow=2007-2018"}, {"dataset_uid": "000131", "doi": "", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "University NAVSTAR Consortium (UNAVCO)", "url": "http://www.unavco.org/data/gps-gnss/data-access-methods/dai2/app/dai2.html#groupingMod=contains;grouping=POLENET%20-%20ANET;scope=Station;sampleRate=normal"}], "date_created": "Thu, 22 Jan 2015 00:00:00 GMT", "description": "This project constructs POLENET a network of GPS and seismic stations in West Antarctica to understand how the mass of the West Antarctic ice sheet (WAIS) changes with time. The information is ultimately used to predict sea level rise accompanying global warming and interpret climate change records. The GPS (global positioning system) stations measure vertical and horizontal movements of bedrock, while the seismic stations characterize physical properties of the ice/rock interface, lithosphere, and mantle. Combined with satellite data, this project offers a more complete picture of the ice sheet\u0027s current state, its likely change in the near future, and its overall size during the last glacial maximum. This data will also be used to infer sub-ice sheet geology and the terrestrial heat flux, critical inputs to models of glacier movement. As well, this project improves tomographic models of the earth\u0027s deep interior and core through its location in the Earth\u0027s poorly instrumented southern hemisphere. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eBroader impacts of this project are varied. The work is relevant to society for improving our understanding of the impacts of global warming on sea level rise. It also supports education at the postdoctoral, graduate, and undergraduate levels, and outreach to groups underrepresented in the sciences. As an International Polar Year contribution, this project establishes a legacy of infrastructure for polar measurements. It also involves an international collaboration of twenty four countries. For more information see IPY Project #185 at IPY.org. NSF is supporting a complementary Arctic POLENET array being constructed in Greenland under NSF Award #0632320.", "east": 170.0, "geometry": "POINT(75 -80)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "Antarctica; Bedrock; Ice/Rock Interface; Climate Change; Seismic; West Antarctic Ice Sheet; FIELD SURVEYS; LABORATORY; Not provided; FIELD INVESTIGATION; Mass Balance; COMPUTERS; Sub-Ice Sheet Geology; Sea Level; Terrestrial Heat Flux", "locations": "Antarctica; West Antarctic Ice Sheet", "north": -70.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Wilson, Terry; Bevis, Michael; Anandakrishnan, Sridhar; Wiens, Douglas; Aster, Richard; Smalley, Robert; Nyblade, Andrew; Winberry, Paul; Hothem, Larry; Dalziel, Ian W.; Huerta, Audrey D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "IRIS", "repositories": "IRIS; UNAVCO", "science_programs": null, "south": -90.0, "title": "Collaborative Research: IPY: POLENET-Antarctica: Investigating Links Between Geodynamics and Ice Sheets", "uid": "p0000315", "west": -20.0}, {"awards": "1441432 Scambos, Ted", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 30 Dec 2014 00:00:00 GMT", "description": "The investigators propose to build and test a multi-sensor, automated measurement station for monitoring Arctic and Antarctic ice-ocean environments. The system, based on a previously successful design, will incorporate weather and climate sensors, camera, snow and firn sensors, instruments to measure ice motion, ice and ocean thermal profilers, hydrophone, and salinity sensors. This new system will have two-way communications for real-time data delivery and is designed for rapid deployment by a small field group. AMIGOS-II will be capable of providing real time information on geophysical processes such as weather, snowmelt, ice motion and strain, fractures and melt ponds, firn thermal profiling, and ocean conditions from multiple levels every few hours for 2-4 years. Project personnel will conduct a field test of the new system at a location with a deep ice-covered lake. Development of AMIGOS-II is motivated by recent calls by the U.S. Antarctic Program Blue-Ribbon Panel to increase Antarctic logistical effectiveness, which cites a need for greater efficiency in logistical operations. Installation of autonomous stations with reduced logistical requirements advances this goal.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; IN SITU/LABORATORY INSTRUMENTS \u003e CURRENT/WIND METERS \u003e CURRENT METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e TEMPERATURE PROFILERS", "is_usap_dc": false, "keywords": "Ice Ocean Interface; FIELD SURVEYS; Climate; Firn Temperature Measurements; Snowmelt; Strain; Ice Movement; Melt Ponds; LABORATORY; Not provided; Multi-Sensor; FIELD INVESTIGATION", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Instrumentation and Support", "paleo_time": null, "persons": "Scambos, Ted", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "A Low-power, Quick-install Polar Observation System (\u0027AMIGOS-II\u0027) for Monitoring Climate-ice-ocean Interactions", "uid": "p0000443", "west": null}, {"awards": "0087345 Conway, Howard", "bounds_geometry": "POINT(112 79)", "dataset_titles": null, "datasets": null, "date_created": "Fri, 15 Aug 2014 00:00:00 GMT", "description": "This award supports a program of ground-based geophysical measurements to map in detail the spatial variations of ice flow, accumulation rate, internal layering and ice thickness at the sites which have been identified as promising locations to drill the next deep ice core in West Antarctica. The main investigative tools are a high- and low-frequency ice penetrating radar to image the topography of internal layers and the bed, repeat GPS surveys to calculate the present day surface velocity field, synthetic aperture radar (SAR) interferometry to calculate the regional velocity field, and short firn cores to calculate present day accumulation rates. The data which will be collected will be used to as input to time-dependent ice flow and temperature models that will predict depth variation of age, layer thickness, and temperature. As well as yielding an estimate of expected conditions before drilling, the mismatch between the model prediction and data eventually recovered from the core will help infer thinning and climate (accumulation and temperature) histories for the region. The Western Divide, between the Ross Sea Embayment and the Amundsen Sea, has been identified as the region which best satisfies the criteria which have been established for a deep drilling site. Preliminary site selection using airborne geophysical methods has identified several potential drill sites on the Western Divide where the climate record should be best preserved. This work will contribute in a major way to the final site selection for the next deep ice core in West Antarctica.", "east": -112.0, "geometry": "POINT(-112 -79)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e SAR", "is_usap_dc": false, "keywords": "FIELD SURVEYS; Internal Layering; Radar; Accumulation Rate; FIELD INVESTIGATION; LABORATORY; Not provided; Internal Layers; Antarctica; Ice Flow; Interferometry; Ice Thickness", "locations": "Antarctica", "north": -79.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard; Waddington, Edwin D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -79.0, "title": "Collaborative Research: Western Divide West Antarctic Ice Cores (WAISCORES) Site Selection", "uid": "p0000557", "west": -112.0}, {"awards": "1043265 Deming, Jody", "bounds_geometry": "POLYGON((162.1397 -77.14085,162.828507 -77.14085,163.517314 -77.14085,164.206121 -77.14085,164.894928 -77.14085,165.583735 -77.14085,166.272542 -77.14085,166.961349 -77.14085,167.650156 -77.14085,168.338963 -77.14085,169.02777 -77.14085,169.02777 -77.200745,169.02777 -77.26064,169.02777 -77.320535,169.02777 -77.38043,169.02777 -77.440325,169.02777 -77.50022,169.02777 -77.560115,169.02777 -77.62001,169.02777 -77.679905,169.02777 -77.7398,168.338963 -77.7398,167.650156 -77.7398,166.961349 -77.7398,166.272542 -77.7398,165.583735 -77.7398,164.894928 -77.7398,164.206121 -77.7398,163.517314 -77.7398,162.828507 -77.7398,162.1397 -77.7398,162.1397 -77.679905,162.1397 -77.62001,162.1397 -77.560115,162.1397 -77.50022,162.1397 -77.440325,162.1397 -77.38043,162.1397 -77.320535,162.1397 -77.26064,162.1397 -77.200745,162.1397 -77.14085))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 31 Jul 2014 00:00:00 GMT", "description": "The relatively pristine Antarctic continent with its extensive maritime zone represents a unique location on the planet to investigate the long distance aerial transport and deposition of marine microorganisms. The vast extent of new sea ice that forms each winter around the continent results in large numbers of frost flowers, delicate ice-crystal structures of high salt content that form on the surface of the ice and are readily dispersed by wind. The proposed research builds on earlier work in the Arctic and tests the new hypothesis that wind-borne frost flowers provide an effective mechanism for the transport of marine bacteria over long distances, one that can be uniquely sourced and tracked by the frost flower salt signature in the Antarctic realm. A highly resolved genomic snapshot of the microbial community will be acquired at each stage in the transport path, which will track decreasing fractions of the marine microbial community as it freezes into sea ice, incorporates into frost flowers, converts to aerosols, and ultimately deposits within continental snowpack. En route from sea ice to snowpack, marine bacteria will be exposed to an array of environmental stresses, including high salinity, low temperatures, UV light and potential desiccation. A parallel proteomic analysis will enable an evaluation of the microbial response to these extreme conditions and potential survival mechanisms that allow persistence or eventual colonization of deposition sites across Antarctica. Current understanding of microbes in the Antarctic atmosphere is based on a limited number of microscopic and culture-based assays and a single report of low-resolution 16S RNA gene sequence analysis. The research will broadly impact understanding of atmospheric microbiology, from source to deposition, and various issues of microbial survival, colonization, endemism, and diversity under extreme conditions. In addition to venues that reach the scientific community, the research team will develop a permanent multi-media and artifact-based exhibit on Antarctic Microbial Transport that will be showcased at Seattle\u0027s Pacific Science Center (PSC), which educates nearly a million visitors annually.", "east": 169.02777, "geometry": "POINT(165.583735 -77.440325)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.14085, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Deming, Jody", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.7398, "title": "High Resolution Genomic and Proteomic Analyses of a Microbial Transport Mechanism from Antarctic Marine Waters to Permanent Snowpack", "uid": "p0000356", "west": 162.1397}, {"awards": "1045215 Gooseff, Michael", "bounds_geometry": "POLYGON((160 -77.25,160.5 -77.25,161 -77.25,161.5 -77.25,162 -77.25,162.5 -77.25,163 -77.25,163.5 -77.25,164 -77.25,164.5 -77.25,165 -77.25,165 -77.375,165 -77.5,165 -77.625,165 -77.75,165 -77.875,165 -78,165 -78.125,165 -78.25,165 -78.375,165 -78.5,164.5 -78.5,164 -78.5,163.5 -78.5,163 -78.5,162.5 -78.5,162 -78.5,161.5 -78.5,161 -78.5,160.5 -78.5,160 -78.5,160 -78.375,160 -78.25,160 -78.125,160 -78,160 -77.875,160 -77.75,160 -77.625,160 -77.5,160 -77.375,160 -77.25))", "dataset_titles": "Are the Dry Valleys Getting Wetter? A Preliminary Assessment of Wetness Across the McMurdo Dry Valleys Landscape", "datasets": [{"dataset_uid": "600131", "doi": "10.15784/600131", "keywords": "Antarctica; Climate; Critical Zone; Dry Valleys; Radar; Soil Moisture", "people": "Gooseff, Michael N.", "repository": "USAP-DC", "science_program": null, "title": "Are the Dry Valleys Getting Wetter? A Preliminary Assessment of Wetness Across the McMurdo Dry Valleys Landscape", "url": "https://www.usap-dc.org/view/dataset/600131"}], "date_created": "Tue, 01 Jul 2014 00:00:00 GMT", "description": "Intellectual Merit: Until recently, wetted soils in the Dry Valleys were generally only found adjacent to streams and lakes. Since the warm austral summer of 2002, numerous ?wet spots? have been observed far from shorelines on relatively flat valley floor locations and as downslope fingers of flow on valley walls. The source of the water to wet these soils is unclear, as is the spatial and temporal pattern of occurrence from year to year. Their significance is potentially great as enhanced soil moisture may change the thermodynamics, hydrology, and erosion rate of surface soils, and facilitate transport of materials that had previously been stable. These changes to the soil active layer could significantly modify permafrost and ground ice stability within the Dry Valleys. The PIs seek to investigate these changes to address two competing hypotheses: that the source of water to these ?wet spots? is ground ice melt and that the source of this water is snowmelt. The PIs will document the spatiotemporal dynamics of these wet areas using high frequency remote sensing data from Quickbird and Wordview satellites to document the occurrence, dimensions, and growth of wet spots during the 2010-\u00ad11 and 2011-\u00ad12 austral summers. They will test their hypotheses by determining whether wet spots recur in the same locations in each season, and they will compare present to past distribution using archived imagery. They will also determine whether spatial snow accumulation patterns and temporal ablation patterns are coincident with wet spot formation. Broader impacts: One graduate student will be trained on this project. Findings will be reported at scientific meetings and published in peer reviewed journals. They will also develop a teaching module on remote sensing applications to hydrology for the Modular Curriculum for Hydrologic Advancement and an innovative prototype project designed to leverage public participation in mapping wet spots and snow patches across the Dry Valleys through the use of social media and mobile computing applications.", "east": 165.0, "geometry": "POINT(162.5 -77.875)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; AMD; USAP-DC; ANALYTICAL LAB; Amd/Us", "locations": null, "north": -77.25, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Gooseff, Michael N.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.5, "title": "EAGER: Are the Dry Valleys Getting Wetter? A Preliminary Assessment of Wetness Across the McMurdo Dry Valleys Landscape", "uid": "p0000471", "west": 160.0}, {"awards": "0944042 Warren, Joseph", "bounds_geometry": "POLYGON((-70 -59,-68 -59,-66 -59,-64 -59,-62 -59,-60 -59,-58 -59,-56 -59,-54 -59,-52 -59,-50 -59,-50 -59.7,-50 -60.4,-50 -61.1,-50 -61.8,-50 -62.5,-50 -63.2,-50 -63.9,-50 -64.6,-50 -65.3,-50 -66,-52 -66,-54 -66,-56 -66,-58 -66,-60 -66,-62 -66,-64 -66,-66 -66,-68 -66,-70 -66,-70 -65.3,-70 -64.6,-70 -63.9,-70 -63.2,-70 -62.5,-70 -61.8,-70 -61.1,-70 -60.4,-70 -59.7,-70 -59))", "dataset_titles": "Data from expdition LMG1010; Expedition Data; Expedition data of LMG1010; Expedition data of LMG1110", "datasets": [{"dataset_uid": "002723", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1010", "url": "https://www.rvdata.us/search/cruise/LMG1010"}, {"dataset_uid": "000153", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Data from expdition LMG1010", "url": "https://www.rvdata.us/search/cruise/LMG1010"}, {"dataset_uid": "001445", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1110"}, {"dataset_uid": "002671", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1110", "url": "https://www.rvdata.us/search/cruise/LMG1110"}], "date_created": "Tue, 03 Dec 2013 00:00:00 GMT", "description": "The importance of gelatinous zooplankton in marine systems worldwide is increasing. In Southern Ocean, increasing salp densities could have a detrimental effect on higher predators, including penguins, fur seals, and baleen whales. The proposed research is a methods-develoment project that will improve the capability to indirectly assess abundances and distributions of salps in the Southern Ocean through acoustic surveys. Hydrographic, net tow, and acoustic backscatter data will be collected in the waters surrounding the South Shetland Islands and the Antarctic peninsula, where both krill and salps are found and compete for food. Shipboard experimental manipulations and measurements will lead to improved techniques for assessment of salp biomass acoustically. Experiments will focus on material properties (density and sound speed), size and shape of salps, as well as how these physical properties will vary with the salp\u0027s environment, feeding rate, and reproductive status. In the field, volume backscattering data from an acoustic echosounder will be collected at the same locations as the net tows to enable comparison of net and acoustic estimates of salp abundance. A physics-based scattering model for salps will be developed and validated, to determine if multiple acoustic frequencies can be used to discriminate between scattering associated with krill swarms and that from salp blooms. During the same period as the Antarctic field work, a parallel outreach and education study will be undertaken in Long Island, New York examining local gelatinous zooplankton. This study will enable project participants to learn and practice research procedures and methods before traveling to Antarctica; provide a comparison time-series that will be used for educational purposes; and include many more students and teachers in the research project than would be able to participate in the Antarctic field component.", "east": -50.0, "geometry": "POINT(-60 -62.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "R/V LMG; Not provided", "locations": null, "north": -59.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Warren, Joseph", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -66.0, "title": "Acoustic Assessment of Southern Ocean Salps and Their Ecosystem Impact", "uid": "p0000481", "west": -70.0}, {"awards": "0838937 Costa, Daniel; 0838911 Hofmann, Eileen; 0838892 Burns, Jennifer", "bounds_geometry": "POLYGON((160 -68,162 -68,164 -68,166 -68,168 -68,170 -68,172 -68,174 -68,176 -68,178 -68,180 -68,180 -68.8,180 -69.6,180 -70.4,180 -71.2,180 -72,180 -72.8,180 -73.6,180 -74.4,180 -75.2,180 -76,178 -76,176 -76,174 -76,172 -76,170 -76,168 -76,166 -76,164 -76,162 -76,160 -76,160 -75.2,160 -74.4,160 -73.6,160 -72.8,160 -72,160 -71.2,160 -70.4,160 -69.6,160 -68.8,160 -68))", "dataset_titles": "Weddell seal dive behavior and rhythmicity from 2010-2012 in the Ross Sea; Weddell seals as autonomous sensors of the winter oceanography of the Ross Sea", "datasets": [{"dataset_uid": "601835", "doi": "10.15784/601835", "keywords": "Aerobic; Antarctica; Cryosphere; Weddell Seal", "people": "Shero, Michelle", "repository": "USAP-DC", "science_program": null, "title": "Weddell seal dive behavior and rhythmicity from 2010-2012 in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601835"}, {"dataset_uid": "600025", "doi": "10.15784/600025", "keywords": "Antarctica; Biota; Oceans; Ross Sea; Southern Ocean", "people": "Costa, Daniel", "repository": "USAP-DC", "science_program": null, "title": "Weddell seals as autonomous sensors of the winter oceanography of the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600025"}, {"dataset_uid": "600101", "doi": "10.15784/600101", "keywords": "Biota; Oceans; Ross Sea; Seals; Southern Ocean", "people": "Burns, Jennifer", "repository": "USAP-DC", "science_program": null, "title": "Weddell seals as autonomous sensors of the winter oceanography of the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600101"}], "date_created": "Mon, 11 Nov 2013 00:00:00 GMT", "description": "Abstract \u003cbr/\u003eThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). \u003cbr/\u003e\u003cbr/\u003eMarine mammals of the Southern Ocean have evolved diverse life history patterns and foraging strategies to accommodate extreme fluctuations in the physical and biological environment. In light of ongoing climate change and the dramatic shifts in the extent and persistence of sea ice in the Ross Sea, it is critical to understand how Weddell seals, Leptonychotes weddellii, a key apex predator, select and utilize foraging habitats. Recent advances in satellite-linked animal-borne conductivity, temperature and depth (CTD) tags make it possible to simultaneously collect data on seal locations, their diving patterns, and the temperature and salinity profiles of the water columns they utilize. In other ecosystems, such data have revealed that marine predators selectively forage in areas where currents and fronts serve to locally concentrate prey resources, and that these conditions are required to sustain populations. Weddell seals will be studied in McMurdo Sound and at Terra Nova Bay, Ross Sea and will provide the first new data on Weddell seal winter diving behavior and habitat use in almost two decades. The relationship between an animal\u0027s diving behavior and physical habitat has enormous potential to enhance monitoring studies and to provide insight into how changes in ice conditions (due either to warming or the impact of large icebergs, such as B15) might impact individual time budgets and foraging success. The second thrust of this project is to use the profiles obtained from CTD seal tags to model the physical oceanography of this region. Current mathematical models of physical oceanographic processes in the Southern Ocean are directed at better understanding the role that it plays in global climate processes, and the linkages between physical and biological oceanographic processes. However, these efforts are limited by the scarcity of oceanographic data at high latitudes in the winter months; CTD tags deployed on animals will collect data at sufficient spatial and temporal resolution to improve data density. The project will contribute to two IPY endorsed initiatives: MEOP (Marine Mammals as Explorers of the Ocean Pole to Pole) and CAML (Census of Antarctic Marine Life). In addition, the highly visual nature of the data and analysis lends itself to public and educational display and outreach, particularly as they relate to global climate change, and we have collaborations with undergraduate and graduate training programs, the Seymour Marine Discovery Center, and the ARMADA program to foster these broader impacts.", "east": 180.0, "geometry": "POINT(170 -72)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -68.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Burns, Jennifer; Hofmann, Eileen; Costa, Daniel", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.0, "title": "Collaborative Research: Weddell seals as autonomous sensors of the winter oceanography of the Ross Sea", "uid": "p0000661", "west": 160.0}, {"awards": "1043749 Rouse, Gregory", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1105", "datasets": [{"dataset_uid": "002659", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1105", "url": "https://www.rvdata.us/search/cruise/NBP1105"}], "date_created": "Mon, 24 Jun 2013 00:00:00 GMT", "description": "The west Antarctic Peninsula is warming rapidly, and continuing changes in the thermal regime will likely result in severe consequences for marine fauna, including potential extinction of strongly adapted stenotherms, and invasions from neighboring faunas. Initial impacts of climate change may result in changes in connectivity among populations of the same species. These changes may will be undetectable by direct observation, but may be assessed via genetic connectivity, i.e. differences in allele or haplotype frequencies among populations can be used to infer levels of gene flow. The proposed research will explore the role that the Scotia Arc plays in connecting populations from South America to Antarctica, a corridor identified as a likely entry route for invaders into Antarctica. It also will examine the way in which cryptic species may confound our knowledge of broad-scale distributions, and in doing so, make contributions towards understanding biodiversity and testing the paradigm of circumpolarity in Antarctica. The principal investigator will to collect multi-locus genetic data across \u0027species\u0027 from a broad suite of benthic marine invertebrate phyla, from multiple locations, in order to address hypotheses regarding speciation and connectivity, to estimate demographic population changes, and to identify the underlying processes that drive observed phylogeographic patterns. Comparative phylogeography is a particularly valuable approach because it enables the identification of long-term barriers and refugia common to groups of species and is consequently highly relevant to conservation planning. Moreover, this work will form a valuable baseline for detecting future changes in connectivity. The results of the research will be disseminated through peer-reviewed publications and presentations at conferences. In addition, the project will support the interdisciplinary training of a female graduate student, two undergraduate students, and host additional summer students through the STARS program at SIO, which helps minority students prepare for graduate school. This project will integrate research and education through conducting an interdisciplinary workshop that brings together Earth Science and Biology high school teachers. This workshop aims to assist teachers derive their own curricula uniting plate tectonics, ocean history and evolution, supporting a new high school earth sciences program. Information generated by this project will also directly feed into international efforts to design a series of Marine Protected Areas (MPAs) in Antarctica.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rouse, Gregory", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Using molecular data to test connectivity and the circumpolar paradigm for Antarctic marine invertebrates", "uid": "p0000847", "west": null}, {"awards": "0838934 Wiens, Douglas; 0838973 Nyblade, Andrew", "bounds_geometry": "POLYGON((40 -76,50 -76,60 -76,70 -76,80 -76,90 -76,100 -76,110 -76,120 -76,130 -76,140 -76,140 -76.8,140 -77.6,140 -78.4,140 -79.2,140 -80,140 -80.8,140 -81.6,140 -82.4,140 -83.2,140 -84,130 -84,120 -84,110 -84,100 -84,90 -84,80 -84,70 -84,60 -84,50 -84,40 -84,40 -83.2,40 -82.4,40 -81.6,40 -80.8,40 -80,40 -79.2,40 -78.4,40 -77.6,40 -76.8,40 -76))", "dataset_titles": "Seismological Record ID# ZM 2007-12; Seismological Record Network Code# ZM (full data link not provided)", "datasets": [{"dataset_uid": "000149", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Seismological Record ID# ZM 2007-12", "url": "http://www.iris.edu/"}, {"dataset_uid": "000152", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Seismological Record Network Code# ZM (full data link not provided)", "url": "http://www.iris.edu/"}], "date_created": "Mon, 21 Jan 2013 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The high elevations of East Antarctica are critical in localizing the initial Cenozoic glaciation and stabilizing it with respect to melting during warm interglacials. However, the geological history for this region and the geophysical mechanism for maintaining the highlands are poorly understood. In 2007-2009, an array of 24 broadband seismographs (named GAMSEIS) was installed across the Gamburtsev Mountains area of the East Antarctic Plateau as part of the Antarctica?s Gamburtsev Province (AGAP) International Polar Year project. The IPY AGAP/GAMSEIS program included plans by other international partners to install seismographs at locations along the flanks of the Gamburtsev Mountains and in other East Antarctic regions. The proposed project will continue operating six of the deployed AGAP/GAMSEIS stations for two more years together with two new broadband seismic stations added to broaden the geographic scope of the array. Most stations will be located at the existing U.S. Autonomous Geophysical Observatories and the USAP fuel cache locations in order to minimize logistical support. This array, combined with seismographs deployed by China and Japan (and possibly Australia, France, and Italy in near future) will provide a sparse but large-scale network of seismometers for the longer-term studies of the crustal and upper mantle structures underneath the East Antarctic Plateau. Continued reliance on students provides a broader impact to this proposed research and firmly grounds this effort in its educational mission.", "east": 140.0, "geometry": "POINT(90 -80)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Wiens, Douglas; Nyblade, Andrew", "platforms": "Not provided", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -84.0, "title": "Collaborative Research: Polenet East: An International Seismological Network for East Antarctica", "uid": "p0000504", "west": 40.0}, {"awards": "0738975 Baker, Ian", "bounds_geometry": null, "dataset_titles": "Siple Dome A (SDMA) Grain Orientation 640 - 790 Meters", "datasets": [{"dataset_uid": "609526", "doi": "10.7265/N53T9F5X", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Sample/collection Description; Sample/Collection Description; Siple Dome; Siple Dome Ice Core; South Pole; WAISCORES", "people": "Obbard, Rachel; Sieg, Katherine; Baker, Ian", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Siple Dome A (SDMA) Grain Orientation 640 - 790 Meters", "url": "https://www.usap-dc.org/view/dataset/609526"}], "date_created": "Mon, 26 Nov 2012 00:00:00 GMT", "description": "This award supports a project to fully characterize the microstructure in ice cores, in particular the microstructural locations of impurities, grain orientations and strain gradients. This work will complement the optical observations, electrical conductivity measurement, and precise, detailed measurements of the soluble ion and gas contents that are performed by others. Linking the concentrations of soluble ions and gases, measured to a few parts per billion, to the optically determined annual layer structure and the stable isotope data in ice cores has enabled a great deal to be established about the concentrations and depth/age distributions of particles, trace gases and impurities for several polar ice cores. Ice core studies carried out by several groups contribute immensely to our understanding of paleoclimate and, to our ability to predict future climate change. The work will build on previous measurements and technique development in this area, as well as focusing on new techniques to characterize ice cores. The work will use both scanning electron microscopy (SEM) coupled with X-ray energy dispersive spectroscopy (EDS) and confocal scanning optical microscopy coupled with Raman spectroscopy (RS) to determine the microstructural locations of impurities and correlate this information with depth/age, and impurity type and concentration for several polar ice cores. The Broader Impacts of the proposed work are that knowledge of the location of impurities coupled with the grain orientation (both c- and a-axis) and grain misorientation information will allow paleoclimatologists to better interpret ice core data and other scientists to understand and model the physical and mechanical properties of natural ice sheets. Other Broader Impacts of the work are that the work will be performed and lead to the education of a Ph.D. student. At the end of the project, as well as the knowledge gained from coursework, the graduate student will have experience in ice core specimen preparation and characterization using scanning electron microscopy, x-ray microanalysis, confocal scanning microscopy, Raman spectroscopy and ion chromatography. Results from the research will be published in refereed journals, presented at conferences, and placed on a web page.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e SCANNING ELECTRON MICROSCOPES", "is_usap_dc": true, "keywords": "FEI Xl30 Environmental Scanning Electron Microscope - Field Emission Gun (esem - Feg); LABORATORY; Electron Backscatter Diffraction", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Baker, Ian; Obbard, Rachel; Sieg, Katherine", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Advanced Microstructural Characterization of Polar Ice Cores", "uid": "p0000178", "west": null}, {"awards": "0838914 Wannamaker, Philip", "bounds_geometry": "POLYGON((141.01732 -82.13,144.910279 -82.13,148.803238 -82.13,152.696197 -82.13,156.589156 -82.13,160.482115 -82.13,164.375074 -82.13,168.268033 -82.13,172.160992 -82.13,176.053951 -82.13,179.94691 -82.13,179.94691 -82.351835,179.94691 -82.57367,179.94691 -82.795505,179.94691 -83.01734,179.94691 -83.239175,179.94691 -83.46101,179.94691 -83.682845,179.94691 -83.90468,179.94691 -84.126515,179.94691 -84.34835,176.053951 -84.34835,172.160992 -84.34835,168.268033 -84.34835,164.375074 -84.34835,160.482115 -84.34835,156.589156 -84.34835,152.696197 -84.34835,148.803238 -84.34835,144.910279 -84.34835,141.01732 -84.34835,141.01732 -84.126515,141.01732 -83.90468,141.01732 -83.682845,141.01732 -83.46101,141.01732 -83.239175,141.01732 -83.01734,141.01732 -82.795505,141.01732 -82.57367,141.01732 -82.351835,141.01732 -82.13))", "dataset_titles": "Agglutinated Foraminifera, genome sequencing data; Rift Mechanisms and Thermal Regime of the Lithosphere across Beardmore Glacier Region, Central Transantarctic Mountains, from Magnetotelluric Measurements", "datasets": [{"dataset_uid": "000211", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Agglutinated Foraminifera, genome sequencing data", "url": "http://www.ncbi.nlm.nih.gov/sites/myncbi/collections/public/1vwfrm7rJme2hrzl6smGVhpk-/"}, {"dataset_uid": "600102", "doi": "10.15784/600102", "keywords": "Antarctica; Magnetotelluric; Potential Field; Solid Earth; Transantarctic Mountains", "people": "Wannamaker, Philip", "repository": "USAP-DC", "science_program": null, "title": "Rift Mechanisms and Thermal Regime of the Lithosphere across Beardmore Glacier Region, Central Transantarctic Mountains, from Magnetotelluric Measurements", "url": "https://www.usap-dc.org/view/dataset/600102"}], "date_created": "Mon, 12 Nov 2012 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The investigators will examine competing hypotheses for the mechanism of extension and creation of the Transantarctic Mountains, and evolution of the thermal regimes of rifted West Antarctica and stable East Antarctica using magnetotelluric (MT) profiles. Surrounded almost entirely by ocean ridges, Antarctica is a special tectonic situation because of the need to make accommodation space for rifting in the Transantarctic region. In the MT method, temporal variations in the Earth\u0027s natural electromagnetic field are used as source fields to probe the electrical resistivity structure in the depth range of 1 to 200 km, or more. Geophysical methods, such as MT, are appropriate in Antarctica because of the predominance of thick ice cover over most of the Continent and the difficult operating environment. The proposed effort will consist of approximately 50 sites over a distance approaching 500 km with a 10 km average spacing, oriented normal to the Transantarctic Mountains (TAM), in the Beardmore glacier area. High quality MT soundings will be collected over thick ice sheets using a custom electrode preamp design, updated from previous Antarctic projects. Data acquisition will take place over two field seasons. The primary goals are three-fold: to establish the location of the deeper tectonic transition between East and West Antarctica that may be offset from the physiographic transition at the surface, using deep resistivity structure distinguish between modes of extensional upwelling and magmatism that may be vertically non-uniform, depth and magnitude of quasi-layered deep crustal low resistivity, particularly below West Antarctica, will be used to estimate crustal heat flux into the ice sheet base.", "east": 179.94691, "geometry": "POINT(160.482115 -83.239175)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -82.13, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Earth Sciences", "paleo_time": null, "persons": "Bowser, Samuel; Wannamaker, Philip", "platforms": "Not provided", "repo": "NCBI GenBank", "repositories": "NCBI GenBank; USAP-DC", "science_programs": null, "south": -84.34835, "title": "Rift Mechanisms and Thermal Regime of the Lithosphere across Beardmore Glacier Region, Central Transantarctic Mountains, from Magnetotelluric Measurements", "uid": "p0000247", "west": 141.01732}, {"awards": "0739684 Hatcher, Patrick", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 26 Sep 2012 00:00:00 GMT", "description": "This award supports a project to fully develop the analytical protocols needed to exploit a relatively new technique for the analysis of soluble organic matter in ice core samples. The technique couples Electrospray ionization to high resolution Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS). Sample volume will be reduced and pre-concentration steps will be eliminated. Following method optimization a suite of ice core samples will be studied from several Antarctic and Greenland locations to address several hypothesis driven research questions. Preliminary results show that a vast record of relatively high molecular weight organic material exists in ice core samples and intriguing results from a few samples warrant further investigation. Several important questions related to developing a better understanding of the nature and paleo record of organic matter in ice cores will be addressed. These include developing a better understanding of the origin of nitrogen and sulfur isotopes in pre-industrial vs. modern samples, developing the methods to apply molecular biomarker techniques, routinely used by organic geochemists for sediment analyses, to the analysis of organic matter in ice cores, tracking the level of oxidation of homologous series of compounds and using them as a proxy for atmospheric oxidant levels in the past and determining whether or not high resolution FTICR mass spectral analysis can provide the ice core community with a robust method to analyze organic materials at the molecular level. The intellectual merit of this work is that this analytical method will provide a new understanding of the nature of organic matter in ice, possibly leading to the discovery of multitudes of molecular species indicative of global change processes whose abundances can be compared with other change proxies. The proposed studies are of an exploratory nature and potentially transformative for the field of ice core research and cryobiology. The broader impacts of these studies are that they should provide compelling evidence regarding organic matter sources, atmospheric processing and anthropogenic inputs to polar ice and how these have varied over time. The collaborative work proposed here will partner atmospheric chemistry/polar ice chemistry expertise with organic geochemistry expertise, resulting in significant contributions to both fields of study and significant advances in ice core analysis. Training of both graduate and undergraduate students will be a key component of the project and students will be involved in collaborative research using advanced analytical instrumentation, presentation of research results at national meetings, and will participate in manuscript preparation.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": false, "keywords": "Ice Core; Isotope; Organic Matter; Nitrogen; Sulfur; Not provided; LABORATORY; Mass Spectrometry; COMPUTERS; Molecular", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hatcher, Patrick; Grannas, Amanda", "platforms": "Not provided; OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Molecular Level Characterization of Organic Matter in Ice Cores using High-resolution FTICR mass spectrometry", "uid": "p0000707", "west": null}, {"awards": "1241487 Adams, Byron", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 06 Jul 2012 00:00:00 GMT", "description": "This award will support the participation of US scientists in an international planning workshop devoted to discussions of how to best facilitate and coordinate international efforts for terrestrial system studies at the McMurdo Dry Valleys of Antarctica. To date, various aspects of the different Dry Valley landscape features (lakes, soils, glaciers, streams) and their biota have been studied most intensively by US and New Zealand scientists, but these efforts could significantly improve their explanatory power if they were coordinated so as to reduce redundancy, decrease environmental degradation and, most importantly, produce comparable datasets. Additionally, many of the present environmental management programs are based on the past baseline composition and location of biotic communities. As these communities become rearranged across the valleys in the future there is interest in assessing whether today\u0027s management plans are adequate. To efficiently move these research programs forward for the McMurdo Dry Valleys requires a coordinated, interdisciplinary, long-term data monitoring and observation network. The ultimate objectives of the workshop are to: i) identify the optimal, complementary suites of measurements required to assess and address key processes associated with environmental change in Dry Valley ecosystems; ii) develop standards and protocols for gathering the most critical biotic and abiotic measurements associated with the key processes driving environmental change; iii) generate a draft data coordination and development plan that will maximize the utility of these data; iv) assess the effectiveness of current McMurdo Dry Valley ASMA (Antarctic Special Management Area) environmental protection guidelines.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Adams, Byron", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "A Planning Workshop for a McMurdo Dry Valleys Terrestrial Observation Network", "uid": "p0000126", "west": null}, {"awards": "0738658 Price, P. Buford", "bounds_geometry": "POINT(112.1125 -79.4638)", "dataset_titles": "Access to data; data from one of three optical logs we made at WAIS Divide; WAIS Divide Laser Dust Logger Data", "datasets": [{"dataset_uid": "001349", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Access to data", "url": "http://icecube.berkeley.edu/~bay/wdc/"}, {"dataset_uid": "609540", "doi": "10.7265/N5C53HSG", "keywords": "Antarctica; Atmosphere; Chemistry:ice; Chemistry:Ice; Dust; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Laser Dust Logger; WAIS Divide Ice Core", "people": "Bay, Ryan", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Laser Dust Logger Data", "url": "https://www.usap-dc.org/view/dataset/609540"}, {"dataset_uid": "000188", "doi": "", "keywords": null, "people": null, "repository": "USAP-DC", "science_program": null, "title": "data from one of three optical logs we made at WAIS Divide", "url": "http://icecube.berkeley.edu/~bay/wdc/"}], "date_created": "Tue, 19 Jun 2012 00:00:00 GMT", "description": "This award supports a project to use two new scanning fluorimeters to map microbial concentrations vs depth in the WAIS Divide ice core as portions of it become available at NICL, and selected portions of the GISP2 ice core for inter-hemispheric comparison. Ground-truth calibrations with microbes in ice show that the instruments are sensitive to a single cell and can scan the full length of a 1-meter core at 300-micron intervals in two minutes. The goals of these studies will be to exploit the discovery that microbes are transported onto ice, in clumps, several times per year and that at rare intervals (not periodically) of ~104 years, a much higher flux, sometimes lasting \u003e1 decade, reaches the ice. From variations ranging from seasonal to millennial to glacial scale in the arrival time distribution of phototrophs, methanogens, and total microbes in the Antarctic and Arctic ice, the investigators will attempt to determine oceanic and terrestrial sources of these microbes and will look for correlations of microbial bursts with dust concentration and temperature proxies. In addition the project will follow up on the discovery that the rare instances of very high microbial flux account for some of the\"gas artifacts\" in ice cores - isolated spikes of excess CH4 and N2O that have been discarded by others in previous climate studies. The intellectual merit of this project is that it will exploit scanning fluorimetry of microbes as a powerful new tool for studies ranging from meteorology to climatology to biology, especially when combined with mapping of dust, gases, and major element chemistry in ice cores. In 2010-11 the WAIS Divide borehole will be logged with the latest version of the dust logger. The log will provide mm-scale depth resolution of dust concentration and of volcanic ash layers down the entire depth of the borehole. The locations of ash layers in the ice will be determined and chemical analyses of the ash will be analyzed in order to determine provenance. By comparing data from the WAIS Divide borehole with data from other boreholes and with chemical data (obtained by others) on volcanic layers, the researchers will examine the relationship between the timing of volcanic eruptions and abrupt climate change. Results from this project with the scanning fluorimeters and the dust logger could have applications to planetary missions, borehole oceanography, limnology, meteorology, climate, volcanology, and ancient life in ice. A deeper understanding of the causes of abrupt climate change, including a causal relationship with volcanic explosivity, would enable a better understanding of the adverse effects on climate. The broader impact of the project is that it will provide training to students and post-docs from the U. S. and other countries.", "east": 112.1125, "geometry": "POINT(112.1125 -79.4638)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e OPTICAL DUST LOGGERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e OPTICAL DUST LOGGERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS", "is_usap_dc": true, "keywords": "Dust Loggers; Dust Concentration; Ice Core; West Antarctic Ice Sheet; LABORATORY; Microbial; Fluorimetry; GROUND-BASED OBSERVATIONS; Meteorology; Climatologymeteorologyatmosphere; Ice", "locations": "West Antarctic Ice Sheet", "north": -79.4638, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bay, Ryan; Price, Buford; Souney, Joseph Jr.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "PI website", "repositories": "PI website; USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.4638, "title": "Climatology, Meteorology, and Microbial Metabolism in Ice with Dust Loggers and Fluorimetry", "uid": "p0000009", "west": 112.1125}, {"awards": "0739654 Catania, Ginny; 0739372 Conway, Howard", "bounds_geometry": null, "dataset_titles": "Coastal and Terminus History of the Eastern Amundsen Sea Embayment, West Antarctica, 1972 - 2011; Ice Flow History of the Thwaites Glacier, West Antarctica", "datasets": [{"dataset_uid": "609522", "doi": "10.7265/N5CC0XNK", "keywords": "Amundsen Sea; Antarctica; Climate Change; Coastline; GIS Data; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Satellite Data Interpretation", "people": "Andrews, Alan G.; Catania, Ginny; Markowski, Michael; Macgregor, Joseph A.", "repository": "USAP-DC", "science_program": null, "title": "Coastal and Terminus History of the Eastern Amundsen Sea Embayment, West Antarctica, 1972 - 2011", "url": "https://www.usap-dc.org/view/dataset/609522"}, {"dataset_uid": "609463", "doi": "10.7265/N5RR1W6X", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Flow Lines; Thwaites Glacier", "people": "Catania, Ginny; Conway, Howard; Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Ice Flow History of the Thwaites Glacier, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/609463"}], "date_created": "Wed, 30 May 2012 00:00:00 GMT", "description": "Catania 0739654\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to study the Amundsen Sea drainage system and improve understanding of the impact of recent glaciological changes as an aid to predicting how this region will change in the future. The intellectual merit of the work is that the Amundsen Sea drainage system has been a recent focus for glaciological research because of rapid changes occurring there as a result of grounding line retreat. The work will focus on the regions of flow transition and will map the internal stratigraphy of the ice sheet across the Thwaites Glacier shear margins and use the age and geometry of radar-detected internal layers to interpret ice flow history. Thwaites Glacier (one of the main pathways for ice drainage in the region) has recently widened and may continue to do so in the near future. Thwaites Glacier may be particularly vulnerable to grounding line retreat because it lacks a well-defined subglacial channel. The subglacial environment exerts strong control on ice flow and flow history will be mapped in the context of bed topography and bed reflectivity. The plan is to use existing ice-penetrating radar data and coordinate with planned upcoming surveys to reduce logistical costs. The work proposed here will take three years to complete but no additional fieldwork in Antarctica is required. More detailed ground-based geophysical (radar and seismic) experiments will be needed at key locations to achieve our overall goal and the work proposed here will aid in identifying those regions. The broader impacts of the project are that it will initiate a new collaboration among radar communities within the US including those that are on the forefront of radar systems engineering and those that are actively involved in radar-derived internal layer and bed analysis. The project will also provide support for a postdoctoral researcher and a graduate student, thus giving them exposure to a variety of methodologies and scientific issues. Finally, there are plans to further develop the \"Wired Antarctica\" website designed by Ginny Catania with the help of a student-teacher. This will allow for the existing lesson plans to be updated to Texas State standards so that they can be used more broadly within state middle and high schools.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e SAR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e TM; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e ALTIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR", "is_usap_dc": true, "keywords": "ERS-1; Coastal; Terminus; LABORATORY; Subglacial; Glacier; Not provided; Thwaites Glacier; Antarctica; LANDSAT; Internal Stratigraphy; West Antarctica; Internal Layers; Amundsen Sea; FIELD INVESTIGATION; FIELD SURVEYS; Glaciers; LANDSAT-5; Radar; Seismic", "locations": "Coastal; Antarctica; Thwaites Glacier; Amundsen Sea; West Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard; Catania, Ginny; Markowski, Michael; Macgregor, Joseph A.; Andrews, Alan G.; Fudge, T. J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e EUROPEAN REMOTE SENSING SATELLITE (ERS) \u003e ERS-1; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e LANDSAT \u003e LANDSAT; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e LANDSAT \u003e LANDSAT-5", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Ice-flow history of the Thwaites Glacier, West Antarctica", "uid": "p0000143", "west": null}, {"awards": "0537930 Steig, Eric; 0537661 Cuffey, Kurt; 0537593 White, James", "bounds_geometry": "POINT(-112.08 -79.47)", "dataset_titles": "Stable Isotope Lab at INSTAAR, University of Colorado; WAIS ice core isotope data #342, 347, 348, 349, 350, 351 (full data link not provided)", "datasets": [{"dataset_uid": "000140", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "WAIS ice core isotope data #342, 347, 348, 349, 350, 351 (full data link not provided)", "url": "http://www.waisdivide.unh.edu/"}, {"dataset_uid": "002561", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Stable Isotope Lab at INSTAAR, University of Colorado", "url": "http://instaar.colorado.edu/sil/about/index.php"}], "date_created": "Mon, 09 Apr 2012 00:00:00 GMT", "description": "This award supports analyses of stable isotopes of water, dD, d18O and deuterium excess in the proposed West Antarctic Ice Sheet Divide (WAIS) deep ice core. The project will produce a continuous and high-resolution reconstruction of stable isotope ratios for the new core. dD and d18O values provide estimates of temperature change at the ice core site. Deuterium excess provides estimates of ocean surface conditions, such as sea surface temperature, at the moisture source areas. This new ice core is ideally situated to address questions ranging from ice sheet stability to abrupt climate change. WAIS Divide has high enough snowfall rates to record climate changes on annual to decadal time scales. It should also have ice old enough to capture the last interglacial period in detail. The West Antarctic ice sheet is the subject of great scrutiny as our modern climate warms and sea level rises. What are the prospects for added sea level rise from ice released by this ice sheet? Understanding how this ice sheet has responded to climate change in the past, which the data collected in this project will help to assess, is critical to answering this question. The high temporal resolution available in the WAIS Divide core will provide the best available basis for inter-comparison of millennial-scale climate changes between the poles, and thus a better understanding of the spatial expression and dynamics of rapid climate change events. Finally, the location of this core in the Pacific sector of West Antarctica makes it well situated for examining the influence of the tropical Pacific on Antarctica climate, on longer timescales than are available from the instrumental climate record. Analyses will include the measurement of sub-annually resolved isotope variations in the uppermost parts of the core, measurements at annual resolution throughout the last 10,000 years and during periods of rapid climate change prior to that, and measurements at 50-year resolution throughout the entire length of the core that is collected and processed during the period of this grant. We anticipate that this will be about half of the full core expected to be drilled. In terms of broader impacts, the PIs will share the advising of two graduate students, who will make this ice core the focus of their thesis projects. It will be done in an innovative multi-campus approach designed to foster a broader educational experience. As noted above, the data and interpretations generated by this proposal will address climate change questions not only of direct and immediate scientific interest, but also of direct and immediate policy interest.", "east": -112.08, "geometry": "POINT(-112.08 -79.47)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES", "is_usap_dc": true, "keywords": "West Antarctic Ice Sheet Divide; Not provided; Ice Core; WAIS Divide; LABORATORY; FIELD SURVEYS; Isotope; FIELD INVESTIGATION; Antarctica; West Antarctica; Stable Isotope Ratios; Antarctic; Ice Sheet; Deuterium", "locations": "WAIS Divide; West Antarctica; Antarctic; Antarctica; West Antarctic Ice Sheet Divide", "north": -79.47, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "White, James; Steig, Eric J.; Cuffey, Kurt M.; Souney, Joseph Jr.; Vaughn, Bruce", "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": "Project website", "repositories": "Project website", "science_programs": null, "south": -79.47, "title": "Collaborative Research: Stable Isotopes of Ice in the WAIS Divide Deep Ice Core", "uid": "p0000294", "west": -112.08}, {"awards": "0739769 Fricker, Helen", "bounds_geometry": "POLYGON((-57.22 74.58,-55.343 74.58,-53.466 74.58,-51.589 74.58,-49.712 74.58,-47.835 74.58,-45.958 74.58,-44.081 74.58,-42.204 74.58,-40.327 74.58,-38.45 74.58,-38.45 73.822,-38.45 73.064,-38.45 72.306,-38.45 71.548,-38.45 70.79,-38.45 70.032,-38.45 69.274,-38.45 68.516,-38.45 67.758,-38.45 67,-40.327 67,-42.204 67,-44.081 67,-45.958 67,-47.835 67,-49.712 67,-51.589 67,-53.466 67,-55.343 67,-57.22 67,-57.22 67.758,-57.22 68.516,-57.22 69.274,-57.22 70.032,-57.22 70.79,-57.22 71.548,-57.22 72.306,-57.22 73.064,-57.22 73.822,-57.22 74.58))", "dataset_titles": "Amery Ice Shelf metadata (IRIS); Columbia Glacier metadata (IRIS); Greenland Ice Sheet Seismic Network metadata (IRIS)", "datasets": [{"dataset_uid": "000100", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Amery Ice Shelf metadata (IRIS)", "url": "http://www.iris.edu/mda/X9?timewindow=2004-2007"}, {"dataset_uid": "000103", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Greenland Ice Sheet Seismic Network metadata (IRIS)", "url": "http://www.iris.edu/mda/_GLISN"}, {"dataset_uid": "000101", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Columbia Glacier metadata (IRIS)", "url": "http://www.iris.edu/mda/YM?timewindow=2004-2005"}], "date_created": "Thu, 22 Mar 2012 00:00:00 GMT", "description": "This award supports a project to strengthen collaborations between the various research groups working on iceberg calving. Relatively little is known about the calving process, especially the physics that governs the initiation and propagation of fractures within the ice. This knowledge gap exists in part because of the diverse range in spatial and temporal scales associated with calving (ranging from less than one meter to over a hundred kilometers in length scale). It is becoming increasingly clear that to predict the future behavior of the Antarctic Ice Sheet and its contribution to sea level rise, it is necessary to improve our understanding of iceberg calving processes. Further challenges stem from difficulties in monitoring and quantifying short-time and spatial-scale processes associated with ice fracture, including increased fracturing events in ice shelves or outlet glaciers that may be a precursor to disintegration, retreat or increased calving rates. Coupled, these fundamental problems currently prohibit the inclusion of iceberg calving into numerical ice sheet models and hinder our ability to accurately forecast changes in sea level in response to climate change. Seismic data from four markedly different environmental regimes forms the basis of the proposed research, and researchers most familiar with the datasets will perform all analyses. Extracting the similarities and differences across the full breadth of calving processes embodies the core of the proposed work, combining and improving methods previously developed by each group. Techniques derived from solid Earth seismology, including waveform cross-correlation and clustering will be applied to each data set allowing quantitative process comparisons on a significantly higher level than previously possible. This project will derive catalogues of glaciologically produced seismic events; the events will then be located and categorized based on their location, waveform and waveform spectra both within individual environments and between regions. The intellectual merit of this work is that it will lead to a better understanding of iceberg calving and the teleconnections between seismic events and other geophysical processes around the globe. The broader impacts of this work are that it relates directly to socio-environmental impacts of global change and sea level rise. Strong collaborations will form as a result of this research, including bolstered collaborations between the glacier and ice sheet communities, as well as the glaciology and seismology communities. Outreach and public dissemination of findings will be driven by SIO\u0027s Visualization Center, and Birch Aquarium, hosting presentations devoted to the role of the cryosphere in global change. Time-lapse movies of recent changes at Columbia Glacier will be used to engage potential young scientists. A program of presentations outside the university setting to at-risk and gifted youth will be continued. This study will also involve undergraduates in analyses and interpretation and presentation of the seismic data assembled. The work will also support two junior scientists who will be supported by this project.", "east": 72.949097, "geometry": "POINT(72.8836975 -69.008701)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS", "is_usap_dc": false, "keywords": "PASSCAL; Not provided; Antarctic; SEISMOLOGICAL STATIONS; Iceberg; Seismology; Calving", "locations": "Antarctic", "north": -68.993301, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fricker, Helen", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e PASSCAL; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e SEISMOLOGICAL STATIONS; Not provided", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -69.024101, "title": "An Investigation into the Seismic Signatures Generated by Iceberg Calving and Rifting", "uid": "p0000683", "west": 72.818298}, {"awards": "0125172 Gordon, Arnold", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0302; Expedition data of NBP0304C; Expedition data of NBP0304D; Expedition data of NBP0402; Expedition data of NBP0408; Expedition data of NBP0501", "datasets": [{"dataset_uid": "002588", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0302", "url": "https://www.rvdata.us/search/cruise/NBP0302"}, {"dataset_uid": "002620", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0408", "url": "https://www.rvdata.us/search/cruise/NBP0408"}, {"dataset_uid": "002629", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "001692", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304D"}, {"dataset_uid": "001691", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304C"}, {"dataset_uid": "002624", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0304C", "url": "https://www.rvdata.us/search/cruise/NBP0304C"}, {"dataset_uid": "002625", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0304D", "url": "https://www.rvdata.us/search/cruise/NBP0304D"}, {"dataset_uid": "002627", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "002638", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0402", "url": "https://www.rvdata.us/search/cruise/NBP0402"}], "date_created": "Tue, 17 Jan 2012 00:00:00 GMT", "description": "This study will investigate how the Antarctic Slope Front and continental slope morphology determine the exchanges of mass, heat, and fresh water between the shelf and the deep ocean, in particular those leading to outflows of dense water into intermediate and deep layers of the adjacent basins and into the world ocean circulation \u003cbr/\u003eWhile the importance to the global ocean circulation and climate of cold water masses originating in the Antarctic is unquestioned, the processes by which these water masses enter the deep ocean circulation are not. The primary goal of this work therefore is to identify the principal physical processes that govern the transfer of shelf-modified dense water into intermediate and deep layers of the adjacent deep ocean. At the same time, it seeks to understand the compensatory poleward flow of waters from the oceanic regime. The upper continental slope has been identified as the critical gateway for the exchange of shelf and deep ocean waters. Here the topography, velocity and density fields associated with the nearly ubiquitous front must strongly influence the advective and turbulent transfer of water properties between the shelf and oceanic regimes. The study has four specific objectives: [1] Determine the mean frontal structure and the principal scales of variability, and estimate the role of the front on cross-slope exchanges and mixing of adjacent water masses; [2] Determine the influence of slope topography and bathymetry on frontal location and outflow of dense Shelf Water; [3] Establish the role of frontal instabilities, benthic boundary layer transports, tides and other oscillatory processes on cross-slope advection and fluxes; and [4] Assess the effect of diapycnal mixing, lateral mixing identified through intrusions, and nonlinearities in the equation of state on the rate of descent and the fate of outflowing, near-freezing Shelf Water.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Gordon, Arnold; Cande, Steven; Visbeck, Martin; Jacobs, Stanley", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Anslope, Cross-slope Exchanges at the Antarctic Slope Front", "uid": "p0000807", "west": null}, {"awards": "9527571 Whillans, Ian", "bounds_geometry": "POLYGON((158.25 -76.66667,158.325 -76.66667,158.4 -76.66667,158.475 -76.66667,158.55 -76.66667,158.625 -76.66667,158.7 -76.66667,158.775 -76.66667,158.85 -76.66667,158.925 -76.66667,159 -76.66667,159 -76.683336,159 -76.700002,159 -76.716668,159 -76.733334,159 -76.75,159 -76.766666,159 -76.783332,159 -76.799998,159 -76.816664,159 -76.83333,158.925 -76.83333,158.85 -76.83333,158.775 -76.83333,158.7 -76.83333,158.625 -76.83333,158.55 -76.83333,158.475 -76.83333,158.4 -76.83333,158.325 -76.83333,158.25 -76.83333,158.25 -76.816664,158.25 -76.799998,158.25 -76.783332,158.25 -76.766666,158.25 -76.75,158.25 -76.733334,158.25 -76.716668,158.25 -76.700002,158.25 -76.683336,158.25 -76.66667))", "dataset_titles": "GPS Ice Flow Measurements, Allan Hills, Antarctica", "datasets": [{"dataset_uid": "609507", "doi": "10.7265/N5NS0RSX", "keywords": "Allan Hills; Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ice Flow Velocity", "people": "Hamilton, Gordon S.; Spikes, Vandy Blue; Kurbatov, Andrei V.; Spaulding, Nicole", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "GPS Ice Flow Measurements, Allan Hills, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609507"}], "date_created": "Tue, 20 Dec 2011 00:00:00 GMT", "description": "Whillans, Wilson, Goad OPP 9527571 Abstract This award supports a project to initiate Global Positioning System (GPS) measurements for rock motions in South Victoria Land and vicinity. The results will be used to test some of the leading models for ice-sheet change and tectonism, in particular, whether the continent is rebounding due to reduced ice load from East or West Antarctica and whether there is tectonic motion due to Terror Rift or uplift of the Transantarctic Mountains. A modest program to measure ice motion will be conducted as well. The motive is to test models for ice flow in the Allan Hills meteorite concentration region and to determine whether small glaciers in the Dry Valleys are thickening or thinning. Monuments will be set into rock and ice and GPS receivers used to determine their locations. Repeats in later years will determine motion. Field activities will involve close cooperation with the USGS.", "east": 159.0, "geometry": "POINT(158.625 -76.75)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "FIELD SURVEYS; LABORATORY; Not provided; Ice Movement; GPS Data; Vertical Motions; GPS; FIELD INVESTIGATION", "locations": null, "north": -76.66667, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Whillans, Ian; Spaulding, Nicole; Hamilton, Gordon S.; Spikes, Vandy Blue; Kurbatov, Andrei V.", "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": "Allan Hills", "south": -76.83333, "title": "GPS Measurements of Rock and Ice Motions in South Victoria Land", "uid": "p0000523", "west": 158.25}, {"awards": "0636898 Winckler, Gisela", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 30 Nov 2011 00:00:00 GMT", "description": "Winckler/0636898\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to study dust sources in Antarctic ice cores. Atmospheric aerosols play an important role both in global biogeochemical cycles as well as in the climate system of the Earth. Records extracted from Antarctic ice cores inform us that dust deposition from the atmosphere to the ice sheet was 15-20 times greater during glacial periods than during interglacials, which raises the possibility that dust may be a key player in climate change on glacial-interglacial timescales. By characterizing potential source areas from South America, South Africa, and Australia as well as fresh glacial flour from Patagonia, the project will determine if the interglacial dust was mobilized from a distinct geographical region (e.g., Australia) or from a more heavily weathered source region in South America. The intellectual merit of the project is that it will contribute to reconstructing climate-related changes in the rate of dust deposition, and in the provenance of the dust, it will provide critical constraints on hydrology and vegetation in the source regions, as well as on the nature of the atmospheric circulation transporting dust to the archive location. In a recent pilot study it was found that there is a dramatic glacial to Holocene change in the 4He/Ca ratio in the dust extracted from ice from Dronning Maud Land, Antarctica, indicating a shift in the source of dust transported to Antarctica. The broader impacts of the project are that Helium isotopes and calcium measurements provide a wealth of information that can then be turned into critical input for dust-climate models. Improved models, which are able to accurately reconstruct paleo dust distribution, will help us to predict changes in dust in response to future climate variability. This information will contribute to an improvement of our integrated understanding of the Earth\u0027s climate system and, in turn, will better inform policy makers of those processes and conditions most susceptible to perturbation by climate change, thereby leading to more meaningful climate-change policy. The project will support a graduate student in the dual masters Earth and Environmental Science Journalism program. The lead-PI manages the rock noble gas laboratory at Lamont. Her leadership role in this facility impacts the training of undergraduate and graduate students as well as visiting scientists.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": false, "keywords": "Deposition; LABORATORY; Dust; Climate; Not provided; Climate Change; Helium Isotopes; FIELD INVESTIGATION; Biogeochemical Cycles", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Winckler, Gisela", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "Tracing Glacial-interglacial Changes in the Dust Source to Antarctica using Helium Isotopes", "uid": "p0000265", "west": null}, {"awards": "0840979 Adams, Byron; 0840705 Wall, Diana", "bounds_geometry": "POLYGON((165.35155 -83.71592,166.143133 -83.71592,166.934716 -83.71592,167.726299 -83.71592,168.517882 -83.71592,169.309465 -83.71592,170.101048 -83.71592,170.892631 -83.71592,171.684214 -83.71592,172.475797 -83.71592,173.26738 -83.71592,173.26738 -83.894053,173.26738 -84.072186,173.26738 -84.250319,173.26738 -84.428452,173.26738 -84.606585,173.26738 -84.784718,173.26738 -84.962851,173.26738 -85.140984,173.26738 -85.319117,173.26738 -85.49725,172.475797 -85.49725,171.684214 -85.49725,170.892631 -85.49725,170.101048 -85.49725,169.309465 -85.49725,168.517882 -85.49725,167.726299 -85.49725,166.934716 -85.49725,166.143133 -85.49725,165.35155 -85.49725,165.35155 -85.319117,165.35155 -85.140984,165.35155 -84.962851,165.35155 -84.784718,165.35155 -84.606585,165.35155 -84.428452,165.35155 -84.250319,165.35155 -84.072186,165.35155 -83.894053,165.35155 -83.71592))", "dataset_titles": "Genetic Sequences: JN819273 tardsubmission.sqn 354_18S6 JN819274 tardsubmission.sqn 354_ITS JN819275 tardsubmission.sqn 553_18S5_and_18S6 JN819276 tardsubmission.sqn 556_18S6; McMurdo Dry Valleys Long-Term Ecological Research", "datasets": [{"dataset_uid": "000217", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Genetic Sequences: JN819273 tardsubmission.sqn 354_18S6 JN819274 tardsubmission.sqn 354_ITS JN819275 tardsubmission.sqn 553_18S5_and_18S6 JN819276 tardsubmission.sqn 556_18S6", "url": "http://www.ncbi.nlm.nih.gov/genbank/"}, {"dataset_uid": "000157", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "McMurdo Dry Valleys Long-Term Ecological Research", "url": "http://www.mcmlter.org/"}], "date_created": "Mon, 03 Oct 2011 00:00:00 GMT", "description": "Ice sheet models of the Last Glacial Maximum, and previous glaciation events in the Miocene, suggest that current low altitude, ice-free surfaces in Antarctica were completely covered with ice. If so, the terrestrial biota of Antarctica today would result from recolonization events after each glacial maximum. However, there is emerging evidence that much of the terrestrial Antarctic biota are of ancient origin and have somehow survived these glaciation events. The Transantarctic Mountains TRANsition Zone (TAM-TRANZ) plays a pivotal role in understanding the evolution and biogeographic history of today\u0027s Antarctic terrestrial biota, primarily because it contains numerous inland areas that could have served as refugia during glacial maxima. Due to its remote location, the TAM-TRANZ has not been systematically surveyed for animal biodiversity. Although an exhaustive survey of the region requires a multi-discipline, multi-year and multi-region effort, the research herein combines ecological, evolutionary and geophysical expertise to conduct an exploratory investigation of the extreme southern limits of biotic communities. The project will examine the historical geophysical requirements for the colonization and maintenance of functional ecosystems by multicellular organisms, and the feasibility and desirability to implement more systematic biogeographic studies in the future. Broader impacts include graduate and undergraduate student ownership of important subprojects that will provide research, presentation and publication opportunities. The investigators also will contribute to ongoing public education efforts through relationships with K-12 teachers and administrators in the public school districts where the project personnel reside. Finally, the project is leveraged by opportunistic collaboration with scientists associated with Antarctica New Zealand.", "east": 173.26738, "geometry": "POINT(169.309465 -84.606585)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -83.71592, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Adams, Byron; Wall, Diana", "platforms": "Not provided", "repo": "NCBI GenBank", "repositories": "LTER; NCBI GenBank", "science_programs": "LTER", "south": -85.49725, "title": "Collaborative Research: Limits and Drivers of Metazoan Distributions in the Transantarctic Mountains", "uid": "p0000517", "west": 165.35155}, {"awards": "0839084 Ortland, David", "bounds_geometry": "POLYGON((-63 -59,-62 -59,-61 -59,-60 -59,-59 -59,-58 -59,-57 -59,-56 -59,-55 -59,-54 -59,-53 -59,-53 -59.6,-53 -60.2,-53 -60.8,-53 -61.4,-53 -62,-53 -62.6,-53 -63.2,-53 -63.8,-53 -64.4,-53 -65,-54 -65,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-63 -64.4,-63 -63.8,-63 -63.2,-63 -62.6,-63 -62,-63 -61.4,-63 -60.8,-63 -60.2,-63 -59.6,-63 -59))", "dataset_titles": "Large- and Small-scale Dynamics and Meteor Studies in the MLT with a New-generation Meteor Radar on King George Island", "datasets": [{"dataset_uid": "600107", "doi": "10.15784/600107", "keywords": "Antarctica; Atmosphere; Meteorology; Meteor Radar", "people": "Fritts, David; Janches, Diego", "repository": "USAP-DC", "science_program": null, "title": "Large- and Small-scale Dynamics and Meteor Studies in the MLT with a New-generation Meteor Radar on King George Island", "url": "https://www.usap-dc.org/view/dataset/600107"}], "date_created": "Mon, 15 Aug 2011 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The project will employ a sophisticated meteor radar at the Brazilian Antarctic station Comandante Ferraz on King George Island for a number of synergetic research efforts of high interest to the international aeronomical community. The location of the radar will be at the tip of the Antarctic Peninsula - at a critical southern latitude of 62 degrees - to fill a current measurement gap from 54 to 68 degrees south. The radar will play a key role in Antarctic and inter-hemispheric studies of neutral atmosphere dynamics, defining global mesosphere and lower thermosphere structure and variability (from 80 to 105 km) and guiding advances of models accounting for the dynamics of this high-altitude region, including general circulation models, and climate and numerical weather prediction models. The unique radar measurement sensitivity will enable studies of: (1) the large-scale circulation and planetary waves, (2) the tidal structure and variability, (3) the momentum transport by small-scale gravity waves, (4) important, but unquantified, gravity wave - tidal interactions, (5) polar mesosphere summer echoes, and (6) meteor fluxes, head echoes, and non-specular trails, a number of which exhibit high latitudinal gradients at these latitudes. This radar will support extensive collaborations with U.S. and other scientists making measurements at other Antarctic and Arctic conjugate sites, including Brazilian scientists at C. Ferraz and U.S. and international colleagues having other instrumentation in the Antarctic, Arctic, and within South America. Links to the University of Colorado in the U.S., Instituto Nacional de Pesquisas Espaciais (INPE) in Brazil and Universidad Nacional de La Plata in Argentina will provide unique research opportunities for graduate and undergraduate students in the U.S. and South America.", "east": -53.0, "geometry": "POINT(-58 -62)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -59.0, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Fritts, David; Janches, Diego", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Large- and Small-scale Dynamics and Meteor Studies in the MLT with a New-generation Meteor Radar on King George Island", "uid": "p0000670", "west": -63.0}, {"awards": "0636719 Joughin, Ian; 0636970 Tulaczyk, Slawek", "bounds_geometry": null, "dataset_titles": "Antarctic Active Subglacial Lake Inventory from ICESat Altimetry", "datasets": [{"dataset_uid": "601439", "doi": "10.15784/601439", "keywords": "Altimetry; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Icesat; Laser Altimetry; Subglacial Lake", "people": "Fricker, Helen; Smith, Ben; Joughin, Ian; Tulaczyk, Slawek", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Active Subglacial Lake Inventory from ICESat Altimetry", "url": "https://www.usap-dc.org/view/dataset/601439"}], "date_created": "Wed, 27 Jul 2011 00:00:00 GMT", "description": "Tulaczyk/0636970\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to study elevation change anomalies (henceforth ECAs), which are oval-shaped, 5-to-10 km areas observed in remote sensing images in several locations within the Ross Sea sector of the West Antarctic Ice Sheet (WAIS). Within these anomalies, surface elevation changes at rates of up to ~1 to ~2 cm per day, significantly faster than in surrounding regions. These anomalies are thought to result from filling and draining of multi-kilometer-scale subglacial water pockets. The intellectual merit of this project is that these ECA\u0027s represent an unprecedented window into the elusive world of water drainage dynamics beneath the modern Antarctic ice sheet. Although subglacial water fluxes are small compared to normal terrestrial conditions, they play an important role in controlling fast ice streaming and, potentially, stability of the ice sheet. The dearth of observational constraints on sub-ice sheet water dynamics represents one of the most important limitations on progress in quantitative modeling of ice streams and ice sheets. Such models are necessary to assess future ice sheet mass balance and to reconstruct the response of ice sheets to past climate changes. The dynamic sub-ice sheet water transport indicated by the ECAs may have also implications for studies of subglacial lakes and other subglacial environments, which may harbor life adapted to such extreme conditions. The broader impacts of this project are that it will provide advanced training opportunities to one postdoctoral fellow (UW), two female doctoral students (UCSC), who will enhance diversity in polar sciences, and at least three undergraduate students (UCSC). Project output will be relevant to broad scientific and societal interests, such as the future global sea level changes and the response of Polar Regions to climate changes. Douglas Fox, a freelance science journalist, is interested in joining the first field season to write feature articles to popular science magazines and promote the exposure of this project, and Antarctic Science in general, to mass media.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e LIDAR/LASER ALTIMETERS \u003e GLAS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e LIDAR/LASER ALTIMETERS \u003e GLAS", "is_usap_dc": false, "keywords": "ICESAT; Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Smith, Ben; Joughin, Ian; Tulaczyk, Slawek; SMITH, BENJAMIN", "platforms": "Not provided; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e ICE, CLOUD AND LAND ELEVATION SATELLITE (ICESAT) \u003e ICESAT", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Elevation Change Anomalies in West Antarctica and Dynamics of Subglacial Water Transport Beneath Ice Streams and their Tributaries", "uid": "p0000115", "west": null}, {"awards": "0902957 Robinson, Laura", "bounds_geometry": "POLYGON((-70.5 -54.5,-66.95 -54.5,-63.4 -54.5,-59.85 -54.5,-56.3 -54.5,-52.75 -54.5,-49.2 -54.5,-45.65 -54.5,-42.1 -54.5,-38.55 -54.5,-35 -54.5,-35 -55.2,-35 -55.9,-35 -56.6,-35 -57.3,-35 -58,-35 -58.7,-35 -59.4,-35 -60.1,-35 -60.8,-35 -61.5,-38.55 -61.5,-42.1 -61.5,-45.65 -61.5,-49.2 -61.5,-52.75 -61.5,-56.3 -61.5,-59.85 -61.5,-63.4 -61.5,-66.95 -61.5,-70.5 -61.5,-70.5 -60.8,-70.5 -60.1,-70.5 -59.4,-70.5 -58.7,-70.5 -58,-70.5 -57.3,-70.5 -56.6,-70.5 -55.9,-70.5 -55.2,-70.5 -54.5))", "dataset_titles": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals", "datasets": [{"dataset_uid": "600111", "doi": "10.15784/600111", "keywords": "Biota; Corals; Drake Passage; Geochronology; NBP0805; Oceans; Paleoclimate; Radiocarbon; Southern Ocean", "people": "Robinson, Laura", "repository": "USAP-DC", "science_program": null, "title": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals", "url": "https://www.usap-dc.org/view/dataset/600111"}], "date_created": "Tue, 28 Jun 2011 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The proposal seeks funds to continue a follow-up analytical work of deep-sea corals collected in the Drake Passage during a research cruise. The project\u0027s goal is paleo-climate research looking to constrain the depth structure and time evolution of the radiocarbon content of the Southern Ocean during the glacial and deglaciation. Radiocarbon is a versatile tracer of past climate; its radioactive decay provides an internal clock with which to assess the rates of processes, and it can be used to trace the movement of carbon through the Earth\u0027s system. It enters the ocean through air-sea gas exchange, so processes that limits this will, therefore, reduce the radiocarbon content of both surface and deep waters. The Southern Ocean is a critical location for exchange of heat and carbon between the deep-ocean and atmospheric reservoirs, and the deep waters formed there fill large volumes of the global deep and intermediate oceans. As strong currents tend to scour away sediments, carbonate preservation is limited, and radiocarbon reservoir ages are poorly constrained, many traditional paleoceanographic techniques become impractical. It is proposed to alleviate these difficulties analyzing the chemical composition of deep-sea coral skeletons. Their aragonitic skeletons can be precisely dated using U-series decay, and when coupled with radiocarbon analyses will allow to calculate the C14/C12 ratio of the past water column.", "east": -35.0, "geometry": "POINT(-52.75 -58)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -54.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Robinson, Laura", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -61.5, "title": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals", "uid": "p0000519", "west": -70.5}, {"awards": "9909734 Anderson, John", "bounds_geometry": "POLYGON((-73.80311 -52.35021,-71.817373 -52.35021,-69.831636 -52.35021,-67.845899 -52.35021,-65.860162 -52.35021,-63.874425 -52.35021,-61.888688 -52.35021,-59.902951 -52.35021,-57.917214 -52.35021,-55.931477 -52.35021,-53.94574 -52.35021,-53.94574 -53.954842,-53.94574 -55.559474,-53.94574 -57.164106,-53.94574 -58.768738,-53.94574 -60.37337,-53.94574 -61.978002,-53.94574 -63.582634,-53.94574 -65.187266,-53.94574 -66.791898,-53.94574 -68.39653,-55.931477 -68.39653,-57.917214 -68.39653,-59.902951 -68.39653,-61.888688 -68.39653,-63.874425 -68.39653,-65.860162 -68.39653,-67.845899 -68.39653,-69.831636 -68.39653,-71.817373 -68.39653,-73.80311 -68.39653,-73.80311 -66.791898,-73.80311 -65.187266,-73.80311 -63.582634,-73.80311 -61.978002,-73.80311 -60.37337,-73.80311 -58.768738,-73.80311 -57.164106,-73.80311 -55.559474,-73.80311 -53.954842,-73.80311 -52.35021))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001803", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0201"}], "date_created": "Thu, 03 Mar 2011 00:00:00 GMT", "description": "9909734 Anderson This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research on the glaciomarine geology of the continental shelves of West Antarctica and the Antarctic Peninsula. It is hypothesized that the different glacial systems of the Antarctic Peninsula region have been more responsive to climate change and sea-level rise than either the West Antarctic or East Antarctic ice sheets. This is due mainly to the smaller size of these ice masses and the higher latitude location of the peninsula. Indeed, ice shelves of the Antarctic Peninsula are currently retreating at rates of up to a kilometer per year. But are these changes due to recent atmospheric warming in the region or are they simply the final phase of retreat since the last glacial maximum? This project hypothesizes that the deglacial history of the Antarctic Peninsula region has been quite complex, with different glacial systems retreating at different rates and at different times. This complex recessional history reflects the different sizes as well as different climatic and physiographic settings of glacial systems in the region. An understanding of the Late Pleistocene to Holocene glacial history of the Antarctic Peninsula glacial systems is needed to address how these systems responded to sea-level and climate change during that time interval. This investigation acquire new marine geological and geophysical data from the continental shelf to determine if and when different glacial systems were grounded on the shelf, to establish the extent of grounded ice, and to examine the history of glacial retreat. The project will build on an extensive seismic data set and hundreds of sediment cores collected along the Peninsula during earlier (1980\u0027s) cruises. Key to this investigation is the acquisition of swath bathymetry, side-scan sonar and very high-resolution sub-bottom (chirp) profiles from key drainage outlets. These new data will provide the necessary geomorphologic and stratigraphic framework for reconstructing the Antarctic Peninsula glacial record. Anticipated results will help constrain models for future glacier and ice sheet activity.", "east": -53.94574, "geometry": "POINT(-63.874425 -60.37337)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.35021, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, John; Anderson, Jason", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -68.39653, "title": "LGM Late Pleistocene to Holocene Glacial History of West Antarctica", "uid": "p0000600", "west": -73.80311}, {"awards": "0732535 Arrigo, Kevin", "bounds_geometry": "POLYGON((-130 -67,-127.1 -67,-124.2 -67,-121.3 -67,-118.4 -67,-115.5 -67,-112.6 -67,-109.7 -67,-106.8 -67,-103.9 -67,-101 -67,-101 -67.9,-101 -68.8,-101 -69.7,-101 -70.6,-101 -71.5,-101 -72.4,-101 -73.3,-101 -74.2,-101 -75.1,-101 -76,-103.9 -76,-106.8 -76,-109.7 -76,-112.6 -76,-115.5 -76,-118.4 -76,-121.3 -76,-124.2 -76,-127.1 -76,-130 -76,-130 -75.1,-130 -74.2,-130 -73.3,-130 -72.4,-130 -71.5,-130 -70.6,-130 -69.7,-130 -68.8,-130 -67.9,-130 -67))", "dataset_titles": "GEOTRACES International Data Assembly Centre Accession# NIO100280", "datasets": [{"dataset_uid": "000212", "doi": "", "keywords": null, "people": null, "repository": "GEOTRACES", "science_program": null, "title": "GEOTRACES International Data Assembly Centre Accession# NIO100280", "url": "http://www.bodc.ac.uk/geotraces/"}], "date_created": "Thu, 24 Feb 2011 00:00:00 GMT", "description": "IPY: Shedding dynamic light on iron limitation: The interplay of iron\u003cbr/\u003elimitation and dynamic irradiance in governing the phytoplankton\u003cbr/\u003edistribution in the Ross Sea\u003cbr/\u003e\u003cbr/\u003eThe Southern Ocean plays an important role in the global carbon cycle, accounting for approximately 25% of total anthropogenic CO2 uptake by the oceans, mainly via primary production. In the Ross Sea, primary production is dominated by two taxa that are distinct in location and timing. Diatoms dominate in the shallow mixed layer of the continental shelf, whereas the colony forming Phaeocystis antarctica (Prymnesiophyceae) dominate in the more deeply mixed, open regions. Significantly, both groups have vastly different nutrient utilization characteristics, and support very different marine food webs. Their responses to climate change, and the implications for carbon export, are unclear. Previous studies show that light availability and the quality of the light climate (static versus dynamic) play a major role in defining where and when the different phytoplankton taxa bloom. However, iron (Fe) limitation of the algal communities in both the sub-Arctic and the Southern Ocean is now well documented. Moreover, phytoplankton Fe demand varies as a function of irradiance. The main hypothesis of the proposed research is: The interaction between Fe limitation and dynamic irradiance governs phytoplankton distributions in the Ross Sea. Our strategy to test this hypothesis is three-fold: 1) The photoacclimation of the different phytoplankton taxa to different light conditions under Fe limitation will be investigated in experiments in the laboratory under controlled Fe conditions. 2) The photophysiological mechanisms found in these laboratory experiments will then be tested in the field on two cruises with international IPY partners. 3) Finally, data generated during the lab and field parts of the project will be used to parameterize a dynamic light component of the Coupled Ice Atmosphere and Ocean (CIAO) model of the Ross Sea. Using the improved model, we will run future climate scenarios to test the impact of climate change on the phytoplankton community structure, distribution, primary production and carbon export in the Southern Ocean. The proposed research complies with IPY theme\" Understanding Environmental change in Polar Regions\" and includes participation in an international cruise. Detailed model descriptions and all of the results generated from these studies will be made public via a DynaLiFe website. Improving the CIAO model will give us and other IPY partners the opportunity to test the ecological consequences of physiological characteristics observed in Antarctic phytoplankton under current and future climate scenarios. Outreach will include participation in Stanford\u0027s Summer Program for Professional Development for Science Teachers, Stanford\u0027s School of Earth Sciences high school internship program, and development of curriculum for local science training centers, including the Chabot Space and Science Center.", "east": -101.0, "geometry": "POINT(-115.5 -71.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -67.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Arrigo, Kevin", "platforms": "Not provided", "repo": "GEOTRACES", "repositories": "GEOTRACES", "science_programs": null, "south": -76.0, "title": "IPY: Shedding dynamic light on iron limitation: The interplay of iron limitation and dynamic irradiance in governing the phytoplankton distribution in the Ross Sea", "uid": "p0000112", "west": -130.0}, {"awards": "0840733 Murr, 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": null, "datasets": null, "date_created": "Fri, 30 Jul 2010 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The overall goal of this project is to increase understanding of the conjugate nature of the polar ionospheres, which in part helps understanding the multi-scale global solar wind, magnetosphere, and ionosphere system. The project utilizes numerous types of ionospheric remote sensing instrumentation, including: terrestrial GPS receivers, GPS satellite occultation receivers, all-sky imagers, riometers, and magnetometers currently deployed in the Arctic and Antarctic to estimate the 3-D time histories of the ionospheric electron density and also to estimate the polar wind in these polar regions. Furthermore, additional GPS instrumentation will be deployed in Antarctica to increase the number and improve the spatial distribution of GPS receivers in this region. Import aspects of this investigation are: (1) utilization of a large array of instrumentation in the Arctic and Antarctic regions to provide the maximum number of measurements of the ionosphere, (2) the modification and deployment of commercial-off-the-shelf GPS receivers in remote Antarctic locations to improve spatial distribution of GPS measurements, (3) development of a new estimation algorithm for estimating the polar wind, and (4) estimation of 3-D electron density time histories and conductances in conjugate polar ionospheres. The fieldwork and analysis efforts associated with this project are highly suitable for involvement and research training of graduate and undergraduate students.", "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": null, "paleo_time": null, "persons": "Murr, David", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Imaging, Estimation, and Analysis of Density Distributions in the Conjugate Polar Ionospheres", "uid": "p0000671", "west": -180.0}, {"awards": "0538494 Meese, Debra", "bounds_geometry": null, "dataset_titles": "Microstructural Location and Composition of Impurities in Polar Ice Cores", "datasets": [{"dataset_uid": "609436", "doi": "10.7265/N5DF6P5P", "keywords": "Antarctica; Arctic; Byrd Glacier; Byrd Ice Core; Chemistry:ice; Chemistry:Ice; Geochemistry; GISP2; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Lake Vostok; Paleoclimate; Vostok Ice Core", "people": "Baker, Ian; Obbard, Rachel", "repository": "USAP-DC", "science_program": null, "title": "Microstructural Location and Composition of Impurities in Polar Ice Cores", "url": "https://www.usap-dc.org/view/dataset/609436"}], "date_created": "Thu, 03 Jun 2010 00:00:00 GMT", "description": "0538494\u003cbr/\u003eMeese\u003cbr/\u003eThis award supports a project for physical properties research on snow pits and firn/ice cores with specific objectives that include stratigraphic analysis including determination of accumulation rates, annual layers, depth hoar, ice and wind crusts and rates of grain growth with depth. Studies of firn densification rates and how these parameters relate to the meteorology and climatology over the last 200 years of snow accumulation in Antarctica will also be investigated. The project will also determine the seasonality of accumulation by co-registration of stratigraphy and chemistry and determination of chemical species at the grain boundaries, how these may change with depth/densification (and therefore temperature), precipitation, and may affect grain growth. Fabric analyses will be made, including variation with depth, location on undulations and if any variation exists with climate/chemistry. The large spatial coverage of the US ITASE program offers the opportunity to determine how these parameters are affected by a large range of temperature, precipitation and topographic effects. The intellectual merit of the project includes the fact that ITASE is the terrestrial equivalent of a polar research vessel that provides a unique, logistically efficient, multi-dimensional (x, y, z and time) view of the atmosphere, ice sheet and their histories. Physical properties measurements/ analyses are an integral part of understanding the dynamic processes to which the accumulated snow is subjected. Recent advancements in the field along with multiple core sites provide an excellent opportunity to gain a much broader understanding of the spatial, temporal and physical variables that impact firnification and the possible resultant impact on climatic interpretation. In terms of broader impacts, the data collected by US ITASE and its international ITASE partners is available to a broad scientific community. US ITASE has an extensive program of public outreach and provides significant opportunities for many students to experience multidisciplinary Antarctic research. A graduate student, a post-doctoral fellow and at least one undergraduate would be funded by this work. Dr. Meese is also a member of the New England Science Collaborative, an organization that educates the public on climate change based on recent scientific advancements.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e SCANNING ELECTRON MICROSCOPES", "is_usap_dc": false, "keywords": "LABORATORY; Grain Growth; FIELD SURVEYS; Accumulation Rate; Firn Core; FIELD INVESTIGATION; Chemistry; Snow Pit; Depth Hoar; Firn Density; Ice Core; Not provided; Stratigraphic Analysis; Firn; US ITASE; Annual Layers", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Meese, Deb; MEESE, DEBRA", "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": null, "title": "The Physical Properties of the US ITASE Firn and Ice Cores from South Pole to Taylor Dome", "uid": "p0000289", "west": null}, {"awards": "0636696 DeVries, Arthur", "bounds_geometry": "POLYGON((-68.0025 -52.7599,-67.07254 -52.7599,-66.14258 -52.7599,-65.21262 -52.7599,-64.28266 -52.7599,-63.3527 -52.7599,-62.42274 -52.7599,-61.49278 -52.7599,-60.56282 -52.7599,-59.63286 -52.7599,-58.7029 -52.7599,-58.7029 -53.98242,-58.7029 -55.20494,-58.7029 -56.42746,-58.7029 -57.64998,-58.7029 -58.8725,-58.7029 -60.09502,-58.7029 -61.31754,-58.7029 -62.54006,-58.7029 -63.76258,-58.7029 -64.9851,-59.63286 -64.9851,-60.56282 -64.9851,-61.49278 -64.9851,-62.42274 -64.9851,-63.3527 -64.9851,-64.28266 -64.9851,-65.21262 -64.9851,-66.14258 -64.9851,-67.07254 -64.9851,-68.0025 -64.9851,-68.0025 -63.76258,-68.0025 -62.54006,-68.0025 -61.31754,-68.0025 -60.09502,-68.0025 -58.8725,-68.0025 -57.64998,-68.0025 -56.42746,-68.0025 -55.20494,-68.0025 -53.98242,-68.0025 -52.7599))", "dataset_titles": "Expedition Data; Expedition data of LMG0809; Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae)", "datasets": [{"dataset_uid": "601811", "doi": null, "keywords": "Antarctica; Bellingshausen Sea; Cryosphere; Southern Ocean", "people": "Biesack, Ellen; Corso, Andrew; Desvignes, Thomas; McDowell, Jan; Cheng, Chi-Hing; Steinberg, Deborah; Hilton, Eric", "repository": "USAP-DC", "science_program": "LTER", "title": "Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae)", "url": "https://www.usap-dc.org/view/dataset/601811"}, {"dataset_uid": "002728", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0809", "url": "https://www.rvdata.us/search/cruise/LMG0809"}, {"dataset_uid": "001493", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0810"}, {"dataset_uid": "001504", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0809"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Antarctic notothenioid fish evolved antifreeze (AF) proteins that prevent ice crystals that enter their body fluids from growing, and thereby avoid freezing in their icy habitats. However, even in the extreme cold Antarctic marine environment, regional gradations of severity are found. The biological correlate for environmental severity in fish is the endogenous ice load, which likely determines the tolerable limit of environmental severity for notothenioid habitation. The endogenous ice load develops from environmental ice crystals entering through body surfaces and somehow localizing to the spleen. How prone the surface tissues are to ice entry, how ice reaches the spleen, and what the fate of splenic ice is, requires elucidation. Spleen sequestration of ice raises the hypothesis that macrophages may play a role in the translocation and perhaps elimination of AF-bound ice crystals. Antifreeze glycoproteins (AFGP) act in concert with a second, recently discovered antifreeze called antifreeze potentiating protein (AFPP), necessitating an assessment of the contribution of AFPP to freezing avoidance. Recent research suggests that the exocrine pancreas and the anterior stomach, not the liver, synthesize AFGPs and secrete them into the intestine, from where they may be returned to the blood. A GI-to-blood transport is a highly unconventional path for a major plasma protein and also begs the questions, What is the source of blood AFPP?. Why are two distinct AF proteins needed and what is the chronology of their evolution? What genomic changes in the DNA are associated with the development or loss of the antifreeze trait? Experiments described in this proposal address these interrelated questions of environmental, organismal, and evolutionary physiology, and will further our understanding of novel vertebrate physiologies, the limits of environmental adaptation, and climatically driven changes in the genome. The proposed research will (1) determine the temporal and spatial heterogeneity of environmental temperature and iciness in progressively more severe fish habitats in the greater McMurdo Sound area, and in the milder Arthur Harbor at Palmer Station. The splenic ice load in fishes inhabiting these sites will be determined to correlate to environmental severity and habitability. (2) Assess the surface tissue site of ice entry and their relative barrier properties in intact fish and isolated tissues preparations (3) Assess the role of immune cells in the fate of endogenous ice, (4) determine whether the blood AFGPs are from intestinal/rectal uptake, (5) examine the contribution of AFPP to the total blood AF activity (6) evaluate the progression of genomic changes in the AFGP locus across Notothenioidei as modulated by disparate thermal environments, in four selected species through the analyses of large insert DNA BAC clones. The origin and evolution of AFPP will be examined also by analyzing BAC clones encompassing the AFPP genomic locus. The broader impacts of the proposed research include training of graduate and undergraduate students in research approaches ranging from physical field measurements to cutting edge genomics. Undergraduate research projects have lead to co-authored publications and will continue to do so. Outreach includes establishing Wiki websites on topics of Antarctic fish biology and freeze avoidance, providing advisory services to the San Francisco Science Exploratorium, and making BAC libraries available to interested polar biologists. This research theme has repeatedly received national and international science news coverage and will continue to be disseminated to the public in that manner.", "east": -58.7029, "geometry": "POINT(-63.3527 -58.8725)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.7599, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Devries, Arthur", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -64.9851, "title": "Environmental, Organismal and Evolutionary Physiology of Freeze Avoidance in Antarctic Notothenioid Fishes", "uid": "p0000560", "west": -68.0025}, {"awards": "0338290 Kremer, Patricia; 0338090 Madin, Laurence", "bounds_geometry": "POLYGON((-69.9083 -52.7624,-68.96368 -52.7624,-68.01906 -52.7624,-67.07444 -52.7624,-66.12982 -52.7624,-65.1852 -52.7624,-64.24058 -52.7624,-63.29596 -52.7624,-62.35134 -52.7624,-61.40672 -52.7624,-60.4621 -52.7624,-60.4621 -54.01423,-60.4621 -55.26606,-60.4621 -56.51789,-60.4621 -57.76972,-60.4621 -59.02155,-60.4621 -60.27338,-60.4621 -61.52521,-60.4621 -62.77704,-60.4621 -64.02887,-60.4621 -65.2807,-61.40672 -65.2807,-62.35134 -65.2807,-63.29596 -65.2807,-64.24058 -65.2807,-65.1852 -65.2807,-66.12982 -65.2807,-67.07444 -65.2807,-68.01906 -65.2807,-68.96368 -65.2807,-69.9083 -65.2807,-69.9083 -64.02887,-69.9083 -62.77704,-69.9083 -61.52521,-69.9083 -60.27338,-69.9083 -59.02155,-69.9083 -57.76972,-69.9083 -56.51789,-69.9083 -55.26606,-69.9083 -54.01423,-69.9083 -52.7624))", "dataset_titles": "Data at U.S. JGOFS Data System; Expedition Data", "datasets": [{"dataset_uid": "000118", "doi": "", "keywords": null, "people": null, "repository": "JGOF", "science_program": null, "title": "Data at U.S. JGOFS Data System", "url": "http://usjgofs.whoi.edu/jg/dir/jgofs/"}, {"dataset_uid": "001573", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0602"}, {"dataset_uid": "001565", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0414"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Salps are planktonic grazers that have a life history, feeding biology and population dynamic strikingly different from krill, copepods or other crustacean zooplankton. Salps can occur in very dense population blooms that cover large areas and have been shown to have major impacts due to the their grazing and the production of fast-sinking fecal pellets. Although commonly acknowledged as a major component of the Southern Ocean zooplankton community, often comparable in biomass and distribution to krill, salps have received relatively little attention. Although extensive sampling has documented the seasonal abundance of salps in the Southern Ocean, there is a paucity of data on important rates that determine population growth and the role of this species in grazing and vertical flux of particulates. This proposed study will include: measurements of respiration and excretion rates for solitary and aggregate salps of all sizes; measurements of ingestion rates, including experiments to determine the size or concentration of particulates that can reduce ingestion; and determination of growth rates of solitaries and aggregates. In addition to the various rate measurements, this study will include quantitative surveys of salp horizontal and vertical distribution to determine their biomass and spatial distribution, and to allow a regional assessment of their effects. Measurements of the physical characteristics of the water column and the quantity and quality of particulate food available for the salps at each location will also be made. Satellite imagery and information on sea-ice cover will be used to test hypotheses about conditions that result in high densities of salps. Results will be used to construct a model of salp population dynamics, and both experimental and modeling results will be interpreted within the context of the physical and nutritional conditions to which the salps are exposed. This integrated approach will provide a good basis for understanding the growth dynamics of salp blooms in the Southern Ocean. Two graduate students will be trained on this project, and cruise and research experience will be provided for two undergraduate students. A portion of a website allowing students to be a virtual participant in the research will be created to strengthen students\u0027 quantitative skills. Both PI\u0027s will participate in teacher-researcher workshops, and collaboration with a regional aquarium will be developed in support of public education.", "east": -60.4621, "geometry": "POINT(-65.1852 -59.02155)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": true, "keywords": "Not provided; R/V LMG", "locations": null, "north": -52.7624, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kremer, Patricia; Madin, Larry; Halanych, Kenneth", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "JGOF", "repositories": "JGOF; R2R", "science_programs": null, "south": -65.2807, "title": "Collaborative Research: Salpa Thompsoni in the Southern Ocean: Bioenergetics, Population Dynamics and Biogeochemical Impact", "uid": "p0000227", "west": -69.9083}, {"awards": "0125624 Wilson, Terry; 0126279 Lawver, Lawrence", "bounds_geometry": "POLYGON((163.69456 -75.04911,164.525266 -75.04911,165.355972 -75.04911,166.186678 -75.04911,167.017384 -75.04911,167.84809 -75.04911,168.678796 -75.04911,169.509502 -75.04911,170.340208 -75.04911,171.170914 -75.04911,172.00162 -75.04911,172.00162 -75.3293,172.00162 -75.60949,172.00162 -75.88968,172.00162 -76.16987,172.00162 -76.45006,172.00162 -76.73025,172.00162 -77.01044,172.00162 -77.29063,172.00162 -77.57082,172.00162 -77.85101,171.170914 -77.85101,170.340208 -77.85101,169.509502 -77.85101,168.678796 -77.85101,167.84809 -77.85101,167.017384 -77.85101,166.186678 -77.85101,165.355972 -77.85101,164.525266 -77.85101,163.69456 -77.85101,163.69456 -77.57082,163.69456 -77.29063,163.69456 -77.01044,163.69456 -76.73025,163.69456 -76.45006,163.69456 -76.16987,163.69456 -75.88968,163.69456 -75.60949,163.69456 -75.3293,163.69456 -75.04911))", "dataset_titles": "Expedition Data; NBP0401 data", "datasets": [{"dataset_uid": "000106", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0401 data", "url": "https://www.rvdata.us/search/cruise/NBP0401"}, {"dataset_uid": "001664", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0401"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a study to investigate the tectonic development of the southwestern Ross Sea region. Displacements between East and West Antarctica have long been proposed based on global plate circuits, apparent hot spot motions, interpretations of seafloor magnetic anomalies, paleomagnetism, and on geologic grounds. Such motions require plate boundaries crossing Antarctica, yet these boundaries have never been explicitly defined. This project will attempt to delineate the late Cenozoic - active boundary between East and West Antarctica along the Terror Rift in the western Ross Sea, where young structures have been identified, continuity between active extension and intracontinental structures can be established, and where accessibility via ship will allow new key data sets to be acquired. We will use multi-source marine and airborne geophysical data to map the fault patterns and volcanic structure along the eastern margin of the Terror Rift. The orientations of volcanic fissures and seamount alignments on the seafloor will be mapped using multibeam bathymetry. The volcanic alignments will show the regional extension or shear directions across the Terror Rift and the orientations of associated crustal stresses. Swath bathymetry and single channel seismic data will be used to document neotectonic fault patterns and the eastern limit of recent faulting. Delineation of neotectonic fault patterns will demonstrate whether the eastern margin of the Terror Rift forms a continuous boundary and whether the rift itself can be linked with postulated strike-slip faults in the northwestern Ross Sea. Seafloor findings from this project will be combined with fault kinematic and stress field determinations from the surrounding volcanic islands and the Transantarctic Mountains. The integrated results will test the propositions that the eastern boundary of the Terror Rift forms the limit of the major, late Cenozoic -active structures through the Ross Sea and that Terror Rift kinematics involve dextral transtension linked to the right-lateral strike-slip faulting to the north. These results will help constrain the kinematic and dynamic links between the West Antarctic rift system and Southern Ocean structures and any related motions between East and West Antarctica. In the first year, a collaborative structural analysis of existing multichannel and single channel seismic profiles and aeromagnetic data over the Terror Rift will be conducted. The location of volcanic vents or fissures and any fault scarps on the sea floor will be identified and a preliminary interpretation of the age and kinematics of deformation in the Terror Rift will be produced. Late in the second year, a one-month cruise on RVIB N.B. Palmer will carry out multibeam bathymetric and sidescan sonar mapping of selected portions of the seafloor of Terror Rift. Gravity, magnetics, seismic reflection and Bathy2000 3.5 kHz sub-bottom profile data will also be collected across the rift. In the third year, we will use these multisource data to map the orientations and forms of volcanic bodies and the extent and geometry of neotectonic faulting associated with the Terror Rift. The project will: 1) complete a map of neotectonic faults and volcanic structures in the Terror Rift; 2) interpret the structural pattern to derive the motions and stresses associated with development of the rift; 3) compare Terror Rift structures with faults and lineaments mapped in the Transantarctic Mountains to improve age constraints on the structures; and 4) integrate the late Cenozoic structural interpretations from the western Ross Sea with Southern Ocean plate boundary kinematics.", "east": 172.00162, "geometry": "POINT(167.84809 -76.45006)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": true, "keywords": "R/V NBP", "locations": null, "north": -75.04911, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Wilson, Terry", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.85101, "title": "Collaborative Research: Neotectonic Structure of Terror Rift, Western Ross Sea", "uid": "p0000111", "west": 163.69456}, {"awards": "0538516 Ackley, Stephen", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0709", "datasets": [{"dataset_uid": "002648", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0709", "url": "https://www.rvdata.us/search/cruise/NBP0709"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is a study of the evolution of the sea ice cover, and the mass balance of ice in the Amundsen Sea and the Bellingshausen Sea in the internationally collaborative context of the International Polar Year (2007-2008). In its simplest terms, the mass balance is the net freezing and melting that occurs over an annual cycle at a given location. If the ice were stationary and were completely to melt every year, the mass balance would be zero. While non-zero balances have significance in questions of climate and environmental change, the process itself has global consequences since the seasonal freeze-melt cycle has the effect of distilling the surface water. Oceanic salt is concentrated into brine and rejected from the ice into deeper layers in the freezing process, while during melt, the newly released and relatively fresh water stabilizes the surface layers. The observation program will be carried out during a drift program of the Nathaniel B. Palmer, and through a buoy network established on the sea ice that will make year-long measurements of ice thickness, and temperature profile, large-scale deformation, and other characteristics. The project is a component of the Antarctic Sea Ice Program, endorsed internationally by the Joint Committee for IPY. Additionally, the buoys to be deployed have been endorsed as an IPY contribution to the World Climate Research Program/Scientific Committee on Antarctic Research (WCRP/SCAR) International Programme on Antarctic Buoys (IPAB). While prior survey information has been obtained in this region, seasonal and time-series measurements on sea ice mass balance are crucial data in interpreting the mechanisms of air-ice-ocean interaction. \u003cbr/\u003e The network will consist of an array of twelve buoys capable of GPS positioning. Three buoys will be equipped with thermister strings and ice and snow thickness measurement gauges, as well as a barometer. Two buoys will be equipped with meteorological sensors including wind speed and direction, atmospheric pressure, and incoming radiation. Seven additional buoys will have GPS positioning only, and will be deployed approximately 100 km from the central site. These outer buoys will be critical in capturing high frequency motion complementary to satellite-derived ice motion products. Additional buoys have been committed internationally through IPAB and will be deployed in the region as part of this program.\u003cbr/\u003e This project will complement similar projects to be carried out in the Weddell Sea by the German Antarctic Program, and around East Antarctica by the Australian Antarctic Program. The combined buoy and satellite deformation measurements, together with the mass balance measurements, will provide a comprehensive annual data set on sea ice thermodynamics and dynamics for comparison with both coupled and high-resolution sea ice models.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Ackley, Stephen", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Sea Ice Mass Balance in the Antarctic-SIMBA Drift Station", "uid": "p0000839", "west": null}, {"awards": "9220848 Bartek, Louis", "bounds_geometry": "POLYGON((-179.9996 -52.35472,-143.99968 -52.35472,-107.99976 -52.35472,-71.99984 -52.35472,-35.99992 -52.35472,0 -52.35472,35.99992 -52.35472,71.99984 -52.35472,107.99976 -52.35472,143.99968 -52.35472,179.9996 -52.35472,179.9996 -54.916322,179.9996 -57.477924,179.9996 -60.039526,179.9996 -62.601128,179.9996 -65.16273,179.9996 -67.724332,179.9996 -70.285934,179.9996 -72.847536,179.9996 -75.409138,179.9996 -77.97074,143.99968 -77.97074,107.99976 -77.97074,71.99984 -77.97074,35.99992 -77.97074,0 -77.97074,-35.99992 -77.97074,-71.99984 -77.97074,-107.99976 -77.97074,-143.99968 -77.97074,-179.9996 -77.97074,-179.9996 -75.409138,-179.9996 -72.847536,-179.9996 -70.285934,-179.9996 -67.724332,-179.9996 -65.16273,-179.9996 -62.601128,-179.9996 -60.039526,-179.9996 -57.477924,-179.9996 -54.916322,-179.9996 -52.35472))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002245", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9407"}, {"dataset_uid": "002265", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9307"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award supports an integrated seismic, sedimentologic, and paleontologic investigation of glacio-marine stratigraphy of the Ross Sea continental shelf. The purpose of this work is to acquire seismic images and sediment cores of the glacial sediments toward a better understanding of the Cenozoic history of glaciation in the Ross Sea region. This investigation will utilize high resolution seismic profiling data to locate regions where the Pleistocene glacial till is thin or perhaps absent. Piston coring at these locations, if the till is penetrated, will provide sedimentary records of Cenozoic depositional environments and could provide important clues to fluctuations of the Antarctic Ice Sheets. The seismic profiling will provide a direct record of the grounding history of the Ross Ice Shelf during the Pleistocene and it will also allow first order correlations of Cenozoic sedimentary units that are represented by sediments recovered in the piston cores. This work will provide important proxy records of the history of both the West Antarctic Ice Sheet and the East Antarctic Ice Sheet and this, in turn, will provide important constraints to climate models.", "east": 179.9996, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.35472, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Bartek, Louis", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.97074, "title": "Integrated Biostratigraphy and High Resolution Seismic Stratigraphy of the Ross Sea: Implications for Cenozoic Eustatic and Climatic Change", "uid": "p0000643", "west": -179.9996}, {"awards": "0130525 Fraser, William", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0105", "datasets": [{"dataset_uid": "002605", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0105", "url": "https://www.rvdata.us/search/cruise/NBP0105"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The potential consequence of human impact on wildlife in Antarctica has been debated for many decades. Scientists, support staff and visitors in Antarctica may have an effect on the behavior and population dynamics of marine mammals and seabirds. Since the early 1970\u0027s, shipboard tourism has expanded to the point where it is timely to address the question, using a scientific research approach. The focus of this study is to examine the potential effect of tourist activities on the Adelie Penguins (Pygoscelis adeliae) in the Antarctic Peninsula. The topic has gathered the interest and opinions of those in private industry, the scientific community, government organizations and environmental groups. A key concern is that increases in these activities may eventually overcome the ability of research to address critical issues in a timely and biologically meaningful manner. The approach to understanding how tourism might affect Adelie Penguins must involve both a study of human activity and a study of natural variability in the physical environment. The ongoing Palmer Long Term Ecological Research program focuses on the ecosystem and its components and thus addresses the issues of natural variability. This project focuses on the human dimension and continues a tourist-monitoring program begun as a pilot project near Palmer Station. This site is in a geographic location that mirrors current patterns in tourism and tourist-wildlife interactions in the western Antarctic Peninsula. It also offers a setting that provides unique opportunities for human impacts research. This includes the presence of long-term databases that document environmental variability over multiple time and space scales in both marine and terrestrial habitats, and the ability to examine potential tourist impacts as part of controlled experiments. The results of the study will have important implications to understanding interactions between climate change and ecosystem response, and for detecting, mitigating and managing the consequences of human activities such as tourism.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Fraser, William; Smith, Raymond", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Monitoring the Human Impact and Environmental Variability on Adelie Penguins at Palmer Station, Antarctica", "uid": "p0000819", "west": null}, {"awards": "9731695 Klinkhammer, Gary", "bounds_geometry": "POLYGON((-179.9993 -43.56612,-143.99965 -43.56612,-108 -43.56612,-72.00035 -43.56612,-36.0007 -43.56612,-0.00105000000002 -43.56612,35.9986 -43.56612,71.99825 -43.56612,107.9979 -43.56612,143.99755 -43.56612,179.9972 -43.56612,179.9972 -45.894301,179.9972 -48.222482,179.9972 -50.550663,179.9972 -52.878844,179.9972 -55.207025,179.9972 -57.535206,179.9972 -59.863387,179.9972 -62.191568,179.9972 -64.519749,179.9972 -66.84793,143.99755 -66.84793,107.9979 -66.84793,71.99825 -66.84793,35.9986 -66.84793,-0.00104999999999 -66.84793,-36.0007 -66.84793,-72.00035 -66.84793,-108 -66.84793,-143.99965 -66.84793,-179.9993 -66.84793,-179.9993 -64.519749,-179.9993 -62.191568,-179.9993 -59.863387,-179.9993 -57.535206,-179.9993 -55.207025,-179.9993 -52.878844,-179.9993 -50.550663,-179.9993 -48.222482,-179.9993 -45.894301,-179.9993 -43.56612))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002227", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9507"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9731695 Klinkhammer This award supports participation of Oregon State University (OSU) researchers in an expedition of the German oceanographic research vessel POLARSTERN to the Antarctic Ocean (POLARSTERN cruise ANT-XV/2). Previous OSU researchers supported by the US Antarctic Program identified several areas of hydrothermal venting in the Bransfield Strait. This discovery has important implications to the biogeography of vent animals, the geological evolution of ore deposits, and the chemical and heat budgets of the Earth. The previous work sampled water and particles from above the vent sites at a reconnaissance level. Subsequent chemical analyses of these samples provided insight into the chemistry of fluids emanating from vents on the sea floor. The POLARSTERN cruise affords a unique opportunity to build on these discoveries in the Bransfield Strait, foster future international work in the Bransfield area, extend research on hydrothermal activity to other parts of the Antarctic Peninsula region, and develop a working relationship with a strong international group. In particular, the POLARSTERN expedition provides the opportunity for: 1) additional sampling of water and suspended particulate matter in the water column over the Bransfield hydrothermal sites this sampling would be aided by German photographic reconnaissance; 2) reconnaissance, to determine the broader geographical extent of hydrothermal activity, would be extended to the Scotia Arc and trench areas following the general theme of the German program which is fluid expulsion from the Scotia- Bransfield system; and 3) the use of unique tools available on the POLARSTERN such as a camera sled and grab bottom sampler. This work will make it possible to better define the location of hydrothermal vents and to begin to quantify the amount of water being expelled by this hydrothermal activity. If vents can be precisely located, the bottom photography holds the promise of revealing possible biologic al communities associated with these submarine hot springs.", "east": 179.9972, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56612, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Klinkhammer, Gary", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -66.84793, "title": "SGER Proposal: Rare Research Opportunity to Study Geotectonic Fluids in Bransfield Strait and Scotia Arc, Antarctica", "uid": "p0000640", "west": -179.9993}, {"awards": "0087401 Smith, Walker", "bounds_geometry": null, "dataset_titles": "Current Meter Data from the Ross Sea acquired with a Mooring deployed in December 2005 and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006); Expedition data of NBP0301B; Expedition data of NBP0305A; Expedition data of NBP0501; Expedition data of NBP0601A; Fluorometer Data acquired on Moorings deployed the Ross Sea and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006); Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601A", "datasets": [{"dataset_uid": "002627", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "601339", "doi": null, "keywords": "Antarctica; Current Meter; Mooring; NBP0601A; Oceans; Physical Oceanography; Ross Sea; Southern Ocean", "people": "Asper, Vernon; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Current Meter Data from the Ross Sea acquired with a Mooring deployed in December 2005 and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006)", "url": "https://www.usap-dc.org/view/dataset/601339"}, {"dataset_uid": "002623", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0601A", "url": "https://www.rvdata.us/search/cruise/NBP0601A"}, {"dataset_uid": "601333", "doi": null, "keywords": "Antarctica; Flourometer; Mooring; NBP0601A; Ross Sea; Southern Ocean", "people": "Asper, Vernon; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Fluorometer Data acquired on Moorings deployed the Ross Sea and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006)", "url": "https://www.usap-dc.org/view/dataset/601333"}, {"dataset_uid": "002622", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "002621", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0305A", "url": "https://www.rvdata.us/search/cruise/NBP0305A"}, {"dataset_uid": "002583", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0301B", "url": "https://www.rvdata.us/search/cruise/NBP0301B"}, {"dataset_uid": "601341", "doi": null, "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Fluid Chemistry Data; Mooring; NBP0601A; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Seawater Measurements; Southern Ocean", "people": "Smith, Walker; Asper, Vernon", "repository": "USAP-DC", "science_program": null, "title": "Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601A", "url": "https://www.usap-dc.org/view/dataset/601341"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "During the past few decades of oceanographic research, it has been recognized that significant variations in biogeochemical processes occur among years. Interannual variations in the Southern Ocean are known to occur in ice extent and concentration, in the composition of herbivore communities, and in bird and marine mammal distributions and reproductive success. However, little is known about the interannual variations in production of phytoplankton or the role that these variations play in the food web. This project will collect time series data on the seasonal production of phytoplankton in the southern Ross Sea, Antarctica. Furthermore, it will assess the interannual variations of the production of the two major functional groups of the system, diatoms and Phaeocystis Antarctica, a colonial haptophyte. The Ross Sea provides a unique setting for this type of investigation for a number of reasons. For example, a de facto time-series has already been initiated in the Ross Sea through the concentration of a number of programs in the past ten years. It also is well known that the species diversity is reduced relative to other systems and its seasonal production is as great as anywhere in the Antarctic. Most importantly, seasonal production of both the total phytoplankton community (as well as its two functional groups) can be estimated from late summer nutrient profiles. The project will involve short cruises on the US Coast Guard ice breakers in the southern Ross Sea that will allow the collection of water column nutrient and particulate after data at specific locations in the late summer of each of five years. Additionally, two moorings with in situ nitrate analyzers moored at fifteen will be deployed, thus collecting for the first time in the in the Antarctic a time-series of euphotic zone nutrient concentrations over the entire growing season. All nutrient data will be used to calculate seasonal production for each year in the southern Ross Sea and compared to previously collected information, thereby providing an assessment of interannual variations in net community production. Particulate matter data will allow us to estimate the amount of export from the surface layer by late summer, and therefore calculate the interannual variability of this ecosystem process. Interannual variations of seasonal production (and of the major taxa of producers) are a potentially significant feature in the growth and survival of higher trophic levels within the food web of the Ross Sea. They are also important in order to understand the natural variability in biogeochemical processes of the region. Because polar regions such as the Ross Sea are predicted to be impacted by future climate change, biological changes are also anticipated. Placing these changes in the context of natural variability is an essential element of understanding and predicting such alterations. This research thus seeks to quantify the natural variability of an Antarctic coastal system, and ultimately understand its causes and impacts on food webs and biogeochemical cycles of the Ross Sea.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "Ross Sea; AMD; USAP-DC; Amd/Us; USA/NSF; R/V NBP", "locations": "Ross Sea", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker; Gordon, Arnold", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Interannual Variability in the Antarctic-Ross Sea (IVARS): Nutrients and Seasonal Production", "uid": "p0000803", "west": null}, {"awards": "0338346 Cande, Steven; 0338317 Stock, Joann", "bounds_geometry": "POLYGON((-179.9987 71.33822,-143.998893 71.33822,-107.999086 71.33822,-71.999279 71.33822,-35.999472 71.33822,0.000334999999978 71.33822,36.000142 71.33822,71.999949 71.33822,107.999756 71.33822,143.999563 71.33822,179.99937 71.33822,179.99937 59.8431,179.99937 48.34798,179.99937 36.85286,179.99937 25.35774,179.99937 13.86262,179.99937 2.3675,179.99937 -9.12762,179.99937 -20.62274,179.99937 -32.11786,179.99937 -43.61298,143.999563 -43.61298,107.999756 -43.61298,71.999949 -43.61298,36.000142 -43.61298,0.000335000000007 -43.61298,-35.999472 -43.61298,-71.999279 -43.61298,-107.999086 -43.61298,-143.998893 -43.61298,-179.9987 -43.61298,-179.9987 -32.11786,-179.9987 -20.62274,-179.9987 -9.12762,-179.9987 2.3675,-179.9987 13.86262,-179.9987 25.35774,-179.9987 36.85286,-179.9987 48.34798,-179.9987 59.8431,-179.9987 71.33822))", "dataset_titles": "Expedition Data; Expedition data of NBP0501", "datasets": [{"dataset_uid": "001652", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0406"}, {"dataset_uid": "001690", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304B"}, {"dataset_uid": "001587", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0507"}, {"dataset_uid": "001561", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0607A"}, {"dataset_uid": "001691", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304C"}, {"dataset_uid": "001512", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0804"}, {"dataset_uid": "001609", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0501B"}, {"dataset_uid": "002627", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "001692", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304D"}, {"dataset_uid": "001557", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0607C"}, {"dataset_uid": "001577", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0602"}, {"dataset_uid": "001660", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0403"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project will utilize the R/VIB Nathaniel B. Palmer\u0027s transit cruises to collect marine geophysical data on targets-of-opportunity in the southern oceans. Because the Palmer generally traverses regions only sparsely surveyed with geophysical instruments, this project represents a cost-effective way to collect important new data. The work\u0027s focus is expanding our knowledge of plate motion histories for the Antarctic and surrounding plates. The ultimate goals are improving global plate reconstructions and gaining new insight into general plate kinematics and dynamics and lithospheric rheology. Only slight deviations from the straight routes are required, and we expect to operate on one cruise per year over the three years of the project. The first cruise from New Zealand to Chile will survey a flow line of Pacific-Antarctic plate motion along the Menard fracture zone, which crosses the East Pacific Rise at ~50 S latitude. Swath bathymetry, gravity, magnetics, and a small amount of seismic reflection profiling will be collected to determine the exact trace of the fracture zone and its relationship to the associated gravity anomaly seen in shipboard and satellite radar altimetry data. These observations are critical for precise plate reconstructions, and will provide GPS-navigated locations of a major fracture zone near the northern end of the Pacific-Antarctic boundary. These data will be used in combination with similar data from the Pitman fracture zone at the southwestern end of the plate boundary and magnetic anomalies from previous cruises near the Menard fracture zone to improve high-precision plate reconstructions and evaluate the limits of internal deformation of the Pacific and Antarctic plates. The science plan for cruises in following years will be designed once transit schedules are set. In terms of broader impacts, we plan to teach an on-board marine geophysics class to graduate and undergraduate students on two cruises. The class consists of daily classroom lectures about the instruments and data; several hours per day of watch standing and data processing; and work by each student on an independent research project. We expect to accommodate 15 students per class, including participants from primarily undergraduate institutions with high minority enrollments.", "east": 179.99937, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": 71.33822, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Croon, Marcel; Stock, Joann; Miller, Alisa; Cande, Steven; Gordon, Arnold", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -43.61298, "title": "Collaborative Research: Collection of Marine Geophysical Data on Transits of the Nathaniel B. Palmer", "uid": "p0000121", "west": -179.9987}, {"awards": "0230069 Naveen, Ron", "bounds_geometry": "POLYGON((-68.0489 -52.7302,-66.96539 -52.7302,-65.88188 -52.7302,-64.79837 -52.7302,-63.71486 -52.7302,-62.63135 -52.7302,-61.54784 -52.7302,-60.46433 -52.7302,-59.38082 -52.7302,-58.29731 -52.7302,-57.2138 -52.7302,-57.2138 -53.97453,-57.2138 -55.21886,-57.2138 -56.46319,-57.2138 -57.70752,-57.2138 -58.95185,-57.2138 -60.19618,-57.2138 -61.44051,-57.2138 -62.68484,-57.2138 -63.92917,-57.2138 -65.1735,-58.29731 -65.1735,-59.38082 -65.1735,-60.46433 -65.1735,-61.54784 -65.1735,-62.63135 -65.1735,-63.71486 -65.1735,-64.79837 -65.1735,-65.88188 -65.1735,-66.96539 -65.1735,-68.0489 -65.1735,-68.0489 -63.92917,-68.0489 -62.68484,-68.0489 -61.44051,-68.0489 -60.19618,-68.0489 -58.95185,-68.0489 -57.70752,-68.0489 -56.46319,-68.0489 -55.21886,-68.0489 -53.97453,-68.0489 -52.7302))", "dataset_titles": "Expedition Data; Expedition data of LMG0413A; Expedition data of LMG0514; Expedition data of LMG0611; Long-term Data Collection at Select Antarctic Peninsula Visitor Sites", "datasets": [{"dataset_uid": "001686", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0308"}, {"dataset_uid": "001626", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0413A"}, {"dataset_uid": "002679", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0413A", "url": "https://www.rvdata.us/search/cruise/LMG0413A"}, {"dataset_uid": "002681", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0611", "url": "https://www.rvdata.us/search/cruise/LMG0611"}, {"dataset_uid": "002680", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0514", "url": "https://www.rvdata.us/search/cruise/LMG0514"}, {"dataset_uid": "001547", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0611B"}, {"dataset_uid": "600032", "doi": "10.15784/600032", "keywords": "Antarctica; Biota; Penguin; Petermann Island", "people": "Naveen, Ronald", "repository": "USAP-DC", "science_program": null, "title": "Long-term Data Collection at Select Antarctic Peninsula Visitor Sites", "url": "https://www.usap-dc.org/view/dataset/600032"}, {"dataset_uid": "001585", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0514"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The Antarctic Site Inventory Project has collected biological data and site-descriptive information in the Antarctic Peninsula region since 1994. This research effort has provided data on those sites which are visited by tourists on shipboard expeditions in the region. The aim is to obtain data on the population status of several key species of Antarctic seabirds, which might be affected by the cumulative impact resulting from visits to the sites. This project will continue the effort by focusing on two heavily-visited Antarctic Peninsula sites: Paulet Island, in the northwestern Weddell Sea and Petermann Island, in the Lemaire Channel near Anvers Island. These sites were selected because both rank among the ten most visited sites in Antarctica each year in terms of numbers of visitors and zodiac landings; both are diverse in species composition, and both are sensitive to potential environmental disruptions from visitors. These data collected focus on two important biological parameters for penguins and blue-eyed shags: (1) breeding population size (number of occupied nests) and (2) breeding success (number of chicks per occupied nests). A long-term data program will be supported, with studies at the two sites over a five-year period. The main focus will be at Petermann Island, selected for intensive study due to its visitor status and location in the region near Palmer Station. This will allow for comparative data with the Palmer Long Term Ecological Research program. Demographic data will be collected in accordance with Standard Methods established by the Convention for the Conservation of Antarctic Marine Living Resources Ecosystem Monitoring Program and thus will be comparable with similar data sets being collected by other international Antarctic Treaty nation research programs. While separating human-induced change from change resulting from a combination of environmental factors will be difficult, this work will provide a first step to identify potential impacts. These long-term data sets will contribute to a better understanding of biological processes in the entire region and will contribute valuable information to be used by the Antarctic Treaty Parties as they address issues in environmental stewardship in Antarctica.", "east": -57.2138, "geometry": "POINT(-62.63135 -58.95185)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": true, "keywords": "R/V LMG; FIELD SURVEYS", "locations": null, "north": -52.7302, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Yen, Jeannette; Naveen, Ronald; Leger, Dave", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -65.1735, "title": "Long-term Data Collection at Select Antarctic Peninsula Visitor Sites", "uid": "p0000122", "west": -68.0489}, {"awards": "9726180 Dorman, LeRoy", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP9905", "datasets": [{"dataset_uid": "002581", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP9905", "url": "https://www.rvdata.us/search/cruise/NBP9905"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Office of Polar Programs of the National Science Foundation, supports research to investigate the seismicity and tectonics of the South Shetland Arc and the Bransfield Strait. This region presents an intriguing and unique tectonic setting, with slowing of subduction, cessation of island arc volcanism, as well as the apparent onset of backarc rifting occurring within the last four million years. This project will carry out a 5-month deployment of 14 ocean bottom seismographs (OBSs) to complement and extend a deployment of 6 broadband land seismic stations that were successfully installed during early 1997. The OBSs include 2 instruments with broadband sensors, and all have flowmeters for measuring and sampling hydrothermal fluids. The OBSs will be used to examine many of the characteristics of the Shetland- Bransfield tectonic system, including: --- The existence and depth of penetration of a Shetland Slab: The existence of a downgoing Shetland slab will be determined from earthquake locations and from seismic tomography. The maximum depth of earthquake activity and the depth of the slab velocity anomaly will constrain the current configuration of the slab, and may help clarify the relationship between the subducting slab and the cessation of arc volcanism. -- Shallow Shetland trench seismicity?: No teleseismic shallow thrust faulting seismicity has been observed along the South Shetland Trench from available seismic information. Using the OBS data, the level of small earthquake activity along the shallow thrust zone will be determined and compared to other regions undergoing slow subduction of young oceanic lithosphere, such as Cascadia, which also generally shows very low levels of thrust zone seismicity. -- Mode of deformation along the Bransfield Rift: The Bransfield backarc has an active rift in the center, but there is considerable evidence for off-rift faulting. There is a long-standing controversy about whet her back-arc extension occurs along discrete rift zones, or is more diffuse geographically. This project will accurately locate small earthquakes to better determine whether Bransfield extension is discrete or diffuse. -- Identification of volcanism and hydrothermal activity: Seismic records will be used to identify the locations of active seafloor volcanism along the Bransfield rift. Flowmeters attached to the OBSs will record and sample the fluid flux out of the sediments. -- Upper mantle structure of the Bransfield - evidence for partial melting?: Other backarc basins show very slow upper mantle seismic velocities and high seismic attenuation, characteristics due to the presence of partially molten material. This project will use seismic tomography to resolve the upper mantle structure of the Bransfield backarc, allowing comparison with other backarc regions and placing constraints on the existence of partially molten material and the importance of partial melting as a mantle process in this region. Collaborative awards: OPP 9725679 and OPP 9726180", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Wiens, Douglas", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Study of the Structure and Tectonics of the South Shetland Trench and Bransfield Backarc Using Ocean Bottom Seismographs", "uid": "p0000801", "west": null}, {"awards": "9615053 Domack, Eugene", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG9802", "datasets": [{"dataset_uid": "002718", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG9802", "url": "https://www.rvdata.us/search/cruise/LMG9802"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Domack: OPP 9615053 Manley: OPP 9615670 Banerjee: OPP 9615695 Dunbar: OPP 9615668 Ishman: OPP 9615669 Leventer: OPP 9714371 Abstract This award supports a multi-disciplinary, multi-institutional effort to elucidate the detailed climate history of the Antarctic Peninsula during the Holocene epoch (the last 10,000 years). The Holocene is an important, but often overlooked, portion of the Antarctic paleoclimatic record because natural variability in Holocene climate on time scales of decades to millennia can be evaluated as a model for our present \"interglacial\" world. This project builds on over ten years of prior investigation into the depositional processes, productivity patterns and climate regime of the Antarctic Peninsula. This previous work identified key locations that contain ultra-high resolution records of past climatic variation. These data indicate that solar cycles operating on multi-century and millennial time scales are important regulators of meltwater production and paleoproductivity. These marine records can be correlated with ice core records in Greenland and Antarctica. This project will focus on sediment dispersal patterns across the Palmer Deep region. The objective is to understand the present links between the modern climatic and oceanographic systems and sediment distribution. In particular, additional information is needed regarding the influence of sea ice on the distribution of both biogenic and terrigenous sediment distribution. Sediment samples will be collected with a variety of grab sampling and coring devices. Analytical work will include carbon-14 dating of surface sediments using accellerator mass spectrometry and standard sedimentologic, micropaleontologic and magnetic granulometric analyses. This multiparameter approach is the most effective way to extract the paleoclimatic signals contained in the marine sediment cores. Two additional objectives are the deployment of sediment traps in front of the Muller Ice Shelf in Lallemand Fjord and seismic reflection work in conjunction with site augmentation funded through the Joint Oceanographic Institute. The goal of sediment trap work is to address whether sand transport and deposition adjacent to the ice shelf calving line results from meltwater or aeolian processes. In addition, the relationship between sea ice conditions and primary productivity will be investigated. The collection of a short series of seismic lines across the Palmer Deep basins will fully resolve the question of depth to acoustic basement. The combination of investigators on this project, all with many years of experience working in high latitude settings, provides an effective team to complete the project in a timely fashion. A combination of undergraduate, graduate and post-graduate students will be involved in all stages of the project so that educational objectives will be met in-tandem with research goals of the project.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Domack, Eugene Walter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Holocene Paleoenvironmental Change Along the Antarctic Peninsula: A Test of the Solar/Bi-Polar Signal", "uid": "p0000869", "west": null}, {"awards": "0538148 Huber, Bruce", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0801; Processed CurrentMeter Data from the Adare Basin near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1101 ; Processed CurrentMeter Data from the Ross Sea near Antarctica acquired during the Nathaniel B. Palmer expedition NBP0801", "datasets": [{"dataset_uid": "601344", "doi": null, "keywords": "Antarctica; Cape Adare; Mooring; NBP0801; Physical Oceanography; Ross Sea; R/v Nathaniel B. Palmer; Salinity; Southern Ocean; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed CurrentMeter Data from the Ross Sea near Antarctica acquired during the Nathaniel B. Palmer expedition NBP0801", "url": "https://www.usap-dc.org/view/dataset/601344"}, {"dataset_uid": "601343", "doi": null, "keywords": "Antarctica; Mooring; NBP1101; Ross Sea; Salinity; Southern Ocean; Temperature", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": null, "title": "Processed CurrentMeter Data from the Adare Basin near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1101 ", "url": "https://www.usap-dc.org/view/dataset/601343"}, {"dataset_uid": "002647", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0801", "url": "https://www.rvdata.us/search/cruise/NBP0801"}, {"dataset_uid": "001517", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0801"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "An array of moorings will be deployed and maintained east of Cape Adare, Antarctica, at the northwestern corner of the Ross Sea to observe the properties of Antarctic Bottom Water (AABW) exiting the Ross Sea. This location has been identified from recent studies as an ideal place to make such measurements. Antarctic Bottom Water has the highest density of the major global water masses, and fills the deepest parts of the world\u0027s oceans. Because it obtains many of its characteristics during its contact with the atmosphere and with glacial ice along the continental margins of Antarctica, it is expected that changes in newly-formed AABW may represent an effective indicator for abrupt climate change. The heterogeneous nature of the source regions around Antarctica complicates the observation of newly-formed AABW properties. The two most important source regions for AABW are within the Weddell and the Ross Seas, with additional sources drawn from the east Antarctic margins. In the northwestern Weddell Sea, several programs have been undertaken in the last decade to monitor the long term variability of Weddell Sea Deep and Bottom Water, precursors of AABW originating from the Weddell Sea, however no such systematic efforts have yet been undertaken to make longterm measurements of outflow from the Ross Sea. The proposed study will significantly improve our knowledge of the long term variability in the outflow of deep and bottom water from the Ross Sea, and will provide the beginnings of a long-term monitoring effort which ultimately will allow detection of changes in the ocean in the context of global climate change. When joined with similar efforts ongoing in the Weddell Sea, long-term behavior and possible coupling of these two important sources of the ocean\u0027s deepest water mass can be examined in detail.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Caron, Bruce", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Cape Adare Long-term Mooring (CALM)", "uid": "p0000838", "west": null}, {"awards": "0094078 Bart, Philip", "bounds_geometry": "POLYGON((-179.99992 -72.00044,-143.999984 -72.00044,-108.000048 -72.00044,-72.000112 -72.00044,-36.000176 -72.00044,-0.000239999999991 -72.00044,35.999696 -72.00044,71.999632 -72.00044,107.999568 -72.00044,143.999504 -72.00044,179.99944 -72.00044,179.99944 -72.574101,179.99944 -73.147762,179.99944 -73.721423,179.99944 -74.295084,179.99944 -74.868745,179.99944 -75.442406,179.99944 -76.016067,179.99944 -76.589728,179.99944 -77.163389,179.99944 -77.73705,143.999504 -77.73705,107.999568 -77.73705,71.999632 -77.73705,35.999696 -77.73705,-0.000240000000019 -77.73705,-36.000176 -77.73705,-72.000112 -77.73705,-108.000048 -77.73705,-143.999984 -77.73705,-179.99992 -77.73705,-179.99992 -77.163389,-179.99992 -76.589728,-179.99992 -76.016067,-179.99992 -75.442406,-179.99992 -74.868745,-179.99992 -74.295084,-179.99992 -73.721423,-179.99992 -73.147762,-179.99992 -72.574101,-179.99992 -72.00044))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001648", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0301A"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "PROPOSAL NO.: 0094078\u003cbr/\u003ePRINCIPAL INVESTIGATOR: Bart, Philip\u003cbr/\u003eINSTITUTION NAME: Louisiana State University \u0026 Agricultural and Mechanical College\u003cbr/\u003eTITLE: CAREER: Relative frequency and phase of extreme expansions of the Antarctic Ice Sheets during the late Neogene\u003cbr/\u003eNSF RECEIVED DATE: 07/27/2000\u003cbr/\u003e\u003cbr/\u003ePROJECT SUMMARY\u003cbr/\u003e\u003cbr/\u003eExpansions and contractions of the Antarctic Ice Sheets (AISs) have undoubtedly had a profound influence on Earth\u0027s climate and global sea-level. However, rather than being a single entity, the Antarctic cryosphere consists of three primary elements: 1) the East Antarctic Ice Sheet (EAIS); 2) the West Antarctic Ice Sheet (WAIS); and 3) the Antarctic Peninsula Ice Cap (APIC). The distinguishing characteristics include significant differences in: 1) ice volume; 2) substratum elevation; 3) ice-surface elevation; and 4) location with respect to latitude. Various lines of evidence indicate that the AISs have undergone significant fluctuations in the past and that fluctuations will continue to occur in the future. The exact nature of the fluctuations has been the subject of many lively debates. According to one line of reasoning, the land-based EAIS has been relatively stable, experiencing only minor fluctuations since forming in the middle Miocene, whereas the marine-based WAIS has been dynamic, waxing and waning frequently since the late Miocene. According to an alternate hypothesis, the ice sheets advanced and retreated synchronously. These two views are incompatible. \u003cbr/\u003e\u003cbr/\u003eThe first objective of this proposal is to compare the long-term past behavior of the WAIS to that of the EAIS and APIC. The fluctuations of the AISs involve many aspects (the frequency of changes, the overall magnitude of ice-volume change, etc.), and the activities proposed here specifically concern the frequency and phase of extreme advances of the ice sheet to the continental shelf. The project will build upon previous seismic-stratigraphic investigations of the continental shelves. These studies have clarified many issues concerning the minimum frequency of extreme expansions for the individual ice sheets, but some important questions remain. During the course of the project, the following questions will be evaluated.\u003cbr/\u003e\u003cbr/\u003eQuestion 1) Were extreme advances of the EAIS and WAIS across the shelf of a similar frequency and coeval? This evaluation is possible because the western Ross Sea continental shelf (Northern Basin) receives drainage from the EAIS, and the eastern Ross Sea (Eastern Basin) receives drainage from the WAIS. Quantitative analyses of the extreme advances from these two areas have been conducted by Alonso et al. (1992) and Bart et al. (2000), respectively. However, the existing single-channel seismic grids are incomplete and can not be used to determine the stratigraphic correlations from Northern Basin to Eastern Basin. It is proposed that high-resolution seismic data (~2000 kms) be acquired to address this issue.\u003cbr/\u003e\u003cbr/\u003eQuestion 2) Were extreme advances of the APIC across the shelf as frequent as inferred by Bart and Anderson (1995)? Bart and Anderson (1995) inferred that the APIC advanced across the continental shelf at least 30 times since the middle Miocene. This is significant because it suggests that the advances of the small APIC were an order of magnitude more frequent than the advances of the EAIS and WAIS. Others contest the Bart and Anderson (1995) glacial-unconformity interpretation of seismic reflections, and argue that the advances of the APIC were far fewer (i.e., Larter et al., 1997). The recent drilling on the Antarctic Peninsula outer continental shelf has sampled some but not all of the glacial units, but the sediment recovery was poor, and thus, the glacial history interpretation is still ambiguous. The existing high-resolution seismic grids from the Antarctic Peninsula contain only one regional strike line on the outer continental shelf. This is inadequate to address the controversy of the glacial-unconformity interpretation and the regional correlation of the recent ODP results. It is proposed that high-resolution seismic data (~1000 kms) be acquired in a forthcoming (January 2002) cruise to the Antarctic Peninsula to address these issues.\u003cbr/\u003e\u003cbr/\u003eThe second objective of this project is 1) to expand the PI\u0027s effort to integrate his ongoing and the proposed experiments into a graduate-level course at LSU, and 2) to develop a pilot outreach program with a Baton Rouge public high school. The Louisiana Department of Education has adopted scientific standards that apply to all sciences. These standards reflect what 9th through 12th grade-level students should be able to do and know. The PI will target one of these standards, the Science As Inquiry Standard 1 Benchmark. The PI will endeavor to share with the students the excitement of conducting scientific research as a way to encourage the students to pursue earth science as a field of study at the university level.", "east": 179.99944, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -72.00044, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Bart, Philip", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.73705, "title": "PECASE: Relative frequency and phase of extreme expansions of the Antarctic Ice Sheets during the late Neogene", "uid": "p0000593", "west": -179.99992}, {"awards": "0088143 Luyendyk, Bruce; 0087392 Bartek, Louis", "bounds_geometry": "POLYGON((-179.99786 -75.91667,-143.99852 -75.91667,-107.99918 -75.91667,-71.99984 -75.91667,-36.0005 -75.91667,-0.00115999999997 -75.91667,35.99818 -75.91667,71.99752 -75.91667,107.99686 -75.91667,143.9962 -75.91667,179.99554 -75.91667,179.99554 -76.183531,179.99554 -76.450392,179.99554 -76.717253,179.99554 -76.984114,179.99554 -77.250975,179.99554 -77.517836,179.99554 -77.784697,179.99554 -78.051558,179.99554 -78.318419,179.99554 -78.58528,143.9962 -78.58528,107.99686 -78.58528,71.99752 -78.58528,35.99818 -78.58528,-0.00116000000003 -78.58528,-36.0005 -78.58528,-71.99984 -78.58528,-107.99918 -78.58528,-143.99852 -78.58528,-179.99786 -78.58528,-179.99786 -78.318419,-179.99786 -78.051558,-179.99786 -77.784697,-179.99786 -77.517836,-179.99786 -77.250975,-179.99786 -76.984114,-179.99786 -76.717253,-179.99786 -76.450392,-179.99786 -76.183531,-179.99786 -75.91667))", "dataset_titles": "Expedition Data; NBP0301 data; NBP0306 data", "datasets": [{"dataset_uid": "000105", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0306 data", "url": "https://www.rvdata.us/search/cruise/NBP0306"}, {"dataset_uid": "001724", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0301"}, {"dataset_uid": "001668", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0306"}, {"dataset_uid": "000104", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0301 data", "url": "https://www.rvdata.us/search/cruise/NBP0301"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Luyendyk et.al.: OPP 0088143\u003cbr/\u003eBartek: OPP 0087392\u003cbr/\u003eDiebold: OPP 0087983\u003cbr/\u003e\u003cbr/\u003eThis award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a collaborative research program in marine geology and geophysics in the southern central and eastern Ross Sea. The project will conduct sites surveys for drilling from the Ross Ice Shelf into the seafloor beneath it. Many of the outstanding problems concerning the evolution of the East and West Antarctic Ice Sheets, Antarctic climate, global sea level, and the tectonic history of the West Antarctic Rift System can be addressed by drilling into the seafloor of the Ross Sea. Climate data for Cretaceous and Early Cenozoic time are lacking for this sector of Antarctica. Climate questions include: Was there any ice in Late Cretaceous time? What was the Antarctic climate during the Paleocene-Eocene global warming? When was the Cenozoic onset of Antarctic glaciation, when did glaciers reach the coast and when did they advance out onto the margin? Was the Ross Sea shelf non-marine in Late Cretaceous time; when did it become marine? Tectonic questions include: What was the timing of the Cretaceous extension in the Ross Sea rift; where was it located? What is the basement composition and structure? Where are the time and space limits of the effects of Adare Trough spreading? Another drilling objective is to sample and date the sedimentary section bounding the mapped RSU6 unconformity in the Eastern Basin and Central Trough to resolve questions about its age and regional extent. Deep Sea Drilling Project (DSDP) Leg 28 completed sampling at four drill sites in the early 1970\u0027s but had low recovery and did not sample the Early Cenozoic. Other drilling has been restricted to the McMurdo Sound area of the western Ross Sea and results can be correlated into the Victoria Land Basin but not eastward across basement highs. Further, Early Cenozoic and Cretaceous rocks have not been sampled. A new opportunity is developing to drill from the Ross Ice Shelf. This is a successor program to the Cape Roberts Drilling Project. One overriding difficulty is the need for site surveys at drilling locations under the ice shelf. This project will overcome this impediment by conducting marine geophysical drill site surveys at the front of the Ross Ice Shelf in the Central Trough and Eastern Basin. The surveys will be conducted a kilometer or two north of the ice shelf front where recent calving events have resulted in a southerly position of the ice shelf edge. In several years the northward advance of the ice shelf will override the surveyed locations and drilling could be accomplished. Systems to be used include swath bathymetry, gravity, magnetics, chirp sonar, high resolution seismic profiling, and 48 fold seismics. Cores will be collected to obtain samples for geotechnical properties, to study sub-ice shelf modern sedimentary processes, and at locations where deeper section is exposed.\u003cbr/\u003e\u003cbr/\u003eThis survey will include long profiles and detailed grids over potential drill sites. Survey lines will be tied to existing geophysical profiles and DSDP 270. A recent event that makes this plan timely is the calving of giant iceberg B-15 (in March, 2000) and others from the ice front in the eastern Ross Sea. This new calving event and one in 1987 have exposed 16,000 square kilometers of seafloor that had been covered by ice shelf for decades and is not explored. Newly exposed territory can now be mapped by modern geophysical methods. This project will map geological structure and stratigraphy below unconformity RSU6 farther south and east, study the place of Roosevelt Island in the Ross Sea rifting history, and determine subsidence history during Late Cenozoic time (post RSU6) in the far south and east. Finally the project will observe present day sedimentary processes beneath the ice shelf in the newly exposed areas.", "east": 179.99554, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": true, "keywords": "R/V NBP", "locations": null, "north": -75.91667, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Bartek, Louis; Luyendyk, Bruce P.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.58528, "title": "Collaborative Research: Antarctic Cretaceous-Cenozoic Climate, Glaciation, and Tectonics: Site surveys for drilling from the edge of the Ross Ice Shelf", "uid": "p0000425", "west": -179.99786}, {"awards": "9814622 Wiens, Douglas", "bounds_geometry": "POLYGON((-70.90604 -52.35474,-69.307306 -52.35474,-67.708572 -52.35474,-66.109838 -52.35474,-64.511104 -52.35474,-62.91237 -52.35474,-61.313636 -52.35474,-59.714902 -52.35474,-58.116168 -52.35474,-56.517434 -52.35474,-54.9187 -52.35474,-54.9187 -53.658393,-54.9187 -54.962046,-54.9187 -56.265699,-54.9187 -57.569352,-54.9187 -58.873005,-54.9187 -60.176658,-54.9187 -61.480311,-54.9187 -62.783964,-54.9187 -64.087617,-54.9187 -65.39127,-56.517434 -65.39127,-58.116168 -65.39127,-59.714902 -65.39127,-61.313636 -65.39127,-62.91237 -65.39127,-64.511104 -65.39127,-66.109838 -65.39127,-67.708572 -65.39127,-69.307306 -65.39127,-70.90604 -65.39127,-70.90604 -64.087617,-70.90604 -62.783964,-70.90604 -61.480311,-70.90604 -60.176658,-70.90604 -58.873005,-70.90604 -57.569352,-70.90604 -56.265699,-70.90604 -54.962046,-70.90604 -53.658393,-70.90604 -52.35474))", "dataset_titles": "Expedition Data; Expedition data of LMG0003A", "datasets": [{"dataset_uid": "002059", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9905"}, {"dataset_uid": "002688", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0003A", "url": "https://www.rvdata.us/search/cruise/LMG0003A"}, {"dataset_uid": "001854", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0106"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided jointly by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to transform three temporary seismometers in the Antarctic Peninsula into semi-permanent stations and to continue basic research using these data. During 1997 and 1998, a network of 11 broadband seismographs in the Antarctic Peninsula region and southernmost Chilean Patagonia were installed and maintained. Data return from this project has been excellent and interesting initial results have been produced. The continued operation of these instruments over a longer time period would be highly beneficial because the number of larger magnitude regional earthquakes is small and so a longer time is needed to acquire data. However, instruments from this project are borrowed from the IRIS-PASSCAL instrument pool and must be returned to PASSCAL in April, 1999. This award provides funds to convert three stations at permanent Chilean bases in the Antarctic to permanent stations, and to continue the seismological investigation of the region for a period of four years. As part of this project, a fourth station, in Chilean Patagonia, will continue to be operated using Washington University equipment. The funding of this project will enable continued collaboration between Washington University and the Universidad de Chile in the operation of these stations, and the data will be forwarded to the IRIS data center as well as to other international seismological collaborators. Mutual data exchanges with other national groups with Antarctic seismology research programs will provide access to broadband data from a variety of other proprietary broadband stations in the region. The data will be used to study the seismicity and upper mantle velocity structure of several complicated tectonic regions in the area, including the South Shetland subduction zone, the Bransfield backarc rift, and diffuse plate boundaries in Patagonia, Drake Passage, and along the South Scotia Ridge. In particular, the operation of these stations over a longer time period will allow a better understanding of the seismicity of the South Shetland Trench, an unusual subduction zone showing very slow subduction of young lithosphere. These seismometers will also be used to record airgun shots during a geophysical cruise in the Bransfield Strait that is being planned by the University of Texas for April, 2000. These data will provide important constraints on the crustal structure beneath the stations, and the improved structural models will enable implementation of more precise earthquake location procedures in support of a seismological understanding of the region.", "east": -54.9187, "geometry": "POINT(-62.91237 -58.873005)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V LMG; R/V NBP", "locations": null, "north": -52.35474, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Wiens, Douglas; Visbeck, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -65.39127, "title": "Acquisition and Operation of Broadband Seismograph Equipment at Chilean Bases in the Antarctic Peninsula Region", "uid": "p0000604", "west": -70.90604}, {"awards": "0125818 Gargett, Ann", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0508", "datasets": [{"dataset_uid": "001584", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0508"}, {"dataset_uid": "002610", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0508", "url": "https://www.rvdata.us/search/cruise/NBP0508"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V NBP; B-15J", "locations": "B-15J", "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Neale, Patrick", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Interactive effects of UV and vertical mixing on phytoplankton and bacterioplankton in the Ross Sea", "uid": "p0000822", "west": null}, {"awards": "0338371 Hallet, Bernard; 0338137 Anderson, John", "bounds_geometry": "POLYGON((-74.59492 -45.98986,-74.072309 -45.98986,-73.549698 -45.98986,-73.027087 -45.98986,-72.504476 -45.98986,-71.981865 -45.98986,-71.459254 -45.98986,-70.936643 -45.98986,-70.414032 -45.98986,-69.891421 -45.98986,-69.36881 -45.98986,-69.36881 -46.835236,-69.36881 -47.680612,-69.36881 -48.525988,-69.36881 -49.371364,-69.36881 -50.21674,-69.36881 -51.062116,-69.36881 -51.907492,-69.36881 -52.752868,-69.36881 -53.598244,-69.36881 -54.44362,-69.891421 -54.44362,-70.414032 -54.44362,-70.936643 -54.44362,-71.459254 -54.44362,-71.981865 -54.44362,-72.504476 -54.44362,-73.027087 -54.44362,-73.549698 -54.44362,-74.072309 -54.44362,-74.59492 -54.44362,-74.59492 -53.598244,-74.59492 -52.752868,-74.59492 -51.907492,-74.59492 -51.062116,-74.59492 -50.21674,-74.59492 -49.371364,-74.59492 -48.525988,-74.59492 -47.680612,-74.59492 -46.835236,-74.59492 -45.98986))", "dataset_titles": "Expedition data of NBP0505; Expedition data of NBP0703; NBP0505 CTD data; NBP0505 sediment core locations", "datasets": [{"dataset_uid": "601362", "doi": "10.15784/601362", "keywords": "Chile; Fjord; Marine Geoscience; NBP0505; R/v Nathaniel B. Palmer; Sample/collection Description; Sample/Collection Description; Sediment Core; Sediment Corer; Station List", "people": "Anderson, John; Wellner, Julia", "repository": "USAP-DC", "science_program": null, "title": "NBP0505 sediment core locations", "url": "https://www.usap-dc.org/view/dataset/601362"}, {"dataset_uid": "601363", "doi": "10.15784/601363", "keywords": "Chile; CTD; CTD Data; Depth; Fjord; NBP0505; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Wellner, Julia; Anderson, John", "repository": "USAP-DC", "science_program": null, "title": "NBP0505 CTD data", "url": "https://www.usap-dc.org/view/dataset/601363"}, {"dataset_uid": "002609", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0505", "url": "https://www.rvdata.us/search/cruise/NBP0505"}, {"dataset_uid": "002642", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0703", "url": "https://www.rvdata.us/search/cruise/NBP0703"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project examines the role of glacier dynamics in glacial sediment yields. The results will shed light on how glacial erosion influences both orogenic processes and produces sediments that accumulate in basins, rich archives of climate variability. Our hypothesis is that erosion rates are a function of sliding speed, and should diminish sharply as the glacier\u0027s basal temperatures drop below the melting point. To test this hypothesis, we will determine sediment accumulation rates from seismic studies of fjord sediments for six tidewater glaciers that range from fast-moving temperate glaciers in Patagonia to slow-moving polar glaciers on the Antarctic Peninsula. Two key themes are addressed for each glacier system: 1) sediment yields and erosion rates by determining accumulation rates within the fjords using seismic profiles and core data, and 2) dynamic properties and basin characteristics of each glacier in order to seek an empirical relationship between glacial erosion rates and ice dynamics. The work is based in Patagonia and the Antarctic Peninsula, ideal natural laboratories for these purposes because the large latitudinal range provides a large range of precipitation and thermal regimes over relatively homogeneous lithologies and tectonic settings. Prior studies of these regions noted significant decreases in glaciomarine sediment accumulations in the fjords to the south. As well, the fjords constitute accessible and nearly perfect natural sediment traps.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this study include inter-disciplinary collaboration with Chilean glaciologists and marine geologists, support for one postdoctoral and three doctoral students, inclusion of undergraduates in research, and outreach to under-represented groups in Earth sciences and K-12 educators. The results of the project will also contribute to a better understanding of the linkages between climate and evolution of all high mountain ranges.", "east": -69.36881, "geometry": "POINT(-71.981865 -50.21674)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP; Penguin Glacier", "locations": null, "north": -45.98986, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, John; Hallet, Bernard; Wellner, Julia", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -54.44362, "title": "Collaborative Research: Controls on Sediment Yields from Tidewater Glaciers from Patagonia to Antarctica", "uid": "p0000821", "west": -74.59492}, {"awards": "0338248 Takahashi, Taro", "bounds_geometry": "POLYGON((-68.0051 -52.7573,-67.35191 -52.7573,-66.69872 -52.7573,-66.04553 -52.7573,-65.39234 -52.7573,-64.73915 -52.7573,-64.08596 -52.7573,-63.43277 -52.7573,-62.77958 -52.7573,-62.12639 -52.7573,-61.4732 -52.7573,-61.4732 -53.96927,-61.4732 -55.18124,-61.4732 -56.39321,-61.4732 -57.60518,-61.4732 -58.81715,-61.4732 -60.02912,-61.4732 -61.24109,-61.4732 -62.45306,-61.4732 -63.66503,-61.4732 -64.877,-62.12639 -64.877,-62.77958 -64.877,-63.43277 -64.877,-64.08596 -64.877,-64.73915 -64.877,-65.39234 -64.877,-66.04553 -64.877,-66.69872 -64.877,-67.35191 -64.877,-68.0051 -64.877,-68.0051 -63.66503,-68.0051 -62.45306,-68.0051 -61.24109,-68.0051 -60.02912,-68.0051 -58.81715,-68.0051 -57.60518,-68.0051 -56.39321,-68.0051 -55.18124,-68.0051 -53.96927,-68.0051 -52.7573))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001572", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0603"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This proposal is for the continuation and expansion of an underway program on the R/V Laurence M. Gould to measure dissolved carbon dioxide gas (pCO2) along with occasional total carbon dioxide (TCO2) in surface waters on transects of Drake Passage. The added observations include dissolved oxygen, as well as nutrient and carbon-13. The proposed work is similar to the underway measurement program made aboard R/V Nathaniel B. Palmer, and complements similar surface temperature and current data.\u003cbr/\u003eThe Southern Ocean is an important component of the global carbon budget. Low surface temperatures with consequently low vertical stability, ice formation, and high winds produce a very active environment for the exchange of gaseous carbon dioxide between the atmospheric and oceanic reservoirs. The Drake Passage is the narrowest point through which the Antarctic Circumpolar Current and its associated fronts must pass, and is the most efficient location for the measurement of latitudinal gradients of gas exchange. The generated time series will contribute towards two scientific goals: the quantification of the spatial and temporal variability and trends of surface carbon dioxide, oxygen, nutrients and C-13, and an understanding of the dominant processes that contribute to the observed variability.", "east": -61.4732, "geometry": "POINT(-64.73915 -58.81715)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.7573, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Takahashi, Taro", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.877, "title": "Collaborative Research: Processes Driving Spatial and Temporal Variability of Surface pCO2 in the Drake Passage", "uid": "p0000572", "west": -68.0051}, {"awards": "0632399 Jefferies, Stuart", "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": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere", "datasets": [{"dataset_uid": "600152", "doi": "10.15784/600152", "keywords": "Antarctica; Cosmos; Satellite Remote Sensing; Sun", "people": "Jefferies, Stuart M.", "repository": "USAP-DC", "science_program": null, "title": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere", "url": "https://www.usap-dc.org/view/dataset/600152"}], "date_created": "Wed, 10 Mar 2010 00:00:00 GMT", "description": "The proposal is to develop an instrument that can simultaneously measure the sound speed and magnetic fields at three heights in the solar atmosphere. The instrument will use magneto-optical filters tuned to the solar absorption lines at 422 nm (Ca I), 589 nm (Na D2), and 770 nm (K) to make measurements of Doppler velocities and longitudinal magnetic field. These lines form in the mid- and low-chromosphere and photosphere, respectively. In addition, the instrument will also use a Fabry-Perot etalon as a narrowband filter to measure the intensity variations of the 1083 nm (He I) line that is formed high in the chromosphere and which shows the location of the \"foot points\" of coronal holes. Together, the four lines will allow studying wave motions throughout the solar atmosphere. The instrument will record images of the Sun every 10 seconds with a spatial resolution of 1 arc-second. Thus, the project will be fostering the development of existing magneto-optical filter technology to a new level. Upon construction, the telescope will be tested at South Pole for a long period of uninterrupted observations. Both the local and global helioseismic analysis procedures will be utilized to identify and to characterize different types of waves present in the solar atmosphere. These observations will allow determining the structure and dynamics of the Sun\u0027s atmosphere through seismic measurements and, thus, improve the atmosphere models, assess the role of waves in heating the chromosphere/corona and driving the solar wind, and better understand how the Sun\u0027s atmosphere couples to the interior. The broader impact of the proposed project is two fold. First, there is a potential benefit to the science and to the society because it is believed that the solar atmosphere is a \"home\" to many phenomena that can have a direct effect on the solar activity, including flares, coronal mass ejections, and the solar wind. Understanding the structure and dynamics of the solar atmosphere will therefore lead to a better understanding of the Sun-Earth connection. The collected data will be made available to other researchers at DVDs. The broader audience of general public will be reached through presentations at high schools, libraries, and community events, and news articles in the general press. Most of the research materials will also be placed in the Web.", "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 Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Jefferies, Stuart M.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere", "uid": "p0000526", "west": -180.0}, {"awards": "0440666 Waddington, Edwin", "bounds_geometry": null, "dataset_titles": "Histories of Accumulation, Thickness, and WAIS Divide Location, Antarctica", "datasets": [{"dataset_uid": "609473", "doi": "10.7265/N5QR4V2J", "keywords": "Antarctica; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; WAIS Divide; WAIS Divide Ice Core", "people": "Koutnik, Michelle; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Histories of Accumulation, Thickness, and WAIS Divide Location, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609473"}], "date_created": "Thu, 04 Mar 2010 00:00:00 GMT", "description": "This award supports development of a new modeling approach that will extract information about past snow accumulation rate in both space and time in the vicinity of the future ice core near the Ross-Amundsen divide of the West Antarctic Ice Sheet (WAIS). Internal layers, detected by ice-penetrating radar, are isochrones, or former ice-sheet surfaces that have been buried by subsequent snowfall, and distorted by ice flow. Extensive ice-penetrating radar data are available over the inland portion of the WAIS. Layers have been dated back to 17,000 years before present. The radar data add the spatial dimension to the temporally resolved accumulation record from ice cores. Accumulation rates are traditionally derived from the depths of young, shallow layers, corrected for strain using a local 1-D ice-flow model. Older, deeper layers have been more affected by flow over large horizontal distances. However, it is these deeper layers that contain information on longer-term climate patterns. This project will use geophysical inverse theory and a 2.5D flow-band ice-flow forward model comprising ice-surface and layer-evolution modules, to extract robust transient accumulation patterns by assimilating multiple deeper, more-deformed layers that have previously been intractable. Histories of divide migration, geothermal flux, and surface evolution will also be produced. The grant will support the PhD research of a female graduate student who is a mentor to female socio-economically disadvantaged high-school students interested in science, through the University of Washington Women\u0027s Center. It will also provide a research\u003cbr/\u003eexperience for an undergraduate student, and contribute to a freshman seminar on Scientific Research.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS", "is_usap_dc": true, "keywords": "Ross-Amundsen Divide; FIELD SURVEYS; Internal Layers; Ice Flow Model; West Antarctic Ice Sheet; Accumulation; Glacier; Ice Penetrating Radar; Model; MODELS; Snow Accumulation; GPS; Antarctica; Isochron; Not provided; Snowfall; Radar", "locations": "West Antarctic Ice Sheet; Antarctica; Ross-Amundsen Divide", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Koutnik, Michelle; Waddington, Edwin D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e MODELS \u003e MODELS; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": null, "title": "Histories of accumulation, thickness and WAIS Divide location from radar layers using a new inverse approach", "uid": "p0000018", "west": null}, {"awards": "9980379 Baker, Ian", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 15 Feb 2010 00:00:00 GMT", "description": "This award is for support for three years of funding to study the effects of impurities on the flow of poly- crystalline ice. It has been known for thirty years that both hydrofluoric acid (HF) and hydrochloric acid (HCl) dramatically decrease the strength of ice and recent work by the author\u0027s group has shown that sulfuric acid (H2SO4) produces a similar reduction in strength. However, these data are for single crystals at strain rates and stresses that far exceed those found in glaciers and ice sheets, and often at concentrations that far exceed those in natural ice. Therefore, it is not known how impurities found in nature affect the flow of polycrystalline ice at slow strain rates. In this research, the effects of nitric acid and sulfuric acid (which are naturally occurring impurities in ice) on the microstructure (dislocation structure, grain boundary structure and location of the acids) and creep of polycrystalline ice (at a range of temperatures and stresses) will be determined. The ice\u0027s response to creep deformation will be studied using a combination of x-ray topography, optical microscopy and scanning electron microscopy. X-ray microanalysis in an environmental scanning electron microscope will be used to study the location of impurities. The structure and creep behavior of the acid-doped ice will be compared with those of both high-purity laboratory-grown ice and ice from Byrd Station, Antarctica. The end-result of this project will be to elucidate the effects of naturally-occurring acid impurities on the mechanical properties of polycrystalline ice under conditions relevant to the deformation of glaciers and ice sheets, including and understanding of how impurities affect the underlying deformation mechanisms.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e PARTICLE DETECTORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e SCANNING ELECTRON MICROSCOPES", "is_usap_dc": true, "keywords": "Ice Core Data; Ice Core; Microstructure; Ice Sheet; Ice Core Chemistry; Antarctic Ice Sheet; LABORATORY", "locations": "Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Baker, Ian; Obbard, Rachel", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "The Effects of Impurities on the Flow of Polycrystalline Ice", "uid": "p0000015", "west": null}, {"awards": "0440414 Steig, Eric", "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": "Stable Isotope Studies at East Antarctic US ITASE Sites", "datasets": [{"dataset_uid": "600042", "doi": "10.15784/600042", "keywords": "Antarctica; Atmosphere; Climate; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; ITASE; Meteorology; Paleoclimate; Satellite Remote Sensing; Weather Station Data", "people": "Steig, Eric J.", "repository": "USAP-DC", "science_program": "ITASE", "title": "Stable Isotope Studies at East Antarctic US ITASE Sites", "url": "https://www.usap-dc.org/view/dataset/600042"}], "date_created": "Mon, 14 Sep 2009 00:00:00 GMT", "description": "This award supports a project to obtain stable isotope profiles from shallow (\u003c100 m) ice cores from East Antarctica, to add to the growing database of environmental proxy data collected under the auspices of the \"ITASE\" (International TransAntarctic Scientific Expedition) program. In Antarctica, the instrumental record of climate is particularly short (~40 years except in a few isolated locations on the coast), and ice core proxy data are the only means available for extending this record into the past. The use of stable isotopes of water (18-O/16-O and D/H ratios) from ice cores as proxies for temperature is well established for both very short (i.e. seasonal) and long timescales (centuries, millennia). Using multivariate regression methods and shallow ice cores from West Antarctica, a reconstruction of Antarctic climate over the last ~150 years has been developed which suggests the continent has been warming, on average, at a rate of ~0.2 K/century. Further improving these reconstructions is the chief motivation for further extending the US ITASE project. Ten to fifteen shallow (~ 100 m) from Victoria Land, East Antarctica will be obtained and analyzed. The core will be collected along a traverse route beginning at Taylor Dome and ending at the South Pole. Age-depth relationships for the cores will be determined through a combination of stable isotopes, visual stratigraphy and seasonal chemical signatures and marker horizons. Reconstructions of Antarctic climate obtained from these cores will be incorporated into the global network of paleoclimate information, which has been important in science, policy and educational contexts. The project will include graduate student and postdoctoral training and field experience.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ITASE", "south": -90.0, "title": "Stable Isotope Studies at East Antarctic US ITASE Sites", "uid": "p0000202", "west": -180.0}, {"awards": "9814810 Bales, Roger", "bounds_geometry": "POLYGON((-124 -76,-120 -76,-116 -76,-112 -76,-108 -76,-104 -76,-100 -76,-96 -76,-92 -76,-88 -76,-84 -76,-84 -77.4,-84 -78.8,-84 -80.2,-84 -81.6,-84 -83,-84 -84.4,-84 -85.8,-84 -87.2,-84 -88.6,-84 -90,-88 -90,-92 -90,-96 -90,-100 -90,-104 -90,-108 -90,-112 -90,-116 -90,-120 -90,-124 -90,-124 -88.6,-124 -87.2,-124 -85.8,-124 -84.4,-124 -83,-124 -81.6,-124 -80.2,-124 -78.8,-124 -77.4,-124 -76))", "dataset_titles": "Atmospheric Mixing Ratios of Hydroperoxides above the West Antarctic Ice Sheet; Twenty-Three Century-scale Ice Core Records of Hydrogen Peroxide (H2O2) from West Antarctica", "datasets": [{"dataset_uid": "609392", "doi": "10.7265/N5TM7826", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; WAIS", "people": "Frey, Markus; Bales, Roger; McConnell, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Twenty-Three Century-scale Ice Core Records of Hydrogen Peroxide (H2O2) from West Antarctica", "url": "https://www.usap-dc.org/view/dataset/609392"}, {"dataset_uid": "609394", "doi": "10.7265/N5PZ56RS", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; ITASE; WAIS", "people": "Bales, Roger; Frey, Markus; McConnell, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Atmospheric Mixing Ratios of Hydroperoxides above the West Antarctic Ice Sheet", "url": "https://www.usap-dc.org/view/dataset/609394"}], "date_created": "Mon, 01 Jun 2009 00:00:00 GMT", "description": "This award supports a project to improve understanding of atmospheric photochemistry over West Antarctica, as recorded in snow, firn and ice. Atmospheric and firn sampling will be undertaken as part of the U.S. International Trans-Antarctic Scientific Expedition (US ITASE) traverses. Measurements of hydrogen peroxide (H2O2) and formaldehyde (HCHO) will be made on these samples and a recently developed, physically based atmosphere-to-snow transfer model will be used to relate photochemical model estimates of these components to the concentrations of these parameters in the atmosphere and snow. The efficiency of atmosphere-to-snow transfer and the preservation of these components is strongly related to the rate and timing of snow accumulation. This information will be obtained by analyzing the concentration of seasonally dependent species such as hydrogen peroxide, nitric acid and stable isotopes of oxygen. Collection of samples along the US ITASE traverses will allow sampling at a wide variety of locations, reflecting both a number of different depositional environments and covering much of the West Antarctic region.", "east": -84.0, "geometry": "POINT(-104 -83)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUORESCENCE SPECTROSCOPY; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS SENSORS", "is_usap_dc": true, "keywords": "Ice Core; Ice Core Chemistry; FIELD INVESTIGATION; FIELD SURVEYS; Antarctica; West Antarctica; Antarctic; LABORATORY; Ice Core Gas Records; Not provided; Ice Core Data; Polar Firn Air; Hydrogen Peroxide; West Antarctic Ice Sheet; Shallow Firn Air; US ITASE; Antarctic Ice Sheet; Snow Chemistry", "locations": "Antarctica; West Antarctica; Antarctic; Antarctic Ice Sheet; West Antarctic Ice Sheet", "north": -76.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Bales, Roger; Frey, Markus; McConnell, Joseph", "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": -90.0, "title": "Hydrogen Peroxide, Formaldehyde, and Sub-Annual Snow Accumulation in West Antarctica: Participation in West Antarctic Traverse", "uid": "p0000253", "west": -124.0}, {"awards": "0439759 Ballard, Grant", "bounds_geometry": "POLYGON((-180 -60,-177.5 -60,-175 -60,-172.5 -60,-170 -60,-167.5 -60,-165 -60,-162.5 -60,-160 -60,-157.5 -60,-155 -60,-155 -61.76,-155 -63.52,-155 -65.28,-155 -67.04,-155 -68.8,-155 -70.56,-155 -72.32,-155 -74.08,-155 -75.84,-155 -77.6,-157.5 -77.6,-160 -77.6,-162.5 -77.6,-165 -77.6,-167.5 -77.6,-170 -77.6,-172.5 -77.6,-175 -77.6,-177.5 -77.6,180 -77.6,178.5 -77.6,177 -77.6,175.5 -77.6,174 -77.6,172.5 -77.6,171 -77.6,169.5 -77.6,168 -77.6,166.5 -77.6,165 -77.6,165 -75.84,165 -74.08,165 -72.32,165 -70.56,165 -68.8,165 -67.04,165 -65.28,165 -63.52,165 -61.76,165 -60,166.5 -60,168 -60,169.5 -60,171 -60,172.5 -60,174 -60,175.5 -60,177 -60,178.5 -60,-180 -60))", "dataset_titles": "Access to data; Adelie penguin banding data 1994-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science; Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "datasets": [{"dataset_uid": "601443", "doi": "10.15784/601443", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Penguin; Ross Sea; Seabirds", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin banding data 1994-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601443"}, {"dataset_uid": "601444", "doi": "10.15784/601444", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Mark-Recapture; Monitoring; Penguin; Ross Island", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601444"}, {"dataset_uid": "001368", "doi": "", "keywords": null, "people": null, "repository": "CADC", "science_program": null, "title": "Access to data", "url": "http://data.prbo.org/apps/penguinscience/AllData/mammals"}], "date_created": "Tue, 19 May 2009 00:00:00 GMT", "description": "This project is an international collaborative investigation of geographic structuring, founding of new colonies, and population change of Adelie penguins (Pygoscelis adelia) nesting on Ross and Beaufort islands, Antarctica. The long-term changes occurring at these colonies are representative of changes throughout the Ross Sea, where 30% of all Adelie penguins reside, and are in some way related to changing climate. The recent grounding of two very large icebergs against Ross and Beaufort islands, with associated increased variability in sea-ice extent, has provided an unparalleled natural experiment affecting wild, interannual swings in colony productivity, foraging effort, philopatry and recruitment. Results of this natural experiment can provide insights into the demography and geographic population structuring of this species, having relevance Antarctic-wide in understanding its future responses to climate change as well as interpreting its amazingly well known Holocene history. This ongoing study will continue to consider the relative importance of resources that constrain or enhance colony growth (nesting habitat, access to food); the aspects of natural history that are affected by exploitative or interference competition among neighboring colonies (breeding success, foraging effort); climatic factors that influence the latter, especially sea ice patterns; and behavioral mechanisms that influence colony growth as a function of initial size and location (emigration, immigration). An increased effort will focus on understanding factors that affect over-winter survival. The hypothesis is that the age structure of Cape Crozier has changed over the past thirty years and no longer reflects the smaller colonies nearby. Based on recent analyses, it appears that the Ross Island penguins winter in a narrow band of sea ice north of the Antarctic Circle (where daylight persists) and south of the southern boundary of the Antarctic Circumpolar Current (where food abounds). More extensive winter ice takes the penguins north of that boundary where they incur higher mortality. Thus, where a penguin winters may be due to the timing of its post-breeding departure (which differs among colonies), which affects where it first encounters sea ice on which to molt and where it will be transported by the growing ice field. Foraging effort and interference competition for food suggested as factors driving the geographic structuring of colonies. The research includes a census of known-age penguins, studies of foraging effort and overlap among colonies; and identification of the location of molting and wintering areas. Information will be related to sea-ice conditions as quantified by satellite images. Demographic and foraging-effort models will be used to synthesize results. The iceberg natural experiment is an unparalleled opportunity to investigate the demographics of a polar seabird and its response to climate change. The marked, interannual variability in apparent philopatry, with concrete data being collected on its causes, is a condition rarely encountered among studies of vertebrates. Broader impacts include collaborating with New Zealand and Italian researchers, involving high school teachers and students in the fieldwork and continuing a website to highlight results to both scientists and the general public.", "east": -155.0, "geometry": "POINT(-175 -68.8)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ballard, Grant", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "CADC; USAP-DC", "science_programs": null, "south": -77.6, "title": "COLLABORATIVE: Geographic Structure of Adelie Penguin Colonies - Demography of Population Change", "uid": "p0000068", "west": 165.0}, {"awards": "0440478 Tang, Kam", "bounds_geometry": "POINT(166.66267 -77.85067)", "dataset_titles": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial Forms of Phaeocystis Antarctica", "datasets": [{"dataset_uid": "600043", "doi": "10.15784/600043", "keywords": "Biota; McMurdo Sound; Oceans; Phytoplankton; Ross Sea; Southern Ocean; Zooplankton", "people": "Tang, Kam; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial Forms of Phaeocystis Antarctica", "url": "https://www.usap-dc.org/view/dataset/600043"}], "date_created": "Mon, 04 May 2009 00:00:00 GMT", "description": "Phaeocystis Antarctica is a widely distributed phytoplankton that forms dense blooms and aggregates in the Southern Ocean. This phytoplankton and plays important roles in polar ecology and biogeochemistry, in part because it is a dominant primary producer, a main component of organic matter vertical fluxes, and the principal producer of volatile organic sulfur in the region. Yet P. Antarctica is also one of the lesser known species in terms of its physiology, life history and trophic relationships with other organisms; furthermore, information collected on other Phaeocystis species and from different locations may not be applicable to P. Antarctica in the Ross Sea. P. Antarctica occurs mainly as two morphotypes: solitary cells and mucilaginous colonies, which differ significantly in size, architecture and chemical composition. Relative dominance between solitary cells and colonies determines not only the size spectrum of the population, but also its carbon dynamics, nutrient uptake and utilization. Conventional thinking of the planktonic trophic processes is also challenged by the fact that colony formation could effectively alter the predator-prey interactions and interspecific competition. However, the factors that regulate the differences between solitary and colonial forms of P. Antarctica are not well-understood. The research objective of this proposal is therefore to address these over-arching questions:\u003cbr/\u003eo Do P. Antarctica solitary cells and colonies differ in growth, composition and\u003cbr/\u003ephotosynthetic rates?\u003cbr/\u003eo How do nutrients and grazers affect colony development and size distribution of P. \u003cbr/\u003eAntarctica?\u003cbr/\u003eo How do nutrients and grazers act synergistically to affect the long-term population\u003cbr/\u003edynamics of P. Antarctica? Experiments will be conducted in the McMurdo station with natural P. Antarctica assemblages and co-occurring grazers. Laboratory experiments will be conducted to study size-specific growth and photosynthetic rates of P. Antarctica, size-specific grazing mortality due to microzooplankton and mesozooplankton, the effects of macronutrients on the (nitrogen compounds) relative dominance of solitary cells and colonies, and the effects of micronutrient (Fe) and grazing related chemical signals on P. Antarctica colony development. Because this species is of critical importance in the Southern Ocean, and because this research will provide critical information on factors that regulate the role of P.Antarctica in food webs and biogeochemical cycles, a major gap in knowledge will be addressed. This project will train two marine science PhD students. The investigators will also collaborate with the School of Education and a marine science museum to communicate polar science to a broader audience.", "east": 166.66267, "geometry": "POINT(166.66267 -77.85067)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.85067, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Tang, Kam; Smith, Walker", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.85067, "title": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial forms of Phaeocystis antarctica", "uid": "p0000214", "west": 166.66267}, {"awards": "0438777 Fritts, 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": "Correlative Antarctic and Inter-Hemispheric Dynamics Studies Using the MF Radar at Rothera", "datasets": [{"dataset_uid": "600040", "doi": "10.15784/600040", "keywords": "Antarctica; Atmosphere; Meteorology; Radar", "people": "Fritts, David", "repository": "USAP-DC", "science_program": null, "title": "Correlative Antarctic and Inter-Hemispheric Dynamics Studies Using the MF Radar at Rothera", "url": "https://www.usap-dc.org/view/dataset/600040"}], "date_created": "Mon, 16 Mar 2009 00:00:00 GMT", "description": "This proposal is to continue operation and scientific studies with the middle-frequency (MF, 1-30 MHz) mesospheric radar deployed at the British Antarctic station Rothera in 1996. This system is now a key site in the Antarctic MF radar chain near 68 deg. S, which includes also MF radars at Syowa (Japan) and Davis (Australia) stations. This radar comprises the winds component of a developing instrument suite for the mesosphere-thermosphere (MLT) studies at Rothera - a focus of the new BAS 5-year plan, which also includes the Fe temperature lidar (formerly at South Pole) and the mesopause airglow imager for gravity wave studies (formerly at Halley). The Rothera MF radar has just had its antennas and electronics upgraded to achieve better signal-to-noise ratio and more continuous measurements in height and time. The main focus of the proposed research is to extend the knowledge of the polar mesosphere dynamics. The instrument suite at Rothera is ideally positioned for correlative interhemispheric studies with northern hemisphere sites at Poker Flat, Alaska (65 deg. N) and ALOMAR, Norway (69 deg. N) having comparable instrumentation. Further research efforts performed with continued funding will focus on: (1) multi-instrument collaborative studies at Rothera to quantify as fully as possible the dynamics, structure, and variability of the MLT at that location, (2) multi-site (and multi-instrument) studies of large-scale dynamics and variability in the Antarctic (together with the radars and other instrumentation at Davis and Syowa), and (3) interhemispheric studies employing instruments (e.g., the Na resonance lidar and MF radar) at Poker Flat and ALOMAR. It is expected that these studies will lead to a more detailed understanding of (1) mean, tidal, and planetary wave structures at polar latitudes, (2) seasonal, inter-annual, and short-term variability of these structures, (3) hemispheric differences in the tidal and planetary wave structures arising from different source and wave interaction conditions, and (4) the relative influences of gravity waves in the two hemispheres. Such studies will also contribute more generally to an increased awareness of the role of high-latitude processes in global atmospheric dynamics and variability.", "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 Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Fritts, David", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Correlative Antarctic and Inter-Hemispheric Dynamics Studies Using the MF Radar at Rothera", "uid": "p0000021", "west": -180.0}, {"awards": "0440759 Sowers, Todd; 0440498 White, James; 0440602 Saltzman, Eric; 0440509 Battle, Mark; 0440701 Severinghaus, Jeffrey; 0440615 Brook, Edward J.", "bounds_geometry": "POINT(-112.085 -79.467)", "dataset_titles": "Gases in Firn Air and Shallow Ice at the WAIS Drilling Site, Antarctica; Ice Core Air Carbonyl Sulfide Measurements - SPRESSO Ice Core; Methane Isotopes from the WAIS Divide Ice Core; Surface Temperature Reconstruction from Borehole Temperature Measurement in WDC05A; WAIS ice core Methane Data, Carbon Dioxide Data", "datasets": [{"dataset_uid": "609493", "doi": "10.7265/N5319SV3", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "people": "Sowers, Todd A.; McConnell, Joseph; Brook, Edward J.; Mitchell, Logan E; Taylor, Kendrick C.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS ice core Methane Data, Carbon Dioxide Data", "url": "https://www.usap-dc.org/view/dataset/609493"}, {"dataset_uid": "609435", "doi": "10.7265/N5J67DW0", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Isotope; Methane; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Methane Isotopes from the WAIS Divide Ice Core", "url": "https://www.usap-dc.org/view/dataset/609435"}, {"dataset_uid": "609638", "doi": "10.7265/N56971HF", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Temperature; WAIS Divide; WAIS Divide Ice Core", "people": "Orsi, Anais J.; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Surface Temperature Reconstruction from Borehole Temperature Measurement in WDC05A", "url": "https://www.usap-dc.org/view/dataset/609638"}, {"dataset_uid": "609412", "doi": "10.7265/N5251G40", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Snow/ice; Snow/Ice; WAIS Divide; WAIS Divide Ice Core", "people": "Saltzman, Eric", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Gases in Firn Air and Shallow Ice at the WAIS Drilling Site, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609412"}, {"dataset_uid": "601357", "doi": "10.15784/601357", "keywords": "Antarctica; Atmospheric Gases; Gas Measurement; Ice Core; Ice Core Gas Records; Trace Gases", "people": "Saltzman, Eric; Aydin, Murat", "repository": "USAP-DC", "science_program": null, "title": "Ice Core Air Carbonyl Sulfide Measurements - SPRESSO Ice Core", "url": "https://www.usap-dc.org/view/dataset/601357"}], "date_created": "Tue, 03 Feb 2009 00:00:00 GMT", "description": "This award supports a project to measure the elemental and isotopic composition of firn air and occluded air in shallow boreholes and ice cores from the WAIS Divide site, the location of a deep ice-coring program planned for 2006-07 and subsequent seasons. The three primary objectives are: 1) to establish the nature of firn air movement and trapping at the site to aid interpretations of gas data from the deep core; 2) to expand the suite of atmospheric trace gas species that can be measured in ice and replicate existing records of other species; and 3) to inter-calibrate all collaborating labs to insure that compositional and isotopic data sets are inter-comparable. The program will be initiated with a shallow drilling program during the 05/06 field season which will recover two 300+m cores and firn air samples. The ice core and firn air will provide more than 700 years of atmospheric history that will be used to address a number of important questions related to atmospheric change over this time period. The research team consists of six US laboratories that also plan to participate in the deep core program. This collaborative research program has a number of advantages. First, the scientists will be able to coordinate sample allocation a priori to maximize the resolution and overlap of records of interrelated species. Second, sample registration will be exact, allowing direct comparison of all records. Third, a coherent data set will be produced at the same time and all PI.s will participate in interpreting and publishing the results. This will insure that the best possible understanding of gas records at the WAIS Divide site will be achieved, and that all work necessary to interpret the deep core is conducted in a timely fashion. The collaborative structure created by the proposal will encourage sharing of techniques, equipment, and ideas between the laboratories. The research will identify impacts of various industrial/agricultural activities and help to distinguish them from natural variations, and will include species for which there are no long records of anthropogenic impact. The work will also help to predict future atmospheric loadings. The project will contribute to training scientists at several levels, including seven undergraduates, two graduate students and one post doctoral fellow.", "east": -112.085, "geometry": "POINT(-112.085 -79.467)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GC-MS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e SPECTROMETERS \u003e SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS; 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 TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS", "is_usap_dc": true, "keywords": "Ice Core Chemistry; WAIS Divide; Firn; LABORATORY; Ice Core; Firn Air Isotope Measurements; Shallow Firn Air; FIELD INVESTIGATION; Ice Core Gas Records; GROUND-BASED OBSERVATIONS; Firn Isotopes; Wais Divide-project; Gas Data; Polar Firn Air; Not provided; Trace Gas Species; Trapped Gases; West Antarctic Ice Sheet; Deep Core; Ice Sheet; Gas; Firn Air Isotopes; FIELD SURVEYS; Air Samples; Atmospheric Gases; Isotope; Cores; Atmosphere; Ice Core Data; Surface Temperatures; Firn Air; Borehole; Antarctica", "locations": "West Antarctic Ice Sheet; Antarctica; WAIS Divide", "north": -79.467, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Battle, Mark; Mischler, John; Saltzman, Eric; Aydin, Murat; White, James; Brook, Edward J.; Orsi, Anais J.; Severinghaus, Jeffrey P.; Sowers, Todd A.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.467, "title": "Collaborative Research: Gases in Firn Air and Shallow Ice at the Proposed WAIS Divide Drilling Site", "uid": "p0000368", "west": -112.085}, {"awards": "0229546 MacAyeal, Douglas", "bounds_geometry": "POINT(-178 -78)", "dataset_titles": "collection of nascent rift images and description of station deployment; Continuous GPS (static) Data from the Ross Ice Shelf, Antarctica; Giant Icebergs of the Ross Sea, in situ Drift and Weather Measurements, Antarctica; Iceberg Firn Temperatures, Antarctica; Iceberg Harmonic Tremor, Seismometer Data, Antarctica; Iceberg Satellite imagery from stations and ice shelves (full data link not provided); Iceberg Tiltmeter Measurements, Antarctica; Ice Shelf Rift Time-Lapse Photography, Antarctica; Incorporated Research Institutions for Seismology; Nascent Iceberg Webcam Images available during the deployment period; Ross Ice Shelf Firn Temperature, Antarctica; The files contain a short header (number of data samples, sample rate, start time, stop time, channel title)The time series data then follow the header above.; This site mirrors the NSIDC website archive.", "datasets": [{"dataset_uid": "609352", "doi": "10.7265/N5M61H55", "keywords": "Glaciology; Iceberg; Oceans; Ross Ice Shelf; Sea Ice; Snow/ice; Snow/Ice; Southern Ocean; Temperature", "people": "MacAyeal, Douglas; Sergienko, Olga; Thom, Jonathan", "repository": "USAP-DC", "science_program": null, "title": "Iceberg Firn Temperatures, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609352"}, {"dataset_uid": "609350", "doi": "10.7265/N5VM496K", "keywords": "AWS; Glaciology; GPS; Iceberg; Meteorology; Oceans; Ross Sea; Sea Ice; Southern Ocean; Weatherstation", "people": "Bassis, Jeremy; Aster, Richard; Okal, Emile; MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Giant Icebergs of the Ross Sea, in situ Drift and Weather Measurements, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609350"}, {"dataset_uid": "609351", "doi": "10.7265/N5QV3JGV", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Photo/video; Photo/Video; Ross Ice Shelf", "people": "Brunt, Kelly; MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Ice Shelf Rift Time-Lapse Photography, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609351"}, {"dataset_uid": "609347", "doi": "10.7265/N57W694M", "keywords": "Antarctica; Geodesy; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ross Ice Shelf; Southern Ocean", "people": "Brunt, Kelly; MacAyeal, Douglas; King, Matthew", "repository": "USAP-DC", "science_program": null, "title": "Continuous GPS (static) Data from the Ross Ice Shelf, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609347"}, {"dataset_uid": "001684", "doi": "", "keywords": null, "people": null, "repository": "AMRDC", "science_program": null, "title": "This site mirrors the NSIDC website archive.", "url": "http://uwamrc.ssec.wisc.edu/"}, {"dataset_uid": "609353", "doi": "10.7265/N5GF0RFF", "keywords": "Glaciology; Iceberg; Oceans; Ross Ice Shelf; Sea Ice; Southern Ocean; Tiltmeter", "people": "Kim, Young-Jin; MacAyeal, Douglas; Bliss, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Iceberg Tiltmeter Measurements, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609353"}, {"dataset_uid": "609354", "doi": "10.7265/N5BP00Q3", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ross Ice Shelf; Snow/ice; Snow/Ice; Temperature", "people": "Scambos, Ted; Sergienko, Olga; Muto, Atsu; MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Ross Ice Shelf Firn Temperature, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609354"}, {"dataset_uid": "002568", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Iceberg Satellite imagery from stations and ice shelves (full data link not provided)", "url": "http://amrc.ssec.wisc.edu/"}, {"dataset_uid": "001598", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "The files contain a short header (number of data samples, sample rate, start time, stop time, channel title)The time series data then follow the header above.", "url": "http://nsidc.org"}, {"dataset_uid": "002504", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Nascent Iceberg Webcam Images available during the deployment period", "url": "https://amrc.ssec.wisc.edu/data/iceberg.html"}, {"dataset_uid": "001639", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "collection of nascent rift images and description of station deployment", "url": "http://thistle.org/nascent/index.shtml"}, {"dataset_uid": "609349", "doi": "10.7265/N5445JD6", "keywords": "Geology/Geophysics - Other; Glaciology; Iceberg; Oceans; Ross Sea; Sea Ice; Seismometer; Southern Ocean", "people": "Bassis, Jeremy; Aster, Richard; Okal, Emile; MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Iceberg Harmonic Tremor, Seismometer Data, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609349"}, {"dataset_uid": "001685", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Incorporated Research Institutions for Seismology", "url": "http://www.iris.edu/data/sources.htm"}], "date_created": "Fri, 19 Sep 2008 00:00:00 GMT", "description": "This award supports the study of the drift and break-up of Earth\u0027s largest icebergs, which were recently released into the Ross Sea of Antarctica as a result of calving from the Ross Ice Shelf. The scientific goals of the study are to determine the physics of iceberg motion within the dynamic context of ocean currents, winds, and sea ice, which determine the forces that drive iceberg motion, and the relationship between the iceberg and geographically and topographically determined pinning points on which the iceberg can ground. In addition, the processes by which icebergs influence the local environments (e.g., sea ice conditions near Antarctica, access to penguin rookeries, air-sea heat exchange and upwelling at iceberg margins, nutrient fluxes) will be studied. The processes by which icebergs generate globally far-reaching ocean acoustic signals that are detected within the global seismic (earthquake) sensing networks will also be studied. A featured element of the scientific research activity will be a field effort to deploy automatic weather stations, seismometer arrays and GPS-tracking stations on several of the largest icebergs presently adrift, or about to be adrift, in the Ross Sea. Data generated and relayed via satellite to home institutions in the Midwest will motivate theoretical analysis and computer simulation; and will be archived on an \"iceberg\" website (http://amrc.ssec.wisc.edu/amrc/iceberg.html) for access by scientists and the general public. At the most broad level, the study is justified by the fact that icebergs released by the Antarctic ice sheet represent the largest movements of fresh water within the natural environment (e.g., several of the icebergs to be studied, B15, C19 and others calved since 2000 CE, represent over 6000 cubic kilometers of fresh water-an amount roughly equivalent to 100 years of the flow of the Nile River). A better understanding of the impact of iceberg drift through the environment, and particularly the impact on ocean stratification and mixing, is essential to the understanding of the abrupt global climate changes witnessed by proxy during the ice age and of concern under conditions of future greenhouse warming. On a more specific level, the study will generate a knowledge base useful for the better management of Antarctic logistical resources (e.g., the shipping lanes to McMurdo Station) that can occasionally be influenced by adverse effects icebergs have on sea ice conditions.", "east": -178.0, "geometry": "POINT(-178 -78)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e HUMIDITY SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e MMS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e TEMPERATURE LOGGERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e TEMPERATURE PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS", "is_usap_dc": true, "keywords": "SEISMOLOGICAL STATIONS; Pressure; AWS; Velocity Measurements; Firn Temperature Measurements; Ice Velocity; Seismology; Ice Sheet Elevation; Harmonic Tremor; Ice Shelf Temperature; Wind Speed; Iceberg; Ice Surface Elevation; Non-Volcanic Tremor; Not provided; Antarctic; Iceberg Tremor; Solar Radiation; Antarctic Ice Sheet; Ross Ice Shelf; Elevation; GPS; Temperature Profiles; Ice Shelf Rift Camera; GROUND STATIONS; Latitude; GROUND-BASED OBSERVATIONS; Ice Shelf Weather; FIELD INVESTIGATION; ARWS; Surface Elevation; Ice Shelf Flow; Antarctica; FIELD SURVEYS; Camera; Seismometer; Iceberg Weather (aws); Ice Movement; Photo; Wind Direction; Iceberg Snow Accumulation; Tremor And Slow Slip Events; AWS Climate Data; Location; Iceberg Drift; Iceberg Collisions; Iceberg Tilt; Atmospheric Pressure; Iceberg Seismicity; Firn Temperature", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet; Ross Ice Shelf", "north": -78.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Okal, Emile; Aster, Richard; Bassis, Jeremy; Kim, Young-Jin; Bliss, Andrew; Sergienko, Olga; Thom, Jonathan; Scambos, Ted; Muto, Atsu; Brunt, Kelly; King, Matthew; Parker, Tim; Okal, Marianne; Cathles, Mac; MacAyeal, Douglas", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e ARWS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e SEISMOLOGICAL STATIONS; Not provided; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "AMRDC; IRIS; NSIDC; Project website; USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research of Earth\u0027s Largest Icebergs", "uid": "p0000117", "west": -178.0}, {"awards": "0338267 Gooseff, Michael", "bounds_geometry": "POLYGON((161.6 -77.4,161.773 -77.4,161.946 -77.4,162.119 -77.4,162.292 -77.4,162.465 -77.4,162.638 -77.4,162.811 -77.4,162.984 -77.4,163.157 -77.4,163.33 -77.4,163.33 -77.435,163.33 -77.47,163.33 -77.505,163.33 -77.54,163.33 -77.575,163.33 -77.61,163.33 -77.645,163.33 -77.68,163.33 -77.715,163.33 -77.75,163.157 -77.75,162.984 -77.75,162.811 -77.75,162.638 -77.75,162.465 -77.75,162.292 -77.75,162.119 -77.75,161.946 -77.75,161.773 -77.75,161.6 -77.75,161.6 -77.715,161.6 -77.68,161.6 -77.645,161.6 -77.61,161.6 -77.575,161.6 -77.54,161.6 -77.505,161.6 -77.47,161.6 -77.435,161.6 -77.4))", "dataset_titles": "Antarctic Hydrologic Margin Microbiology and Biogeochemistry - data; Hydrologic Margins Research Project, 2004-2008, McMurdo Dry Valleys", "datasets": [{"dataset_uid": "000238", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Antarctic Hydrologic Margin Microbiology and Biogeochemistry - data", "url": "http://water.engr.psu.edu/gooseff/web_antarctica/data.html"}, {"dataset_uid": "600016", "doi": "", "keywords": null, "people": "Gooseff, Michael N.", "repository": "USAP-DC", "science_program": null, "title": "Hydrologic Margins Research Project, 2004-2008, McMurdo Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/600016"}], "date_created": "Thu, 11 Sep 2008 00:00:00 GMT", "description": "Aquatic-terrestrial transition zones are crucial environments in understanding the biogeochemistry of landscapes. In temperate watersheds, these areas are generally dominated by riparian zones, which have been identified as regions of special interest for biogeochemistry because of the increased microbial activity in these locations, and because of the importance of these hydrological margins in facilitating and buffering hydrologic and biogeochemical exchanges between terrestrial and aquatic ecosystems. In the Antarctic Dry Valleys, terrestrial-aquatic transition zones are intriguing landscape features because of the vast importance of water in this polar desert, and because the material and energy budgets of dry valley ecosystems are linked by hydrology. Hydrological margins in aquatic-terrestrial transition zones will be studied in the Dry Valleys of Antarctica to answer two overarching questions: (1) what are the major controls over hydrologic and biogeochemical exchange across aquaticterrestrial transition zones and (2) to what extent do trends in nutrient cycling (e.g. nitrogen cycling) across these transition zones reflect differences in microbial communities or function vs. differences in the physical and chemical environment (e.g., redox potential)? The hydrologic gradients that define these interfaces provide the opportunity to assess the relative influence of physical conditions and microbial biodiversity and functioning upon biogeochemical cycling. Coordinated hydrologic, biogeochemical, and molecular microbial studies will be executed within hydrologic margins with the following research objectives: to determine the role of sediment characteristics, permafrost and active layer dynamics, and topography on sub-surface water content and distribution in hydrologic margins, to determine the extent to which transformations of nitrogen in hydrological margins are influenced by physical conditions (i.e., moisture, redox potential and pH) or by the presence of specific microbial communities (e.g., denitrifiers), and to characterize the microbial community structure and function of saturated zones.\u003cbr/\u003e\u003cbr/\u003eThis proposed research will provide an improved understanding of the interaction of liquid water, soils, microbial communities, and biogeochemistry within the important hydrologic margin landscape units of the dry valleys. Dry valleys streams and lakes are unique because there is no influence of higher vegetation on the movement of water and may therefore provide a model system for understanding physical and hydrological influences on microbial ecology and biogeochemistry. Hence the findings will contribute to Antarctic science as well as the broader study of riparian zones and hydrologic margins worldwide. Graduate students and undergraduate students will be involved with fieldwork and research projects. Information will be disseminated through a project web site, and outreach activities will include science education in local elementary, middle and high schools near the three universities involved.", "east": 163.33, "geometry": "POINT(162.465 -77.575)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -77.4, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gooseff, Michael N.; Barrett, John; Takacs-Vesbach, Cristina", "platforms": "Not provided", "repo": "PI website", "repositories": "PI website; USAP-DC", "science_programs": null, "south": -77.75, "title": "Collaborative Research: Hydrologic Controls over Biogeochemistry and Microbial Community Structure and Function across Terrestrial/Aquatic Interfaces in a Polar Desert", "uid": "p0000340", "west": 161.6}, {"awards": "0536870 Rogers, Scott", "bounds_geometry": "POINT(-106.8 -72.4667)", "dataset_titles": "Comprehensive Biological Study of Vostok Accretion Ice", "datasets": [{"dataset_uid": "600052", "doi": "10.15784/600052", "keywords": "Antarctica; Biota; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hydrothermal Vent; Lake Vostok; Microbes; Subglacial Lake", "people": "Rogers, Scott O.", "repository": "USAP-DC", "science_program": null, "title": "Comprehensive Biological Study of Vostok Accretion Ice", "url": "https://www.usap-dc.org/view/dataset/600052"}], "date_created": "Tue, 02 Sep 2008 00:00:00 GMT", "description": "The large subglacial Lake Vostok in Antarctica is unique ecological site with a novel microbial biota. The temperatures, pressures and lack of light all select for organisms that may not exist anywhere else on Earth. The accretion ice (lake water frozen to the bottom of the lower surface of the glacier) has preserved microbial samples from each region of Lake Vostok as the glacier passes over and into the lake. Thus, without contaminating the lake with microorganisms from the surface, microbes originating from the lake can be collected, transported to the laboratory and studied. Two of the deepest ice cores sections in this project are part of the international allocation. The will be shared between four researchers (Sergey Bulat from Russia, Jean-Robert Petit and Daniel Prieur from France, Scott Rogers from USA). The United States team will study, isolate, and characterize bacteria, fungi, and viruses that have been sampled from the lake through the process of ice accretion to the lower surface of 3500+m thick glacier overriding the lake. The project will involve a suite of methods, including molecular, morphological, and cultural. This includes observation and description by fluorescence, light, and electron microscopy, isolation on thirteen separate cultural media, polymerase chain reaction amplification, DNA sequencing, and phylogenetic analyses. Eleven accretion ice core sections, as well as two glacial ice core sections. As well as two glacial ice core sections will be studied. The accretion ice core sections, as well as two glacial ice core sections will be studied. The accretion ice core sections represent all of the major regions of the lake that have been sampled by the accretion process in the vicinity of the Vostok 5G ice core. The broader impacts of the work relate to the impact the results will have on the filed. These long=isolated lakes, deep below the Antarctic ice sheet may contain novel uniquely adapted organisms. Glacial ice contains an enormous diversity of entrapped microbes, some of which may be metabolically active in the ice. The microbes from Lake Vostok are of special interest, since they are adapted to cold, dark, and high pressure. Thus, their enzyme systems and biochemical pathways may be significantly different from those in the microbes that are the subject of current studies. As such, these organisms may form compounds that may have useful applications. Also, study of the accretion ice, and eventually the water, from Lake Vostok will provide a basis for the study of other subglacial lakes. Additionally, study of the microbes in the accretion ice will be useful to those planning to study analogous systems on ice-covered planets and moons.", "east": -106.8, "geometry": "POINT(-106.8 -72.4667)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -72.4667, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rogers, Scott O.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.4667, "title": "Comprehensive Biological Study of Vostok Accretion Ice", "uid": "p0000566", "west": -106.8}, {"awards": "0127022 Jeffrey, Wade", "bounds_geometry": "POLYGON((-177.639 -43.5676,-143.1091 -43.5676,-108.5792 -43.5676,-74.0493 -43.5676,-39.5194 -43.5676,-4.9895 -43.5676,29.5404 -43.5676,64.0703 -43.5676,98.6002 -43.5676,133.1301 -43.5676,167.66 -43.5676,167.66 -46.99877,167.66 -50.42994,167.66 -53.86111,167.66 -57.29228,167.66 -60.72345,167.66 -64.15462,167.66 -67.58579,167.66 -71.01696,167.66 -74.44813,167.66 -77.8793,133.1301 -77.8793,98.6002 -77.8793,64.0703 -77.8793,29.5404 -77.8793,-4.9895 -77.8793,-39.5194 -77.8793,-74.0493 -77.8793,-108.5792 -77.8793,-143.1091 -77.8793,-177.639 -77.8793,-177.639 -74.44813,-177.639 -71.01696,-177.639 -67.58579,-177.639 -64.15462,-177.639 -60.72345,-177.639 -57.29228,-177.639 -53.86111,-177.639 -50.42994,-177.639 -46.99877,-177.639 -43.5676))", "dataset_titles": "Expedition Data; Ross Sea microbial biomass and production", "datasets": [{"dataset_uid": "600029", "doi": "10.15784/600029", "keywords": "Biota; Chemistry:fluid; Chemistry:Fluid; CTD Data; Microbiology; Oceans; Phytoplankton; Ross Sea; Southern Ocean", "people": "Jeffrey, Wade H.", "repository": "USAP-DC", "science_program": null, "title": "Ross Sea microbial biomass and production", "url": "https://www.usap-dc.org/view/dataset/600029"}, {"dataset_uid": "001584", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0508"}, {"dataset_uid": "001690", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304B"}], "date_created": "Thu, 12 Jun 2008 00:00:00 GMT", "description": "Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea.", "east": 167.66, "geometry": "POINT(-4.9895 -60.72345)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUORESCENCE MICROSCOPY; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e GO-FLO BOTTLES", "is_usap_dc": true, "keywords": "R/V NBP; B-15J", "locations": "B-15J", "north": -43.5676, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Jeffrey, Wade H.; Neale, Patrick", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -77.8793, "title": "Collaborative Proposal: Interactive Effects of UV Radiation and Vertical Mixing on Phytoplankton and Bacterial Productivity of Ross See Phaeocystis Blooms", "uid": "p0000578", "west": -177.639}, {"awards": "0440609 Price, P. Buford", "bounds_geometry": "POINT(-112.06556 -79.469444)", "dataset_titles": null, "datasets": null, "date_created": "Tue, 03 Jun 2008 00:00:00 GMT", "description": "This award supports a project to use three downhole instruments - an optical logger; a\u003cbr/\u003eminiaturized biospectral logger at 420 nm (miniBSL-420); and an Acoustic TeleViewer (ATV) - to log a 350-m borehole at the WAIS Divide drill site. In addition, miniBSL-224 (at 224 nm) and miniBSL-420 will scan ice core sections at NICL to look for abrupt climate changes, volcanic ash, microbial concentrations, and correlations among them. Using the optical logger and ATV to log bubble number densities vs depth in a WAIS Divide borehole, we will detect annual layers, from which we can establish the age vs depth relation to the bottom of the borehole that will be available during the three-year grant period. With the same instruments we will search for long-period modulation of bubble and dust concentrations in order to provide definitive evidence for or against an effect of long-period variability of the sun or solar wind on climate. We will detect and accurately date ash layers in a WAIS Divide borehole. We will match them with ash layers that we previously detected in the Siple Dome borehole, and also match them with sulfate and ash layers found by others at Vostok, Dome Fuji, Dome C, and GISP2. The expected new data will allow us to extend our recent study which showed that the Antarctic record of volcanism correlates with abrupt climate change at a 95% to \u003e99.8% significance level and that the volcanic signatures at bipolar locations match at better than 3 sigma during the interval 2 to 45 kiloyears. The results to be obtained during this grant period will position us to extend an accurate age vs depth relation and volcano-climate correlations to earlier than 150 kiloyears ago in the future WAIS Divide borehole to be drilled to bedrock. Using the miniBSLs to identify biomolecules via their fluorescence, we will log a 350-m borehole at WAIS Divide, and we will scan selected lengths of ice core at NICL. Among the biomolecules the miniBSLs can identify will be chlorophyll, which will provide the first map of aerobic microbes in ice, and F420, which will provide the first map of methanogens in ice. We will collaborate with others in relating results from WAIS Divide and NICL ice cores to broader topics in climatology, volcanology, and microbial ecology. We will continue to give broad training to undergraduate and graduate students, to attract underrepresented minorities to science, engineering, and math, and to educate the press and college teachers. A deeper understanding of the causes of abrupt climate change, including a causal relationship with strong volcanic eruptions, can enable us to understand and mitigate adverse effects on climate.", "east": -112.06556, "geometry": "POINT(-112.06556 -79.469444)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUORESCENCE SPECTROSCOPY; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e OPTICAL DUST LOGGERS", "is_usap_dc": false, "keywords": "Volcanic Ash; Dust Concentration; Antarctica; FIELD INVESTIGATION; Liquid Veins In Ice; Optical Logger; Borehole; Ash Layer; FIELD SURVEYS; Microbial Metabolism; Climate; Biospectral Logger; Not provided; Protein Fluorescence; Gas Artifacts; Aerosol Fluorescence; Volcanism; WAIS Divide; Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.469444, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bay, Ryan; Price, Buford", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repositories": null, "science_programs": null, "south": -79.469444, "title": "Climatology, Volcanism, and Microbial Life in Ice with Downhole Loggers", "uid": "p0000746", "west": -112.06556}, {"awards": "0636899 Mende, Stephen", "bounds_geometry": null, "dataset_titles": "Antarctic Auroral Imaging", "datasets": [{"dataset_uid": "600070", "doi": "10.15784/600070", "keywords": "Antarctica; Atmosphere; Aurora; Cosmos; Photo/video; Photo/Video", "people": "Frey, Harald; Mende, Stephen", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Auroral Imaging", "url": "https://www.usap-dc.org/view/dataset/600070"}], "date_created": "Tue, 01 Apr 2008 00:00:00 GMT", "description": "The proposed work would modify an existing 4-channel all-sky camera at South Pole in order to observe several types of auroras, and to distinguish the cusp reconnection aurora from the normal plasma sheet precipitation. The camera will simultaneously operate in four wavelength regions that allow a distinction between auroras that are created by higher energy electrons (\u003e 1 keV) and those created by low energy (\u003c500 eV) precipitation. The cusp is the location where plasma enters the magnetosphere through the process of magnetic reconnection. This reconnection occurs where the Interplanetary Magnetic Field (IMF) and the terrestrial magnetic field are oriented in opposite directions. Using the IMAGE (Imager for Magnetopause to Aurora Global Exploration) satellite ultraviolet optical data it has been shown that cusp precipitation can be seen in different regions, which depend on the orientation of the IMF. South Pole station is uniquely located for optical observations of the aurora because of the 24 hours of darkness during austral winter and the appearance of the auroral oval within the field of view of all-sky cameras.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Mende, Stephen; Frey, Harald", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Antarctic Auroral Imaging", "uid": "p0000361", "west": null}, {"awards": "9980452 Harvey, Ralph", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 20 Mar 2008 00:00:00 GMT", "description": "9980452 Harvey This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for continuation of the Antarctic Search for Meteorites (ANSMET). Since 1976, ANSMET has recovered more than 10,000 meteorite specimens from locations along the Transantarctic Mountains. This award supports continued recovery of Antarctic meteorites during six successive austral summer field seasons, starting with the 2000-2001 season and ending with the 2005-2006 season. Under this project, systematic searches for meteorite specimens will take place at previously discovered stranding surfaces, and reconnaissance work will be conducted to discover and explore the extent of new areas with meteorite concentrations. ANSMET recovery teams will deploy by air to locations in the deep field for periods of 5-7 weeks. While at the meteorite stranding surface, field team members will search the ice visually, traversing on foot or on snowmobile. Specimens will be collected under the most sterile conditions practical and samples will remain frozen until returned to the Johnson Space Center (JSC) in Houston, Texas. At the JSC, initial characterization and sample distribution to all interested researchers takes place under the auspices of an interagency agreement between NSF, NASA, and the Smithsonian Institution. The impact of ANSMET has been substantial and this will continue under this award. The meteorites recovered by ANSMET are the best and most reliable source of new, non-microscopic extraterrestrial material, providing essential \"ground-truth\" concerning the materials that make up the asteroids, planets and other bodies of our solar system. The system for their characterization and distribution is unparalleled and their subsequent study has fundamentally changed our understanding of the solar system. ANSMET meteorites have helped researchers explore the conditions that were present in the nebula from which our solar system was born 4.556 billion years ago and provided samples of asteroids, ranging from primitive bodies unchanged since the formation of the solar system to complex, geologically active miniature planets. ANSMET samples proved, against the conventional wisdom, that some meteorites actually represent planetary materials, delivered to us from the Moon and Mars, completely changing our view of the geology of those bodies. ANSMET meteorites have even generated a new kind of inquiry into one of the most fundamental scientific questions possible; the question of biological activity in the universe as a whole. Over the past twenty years, ANSMET meteorites have economically provided a continuous and readily available supply of extraterrestrial materials for research, and should continue to do so in the future.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": false, "keywords": "FIELD SURVEYS; FIELD INVESTIGATION", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Harvey, Ralph", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "The Antarctic Search for Meteorites", "uid": "p0000118", "west": null}, {"awards": "9909436 Farley, Kenneth", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 11 Jul 2007 00:00:00 GMT", "description": "9909436 Farley This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an investigation of the uplift history of the Dry Valleys segment of the Transantarctic Mountains. The overall goal is to further constrain the exhumation history of the Transantarctic Mountains by using the newly developed apatite (U-Th)/He dating method on samples collected in vertical profiles. This approach, combined with existing apatite fission track information will constrain the rate and patterns of exhumation across the Transantarctic Mountains since their inception as a rift-flank uplift in the early Cenozoic. This project will complement other projects and build on previous interpretations of the exhumation and tectonic history determined using apatite fission track thermochronology. It will bridge the gap between information on erosion rates determined from fission track thermochronology and from cosmogenic surface exposure dating and integrate the exhumation history of the mountains with their landscape evolution. As such, the results from this project will address an outstanding problem in Antarctic science; namely the stability of the East Antarctic Ice Sheet, and the timing of the transition from a \"warm\" dynamic ice sheet to a cold polar ice sheet. Highly relevant to this issue is the landscape evolution of the Transantarctic Mountains because many diverse lines of evidence for the rate of landscape evolution have been used to argue for a dynamic ice sheet up until either the Pliocene (the \"dynamic\" ice sheet model) or the middle Miocene (the \"stable\" ice sheet model). Understanding the past stability or dynamic fluctuations of the East Antarctic ice sheet with respect to the climate record is, of course, important for understanding how the present ice sheet may respond to global warming. The specific objective of this project is to determine apatite (U-Th)/He age versus elevation trends for a number of vertical profiles from locations within the Transantarctic Mountain front and across the structural grain of the range. Fission track data already exist for all of these profiles, with apatite fission track ages ranging from 150-30 Ma. The greater precision of the (U-Th)/He technique and the fact it records information at lower temperatures (closure temperature of ~70 degrees Celsius; limits of 40-85 degrees Celsius for the He partial retention zone) will allow examination of the exhumation history of the TAM in more detail from ca 130 Ma to ~20 Ma. Another facet is to examine areas where Cretaceous exhumation is recorded and areas where the fission track profiles indicate periods of thermal and tectonic stability and minimal erosion throughout the Cretaceous. The variation of timing of the onset of more rapid exhumation accompanying uplift and formation of the Transantarctic Mountains in the early Cenozoic will also be examined.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Farley, Kenneth", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Exhumation of the Transantarctic Mountains: Constraints from (U-Th)/He Dating of Apatites", "uid": "p0000281", "west": null}, {"awards": "0125754 Hulbe, Christina", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 07 Jun 2007 00:00:00 GMT", "description": "This award supports a project to develop computational models to simulate ice-shelf rift propagation using a combination of well-established ice-shelf creep-flow models and new crevasse models, based on linear elastic fracture mechanics (LEFM). The overall objective of the proposed work is to simulate rift propagation and eventual large iceberg calving,and place those processes within a larger ice sheet and climate context. The work will proceed in stages, first developing models of single-and multiple-crevasse propagation; then using those models to evaluate propagation sensitivity to various environmental conditions; and third developing models that incorporate both crevasse propagation and advection within an ice- shelf system. Model development will be guided by and evaluated according to satellite observations of rift propagation in several characteristic locations on Antarctic ice shelves. New numerical models of fracture in ice will have applications to many problems in glaciology. The research proposed here is directed toward large rift formation in ice shelves and subsequent iceberg calving. It is motivated by the need to understand observed changes in modern ice shelves,and their connection to climate. Where it has been sampled, the sedimentary record of the Weddell Sea sector implies Peninsular ice shelf variability on millennial time scales. The ability to simulate iceberg calving in a credible way will improve our ability to reproduce such events and place the complete cycle of ice shelf advance and retreat in an ice-dynamics context. That will, in turn, enable us to place ice-shelf cycles within the climate cycles that ultimately drive ice-sheet mass balance.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hulbe, Christina", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Ice-Shelf Rift Propagation: Computational Simulation Using a Fracture Fracture Mechanics Approach", "uid": "p0000270", "west": null}, {"awards": "0230149 McGwire, Kenneth", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 04 Jun 2007 00:00:00 GMT", "description": "This award supports the development of novel methods for digital image analysis of glacial ice cores that are stored at the National Ice Core Laboratory (NICL) in Denver, Colorado. Ice cores are a critical source of information on how Earth has changed over time, since indicators of local climate (snow accumulation, temperature), regional characteristics (wind-blown materials such as sea salt, dust and pollen), global processes (e.g., CO2, methane), and even extraterrestrial influences (cosmogenic isotopes) are stored in the ice on a common time scale. This project will develop a high-resolution optical scanning system for laboratory curation of ice core images, internet-based search and retrieval capabilities, a digital image analysis system specifically for ice core studies, and methods to integrate ice core image analysis with other dating methods. These tools will be developed and tested in conjunction with scientific investigations of NICL holdings. Optical scanning and analysis tools will improve understanding of the historical development of the ice collected from a particular location and will help to resolve challenges such as ice that has lost stratigraphic order through flow processes. \u003cbr/\u003eBy providing permanent online digital archives of ice core images, this project will greatly improve the documentation and availability of ice core data while reducing time and costs for subsequent scientific investigations. Using the internet, ice core scientists will be able to determine the appropriateness of specific NICL holdings for various scientific studies. By optically scanning ice cores as they are processed at NICL, any researcher will be able to examine an ice core in similar detail to the few investigators who were fortunate enough to observe it before modifications from sampling and storage. Re-examination of cores could be done decades later by anyone at any location, which is not possible now because only the interpretation of the original observer is recorded. Integration of digital image data into ice core analysis will speed discovery, allow collaborative interpretation, and enhance consistency of analysis to improve ice core dating, identification of melt layers, location of flow disturbances, and more. The equipment will be housed at NICL and will be available to the broad community, improving scientific infrastructure.\u003cbr/\u003eThis work will also have numerous broader impacts. Ice core science addresses fundamental questions of human interest related to global warming, abrupt climate change, biogeochemical cycling, and more. The principal investigators broadly disseminate their scientific findings through numerous outlets, ranging from meeting with government officials, chairing and serving on NRC panels, writing popular books and articles, publishing in scientific literature, teaching classes, talking to civic groups, and appearing on radio and television. The results from ice core analyses have directly informed policymakers and will continue to do so. Thus, by improving ice core science, this projectl will benefit society.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e VISUAL OBSERVATIONS", "is_usap_dc": false, "keywords": "Image; Ice Core; Not provided; Scanner; Stratigraphy", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "McGwire, Kenneth C.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Digital Optical Imaging of Ice Cores for Curation and Scientific Applications", "uid": "p0000735", "west": null}, {"awards": "0125610 Waddington, Edwin", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 30 Apr 2007 00:00:00 GMT", "description": "0125610\u003cbr/\u003eWaddington\u003cbr/\u003e\u003cbr/\u003eThis award provides three years of funding to study the transition from slow inland flow to fast ice stream flow by making use of a suite of geophysical measurements that have been made near the onset region of ice stream D in West Antarctica. These data provide a unique opportunity to develop and validate glaciological models of the controlling processes in ice stream onset zones. Important processes to quantify are motion at the bed and deformation in the ice. Previous analyses indicate that the controlling resistive forces shift from the bed to the sides during the transition from slow inland flow to fast, streaming flow. Model sensitivity analyses will be used to investigate the relative importance of feedbacks between basal processes and ice deformation in the transition from inland to ice stream flow. Model experiments will determine what factors control the location of the onset of streaming flow, and how that location might migrate when conditions at the bed, or along the flow direction, changes over time. The overall goal of this work is to improve understanding of the evolution of the WAIS drainage system. This study is a first step towards understanding the physics that govern the transition from slow inland flow to fast streaming flow.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": false, "keywords": "FIXED OBSERVATION STATIONS", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Price, Stephen", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e FIXED OBSERVATION STATIONS", "repositories": null, "science_programs": null, "south": null, "title": "Model Investigations of the Transition from Inland to Ice Stream Flow", "uid": "p0000759", "west": null}, {"awards": "0229573 Mayewski, Paul", "bounds_geometry": null, "dataset_titles": "Antarctic Mean Annual Temperature Map", "datasets": [{"dataset_uid": "609318", "doi": "10.7265/N51C1TTV", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Temperature", "people": "Dixon, Daniel A.", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Mean Annual Temperature Map", "url": "https://www.usap-dc.org/view/dataset/609318"}], "date_created": "Wed, 04 Apr 2007 00:00:00 GMT", "description": "This award supports a science management office for a pilot ice-core drilling and analysis program to test the feasibility of obtaining well-dated, high-resolution isotope and chemistry records from East Antarctica. Shallow ice cores will be obtained from two locations: 1) ~100 km from South Pole towards the Pole of Inaccessibility, as an extension of the Byrd Station-to-South Pole ITASE traverse [International Trans Antarctic Scientific Expedition]; 2) at Taylor Dome, near the original deep coring site, and (3) possibly at AGO 3 and AGO 4 as part of a logistics traverse to these sites. All of the cores collected will be sampled at very high resolution (~1/2 cm) and analyzed for major ions. Results from this calibration work, along with those from another project that is analyzing stable isotopes will be used to help plan a program of larger scope, with the objective of mapping the spatial expression of climate variability in East Antarctica. Funds are also provided to organize a community workshop for coordination of the second phase of US ITASE and for one workshop per year for two years dedicated to writing and preparation of scientific papers from phase one of US ITASE. In addition, route selection activities for the follow-on traverse activities in East Antarctica will be conducted using satellite image mapping. A summary document will be produced and made available to the community to help with planning of related field programs (e.g. deep ice radar, firn radar profiling, atmospheric chemistry, ice coring, snow surface properties for satellite observations, ice surface elevation and mass balance).", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMOCOUPLES \u003e THERMOCOUPLES; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMOMETERS \u003e THERMOMETERS", "is_usap_dc": true, "keywords": "Antarctic Ice Sheet; West Antarctica; FIELD INVESTIGATION; West Antarctic Ice Sheet; Antarctic; Temperature; East Antarctic Plateau; FIELD SURVEYS; Antarctica; Not provided", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet; West Antarctica; West Antarctic Ice Sheet; East Antarctic Plateau", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Dixon, Daniel A.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "A Science Management Office for the U. S. Component of the International Trans Antarctic Expedition (US ITASE SMO)A Collaborative Pgrm of Research from S. Pole to N. Victoria Land", "uid": "p0000199", "west": null}, {"awards": "0408475 Harry, Dennis", "bounds_geometry": "POINT(-175 -85)", "dataset_titles": null, "datasets": null, "date_created": "Tue, 06 Mar 2007 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to apply numerical modeling to constrain the uplift and exhumation history of the Transantarctic Mountains. The Transantarctic Mountains (TAM) are an anomalously high (\u003e4500 m) and relatively broad (up to 200 km) rift-flank uplift demarcating the boundary between East and West Antarctica. Dynamics of the East Antarctic ice-sheet and the climate are affected by the mountain range, and an understanding of the uplift history of the mountain range is critical to understanding these processes. This project will constrain the uplift and denudation history of the Transantarctic Mountains based on thermo-mechanical modeling held faithful to thermochronological, geological, and geophysical data. The research will be the primary responsibility of post-doctoral researcher Audrey Huerta, working in collaboration with Dennis Harry, 1 undergraduate student, and 1 graduate student.\u003cbr/\u003e\u003cbr/\u003eThermochronologic evidence of episodic Cretaceous through Cenozoic rapid cooling within the TAM indicates distinct periods of uplift and exhumation. However, a more detailed interpretation of the uplift history is difficult without an understanding of the evolving thermal structure and topography of the TAM prior to and during uplift. These aspects of the mountain range can best be constrained by an understanding of the evolving regional tectonic setting. Proximity of the TAM to the West Antarctic Rift System (WARS) suggests a link between uplift of the TAM and extension within the WARS.\u003cbr/\u003e\u003cbr/\u003eThe project will integrate two techniques: lithospheric-scale geodynamic modeling and crustal-scale thermal modeling. The lithospheric-scale deformational and thermal evolution of TAM will be modeled by a finite element model designed to track the thermal and deformational response of the Antarctic lithosphere to a protracted extensional environment. Previous investigators have linked the high elevation and broad width of the TAM to a deep level of necking in which mantle thinning is offset from the location of crustal extension. In this study, a three-dimensional dynamic model will be used to track the uplift and thermal evolution of the TAM in a setting in which necking is at a deep level, and in which extension within the crust and extension within the mantle are offset. Velocity boundary conditions applied to the edges of the model will vary through time to simulate the extensional and transtensional evolution of the WARS. Because the model is dynamic, the thermal structure, strength, and strain field, evolve naturally in response to these initial and boundary conditions.\u003cbr/\u003e\u003cbr/\u003eDynamic models are uniquely suited to understanding lithospheric deformational and thermal evolution, however kinematic models are best suited for addressing the detailed thermal and exhumation history of crustal uplifts. Thus, a 2-dimensional kinematic-thermal model will be designed to simulate the uplift history of the TAM and the resulting erosional, topographic, and thermal evolution. Uplift will be modeled as normal-fault movement on a set of discrete fault planes with uplift rate varying through time. Erosion will be modeled as a diffusive process in which erosion rates can be varied through time (simulating climate changes), and vary spatially as a linear function of gradient and distance from the drainage divide. Synthetic time-temperature (t-T) histories will be calculated to compare model results to thermochronologic data.", "east": -175.0, "geometry": "POINT(-175 -85)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -85.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC; PHANEROZOIC \u003e MESOZOIC \u003e CRETACEOUS; PHANEROZOIC \u003e CENOZOIC \u003e PALEOGENE", "persons": "Huerta, Audrey D.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -85.0, "title": "Uplift and Exhumation of the Transantarctic Mountains and Relation to Rifting in West Antarctica", "uid": "p0000728", "west": -175.0}, {"awards": "9814816 Blankenship, Donald", "bounds_geometry": "POLYGON((-129 -80.5,-128.4 -80.5,-127.8 -80.5,-127.2 -80.5,-126.6 -80.5,-126 -80.5,-125.4 -80.5,-124.8 -80.5,-124.2 -80.5,-123.6 -80.5,-123 -80.5,-123 -80.55,-123 -80.6,-123 -80.65,-123 -80.7,-123 -80.75,-123 -80.8,-123 -80.85,-123 -80.9,-123 -80.95,-123 -81,-123.6 -81,-124.2 -81,-124.8 -81,-125.4 -81,-126 -81,-126.6 -81,-127.2 -81,-127.8 -81,-128.4 -81,-129 -81,-129 -80.95,-129 -80.9,-129 -80.85,-129 -80.8,-129 -80.75,-129 -80.7,-129 -80.65,-129 -80.6,-129 -80.55,-129 -80.5))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 13 Feb 2007 00:00:00 GMT", "description": "9814816 Blankenship This award supports a four year project to develop of better understanding the ice streams of the Ross Sea Embayment (A--F) which drain the interior West Antarctic Ice Sheet (WAIS) by rapidly moving vast quantities of ice to the calving front of the Ross Ice Shelf. The project will examine the role of these ice streams as buffers between the interior ice and the floating ice shelves. The reasons for their fast flow, the factors controlling their current grounding-line-, margin-, and head-positions are crucial to any attempt at modeling the WAIS system and predicting the future of the ice sheet. For the Antarctic ice streams of the Siple Coast, the transition from no-sliding (or all internal deformation) to motion dominated by sliding is defined as the \"onset-region\". To fully understand (and adequately model) the WAIS, this onset region must be better understood. The lateral margins of the ice streams are also a transition that need better explanation. Hypotheses on controls of the location of the onset region range from the \"purely-glaciologic\" to the \"purely-geologic. Thus, to model the ice sheet accurately, the basal boundary conditions (roughness, wetness, till properties) and a good subglacial geologic map, showing the distribution, thickness, and properties of the sedimentary basins, are required. These parameters can be estimated from seismic, radar, and other geophysical methods. The transition region of ice stream D will be studied in detail with this coupled geophysical experiment. In addition, selected other locations on ice streams C \u0026 D will be made, to compare and contrast conditions with the main site on ice stream D. Site-selection for the main camp will be based on existing radar, GPS, and satellite data as well as input from the modeling community.", "east": -123.0, "geometry": "POINT(-126 -80.75)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -80.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Blankenship, Donald D.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -81.0, "title": "Collaborative Research: Characterizing the Onset of Ice Stream Flow: A Ground Geophysical Field Program", "uid": "p0000603", "west": -129.0}, {"awards": "0126270 Doran, Peter", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 05 Feb 2007 00:00:00 GMT", "description": "Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Doran, Peter", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Paleoclimate Inferred from Lake Sediment Cores in Taylor Valley, Antarctica", "uid": "p0000092", "west": null}, {"awards": "0229917 Becker, Luann", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 24 Jan 2007 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an interdisciplinary study of fluvial sediments in Antarctica for evidence of what caused the greatest of all mass extinctions in the history of life at the Permian-Triassic boundary. This boundary was, until recently, difficult to locate and thought to be unequivocally disconformable in Antarctica. New studies, particularly of carbon isotopic chemostratigraphy and of paleosols and root traces as paleoecosystem indicators, together with improved fossil plant, reptile and pollen biostratigraphy, now suggest that the precise location of the boundary might be identified and have led to local discovery of iridium anomalies, shocked quartz, and fullerenes with extraterrestrial noble gases. These anomalies are associated with a distinctive claystone breccia bed, similar to strata known in South Africa and Australia, and taken as evidence of deforestation. There is already much evidence from Antarctica and elsewhere that the mass extinction on land was abrupt and synchronous with extinction in the ocean. The problem now is what led to such death and destruction. Carbon isotopic values are so low in these and other Permian-Triassic boundary sections that there was likely to have been some role for catastrophic destabilization of methane clathrates. Getting the modeled amount of methane out of likely reservoirs would require such catastrophic events as bolide impact, flood-basalt eruption or continental-shelf collapse, which have all independently been implicated in the mass extinction and for which there is independent evidence. Teasing apart these various hypotheses requires careful re-examination of beds that appear to represent the Permian-Triassic boundary, and search for more informative sequences, as was the case for the Cretaceous-Tertiary boundary. This collaborative research on geochemistry and petrography of boundary beds and paleosols (by Retallack), on carbon isotopic variation through the boundary interval (by Jahren), and on fullerenes, iridium and helium (by Becker) is designed to test these ideas about the Permian-Triassic boundary in Antarctica and to shed light on processes which contributed to this largest of mass extinctions on Earth. Fieldwork for this research will be conducted in the central Transantarctic Mountains and in Southern Victoria Land with an initial objective of examining the stratigraphic sequences for continuity across the boundary. Stratigraphic continuity is a critical element that must exist for the work to be successful. If fieldwork indicates sufficiently continuous sections, the full analytical program will follow fieldwork.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e PROBES; SOLAR/SPACE OBSERVING INSTRUMENTS \u003e PARTICLE DETECTORS \u003e SEM", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Becker, Luann", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Permian-Triassic Mass Extinction in Antarctica", "uid": "p0000718", "west": null}, {"awards": "0229245 Hamilton, Gordon", "bounds_geometry": "POINT(135 -76)", "dataset_titles": null, "datasets": null, "date_created": "Thu, 30 Mar 2006 00:00:00 GMT", "description": "A \u0027horizontal ice core\u0027 was collected at the Mount Moulton blue ice field in West Antarctica and preliminary analyses of the sample material suggests that a ~500 kyr climate record is preserved in the ice at this site. This award will contribute to the understanding of the Mt Moulton record by assessing the potential for ice-flow induced deformation of the stratigraphic profile. In addition, this award builds on the recognition of blue ice areas as archives of long climate records by conducting reconnaissance studies for a potential horizontal ice core location at the Allan Hills in East Antarctica. The objectives of this project are to contribute to the glaciological understanding of blue ice areas in Antarctica. Ice flow conditions at the Mt Moulton blue ice field will be studied to assess the possibility that the stratigraphic record has been deformed and reconnaissance of a potential horizontal ice core site in the Allan Hills blue ice field will also be accomplished. Short field programs will be undertaken at each location to collect relevant measurements of ice flow and subglacial topography, and to conduct sampling of material that will enable the preservation of the stratigraphic sequences to be assessed.", "east": 135.0, "geometry": "POINT(135 -76)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e ACOUSTIC RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR", "is_usap_dc": false, "keywords": "Mount Moulton; Not provided; Subglacial Topography; FIELD INVESTIGATION; Ice Flow; West Antarctica; FIELD SURVEYS; Stratigraphy; Horizontal Ice Core; GROUND-BASED OBSERVATIONS; Blue Ice; Radar", "locations": "Mount Moulton; West Antarctica", "north": -76.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bauer, Rob; Hamilton, Gordon S.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided", "repositories": null, "science_programs": null, "south": -76.0, "title": "Glaciology of Blue Ice Areas in Antarctica", "uid": "p0000248", "west": 135.0}, {"awards": "9814574 Jacobel, Robert", "bounds_geometry": "POLYGON((-120 -80,-115.6 -80,-111.2 -80,-106.8 -80,-102.4 -80,-98 -80,-93.6 -80,-89.2 -80,-84.8 -80,-80.4 -80,-76 -80,-76 -81,-76 -82,-76 -83,-76 -84,-76 -85,-76 -86,-76 -87,-76 -88,-76 -89,-76 -90,-80.4 -90,-84.8 -90,-89.2 -90,-93.6 -90,-98 -90,-102.4 -90,-106.8 -90,-111.2 -90,-115.6 -90,-120 -90,-120 -89,-120 -88,-120 -87,-120 -86,-120 -85,-120 -84,-120 -83,-120 -82,-120 -81,-120 -80))", "dataset_titles": "Ice Thickness and Internal Layer Depth Along the 2001 and 2002 US ITASE Traverses", "datasets": [{"dataset_uid": "609264", "doi": "10.7265/N5R20Z9T", "keywords": "Airborne Radar; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; ITASE; WAIS", "people": "Welch, Brian; Jacobel, Robert", "repository": "USAP-DC", "science_program": "ITASE", "title": "Ice Thickness and Internal Layer Depth Along the 2001 and 2002 US ITASE Traverses", "url": "https://www.usap-dc.org/view/dataset/609264"}], "date_created": "Fri, 08 Apr 2005 00:00:00 GMT", "description": "This award supports a program of radar studies of internal stratigraphy and bedrock topography along the traverses for the U.S. component of the International Trans-Antarctic Scientific Expedition (US ITASE). The radar will provide information immediately available in the field on ice thickness and internal layer structure to help in the selection of core sites as the traverse proceeds. These data will also be useful in siting deeper millennial scale cores planned at less frequent intervals along the traverse, and in the selection of the location for the deep inland core planned for the future. In addition to continuous coverage along the traverse route, more detailed studies on a grid surrounding each of the core locations will be made to better characterize accumulation and bedrock topography in each area. This proposal is complimentary to the one submitted by the Cold Regions Research and Engineering Laboratory (CRREL), which proposes a high frequency radar to examine the shallower portion of the record down to approximately 60 meters, including the presence of near-surface crevasses. The radar proposed herein is most sensitive at depths below 60 meters and can depict deep bedrock and internal layers to a substantial fraction of the ice thickness.", "east": -76.0, "geometry": "POINT(-98 -85)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS", "is_usap_dc": true, "keywords": "US ITASE; Traverses; West Antarctica; Radar Echo Sounder; GROUND-BASED OBSERVATIONS; Radar Echo Sounding; Antarctica; Depth; Ice Thickness; Radar", "locations": "Antarctica; West Antarctica", "north": -80.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Jacobel, Robert; Welch, Brian", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ITASE", "south": -90.0, "title": "Radar Studies of Internal Stratigraphy and Bedrock Topography along the US ITASE Traverse", "uid": "p0000595", "west": -120.0}, {"awards": "9316564 Mayewski, Paul", "bounds_geometry": null, "dataset_titles": "Ross Ice Drainage System (RIDS) Glaciochemical Analysis; Siple Dome Ice Core Chemistry and Ion Data", "datasets": [{"dataset_uid": "609266", "doi": "10.7265/N5M906KG", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Snow/ice; Snow/Ice; Snow Pit", "people": "Kreutz, Karl; Mayewski, Paul A.; Twickler, Mark; Whitlow, Sallie; Meeker, Loren D.", "repository": "USAP-DC", "science_program": null, "title": "Ross Ice Drainage System (RIDS) Glaciochemical Analysis", "url": "https://www.usap-dc.org/view/dataset/609266"}, {"dataset_uid": "609251", "doi": "", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Severinghaus, Jeffrey P.; Dunbar, Nelia; Mayewski, Paul A.; Kreutz, Karl; Brook, Edward J.; Blunier, Thomas", "repository": "NCEI", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Ice Core Chemistry and Ion Data", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/2461"}], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": "9316564 Mayewski This award is for support for a three year program to provide a high resolution record of the Antarctic climate through the acquisition, analysis, and interpretation of records of atmospheric chemical deposition taken from three ice cores located at sites within or immediately adjacent to the Ross Ice Drainage System (RIDS). These cores include one from Taylor Dome, and two from West Antarctic locations identified as potential deep drilling sites for the WAISCORES program. Collection of the two West Antarctic cores is intended to be a lightweight dry-drilling operation to depths of ~ 200 m, which will provide records of \u003e 2 kyr. Glaciochemical analyses will focus on the major cations and anions found in the antarctic atmosphere, plus methanesulfonic acid and selected measurements of the hydrogen ion, aluminum, iron, and silica. These analyses, and companion stable isotope and particle measurements to be carried out by other investigators require \u003c 7% by volume of each core, leaving \u003e 90% for other investigators and storage at the U.S. National Ice Core Laboratory. These records are intended to solve a variety of scientific objectives while also providing spatial sampling and reconnaissance for future U.S. efforts in West Antarctica. ***", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Magnesium; GROUND STATIONS; Nitrate; Methane Sulfonic Acid; Sodium; Ice Core Chemistry; Ammonium (NH4); Sulfate; Ice Core; Chloride; Potassium (k); Calcium (ca)", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kreutz, Karl; Twickler, Mark; Whitlow, Sallie; Blunier, Thomas; Dunbar, Nelia; Brook, Edward J.; Mayewski, Paul A.; Meeker, Loren D.; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "NCEI; USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Ross Ice Drainage System (RIDS) Late Holocene Climate Variability", "uid": "p0000145", "west": null}, {"awards": "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}]
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Ecosystems worldwide are threatened by anthropogenic changes in climate. Lakes are widely regarded as sentinels of climate change and, among these, polar lakes are the most sensitive. Beneath meters of permanent ice and liquid water, many Antarctic lakes contain complex microbial communities that are already being transformed by climate change. The structurally complex spatial patterns that these microbes create provide the opportunity to pursue research questions about spatial ecology that cannot be addressed elsewhere. This project focuses on research that will advance understanding of the spatial structure of benthic communities in Antarctic lakes, their relationships with environmental conditions, and predictions for likely changes in the future. This project will also advance methods in integrating the morphology and spatial patterning of modern microbial communities in relationship to their biophysical and biochemical environments. The quantitative framework being developed has potential to refine understanding of controls on microbial community patterning and thus interpretation of both the effects of climate change and ancient fossil microbial communities in the geologic record. Such understanding will address key questions about Earth’s evolutionary and environmental history and future. Lake Vanda in the McMurdo Dry Valleys, Antarctic, has modern microbial pinnacles covering its lake floor. Using existing datasets on spatial structure of benthic communities from 37 sites on the floor of Lake Vanda, the project team will apply recent theories from Spatial Ecology to investigate the mechanisms that give rise to spatial patterns of pinnacles formed by benthic microbes. The work addresses two questions: (1) What are the morphological and spatial patterns of pinnacles and how do they vary over developmental stages, along environment gradients, and from 2013 to 2023? And (2) what mechanisms give rise to the geometry of individual pinnacles and their spatial distribution? Lake Vanda provides an exceptional opportunity to address these questions. It features well characterized gradients in sedimentation, nutrients, irradiance, transport mechanism, and colonization history. Benthic communities at different locations in the lake manifest distinct spatial patterns, as they experience distinct conditions. Lake level has increased >10 m in the past few decades, creating additional opportunities for a “natural experiment” on pattern development by comparing relatively newly flooded substrates (pinnacles of 1 to 15 years old) with deeper, well-developed mats (> 70 years old). Since microbial communities respond to environmental change rapidly, analyses can characterize changes in patterns in pinnacle spatial data collected 9 years apart (Dec 2013 and Jan 2023), providing the opportunity to directly assess responses of spatially self-organized ecosystems to environmental change. As such, Lake Vanda is a natural laboratory that allows research (1) to effectively sort out mechanisms of pattern formation affecting benthic microbial communities residing there; and (2) to test the theory of spatial self-organization: mechanisms of pattern formation and responses to perturbations, applicable to ecosystems worldwide. Research questions will be addressed by integrating existing datasets, spatial pattern analyses, Bayesian statistical models, and process-based numerical models. 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.
One of the fundamental processes in plate tectonics is the rifting or separating of continental crust creating new seafloors which can widen and ultimately form new ocean basins, the latter is a process known as seafloor spreading. The Bransfield Strait, separating the West Antarctic Peninsula from the South Shetland Islands, formed and is presently widening as a result of the separation of continental crust. What is unique is that the system appears to be approaching the transition to seafloor spreading making this an ideal site to study the transitional process. Previous seafloor mapping and field surveys provide the regional structure of the basin; however, there exists a paucity of regional seismic studies documenting the tectonic and volcanic activity in the basin as a result of the rifting. This would be the first local-scale study of the seismicity and structure of the volcanoes in the center of the basin where crustal separation is most active. The new seismic data will enable scientists to compare current patterns of crustal separation and volcanism at the Bransfield Strait to other well-studied seafloor spreading centers. This collaborative international project, led by the Spanish and involving scientists from the U.S., Germany and other European countries, will monitor seismicity for one year on land and on the seafloor. An active seismic study conducted by the Spanish will image fault and volcanic structures that can be related to the distribution of earthquakes. Back-arc basins are found in subduction settings and form in two stages, an initial interval of continental rifting that transitions to a later stage of seafloor spreading. Studying the transitional process is important for understanding the dynamics and evolution of subduction zones, and in locations where back-arc rifting breaks continental crust, it is relevant to understanding the formation of passive continental margins. The Central Bransfield Basin is unusual in that the South Shetland Islands have lacked recent arc volcanism and it appears subduction is ceasing, but this system has broad significant because it appears to be nearing the transition from rifting to seafloor spreading. This award will support the U.S. component of an international initiative led by the Spanish Polar Committee to conduct a study of the seismicity and volcanic structure of the Central Bransfield Basin. The objective is to characterize the distribution of active extension across the basin and determine whether the volcanic structure and deformation of the rift are consistent with a back-arc basin that is transitioning from rifting to seafloor spreading. The U.S. component of the experiment will contribute a network of six hydroacoustic moorings to monitor regional seismicity and 15 short-period seismometers to study the distribution of tectonic and volcanic seismicity on Orca volcano, one of the most active volcanoes in the basin. An active seismic study across closely spaced multichannel seismic lines across the rift will provide the data necessary to link earthquakes with fault structures enabling a tomography study of Orca volcano and provide insight into how the volcano's structure relates to rifting. This research will constrain the distribution of active rifting across the Central Bransfield Basin and determine whether the patterns of faulting and the structure of volcanic portion of the rift are consistent with a diffuse zone of rifting or a single spreading center that is transitioning to the production of oceanic crust. The Bransfield Basin is an ideal site for a comparative study of seismic and hydroacoustic earthquake locations that will improve the understanding of the generation and propagation of T-wave signals and contribute to efforts to compare the result of T-wave studies with data from traditional solid-earth seismic studies. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This workshop will bring together Antarctic marine freshwater and terrestrial biologists, students, and experts in specimen curation to assess the value of, need for, and scope of a biological repository of Antarctic specimens, including tissue samples. Currently, some US collected Antarctic specimen collections are housed in various museums, repositories, and labs. These collections are not easily discoverable on the internet, and how well they represent the biodiversity of Antarctica is largely unknown. The workshop coordinators will advertise the conference broadly and recruit underrepresented groups to participate. Participants will assess current repositories and determine how to make Antarctica biological samples more accessible in a unified location (or through better coordination). This effort will benefit the broader community of biologists working with Antarctic organisms by providing opportunities to conduct Antarctic science by investigators and their students that might otherwise not be possible due to the logistical and budget challenges for deployments. Following workshop activities, a final report will be published on the outcomes of the efforts. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part I: Non-technical description: The crabeater seal is the most important predator of Antarctic krill in the western Antarctic Peninsula oceanic waters after the disappearance of large whales due to human hunting 100 years ago. The crabeater seals are expected to consume large quantities of krill due to their high abundance (about 7 million individuals), large body size (about 700 pounds in body weight), high metabolism and a diet specializing in krill. This species depends on sea ice presence all year long, living, reproducing, and diving to feed from that environment, making this marine mammal species a good indicator, or sentinel, of how the Antarctic ecosystem responds to a changing climate. As sea ice has been decreasing in the northern Antarctic Peninsula, this project aims to understand if the species food availability has changed in the last decades in response to environmental changes. In particular, the proposed work will concentrate on known populations of crabeater seals in northern (i.e., warmer, sub-polar) and southern (i.e., colder, polar) Antarctic Peninsula, 450 miles apart, making measurements on the abundance, physiology, metabolic needs and movement of the crabeater populations in both locations. The data will be combined to build models that will quantify the existing differences between northern and southern populations, as well as predict their future change, and compare present-day measurements with those collected by the British Antarctic Survey in the mid-1900s. The project is a collaboration between an international and interdisciplinary team from the United States and United Kingdom, benefitting NSF goals to facilitate collaborative geoscience research projects involving these two countries as well as aligning directly with U.S. Global Change Research Program (USGCRP) to better understand the forces shaping the global environment, both human and natural, and their impacts on society. To further increase polar literacy and education, Principal Investigators will train at least 2 graduate students and several undergraduates across two US institutions, as well as one UK-based post-doctoral researcher. Part II: Technical description: Crabeater seals (Lobodon carcinophaga) are considered an excellent sentinel species through which to examine the effects of a changing climate on the extended Antarctic krill-dependent predator community and the structure of the entire ecosystem of the western Antarctic Peninsula. Over the last forty years, there have been significant changes in the temporal and spatial patterns of primary productivity, and shifts in the population dynamics of Antarctic krill, the dominant mid-trophic level species. The impact of such changes on year-round resident species of crabeater seals (the most important predator of Antarctic krill) is more difficult to understand as they are not associated with breeding colonies where their population fluctuations could be more readily observed. The proposed research is conceived under the premise that environmental change has accentuated the differences between the northern and southern western Antarctic Peninsula crabeater seal populations due to differential reductions in sea-ice and its possible effect on prey availability. To address this question, this research will combine measurements on animal movement, stable isotope analyses, whole-animal physiology, and novel survey technologies (small Unmanned Aircraft Systems, satellite imagery) to build models. The project is a collaboration between an international and interdisciplinary team from the United States and United Kingdom. These studies will be essential to detect past, and project future, changes in the ecology of this species in response to changes in sea ice when comparing present-day measurements with those collected by the British Antarctic Survey in the mid-1900s. To further increase polar literacy and education, Principal Investigators will train at least 2 graduate students and several undergraduates across two US institutions, as well as one UK-based post-doctoral researcher. Students involved with this project will gain invaluable research experience in the lab and will have a unique opportunity to participate in Antarctic fieldwork. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Gentoo penguins (Pygoscelis papua) inhabit one of the fastest warming regions on Earth, the Western Antarctic Peninsula (WAP), where environmental shifts are measured in years, not decades. Despite this, the species is flourishing, growing in numbers and colonizing new habitats while sister species, such as Adélie penguins (P. adeliae), are declining in the region. This project will investigate to what extent epigenetics contributes to the success of gentoo penguins. Epigenetic variation is controlled by modifications to DNA or chromatin structure that affect the expression of genes, rather than changes to the underlying DNA sequence. This project will improve the understanding of gentoo penguin adaptation to climate change, and whether it is a result of increased flexibility in behavior and physiology driven by a greater capacity for epigenetic changes (i.e., epigenetic potential). The most studied form of epigenetic variation is the profiling of DNA methylation patterns. Environmental effects can trigger changes in DNA methylation that target specific tissues, allowing for localized gene expression shifts that result in modifications to the phenotype of an organism without any alteration to the underlying genotype. Given that epigenetic variation between populations often exceeds genetic variation, fine-scale genetic differentiation observed amongst gentoo penguin colonies suggests the possibility for local adaptation via even more divergent epigenetic changes and provides a framework for examining epigenetic variation across the gentoo penguin breeding range along multiple ecological axes. The researchers will test this by comprehensively characterizing the epigenomic profiles via patterns of DNA methylation in wild gentoo and Adélie penguins using cutting-edge high-resolution genomics techniques. Specifically, they will investigate whether gentoo penguins exhibit a greater degree of differences in DNA-methylation than underlying genetic differences, suggesting such epigenetic variation is driven by external environmental variables, potentially leading to improved capacity for local adaptation. This project will explore whether epigenetic potential may be selected for in individuals who disperse to new colony locations by comparing older, established colonies to new colonies at the range-edge. By implementing cutting-edge epigenetic methods in wild populations of gentoo penguins, this project will help address ecological questions on environmental plasticity that will impact conservation efforts and decisions on Marine Protected Areas (MPAs) on the Antarctic Peninsula. 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.
Geodiversity is the variety of non-living elements like rocks, landforms, and processes in a given area, and plays an especially critical role in Antarctica. Geodiversity provides the conditions in which life can develop and underpins all ecosystems on Earth. It also provides tangible services to people (like construction materials) as well as intangible benefits (such as scientific knowledge from ice cores and artistic inspiration from glaciers). Despite its importance, Antarctic geodiversity remains under-explored, under-described, and inadequately mapped. This knowledge gap is particularly concerning given the threats posed by increasing human activity and environmental and climate change. This project uses a variety of datasets to map Antarctic geodiversity, assess its benefits to people, and help identify priority locations for conservation. Through an interdisciplinary and mixed-method approach, this research will fill a major gap in the current understanding and representations of the Antarctic. Using the McMurdo Dry Valleys as a case study, the researcher will combine geospatial data on geology, geomorphology, pedology, and hydrology to map geodiversity of the region. This project will identify sites of key geosystem services by analyzing geospatial data on placenames, scientific samples, and a web-based participatory mapping survey. The geodiversity and geosystem services data will then be overlaid and combined to identify hotspots of geo-social diversity. The resulting maps will be compared with the region's protected area boundaries to assess the fit-for-purpose of current environmental management and identify priority locations for future research and conservation. The fellow will promote Antarctic geodiversity broadly, including at UNESCO International Geodiversity Day. 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.
Marine ice sheets are low-pass filters of climate variability that take centuries to adjust to interior and near-terminus changes in mass balance. Constraining these century-scale changes from satellite observations that span only the last 40 years is challenging. Here, we take a different approach of carefully synthesizing different data sets to infer changes in the configurations of van der Veen and Mercer Ice Streams on the Siple Coast over the past 3000 years from englacial features encoded in ice-penetrating radar data. Englacial radar data from Conway Ridge reveal smooth, surface conformal layers overlying disrupted stratigraphy that suggest the van der Veen Ice Stream was 40 km wider over 3000 years ago. Englacial layer dating indicates that the ice stream narrowed to its present configuration between $\sim3000$ and $\sim1000$ years ago. Similarly disrupted stratigraphy and buried crevasses suggest that ice flowing from Mercer to Whillans Ice Stream across the northwestern tip of the ridge slowed shortly after. Using an ice-flow model capable of simulating shear margin migration, we evaluate whether small changes in ice thickness can lead to large changes in shear margin location. Our results suggest that the tip of Conway Ridge is sensitive to thinning and thickening, and that when the basal strength at the tip of the ridge increases with the height above flotation, the ice sheet shear margins can change quickly.
Ice penetrating radar is one of the primary tools that researchers use to study ice sheets and glaciers. With radar, it is possible to see a cross-section of the ice, revealing internal layers and the shape of the rocks under the ice. Among other things, this is important for calculating how much potential sea level change is locked up in the polar ice sheets, and how stable the ice sheets are likely to be in a warming world. This type of data is logistically challenging and expensive to collect. Historically, individual research groups have obtained funding to collect these data sets, and then the data largely stayed within that institution. There has been a recent push to make more and more data openly available, enabling the same datasets to be used by multiple research groups. However, it is still difficult to figure out what data is available because there is no centralized index. Additionally, each group releases data in a different format, which creates an additional hurdle to its use. This project addresses both of those challenges to data reuse by providing a unified tool for discovering where ice penetrating radar data already exists, then allowing the researcher to download and visualize the data. It is integrated into open-source mapping software that many in the research community already use, and makes it possible for non-experts to explore these datasets. This is particularly valuable for early-career researchers and for enabling interdisciplinary work. The US alone has spent many tens of millions of dollars on direct grants to enable the acquisition and analysis of polar ice penetrating radar data, and even more on the associated infrastructure and support costs. Unfortunately, much of these data is not publicly released, and even the data that has been released is not easily accessible. There is significant technical work involved in figuring out how to locate, download and view the data. This project is developing a tool that will both lower the barrier to entry for using this data and improve the workflows of existing users. Quantarctica and QGreenland have rapidly become indispensable tools for the polar research community, making diverse data sets readily available to researchers. However, ice penetrating radar is a major category of data that is not currently supported – it is possible to see the locations of existing survey lines, and the ice thickness maps that have been interpreted from their data, but it is not readily possible to see the radargrams themselves in context with all of the other information. This capability is important because there is far more visual information contained in a radargram than simply its interpreted basal elevation or ice thickness. This project is developing software that will enable researchers to to view radargram images and interpreted surface and basal horizons in context with the existing map-view datasets in Quantarctica and QGreenland. A data layer shows the locations of all known ice penetrating radar surveys, color-coded based on availability. This layer enables data discovery and browsing. The plugin itself interacts with the data layer, first to download selected data, then to visualize the radargrams along with a cursor that moves simultaneously along the radargram and along the map view, making it straightforward to determine the precise geolocation of radar features. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Phytoplankton are microscopic single-celled plants that grow at the sun-lit surface of the ocean. In the Southern Ocean around Antarctica, phytoplankton live in sub-optimal conditions because the amount of iron in seawater is insufficient for growth. Moreover, the chemical composition of Southern Ocean phytoplankton is distinct from that in other ocean regions, with a higher proportion of phosphorus relative to other elements, a characteristic that ultimately influences the distribution of nutrients ocean-wide. The researchers hypothesize that the high phosphorus composition of phytoplankton in the Southern Ocean is caused by their low iron content. Specifically, they postulate that a phosphorus-rich molecule, phytic acid, is synthesized by phytoplankton in order to assist in the storage of iron in designated cellular compartments, such as vacuoles. Recent observations show that some phytoplankton can absorb phytic acid, suggesting that it may be produced by certain species. Phytic acid is pervasive in soils, wherein it aids absorption of iron via plant roots and could similarly help phytoplankton in the Southern Ocean acquire iron via the cell membranes. This project benefits the National Science Foundation's goals of improving understanding of interactions between the Southern Ocean and the global ocean, of expanding fundamental knowledge of Antarctic biota and associated processes by focusing on phytoplankton species unique to the Antarctic. As part of this project, the Department of Marine Sciences from the College of Liberal Arts and Sciences at the University of Connecticut will sponsor the recruitment, relocation and mentorship of a graduate student under-represented in the sciences. This project aims to determine whether the unusual elemental composition of phytoplankton at the Southern Ocean is a result of anemia. The work will query whether inositol hexakisphosphate (phytic acid) aids Antarctic phytoplankton acquire and store iron, resulting in an elevated fraction of cellular phosphorus relative to other elements. The researchers, including a graduate student, will conduct laboratory culture experiments with phytoplankton strains isolated from the Southern Ocean. They will grow cells in iron- deficient versus iron-replete media to see if their phosphorus content is higher in iron-deficient conditions. They will test whether cells grown with sufficient phosphorus acquire more iron, allowing them to grow better in iron-deficient conditions than cells deriving from phosphorus-poor conditions. They will also query whether cells grown in iron-deficient conditions achieve faster growth rates in the presence of phytic acid. Results will inform the design of CRISPR mutants with which to investigate phosphorus and iron co-metabolism in Antarctic marine phytoplankton. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part 1: Nontechnical Unlike other locations on the globe Antarctica is not known for having large earthquakes and the remote nature and harsh conditions make it difficult to install and maintain seismometers for earthquake detection. Some researchers believe the lack of large earthquakes is due to the continent being surrounded by inactive tectonic margins. However, in the last two decades, scientists have discovered that more earthquakes occur in the interior of the continent than previously observed. This suggests that there are many earthquakes missing from historic earthquake catalogs. This study aims to find the missing earthquakes using novel earthquake detection and location techniques from seismic data collected from temporary and permanent seismic stations in Antarctica over the last 25 years. Locating these earthquakes will help understand if and where earthquakes are located in Antarctica and will help in planning future seismic deployments. As part of the project broader impacts, a field expedition with the Girls on Rock program will be conducted to teach high school age girls, and especially those from underrepresented backgrounds, data visualization techniques using scientific data. Part 2: Technical The spatial distribution of seismicity and the number of moderate magnitude earthquakes in Antarctica is not well-defined. The current catalog of earthquakes may be biased by uneven and sparse seismograph distribution on the continent. We will mine existing broadband seismic data from both permanent and temporary deployments to lower the earthquake detection threshold across Interior Antarctica, with a focus on tectonic earthquakes. The hypothesis is that Interior Antarctica has abundant moderate magnitude earthquakes, previously undetected. These earthquakes are likely collocated with major tectonic features such as the Transantarctic Mountains, the suspected Vostok collision zone, the West Antarctic Rift System, the crustal compositional boundary between East and West Antarctica, and the Cretaceous East Antarctic Rift. Previous seismic deployments have recorded earthquakes in the Antarctic interior, suggesting there are many earthquakes missing from the current catalog. We propose to use novel earthquake location techniques designed for automated detection and location using 25 years of continuous data archived at IRIS from PASSCAL experiments and permanent stations. The approach will use STA/LTA detectors on the first arrival P-wave to 90 degrees distance, Reverse Time Imaging to locate events, and beamforming at dense arrays strategically located on cratons for enhanced detection and location. The combination of detection and location techniques used in this work has not been used on teleseismic body waves, although similar methods have worked well for surface wave studies. If successful the project would provide an excellent training dataset for future scrutiny of newly discovered Antarctic seismicity with machine learning approaches and/or new targeted data collection. We plan to collaborate with Girls on Rock, a local and international organization committed to building a culturally diverse community in science, art, and wilderness exploration, in a summer field expedition and integrating computer coding into post-field scientific projects. 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.
Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function.<br/> <br/> <br/>To understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Couradeau, Estelle; Maximova, Siela; Machado, Jose Luis
No dataset link provided
Páramos are high-altitude tundra ecosystems nested at the heart of the Andes mountains. These cold and humid environments are home to a multitude of plants, animals, and insects. Páramos are a critical water source for downstream urban centers, including Colombia's capital city, Bogota. Additionally, the Páramos soils contain substantial organic carbon reserves due to slow rates of organic matter decomposition. Beyond being a pool of carbon sequestered away from the atmosphere, this large reservoir of organic matter controls the soils’ hydraulic and fertility properties. The Páramos’ unique geographic location, at an elevation above 2,800 m above sea level, makes them highly vulnerable to the impacts of climate change. In fact, these ecosystems’ surface areas are projected to shrink by half within the next 50 years possibly causing loss of the essential services they provide. This project aims to characterize the microbial diversity in the Páramos soils in Colombia and investigate how climate change will affect microbes’ functions. The research is of high importance, considering that immediate and long-term changes in microbial metabolism could impact the ability of Páramos soils to store organic carbon and regulate downstream water flow. To study the cascading effect of climate change on Páramos ecosystems, this project will jumpstart collaborations among transdisciplinary experts that will integrate the research of below-ground microbial communities with above-ground vegetation functions. The project will also engage high school and undergraduate students that will work together to develop and deploy low-cost long-term soil monitoring data loggers in Chingaza National Natural Park, near the city of Bogota. This project will address the critical need to disentangle the effect of moisture and temperature on the fate of organic carbon in Páramos soils while building a transdisciplinary team capable of expanding the scope of the research to an ecosystem level. The project includes establishing controlled soil mesocosms that will allow to independently vary moisture and temperature levels. Additionally, functions of the soil microbiome will be investigated using metagenomics and amplicon sequencing, and probes will be deployed to initiate long-term monitoring of the soil response to climate change in situ. This project will culminate in the organization of an international Páramos symposium that will set up priorities for future systems research. The symposium will bring together scientists from diverse fields to discuss the linkages between above-ground and below-ground ecosystem functions and plan future collaborations in predicting Páramos-wide effects of climate change. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Satellite observations of Earth’s surface gravity and elevation changes indicate rapid melting of ice sheets in recent decades in northern Antarctica Peninsula and Amundsen Sea Embayment of West Antarctica. This rapid melting may lead to significant global sea level rise which is a major societal concern. Measurements from the Global Positioning System (GPS) show rapid land uplift in these regions as the ice sheets melt. When an ice sheet melts, the melt water flows to oceans, causing global sea level to rise. However, the sea level change at a given geographic location is also influenced by two other factors associated with the ice melting process: 1) the vertical motion of the land and 2) gravitational attraction. The vertical motion of the land is caused by the change of pressure force on the surface of the solid Earth. For example, the removal of ice mass reduces the pressure force on the land, leading to uplift of the land below the ice sheet, while the addition of water in oceans increases the pressure force on the seafloor, causing it to subside. The sea level always follows the equipotential surface of the gravity which changes as the mass on the Earth’s surface (e.g., the ice and water) or/and in its interiors (e.g., at the crust-mantle boundary) is redistributed. Additionally, the vertical motion of the land below an ice sheet has important effects on the evolution and stability of the ice sheet and may determine whether the ice sheet will rapidly collapse or gradually stabilize. The main goal of this project is to build an accurate and efficient computer model to study the displacement and deformation of the Antarctic crust and mantle in response to recent ice melting. The project will significantly improve existing and publicly available computer code, CitcomSVE. The horizontal and vertical components of the Earth’s surface displacement depends on mantle viscosity and elastic properties of the Earth. Although seismic imaging studies demonstrate that the Antarctica mantle is heterogeneous, most studies on the ice-melting induced deformation in Antarctica have assumed that mantle viscosity and elastic properties only vary with the depth due to computational limitations. In this project, the new computational method in CitcomSVE avoids such assumptions and makes it possible to include realistic 3-D mantle viscosity and elastic properties in computing the Antarctica crustal and mantle displacement. This project will interpret the GPS measurements of the surface displacements in northern Antarctica Peninsula and Amundsen Sea Embayment of West Antarctica and use the observations to place constraints on mantle viscosity and deformation mechanisms. The project will also seek to predict the future land displacement Antarctica, which will lead to a better understand of Antarctica ice sheets. Finally, the project has direct implications for the study of global sea level change and the dynamics of the Greenland ice sheet. Technical Description Glacial isostatic adjustment (GIA) is important for understanding not only fundamental science questions including mantle viscosity, mantle convection and lithospheric deformation but also societally important questions of global sea-level change, polar ice melting, climate change, and groundwater hydrology. Studies of rock deformation in laboratory experiments, post-seismic deformation, and mantle dynamics indicate that mantle viscosity is temperature- and stress-dependent. Although the effects of stress-dependent (i.e., non-Newtonian) viscosity and transient creep rheology on GIA process have been studied, observational evidence remains elusive. There has been significant ice mass loss in recent decades in northern Antarctica Peninsula (NAP) and Amundsen Sea Embayment (ASE) of West Antarctica. The ice mass loss has caused rapid bedrock uplift as measured by GPS techniques which require surprisingly small upper mantle viscosity of ~1018 Pas. The rapid uplifts may have important feedback effects on ongoing ice melting because of their influence on grounding line migration, and the inferred small viscosity may have implications for mantle rheology and deformation on decadal time scales. The main objective of the project is to test hypotheses that the GPS observations in NAP and ASE regions are controlled by 3-D non-Newtonian or/and transient creep viscosity by developing new GIA modeling capability based on finite element package CitcomSVE. The project will carry out the following three tasks: Task 1 is to build GIA models for the NAP and ASE regions to examine the effects of 3-D temperature-dependent mantle viscosity on the surface displacements and to test hypothesis that the 3-D mantle viscosity improves the fit to the GPS observations. Task 2 is to test the hypothesis that non-Newtonian or/and transient creep rheology controls GIA process on decadal time scales by computing GIA models and comparing model predictions with GPS observations for the NAP and ASE regions. Task 3 is to implement transient creep (i.e., Burgers model) rheology into finite element package CitcomSVE for modeling the GIA process on global and regional scales and to make the package publicly available to the scientific community. The project will develop the first numerical GIA model with Burgers transient rheology and use the models to examine the effects of 3-D temperature-dependent viscosity, non-Newtonian viscosity and transient rheology on GIA-induced surface displacements in Antarctica. The project will model the unique GPS observations of unusually large displacement rates in the NAP and ASE regions to place constraints on mantle rheology and to distinguish between 3-D temperature-dependent, non-Newtonian and transient mantle viscosity. The project will expand the capability of the publicly available software package CitcomSVE for modeling viscoelastic deformation and tidal deformation on global and regional scales. The project will advance our understanding in lithospheric deformation and mantle rheology on decadal time scales, which helps predict grounding line migration and understand ice sheet stability in West Antarctica. The project will strengthen the open science practice by improving the publicly available code CitcomSVE at github. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The seaward motion of ice sheets and glaciers is primarily controlled by basal sliding at the base of the ice sheet and internal viscous flow within the ice mass. The latter of these — viscous flow — is dependent on various factors, including temperature, stress, grain size, and the alignment of ice crystals during flow to produce a "crystal orientation fabric" (COF). Historically, ice flow has been modeled using an equation, termed “Glen’s law”, that describes ice-flow rate as a function of temperature and stress. Glen’s law was constrained under relatively high-stress conditions and is often attributed to the motion of crystal defects within ice grains. More recently, however, grain boundary sliding (GBS) has been invoked as the rate-controlling process under low-stress, “superplastic” conditions. The grain boundary sliding hypothesis is contentious because GBS is not thought to produce a COF, whereas geophysical measurements and polar ice cores demonstrate strong COFs in polar ice masses. However, very few COF measurements have been conducted on ice samples subjected to superplastic flow conditions in the laboratory. This project would measure the evolution of ice COF across the transition from superplastic to Glen-type creep. Results will be used to interrogate the role of superplastic GBS creep within polar ice masses, and thereby provide constraints on polar ice discharge models. Polycrystalline ice samples with grain sizes ranging from 5 µm to 1000 µm will be fabricated and deformed in a laboratory, using a 1-atm cryogenic axial-torsion apparatus. Experiments will be conducted at temperatures of -30°C to -10°C, and at a constant uniaxial strain rate. Under these conditions, 5% to 99.99% of strain should be accommodated by superplastic, GBS-limited creep, depending on the sample grain size. The deformed samples will then be imaged using cryogenic electron backscatter diffraction (cryo-EBSD) and high-angular-resolution electron backscatter diffraction (HR-EBSD) to quantify COF, grain size, grain shape, and crystal defect (dislocation) densities, among other microstructural properties. These measurements will be used to decipher the rate-controlling mechanisms operating within different thermomechanical regimes, and resolve a long-standing debate over whether superplastic creep can produce a COF in ice. In addition to the polycrystal experiments, ice bicrystals will be fabricated and deformed to investigate the micromechanical behavior of individual grain boundaries under superplastic conditions. Ultimately, these results will be used to provide a microstructural toolbox for identifying superplastic creep using geophysical (e.g., seismic, radar) and glaciological (e.g., ice core) observations. This project will support one graduate student, one or more undergraduate summer students, and an early-career researcher. In addition, this project will support a workshop aimed at bringing together experimentalists, glaciologists, and ice modelers to facilitate cross-disciplinary knowledge sharing and collaborative problem solving. 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.
Nontechnical Description: The age of rocks and soils at the surface of the Earth can help answer multiple questions that are important for human welfare, including: when did volcanoes erupt and are they likely to erupt again? when did glaciers advance and what do they tell us about climate? what is the frequency of hazards such as landslides, floods, and debris flows? how long does it take soils to form and is erosion of soils going to make farming unsustainable? One method that is used thousands of times every year to address these questions is called 'cosmogenic surface-exposure dating'. This method takes advantage of cosmic rays, which are powerful protons and neutrons produced by supernova that constantly bombard the Earth's atmosphere. Some cosmic rays reach Earth's surface and produce nuclear reactions that result in rare isotopes. Measuring the quantity of the rare isotopes enables the length of time that the rock or soil has been exposed to the atmosphere to be calculated. The distribution of cosmic rays around the globe depends on Earth's magnetic field, and this distribution must be accurately known if useful exposure ages are to be obtained. Currently there are two remaining theories, narrowed down from many, of how to calculate this distribution. Measurements from a site that is at both high altitude and high latitude (close to the poles) are needed to test the two theories. This study involves both field and lab research and includes a Ph.D. student and an undergraduate student. The research team will collect rocks from lava flows on an active volcano in Antarctica named Mount Erebus and measure the amounts of two rare isotopes: 36Cl and 3He. The age of eruption of the samples will be determined using a highly accurate method that does not depend on cosmic rays, called 40Ar/39Ar dating. The two cosmic-ray theories will be used to calculate the ages of the samples using the 36Cl and 3He concentrations and will then be compared to the ages calculated from the 40Ar/39Ar dating. The accurate cosmic-ray theory will be the one that gives the same ages as the 40Ar/39Ar dating. Identification of the accurate theory will enable use of the cosmogenic surface dating methods anywhere on earth. Technical Description: Nuclides produced by cosmic rays in rocks at the surface of the earth are widely used for Quaternary geochronology and geomorphic studies and their use is increasing every year. The recently completed CRONUS-Earth Project (Cosmic-Ray Produced Nuclides on Earth) has systematically evaluated the production rates and theoretical underpinnings of cosmogenic nuclides. However, the CRONUS-Earth Project was not able to discriminate between the two leading theoretical approaches: the original Lal model (St) and the new Lifton-Sato-Dunai model (LSD). Mathematical models used to scale the production of the nuclides as a function of location on the earth, elevation, and magnetic field configuration are an essential component of this dating method. The inability to distinguish between the two models was because the predicted production rates did not differ sufficiently at the location of the calibration sites. The cosmogenic-nuclide production rates that are predicted by the two models differ significantly from each other at Erebus volcano, Antarctica. Mount Erebus is therefore an excellent site for testing which production model best describes actual cosmogenic-nuclide production variations over the globe. The research team recently measured 3He and 36Cl in mineral separates extracted from Erebus lava flows. The exposure ages for each nuclide were reproducible within each flow (~2% standard deviation) and in very good agreement between the 3He and the 36Cl ages. However, the ages calculated by the St and LSD scaling methods differ by ~15-25% due to the sensitivity of the production rate to the scaling at this latitude and elevation. These results lend confidence that Erebus qualifies as a suitable high- latitude/high-elevation calibration site. The remaining component that is still lacking is accurate and reliable independent (i.e., non-cosmogenic) ages, however, published 40Ar/39Ar ages are too imprecise and typically biased to older ages due to excess argon contained in melt inclusions. The research team's new 40Ar/39Ar data show that previous problems with Erebus anorthoclase geochronology are now overcome with modern mass spectrometry and better sample preparation. This indicates a high likelihood of success for this proposal in defining an accurate global scaling model. Although encouraging, much remains to be accomplished. This project will sample lava flows over 3 km in elevation and determine their 40Ar/39Ar and exposure ages. These combined data will discriminate between the two scaling methods, resulting in a preferred scaling model for global cosmogenic geochronology. The LSD method contains two sub-methods, the 'plain' LSD scales all nuclides the same, whereas LSDn scales each nuclide individually. The project can discriminate between these models using 3He and 36Cl data from lava flows at different elevations, because the first model predicts that the production ratio for these two nuclides will be invariant with elevation and the second that there should be ~10% difference over the range of elevations to be sampled. Finally, the project will provide a local, finite-age calibration site for cosmogenic-nuclide investigations in Antarctica.
Anandakrishnan/1643961 This award supports a project to study conditions under the Rutford Ice Stream, a large glacier that flows from the interior of the West Antarctic Ice Sheet to the Filchner Ronne Ice Shelf and then on to the ocean. The speed and volume of ice delivered to the ocean by this and similar glaciers is central to the question of sea-level change in the coming decades: if the volume of ice carried by Rutford to the ocean increases, then it will contribute to a rise in sea level. Numerical models of glacier flow that are used to forecast future conditions must include a component that accounts for the sliding of the ice over its bed. The sliding process is poorly modeled because of lack of detailed information about the bottom of glaciers, leading to increased uncertainty in the ice-flow models. Data from this project will provide such information. During this project, in collaboration with researchers at the British Antarctic Survey, a detailed survey of the properties of the bed of Rutford Ice Stream will be carried out. These surveys include using seismic instruments (which are sensitive to naturally occurring earthquakes within glaciers--called icequakes) to monitor the distribution of those icequakes at the bed. The locations, size, and timing of icequakes are controlled by the properties of the bed such as porosity, water pressure, and stress. As part of this project, a hole will be drilled to the bed of the glacier to monitor water pressures and to extract a sample of the basal material. By comparing the pressure variations with icequake production, the properties of the basal material over a large area can be better determined. Those results will aid in the application of numerical models by informing their description of the sliding process. This award requires field work in Antarctica. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Adélie penguin (Pygoscelis adeliae) is the most abundant penguin in Antarctica, though its populations are currently facing threats from climate change, loss of sea ice habitat and food supplies. In the Ross Sea region, the cold, dry environment has allowed preservation of Adélie penguin bones, feathers, eggshell and even mummified remains, at active and abandoned colonies that date from before the Last Glacial Maximum (more than 45,000 years ago) to the present. A warming period at 4,000-2,000 years ago, known as the penguin ‘optimum’, reduced sea ice extent and allowed this species to access and reproduce in the southern Ross Sea. This coastline likely will be reoccupied in the future as marine conditions change with current warming trends. This project will investigate ecological responses in diet and foraging behavior of the Adélie penguin using well-preserved bones and other tissues that date from before, during and after the penguin ‘optimum’. The Principal investigators will collect and analyze bones, feathers and eggshells from colonies in the Ross Sea to determine changes in population size and feeding locations over millennia. Most of these colonies are associated with highly productive areas of open water surrounded by sea ice. Current warming trends are causing relatively rapid ecological responses by this species and some of the largest colonies in the Ross Sea are likely to be abandoned in the next 50 years from rising sea level. The recently established Ross Sea Marine Protected Area aims to protect Adélie penguins and their foraging grounds in this region from human impacts and knowledge on how this species has responded to climate change in the past will support this goal. This project benefits NSF’s mission to expand fundamental knowledge of Antarctic systems, biota, and processes. In association with their research program, the Principal Investigators will create undergraduate opportunities for research-driven coursework, will design K-12 curriculum and assess the effectiveness of these activities. Two graduate students will be supported by this project to update and refine the curricula working with K-12 teachers. There is also training and partial support included for one doctorate, two master and eight undergraduate students. General public will be reached through social media and YouTube channel productions. A suite of three stable isotopes (carbon, nitrogen, and sulfur) will be analyzed in Adelie penguin bones and feathers from active and abandoned colonies to assess ecological shifts through time. Stable isotope analyses of carbon and nitrogen (δ13C and δ15N) are commonly used to investigate animal migration, foraging locations and diet, especially in marine species that can travel over great distances. Sulfur (δ34S) is not as commonly used but is increasingly being applied to refine and corroborate data obtained from carbon and nitrogen analyses. Collagen is one of the best tissues for these analyses as it is abundant in bone, preserves well, and can be easily extracted for analysis. Using these three isotopes from collagen, ancient and modern penguin colonies will be investigated in the southern, central and northern Ross Sea to determine changes in populations and foraging locations over millennia. Most of these colonies are associated with one of three polynyas in the Ross Sea. This study will be the first of its kind to apply multiple stable isotope analyses to investigate a living species of seabird over millennia in a region where it still exists today. Results from this project will also inform management on best practices for Adelie penguin conservation affected by climate change. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Estimating Antarctic ice sheet growth or loss is important to predicting future sea level rise. Such estimates rely on field measurements or remotely sensed based observations of the ice sheet surface, ice margins, and or ice shelves. This work examines the introduction of freshwater into the ocean to surrounding Antarctica to track meltwater from continental ice. Polar ice is depleted in two stable isotopes, 18O and D, deuterium, relative to Southern Ocean seawater and precipitation. Measurements of seawater isotopic composition in conjunction with precise observations of seawater temperature and salinity, will permit discrimination of freshwater derived from melting glacial ice from that derived from regional precipitation or sea ice melt. This research describes an accepted method for determining rates and locations of meltwater entering the oceans from polar ice sheets. As isotopic and salinity perturbations are cumulative in many Antarctic coastal seas, the method allows for the detection of any marked acceleration in meltwater introduction in specific regions, using samples collected and analyzed over a period of years to decades. Impact of the project derives from use of an independent method capable of constraining knowledge about current ice sheet melt rates, their stability and potential impact on sea level rise. The project allows for sample collection taken from foreign vessels of opportunity sailing in Antarctic waters, and subsequent sharing and interpretation of data. Research partners include the U.S., Korea, China, New Zealand, the United Kingdom, and Germany. Participating collaborators will collect seawater samples for isotopic and salinity analysis at Stanford University. USAP cruises will concentrate on sampling the Ross Sea, and the West Antarctic. The work plan includes interpretation of isotopic data using box model and mixing curve analyses as well as using isotope enabled ROMS (Regional Ocean Modeling System) models. The broader impacts of the research will include development of an educational module that illustrates the scientific method and how ocean observations help society understand how Earth is changing.
Ice cores are a vital source of information about past climate. Research that utilizes ice cores benefits from an undamaged ice-core record. There is often a zone within ice sheets where the ice is brittle upon extraction in a core. Brittle-ice behavior occurs when the rapid decompression of the core as it is being extracted from the ice-sheet results in extensive fracturing. Ice from this zone can compromise the undamaged record. This project seeks to improve our understanding of the mechanisms involved in brittle-ice behavior and onset, with the goal of helping to guide field-site operations, core handling preparation, and planned laboratory measurement techniques for future ice-coring projects, including the upcoming work at Hercules Dome. This project requires no field work, as it will use existing observations and existing ice cores to gain an understanding of brittle ice. This is a high-risk and timely proposal that is early-concept and exploratory in nature, making it appropriate for the EAGER solicitation. The project will support an early-career researcher and provide training for a master’s student who is a woman. And, finally, the project will develop educational and outreach materials for graduate and undergraduate courses and elementary schools. This project will examine and catalog brittle ice from several existing ice-core samples to specifically assess various ice physical properties affecting brittleness potential, including bubble size and number-density, ice fabric, grain statistics, fracture characteristics, and the location and properties of grain and subgrain boundaries. End members of this sample assessment have been identified and include Siple Dome, which exhibited major brittle behavior and damage, and South Pole ice core, which exhibited very-minor brittle behavior and almost no damage. Output datasets will include calibrated relationships for bubble number-density, mean grain and bubble sizes, subgrain prevalence and orientation, and a usable indicator for estimating brittle-ice onset and magnitude. There is an immediate applicability of results from this effort for the Hercules Dome drilling 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.
Within any population, some individuals perform better than others. These individuals may survive longer or produce more offspring. Weddell seals in Erebus Bay, Antarctica, provide an unparalleled opportunity to investigate how an animal's physiology, behavior, and genetic make-up contribute to lifetime reproductive success because they have been the subject of a long-term population monitoring study and are easily accessible during their reproductive season. This project will distinguish key differences in energy allocation, reproductive timing, and dive capacities between female Weddell seals with a history of frequently producing pups ("high-quality" group), versus females that have produced pups only infrequently ("low-quality" group). For each group of females, physiology and behavior during the nursing period will be analyzed to assess whether investments influence their probability of reproducing the following year. Whole genomes will be compared between groups to identify underlying genes that govern reproductive success and population stability in a long-lived mammal. This collaborative project will provide research opportunities and training to several undergraduate and graduate students at the three participating institutions. Results will be broadly disseminated through presentations and peer-reviewed publications, and to students via an extensive public outreach collaboration with museum programming, curriculum-aligned science lessons, and pedagogy training. Within any wild animal population there is substantial heterogeneity in reproductive rates and animal fitness. Not all individuals contribute to the population equally; some are able to produce more offspring than others and thus are considered to be of higher quality. This study aims to distinguish which physiological mechanisms (energy dynamics, aerobic capacity, and fertility) and underlying genetic factors make some Weddell seal females particularly successful at producing pups year after year, while others produce far fewer pups than the population average. In this project, an Organismal Energetics approach will identify key differences between high- and low-quality females in how they balance current and future reproductive success by tracking lactation costs, midsummer foraging success and pregnancy rates, and overwinter foraging patterns and live births the next year. Repeated sampling of individuals' physiological status (body composition, endocrinology, ovulation and pregnancy timing), will be paired with a whole-genome sequencing study. The second component of this study uses a Genome to Phenome approach to better understand how genetic differences between high- and low-quality females directly correspond to functional differences in transcription, translation, and ultimately phenotype. This component will contribute to the functional analysis and annotation of the Weddell seal genome. In combination, this project will make strides towards distinguishing the roles that plastic (physiological, behavioral) and fixed (genetic) factors play in complex, multifaceted traits such as fitness in a long-lived wild mammal. The project partners with established programs to implement extensive educational and outreach activities that will ensure wide dissemination to educators, students, and the public. It will contribute to a marine mammal exhibit at the Pink Palace Museum, and a PolarTREC science educator will participate in field work in Antarctica. This award is co-funded by the GEO-OPP-Antarctic Organisms and Ecosystems Program, BIO-IOS-Physiological Mechanisms and Biomechanics Program, and the Established Program to Stimulate Competitive Research (EPSCoR). This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The response of the Antarctic ice sheet to climate change is a central issue in projecting global sea-level rise. While much attention is focused on the ongoing rapid changes at the coastal margin of the West Antarctic Ice Sheet, obtaining records of past ice-sheet and climate change is the only way to constrain how an ice sheet changes over millennial timescales. Whether the West Antarctic Ice Sheet collapsed during the last interglacial period (~130,000 to 116,000 years ago), when temperatures were slightly warmer than today, remains a major unsolved problem in Antarctic glaciology. Hercules Dome is an ice divide located at the intersection of the East Antarctic and West Antarctic ice sheets. It is ideally situated to record the glaciological and climatic effects of changes in the West Antarctic Ice Sheet. This project will establish whether Hercules Dome experienced major changes in flow due to changes in the elevation of the two ice sheets. The project will also ascertain whether Hercules Domes is a suitable site from which to recover climate records from the last interglacial period. These records could be used to determine whether the West Antarctic Ice Sheet collapsed during that period. The project will support two early-career researchers and train students at the University of Washington. Results will be communicated through outreach programs in coordination the Ice Drilling Project Office, the University of Washington's annual Polar Science Weekend in Seattle, and art-science collaboration. This project will develop a history of ice dynamics at the intersection of the East and West Antarctic ice sheets, and ascertain whether the site is suitable for a deep ice-coring operation. Ice divides provide a unique opportunity to assess the stability of past ice flow. The low deviatoric stresses and non-linearity of ice flow causes an arch (a "Raymond Bump") in the internal layers beneath a stable ice divide. This information can be used to determine the duration of steady ice flow. Due to the slow horizontal ice-flow velocities, ice divides also preserve old ice with internal layering that reflects past flow conditions caused by divide migration. Hercules Dome is an ice divide that is well positioned to retain information of past variations in the geometry of both the East and West Antarctic Ice Sheets. This dome is also the most promising location at which to recover an ice core that can be used to determine whether the West Antarctic Ice Sheet collapsed during the last interglacial period. Limited ice-penetrating radar data collected along a previous scientific surface traverse indicate well-preserved englacial stratigraphy and evidence suggestive of a Raymond Bump, but the previous survey was not sufficiently extensive to allow thorough characterization or determination of past changes in ice dynamics. This project will conduct a dedicated survey to map the englacial stratigraphy and subglacial topography as well as basal properties at Hercules Dome. The project will use ground-based ice-penetrating radar to 1) image internal layers and the ice-sheet basal interface, 2) accurately measure englacial attenuation, and 3) determine englacial vertical strain rates. The radar data will be combined with GPS observations for detailed topography and surface velocities and ice-flow modeling to constrain the basal characteristics and the history of past ice flow. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). An important part of understanding future climate change is predicting changes in how fast the ice in Antarctica is moving. If ice flows more quickly towards the ocean, it will have a direct impact on sea level rise. One of the things that can influence the ice flow is the type of rock below the ice coverage in Antarctica. Sedimentary basins are large regions where sedimentary rocks accumulated in the past, often under ancient seas. It has been observed that where there are sediments below the ice, the ice can flow faster. This project seeks to understand what is below the ice and how the underlying rock influences the ice flow. Is it hard, crystalline rock? Is it a sedimentary basin? What is the relationship between sediments and ice flow? The answers to these questions will be addressed by using a combination of available data and geophysical methods. Information from well-known rock-types will be used to train the computer to recognize these features by using an application of artificial intelligence known as machine learning, which will help the characterization and identification of unknown sedimentary basins beneath the ice. The results of this project will be disseminated to a broad audience by holding workshops for teacher and students to explain our findings under the ice and to introduce the machine learning technique. Open-source codes used during this project will be made available for use in higher-level classrooms as well as in further studies. To date, no comprehensive distribution of onshore and offshore sedimentary basins over Antarctica has been developed. A combination of large-scale datasets will be used to characterize known basins and identify new sedimentary basins to produce the first continent-wide mapping of sedimentary basins and provide improved basal parametrizations conditions that have the potential to support more realistic ice sheet models. Available geophysical compilations of data and the location of well-known sedimentary basins will be used to apply an ensemble machine learning algorithm. The machine learning algorithm will learn complex relationships by voting among a collection of randomized decision trees. The gravity signal related to sedimentary basins known from other (e.g. seismic) techniques will be evaluated and unknown basins from aerogravity data regression analyses will be proposed by calculating a gravity residual that reflects density inhomogeneities. The gravimetric sedimentary basins identified from the regression analyses will be compared with an independent method of identifying sedimentary distribution, the Werner deconvolution method of estimating depth to magnetic sources. The hypothesis, which is sedimentary basins are correlated to fast ice flow behavior, will be tested by comparing the location of the sedimentary basins with locations of high ice flow by using available ice velocity observations. A relationship between sedimentary basins and ice streams will be defined qualitatively and quantitatively, aiming to evaluate if there are ice streams where no sedimentary basins are reported, or sedimentary basins with no ice streams related. The findings of these project can confirm if the presence of abundant sediments is a pre-requisite for ice streaming. Analyzing previously known sedimentary basins and identifying new ones in Antarctica is central to evaluating the influence of subglacial sediments on the ice sheet flow. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Pygoscelis penguins are central place foragers during the summer while they raise their chicks. They leave and return to the same colony location after hunting for food and rely on the availability of Antarctic krill, their primary food source. This research focuses on whether penguin diets and colony location reflect the retention of prey around and near colonies on the West Antarctic Peninsula. Eddies and other oceanographic processes may facilitate prey retention at certain locations, driving penguin colony establishment and success. This project hypothesizes that Pygoscelis penguin diets will be composed of more Antarctic krill (Euphausia superba) when local prey retention is high, possibly due to subsurface eddies. This hypothesis will be tested using satellite-based estimates of Pygoscelis penguin diet composition using multispectral sensor data to estimate nitrogen values and infer trophic level. Prey retention will be calculated along the peninsula using the Regional Ocean Modeling System (ROMS). Simulated particles and diel vertical migration will be used to mimic krill behavior. These particles can be experimentally seeded across multiple depths in multiple years to assess residence times in the system. Using penguin colony data from the Mapping Application for Penguin Populations and Projected Dynamics (MAPPPD), the PI will correlate diet and retention metrics to local penguin colony growth and persistence and build a predictive model of where colonies may form in the future. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This research project will use specially designed autonomous underwater vehicles (AUVs) to investigate interactions between Adelie and Gentoo penguins (the predators) and their primary food source, Antarctic krill (prey). While it has long been known that penguins feed on krill, details about how they search for food and target individual prey items is less well understood. Krill aggregate in large swarms, and the size or the depth of these swarms may influence the feeding behavior of penguins. Similarly, penguin feeding behaviors may differ based on characteristics of the environment, krill swarms, and the presence of other prey and predator species. This project will use specialized smart AUVs to simultaneously collect high-resolution observations of penguins, their prey, and environmental conditions. Data will shed light on strategies used by penguins prove foraging success during the critical summer chick-rearing period. This will improve predictions of how penguin populations may respond to changing environmental conditions in the rapidly warming Western Antarctic Peninsula region. Greater understanding of how individual behaviors shape food web structure can also inform conservation and management efforts in other marine ecosystems. This project has a robust public education and outreach plan linked with the Birch and Monterey Bay Aquariums. Previous studies have shown that sub-mesoscale variability (1-10 km) in Antarctic krill densities and structure impact the foraging behavior of air-breathing predators. However, there is little understanding of how krill aggregation characteristics are linked to abundance on fine spatial scales, how these patterns are influenced by the habitat, or how prey characteristics influences the foraging behavior of predators. These data gaps remain because it is extremely challenging to collect detailed data on predators and prey simultaneously at the scale of an individual krill patch and single foraging event. Building on previously successful efforts, this project will integrate echosounders into autonomous underwater vehicles (AUVs), so that oceanographic variables and multi-frequency acoustic scattering from both prey and penguins can be collected simultaneously. This will allow for quantification of the environment at the scale of individual foraging events made by penguins during the critical 50+ day chick-rearing period. Work will be centered near Palmer Station, where long-term studies have provided significant insight into predator and prey population trends. The new data to be collected by this project will test hypotheses about how penguin prey selection and foraging behaviors are influenced by physical and biological features of their ocean habitat at extremely fine scale. By addressing the dynamic relationship between individual penguins, their prey, and habitat at the scale of individual foraging events, this study will begin to reveal the important processes regulating resource availability and identify what makes this region a profitable foraging habitat and breeding location. 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.
Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function. To understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This project will conduct basic research into geological dating techniques that are useful for determining the age of glacial deposits in polar regions, Antarctica in particular. These techniques are necessary for determining how large the polar ice sheets were in the geologic past, including during past periods of warm climate that likely resemble present and near-future conditions. Thus, they represent an important technical capability needed for estimating the response of polar ice sheets to climate warming. Because changes in the size of polar ice sheets are the largest potential contribution to future global sea-level change, this capability is also relevant to understanding likely sea-level impacts of future climate change. The research in this project comprises several observational and experimental approaches to improving the speed, efficiency, cost, and accuracy of these techniques, as well as a scientific outreach program aimed at making the resulting capabilities more broadly available to other researchers. The project supports a postdoctoral scholar and contributes to human resources development in polar and climate science. The project focuses on several areas of cosmogenic-nuclide geochemistry, which is a geochemical dating method that relies on the production and decay of cosmic-ray-produced radionuclides in surface rocks. Measurements of these nuclides can be used to quantify the duration of surface exposure and ice cover at locations in Antarctica that are covered and uncovered by changes in the size of the Antarctic ice sheets, thus providing a means of reconstructing past ice-sheet change. The first proposed set of experiments are aimed at implementing a 'virtual mineral separation' approach to cosmogenic noble gas analysis that may allow measurement of nuclide concentrations in certain minerals without physically separating the minerals from the host rock. If feasible, this would realize significant speed and cost improvements for this type of analysis. A second set of experiments will focus on means of identifying and quantifying non-cosmogenic background inventories of some relevant nuclides, which is intended to improve the measurement sensitivity and precision for cosmic-ray-produced inventories of these nuclides. A third focus area aims to improve capabilities to measure multiple cosmic-ray-produced nuclides in the same sample, which has the potential to improve the accuracy of dating methods based on these nuclides and to expand the situations in which these methods can be applied. If successful, these experiments are likely to improve a number of applications of cosmogenic-nuclide geochemistry relevant to Antarctic research, including subglacial bedrock exposure dating, dating of multimillion-year-old glacial deposits, and surface-process studies useful in understanding landform evolution and ecosystem dynamics. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The western portion of the Antarctic continent is very active in terms of plate tectonic processes that can produce significant variations in the Earths mantle temperature as well as partial melting of the mantle. In addition to these internal processes, the ice sheet in western Antarctica is melting due to Earths warming climate and adding water to the ocean. These changes in ice mass cause adjustments in rocks within the Earth's crust, allowing the surface to rebound in some locations and fall in others, altering the geographical pattern of sea-level change. However, the solid Earth response depends strongly on the strength of the rocks at a wide range of timescales which is not well-known and varies with temperature and other rock properties. This project has three primary goals. (1) It will assess how processes such as rifting, mantle upwelling and lithospheric instability have altered the lithosphere and underlying asthenosphere of western Antarctica, contributing to a planet-wide understanding of these processes. (2) It will use new measurements of mantle and crust properties to estimate the rate at which heat from the solid Earth flows into the base of the ice, which is important for modeling the rates at which the ice melts and flows. (3) It will places bounds on mantle viscosity, which is key for modeling the interaction of the solid Earth with changing ice and water masses and their implications for sea-level rise. To accomplish these goals, new resolution of crust and mantle structure will be obtained by analyzing seismic waves from distant earthquakes that have been recorded at numerous seismic stations in Antarctica. These analyses will include new combinations of seismic wave data that provide complementary information about mantle temperature, heat flow and viscosity. This project will provide educational and career opportunities to a Brown University graduate student, undergraduates from groups underrepresented in science who will come to Brown University for a summer research program, and other undergraduates. The project will bring together faculty and students for a seminar at Brown that explores the connections between the solid Earth and ice processes in Antarctica. Project research will be incorporated in outreach to local public elementary schools and high schools. This research addresses key questions about mantle processes and properties in western Antarctica. What are the relative impacts of rifting, mantle plumes, and lithospheric delamination in the evolution of the lithosphere and asthenosphere? Where is topography isostatically compensated, and where are dynamic processes such as plate flexure or tractions from 3-D mantle flow required? What are the bounds on heat flow and mantle viscosity, which represent important inputs to models of ice sheet evolution and its feedback from the solid Earth? To address these questions, this project will measure mantle and crust properties using seismic tools that have not yet been applied in Antarctica: regional-scale measurement of mantle attenuation from surface waves; Sp body wave phases to image mantle velocity gradients such as the lithosphere-asthenosphere boundary; and surface wave amplification and ellipticity. The resulting models of seismic attenuation and velocity will be jointly interpreted to shed new light on temperature, bulk composition, volatile content, and partial melt, using a range of laboratory-derived constitutive laws, while considering data from mantle xenoliths. To test the relative roles of rifting, mantle plumes, and delamination, and to assess isostatic support for Antarctic topography, the predictions of these processes will be compared to the new models of crust and mantle properties. To improve bounds on western Antarctic heat flow, seismic attenuation and velocity will be used in empirical comparisons and in direct modeling of vertical temperature gradients. To better measure mantle viscosity at the timescales of glacial isostatic adjustment, frequency-dependent viscosity will be estimated from the inferred mantle conditions. This project will contribute to the education and career development of the following: a Brown University Ph.D. student, Brown undergraduates, and undergraduates from outside the university will be involved through the Department of Earth, Environmental and Planetary Sciences (DEEPS) Leadership Alliance NSF Research Experience for Undergraduates (REU) Site which focuses on geoscience summer research experiences for underrepresented students. The project will be the basis for a seminar at Brown that explores the connections between the solid Earth and cryosphere in Antarctica and will contribute to outreach in local public elementary and high schools. 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.
Alabama Museum of Natural History, University of Alabama, Tuscaloosa
Ocean communities play an important role in determining the natural and human impacts of global change. The most conspicuous members of those communities are generally large vertebrates such as marine mammals and sea birds. But smaller animals often determine how the changes impact those charismatic animals. In the Antarctic, where some of the most dramatic physical changes are taking place, we do not know much about what small animals exist. This project will sample the sub-Antarctic and three different Antarctic seas with a hope of identifying, quantifying and discovering the variation in species of a group of small invertebrates. Comma shrimp, also called cumaceans, are rarely seen elsewhere but may be common and important in the communities of these locations. Antarctic sampling traditionally used gear that was not very effective at catching cumaceans so we do not know what species exist there and how common they are. This study will utilize modern sampling methods that will allow comma shrimp to be sampled. This will lead to discoveries about the diversity and abundance of comma shrimp, as well as their relationship to other invertebrate species. Major impacts of this work will be an enhancement of museum collections, the development of description of all the comma shrimp of Antarctica including new and unnamed species. Those contributions may be especially important as we strive to understand what drives the dynamics of charismatic vertebrates and fisheries that are tied to Antarctic food webs. This project will collect cumaceans from benthic samples from Argentinian waters, Bransfield Strait, and the Weddell Sea using benthic sleds. Specimens will be fixed in 95% ethanol and preserved in 95% ethanol and 5% glycerin to preserve both morphology and DNA. The specimens will form the basis for a monograph synthesizing current knowledge on the Subantarctic and Antarctic Cumacea, including diagnoses of all species, descriptions of new species, additional description for currently unknown life stages of known species, and vouchered gene sequences for all species collected. The monograph will include keys to all families, genera and species known from the region. Monographic revisions that include identification resources are typically useful for decades to a broad spectrum of other scientists. 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.
Climate change is changing the number of sea-ice free days in coastal polar environments, which is impacting Antarctic communities. This study will evaluate the change in macroalgae (seaweed) communities to increased light availability in order to predict if macroalgae will be able to spread to newly ice-free locations faster than invertebrates (e.g., sponges, bryozoans, tunicates, and polychaetes) in shallow underwater rocky habitats. Study sites will include multiple locations in McMurdo Sound, Ross Sea, Antarctica. This study will establish patterns in plant properties, genetic diversity and reproductive characteristics of two species of seaweeds, Phyllophora antarctica and Iridaea cordata in relation to depth and light. Long-term changes will be assesed by comparing to results from a survey in 1980. This will be the first study in the region to estimate the potential effects of climate, in particular reductions in annual sea ice cover and resulting increase in light intensity and duration, on shifts in macroalgal communities in McMurdo Sound. Three-dimensional photogrammetry will also be used to evaluate benthic community structure on the newly discovered offshore Dellbridge Seamount. Visualization from the video footage will be shared with web-based interactive applications to engage and educate the public in polar ecology and factors causing changes in marine community ecosystem structure in this important region. This project is evaluating macroalgae biogeography in Antarctic coastal waters near McMurdo Sound, a relatively understudied region that is experiencing large changes in fast sea ice coverage. The population ecology and genetic diversity of nearshore shallow and deeper offshore benthic macroalgal communities of Phyllophora antarctica and Iridaea cordata will be assessed for percentage cover, biomass, blade length, and reproductive characteristics at seven locations: Cape Royds, Cape Evans, Little Razorback Islands, Turtle Rock, Arrival Heights, Granite Harbor, and Dellbridge Seamount in McMurdo Sound, Antarctica. The team is also assessing differential reproductive successes at different depths and comparing results to populations surveyed in 1980. The genetic diversity of the two species is being estimated using a combination of whole genome sequencing and species-specific microsatellite genetic markers. Samples from this study will be compared to samples collected from other regions in Antarctica such as the South Shetland Islands and Antarctic Peninsula. In addition, a macroalgal assemblage and 3D models of the community structure will be generated using photogrammetry from the newly discovered Dellbridge Seamount that is located 2 km offshore in McMurdo Sound. With the addition of photogrammetry and 3D visualization to this research, web-based applications will be used to engage and educate the public in subtidal polar ecology, population genetics, and the importance of Antarctic science to their lives. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Cores drilled through the Antarctic ice sheet provide a remarkable window on the evolution of Earth’s climate and unique samples of the ancient atmosphere. The clear link between greenhouse gases and climate revealed by ice cores underpins much of the scientific understanding of climate change. Unfortunately, the existing data do not extend far enough back in time to reveal key features of climates warmer than today. COLDEX, the Center for Oldest Ice Exploration, will solve this problem by exploring Antarctica for sites to collect the oldest possible record of past climate recorded in the ice sheet. COLDEX will provide critical information for understanding how Earth’s near-future climate may evolve and why climate varies over geologic time. New technologies will be developed for exploration and analysis that will have a long legacy for future research. An archive of old ice will stimulate new research for the next generations of polar scientists. COLDEX programs will galvanize that next generation of polar researchers, bring new results to other scientific disciplines and the public, and help to create a more inclusive and diverse scientific community. Knowledge of Earth’s climate history is grounded in the geologic record. This knowledge is gained by measuring chemical, biological and physical properties of geologic materials that reflect elements of climate. Ice cores retrieved from polar ice sheets play a central role in this science and provide the best evidence for a strong link between atmospheric carbon dioxide and climate on geologic timescales. The goal of COLDEX is to extend the ice-core record of past climate to at least 1.5 million years by drilling and analyzing a continuous ice core in East Antarctica, and to much older times using discontinuous ice sections at the base and margin of the ice sheet. COLDEX will develop and deploy novel radar and melt-probe tools to rapidly explore the ice, use ice-sheet models to constrain where old ice is preserved, conduct ice coring, develop new analytical systems, and produce novel paleoclimate records from locations across East Antarctica. The search for Earth’s oldest ice also provides a compelling narrative for disseminating information about past and future climate change and polar science to students, teachers, the media, policy makers and the public. COLDEX will engage and incorporate these groups through targeted professional development workshops, undergraduate research experiences, a comprehensive communication program, annual scientific meetings, scholarships, and broad collaboration nationally and internationally. COLDEX will provide a focal point for efforts to increase diversity in polar science by providing field, laboratory, mentoring and networking experiences for students and early career scientists from groups underrepresented in STEM, and by continuous engagement of the entire COLDEX community in developing a more inclusive scientific culture. 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.
Understanding and being able to more reliably forecast ice mass loss from Antarctica is a critical research priority for Antarctic Science. Massive ice shelves buttress marine terminating glaciers, slowing the rate that land ice reaches the sea and, in turn, restraining the rate of sea level rise. To date, most work has focused on the destabilizing impacts of warmer air and water temperatures, resulting in melting that thins and weakens ice shelves. However, recent findings indicate that sea ice does not protect ice shelves from wave impacts as much as previously thought, which has raised the possibility that tsunamis and other ocean waves could affect shelf stability. This project will assess the potential for increased shelf fracturing from the impact of tsunamis and from heightened wave activity due to climate-driven changes in storm patterns and reduced sea-ice extent by developing models to investigate how wave impacts damage ice shelves. The modeling effort will allow for regional comparisons between large and small ice shelves, and provide an evaluation of the impacts of changing climate and storm patterns on ice shelves, ice sheets, glaciers, and, ultimately, sea level rise. This project will train graduate students in mathematical modeling and interdisciplinary approaches to Earth and ocean sciences. This project takes a four-pronged approach to estimating the impact of vibrations on ice shelves at the grounding zone due to tsunamis, very long period, infragravity, and storm-driven waves. First, the team will use high-resolution tsunami modeling to investigate the response of ice shelves along the West Antarctic coast to waves originating in different regions of the Pacific Ocean. Second, it will compare the response to wave impacts on grounding zones of narrow and wide ice shelves. Third, it will assess the exposure risk due to storm forcing through a reanalysis of weather and wave model data; and, finally, the team will model the propagation of ocean-wave-induced vibrations in the ice from the shelf front to and across the grounding zone. In combination, this project aims to identify locations along the Antarctic coast that are subject to enhanced, bathymetrically-focused, long-period ocean-wave impacts. Linkages between wave impacts and climate arise from potential changes in sea-ice extent in front of shelves, and changes in the magnitude, frequency, and tracks of storms. Understanding the effects of ocean waves and climate on ice-shelf integrity is critical to anticipate their contribution to the amplitude and timing of sea-level rise. Wave-driven reductions in ice-shelf stability may enhance shelf fragmentation and iceberg calving, reducing ice shelf buttressing and eventually accelerating sea-level rise. 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.
Salvatore, Mark; Gooseff, Michael N.; Sokol, Eric; Barrett, John
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Part I: Non-technical description: Water is life and nowhere is it more notable than in deserts. Within the drylands on Earth, the Antarctic deserts, represented in this study by the McMurdo Dry Valleys, exemplify life in extreme environments with scarce water, low temperatures and long periods of darkness during the polar winter. There is a scarcity of methods to determine water availability, data necessary to predict which species are successful in the drylands, unless measurements are done manually or with field instruments. This project aims to develop a new method of determining soil moisture and use the new data to identify locations suitable for life. Combining these habitats with known species distributions in the McMurdo Dry Valleys, results from this project will predict which species should be present, and also what is the expected species distribution in a changing environment. In this way the project takes advantage of a combination of methods, from recent remote sensing products, ecological models and 30 years of field collections to bring a prediction of how life might change in the McMurdo Dry Valleys in a warmer, and possibly, moister future climate. This project benefits the National Science Foundation goals of expanding fundamental knowledge of Antarctic biota and the processes that sustain life in extreme environments. The knowledge acquired in this project will be disseminated to other drylands through training of high-school curricular programming in Native American communities of the SouthWest. Part II: Technical description: Terrestrial environments in Antarctica are characterized by low liquid water supply, sub-zero temperatures and the polar night in winter months. During summer, melting of snow patches, seasonal steams from glacial melt and vicinity to lakes provide a variety of environments that maintain life, not yet studied at landscape-scale level for habitat suitability and the processes that drive them. This project proposes to integrate remote sensing, hydrological models and ecological models to establish habitat suitability for species in the McMurdo Dry Valleys based on water availability. The approach is at a landscape level in order to establish present-day and future scenarios of species distribution. There are four main objectives: remote sensing development of moisture levels in soils, combining biological and soil data, building and calibrating models of habitat suitability by combining species distribution and environmental variability and applying statistical species distribution model. The field data to develop habitat suitability and calibration of models will leverage a the 30-year dataset collected by the McMurdo Long-Term Ecological Research program. Mechanistic models developed will be essential to predict species distribution in future climate scenarios. Training of post-doctoral researchers and a graduate student will prepare for the next generation of Antarctic scientists. Results from this project will train high-school students from native American communities in the SouthWest where similar desert conditions exist. 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.
Dunbar/1543454 Antarctic ice cores offer unparalleled records of earth?s climate back to almost one million years and perhaps beyond. Layers of volcanic ash (tephra) embedded in glacial ice can be used to establish an accurate ice core chronology. In order to use a visible or ultrafine volcanic ash layer as a time-stratigraphic marker, a unique geochemical fingerprint must be established, and this forms the basis of our research. This award will investigate the volcanic record in the 1751 m ice core that was completed at the South Pole during the 2015/16 field season. The core is in an ideal location to link the existing, established, volcanic records in East and West Antarctica, and therefore to connect and integrate those records, allowing the climate records of ice cores to be directly compared, as well as to focus research on the most widespread and significant volcanic eruptions from West Antarctica. Tephra derived from well-dated, large, tropical volcanic eruptions that may have had an impact on climate will also be studied. Recent success in identifying and analyzing very fine ash particles from these types of eruptions makes it likely that we will be able to pinpoint some of these eruptions, which will allow the sulfate peaks associated with these layers to be positively identified and dated. Volcanic forcing time series developed from earlier South Pole ice cores based on preserved sulfate were crucial for testing climate models, but without tephra analysis, the origin of these layers remains uncertain. Work on the tephra layers in the South Pole ice core has a number of significant specific objectives, some with practical applications to the basic science goals of Antarctic ice coring, and others that represent independent scientific contributions in their own right. These include: (1) providing independently dated time-intervals in the core, particularly for the deepest ice, (2) quantitatively linking tephra records across Antarctica with the goal of allowing direct and robust climate comparisons between these different parts of the continent, (3) providing information for large local eruptions, that will lead to direct estimates of eruption magnitude and dispersal patterns of Antarctic volcanoes, several of which will likely erupt again. The initial stages of the work will be carried out by identifying silicate-bearing horizons in the ice core, using several methods. Once found, silicate particles will be imaged so that morphological characteristics of the particles can be used to identify volcanic origin. Particles identified as tephra will then be chemically analyzed using electron microprobe and laser ablation ICP-MS. Samples that yield a robust chemical fingerprint will be statistically correlated to known eruptions, and this will be used to address the goals described above. Broader impacts of this project fall into the areas of education of future generation of researchers, outreach and international cooperation. These activities will continue to promote forward progress in integrating the Antarctic tephra record and more broadly tying it to the global volcanic record.
Correlating ecosystem responses to past climate forcing is highly dependent on the use of reliable techniques for establishing the age of events (dating techniques). In Antarctic dry regions (land areas without glaciers), carbon-14 dating has been used to assess the ages of organic deposits left behind by ancient lakes. However, the reliability of the ages is debatable because of possible contamination with "old carbon" from the surrounding landscape. The proposed research will attempt to establish two alternate dating techniques, in situ carbon-14 cosmogenic radionuclide exposure dating and optically stimulated luminescence (OSL), as reliable alternate dating methods for lake history in Antarctic dry areas that are not contaminated by the old carbon. The end goal will be to increase scientific understanding of lake level fluctuation in the lakes of Taylor Valley, Antarctica so that inference about past climate, glacier, and ecosystem response can be inferred. The results of this study will provide a coarse-scale absolute chronology for lake level history in Taylor Valley, demonstrate that exposure dating and OSL are effective means to understand the physical dynamics of ancient water bodies, and increase the current understanding of polar lacustrine and ice sheet responses to past and present climatic changes. These chronologies will allow polar lake level fluctuations to be correlated with past changes in global and regional climate, providing information critical for understanding and modeling the physical responses of these environments to modern change. This research supports a PhD student; the student will highlight this work with grade school classes in the United States. This research aims to establish in situ carbon-14 exposure dating and OSL as reliable alternate (to carbon-14 of organic lake deposits) geochronometers that can be used to settle the long-disputed lacustrine history and chronology of Taylor Valley, Antarctica and elsewhere. Improved lake level history will have significant impacts for the McMurdo Dry Valleys Long Term Ecological Research (MCM LTER) site as the legacy of fluctuating lake levels of the past affects the distribution of organic matter and nutrients, and impacts biological connectivity valley-wide. This work will provide insight into the carbon reservoir of large glacial lakes in the late Holocene and have implications for previously reported radiocarbon chronologies. OSL samples will be analyzed in the Desert Research Institute Luminescence Laboratory in Reno, NV. For the in situ carbon-14 work, rock samples extracted from boulders and bedrock surfaces will be prepared at Tulane University. The prepared in situ carbon-14 samples will be analyzed at the National Ocean Sciences Accelerator Mass Spectrometry laboratory in Woods Hole, MA. The two datasets will be combined to produce a reliable, coarse scale chronology for late Quaternary lake level fluctuations in Taylor Valley. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Antarctic Ice Sheet stability remains a large uncertainty in predicting future sea level. Presently, the greatest ice mass loss is observed in locations where relatively warm water comes into contact with glaciers and ice shelves, melting them from below. This has led researchers to hypothesize that the interactions that occur between the ocean and the ice are important for determining ice sheet stability and that increased warm water presence will accelerate Antarctic ice mass loss and lead to greater sea level rise in the coming century. To better predict future ice sheet behavior, it is critical to understand past ice-ocean interactions around Antarctica, especially during warm periods and at times when Earth’s climate was undergoing major changes. Past Antarctic ice mass and environmental conditions like ocean temperature can be reconstructed using sediments, which capture an environmental record as they accumulate on the ocean floor. By looking at sediment composition and by analyzing geochemical signatures within the sediment, it is possible to piece together a record of climate change on hundred- to million-year timescales. This project will reconstruct upper ocean temperatures and Antarctic ice retreat/advance cycles from 2.6 to 0.7 million years ago, which encompasses the Mid-Pleistocene Transition, a time in Earth’s history that marks the shift from 41-thousand year glacial cycles to 100-thousand year glacial cycles. A record will be generated from existing sediment cores collected from the Scotia Sea during International Ocean Discovery Program Expedition 382. The Mid-Pleistocene Transition (MPT; ~1.25–0.7 Ma) marks the shift from glacial-interglacial cycles paced by obliquity (~41 kyr cycles) to those paced by eccentricity (~100-kyr cycles). This transition occurred despite little variation in Earth’s orbital parameters, suggesting a role for internal climate feedbacks. The MPT was accompanied by decreasing atmospheric pCO2, increasing deep ocean carbon storage, and changes in deep water formation and distribution, all of which are linked to Antarctic margin atmosphere-ice-ocean interactions. However, Pleistocene records that document such interactions are rarely preserved on the shelf due to repeated Antarctic Ice Sheet (AIS) advance; instead, they are preserved in deep Southern Ocean basins. This project takes advantage of the excellent preservation and recovery of continuous Pleistocene sediment sequences collected from the Scotia Sea during International Ocean Discovery Program Expedition 382 to test the following hypotheses: 1) Southern Ocean upper ocean temperatures vary on orbital timescales during the early to middle Pleistocene (2.6–0.7 Ma), and 2) Southern Ocean temperatures co-vary with AIS advance/retreat cycles. Paleotemperatures will be reconstructed using the TetraEther indeX of 86 carbons (TEX86), a proxy that utilizes marine archaeal biomarkers. The Scotia Sea TEX86-based paleotemperature record will be compared to records of AIS variability, including ice rafted debris. Expedition 382 records will be compared to orbitally paced climatic time series and the benthic oxygen isotope record of global ice volume and bottom water temperature to determine if a correlation exists between upper ocean temperature, AIS retreat/advance, and orbital climate forcing. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This study will collect a novel dataset to determine how the West Antarctic Ice Sheet (WAIS) responded to a warmer climate during the last interglacial period (~125,000 years ago) by reconstructing the glacial history at the Mt. Waesche volcano. Reconstructing WAIS geometry when the ice sheet was smaller than present is difficult and data are lacking because the evidence lies beneath the present ice sheet. This study will drill through the ice sheet and recover bedrock that can be analyzed for its surface exposure history to help determine when the surface became overridden by the ice sheet. This study will provide constraints on the past maximum and minimum spatial extent of WAIS during the last glacial-interglacial cycle. Understanding the geometry of a reduced WAIS during intervals when the planet was warmer than present may provide a possible analogue for future environmental conditions given predicted temperature trends. A reduction of WAIS results in rising sea levels which threatens coastal communities across the globe. The data will help improve numerical ice sheet models to better predict WAIS response to current and future climate trends. The project supports a teacher educational workshop and the training of graduate and undergraduate students. The goal of this project is to obtain rock samples from beneath the WAIS through shallow (<80 m) drilling at Mt. Waesche, a volcano in Marie Byrd Land, near an ice dome of WAIS (2000 m elevation). The lithologies of lava flows exposed on the flank of the volcano are well-suited for cosmogenic 3He and 36Cl as well as 40Ar/39Ar measurements which will establish eruption and exposure age. Existing 40Ar/39Ar data indicate basaltic lava flows on the volcano flank as young as 350 ka. Thus, measured cosmogenic nuclides measured in rock cores from beneath the ice surface will be indicative of relatively recent exposure during periods of reduced ice elevation, most likely, during the last interglacial. The first field season is focused on identifying appropriate locations for drilling and a ground penetrating radar (GPR) survey of the subglacial topography <100m under the blue ice area. Mapping and dating the adjacent exposed lava flows will allow tracing of lava flows of known age and composition below the ice margin that will be targeted for drilling the following year. The second field season activities include drilling 8 boreholes (two transects) through blue ice with the Winkie drill near the ice margin to 80 m depth to obtain rock cores from the sub-ice lava flows. 3He exposure ages will constrain the duration and minimum extent of past surface lowering of the WAIS in Marie Byrd Land. Deeper GPR imaging (up to 700 m) will hope to reveal additional evidence of lava/ice interactions that would independently place constraints on lower ice levels during past eruptions. Results from this study will be compared with the modeled ice elevation histories at Mt. Waesche to validate ice sheet modeling efforts. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). Ice shelves play a critical role in restricting the seaward flow of grounded glacier ice by providing buttressing at their bases and sides. Processes that affect the long-term stability of ice shelves can therefore influence the future contribution of the Antarctic Ice Sheet to global sea-level rise. The Ross Ice Shelf is the largest ice shelf on Earth, and it buttresses massive areas of West and East Antarctica. Previous studies of modern ice velocity indicated that the Ross Ice Shelf’s mass loss is roughly balanced by its mass gain. However, more recent work that extends further back in time reveals the ice shelf is likely not in steady state, with possible long-term thinning since the late 1990s. Consequently, to accurately interpret modern-day ice-shelf changes, long-term observations are critical to evaluate how these recent variations fit into the historical context of ice-shelf variability. This project will examine more than four decades of historical and modern airborne radar sounding observations of the Ross Ice Shelf (spanning 1971 to 2017) to investigate ice-shelf changes on decadal timescales. The team will process, calibrate, and analyze radar data collected during 1971-79 field campaigns and compare them against modern observations collected between 2011-17. They will estimate basal melt rates by examining changes in ice-shelf thickness, and will determine other important metrics for melt, including ice-shelf roughness, englacial temperature, and marine-ice formation. The project will support the education of a Ph.D. student at each of the three participating institutions. In addition, the project will support the training of undergraduate and high-school researchers in radioglaciology and Antarctic sciences. The project will test the hypothesis that, over decadal timescales, the basal melt rates beneath the Ross Ice Shelf have been low, particularly under shallow ice drafts, leading to overall thickening and increased buttressing potential. The team aims to provide a direct estimate of basal melt rates based on changes in ice-shelf thickness that occurred between 1971 and 2017. This project will extend similar work completed at Thwaites Glacier and improve the calibration methods on the vertical scaling for fast-time and depth conversion. The work will also leverage the dense modern surveys to improve the geolocation of radar film collected on earlier field campaigns to produce a more precise comparison of local shelf thickness with the modern data. In addition, the team will conduct englacial attenuation analysis to calculate englacial temperature to infer the trends in local basal melting. They will also examine the radiometric and scatterometric character of bed echoes at the ice-ocean boundary to characterize changes in ice-shelf basal roughness, marine-ice formation related to local basal freezing, and structural damage from fracture processes. 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.
Nontechnical Description The Antarctic core collection, curated at Florida State University since 1963, is one of the world?s premier marine geology collections. Consisting of irreplaceable sediment cores, this archive has greatly advanced the understanding of the Earth system, past and present, and will remain critical to future studies of the Earth. Given Oregon State University?s (OSU) leadership in marine research and long track record providing state-of-the-art curatorial services through the OSU Marine and Geology Repository, this facility will provide world-class curatorial stewardship of the Antarctic core collection for decades to come. The Antarctic core collection will be co-located and co-managed with the current OSU collection in a single modern repository and analytical facility. The combined collection will contain more than 30 km of refrigerated sediment core from the world?s oceans and will be housed in a new 33,000 SFT facility purchased in 2009 by OSU and upgraded in 2016-17. The total refrigerated space can hold both collections comfortably and has at least five decades of expansion space. The co-location and co-management of these two collections, paired with a modern suite of analytical facilities, will lead to greater collaboration, cross-pollination of ideas, and availability of enhanced technical services and capabilities for a growing user group that increasingly relies on marine sediments. The facility will employ a comprehensive community interaction plan that takes advantage of the new OSU Marine and Geology Repository building with a 32-person seminar room, its large 1,044 square foot core lab, and ten adjoining analytical laboratories, which will provide scientific and experiential learning opportunities for students, the general public, and the Earth Sciences research community. The facility will organize small group meetings, sampling parties and summer schools that will complement ongoing support for teaching, training and learning through the use of the repository in graduate, undergraduate, and K-12 classes and Research Experience for Undergraduate programs. The repository is open to the general public for tours and presentations, and the data products derived from the facility will be disseminated via the repository website at http://osu-mgr.org/ and other national databases. Technical Description The Antarctic and the Southern Ocean National Collection of Rock and Sediment Cores currently housed at Florida State University will be relocated to Oregon State University (OSU) and housed along with the OSU Marine and Geology Repository. Oregon State University investigators will co-manage the Antarctic core collection and the Marine and Geology Repository as a single modern repository and analytical facility. The combined collection will be housed a new 33,000 square foot building with refrigerated space that can hold both collections with approximately five decades of expansion space. The co-location and co-management of these two collections offers unique curatorial synergies, cost savings, and improved capabilities to support both the research and educational needs of a wider marine and Antarctic communities. The facility will house a 32-person seminar room, a large 1,044 square foot core lab that allows layout, inspection and examination of cores, and adjoining analytical laboratories that will provide quantitative analysis as well as experiential learning opportunities for students.
Non-Technical Abstract: The Polar Rock Repository (PRR) at The Ohio State University provides a unique resource for researchers studying the polar regions by offering free access to geological samples and data. This project seeks support to continue expanding and managing the collection, which is vital for scientific studies and planning fieldwork in Antarctica. Over the next five years, the repository plans to add tens of thousands of new samples and images, making it easier for researchers to study polar geology without the high cost and environmental impact of traveling to remote Antarctic locations. The PRR also supports education and outreach by providing hands-on resources for schools, colleges, and the public, including a "Polar Rock Box" program that brings real Antarctic samples into classrooms. This work ensures the preservation of important scientific materials and makes them accessible to a broad community, advancing understanding of our planet’s polar regions. Technical Abstract: The Polar Rock Repository (PRR) at The Ohio State University serves as a critical resource for polar earth science research, offering no-cost loans of geological samples and comprehensive metadata to the scientific community. This proposal seeks funding to support the continued curation, expansion, and management of the PRR, alongside its educational and outreach initiatives. Over the next five years, the PRR anticipates acquiring approximately 15,000 new samples, including those from major drilling operations (RAID, Winkie drill cores) and polar cruises. The repository also aims to significantly grow its archives of images, petrographic thin sections, and mineral separates. By preserving these physical and digital assets in a discoverable online database, the PRR fosters transparency, reproducibility, and accessibility in polar research, fulfilling Antarctic data management mandates. The intellectual merit lies in enabling cutting-edge scientific analyses through freely available samples and metadata. Broader impacts include reduced environmental costs of Antarctic research, enhanced educational opportunities, and outreach to a diverse audience through initiatives like the "Polar Rock Box" program. 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.
Nontechnical Abstract Mount Erebus volcano on Ross Island, Antarctica, is the southernmost active volcano on the planet. It provides a natural laboratory to study a volcanic system that has been in a continuous state of activity with a persistent lava lake over at least the last 40 years. Worldwide only four other volcanoes with such long-lived lava lakes exist: Erta Ale, Ethiopia; Kilauea, Hawaii; Nyiragongo, Congo; and Ambrym, Vanuatu. These volcanoes are a rare anomaly that provide a window into the underlying magmatic system and behavior. Erebus is of particular interest as it cycles through phases of very explosive activity every 20 thousand years. This project will investigate interactions between the magmatic system, the rift it is located in, and the impact of the gravitational load the volcano imposes on the underlying crust and its own magmatic system. Possible interactions between these factors may explain the changes in activity. The project will analyze geophysical data that have been collected at Erebus over at least the last two decades. The results of this work will be available to the public and scientific community and inform geodynamic models in this region. The project funds an early-career scientist and a graduate student at New Mexico Tech and contributes to the development of the next generation of scientists. Technical Abstract The proposed work targets scientific questions recently formulated by the community during the 2016 NSF-sponsored Scientific Drivers and Future of Mount Erebus Volcano Observatory workshop. The location and geometry of the magmatic plumbing from vent to lower crust system remain poorly constrained, particularly below 1 km depth. The style and causes for changes in volcanic and magmatic activity over the short term (minutes to hours) and on the decadal scale remains enigmatic. Two decades of campaign and continuous GPS data on Ross Island will inform about the longer term dynamics of both, Ross Island growing within the Terror Rift, and Erebus? deeper magmatic system. This project will organize and analyze all existing GPS data for Ross Island, and interpret any anomalies in the resulting time series. These activities require organization, consistent processing and interpretation/modeling of the existing ~20 years of GPS data, which include campaign, continuous, and high-rate GPS observations. We will generate these position time series in a consistent local reference frame and make the results, including models of transient deformation available to the community. Volcanic, tectonic and isostatic adjustment related deformation will be modeled to place Erebus in a broad volcano-tectonic framework of West Antarctica. During the data analysis phase, the utility of existing GPS data for reflection studies of snow and sea-level dynamics will also be evaluated.
Part I: Non-technical description: Methane is one of the more effective atmospheric gases at retaining heat in the lower atmosphere and the earth’s crust contains large quantities of methane. Research that identifies the factors that control methane’s release into the atmosphere is critical to understanding and mitigating climate change. One of the most effective natural processes that inhibits the release of methane from aquatic habitats is a community of bacteria and Archaea (microbes) that use the chemical energy stored in methane, transforming methane into less-climate-sensitive compounds. The amount of methane that may be released in Antarctica is unknown, and it is unclear which microbes consume the methane before it is released from the ocean in Antarctica. This project will study one of the few methane seeps known in Antarctica to advance our understanding of which microbes inhibit the release of methane in marine environments. The research will also identify if methane is a source of energy for other Antarctic organisms. The researchers will analyze the microbial species associated with methane consumption over several years of field and laboratory research based at an Antarctic US station, McMurdo. This project clearly expands the fundamental knowledge of Antarctic systems, biota, and processes outlined as a goal in the Antarctic solicitation. This research communicates and produces educational material for K-12, college, and graduate students to inspire and inform the public about the role Antarctic ecosystems play in the global environment. This project also provides a young professor an opportunity to establish himself as an expert in the field of Antarctic microbial ecology to help solidify his academic career. Part II: Technical description: Microbes act as filter to methane release from the ocean into the atmosphere, where microbial chemosynthetic production harvests the chemical energy stored in this greenhouse gas. In spite of methane reservoirs in Antarctica being as large as Arctic permafrost, we know only a little about the taxa or dominant processes involved in methane consumption in Antarctica. The principal investigator will undertake a genomic and transcriptomic study of microbial communities developed and still developing after initiation of methane seepage in McMurdo Sound. An Antarctic methane seep was discovered at this location in 2012 after it began seeping in 2011. Five years after it began releasing methane, the methane-oxidizing microbial community was underdeveloped and methane was still escaping from the seafloor. This project will be essential in elucidating the response of microbial communities to methane release and identify how methane oxidation occurs within the constraints of the low polar temperatures. This investigation is based on 4 years of field sampling and will establish a time series of the development of cold seep microbial communities in Antarctica. A genome-to-ecosystem approach will establish how the Southern Ocean microbial community is adapted to prevent methane release into the ocean. As methane is an organic carbon source, results from this study will have implications for the Southern Ocean carbon cycle. Two graduate students will be trained and supported with undergraduates participating in laboratory activities. The researcher aims to educate, inspire and communicate about Antarctic methane seeps to a broad community. A mixed-media approach, with videos, art and education in schools will be supported in collaboration with a filmmaker, teachers and a visual artist. Students will be trained in filmmaking and K-12 students from under-represented communities will be introduced to Antarctic science through visual arts. 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.
Western Antarctica is one of the fastest warming locations on Earth. Its changing climate will lead to an increase in sea-level and will also alter regional water temperature and chemistry. These changes will directly alter the microbes that inhabit the ecosystem. Microbes are the smallest forms of life on Earth, but they are also the most abundant. They drive cycling of essential nutrients, such as carbon and nitrogen that are found in ocean sediments. In this way they form the foundation of the food chain that supports larger and more complex life. However, we do not know much about how different communities of microbes break down sediments in Antarctica and this will influence the chemistry of those waters. This research will determine how communities of microbes on the coastal shelf of Antarctica degrade complex organic sediments using genetic and chemical data. This data will identify the species in the community, what enzymes they are producing and what chemical reactions they are driving. This research will create broader impacts as the data will be used to create in-class activities that improve a student’s data analysis and critical thinking skills. The data will be used in graduate, undergraduate and K-12 classrooms. This research will provide genetic and enzymatic insight into how microbial communities in benthic sediments on the coastal shelf of Antarctica degrade complex organic matter. The current understanding of how benthic microbial communities respond to and then degrade complex organic matter in Antarctica is fragmented. Recent work suggests benthic microbial communities are shaped by organic matter availability. However, those studies were observational and did not directly examine community function. A preliminary study of metagenomic data from western Antarctic marine sediments, indicates a genetic potential for organic matter degradation but functional data was not been collected. Other studies have examined either enzyme activity or metagenomic potential, but few have been able to directly connect the two. To address this gap in knowledge, this study will utilize metagenomics and metatranscriptomics, coupled with microcosm experiments, enzyme assays, and geochemical data. It will examine Antarctic microbial communities from the Ross Sea, the Bransfield Strait and Weddell Sea to document how the relationship between a communities’ enzymatic activity and the genes used to degrade complex organic matter is related to sediment breakdown. The data will expand our current knowledge of microbial genetic potential and provide a solid understanding of enzyme function as it relates to degradation of complex organic matter in those marine sediments. It will thereby improve our understanding of temperature change on the chemistry of Antarctic seawater. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The emperor penguin is an iconic seabird that is found in colonies distributed around the entirety of the Antarctic coastline. Emperor penguins are an important indicator species for the health of the Southern Ocean because their reliance on sea ice for major parts of their life cycle means that their population can be influenced by changes in the extent and duration of sea ice around Antarctica. Although baseline data exists on emperor penguin distributions and overall population size, data on how population size varies at individual colonies is limited to only a few locations. Thus, knowledge about how changes in local or regional environmental conditions impacts local or global population status is poorly understood. By combining established methods in satellite remote sensing with ground and aerial surveys of several colonies across the continent, this project will generate population estimates for the 54 known emperor penguin colonies. Decadal scale population trend data will be combined with environmental variables (e.g., sea ice extent and duration among others) to reveal which conditions influence population fluctuations at regional and continental scales. The project will engage with international collaborators, train post-doctoral associates and future scientists, and develop citizen science and K-12 outreach programs. This project on emperor penguin populations will quantify penguin presence/absence, and colony size and trajectory, across the entire Antarctic continent using high-resolution satellite imagery. For a subset of the colonies, population estimates derived from high-resolution satellite images will be compared with those determined by aerial surveys. This validated information will be used to determine population estimates for all emperor penguin colonies through iterations of supervised classification and maximum likelihood calculations on the high-resolution imagery. The effect of spatial, geophysical, and environmental variables on population size and decadal-scale trends will be assessed using generalized linear models. This research will result in a first ever empirical result for emperor penguin population trends and habitat suitability, and will leverage currently-funded NSF infrastructure and hosting sites to publish results in near-real time to the public. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The near surface atmosphere over West Antarctica is one of the fastest warming locations on the planet. This atmospheric warming, along with oceanic forcing, is contributing to ice sheet melt and hence rising global sea levels. An observational campaign, focused on the atmospheric boundary layer over the West Antarctic ice sheet, is envisioned. A robust set of year-round, autonomous, atmospheric and surface measurements, will be made using an instrumented 30-m tall tower at the West Antarctic ice sheet divide field camp. An additional unmanned aerial system field campaign will be conducted during the second year of this project and will supplement the West Antarctic ice sheet tall tower observations by sampling the depths of the boundary layer. The broader subject of the Antarctic ABL clearly supports a range of research activities ranging from the physics of turbulent mixing, its parameterization and constraints on meteorological forecasts, and even climatological effects, such as surface mass and energy balances. With the coming of the Thwaites WAIS program, a suite of metrological observables would be a welcome addition to the joint NSF/NERC (UK) Thwaites field campaigns. The meteorologists of this proposal have pioneered 30-m tall tower (TT) and unmanned aerial system (UAS) development in the Antarctic, and are well positioned to successfully carry out and analyze this work. In turn, the potential for these observations to advance our understanding of how the atmosphere exchanges heat with the ice sheet is high. 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.
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.
Non-technical Abstract Around 252 million years ago, a major mass extinction wiped out over 90% of species on Earth. Coincident with this extinction, the Antarctic portion of the supercontinent of Pangea transitioned to a warmer climatic regime devoid of a permanent ice cap. Compared to lower latitudes, relatively little is known about the survivors of the extinction in Antarctica, although it has been hypothesized that the continents more polar location shielded it from the worst of the extinctions effects. As the result of a NSF-sponsored deep field camp in 2017/2018, a remarkable collection of vertebrate fossils was discovered in the rocks of the Shackleton Glacier region. This collection includes the best preserved and most complete materials of fossil amphibians ever recovered from Antarctica, including two previously undescribed species. This grant supports one postdoctoral researcher with expertise in fossil amphibians to describe and interpret the significance of these fossils, including their identification, relationships, and how they fit into the terrestrial ecosystem of Antarctica and other southern hemisphere terrestrial assemblages in light of the major reorganization of post-extinction environments. Historical collections of fossil amphibians will also be reviewed as part of this work. Undergraduate students at the University of Washington will be actively involved as part of this research and learn skills like hard tissue histology and CT data manipulation. Public engagement in Antarctic science will be accomplished at the University of Washington Burke Museum, which is the Washington State museum of natural history and culture. Specifically, a new exhibit on Antarctic amphibians will be developed as part of the paleontology gallery, which sees over 100,000 visitors per year. Technical Abstract This two-year project will examine the evolution of Triassic temnospondyls based on a remarkable collection of fossils recently recovered from the Shackleton Glacier region of Antarctica. Temnospondyls collected from the middle member of the Fremouw Formation are part of the first collection of identifiable tetrapod fossils from this stratigraphic interval. Thorough anatomical description and comparisons of these fossils will add new faunal information and also aid in determining if this horizon is Early or Middle Triassic in age. Exquisitely preserved temnospondyl material from the lower Fremouw Formation will permit more precise identification than previously possible and will provide insights into the earliest stages of their radiation in the extinction recovery interval. Overall, the Principal Investigator and Postdoctoral Researcher will spearhead an effort to revise the systematics of the Antarctic members of Temnospondyli and properly contextualize them in the framework of Triassic tetrapod evolution. The research team will also take advantage of the climate-sensitive nature of fossil amphibians to better understand patterns of seasonality at high-latitudes during the early Mesozoic by subjecting selected fossils to histological analysis. Preliminary data suggest that temnospondyls were exceptionally diverse and highly endemic immediately after the end-Permian extinction, when compared to their distribution before and after this interval. If confirmed, this macroevolutionary pattern could be used to predict the response of modern amphibians to future climate perturbations. Overall, this research will provide new insights into the vertebrate fauna of the Fremouw Formation, as well as shed light on the evolution of terrestrial ecosystems in southern Pangea in the wake of the Permian-Triassic mass extinction. As part of the broader impacts, the research team will help to develop an exhibit featuring some of the best preserved fossils from Antarctica to explain to the public how paleontologists use fossils and rocks to understand past climates like the Triassic 'hot-house' world that lacked permanent ice caps at the poles. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This project will develop a new ice-penetrating radar system that can simultaneously map glacier geometry and glacier flow along repeat profiles. Forecasting an ice-sheet’s contribution to sea level requires an estimate for the initial ice-sheet geometry and the parameters that govern ice flow and slip across bedrock. Existing ice-sheet models cannot independently determine this information from conventional observations of ice-surface velocities and glacier geometry. This introduces substantial uncertainty into simulations of past and future ice-sheet behavior. Thus, this new radar capability is conceived to provide the needed data to support higher-fidelity simulations of past and future ice-sheet behavior and more accurate projections of future sea level. The new radar system will integrate two existing radars (the multi-channel coherent radio-echo depth sounder and the accumulation radar) developed by the Center for the Remote Sensing of Ice Sheets, as well as adding new capabilities. An eight-element very high frequency (VHF; 140-215 MHz) array will have sufficient cross-track aperture to swath map internal layers and the ice-sheet base in three dimensions. A single ultra high frequency (UHF; 600-900 MHz) antenna will have the range and phase resolution to map internal layer displacement with 0.25-mm precision. The VHF array will create 3D mappings of layer geometry that enable measurements of vertical velocities by accounting for spatial offsets between repeat profiles and changing surface conditions. The vertical displacement measurement will then be made by determining the difference in radar phase response recorded by the UHF antenna for radar profiles collected at the same locations at different times. The UHF antenna will be dual-polarized and thus capable of isolating both components of complex internal reflections. This should enable inferences of ice crystal orientation fabric and widespread mapping of ice viscosity. Initial field testing of the radar will occur on the McMurdo Ice Shelf and then progress to Thwaites Glacier, Antarctica. The dual-band radar system technology and processing algorithms will be developed with versatile extensible hardware and user-friendly software so that this system will serve as a prototype for a future community radar system. 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.
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.
The ice of the polar ice sheets is among the purest substances on Earth, yet the small amount of impurities --such as acids-- are important to how the ice flows and what can be learned from ice cores about past climate. The goal of this project is to understand the role of such acids on the deformation of polycrystalline ice by comparing the deformation behavior of pure and sulfuric acid-doped samples. Sulfuric acid was chosen both because of its importance for interpreting past climate and because it can lead to water veins in ice at low temperatures. This work will focus on the location, movement, and impact of acids in polycrystalline ice that are more complex than in single crystals of ice. By deforming samples and performing microstructural characterization, the role of acids on deformation rate, grain evolution, and the movement of the acids themselves, will be assessed. The work will lead to the education of a Ph.D. student at Dartmouth College, introduce undergraduate students to research at both the University of Washington and Dartmouth College. Despite the ubiquitous use of the constitutive relation for ice commonly referred to as "Glen's Flow Law", significant uncertainty exists particularly with regard to the role of impurities and the development of oriented fabrics. The aim of this project is to improve the constitutive relationship for ice by performing deformation tests and microstructural characterization of pure and sulfuric acid-doped ice. The project will focus on sulfuric acid's impact on ice viscosity, fabric evolution, and diffusivity. Sulfuric acid can have both direct and indirect effects on the mechanical properties of polycrystalline ice. The direct effects change the dislocation velocity and/or density, and the indirect effects change the grain size and fabric. The complexity and interaction of these effects means that it is not possible to understand the effects of sulfuric acid by simply examining ice core specimens. In this project, the team will deform four types of ice: lab-grown ice samples doped with similar-to-natural concentrations of sulfuric acid, lab-grown high-purity ice, layered doped and pure ice, and natural ice from Antarctic ice cores. Deformation will be performed in both uniaxial compression and simple shear. The addition of simple shear tests is critical for relating the laboratory-observed deformation behavior to the behavior of polar ice sheets where the shear strain dominates ice motion in basal ice. After deformation to strains from 5 percent up to 25 percent, the microstructural development will be assessed with methods including a variety of scanning electron microscope techniques, Raman microscopy, synchrotron-based Nano-X-ray fluorescence, and ion chromatography. These analysis techniques will allow the determination of 1) the segregation and movement of impurities, 2) the rate of grain-boundary migration, 3) the number of recrystallized grains; and 4) the full orientation of the ice crystals. The results will enable both microstructural modeling of the effects of sulfuric acid and numerical modeling of diffusion in ice cores. The net result will be a better understanding of ice deformation that improves ice-core interpretation and ice-sheet modeling. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The cold, dry terrestrial environments of Antarctica are inhospitable for insects, and only three midge species make Antarctica home. Of these, Belgica antarctica is the only species found exclusively in Antarctica, and it has been a resident of Antarctica since the continent split from South America ~30 million years ago. Thus, this species is an excellent system to model the biological history of Antarctica throughout its repeated glaciation events and shifts in climate. This insect is also a classic example of extreme adaptation, and much previous work has focused on identifying the genetic and physiological mechanisms that allow this species to survive where no other insect is capable. However, it has been difficult to pinpoint the unique evolutionary adaptations that are required to survive in Antarctica due to a lack of information from closely related Antarctic and sub-Antarctic species. This project will compare adaptations, genome sequences, and population characteristics of four midge species that span an environmental gradient from sub-Antarctic to Antarctic habitats. In addition to B. antarctica, these species include two species that are strictly sub-Antarctic and a third that is native to the sub-Antarctic but has invaded parts of Antarctica. The researchers, comprised of scientists from the US, UK, Chile, and France, will sample insects from across their geographic range and measure their ability to tolerate environmental stressors (i.e., cold and desiccation), quantify molecular responses to stress, and compare the makeup of the genome and patterns of genetic diversity. This research will contribute to a greater understanding of adaptation to extremes, to an understanding of biodiversity on the planet and to understanding and predicting changes accompanying environmental change. The project will train two graduate students and two postdoctoral researchers, and a K-12 educator will be a member of the field team and will assist with fieldwork and facilitate outreach with schools in the US. The project includes partnership activities with several STEM education organizations to deliver educational content to K-12 and secondary students. This is a project that is jointly funded by the National Science Foundation's Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Each Agency funds the proportion of the budget and the investigators associated with its own country. UK participation in this project includes deploying scientists as part of the field team, supporting field and sampling logistics at remote Antarctic sites, and genome sequencing, annotation, and analyses. This project focuses on the key physiological adaptations and molecular processes that allow a select few insect species to survive in Antarctica. The focal species are all wingless with limited dispersal capacity, suggesting there is also significant potential to locally adapt to variable environmental conditions across the range of these species. The central hypothesis is that similar molecular mechanisms drive both population-level adaptation to local environmental conditions and macroevolutionary changes across species living in different environments. The specific aims of the project are to 1) Characterize conserved and species-specific adaptations to extreme environments through comparative physiology and transcriptomics, 2) Compare the genome sequences of these species to identify genetic signatures of extreme adaption, and 3) Investigate patterns of diversification and local adaptation across each species? range using population genomics. The project establishes an international collaboration of researchers from the US, UK, Chile, and France with shared interests and complementary expertise in the biology, genomics, and conservation of Antarctic arthropods. The Broader Impacts of the project include training students and partnering with the Living Arts and Science Center to design and implement educational content for K-12 students. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Glacial retreat in West Antarctica is correlated with ocean warming; however, less is known about the ocean's effect on East Antarctica's glaciers including Totten Glacier located on the Sabrina Coast. The retreat of Totten Glacier has global significance as the glacier drains a sector of the East Antarctic Ice Sheet that contains enough ice to raise global sea levels by as much as 3.5 meters. This study looks to determine the influence of ocean temperatures on East Antarctic glaciers, including Totten Glacier, over the last ~18,000 years by studying seafloor sediment around Antarctica. These sediments, or muds, include the remains of microscopic marine organisms as well as tiny particles originating from eroded Antarctic bedrock. These muds provide a record of past environmental changes including ocean temperatures and the advance and retreat of glaciers. Scientists use a variety of physical and chemical analyses to determine how long ago this mud was deposited, the temperature of the ocean at that location through time, and the relative location of glacial ice. In this project, researchers will refine and test new methods for measuring ocean temperature from the sediments to better understand the influence of ocean temperatures on East Antarctic glacier response. Results will be integrated into ice sheet and climate models to improve the accuracy of ice sheet modeling efforts and subsequent sea level predictions. Results from this project will be disseminated at scientific conferences, in the scientific literature, and more broadly to the general public via the St. Petersburg Science Festival and at the Oceanography Camp for Girls. The influence of ocean temperatures on East Antarctic glaciers is largely unknown. This research focuses on ice-proximal Antarctic margin paleoceanographic proxy calibration and validation, which will improve understanding of past ocean-ice sheet interactions on a variety of timescales. In this project, researchers from the University of South Florida will (1) further develop and refine two ocean temperature proxies, foraminifer Mg/Ca and TEX86, for use in ice-proximal Antarctic continental margin sediments and (2) investigate deglacial to present (~18-0 ka) ocean-ice interactions at the outlet of the climatically sensitive Aurora Subglacial Basin. The proposed research utilizes sediment trap, sediment core, and physical oceanographic data previously collected from the Sabrina Coast continental shelf during NSF-funded cruise NBP14-02. Studies of existing sediment cores will integrate multiple paleotemperature, meltwater/salinity, nutrient, bottom water oxygen, and sea ice proxies with geophysical and lithologic data to understand past regional ocean-ice interactions. While the recent international Antarctic research focus has been on understanding the drivers of West Antarctic Ice Sheet retreat, models suggest it would be imprudent to ignore the East Antarctic Ice Sheet, which is proving more sensitive to climate perturbations than previously realized. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This award is to support measurements of the 14-billion-year cosmic microwave background (CMB) light with the South Pole Telescope (SPT) to address some of the most basic and compelling questions in cosmology: What is the origin of the Universe? What is the Universe made of? What is the mass scale of the neutrinos? When did the first stars and galaxies form and how was the Universe reionized? What is the Dark Energy that is accelerating the expansion of the Universe? The SPT plays a unique role in the pursuit of these questions. Its siting is ideal for ultra-low-noise imaging surveys of the sky at the millimeter and sub-millimeter radio wavelengths. The SPT is supported by the NSF's Amundsen-Scott South Pole Station, which is the best operational site on Earth for mm-wave sky surveys. This unique geographical location allows SPT to obtain extremely sensitive 24/7 observations of targeted low Galactic foreground regions of the sky. The telescope's third-generation, SPT-3G receiver has 16,000 detectors configured for polarization-sensitive observations in three millimeter-wave bands. The proposed operation includes five years of sky surveys to obtain ultra-deep measurements of a 1500 square degree field and to produce and publicly archive essential data products from the survey. The telescope's CMB temperatures and polarization power spectrum will play a central role in probing the nature of current tensions among cosmological parameter estimations from different data sets and determining if their explanation requires physics beyond the current LCDM model. The data will help constraining the Dark Energy properties that affect the growth of large structures through both the CMB lensing and abundance of galaxy clusters. The proposed operations also support SPT's critical role in the Event Horizon Telescope (EHT), a global array of telescopes to image the event horizon around the black hole at the center of Milky Way Galaxy. This award addresses and advances the science objectives and goals of the NSF's "Windows on the Universe: The Era of Multi-Messenger Astrophysics" program. The proposed research activity will also contribute to the training of the next generation of scientists by integrating graduate and undergraduate education with the technology development, astronomical observations, and scientific analyses of SPT data. Research and education are integrated by bringing research activities into the undergraduate classroom and sharing of forefront research with non-scientists extending it beyond the university through a well-established educational network that reaches a wide audience at all levels of the educational continuum. Through museum partnerships and new media, the SPT outreach and educational efforts reach large numbers of individuals while personalizing the experience. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Ross Sea region of the Southern Ocean is experiencing growing sea ice cover in both extent and duration. These trends contrast those of the well-studied, western Antarctic Peninsula area, where sea ice has been disappearing. Unlike the latter, little is known about how expanding sea ice coverage might affect the regional Antarctic marine ecosystem. This project aims to better understand some of the potential effects of the changing ice conditions on the marine ecosystem using the widely-recognized indicator species - the Adélie Penguin. A four-year effort will build on previous results spanning 19 seasons at Ross Island to explore how successes or failures in each part of the penguin's annual cycle are effected by ice conditions and how these carry over to the next annual recruitment cycle, especially with respect to the penguin's condition upon arrival in the spring. Education and public outreach activities will continually be promoted through the PenguinCam and PenguinScience websites (sites with greater than 1 million hits a month) and "NestCheck" (a site that is logged-on by >300 classrooms annually that allows students to follow penguin families in their breeding efforts). To encourage students in pursuing educational and career pathways in the Science Technology Engineering and Math fields, the project will also provide stories from the field in a Penguin Journal, develop classroom-ready activities aligned with New Generation Science Standards, increase the availability of instructional presentations as powerpoint files and short webisodes. The project will provide additional outreach activities through local, state and national speaking engagements about penguins, Antarctic science and climate change. The annual outreach efforts are aimed at reaching over 15,000 students through the website, 300 teachers through presentations and workshops, and 500 persons in the general public. The project also will train four interns (undergraduate and graduate level), two post-doctoral researchers, and a science writer/photographer. The project will accomplish three major goals, all of which relate to how Adélie Penguins adapt to, or cope with environmental change. Specifically the project seeks to determine 1) how changing winter sea ice conditions in the Ross Sea region affect penguin migration, behavior and survival and alter the carry-over effects (COEs) to subsequent reproduction; 2) the interplay between extrinsic and intrinsic factors influencing COEs over multiple years of an individual?s lifetime; and 3) how local environmental change may affect population change via impacts to nesting habitat, interacting with individual quality and COEs. Retrospective analyses will be conducted using 19 years of colony based data and collect additional information on individually marked, known-age and known-history penguins, from new recruits to possibly senescent individuals. Four years of new information will be gained from efforts based at two colonies (Cape Royds and Crozier), using radio frequency identification tags to automatically collect data on breeding and foraging effort of marked, known-history birds to explore penguin response to resource availability within the colony as well as between colonies (mates, nesting material, habitat availability). Additional geolocation/time-depth recorders will be used to investigate travels and foraging during winter of these birds. The combined efforts will allow an assessment of the effects of penguin behavior/success in one season on its behavior in the next (e.g. how does winter behavior affect arrival time and body condition on subsequent breeding). It is at the individual level that penguins are responding successfully, or not, to ongoing marine habitat change in the Ross Sea region.
Coastal waters surrounding Antarctica represent some of the most biologically rich and most untouched ecosystems on Earth. In large part, this biological richness is concentrated within the numerous openings that riddle the expansive sea ice (these openings are known as polynyas) near the Antarctic continent. These polynyas represent regions of enhanced production known as hot-spots and support the highest animal densities in the Southern Ocean. Many of them are also located adjacent to floating extensions of the vast Antarctic Ice Sheet and receive a substantial amount of meltwater runoff each year during the summer. However, little is known about the specific processes that make these ecosystems so biologically productive. Of the 46 Antarctic coastal polynyas that are presently known, only a handful have been investigated in detail. This project will develop ecosystem models for the Ross Sea polynya, Amundsen polynya, and Pine Island polynya; three of the most productive Antarctic coastal polynyas. The primary goal is to use these models to better understand the fundamental physical, chemical, and biological interacting processes and differences in these processes that make these systems so biologically productive yet different in some respects (e.g. size and productivity) during the present day settings. Modeling efforts will also be extended to potentially assess how these ecosystems may have functioned in the past and how they might change in the future under different physical and chemical and climatic settings. The project will advance the education of underrepresented minorities through Stanford?s Summer Undergraduate Research in Geoscience and Engineering (SURGE) Program. SURGE will provide undergraduates the opportunity to gain mentored research experiences at Stanford University in engineering and the geosciences. Old Dominion University also will utilize an outreach programs for local public and private schools as well as an ongoing program supporting the Boy Scout Oceanography merit badge program to create outreach and education impacts. Polynyas (areas of open water surrounded by sea ice) are disproportionately productive regions of polar ecosystems, yet controls on their high rates of production are not well understood. This project will provide quantitative assessments of the physical and chemical processes that control phytoplankton abundance and productivity within polynyas, how these differ for different polynyas, and how polynyas may change in the future. Of particular interest are the interactions among processes within the polynyas and the summertime melting of nearby ice sheets, including the Thwaites and Pine Island glaciers. In this proposed study, we will develop a set of comprehensive, high resolution coupled physical-biological models and implement these for three major, but diverse, Antarctic polynyas. These polynyas, the Ross Sea polynya, the Amundsen polynya, and Pine Island polynya, account for >50% of the total Antarctic polynya production. The research questions to be addressed are: 1) What environmental factors exert the greatest control of primary production in polynyas around Antarctica? 2) What are the controlling physics that leads to the heterogeneity of dissolved iron (dFe) supply to the euphotic zone in polynyas around the Antarctic continental shelf? What effect does this have on local rates of primary production? 3) What are the likely changes in the supply of dFe to the euphotic zone in the next several decades due to climate-induced changes in the physics (winds, sea-ice, ice shelf basal melt, cross-shelf exchange, stratification and vertical mixing) and how will this affect primary productivity around the continent? The Ross Sea, Amundsen, and Pine Island polynyas are some of the best-sampled polynyas in Antarctica, facilitating model parameterization and validation. Furthermore, these polynyas differ widely in their size, location, sea ice dynamics, relationship to melting ice shelves, and distance from the continental shelf break, making them ideal case studies. For comparison, the western Antarctic Peninsula (wAP), a productive continental shelf where polynyas are a relatively minor contributor to biological production, will also be modeled. Investigating specific processes within different types Antarctic coastal waters will provide a better understand of how these important biological oases function and how they might change under different environmental conditions.
This award funds the continued management and operations (M&O) of the IceCube Neutrino Observatory (ICNO) located at the South Pole Station. The core team of researchers and engineers maintain the existing ICNO infrastructure at the South Pole and home institution, guaranteeing an uninterrupted stream of scientifically unique, high-quality data. The M&O activities are built upon eight highly successful years of managing the overall ICNO operations after the start of science operations in 2008. Construction of ICNO was supported by NSF's Major Research Equipment and Facilities Construction (MREFC) account and was completed on schedule and within budget in 2010. Effective coordination of efforts by the core M&O personnel and efforts by personnel within the IceCube Collaboration has yielded significant increases in the performance of this cubic-kilometer detector over time. The scientific output from the IceCube Collaboration during the past five years has been outstanding. The broader impacts of the ICNO/M&O activities are strong, involving postdoctoral, graduate, and (in some cases) undergraduate students in the day-today operation & calibration of the neutrino detector. The extraordinary physics results recently produced by ICNO and its extraordinary location at South Pole have a high potential to excite the imagination of high school children and the public in general at a national and international level. The current ICNO/M&O effort produces better energy and angular resolution information about detected neutrino events, has more efficient data filters and more accurate detector simulations, and enables continuous software development for systems that are needed to acquire and analyze data. This has produced data acquisition and data management systems with high robustness, traceability, and maintainability. The current ICNO/M&O effort includes: (1) resources for both distributed and centrally managed activities, and (2) additional accountability mechanisms for "in-kind" and institutional contributions. Both are necessary to ensure that the detector maintains its capability to produce quality scientific data at the level required to achieve the detector's scientific discovery objectives. Recent ICNO discoveries of cosmic high-energy neutrinos (some reaching energies close to and over 2.5 PeV) and oscillating atmospheric neutrinos in a previously unexplored energy range from 10 to 60 GeV became possible because of the "state-of-the-art" detector configuration, excellently supported infrastructure, and cutting-edge science analyses. The ICNO has set limits on Dark Matter annihilations, made precision measurements of the angular distribution of cosmic ray muons, and characterized in detail physical properties of the Antarctic 2.5-km thick ice sheet at South Pole. The discovery of high-energy cosmic neutrinos by IceCube with a flux at the level anticipated for those associated with high-energy gamma- and cosmic-ray accelerators brightens the prospect for identifying the sources of the highest energy particles.
This project evaluates the role that water and rock/ice properties at the base of a fast moving glacier, or ice stream, play in controlling its motion. In Antarctica, where surface melting is limited, the speed of ice flow through the grounding zone (where ice on land detaches, and begins to float on ocean water) controls the rate at which glaciers contribute to sea level rise. The velocity of the ice stream is strongly dependent on resistance from the bed, so understanding the processes that control resistance to flow is critical in predicting ice sheet mass balance. In fact, the Intergovernmental Panel on Climate Change (IPCC) recognized this and stated in their 4th assessment report that reliable predictions of future global sea-level rise require improved understanding of ice sheet dynamics, which include basal controls on fast ice motion. Drilling to obtain direct observations of basal properties over substantial regions is prohibitively expensive. This project uses passive source seismology to "listen to" and analyze sounds generated by water flow and/or sticky spots at the ice/bed interface to evaluate the role that basal shear stress plays in ice flow dynamics. Because polar science is captivating to both scientists and the general public, it serves as an excellent topic to engage students at all levels with important scientific concepts and processes. In conjunction with this research, polar science educational materials will be developed to be used by students spanning middle school through the University level. Starting in summer 2015, a new polar science class for high school students in the California State Summer School for Mathematics and Science (COSMOS) will be offered at the University of California-Santa Cruz. This curriculum will be shared with the MESA Schools Program, a Santa Cruz and Monterey County organization that runs after-school science clubs led by teachers at several local middle and high schools with largely minority and underprivileged populations. This proposal extends the period of borehole and surface geophysical monitoring of the Whillians Ice Stream (WIS) established under a previous award for an additional 2 years. Data from the WIS network demonstrated that basal heterogeneity, revealed by microseismicity, shows variation over scales of 100's of meters. An extended observation period will allow detailed seismic characterization of ice sheet bed properties over a crucial length scale comparable to the local ice thickness. Due to the fast ice velocity (>300 m/year), a single instrumented location will move approximately 1 km during the extended 3 year operational period, allowing continuous monitoring of seismic emissions as the ice travels over sticky spots and other features in the bed (e.g., patches of till or subglacial water bodies). Observations over ~1km length scales will help to bridge a crucial gap in current observations of basal conditions between extremely local observations made in boreholes and remote observations of basal shear stress inferred from inversions of ice surface velocity data.
This project will acquire measurements of the concentration of beryllium-10 (10Be) from an ice core from the South Pole, Antarctica. An isotope of the element beryllium, 10Be, is produced in the atmosphere by high-energy protons (cosmic rays) that enter Earth's atmosphere from space. It is removed from the atmosphere by settling or by scavenging by rain or snowfall. Hence, concentrations of 10Be in snow at the South Pole reflect the production rate of 10Be in the atmosphere. Because the rate of production of 10Be over Antarctica depends primarily on the strength of the Sun's magnetic field, measurements of 10Be in the South Pole ice core will provide a record of changes in solar activity. The South Pole ice core will reach an age of 40,000 years at the bottom. The project will result in measurements of 10Be at annual resolution for the last 100 years and selected periods in the more distant past, such as the Maunder Minimum, a period during the late 17th century during which no sunspots were observed, or the last glacial cold period, about 20,000 years ago. A climate model that can simulate the production of 10Be in the atmosphere, it's transport through the atmosphere, and its deposition at the snow surface in Antarctica will be used to aid in using the 10Be data to determine past changes in solar activity from decadal to millennial scale, and in turn to evaluate the role of the Sun in Earth?s climate from a new perspective. The production of 10Be in Earth's atmosphere results from the spallation of oxygen and nitrogen in the atmosphere by cosmic rays. Cosmic ray variations in the high latitudes are primarily modulated by solar variability. Time-series records of 10Be from ice cores are therefore important for deriving variations in solar activity through time, which is fundamental to understanding climate variability. Deposition of 10Be to the ice surface is also influenced by variability in atmospheric circulation and deposition processes, and South Pole is the best available location for minimizing the influence of variable atmospheric circulation on 10Be deposition. To date, only one record of 10Be exists from South Pole; that record is widely used in solar forcing estimates used in climate models, but covers only the last millennium and ends in CE 1982. We will obtain 10Be concentration measurements in a 1500-m, 40000-year long ice core from the South Pole. This will extend the existing record both further back in time and forward to the present, providing overlap with the modern instrumental record of solar and climate variability. High resolution (annual to biannual) measurements will be made in targeted areas of interest, including the last 100 years, the Maunder Minimum (CE 1650-1715), and the last glacial maximum. The novel data will be used in conjunction with climate model experiments that incorporate 10Be production, transport, and deposition physics. Together, data and modeling will create an updated record of atmospheric 10Be production and hence of solar activity.
This award supports a project to find and date geologic evidence of past ice-marginal positions in the Pensacola Mountains, which border the Foundation Ice Stream at the head of the Weddell Sea embayment. The project will involve glacial geologic mapping and cosmogenic-nuclide surface exposure dating of glacially transported erratics. An ice-flow model will be used to link our exposure-dating results together in a glaciologically consistent way, and to relate them to regional LGM to Holocene elevation changes. A secondary focus of the project seeks to improve the effectiveness of exposure-dating methods in understanding ice sheet change. Changes in the location of the ice margin, and thus the exposure ages that record these changes, are controlled not only by regional ice sheet mass balance, but also by local effects on snow- and icefields immediately adjacent to the exposure-dating sites. This part of the project will combine glaciological observations near the present ice margin with targeted exposure- age sampling in an effort to better understand the processes controlling the ice margin location, and improve the interpretation of very recent exposure-age data as a record of latest Holocene to present ice sheet changes. The intellectual merit of the project is that it will provide direct geologic evidence of LGM-to-Holocene ice volume change in a region of Antarctica where no such evidence now exists. The broader impacts of the work involve both gathering information needed for accurate understanding of past and present global sea level change. Secondly, this project will help to develop and maintain the human and intellectual resources necessary for continued excellence in polar research and global change education, by linking experienced Antarctic researchers with early career scientists who seek to develop their expertise in both research and education. In addition, it brings together two early career scientists whose careers are focused at opposite ends of the research-education spectrum, thus facilitating better integration of research and education both in the careers of these scientists and in the outcome of this project. This award has field work in Antarctica.
Notothenioid fishes live in the world's coldest marine waters surrounding Antarctica and have evolved strategies to avoid freezing. Past studies have shown that most Antarctic notothenioids produce special antifreeze proteins that prevent the growth of ice crystals that enter the body. While these proteins help prevent individuals from being killed by growing ice crystals, it is unclear how these fish avoid the accumulation of these small ice crystals inside their tissues over time. This project will observe how ice crystal accumulation relates to the harshness of the fish's habitat and the fish's behavior within different habitats of McMurdo Sound, Antarctica. The researchers will collect fishes and ocean observations at different field sites that cover a range of habitat severity in terms of temperature and iciness. Researchers will install an underwater ocean observatory near McMurdo Station which will include a HD video camera and hydrophone. The observatory will allow continuous monitoring of ocean conditions and fish behavior that will help explain the conditions and behaviors that contribute to the acquisition and accrual of ice inside the body. Acoustic and video data from the observatory will be available to other scientists and to the public. The project will advance understanding of the many challenges life faces in extreme cold environments. This work continues a line of inquiry that has resulted in the discovery of potential medical and food preservation applications. Hundreds of antifreeze protein (AFP) structure-function studies have been conducted in the laboratory, providing a basic physical understanding of the AFP-ice interaction. How AFPs function within fishes and their range of environments, however, is far from clear. This project will provide an understanding of notothenioid's freezing avoidance mechanisms, and strategies by quantifying the acquisition, accumulation, and loss of internal ice crystals. Specifically, the goal is to determine if and how habitat severity (as defined by iciness, seawater temperature, and prevalence of supercooled water) and fish behavior influence the abundance of ice crystals in their tissues. Four locations in the McMurdo Sound with different levels of habitat severity will be sampled for oceanographic conditions and ice crystal count within fish tissues. Researchers will use a new technique to count the number of splenic ice crystals, expanding on and simplifying previous methods. Environmental data loggers will be deployed for the duration of the project at the four sites to provide context and real-time assessment of environmental conditions. An oceanographic observatory near McMurdo Station will provide year-round, real-time and archival records of oceanographic conditions, in situ video observations of anchor ice growth and ice-organism interactions, hydroacoustic recordings, and serve as proof-of concept for expanding scientific infrastructure in McMurdo Sound related to monitoring of supercooled waters and oceanographic information.
The Siple Coast in West Antarctica has undergone significant glacier changes over the last millenium. Several ice streams--rapidly moving streams of ice bordered by slow-moving ice--exist in this region that feeds into the Ross Ice Shelf. A long-term slowdown of Whillans Ice Stream appears to be occurring, and this is affecting the zone between the Whillans and Mercer Ice Streams. However, the consistency of this slowdown and resulting changes to the shear margin between the two ice streams are unknown. The goal of this project is to quantify the observed changes over the past decade and understand the dynamic processes that cause them. A collateral benefit of and driver for this as a RAPID project is to test a method for assessing where crevassing will develop in this zone of steep velocity gradients. Such a method may benefit not only near-term field-project planning in the 2018-19 field season, but also planning for future fieldwork and traverses. The team will use remote sensing feature-tracking techniques to determine transient velocity patterns and shifts in the shear-zone location over the last 10-plus years. This velocity time series will be incorporated into a large-scale ice-sheet model to estimate ice-sheet susceptibility to changing boundary conditions over the next century based on likely regional ice-flux scenarios. This approach is an extension of recent work conducted by the team that shows promise for predicting areas of changing high strain rates indicative of an active glacier shear margin. The ultimate objectives are to characterize the flow field of merging ice streams over time and investigate lateral boundary migration. This will provide a better understanding of shear-margin control on ice-shelf and up-glacier stability. 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.
Nontechnical description of proposed research: This project will apply cutting-edge seismic imaging methods to existing seismic data to study the three-dimensional structure of the Earth beneath the ice-covered Antarctic continent. The study will improve understanding of Earth structure and hotspots and geologically recent and ancient rift systems. The results will be useful for models of ice movement and bedrock elevation changes due to variation in ice sheet thickness. The results will also help guide future seismic data collection. The researchers will transfer existing software from the high-performance computers at The University of Rhode Island to the Alabama supercomputer facilities. The project will also broaden public understanding of scientific research in Antarctica by engaging with the students and teachers in Socorro County, New Mexico to discuss career opportunities in science, technology, engineering, and mathematics (STEM), the Earth Sciences, and the importance of computers in scientific research. Project personnel from Alabama will visit Socorro and share research with students at New Mexico Tech and at the Socorro High School. The project will also train undergraduate and graduate students in the expanding field of computational seismology, by applying these approaches to study Antarctic geology. Technical description of proposed research: The project seeks to better resolve the three-dimensional Antarctic mantle structure and viscosity and to identify locations of ancient rifts within the stable East Antarctic lithosphere. To accomplish this, the researchers will utilize full-waveform tomographic inversion techniques that combine long-period ambient noise data with earthquake constraints to more accurately resolve structure than traditional tomographic approaches. The proposed research will be completed using the Alabama supercomputer facilities and the programs and methodology developed at The University of Rhode Island. The new tomographic results will be useful in assessing lithospheric structure beneath Dronning Maud Land as well as the Wilkes and Aurora Subglacial Basins in East Antarctica, where previous rifting episodes and mid-lithospheric discontinuities will be explored. In West Antarctica, the work will elucidate the easternmost extent of the West Antarctic Rift System as well as rifted structure and possible compositional variations within the Weddell Sea. The accuracy of existing Antarctic seismic models will be quantified through model validation approaches. The researchers will highlight regions of Antarctica where tomographic resolution is still lacking and where future deployments would improve resolution.
Baker/1141411 This award supports a project to undertake a systematic examination of the effects of soluble impurities, particularly sulfuric acid, on the creep of polycrystalline ice as function of temperature, strain rate and impurity concentration. The working hypothesis is that soluble impurities will increase the flow rate of polycrystalline ice compared to high-purity ice, that this effect will be temperature dependent and that the impurities by affecting the re-crystallization and grain growth will change the fabric of the ice. Both H2SO4-doped and high-purity poly-crystalline ice will be produced by freezing sheets of ice, breaking them up, sieving the ice particles and then sintering them in a mold into fine-grained cylindrical specimens with at least ten grains across their diameter. The resulting microstructures (dislocation structure, grain size and shape, grain boundary character and micro-structural location of the acid) will be characterized using a variety of techniques including: optical microscopy, scanning electron microscopy, including secondary electron imaging, electron backscattered patterns, energy dispersive X-ray spectroscopy, electron channeling contrast imaging, and X-ray topography. The creep of both the H2SO4-doped and the high-purity polycrystalline ice will be undertaken at a range of temperatures and stresses. The ice?s response to the creep deformation (grain boundary sliding, dislocation motion, re-crystallization, grain boundary migration, impurity redistribution) will be studied using a combination of methods. The creep behavior will be modeled and related to the microstructure. Of particular interest is how impurities affect the activation energy for creep. The intellectual merit of the work is that it will lead to a better understanding of glacier ice and will enable glaciologists to model the influence of impurities on the flow and fabric development in polycrystalline ice. The broader impacts of the project include the knowledge that will be gained of the effects of impurities on the flow of ice which will allow paleoclimatologists to better interpret ice core data and will allow scientists developing predictive models to better address the flow of ice sheets under various climate change scenarios. The project will also lead to the education and training of a Ph.D. student, several undergraduates and some high school students. Results from the research will be published in refereed journals. Several undergraduates, typically two per year, will also perform the work. Dartmouth aggressively courts minority students at all degree levels, and we will seek women or minority group undergraduates for this project. The undergraduates will be supported by Dartmouth?s nationally-honored Women In Science Project or by REU funding. The undergraduates? research will integrate closely with the Ph.D. student?s studies. Hanover High School students will also be involved in the project and develop an educational kit to introduce students to the properties of ice. Results from the research will be published in refereed journals and presented at conferences.
Scientists established more than 30 years ago that the climate-related variability of carbon dioxide levels in the atmosphere over Earth's ice-age cycles was regulated by the ocean. Hypotheses to explain how the ocean regulates atmospheric carbon dioxide have long been debated, but they have proven to be difficult to test. Work proposed here will test one leading hypothesis, specifically that the ocean experienced greater density stratification during the ice ages. That is, with greater stratification during the ice ages and slower replacement of deep water by cold dense water formed near the poles, the deep ocean would have held more carbon dioxide, which is produced by biological respiration of the organic carbon that constantly rains to the abyss in the form of dead organisms and organic debris that sink from the sunlit surface ocean. To test this hypothesis, the degree of ocean stratification during the last ice age and the rate of deep-water replacement will be constrained by comparing the radiocarbon ages of organisms that grew in the surface ocean and at the sea floor within a critical region around Antarctica, where most of the replacement of deep waters occurs. Completing this work will contribute toward improved models of future climate change. Climate scientists rely on models to estimate the amount of fossil fuel carbon dioxide that will be absorbed by the ocean in the future. Currently the ocean absorbs about 25% of the carbon dioxide produced by burning fossil fuels. Most of this carbon is absorbed in the Southern Ocean (the region around Antarctica). How this will change in the future is poorly known. Models have difficulty representing physical conditions in the Southern Ocean accurately, thereby adding substantial uncertainty to projections of future ocean uptake of carbon dioxide. Results of the proposed study will provide a benchmark to test the ability of models to simulate ocean processes under climate conditions distinctly different from those that occur today, ultimately leading to improvement of the models and to more reliable projections of future absorption of carbon dioxide by the ocean. The proposed work will add a research component to an existing scientific expedition to the Southern Ocean, in the region between the Ross Sea and New Zealand, that will collect sediment cores at three to five locations down the northern flank of the Pacific-Antarctic Ridge at approximately 170°W. The goal is to collect sediments at each location deposited since early in the peak of the last ice age. This region is unusual in the Southern Ocean in that sediments deposited during the last ice age contain foraminifera, tiny organisms with calcium carbonate shells, in much greater abundance than in other regions of the Southern Ocean. Foraminifera are widely used as an archive of several geochemical tracers of past ocean conditions. In the proposed work the radiocarbon age of foraminifera that inhabited the surface ocean will be compared with the age of contemporary specimens that grew on the seabed. The difference in age between surface and deep-swelling organisms will be used to discriminate between two proposed mechanisms of deep water renewal during the ice age: formation in coastal polynyas around the edge of Antarctica, much as occurs today, versus formation by open-ocean convection in deep-water regions far from the continent. If the latter mechanism prevails, then it is expected that surface and deep-dwelling foraminifera will exhibit similar radiocarbon ages. In the case of dominance of deep-water formation in coastal polynyas, one expects to find very different radiocarbon ages in the two populations of foraminifera. In the extreme case of greater ocean stratification during the last ice age, one even expects the surface dwellers to appear to be older than contemporary bottom dwellers because the targeted core sites lie directly under the region where the oldest deep waters return to the surface following their long circuitous transit through the deep ocean. The primary objective of the proposed work is to reconstruct the water mass age structure of the Southern Ocean during the last ice age, which, in turn, is a primary factor that controls the amount of carbon dioxide stored in the deep sea. In addition, the presence of foraminifera in the cores to be recovered provides a valuable resource for many other paleoceanographic applications, such as: 1) the application of nitrogen isotopes to constrain the level of nutrient utilization in the Southern Ocean and, thus, the efficiency of the ocean?s biological pump, 2) the application of neodymium isotopes to constrain the transport history of deep water masses, 3) the application of boron isotopes and boron/calcium ratios to constrain the pH and inorganic carbon system parameters of ice-age seawater, and 4) the exploitation of metal/calcium ratios in foraminifera to reconstruct the temperature (Mg/Ca) and nutrient content (Cd/Ca) of deep waters during the last ice age at a location near their source near Antarcitca.
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.
Abstract for the general public: The margins of the Antarctic ice sheet have advanced and retreated repeatedly over the past few million years. Melting ice from the last retreat, from 19,000 to 9,000 years ago, raised sea levels by 8 meters or more, but the extents of previous retreats are less well known. The main goal of this project is to understand how Antarctic ice retreats: fast or slow, stepped or steady, and which parts of the ice sheet are most prone to retreat. Antarctica loses ice by two main processes: melting of the underside of floating ice shelves and calving of icebergs. Icebergs themselves are ephemeral, but they carry mineral grains and rock fragments that have been scoured from Antarctic bedrock. As the icebergs drift and melt, this 'iceberg-rafted debris' falls to the sea-bed and is steadily buried in marine sediments to form a record of iceberg activity and ice sheet retreat. The investigators will read this record of iceberg-rafted debris to find when and where Antarctic ice destabilized in the past. This information can help to predict how Antarctic ice will behave in a warming climate. The study area is the Weddell Sea embayment, in the Atlantic sector of Antarctica. Principal sources of icebergs are the nearby Antarctic Peninsula and Weddell Sea embayment, where ice streams drain about a quarter of Antarctic ice. The provenance of the iceberg-rafted debris (IRD), and the icebergs that carried it, will be found by matching the geochemical fingerprint (such as characteristic argon isotope ages) of individual mineral grains in the IRD to that of the corresponding source area. In more detail, the project will: 1. Define the geochemical fingerprints of the source areas of the glacially-eroded material using samples from each major ice stream entering the Weddell Sea. Existing data indicates that the hinterland of the Weddell embayment is made up of geochemically distinguishable source areas, making it possible to apply geochemical provenance techniques to determine the origin of Antarctica icebergs. Few samples of onshore tills are available from this area, so this project includes fieldwork to collect till samples to characterize detritus supplied by the Recovery and Foundation ice streams. 2. Document the stratigraphic changes in provenance of iceberg-rafted debris (IRD) and glacially-eroded material in two deep water sediment cores in the NW Weddell Sea. Icebergs calved from ice streams in the embayment are carried by the Weddell Gyre and deposit IRD as they pass over the core sites. The provenance information identifies which groups of ice streams were actively eroding and exporting detritus to the ocean (via iceberg rafting and bottom currents), and the stratigraphy of the cores shows the relative sequence of ice stream activity through time. A further dimension is added by determining the time lag between fine sediment erosion and deposition, using a new method of uranium-series isotope measurements in fine grained material. Technical abstract: The behavior of the Antarctic ice sheets and ice streams is a critical topic for climate change and future sea level rise. The goal of this proposal is to constrain ice sheet response to changing climate in the Weddell Sea during the three most recent glacial terminations, as analogues for potential future warming. The project will also examine possible contributions to Meltwater Pulse 1A, and test the relative stability of the ice streams draining East and West Antarctica. Much of the West Antarctic ice may have melted during the Eemian (130 to 114 Ka), so it may be an analogue for predicting future ice drawdown over the coming centuries. Geochemical provenance fingerprinting of glacially eroded detritus provides a novel way to reconstruct the location and relative timing of glacial retreat during these terminations in the Weddell Sea embayment. The two major objectives of the project are to: 1. Define the provenance source areas by characterizing Ar, U-Pb, and Nd isotopic signatures, and heavy mineral and Fe-Ti oxide compositions of detrital minerals from each major ice stream entering the Weddell Sea, using onshore tills and existing sediment cores from the Ronne and Filchner Ice Shelves. Pilot data demonstrate that detritus originating from the east and west sides of the Weddell Sea embayment can be clearly distinguished, and published data indicates that the hinterland of the embayment is made up of geochemically distinguishable source areas. Few samples of onshore tills are available from this area, so this project includes fieldwork to collect till to characterize detritus supplied by the Recovery and Foundation ice streams. 2. Document the stratigraphic changes in provenance of iceberg-rafted debris (IRD) and glacially-eroded material in two deep water sediment cores in the NW Weddell Sea. Icebergs calved from ice streams in the embayment are carried by the Weddell Gyre and deposit IRD as they pass over the core sites. The provenance information will identify which ice streams were actively eroding and exporting detritus to the ocean (via iceberg rafting and bottom currents). The stratigraphy of the cores will show the relative sequence of ice stream activity through time. A further time dimension is added by determining the time lag between fine sediment erosion and deposition, using U-series comminution ages.
Tremblay, Marissa; Granger, Darryl; Balco, Gregory; Lamp, Jennifer
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. ______________________________________________________________________________________________________________ Part I: Nontechnical Description Scientists study the Earth's past climate in order to understand how the climate will respond to ongoing global change in the future. One of the best analogs for future climate might the period that occurred approximately 3 million years ago, during an interval known as the mid-Pliocene Warm Period. During this period, the concentration of carbon dioxide in the atmosphere was similar to today's and sea level was 15 or more meters higher, due primarily to warming and consequent ice sheet melting in polar regions. However, the temperatures in polar regions during the mid-Pliocene Warm Period are not well determined, in part because we do not have records like ice cores that extend this far back in time. This project will provide constraints on surface temperatures in Antarctica during the mid-Pliocene Warm Period using a new type of climate substitute, known as cosmogenic noble gas paleothermometry. This project focuses on an area of Antarctica called the McMurdo Dry Valleys. In this area, climate models suggest that temperatures were more than 10 C warmer during the mid-Pliocene than they are today, but indirect geologic observations suggest that temperatures may have been similar to today. The McMurdo Dry Valleys are also a place where rocks have been exposed to Earth surface conditions for several million years, and where this new climate substitute can be readily applied. The team will reconstruct temperatures in the McMurdo Dry Valleys during the mid-Pliocene Warm Period in order to resolve the discrepancy between models and indirect geologic observations and provide much-needed constraints on the sensitivity of Antarctic ice sheets to warming temperatures. The temperature reconstructions generated in this project will have scientific impact in multiple disciplines, including climate science, glaciology, geomorphology, and planetary science. In addition, the project will (1) broaden the participation of underrepresented groups by supporting two early-career female principal investigators, (2) build STEM talent through the education and training of a graduate student, (3) enhance infrastructure for research via publication of a publicly-accessible, open-source code library, and (4) be broadly disseminated via social media, blog posts, publications, and conference presentations. Part II: Technical Description The mid-Pliocene Warm Period (3-3.3 million years ago) is the most recent interval of the geologic past when atmospheric CO2 concentrations exceeded 400 ppm and is widely considered an analog for how Earth’s climate system will respond to current global change. Climate models predict polar amplification - the occurrence of larger changes in temperatures at high latitudes than the global average due to a radiative forcing - both during the mid-Pliocene Warm Period and due to current climate warming. However, the predicted magnitude of polar amplification is highly uncertain in both cases. The magnitude of polar amplification has important implications for the sensitivity of ice sheets to warming and the contribution of ice sheet melting to sea level change. Proxy-based constraints on polar surface air temperatures during the mid-Pliocene Warm Period are sparse to non-existent. In Antarctica, there is only indirect evidence for the magnitude of warming during this time. This project will provide constraints on surface temperatures in the McMurdo Dry Valleys of Antarctica during the mid-Pliocene Warm Period using a newly developed technique called cosmogenic noble gas (CNG) paleothermometry. CNG paleothermometry utilizes the diffusive behavior of cosmogenic 3He in quartz to quantify the temperatures rocks experience while exposed to cosmic-ray particles within a few meters of the Earth’s surface. The very low erosion rates and subzero temperatures characterizing the McMurdo Dry Valleys make this region uniquely suited for the application of CNG paleothermometry for addressing the question: what temperatures characterized the McMurdo Dry Valleys during the mid-Pliocene Warm Period? To address this question, the team will collect bedrock samples at several locations in the McMurdo Dry Valleys where erosion rates are known to be low enough that cosmic ray exposure extends into the mid-Pliocene or earlier. They will pair cosmogenic 3He measurements, which will record the thermal histories of our samples, with measurements of cosmogenic 10Be, 26Al, and 21Ne, which record samples exposure and erosion histories. We will also make in situ measurements of rock and air temperatures at sample sites in order to quantify the effect of radiative heating and develop a statistical relationship between rock and air temperatures, as well as conduct diffusion experiments to quantify the kinetics of 3He diffusion specific to each sample. This suite of observations will be used to model permissible thermal histories and place constraints on temperatures during the mid-Pliocene Warm Period interval of cosmic-ray exposure. 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.
Non-technical description: East Antarctica holds a vast, ancient ice sheet. The bedrock hidden beneath this ice sheet may provide clues to how today's continents formed, while the ice itself contains records of Earth's atmosphere from distant eras. New drilling technologies are now available to allow for direct sampling of these materials from more than two kilometers below the ice surface. However, getting this material will require knowing where to look. The Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP) project will use internationally collected airborne survey data to search East Antarctica near the South Pole for key locations that will provide insight into Antarctica's geology and for locating the oldest intact ice on Earth. Ultimately, scientists are interested in obtaining samples of the oldest ice to address fundamental questions about the causes of changes in the timing of ice-age conditions from 40,000 to 100,000 year cycles. SPICECAP data analysis will provide site survey data for future drilling and will increase the overall understanding of Antarctica's hidden ice and geologic records. The project involves international collaboration and leveraging of internationally collected data. The SPICECAP project will train new interdisciplinary scientists at the undergraduate, graduate, and postdoctoral levels. Technical description: This study focuses on processing and interpretation of internationally collected aerogeophysical data from the Southern Plateau of the East Antarctic Ice Sheet. The data include ice penetrating radar data, laser altimetry, gravity and magnetics. The project will provide information on geological trends under the ice, the topography and character of the ice/rock interface, and the stratigraphy of the ice. The project will also provide baseline site characterization for future drilling. Future drilling sites and deep ice cores for old ice require that the base of the ice sheet be frozen to the bed (i.e. no free water at the interface between rock and ice) and the assessment will map the extent of frozen vs. thawed areas. Specifically, three main outcomes are anticipated for this project. First, the study will provide an assessment of the viability of Titan Dome, a subglacial highland region located near South Pole, as a potential old ice drilling prospect. The assessment will include determining the hydraulic context of the bed by processing and interpreting the radar data, ice sheet mass balance through time by mapping englacial reflectors in the ice and connecting them to ice stratigraphy in the recent South Pole, and ice sheet geometry using laser altimetry. Second, the study will provide an assessment of the geological context of the Titan Dome region with respect to understanding regional geologic boundaries and the potential for bedrock sampling. For these two goals, we will use data opportunistically collected by China, and the recent PolarGAP dataset. Third, the study will provide an assessment of the risk posture for RAID site targeting in the Titan Dome region, and the Dome C region. This will use a high-resolution dataset the team collected previously at Dome C, an area similar to the coarser resolution data collected at Titan Dome, and will enable an understanding of what is missed by the wide lines spacing at Titan Dome. Specifically, we will model subglacial hydrology with and without the high resolution data, and statistically examine the detection of subglacial mountains (which could preserve old ice) and subglacial lakes (which could destroy old ice), as a function of line spacing.
Overview: In order to close the global overturning circulation, high-density deep- and bottom waters produced at high latitudes must be made less dense and upwell to shallower depths. Available observations from the subtropical South Atlantic indicate that the bulk of the mixing in the deep ocean there takes place over the topographically rough Mid-Atlantic Ridge, in particular in the quasi-regularly spaced "fracture zone canyons" corrugating the ridge flanks. There, dense water is advected toward the ridge crest (i.e. upwelled) by persistent along-valley currents that flow down the unidirectional density gradients, which are maintained by strong turbulence (diapycnal mixing). Most of the data on which these inferences are based were collected during the Brazil Basin Tracer Release Experiment (BBTRE) along a single ridge-flank canyon in the western South Atlantic near 22S where previous analyses have shown that both tidal mixing and overflow processes are important. Therefore, it is likely that both processes must be considered in order to understand and parameterize the effects of turbulence and mixing in the canyons corrugating the flanks of all slow-spreading ridges, which make up large fractions of the sea floor, in particular in the Atlantic, Indian and Southern Oceans. The primary aim of this follow-on project is to improve our understanding of the dynamics over the corrugated flanks of slow-spreading mid-ocean ridges. Due to the coarse sampling resolution and choice of station locations it is not possible to answer important questions, such as the relative importance of tidal and sill mixing, from the BBTRE data. Therefore, high-resolution surveys of hydrography, three-dimensional flow, turbulence and mixing will be carried out in two neighboring canyons and over the intervening topographic spur in the BBTRE region to determine the relative contributions of tidal and sill-related mixing. Furthermore, profiling moorings deployed on two nearby sill regions will be used to derive time series of spatially integrated mixing related buoyancy fluxes and to investigate the strong but unexplained sub-inertial variability of the along-canyon flow recorded previously. Additionally, three small moorings will be deployed in saddles between the two canyons to investigate inter-canyon exchange. The data analysis will include available data from previous experiments, including a set of tracer profiles that has not been analyzed before. Intellectual Merit: The corrugated flanks of slow-spreading ridges cover large areas of the sea floor of several major ocean basins. Therefore, understanding the dynamics in the ~100 km of ridge-flank canyons and its effects on the buoyancy and upwelling budget of the abyssal ocean is of global significance. In addition to determining the relative importance of tidal mixing and cross-sill flows in two canyons, the temporal variability of turbulence and mixing from tidal to yearly time scales will be investigated to gain insights into the forcing of the along-canyon flows, the exchange between neighboring canyons, and the eventual fate of the canyon waters. Broader Impacts: It is anticipated that insights gained during this project will improve our understanding of abyssal mixing in many different regions with similar bottom topography and provide the basis for better parameterizations of the effects of turbulence and mixing in large-scale circulation and climate models that cannot resolve these small-scale processes. As part of the project, a graduate student and a post-doctoral researcher will be trained in all aspects of observational physical oceanography, from data acquisition to interpretation.
Modeling fluctuations in the extent of the West Antarctic Ice Sheet (WAIS) over time is a principal goal of the glaciological community. These models will provide a critical basis for predictions of future sea level change, and therefore this work great societal relevance. The mid-Pliocene time interval is of particular interest, as it is the most recent period in which global temperatures were warmer and atmospheric CO2 concentrations may have been higher than current levels. However, observational constraints on fluctuations in the WAIS older than the last glacial maximum are rare. The investigators propose to collect geochemical data from the Ohio Range and Scott Glacier to quantify past variability in the height of the WAIS. Limited available cosmogenic nuclide data are broadly consistent with a model indicating that Pliocene WAIS elevations and volumes were smaller than at present, and that WAIS collapse was common. The PIs will use geologic observations and cosmogenic nuclide concentrations from bedrock samples at multiple locations and at multiple elevations, including sub-ice samples, to constrain WAIS ice volume changes in a "dipstick" like fashion. Data obtained from the proposed research will provide targets for data-ice sheet model comparisons to accurately characterize Plio-Pleistocene and future WAIS behavior. As part of this project, the investigators will work with the Natural History Museum and the Earth & Planetary Science department at Harvard to develop an exhibit that will become part of the Museum's recently opened Earth and Planetary Science Gallery. The project involves mentoring of a female graduate student as well as an undergraduate student.
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.
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.
Nontechnical project description Globally, 500 million people live near and are threatened by active volcanoes. An important step in mitigating volcanic hazards is understanding the variables that influence the explosivity of eruptions. The rate at which a magma ascends from the reservoir within the Earth to the surface is one such variable. However, magma ascent rates are particularly difficult to determine because of the lack of reliable methods for investigating the process. This research applies a new approach to study magma storage depths and ascent rates at the Erebus volcanic province of Antarctica, one of Earth's largest alkaline volcanic centers. Small pockets of magma that become trapped within growing olivine crystals are called melt inclusions. The concentrations of water and carbon dioxide in these melt inclusions preserve information on the depth of magma reservoirs. Changes to the concentration and isotopic composition of water in the inclusions provide information on how long it took for the host magma to rise to the surface. In combination, these data from samples of olivine-rich volcanic deposits in the Erebus volcanic province will be used to determine the depths at which magmas are stored and their ascent rates. The project results will provide a framework for understanding volcanic hazards associated with alkaline volcanism worldwide. In addition, this project facilitates collaboration among three institutions, and provides an important educational opportunity for a postdoctoral researcher. Technical project description The depths at which magmas are stored, their pre-eruptive volatile contents, and the rates at which they ascend to the Earth's surface are important controls on the dynamics of volcanic eruptions. Basaltic magmas are likely to be vapor undersaturated as they begin their ascent from the mantle through the crust, but volatile solubility drops with decreasing pressure. Once vapor saturation is achieved and the magma begins to degas, its pre-eruptive volatile content is determined largely by the depth at which it resides within the crust. Magma stored in deeper reservoirs tend to experience less pre-eruptive degassing and to be richer in volatiles than magma shallower reservoirs. Eruptive style is influenced by the rate at which a magma ascends from the reservoir to the surface through its effect on the efficiency of vapor bubble nucleation, growth, and coalescence. The proposed work will advance our understanding of pre-eruptive storage conditions and syn-eruptive ascent rates through a combined field and analytical research program. Volatile measurements from olivine-hosted melt inclusions will be used to systematically investigate magma storage depths and ascent rates associated with alkaline volcanism in the Erebus volcanic province. A central goal of the project is to provide a spatial and temporal framework for interpreting results from studies of present-day volcanic processes at Mt Erebus volcano. The Erebus volcanic province of Antarctica is especially well suited to this type of investigation because: (1) there are many exposed mafic scoria cones, fissure vents, and hyaloclastites (exposed in sea cliffs) that produced rapidly quenched, olivine-rich tephra; (2) existing volatile data for Ross Island MIs show that magma storage was relatively deep compared to many mafic volcanic systems; (3) some of the eruptive centers ejected mantle xenoliths, allowing for comparison of ascent rates for xenolith-bearing and xenolith-free eruptions, and comparison of ascent rates for those bearing xenoliths with times estimated from settling velocities; and (4) the cold, dry conditions in Antarctica result in excellent tephra preservation compared to tropical and even many temperate localities. The project provides new tools for assessing volcanic hazards, facilitates collaboration involving researchers from three different institutions (WHOI, U Wyoming, and U Oregon), supports the researchers' involvement in teaching, advising, and outreach, and provides an educational opportunity for a promising young postdoctoral researcher. Understanding the interrelationships among magma volatile contents, reservoir depths, and ascent rates is vital for assessing volcanic hazards associated with alkaline volcanism across the globe.
Part I: Nontechnical One of the most interesting historical records that science can provide is contained in the ice of Antarctica. Layer by layer over hundreds of thousands of years, snow has precipitated on the ice sheet, become compacted, and turned into additional ice. Any dust or other impurities in the air or snow have been precipitated as well and thus each snowfall leaves a snapshot record of the atmosphere that existed at or near the time of deposition. A detailed chronology of volcanic eruptions can be obtained from the ice layers where ash and other volcanic products were deposited. Normally, the analysis of volcanic layers requires the physical extraction of a core from the ice sheet; however, chronologies from cores have discontinuities and are difficult, time-consuming, and expensive to obtain. Borehole logging is a measurement method where one lowers instrumentation into a drilled hole in the ice, whether or not core has been retrieved. To date, this technology has only been used to measure optical systems to identify volcanic ash and other impurity layers. In this program, a profiling technology will be developed that measures the conductivity of the ice. A radio-frequency emitter lowered into the borehole will create a return signal that changes depending on the local conductivity, which depends on the concentration of dissolved ions. For example, dissolved sulfates are a critical marker of volcanic activity that may not be coincident with deposited ash. Other dissolved ions, such as chloride, can be indicative of other processes. It is expected that this borehole profiling instrument will be able to help rapidly identify volcanic eruptions that had potentially global impact, distinguish between different dissolved ions via their frequency dependencies, and assist in establishing chronologies between different ice cores and boreholes. Part II: Technical Description Borehole logging of the polar ice sheets is one of the most important methods that earth scientists have to identify and date volcanic eruptions. However, current technology only indicates the presence and depth of ash from an eruption. In order to extract more detailed information, one must obtain an ice core, and laboriously measure each section in the laboratory using electrical conductivity or dielectric measurements to determine the presence or absence of dissolved sulfate and its location relative to the corresponding ash, if any. This program will investigate and demonstrate a borehole logging-compatible radio-frequency dielectric sensor to detect and measure spikes in dissolved major ions chemistry in ice, particularly in intervals corresponding to volcanically produced sulfates. The sulfate layers are one of the primary signatures of volcanic products. However, other ions, such as chlorides, calcium, and others are also commonly seen in ice, and the dielectric logging technology of this program would also measure these. It is expected that certain sets of ions will be distinguishable by their frequency dependencies. This technique could guide other investigators, who are using conventional core scanning and sampling methods, to regions of special interest in corresponding core. We plan to construct a ring-based electrode system and test this system on a variety of artificial ice boreholes and ice cores. This unit will not include a pressure vessel or other borehole logger packing. We will test different means of applying electrical signals including short pulses and periodic waves. We will further utilize differential measurements with low noise circuits and filters to achieve maximum sensitivity. We will correlate the signals extracted with known molarities of sulfates and other ions and measured ECM records. We will perform scaled-down experiments using real ice cores stored in Bay?s lab at UC Berkeley. This will permit testing of different designs in ice with natural impurities and polycrystalline structure. This small collection includes cores from a variety of locations in Antarctica and Greenland, and a variety of ages as old as a million years.
Beginning with the discovery of a "curious valley" in 1903 by Captain Scott, the McMurdo Dry Valleys (MDV) in Antarctica have been impacted by humans, although there were only three brief visits prior to 1950. Since the late 1950's, human activity in the MDV has become commonplace in summer, putting pressure on the region's fragile ecosystems through camp construction and inhabitation, cross-valley transport on foot and via vehicles, and scientific research that involves sampling and deployment of instruments. Historical photographs, put alongside information from written documentation, offer an invaluable record of the changing patterns of human activity in the MDV. Photographic images often show the physical extent of field camps and research sites, the activities that were taking place, and the environmental protection measures that were being followed. Historical photographs of the MDV, however, are scattered in different places around the world, often in private collections, and there is a real danger that many of these photos may be lost, along with the information they contain. This project will collect and digitize historical photographs of sites of human activity in the MDV from archives and private collections in the United States, New Zealand, and organize them both chronologically and spatially in a GIS database. Sites of past human activities will be re-photographed to provide comparisons with the present, and re-photography will assist in providing spatial data for historical photographs without obvious location information. The results of this analysis will support effective environmental management into the future. The digital photo archive will be openly available through the McMurdo Dry Valleys Long Term Ecological Research (MCM LTER) website (www.mcmlter.org), where it can be used by scientists, environmental managers, and others interested in the region. The central question of this project can be reformulated as a hypothesis: Despite an overall increase in human activities in the MDV, the spatial range of these activities has become more confined over time as a result of an increased awareness of ecosystem fragility and efforts to manage the region. To address this hypothesis, the project will define the spatial distribution and temporal frequency of human activity in the MDV. Photographs and reports will be collected from archives with polar collections such as the National Archives of New Zealand in Wellington and Christchurch and the Byrd Polar Research Center in Ohio. Private photograph collections will be accessed through personal connections, social media, advertisements in periodicals such as The Polar Times, and other means. Re-photography in the field will follow established techniques and will create benchmarks for future research projects. The spatial data will be stored in an ArcGIS database for analysis and quantification of the human footprint over time in the MDV. The improved understanding of changing patterns of human activity in the MDV provided by this historical photo archive will provide three major contributions: 1) a fundamentally important historic accounting of human activity to support current environmental management of the MDV; 2) defining the location and type of human activity will be of immediate benefit in two important ways: a) places to avoid for scientists interested in sampling pristine landscapes, and, b) targets of opportunity for scientists investigating the long-term environmental legacy of human activity; and 3) this research will make an innovative contribution to knowledge of the environmental history of the MDV.
This project will develop a record of the stable-isotope ratios of water from an ice core at the South Pole, Antarctica. Water-isotope ratio measurements provide a means to determine variability in temperature through time. South Pole is distinct from most other locations in Antarctica in showing no warming in recent decades, but little is known about temperature variability in this location prior to the installation of weather stations in 1957. The measurements made as part of this project will result in a much longer temperature record, extending at least 40,000 years, aiding our ability to understand what controls Antarctic climate, and improving projections of future Antarctic climate change. Data from this project will be critical to other investigators working on the South Pole ice core, and of general interest to other scientists and the public. Data will be provided rapidly to other investigators and made public as soon as possible. This project will obtain records of the stable-isotope ratios of water on the ice core currently being obtained at South Pole. The core will reach a depth of 1500 m and an age of 40,000 years. The project will use laser spectroscopy to obtain both an ultra-high-resolution record of oxygen 18/16 and deuterium-hydrogen ratios, and a lower-resolution record of oxygen 17/16 ratios. The high-resolution measurements will be used to aid in dating the core, and to provide estimates of isotope diffusion that constrain the process of firn densification. The novel 17/16 measurement provides additional constraints on the isotope fractionation due to the temperature-dependent supersaturation ratio, which affects the fractionation of water during the liquid-solid condensate transition. Together, these techniques will allow for improved accuracy in the use of the water isotope ratios as proxies for ice-sheet temperature, sea-surface temperature, and atmospheric circulation. The result will be a record of decadal through centennial and millennial scale climate change in a climatically distinct region in East Antarctica that has not been previously sampled by deep ice coring. The project will support a graduate student who will be co-advised by faculty at the University of Washington and the University of Colorado, and will be involved in all aspects of the work.
Bay/1443566 This award supports the deployment and analysis of data from an oriented laser dust logger in the South Pole ice core borehole to complement study of the ice core record. Before the core is even processed, data from the borehole probe will immediately determine the depth-age relationship, augment 3D mapping of South Pole stratigraphy, aid in searches for the oldest ice in Antarctica, and reveal layers of volcanic or extraterrestrial fallout. Regarding the intellectual merit, the oriented borehole log will be essential for investigating features in the ice sheet that may have implications for ice core chronology, ice flow, ice sheet physical properties and stability in response to climate change. The tools and techniques developed in this program have applications in glaciology, biogeoscience and exploration of other planetary bodies. The program aims for a deeper understanding of the consequences and causes of abrupt climate change. The broader impacts of the project are that it will include outreach and education, providing a broad training ground for students and post-docs. Data and metadata will be made available through data centers and repositories such as the National Snow and Ice Data Center web portal. The laser dust logger detects reproducible paleoclimate features at sub-centimeter depth scale. Dust logger data are being used for synchronizing records and dating any site on the continent, revealing accumulation anomalies and episodes of rapid ice sheet thinning, and discovering particulate horizons of special interest. In this project we will deploy a laser dust logger equipped with a magnetic compass to find direct evidence of preferentially oriented dust. Using optical scattering measurements from IceCube calibration studies at South Pole and borehole logs at WAIS Divide, we have detected a persistent anisotropy correlated with flow and crystal fabric which suggests that the majority of insoluble particulates must be located within ice grains. With typical concentrations of parts-per-billion, little is known about the location of impurities within the polycrystalline structure of polar ice. While soluble impurities are generally thought to concentrate at inter-grain boundaries and determine electrical conductivity, the fate of insoluble particulates is much less clear, and microscopic examinations are extremely challenging. These in situ borehole measurements will help to unravel intimate relationships between impurities, flow, and crystal fabric. Data from this project will further develop a unique record of South Pole surface roughness as a proxy for paleowind and provide new insights for understanding glacial radar propagation. This project has field work in Antarctica.
Brook 1543267 Approximately half of the human caused carbon dioxide emissions to the atmosphere are absorbed by the ocean, which reduces the amount of global warming associated with these emissions. Much of this carbon uptake occurs in the Southern Ocean around Antarctica, where water from the deep ocean comes to the surface. How much water "up-wells," and therefore how much carbon is absorbed, is believed to depend on the strength and location of the major westerly winds in the southern hemisphere. These wind patterns have been shifting southward in recent decades, and future changes could impact the global carbon cycle and promote the circulation of relatively warm water from the deep ocean on to the continental shelf, which contributes to enhanced Antarctic ice melt and sea level rise. Understanding of the westerly winds and their role in controlling atmospheric carbon dioxide levels and the circulation of ocean water is therefore very important. The work supported by this award will study past movement of the SH westerlies in response to natural climate variations. Of particular interest is the last deglaciation (20,000 to 10,000 years ago), when the global climate made a transition from an ice age climate to the current warm period. During this period, atmospheric carbon dioxide rose from about 180 ppm to 270 parts per million, and one leading hypothesis is that the rise in carbon dioxide was driven by a southward movement of the southern hemisphere westerlies. The broader impacts of the work include a perspective on past movement of the southern hemisphere westerlies and their link to atmospheric carbon dioxide, which could guide projections of future oceanic carbon dioxide uptake, with strong societal benefits; international collaboration with German scientists; training of a postdoctoral investigator; and outreach to public schools. This project will investigate whether the abundance of a noble gas, krypton-86, trapped in Antarctic ice cores, records atmospheric pressure variability, and whether or not this pressure variability can be used to infer past movement of the Southern Hemisphere westerly winds. The rationale for the project is that models of air movement in the snow pack (firn) in Antarctica indicate that pressure variations drive air movement that disturbs the normal enrichment in krypton-86 caused by gravitational settling of gases. Calculations predict that the krypton-86 deviation from gravitational equilibrium reflects the magnitude of pressure variations. In turn, atmospheric data show that pressure variability over Antarctica is linked to the position of the southern hemisphere westerly winds. Preliminary data from the West Antarctic Ice Sheet (WAIS) Divide ice core show a large excursion in krypton-86 during the transition from the last ice age to the current warm period. The investigators will perform krypton-86 analysis on ice core and firn air samples to establish whether the Kr-86 deviation is linked to pressure variability, refine the record of krypton isotopes from the WAIS Divide ice core, investigate the role of pressure variability in firn air transport using firn air models, and investigate how barometric pressure variability in Antarctica is linked to the position/strength of the SH westerlies in past and present climates.
Marine ecosystems under large ice shelves are thought to contain sparse, low-diversity plankton and seafloor communities due the low supply of food from productive sunlight waters. Past studies have shown sub-ice shelf ecosystems to change in response to altered oceanographic processes resulting from ice-shelve retreat. However, information on community changes and ecosystem structure under ice shelves are limited because sub-ice-shelf ecosystems have either been sampled many years after ice-shelf breakout, or have been sampled through small boreholes, yielding extremely limited spatial information. The recent breakout of the A-68 iceberg from the Larsen C ice shelf in the western Weddell Sea provides an opportunity to use a ship-based study to evaluate benthic communities and water column characteristics in an area recently vacated by a large overlying ice shelf. The opportunity will allow spatial assessments at the time of transition from an under ice-shelf environment to one initially exposed to conditions more typical of a coastal Antarctic marine setting. This RAPID project will help determine the state of a coastal Antarctic ecosystem newly exposed from ice-shelf cover and will aid in understanding of rates of community change during transition. The project will conduct a 10-day field program, allowing contrasts to be made of phytoplankton and seafloor megafaunal communities in areas recently exposed by ice-shelf loss to areas exposed for many decades. The project will be undertaken in a collaborative manner with the South Korean Antarctic Agency, KOPRI, by participating in a cruise in March/May 2018. Combining new information in the area of Larsen C with existing observations after the Larsen A and B ice shelf breakups further to the north, the project is expected to generate a dataset that can elucidate fundamental processes of planktonic and benthic community development in transition from food-poor to food-rich ecosystems. The project will provide field experience to two graduate students, a post-doctoral associate and an undergraduate student. Material from the project will be incorporated into graduate courses and the project will communicate daily work and unfolding events through social media and blogs while they explore this area of the world that is largely underexplored. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Southern Ocean surrounding Antarctica is changing rapidly in response to Earth's warming climate. These changes will undoubtedly influence communities of primary producers (the organisms at the base of the food chain, particularly plant-like organisms using sunlight for energy) by altering conditions that influence their growth and composition. Because primary producers such as phytoplankton play an important role in global biogeochemical cycling, it is essential to understand how they will respond to changes in their environment. The growth of phytoplankton in certain regions of the Southern Ocean is constrained by steep gradients in chemical and physical properties that vary in both space and time. Light and iron have been identified as key variables influencing phytoplankton abundance and distribution within Antarctic waters. Microscopic algae known as diatoms are dominant members of the phytoplankton and sea ice communities, accounting for significant proportions of primary production. The overall objective of this project is to identify the molecular bases for the physiological responses of polar diatoms to varying light and iron conditions. The project should provide a means of evaluating the extent these factors regulate diatom growth and influence net community productivity in Antarctic waters. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. It will facilitate the teaching and learning of polar-related topics by translating the research objectives into readily accessible educational materials for middle-school students. This project will also provide funding to enable a graduate student and several undergraduate students to be trained in the techniques and perspectives of modern biology. Although numerous studies have investigated how polar diatoms are affected by varying light and iron, the cellular mechanisms leading to their distinct physiological responses remain unknown. Using comparative transcriptomics, the expression patterns of key genes and metabolic pathways in several ecologically important polar diatoms recently isolated from Antarctic waters and grown under varying iron and irradiance conditions will be examined. In addition, molecular indicators for iron and light limitation will be developed within these polar diatoms through the identification of iron- and light-responsive genes -- the expression patterns of which can be used to determine their physiological status. Upon verification in laboratory cultures, these indicators will be utilized by way of metatranscriptomic sequencing to examine iron and light limitation in natural diatom assemblages collected along environmental gradients in Western Antarctic Peninsula waters. In order to fully understand the role phytoplankton play in Southern Ocean biogeochemical cycles, dependable methods that provide a means of elucidating the physiological status of phytoplankton at any given time and location are essential.
The Western Antarctic Peninsula is experiencing climate change at one of the fastest rates of anywhere around the globe. Accelerated climate change is likely to affect the many benthic marine invertebrates that live within narrow temperature windows along the Antarctic Continental Shelf in presently unidentified ways. At present however, there are few data on the physiological consequences of climate change on the sensitive larval stages of cold-water corals, and none on species living in thermal extremes such as polar waters. This project will collect the larvae of the non-seasonal, brooding scleractinian Flabellum impensum to be used in a month-long climate change experiment at Palmer Station. Multidisciplinary techniques will be used to examine larval development and cellular stress using a combination of electron microscopy, flow cytometry, and Inductively Coupled Plasma Mass Spectometry. Data from this project will form the first systematic study of the larval stages of polar cold-water corals, and how these stages are affected by temperature stress at the cellular and developmental level. Cold-water corals have been shown to be important ecosystem engineers, providing habitat for thousands of associated species, including many that are of commercial importance. Understanding how the larvae of these corals react to warming trends seen today in our oceans will allow researchers to predict future changes in important benthic communities around the globe. Associated education and outreach include: 1) Increasing student participation in polar research by involving postdoctoral and undergraduate students in the field and research program; ii) promotion of K-12 teaching and learning programs by providing information via a research website, Twitter, and in-school talks in the local area; iii) making the data collected available to the wider research community via peer reviewed published literature and iv) reaching a larger public audience through such venues as interviews in the popular media, You Tube and other popular media outlets, and local talks to the general public.
There is compelling historical evidence that the West Antarctic Ice Sheet (WAIS) is vulnerable to rapid retreat and collapse. Recent observations, compared to observations made 20-30 years before, indicate that both ice shelves (thick ice with ocean below) and land ice (thick ice with land below), are now melting at a much faster rate. Some numerical models suggest that significant ice retreat may begin within many of our lifetimes, starting with the abrupt collapse of Pine Island and Thwaites Glaciers in the next 50 years. This may be followed by retreat of much of the WAIS and then the collapse of parts of the East Antarctic ice sheet (EAIS). This research project will assess the extent to which global ocean circulation and climate will be impacted if enormous volumes of fresh water and ice flow into the Southern Ocean. It will establish whether a rapid collapse of WAIS in the near-future poses any significant threat to the stability of modern-day climate and human society. This is a topic that has so far received little attention as most prior research has focused on the response of climate to melting the Greenland ice sheet. Yet model simulations predict that the volumes of fresh water and ice released from Antarctica in the next few centuries could be up at least ten-times larger than from Greenland. The Intellectual Merit of this project stems from its ability to establish a link between the physical Antarctic system (ice sheet dynamics, fresh water discharge and iceberg calving) and global climate. The PIs (Principal Investigators) will assess the sensitivity of ocean circulation and climate to increased ice sheet melt using a combination of ocean, iceberg, ice sheet and climate models. Results from this study will help identify areas of the ice sheet that are vulnerable to collapse and also regions of the ocean where a significant freshening will have a considerable impact on climate, and serve to guide the deployment of an observational monitoring system capable of warning us when ice and fresh water discharge start to approach levels capable of disrupting ocean circulation and global climate. This project will support and train two graduate students, and each PI will be involved with local primary and secondary schools, making presentations, mentoring science fair projects, and contributing to curriculum development. A novel, web-based, interactive, cryosphere learning tool will be developed to help make school children more aware of the importance of the Polar Regions in global climate, and this software will be introduced to science teachers at a half day workshop organized by the UMass STEM Education Institute. Recent numerical simulations using a continental ice sheet/shelf model show the potential for more rapid and greater Antarctic ice sheet retreat in the next 50-300 years (under the full range of IPCC RCP (Intergovernmental Panel on Climate Change, Representative Concentration Pathways) future warming scenarios) than previously projected. Exactly how the release of enormous volumes of ice and fresh water to the Southern Ocean will impact global ocean circulation and climate has yet to be accurately assessed. This is in part because previous model simulations were too coarse to accurately resolve narrow coastal boundary currents, shelf breaks, fronts, and mesoscale eddies that are all very important for realistically simulating fresh water transport in the ocean. In this award, future projections of fresh water discharge and iceberg calving from Antarctic will be used to force a high resolution eddy-resolving ocean model (MITgcm) coupled to a new iceberg module and a fully-coupled global climate model (CCSM4). High resolution ocean/iceberg simulations will determine the role of mesoscale eddies in freshwater transport and give new insight into how fresh water is advected to far-field locations, including deep water formation sites in the North Atlantic. These simulations will provide detailed information about subsurface temperatures and changes in ocean circulation close to the ice front and grounding line. An accompanying set of fully coupled climate model simulations (NCAR CCSM4) will identify multidecadal-to-centennial changes in the climate system triggered by increased high-latitude Southern Ocean freshwater forcing. Particular attention will be given to changes in the strength of the Atlantic Meridional Overturning Circulation (AMOC), wind stress, sea ice formation, and global temperatures. In doing so, this project will more accurately determine whether abrupt and potentially catastrophic changes in global climate are likely to be triggered by changes in the Antarctic system in the near-future.
Climate change projections for this century suggest that the Southern Ocean will be the first region to be affected by seawater chemistry changes associated with enhanced carbon dioxide (CO2). Additionally, regions of the Southern Ocean are warming faster than any other locations on the planet. Ocean acidification and warming may act synergistically to impair the performance of different organisms by simultaneously increasing metabolic needs and reducing oxygen transport. However, no studies have measured krill acid-base regulation, metabolism, growth, or reproduction in the context of ocean acidification or synergistic 'greenhouse' conditions of elevated CO2 and temperature. In the present project, the investigators will conduct both short and prolonged exposure experiments at Palmer Station, Antarctica to determine the responses of Euphausia superba to elevated CO2 and temperature. The investigators will test hypotheses related to acid-base compensation and acclimation of various life stages of krill to elevated CO2 and temperature. Furthermore, they will determine these impacts on feeding, respiration, metabolism, growth, and reproduction. The Antarctic krill, Euphausia superba, is a key component of Antarctic food webs as they are a primary food source for many of the top predators in the Southern Ocean including baleen whales, seals, penguins, and other sea birds. This project will determine the responses of Antarctic krill exposed to elevated CO2 and temperature and whether or not krill have the capacity to fully compensate under future ocean conditions. The proposed field effort will be complemented by an extensive broader impact effort focused on bringing marine science to both rural and urban high school students in the Midwest (Kansas). The core educational objectives of this proposal are to 1) instruct students about potential careers in marine science, 2) engage students and promote their interest in the scientific process, critical thinking, and applications of science, mathematics, and technology, and 3) and increase student and teacher awareness and understanding of the oceans and global climate change, with special focus on the Western Antarctic Peninsula region. Finally, this project will engage undergraduate and graduate students in the production, analysis, presentation and publication of datasets.
Intellectual Merit: The PI requests support to analyze sediments from multi-cores and mega-cores previously collected from beneath the former Larsen B and Larsen A ice shelves. These unique cores will allow the PI to develop a time-integrated understanding of the benthic response to ice shelf collapse off the East Antarctic Peninsula over time periods as short as 5 years following ice shelf collapse up to >170 years after collapse. High latitudes are responding to climate change more rapidly than the rest of the planet and the disappearance of ice shelves are a key manifestation of climate warming. The PI will investigate the newly created benthic environments and associated ecosystems that have resulted from the re-initiation of fresh planktonic material to the sediment-water interface. This proposal will use a new geochemical technique, based on naturally occurring 14C that can be used to assess the distribution and inventory of recently produced organic carbon accumulating in the sediments beneath the former Larsen A and B ice shelves. The PI will couple 14C measurements with 210Pb analyses to assess turnover times for sedimentary labile organic matter. By comparing the distributions and inventories of labile organic matter as well as the bioturbation intensities among different locations as a function of time following ice shelf collapse/retreat, the nature and timing of the benthic response to ice shelf collapse can be assessed. Broader impacts: This study will provide important information characterizing changes occurring on the seafloor after the collapse of ice shelves. This research will support the research project of a graduate student. This project brings together researchers from both the European community and the LARISSA Project.
Like no other region on Earth, the northern Antarctic Peninsula represents a spectacular natural laboratory of climate change and provides the opportunity to study the record of past climate and ecological shifts alongside the present-day changes in one of the most rapidly warming regions on Earth. This award supports the cryospheric and oceano-graphic components of an integrated multi-disciplinary program to address these rapid and fundamental changes now taking place in Antarctic Peninsula (AP). By making use of a marine research platform (the RV NB Palmer and on-board helicopters) and additional logistical support from the Argentine Antarctic program, the project will bring glaciologists, oceanographers, marine geologists and biologists together, working collaboratively to address fundamentally interdisciplinary questions regarding climate change. The project will include gathering a new, high-resolution paleoclimate record from the Bruce Plateau of Graham Land, and using it to compare Holocene- and possibly glacial-epoch climate to the modern period; investigating the stability of the remaining Larsen Ice Shelf and rapid post-breakup glacier response ? in particular, the roles of surface melt and ice-ocean interactions in the speed-up and retreat; observing the contribution of, and response of, oceanographic systems to ice shelf disintegration and ice-glacier interactions. Helicopter support on board will allow access to a wide range of glacial and geological areas of interest adjacent to the Larsen embayment. At these locations, long-term in situ glacial monitoring, isostatic uplift, and ice flow GPS sites will be established, and high-resolution ice core records will be obtained using previously tested lightweight drilling equipment. Long-term monitoring of deep water outflow will, for the first time, be integrated into changes in ice shelf extent and thickness, bottom water formation, and multi-level circulation by linking near-source observations to distal sites of concentrated outflow. The broader impacts of this international, multidisciplinary effort are that it will significantly advance our understanding of linkages amongst the earth's systems in the Polar Regions, and are proposed with international participation (UK, Spain, Belgium, Germany and Argentina) and interdisciplinary engagement in the true spirit of the International Polar Year (IPY). It will also provide a means of engaging and educating the public in virtually all aspects of polar science and the effects of ongoing climate change. The research team has a long record of involving undergraduates in research, educating high-performing graduate students, and providing innovative and engaging outreach products to the K-12 education and public media forums. Moreover, forging the new links both in science and international Antarctic programs will provide a continuing legacy, beyond IPY, of improved understanding and cooperation in Antarctica.
This project will support two training courses that will introduce early-career scientists from a wide range of disciplinary backgrounds to key issues in polar science, and especially to provide the opportunity to gain hands-on experience in Antarctic field activities. Antarctica is an ideal location to study a wide variety of questions in biology. However, few students and early-career scientists have the opportunity to work on-site in Antarctica unless they are directly associated with a senior scientist who has a funded Antarctic project. The project will further the NSF goal of training new generations of scientists by providing hands-on training in Antarctica during one course at Palmer Station in 2016 and another at McMurdo Station in 2018. This represents a continuation of nine previous courses at McMurdo Station which have a proven record of introducing participants to Antarctic science under realistic field conditions, providing opportunities to understand and appreciate the complexities and logistical challenges of undertaking science in Antarctica, enhancing the professional careers of the participants, and increasing international collaborations for early-career scientists. The proposed training courses will be open to Ph.D. students and post-doctoral scientists who have interests in the study of Antarctic marine organisms to help prepare them for success in developing their own independent research programs in polar regions. Long-standing and recent questions in evolution and ecology of Antarctic organisms will be examined with 1) field collections, 2) physiological experiments on whole organisms, 3) studies of isolated cells and tissues, 4) experiments on macromolecular processes (e.g., enzymes), and 5) molecular biological analyses.
Paragraph for Public Audiences: Many of the natural processes that modify the landscape inhabited by humans occur over very long timescales, making them difficult to observe. Exceptions include rare catastrophic events such as earthquakes, volcanic eruptions, and floods that occur on short timescales. Many significant processes that affect the land and landscape that we inhabit operate on time scales imperceptible to humans. One of these processes is wind transport of sand, with related impacts to exposed rock surfaces and man-made objects, including buildings, windshields, solar panels and wind-farm turbine blades. The goal of this project is to gain an understanding of wind erosion processes over long timescales, in the Antarctic Dry Valleys, a cold desert environment where there were no competing processes (such as rain and vegetation) that might mask the effects. The main objective is recovery of rock samples that were deployed in 1983/1984 at 11 locations in the Antarctic Dry Valleys, along with measurements on the rock samples and characterization of the sites. In the late 1980's and early 1990's some of these samples were returned and indicated more time was needed to accumulate information about the timescales and impacts of the wind erosion processes. This project will allow collection of the remaining samples from this experiment after 30 to 31 years of exposure. The field work will be carried out during the 2014/15 Austral summer. The results will allow direct measurement of the abrasion rate and hence the volumes and timescales of sand transport; this will conclude the longest direct examination of such processes ever conducted. Appropriate scaling of the results may be applied to buildings, vegetation (crops), and other aspects of human presence in sandy and windy locations, in order to better determine the impact of these processes and possible mitigation of the impacts. The project is a collaborative effort between a small business, Malin Space Science Systems (MSSS), and the University of Washington (UW). MSSS will highlight this Antarctic research on its web site, by developing thematic presentations describing our research and providing a broad range of visual materials. The public will be engaged through daily updates on a website and through links to material prepared for viewing in Google Earth. UW students will be involved in the laboratory work and in the interpretation of the results. Technical Description of Project: The goal of this project is to study the role of wind abrasion by entrained particles in the evolution of the McMurdo Dry Valleys in the Transantarctic Mountains. During the 1983 to 1984 field seasons, over 5000 rock targets were installed at five heights facing the 4 cardinal directions at 10 locations (with an additional site containing fewer targets) to study rates of physical weathering due primarily to eolian abrasion. In addition, rock cubes and cylinders were deployed at each site to examine effects of chemical weathering. The initial examination of samples returned after 1, 5, and 10 years of exposure, showed average contemporary abrasion rates consistent with those determined by cosmogenic isotope studies, but further stress that "average" should not be interpreted as meaning "uniform." The samples will be characterized using mass measurements wtih 0.01 mg precision balances, digital microphotography to compare the evolution of their surface features and textures, SEM imaging to examine the micro textures of abraded rock surfaces, and optical microscopy of thin sections of a few samples to examine the consequences of particle impacts extending below the abraded surfaces. As much as 60-80% of the abrasion measured in samples from 1984-1994 appears to have occurred during a few brief hours in 1984. This is consistent with theoretical models that suggest abrasion scales as the 5th power of wind velocity. The field work will allow return of multiple samples after three decades of exposure, which will provide a statistical sampling (beyond what is acquired by studying a single sample), and will yield the mass loss data in light of complementary environmental and sand kinetic energy flux data from other sources (e.g. LTER meteorology stations). This study promises to improve insights into one of the principal active geomorphic process in the Dry Valleys, an important cold desert environment, and the solid empirical database will provide general constraints on eolian abrasion under natural conditions.
Paragraph for Laypersons: This research focuses on the history of rock glaciers and buried glacial ice in the McMurdo Dry Valleys region of Antarctica. Rock glaciers are flowing mixtures of ice and sediments common throughout alpine and high-latitude regions on Earth and Mars. Despite similar appearances, rock glaciers can form under highly variable environmental and hydrological conditions. The main research questions addressed here are: 1) what environmental and climatological conditions foster long-term preservation of rock glaciers in Antarctica, 2) what role do rock glaciers play in Antarctic landscape evolution and the local water cycle, and 3) what can rock glaciers reveal about the extent and timing of previous glacial advances? The project will involve two Antarctic field seasons to image the interior of Antarctic rock glaciers using ground-penetrating radar, to gather ice cores for chemical analyses, and to gather surface sediments for dating. The Dry Valleys host the world?s southernmost terrestrial ecosystem (soil, stream and lake micro-organisms and mosses); rock glaciers and ground-ice are an important and poorly-studied source of meltwater and nutrients for these ecosystems. This research will shed light on the glacial and hydrological history of the Dry Valleys region and the general environmental conditions the foster rock glaciers, features that generally occur in warmer and/or wetter locations. The research will provide support for five graduate/undergraduate students, who will actively gather data in the field, followed by interpretation, dissemination and presentation of the data. Additionally, the researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities. A series of time-lapse images of hydrological processes, and videos of researchers in the field, will serve as a dramatic centerpiece in community and school presentations. Paragraph for Scientific Community: Rock glaciers are common in the McMurdo Dry Valleys, but are concentrated in a few isolated regions: western Taylor Valley, western Wright Valley, Pearse Valley and Bull Pass. The investigators hypothesize that the origin and age of these features varies by region: that rock glaciers in Pearse and Taylor valley originated as buried glacier ice, whereas rock glaciers in Wright Valley formed through permafrost processes, such as mobilization of ice-rich talus. To address these hypotheses, the project will: 1) develop relative and absolute chronologies for the rock glaciers through field mapping and optically stimulated luminescence dating of overlying sediments, 2) assess the origin of clean-ice cores through stable isotopic analyses, and 3) determine if present-day soil-moisture and temperature conditions are conducive to rock glacier formation/preservation. The proposed research will provide insight into the spatial and temporal distribution of buried glacier ice and melt-water-derived ground ice in the McMurdo Dry Valleys, with implications for glacial history, as well as the potential role of rock glaciers in the regional hydrologic cycle (and the role of ground-ice as a source for moisture and nutrient for local ecosystems). The project will provide general constraints on the climatic and hydrologic conditions that foster permafrost rock glaciers, features that generally occur under warmer and wetter conditions than those found in the present-day McMurdo Dry Valleys. The application of OSL and cosmogenic exposure dating is novel to rock glaciers, geomorphic features that have proven difficult to date, despite their ubiquity in Antarctica and their potential scientific importance. The research will provide support for five graduate/undergraduate students, who will participate in the field work, followed by interpretation, dissemination and presentation of the data. The researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities.
Marine paleoclimate archives show that approximately one million years ago Earth's climate transitioned from 40,000-year glacial /interglacial cycles to 100,000-year cycles. This award will support a study designed to map the distribution of one million year-old ice in the Allan Hills Blue Ice Area, Antarctica using state-of-the-art ground penetrating radar. The Allen Hills was demonstrated to contain a continuous record of the past 400,000 years and is also the collection location of the oldest ice samples (990,000 years) yet recovered. The maps resulting from this study will be used to select an ice-core drilling site at which a million-plus year-old continuous record of climate could be recovered. Ice cores contain the only kind of record to directly capture atmospheric gases and aerosols, but no ice-core-based climate record yet extends continuously beyond the past 800,000 years. A million-plus year-old record will allow better understanding of the major mechanisms and driving forces of natural climate variability in a world with 100,000-year glacial/interglacial cycles. The project will support two early career scientists in collaboration with senior scientists, as well as a graduate student, and will conduct outreach to schools and the public. The Allan Hills Blue Ice Area preserves a continuous climate record covering the last 400,000 years along an established glaciological flow line. Two kilometers to the east of this flow line, the oldest ice on Earth (~1 million years old) is found only 120 m below the surface. Meteorites collected in the area are reported to be as old as 1.8 million years, suggesting still older ice may be present. Combined, these data strongly suggest that the Allen Hills area could contain a continuous, well-resolved environmental record, spanning at least the last million years. As such, this area has been selected as an upcoming target for the new Intermediate Depth Ice Core Drill by the US Ice Core Working Group. This drill will recover a higher-quality core than previous dry drilling attempts. This project will conduct a comprehensive ground penetrating radar survey aimed at tracing the signature of the million-year-old ice layer throughout the region. The resulting map will be used to select a drill site from which an ice core containing the million-plus year-old continuous climate record will be collected. The proposed activities are a necessary precursor to the collection of the oldest known ice on Earth. Ice cores provide a robust reconstruction of past climate and extending this record beyond the 800,000 years currently available will open new opportunities to study the climate system. The data collected will also be used to investigate the bedrock and ice flow parameters favorable to the preservation of old ice, which may allow targeted investigation of other blue ice areas in Antarctica.
This award supports a three-year study of the ongoing deceleration and stick-slip motion of Whillans Ice Stream (WIS), West Antarctica. Understanding the dynamic behavior of ice streams is essential for predicting the future of the West Antarctic Ice Sheet (WAIS). Despite being one of the best-studied ice streams in Antarctica, the surprising flow characteristics of WIS continue to demand interdisciplinary research. Recent estimates indicate that the WIS may stagnate within 50 years, resulting in a significant change to the mass balance of the Siple Coast sector of West Antarctica. The reasons for the ongoing stagnation are not well known, and are possibly linked (causally or coincidentally) to the stick-slip behavior. Our recent work on WIS stick-slip motion suggest that all slip events nucleate from a common location on the ice stream, suggesting that a relatively small (approximately 10 km in diameter) region of the exerts fundamental control over the flow of this large ice stream (100s of km long and 100 kilometers wide). We hypothesize that this is a region of increased bed strength and our measurements will address that hypothesis. We will deploy a series of GPS receivers and seismometers on the ice stream to accurately locate the nucleation region so that a comprehensive ground based geophysical survey can be conducted to determine the physical properties of bed at the nucleation point. The ground geophysical program will consist of reflection seismic and ice-penetrating radar studies that will better constrain the properties of both the hypothesized higher-friction nucleation zone and the surrounding regions. Slip events also generate seismic energy that can be recorded 100s of km away from the ice stream, thus, the GPS and seismometer deployment will also aid us in relating seismic waveforms directly with the rapid motion that occurs during slip events. The increased ability to relate rupture processes with seismic emissions will allow us to use archived seismic records to explore changes in the behavior of WIS during the later half of the 20th century. Broader impacts of this study include improved knowledge ice sheet dynamics, which remain a poorly constrained component of the climate system, thus, limiting our ability to predict the Earth's response to climate change. The scientific work includes the education of two graduate students and continued training of one post-doctoral scholar, thus helping to train the next generation of polar scientists. We will expose the broader public to polar science through interactions with the media and by take advantaging of programs to include K-12 educators in our field work.
Abstract The Erebus Bay population of Weddell seals in Antarctica?s Ross Sea is the most southerly breeding population of mammal in the world, closely associated with persistent shore-fast ice, and one that has been intensively studied since 1968. The resulting long-term database, which includes data for 20,586 marked individuals, contains detailed population information that provides an excellent opportunity to study linkages between environmental conditions and demographic processes in the Antarctic. The population?s location is of special interest as the Ross Sea is one of the most productive areas of the Southern Ocean, one of the few pristine marine environments remaining on the planet, and, in contrast to the Antarctic Peninsula and Arctic, is undergoing a gradual lengthening of the sea-ice season. The work to be continued here capitalizes on (1) long-term data for individual seals and their polar environment; (2) experience collecting and analyzing data from the extensive study population; and (3) recent statistical advances in hierarchical modeling that allow for rigorous treatment of individual heterogeneity (in mark-recapture and body mass data) and inclusion of diverse covariates hypothesized to explain variation in fitness components. Covariates to be considered include traits of individuals and their mothers and environmental conditions throughout life. The study will continue to (1) provide detailed data on known-age individuals to other science projects and (2) educate and mentor the next generation of ecologists through academic and professional training and research experiences.
While changes in populations typically are tracked to gauge the impact of climate or habitat change, the process involves the response of individuals as each copes with an altered environment. In a study of Adelie penguins that spans 13 breeding seasons, results indicate that only 20% of individuals within a colony successfully raise offspring, and that they do so because of their exemplary foraging proficiency. Moreover, foraging appears to require more effort at the largest colony, where intraspecific competition is higher than at small colonies, and also requires more proficiency during periods of environmental stress. When conditions are particularly daunting, emigration dramatically increases, countering the long-standing assumption that Adélie penguins are highly philopatric. The research project will 1) determine the effect of age, experience and physiology on individual foraging efficiency; 2) determine the effect of age, experience, and individual quality on breeding success and survival in varying environmental and competitive conditions at the colony level; and 3) develop a comprehensive model for the Ross-Beaufort Island metapopulation dynamics. Broader impacts include training of interns, continuation of public outreach through the highly successful project website penguinscience.com, development of classroom materials and other standards-based instructional resources.
The emperor penguin dives deeper and longer, fasts longer, and endures the harshest weather conditions of all diving birds. It spends about four and half months per annum deep in Antarctic pack ice away from shore and stations, and thus is largely unavailable for study. This time includes preparation for the molt, and travel to the colony to breed, a time period in which great swings in body weight occur. This study will fill an important gap in what we know about the biology of the annual cycle of the emperor by examining the molt-post molt period. The P.I. proposes to traverse the Amundsen and Bellingshausen seas on the Oden, to locate and tag emperor penguins during the molt season. The objectives are to (1) Place satellite tags on 20 adult post molt birds to determine their route, rate of travel, and diving behavior as they return back to their breeding colonies, (2) Obtain an index of body condition, (3) Collect guano to determine the type of food consumed by emperor penguins in the region, (4) Conduct shipboard surveys to sight and plot the location and abundance of adult and juvenile birds on the ship's track. The PI hypothesizes that bird dives will be shallow during the initial post-molt phase, and that food will consist primarily of krill; that there will be differential dispersal of birds from the Ross Sea vs. Marie Byrd Land, with Ross Sea birds traveling farther; and that the greatest adult mortality occurs during the molt and early post molt period. Broader impacts include training of a post doc, a graduate student, and an aquarium volunteer. The P.I. also will present findings through a website, through public lectures, and in collaboration with the Birch aquarium.
Geochemical studies of single mineral grains in rocks can be probed to reconstruct the history of our planet. The mineral zircon (ZrSiO4) is of unique importance in that respect because of its reliability as a geologic clock due to its strong persistence against weathering, transport and changes in temperature and pressure. Uranium-Lead (U-Pb) dating of zircon grains is, perhaps, the most frequently employed method of extracting time information on geologic processes that shaped the continental crust, and has been used to constrain the evolution of continents and mountain belts through time. In addition, the isotopic composition of the element Hafnium (Hf) in zircon is used to date when the continental crust was generated by extraction of magma from the underlying mantle. Melting of rocks in the mantle and deep in the continental crust are key processes in the evolution of the continents, and they are recorded in the Hf isotopic signatures of zircon. Although the analytical procedures for U-Pb dating and Hf isotope analyses of zircon are robust now, our understanding of zircon growth and its exchange of elements and isotopes with its surrounding rock or magma are still underdeveloped. The focus of the proposed study, therefore, is to unravel the evolution of zircon Hf isotopes in rocks that were formed deep in the Earth?s crust, and more specifically, to apply these isotopic methods to rocks collected in Dronning Maud Land (DML), East Antarctica. Dronning Maud Land (DML) occupied a central location during the formation of supercontinents ? large landmasses made up of all the continents that exist today - more than 500 million years ago. It is currently thought that supercontinents were formed and dismembered five or six times throughout Earth?s history. The area of DML is key for understanding the formation history of the last two supercontinents. The boundaries of continents that were merged to form those supercontinents are most likely hidden in DML. In this study, the isotopic composition of zircon grains recovered from DML rocks will be employed to identify these boundaries across an extensive section through the area. The rock samples were collected by the investigator during a two-month expedition to Antarctica in the austral summer of 2007?2008. The results of dating and isotope analyses of zircon of the different DML crustal domains will deliver significant insight into the regional geology of East Antarctica and its previous northern extension into Africa. This has significance for the reconstruction of the supercontinents and defining the continental boundaries in DML.
Antarctic coastal polynas are, at the same time, sea-ice free sites and 'sea-ice factories'. They are open water surface locations where water mass transformation and densification occurs, and where atmospheric exchanges with the deep ocean circulation are established. Various models of the formation and persistence of these productive and diverse ocean ecosystems are hampered by the relative lack of in situ meteorological and physical oceanographic observations, especially during the inhospitable conditions of their formation and activity during the polar night. Characterization of the lower atmosphere properties, air-sea surface heat fluxes and corresponding ocean hydrographic profiles of Antarctic polynyas, especially during strong wind events, is sought for a more detailed understanding of the role of polynyas in the production of latent-heat type sea ice and the formation, through sea ice brine rejection, of dense ocean bottom waters A key technological innovation in this work continues to be the use of instrumented unmanned aircraft systems (UAS), to enable the persistent and safe observation of the interaction of light and strong katabatic wind fields, and mesocale cyclones in the Terra Nova Bay (Victoria Land, Antarctica) polynya waters during late winter and early summer time frames.
Abstract Researchers will explore the use of a distributed temperature sensing monitoring system (DTS), using fiber-optical (FO) technology, as the basis of a sustainable, sub-ice cavity sensing array. FO cable systems, such as may be deployed through a hot-water drilled hole through an ice shelf, passing through the underlying cavity to the sea floor, are capable of measuring temperatures down fiber at 1 meter intervals, and at time frequencies as high as 15 seconds. DTS FO systems operate via optical time domain reflectometry along the fiber waveguide using inelastic backscatter of coherent laser light as a probe beam in the FO environment. The introduction of new technologies to the harsh environmental conditions of the Antarctic are often associated with high risk. However, the potential rewards of this approach (e.g. multiyear capability, minimal submerged mechanical or electrical components that may fail, relative simplicity of deployment and measurement principle, yet yielding distributed real time and spatial observation) are attractive enough to conduct a pilot project at a field-ready location (McMurdo). Current indications are that the instability of some of the world's largest ice sheets located around the Antarctic and Greenland may be caused by the presence of warming, deep ocean waters, shoaling over continental shelves, and melting the underside of floating ice shelves. Additional knowledge of the temporal and spatial variability of the temperature fields underneath terminal ice shelves, such as those draining the West Antarctic Ice Sheet, are needed to accurately project future global climate effects on ice-shelf ocean interactions, and in order to inform societal and technological aspects of adaption to changing sea-level.
The stability of the marine West Antarctic Ice Sheet (WAIS) remains an important, unresolved problem for predicting future sea level change. Recent studies indicate that the mass balance of the ice sheet today may be negative or positive. The apparent differences may stem in part from short-term fluctuations in flow. By comparison, geologic observations provide evidence of behavior over much longer time scales. Recent work involving glacial-geologic mapping, dating and ice-penetrating radar surveys suggests that deglaciation of both the Ross Sea Embayment and coastal Marie Byrd Land continued into the late Holocene, and leaves open the possibility of ongoing deglaciation and grounding-line retreat. However, previous work in the Ross Sea Embayment was based on data from just three locations that are all far to the north of the present grounding line. Additional data from farther south in the Ross Sea Embayment are needed to investigate whether recession has ended, or if the rate and pattern of deglaciation inferred from our previous study still apply to the present grounding line. This award provides support to reconstruct the evolution of Reedy Glacier, in the southern Transantarctic Mountains, since the Last Glacial Maximum (LGM). Because Reedy Glacier emerges from the mountains above the grounding line, its surface slope and elevation should record changes in thickness of grounded ice in the Ross Sea up to the present day. The deglaciation chronology of Reedy Glacier therefore can indicate whether Holocene retreat of the WAIS ended thousands of years ago, or is still continuing at present. This integrated glaciologic, glacial-geologic, and cosmogenic-isotope exposure- dating project will reconstruct past levels of Reedy Glacier. Over two field seasons, moraines will be mapped, dated and correlated at sites along the length of the glacier. Radar and GPS measurements will be made to supplement existing ice thickness and velocity data, which are needed as input for a model of glacier dynamics. The model will be used to relate geologic measurements to the grounding-line position downstream. Ultimately, the mapping, dating and ice-modeling components of the study will be integrated into a reconstruction that defines changes in ice thickness in the southern Ross Sea since the LGM, and relates these changes to the history of grounding-line retreat. This work directly addresses key goals of the West Antarctic Ice Sheet Initiative, which are to understand the dynamics, recent history and possible future behavior of the West Antarctic Ice Sheet.
This project constructs POLENET a network of GPS and seismic stations in West Antarctica to understand how the mass of the West Antarctic ice sheet (WAIS) changes with time. The information is ultimately used to predict sea level rise accompanying global warming and interpret climate change records. The GPS (global positioning system) stations measure vertical and horizontal movements of bedrock, while the seismic stations characterize physical properties of the ice/rock interface, lithosphere, and mantle. Combined with satellite data, this project offers a more complete picture of the ice sheet's current state, its likely change in the near future, and its overall size during the last glacial maximum. This data will also be used to infer sub-ice sheet geology and the terrestrial heat flux, critical inputs to models of glacier movement. As well, this project improves tomographic models of the earth's deep interior and core through its location in the Earth's poorly instrumented southern hemisphere. <br/><br/><br/><br/>Broader impacts of this project are varied. The work is relevant to society for improving our understanding of the impacts of global warming on sea level rise. It also supports education at the postdoctoral, graduate, and undergraduate levels, and outreach to groups underrepresented in the sciences. As an International Polar Year contribution, this project establishes a legacy of infrastructure for polar measurements. It also involves an international collaboration of twenty four countries. For more information see IPY Project #185 at IPY.org. NSF is supporting a complementary Arctic POLENET array being constructed in Greenland under NSF Award #0632320.
The investigators propose to build and test a multi-sensor, automated measurement station for monitoring Arctic and Antarctic ice-ocean environments. The system, based on a previously successful design, will incorporate weather and climate sensors, camera, snow and firn sensors, instruments to measure ice motion, ice and ocean thermal profilers, hydrophone, and salinity sensors. This new system will have two-way communications for real-time data delivery and is designed for rapid deployment by a small field group. AMIGOS-II will be capable of providing real time information on geophysical processes such as weather, snowmelt, ice motion and strain, fractures and melt ponds, firn thermal profiling, and ocean conditions from multiple levels every few hours for 2-4 years. Project personnel will conduct a field test of the new system at a location with a deep ice-covered lake. Development of AMIGOS-II is motivated by recent calls by the U.S. Antarctic Program Blue-Ribbon Panel to increase Antarctic logistical effectiveness, which cites a need for greater efficiency in logistical operations. Installation of autonomous stations with reduced logistical requirements advances this goal.
This award supports a program of ground-based geophysical measurements to map in detail the spatial variations of ice flow, accumulation rate, internal layering and ice thickness at the sites which have been identified as promising locations to drill the next deep ice core in West Antarctica. The main investigative tools are a high- and low-frequency ice penetrating radar to image the topography of internal layers and the bed, repeat GPS surveys to calculate the present day surface velocity field, synthetic aperture radar (SAR) interferometry to calculate the regional velocity field, and short firn cores to calculate present day accumulation rates. The data which will be collected will be used to as input to time-dependent ice flow and temperature models that will predict depth variation of age, layer thickness, and temperature. As well as yielding an estimate of expected conditions before drilling, the mismatch between the model prediction and data eventually recovered from the core will help infer thinning and climate (accumulation and temperature) histories for the region. The Western Divide, between the Ross Sea Embayment and the Amundsen Sea, has been identified as the region which best satisfies the criteria which have been established for a deep drilling site. Preliminary site selection using airborne geophysical methods has identified several potential drill sites on the Western Divide where the climate record should be best preserved. This work will contribute in a major way to the final site selection for the next deep ice core in West Antarctica.
The relatively pristine Antarctic continent with its extensive maritime zone represents a unique location on the planet to investigate the long distance aerial transport and deposition of marine microorganisms. The vast extent of new sea ice that forms each winter around the continent results in large numbers of frost flowers, delicate ice-crystal structures of high salt content that form on the surface of the ice and are readily dispersed by wind. The proposed research builds on earlier work in the Arctic and tests the new hypothesis that wind-borne frost flowers provide an effective mechanism for the transport of marine bacteria over long distances, one that can be uniquely sourced and tracked by the frost flower salt signature in the Antarctic realm. A highly resolved genomic snapshot of the microbial community will be acquired at each stage in the transport path, which will track decreasing fractions of the marine microbial community as it freezes into sea ice, incorporates into frost flowers, converts to aerosols, and ultimately deposits within continental snowpack. En route from sea ice to snowpack, marine bacteria will be exposed to an array of environmental stresses, including high salinity, low temperatures, UV light and potential desiccation. A parallel proteomic analysis will enable an evaluation of the microbial response to these extreme conditions and potential survival mechanisms that allow persistence or eventual colonization of deposition sites across Antarctica. Current understanding of microbes in the Antarctic atmosphere is based on a limited number of microscopic and culture-based assays and a single report of low-resolution 16S RNA gene sequence analysis. The research will broadly impact understanding of atmospheric microbiology, from source to deposition, and various issues of microbial survival, colonization, endemism, and diversity under extreme conditions. In addition to venues that reach the scientific community, the research team will develop a permanent multi-media and artifact-based exhibit on Antarctic Microbial Transport that will be showcased at Seattle's Pacific Science Center (PSC), which educates nearly a million visitors annually.
Intellectual Merit: Until recently, wetted soils in the Dry Valleys were generally only found adjacent to streams and lakes. Since the warm austral summer of 2002, numerous ?wet spots? have been observed far from shorelines on relatively flat valley floor locations and as downslope fingers of flow on valley walls. The source of the water to wet these soils is unclear, as is the spatial and temporal pattern of occurrence from year to year. Their significance is potentially great as enhanced soil moisture may change the thermodynamics, hydrology, and erosion rate of surface soils, and facilitate transport of materials that had previously been stable. These changes to the soil active layer could significantly modify permafrost and ground ice stability within the Dry Valleys. The PIs seek to investigate these changes to address two competing hypotheses: that the source of water to these ?wet spots? is ground ice melt and that the source of this water is snowmelt. The PIs will document the spatiotemporal dynamics of these wet areas using high frequency remote sensing data from Quickbird and Wordview satellites to document the occurrence, dimensions, and growth of wet spots during the 2010-11 and 2011-12 austral summers. They will test their hypotheses by determining whether wet spots recur in the same locations in each season, and they will compare present to past distribution using archived imagery. They will also determine whether spatial snow accumulation patterns and temporal ablation patterns are coincident with wet spot formation. Broader impacts: One graduate student will be trained on this project. Findings will be reported at scientific meetings and published in peer reviewed journals. They will also develop a teaching module on remote sensing applications to hydrology for the Modular Curriculum for Hydrologic Advancement and an innovative prototype project designed to leverage public participation in mapping wet spots and snow patches across the Dry Valleys through the use of social media and mobile computing applications.
The importance of gelatinous zooplankton in marine systems worldwide is increasing. In Southern Ocean, increasing salp densities could have a detrimental effect on higher predators, including penguins, fur seals, and baleen whales. The proposed research is a methods-develoment project that will improve the capability to indirectly assess abundances and distributions of salps in the Southern Ocean through acoustic surveys. Hydrographic, net tow, and acoustic backscatter data will be collected in the waters surrounding the South Shetland Islands and the Antarctic peninsula, where both krill and salps are found and compete for food. Shipboard experimental manipulations and measurements will lead to improved techniques for assessment of salp biomass acoustically. Experiments will focus on material properties (density and sound speed), size and shape of salps, as well as how these physical properties will vary with the salp's environment, feeding rate, and reproductive status. In the field, volume backscattering data from an acoustic echosounder will be collected at the same locations as the net tows to enable comparison of net and acoustic estimates of salp abundance. A physics-based scattering model for salps will be developed and validated, to determine if multiple acoustic frequencies can be used to discriminate between scattering associated with krill swarms and that from salp blooms. During the same period as the Antarctic field work, a parallel outreach and education study will be undertaken in Long Island, New York examining local gelatinous zooplankton. This study will enable project participants to learn and practice research procedures and methods before traveling to Antarctica; provide a comparison time-series that will be used for educational purposes; and include many more students and teachers in the research project than would be able to participate in the Antarctic field component.
Abstract <br/>This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). <br/><br/>Marine mammals of the Southern Ocean have evolved diverse life history patterns and foraging strategies to accommodate extreme fluctuations in the physical and biological environment. In light of ongoing climate change and the dramatic shifts in the extent and persistence of sea ice in the Ross Sea, it is critical to understand how Weddell seals, Leptonychotes weddellii, a key apex predator, select and utilize foraging habitats. Recent advances in satellite-linked animal-borne conductivity, temperature and depth (CTD) tags make it possible to simultaneously collect data on seal locations, their diving patterns, and the temperature and salinity profiles of the water columns they utilize. In other ecosystems, such data have revealed that marine predators selectively forage in areas where currents and fronts serve to locally concentrate prey resources, and that these conditions are required to sustain populations. Weddell seals will be studied in McMurdo Sound and at Terra Nova Bay, Ross Sea and will provide the first new data on Weddell seal winter diving behavior and habitat use in almost two decades. The relationship between an animal's diving behavior and physical habitat has enormous potential to enhance monitoring studies and to provide insight into how changes in ice conditions (due either to warming or the impact of large icebergs, such as B15) might impact individual time budgets and foraging success. The second thrust of this project is to use the profiles obtained from CTD seal tags to model the physical oceanography of this region. Current mathematical models of physical oceanographic processes in the Southern Ocean are directed at better understanding the role that it plays in global climate processes, and the linkages between physical and biological oceanographic processes. However, these efforts are limited by the scarcity of oceanographic data at high latitudes in the winter months; CTD tags deployed on animals will collect data at sufficient spatial and temporal resolution to improve data density. The project will contribute to two IPY endorsed initiatives: MEOP (Marine Mammals as Explorers of the Ocean Pole to Pole) and CAML (Census of Antarctic Marine Life). In addition, the highly visual nature of the data and analysis lends itself to public and educational display and outreach, particularly as they relate to global climate change, and we have collaborations with undergraduate and graduate training programs, the Seymour Marine Discovery Center, and the ARMADA program to foster these broader impacts.
The west Antarctic Peninsula is warming rapidly, and continuing changes in the thermal regime will likely result in severe consequences for marine fauna, including potential extinction of strongly adapted stenotherms, and invasions from neighboring faunas. Initial impacts of climate change may result in changes in connectivity among populations of the same species. These changes may will be undetectable by direct observation, but may be assessed via genetic connectivity, i.e. differences in allele or haplotype frequencies among populations can be used to infer levels of gene flow. The proposed research will explore the role that the Scotia Arc plays in connecting populations from South America to Antarctica, a corridor identified as a likely entry route for invaders into Antarctica. It also will examine the way in which cryptic species may confound our knowledge of broad-scale distributions, and in doing so, make contributions towards understanding biodiversity and testing the paradigm of circumpolarity in Antarctica. The principal investigator will to collect multi-locus genetic data across 'species' from a broad suite of benthic marine invertebrate phyla, from multiple locations, in order to address hypotheses regarding speciation and connectivity, to estimate demographic population changes, and to identify the underlying processes that drive observed phylogeographic patterns. Comparative phylogeography is a particularly valuable approach because it enables the identification of long-term barriers and refugia common to groups of species and is consequently highly relevant to conservation planning. Moreover, this work will form a valuable baseline for detecting future changes in connectivity. The results of the research will be disseminated through peer-reviewed publications and presentations at conferences. In addition, the project will support the interdisciplinary training of a female graduate student, two undergraduate students, and host additional summer students through the STARS program at SIO, which helps minority students prepare for graduate school. This project will integrate research and education through conducting an interdisciplinary workshop that brings together Earth Science and Biology high school teachers. This workshop aims to assist teachers derive their own curricula uniting plate tectonics, ocean history and evolution, supporting a new high school earth sciences program. Information generated by this project will also directly feed into international efforts to design a series of Marine Protected Areas (MPAs) in Antarctica.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The high elevations of East Antarctica are critical in localizing the initial Cenozoic glaciation and stabilizing it with respect to melting during warm interglacials. However, the geological history for this region and the geophysical mechanism for maintaining the highlands are poorly understood. In 2007-2009, an array of 24 broadband seismographs (named GAMSEIS) was installed across the Gamburtsev Mountains area of the East Antarctic Plateau as part of the Antarctica?s Gamburtsev Province (AGAP) International Polar Year project. The IPY AGAP/GAMSEIS program included plans by other international partners to install seismographs at locations along the flanks of the Gamburtsev Mountains and in other East Antarctic regions. The proposed project will continue operating six of the deployed AGAP/GAMSEIS stations for two more years together with two new broadband seismic stations added to broaden the geographic scope of the array. Most stations will be located at the existing U.S. Autonomous Geophysical Observatories and the USAP fuel cache locations in order to minimize logistical support. This array, combined with seismographs deployed by China and Japan (and possibly Australia, France, and Italy in near future) will provide a sparse but large-scale network of seismometers for the longer-term studies of the crustal and upper mantle structures underneath the East Antarctic Plateau. Continued reliance on students provides a broader impact to this proposed research and firmly grounds this effort in its educational mission.
This award supports a project to fully characterize the microstructure in ice cores, in particular the microstructural locations of impurities, grain orientations and strain gradients. This work will complement the optical observations, electrical conductivity measurement, and precise, detailed measurements of the soluble ion and gas contents that are performed by others. Linking the concentrations of soluble ions and gases, measured to a few parts per billion, to the optically determined annual layer structure and the stable isotope data in ice cores has enabled a great deal to be established about the concentrations and depth/age distributions of particles, trace gases and impurities for several polar ice cores. Ice core studies carried out by several groups contribute immensely to our understanding of paleoclimate and, to our ability to predict future climate change. The work will build on previous measurements and technique development in this area, as well as focusing on new techniques to characterize ice cores. The work will use both scanning electron microscopy (SEM) coupled with X-ray energy dispersive spectroscopy (EDS) and confocal scanning optical microscopy coupled with Raman spectroscopy (RS) to determine the microstructural locations of impurities and correlate this information with depth/age, and impurity type and concentration for several polar ice cores. The Broader Impacts of the proposed work are that knowledge of the location of impurities coupled with the grain orientation (both c- and a-axis) and grain misorientation information will allow paleoclimatologists to better interpret ice core data and other scientists to understand and model the physical and mechanical properties of natural ice sheets. Other Broader Impacts of the work are that the work will be performed and lead to the education of a Ph.D. student. At the end of the project, as well as the knowledge gained from coursework, the graduate student will have experience in ice core specimen preparation and characterization using scanning electron microscopy, x-ray microanalysis, confocal scanning microscopy, Raman spectroscopy and ion chromatography. Results from the research will be published in refereed journals, presented at conferences, and placed on a web page.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The investigators will examine competing hypotheses for the mechanism of extension and creation of the Transantarctic Mountains, and evolution of the thermal regimes of rifted West Antarctica and stable East Antarctica using magnetotelluric (MT) profiles. Surrounded almost entirely by ocean ridges, Antarctica is a special tectonic situation because of the need to make accommodation space for rifting in the Transantarctic region. In the MT method, temporal variations in the Earth's natural electromagnetic field are used as source fields to probe the electrical resistivity structure in the depth range of 1 to 200 km, or more. Geophysical methods, such as MT, are appropriate in Antarctica because of the predominance of thick ice cover over most of the Continent and the difficult operating environment. The proposed effort will consist of approximately 50 sites over a distance approaching 500 km with a 10 km average spacing, oriented normal to the Transantarctic Mountains (TAM), in the Beardmore glacier area. High quality MT soundings will be collected over thick ice sheets using a custom electrode preamp design, updated from previous Antarctic projects. Data acquisition will take place over two field seasons. The primary goals are three-fold: to establish the location of the deeper tectonic transition between East and West Antarctica that may be offset from the physiographic transition at the surface, using deep resistivity structure distinguish between modes of extensional upwelling and magmatism that may be vertically non-uniform, depth and magnitude of quasi-layered deep crustal low resistivity, particularly below West Antarctica, will be used to estimate crustal heat flux into the ice sheet base.
This award supports a project to fully develop the analytical protocols needed to exploit a relatively new technique for the analysis of soluble organic matter in ice core samples. The technique couples Electrospray ionization to high resolution Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS). Sample volume will be reduced and pre-concentration steps will be eliminated. Following method optimization a suite of ice core samples will be studied from several Antarctic and Greenland locations to address several hypothesis driven research questions. Preliminary results show that a vast record of relatively high molecular weight organic material exists in ice core samples and intriguing results from a few samples warrant further investigation. Several important questions related to developing a better understanding of the nature and paleo record of organic matter in ice cores will be addressed. These include developing a better understanding of the origin of nitrogen and sulfur isotopes in pre-industrial vs. modern samples, developing the methods to apply molecular biomarker techniques, routinely used by organic geochemists for sediment analyses, to the analysis of organic matter in ice cores, tracking the level of oxidation of homologous series of compounds and using them as a proxy for atmospheric oxidant levels in the past and determining whether or not high resolution FTICR mass spectral analysis can provide the ice core community with a robust method to analyze organic materials at the molecular level. The intellectual merit of this work is that this analytical method will provide a new understanding of the nature of organic matter in ice, possibly leading to the discovery of multitudes of molecular species indicative of global change processes whose abundances can be compared with other change proxies. The proposed studies are of an exploratory nature and potentially transformative for the field of ice core research and cryobiology. The broader impacts of these studies are that they should provide compelling evidence regarding organic matter sources, atmospheric processing and anthropogenic inputs to polar ice and how these have varied over time. The collaborative work proposed here will partner atmospheric chemistry/polar ice chemistry expertise with organic geochemistry expertise, resulting in significant contributions to both fields of study and significant advances in ice core analysis. Training of both graduate and undergraduate students will be a key component of the project and students will be involved in collaborative research using advanced analytical instrumentation, presentation of research results at national meetings, and will participate in manuscript preparation.
This award will support the participation of US scientists in an international planning workshop devoted to discussions of how to best facilitate and coordinate international efforts for terrestrial system studies at the McMurdo Dry Valleys of Antarctica. To date, various aspects of the different Dry Valley landscape features (lakes, soils, glaciers, streams) and their biota have been studied most intensively by US and New Zealand scientists, but these efforts could significantly improve their explanatory power if they were coordinated so as to reduce redundancy, decrease environmental degradation and, most importantly, produce comparable datasets. Additionally, many of the present environmental management programs are based on the past baseline composition and location of biotic communities. As these communities become rearranged across the valleys in the future there is interest in assessing whether today's management plans are adequate. To efficiently move these research programs forward for the McMurdo Dry Valleys requires a coordinated, interdisciplinary, long-term data monitoring and observation network. The ultimate objectives of the workshop are to: i) identify the optimal, complementary suites of measurements required to assess and address key processes associated with environmental change in Dry Valley ecosystems; ii) develop standards and protocols for gathering the most critical biotic and abiotic measurements associated with the key processes driving environmental change; iii) generate a draft data coordination and development plan that will maximize the utility of these data; iv) assess the effectiveness of current McMurdo Dry Valley ASMA (Antarctic Special Management Area) environmental protection guidelines.
This award supports a project to use two new scanning fluorimeters to map microbial concentrations vs depth in the WAIS Divide ice core as portions of it become available at NICL, and selected portions of the GISP2 ice core for inter-hemispheric comparison. Ground-truth calibrations with microbes in ice show that the instruments are sensitive to a single cell and can scan the full length of a 1-meter core at 300-micron intervals in two minutes. The goals of these studies will be to exploit the discovery that microbes are transported onto ice, in clumps, several times per year and that at rare intervals (not periodically) of ~104 years, a much higher flux, sometimes lasting >1 decade, reaches the ice. From variations ranging from seasonal to millennial to glacial scale in the arrival time distribution of phototrophs, methanogens, and total microbes in the Antarctic and Arctic ice, the investigators will attempt to determine oceanic and terrestrial sources of these microbes and will look for correlations of microbial bursts with dust concentration and temperature proxies. In addition the project will follow up on the discovery that the rare instances of very high microbial flux account for some of the"gas artifacts" in ice cores - isolated spikes of excess CH4 and N2O that have been discarded by others in previous climate studies. The intellectual merit of this project is that it will exploit scanning fluorimetry of microbes as a powerful new tool for studies ranging from meteorology to climatology to biology, especially when combined with mapping of dust, gases, and major element chemistry in ice cores. In 2010-11 the WAIS Divide borehole will be logged with the latest version of the dust logger. The log will provide mm-scale depth resolution of dust concentration and of volcanic ash layers down the entire depth of the borehole. The locations of ash layers in the ice will be determined and chemical analyses of the ash will be analyzed in order to determine provenance. By comparing data from the WAIS Divide borehole with data from other boreholes and with chemical data (obtained by others) on volcanic layers, the researchers will examine the relationship between the timing of volcanic eruptions and abrupt climate change. Results from this project with the scanning fluorimeters and the dust logger could have applications to planetary missions, borehole oceanography, limnology, meteorology, climate, volcanology, and ancient life in ice. A deeper understanding of the causes of abrupt climate change, including a causal relationship with volcanic explosivity, would enable a better understanding of the adverse effects on climate. The broader impact of the project is that it will provide training to students and post-docs from the U. S. and other countries.
Catania 0739654<br/><br/>This award supports a project to study the Amundsen Sea drainage system and improve understanding of the impact of recent glaciological changes as an aid to predicting how this region will change in the future. The intellectual merit of the work is that the Amundsen Sea drainage system has been a recent focus for glaciological research because of rapid changes occurring there as a result of grounding line retreat. The work will focus on the regions of flow transition and will map the internal stratigraphy of the ice sheet across the Thwaites Glacier shear margins and use the age and geometry of radar-detected internal layers to interpret ice flow history. Thwaites Glacier (one of the main pathways for ice drainage in the region) has recently widened and may continue to do so in the near future. Thwaites Glacier may be particularly vulnerable to grounding line retreat because it lacks a well-defined subglacial channel. The subglacial environment exerts strong control on ice flow and flow history will be mapped in the context of bed topography and bed reflectivity. The plan is to use existing ice-penetrating radar data and coordinate with planned upcoming surveys to reduce logistical costs. The work proposed here will take three years to complete but no additional fieldwork in Antarctica is required. More detailed ground-based geophysical (radar and seismic) experiments will be needed at key locations to achieve our overall goal and the work proposed here will aid in identifying those regions. The broader impacts of the project are that it will initiate a new collaboration among radar communities within the US including those that are on the forefront of radar systems engineering and those that are actively involved in radar-derived internal layer and bed analysis. The project will also provide support for a postdoctoral researcher and a graduate student, thus giving them exposure to a variety of methodologies and scientific issues. Finally, there are plans to further develop the "Wired Antarctica" website designed by Ginny Catania with the help of a student-teacher. This will allow for the existing lesson plans to be updated to Texas State standards so that they can be used more broadly within state middle and high schools.
This award supports analyses of stable isotopes of water, dD, d18O and deuterium excess in the proposed West Antarctic Ice Sheet Divide (WAIS) deep ice core. The project will produce a continuous and high-resolution reconstruction of stable isotope ratios for the new core. dD and d18O values provide estimates of temperature change at the ice core site. Deuterium excess provides estimates of ocean surface conditions, such as sea surface temperature, at the moisture source areas. This new ice core is ideally situated to address questions ranging from ice sheet stability to abrupt climate change. WAIS Divide has high enough snowfall rates to record climate changes on annual to decadal time scales. It should also have ice old enough to capture the last interglacial period in detail. The West Antarctic ice sheet is the subject of great scrutiny as our modern climate warms and sea level rises. What are the prospects for added sea level rise from ice released by this ice sheet? Understanding how this ice sheet has responded to climate change in the past, which the data collected in this project will help to assess, is critical to answering this question. The high temporal resolution available in the WAIS Divide core will provide the best available basis for inter-comparison of millennial-scale climate changes between the poles, and thus a better understanding of the spatial expression and dynamics of rapid climate change events. Finally, the location of this core in the Pacific sector of West Antarctica makes it well situated for examining the influence of the tropical Pacific on Antarctica climate, on longer timescales than are available from the instrumental climate record. Analyses will include the measurement of sub-annually resolved isotope variations in the uppermost parts of the core, measurements at annual resolution throughout the last 10,000 years and during periods of rapid climate change prior to that, and measurements at 50-year resolution throughout the entire length of the core that is collected and processed during the period of this grant. We anticipate that this will be about half of the full core expected to be drilled. In terms of broader impacts, the PIs will share the advising of two graduate students, who will make this ice core the focus of their thesis projects. It will be done in an innovative multi-campus approach designed to foster a broader educational experience. As noted above, the data and interpretations generated by this proposal will address climate change questions not only of direct and immediate scientific interest, but also of direct and immediate policy interest.
This award supports a project to strengthen collaborations between the various research groups working on iceberg calving. Relatively little is known about the calving process, especially the physics that governs the initiation and propagation of fractures within the ice. This knowledge gap exists in part because of the diverse range in spatial and temporal scales associated with calving (ranging from less than one meter to over a hundred kilometers in length scale). It is becoming increasingly clear that to predict the future behavior of the Antarctic Ice Sheet and its contribution to sea level rise, it is necessary to improve our understanding of iceberg calving processes. Further challenges stem from difficulties in monitoring and quantifying short-time and spatial-scale processes associated with ice fracture, including increased fracturing events in ice shelves or outlet glaciers that may be a precursor to disintegration, retreat or increased calving rates. Coupled, these fundamental problems currently prohibit the inclusion of iceberg calving into numerical ice sheet models and hinder our ability to accurately forecast changes in sea level in response to climate change. Seismic data from four markedly different environmental regimes forms the basis of the proposed research, and researchers most familiar with the datasets will perform all analyses. Extracting the similarities and differences across the full breadth of calving processes embodies the core of the proposed work, combining and improving methods previously developed by each group. Techniques derived from solid Earth seismology, including waveform cross-correlation and clustering will be applied to each data set allowing quantitative process comparisons on a significantly higher level than previously possible. This project will derive catalogues of glaciologically produced seismic events; the events will then be located and categorized based on their location, waveform and waveform spectra both within individual environments and between regions. The intellectual merit of this work is that it will lead to a better understanding of iceberg calving and the teleconnections between seismic events and other geophysical processes around the globe. The broader impacts of this work are that it relates directly to socio-environmental impacts of global change and sea level rise. Strong collaborations will form as a result of this research, including bolstered collaborations between the glacier and ice sheet communities, as well as the glaciology and seismology communities. Outreach and public dissemination of findings will be driven by SIO's Visualization Center, and Birch Aquarium, hosting presentations devoted to the role of the cryosphere in global change. Time-lapse movies of recent changes at Columbia Glacier will be used to engage potential young scientists. A program of presentations outside the university setting to at-risk and gifted youth will be continued. This study will also involve undergraduates in analyses and interpretation and presentation of the seismic data assembled. The work will also support two junior scientists who will be supported by this project.
This study will investigate how the Antarctic Slope Front and continental slope morphology determine the exchanges of mass, heat, and fresh water between the shelf and the deep ocean, in particular those leading to outflows of dense water into intermediate and deep layers of the adjacent basins and into the world ocean circulation <br/>While the importance to the global ocean circulation and climate of cold water masses originating in the Antarctic is unquestioned, the processes by which these water masses enter the deep ocean circulation are not. The primary goal of this work therefore is to identify the principal physical processes that govern the transfer of shelf-modified dense water into intermediate and deep layers of the adjacent deep ocean. At the same time, it seeks to understand the compensatory poleward flow of waters from the oceanic regime. The upper continental slope has been identified as the critical gateway for the exchange of shelf and deep ocean waters. Here the topography, velocity and density fields associated with the nearly ubiquitous front must strongly influence the advective and turbulent transfer of water properties between the shelf and oceanic regimes. The study has four specific objectives: [1] Determine the mean frontal structure and the principal scales of variability, and estimate the role of the front on cross-slope exchanges and mixing of adjacent water masses; [2] Determine the influence of slope topography and bathymetry on frontal location and outflow of dense Shelf Water; [3] Establish the role of frontal instabilities, benthic boundary layer transports, tides and other oscillatory processes on cross-slope advection and fluxes; and [4] Assess the effect of diapycnal mixing, lateral mixing identified through intrusions, and nonlinearities in the equation of state on the rate of descent and the fate of outflowing, near-freezing Shelf Water.
Whillans, Wilson, Goad OPP 9527571 Abstract This award supports a project to initiate Global Positioning System (GPS) measurements for rock motions in South Victoria Land and vicinity. The results will be used to test some of the leading models for ice-sheet change and tectonism, in particular, whether the continent is rebounding due to reduced ice load from East or West Antarctica and whether there is tectonic motion due to Terror Rift or uplift of the Transantarctic Mountains. A modest program to measure ice motion will be conducted as well. The motive is to test models for ice flow in the Allan Hills meteorite concentration region and to determine whether small glaciers in the Dry Valleys are thickening or thinning. Monuments will be set into rock and ice and GPS receivers used to determine their locations. Repeats in later years will determine motion. Field activities will involve close cooperation with the USGS.
Winckler/0636898<br/><br/>This award supports a project to study dust sources in Antarctic ice cores. Atmospheric aerosols play an important role both in global biogeochemical cycles as well as in the climate system of the Earth. Records extracted from Antarctic ice cores inform us that dust deposition from the atmosphere to the ice sheet was 15-20 times greater during glacial periods than during interglacials, which raises the possibility that dust may be a key player in climate change on glacial-interglacial timescales. By characterizing potential source areas from South America, South Africa, and Australia as well as fresh glacial flour from Patagonia, the project will determine if the interglacial dust was mobilized from a distinct geographical region (e.g., Australia) or from a more heavily weathered source region in South America. The intellectual merit of the project is that it will contribute to reconstructing climate-related changes in the rate of dust deposition, and in the provenance of the dust, it will provide critical constraints on hydrology and vegetation in the source regions, as well as on the nature of the atmospheric circulation transporting dust to the archive location. In a recent pilot study it was found that there is a dramatic glacial to Holocene change in the 4He/Ca ratio in the dust extracted from ice from Dronning Maud Land, Antarctica, indicating a shift in the source of dust transported to Antarctica. The broader impacts of the project are that Helium isotopes and calcium measurements provide a wealth of information that can then be turned into critical input for dust-climate models. Improved models, which are able to accurately reconstruct paleo dust distribution, will help us to predict changes in dust in response to future climate variability. This information will contribute to an improvement of our integrated understanding of the Earth's climate system and, in turn, will better inform policy makers of those processes and conditions most susceptible to perturbation by climate change, thereby leading to more meaningful climate-change policy. The project will support a graduate student in the dual masters Earth and Environmental Science Journalism program. The lead-PI manages the rock noble gas laboratory at Lamont. Her leadership role in this facility impacts the training of undergraduate and graduate students as well as visiting scientists.
Ice sheet models of the Last Glacial Maximum, and previous glaciation events in the Miocene, suggest that current low altitude, ice-free surfaces in Antarctica were completely covered with ice. If so, the terrestrial biota of Antarctica today would result from recolonization events after each glacial maximum. However, there is emerging evidence that much of the terrestrial Antarctic biota are of ancient origin and have somehow survived these glaciation events. The Transantarctic Mountains TRANsition Zone (TAM-TRANZ) plays a pivotal role in understanding the evolution and biogeographic history of today's Antarctic terrestrial biota, primarily because it contains numerous inland areas that could have served as refugia during glacial maxima. Due to its remote location, the TAM-TRANZ has not been systematically surveyed for animal biodiversity. Although an exhaustive survey of the region requires a multi-discipline, multi-year and multi-region effort, the research herein combines ecological, evolutionary and geophysical expertise to conduct an exploratory investigation of the extreme southern limits of biotic communities. The project will examine the historical geophysical requirements for the colonization and maintenance of functional ecosystems by multicellular organisms, and the feasibility and desirability to implement more systematic biogeographic studies in the future. Broader impacts include graduate and undergraduate student ownership of important subprojects that will provide research, presentation and publication opportunities. The investigators also will contribute to ongoing public education efforts through relationships with K-12 teachers and administrators in the public school districts where the project personnel reside. Finally, the project is leveraged by opportunistic collaboration with scientists associated with Antarctica New Zealand.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The project will employ a sophisticated meteor radar at the Brazilian Antarctic station Comandante Ferraz on King George Island for a number of synergetic research efforts of high interest to the international aeronomical community. The location of the radar will be at the tip of the Antarctic Peninsula - at a critical southern latitude of 62 degrees - to fill a current measurement gap from 54 to 68 degrees south. The radar will play a key role in Antarctic and inter-hemispheric studies of neutral atmosphere dynamics, defining global mesosphere and lower thermosphere structure and variability (from 80 to 105 km) and guiding advances of models accounting for the dynamics of this high-altitude region, including general circulation models, and climate and numerical weather prediction models. The unique radar measurement sensitivity will enable studies of: (1) the large-scale circulation and planetary waves, (2) the tidal structure and variability, (3) the momentum transport by small-scale gravity waves, (4) important, but unquantified, gravity wave - tidal interactions, (5) polar mesosphere summer echoes, and (6) meteor fluxes, head echoes, and non-specular trails, a number of which exhibit high latitudinal gradients at these latitudes. This radar will support extensive collaborations with U.S. and other scientists making measurements at other Antarctic and Arctic conjugate sites, including Brazilian scientists at C. Ferraz and U.S. and international colleagues having other instrumentation in the Antarctic, Arctic, and within South America. Links to the University of Colorado in the U.S., Instituto Nacional de Pesquisas Espaciais (INPE) in Brazil and Universidad Nacional de La Plata in Argentina will provide unique research opportunities for graduate and undergraduate students in the U.S. and South America.
Tulaczyk/0636970<br/><br/>This award supports a project to study elevation change anomalies (henceforth ECAs), which are oval-shaped, 5-to-10 km areas observed in remote sensing images in several locations within the Ross Sea sector of the West Antarctic Ice Sheet (WAIS). Within these anomalies, surface elevation changes at rates of up to ~1 to ~2 cm per day, significantly faster than in surrounding regions. These anomalies are thought to result from filling and draining of multi-kilometer-scale subglacial water pockets. The intellectual merit of this project is that these ECA's represent an unprecedented window into the elusive world of water drainage dynamics beneath the modern Antarctic ice sheet. Although subglacial water fluxes are small compared to normal terrestrial conditions, they play an important role in controlling fast ice streaming and, potentially, stability of the ice sheet. The dearth of observational constraints on sub-ice sheet water dynamics represents one of the most important limitations on progress in quantitative modeling of ice streams and ice sheets. Such models are necessary to assess future ice sheet mass balance and to reconstruct the response of ice sheets to past climate changes. The dynamic sub-ice sheet water transport indicated by the ECAs may have also implications for studies of subglacial lakes and other subglacial environments, which may harbor life adapted to such extreme conditions. The broader impacts of this project are that it will provide advanced training opportunities to one postdoctoral fellow (UW), two female doctoral students (UCSC), who will enhance diversity in polar sciences, and at least three undergraduate students (UCSC). Project output will be relevant to broad scientific and societal interests, such as the future global sea level changes and the response of Polar Regions to climate changes. Douglas Fox, a freelance science journalist, is interested in joining the first field season to write feature articles to popular science magazines and promote the exposure of this project, and Antarctic Science in general, to mass media.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The proposal seeks funds to continue a follow-up analytical work of deep-sea corals collected in the Drake Passage during a research cruise. The project's goal is paleo-climate research looking to constrain the depth structure and time evolution of the radiocarbon content of the Southern Ocean during the glacial and deglaciation. Radiocarbon is a versatile tracer of past climate; its radioactive decay provides an internal clock with which to assess the rates of processes, and it can be used to trace the movement of carbon through the Earth's system. It enters the ocean through air-sea gas exchange, so processes that limits this will, therefore, reduce the radiocarbon content of both surface and deep waters. The Southern Ocean is a critical location for exchange of heat and carbon between the deep-ocean and atmospheric reservoirs, and the deep waters formed there fill large volumes of the global deep and intermediate oceans. As strong currents tend to scour away sediments, carbonate preservation is limited, and radiocarbon reservoir ages are poorly constrained, many traditional paleoceanographic techniques become impractical. It is proposed to alleviate these difficulties analyzing the chemical composition of deep-sea coral skeletons. Their aragonitic skeletons can be precisely dated using U-series decay, and when coupled with radiocarbon analyses will allow to calculate the C14/C12 ratio of the past water column.
9909734 Anderson This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research on the glaciomarine geology of the continental shelves of West Antarctica and the Antarctic Peninsula. It is hypothesized that the different glacial systems of the Antarctic Peninsula region have been more responsive to climate change and sea-level rise than either the West Antarctic or East Antarctic ice sheets. This is due mainly to the smaller size of these ice masses and the higher latitude location of the peninsula. Indeed, ice shelves of the Antarctic Peninsula are currently retreating at rates of up to a kilometer per year. But are these changes due to recent atmospheric warming in the region or are they simply the final phase of retreat since the last glacial maximum? This project hypothesizes that the deglacial history of the Antarctic Peninsula region has been quite complex, with different glacial systems retreating at different rates and at different times. This complex recessional history reflects the different sizes as well as different climatic and physiographic settings of glacial systems in the region. An understanding of the Late Pleistocene to Holocene glacial history of the Antarctic Peninsula glacial systems is needed to address how these systems responded to sea-level and climate change during that time interval. This investigation acquire new marine geological and geophysical data from the continental shelf to determine if and when different glacial systems were grounded on the shelf, to establish the extent of grounded ice, and to examine the history of glacial retreat. The project will build on an extensive seismic data set and hundreds of sediment cores collected along the Peninsula during earlier (1980's) cruises. Key to this investigation is the acquisition of swath bathymetry, side-scan sonar and very high-resolution sub-bottom (chirp) profiles from key drainage outlets. These new data will provide the necessary geomorphologic and stratigraphic framework for reconstructing the Antarctic Peninsula glacial record. Anticipated results will help constrain models for future glacier and ice sheet activity.
IPY: Shedding dynamic light on iron limitation: The interplay of iron<br/>limitation and dynamic irradiance in governing the phytoplankton<br/>distribution in the Ross Sea<br/><br/>The Southern Ocean plays an important role in the global carbon cycle, accounting for approximately 25% of total anthropogenic CO2 uptake by the oceans, mainly via primary production. In the Ross Sea, primary production is dominated by two taxa that are distinct in location and timing. Diatoms dominate in the shallow mixed layer of the continental shelf, whereas the colony forming Phaeocystis antarctica (Prymnesiophyceae) dominate in the more deeply mixed, open regions. Significantly, both groups have vastly different nutrient utilization characteristics, and support very different marine food webs. Their responses to climate change, and the implications for carbon export, are unclear. Previous studies show that light availability and the quality of the light climate (static versus dynamic) play a major role in defining where and when the different phytoplankton taxa bloom. However, iron (Fe) limitation of the algal communities in both the sub-Arctic and the Southern Ocean is now well documented. Moreover, phytoplankton Fe demand varies as a function of irradiance. The main hypothesis of the proposed research is: The interaction between Fe limitation and dynamic irradiance governs phytoplankton distributions in the Ross Sea. Our strategy to test this hypothesis is three-fold: 1) The photoacclimation of the different phytoplankton taxa to different light conditions under Fe limitation will be investigated in experiments in the laboratory under controlled Fe conditions. 2) The photophysiological mechanisms found in these laboratory experiments will then be tested in the field on two cruises with international IPY partners. 3) Finally, data generated during the lab and field parts of the project will be used to parameterize a dynamic light component of the Coupled Ice Atmosphere and Ocean (CIAO) model of the Ross Sea. Using the improved model, we will run future climate scenarios to test the impact of climate change on the phytoplankton community structure, distribution, primary production and carbon export in the Southern Ocean. The proposed research complies with IPY theme" Understanding Environmental change in Polar Regions" and includes participation in an international cruise. Detailed model descriptions and all of the results generated from these studies will be made public via a DynaLiFe website. Improving the CIAO model will give us and other IPY partners the opportunity to test the ecological consequences of physiological characteristics observed in Antarctic phytoplankton under current and future climate scenarios. Outreach will include participation in Stanford's Summer Program for Professional Development for Science Teachers, Stanford's School of Earth Sciences high school internship program, and development of curriculum for local science training centers, including the Chabot Space and Science Center.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The overall goal of this project is to increase understanding of the conjugate nature of the polar ionospheres, which in part helps understanding the multi-scale global solar wind, magnetosphere, and ionosphere system. The project utilizes numerous types of ionospheric remote sensing instrumentation, including: terrestrial GPS receivers, GPS satellite occultation receivers, all-sky imagers, riometers, and magnetometers currently deployed in the Arctic and Antarctic to estimate the 3-D time histories of the ionospheric electron density and also to estimate the polar wind in these polar regions. Furthermore, additional GPS instrumentation will be deployed in Antarctica to increase the number and improve the spatial distribution of GPS receivers in this region. Import aspects of this investigation are: (1) utilization of a large array of instrumentation in the Arctic and Antarctic regions to provide the maximum number of measurements of the ionosphere, (2) the modification and deployment of commercial-off-the-shelf GPS receivers in remote Antarctic locations to improve spatial distribution of GPS measurements, (3) development of a new estimation algorithm for estimating the polar wind, and (4) estimation of 3-D electron density time histories and conductances in conjugate polar ionospheres. The fieldwork and analysis efforts associated with this project are highly suitable for involvement and research training of graduate and undergraduate students.
0538494<br/>Meese<br/>This award supports a project for physical properties research on snow pits and firn/ice cores with specific objectives that include stratigraphic analysis including determination of accumulation rates, annual layers, depth hoar, ice and wind crusts and rates of grain growth with depth. Studies of firn densification rates and how these parameters relate to the meteorology and climatology over the last 200 years of snow accumulation in Antarctica will also be investigated. The project will also determine the seasonality of accumulation by co-registration of stratigraphy and chemistry and determination of chemical species at the grain boundaries, how these may change with depth/densification (and therefore temperature), precipitation, and may affect grain growth. Fabric analyses will be made, including variation with depth, location on undulations and if any variation exists with climate/chemistry. The large spatial coverage of the US ITASE program offers the opportunity to determine how these parameters are affected by a large range of temperature, precipitation and topographic effects. The intellectual merit of the project includes the fact that ITASE is the terrestrial equivalent of a polar research vessel that provides a unique, logistically efficient, multi-dimensional (x, y, z and time) view of the atmosphere, ice sheet and their histories. Physical properties measurements/ analyses are an integral part of understanding the dynamic processes to which the accumulated snow is subjected. Recent advancements in the field along with multiple core sites provide an excellent opportunity to gain a much broader understanding of the spatial, temporal and physical variables that impact firnification and the possible resultant impact on climatic interpretation. In terms of broader impacts, the data collected by US ITASE and its international ITASE partners is available to a broad scientific community. US ITASE has an extensive program of public outreach and provides significant opportunities for many students to experience multidisciplinary Antarctic research. A graduate student, a post-doctoral fellow and at least one undergraduate would be funded by this work. Dr. Meese is also a member of the New England Science Collaborative, an organization that educates the public on climate change based on recent scientific advancements.
Antarctic notothenioid fish evolved antifreeze (AF) proteins that prevent ice crystals that enter their body fluids from growing, and thereby avoid freezing in their icy habitats. However, even in the extreme cold Antarctic marine environment, regional gradations of severity are found. The biological correlate for environmental severity in fish is the endogenous ice load, which likely determines the tolerable limit of environmental severity for notothenioid habitation. The endogenous ice load develops from environmental ice crystals entering through body surfaces and somehow localizing to the spleen. How prone the surface tissues are to ice entry, how ice reaches the spleen, and what the fate of splenic ice is, requires elucidation. Spleen sequestration of ice raises the hypothesis that macrophages may play a role in the translocation and perhaps elimination of AF-bound ice crystals. Antifreeze glycoproteins (AFGP) act in concert with a second, recently discovered antifreeze called antifreeze potentiating protein (AFPP), necessitating an assessment of the contribution of AFPP to freezing avoidance. Recent research suggests that the exocrine pancreas and the anterior stomach, not the liver, synthesize AFGPs and secrete them into the intestine, from where they may be returned to the blood. A GI-to-blood transport is a highly unconventional path for a major plasma protein and also begs the questions, What is the source of blood AFPP?. Why are two distinct AF proteins needed and what is the chronology of their evolution? What genomic changes in the DNA are associated with the development or loss of the antifreeze trait? Experiments described in this proposal address these interrelated questions of environmental, organismal, and evolutionary physiology, and will further our understanding of novel vertebrate physiologies, the limits of environmental adaptation, and climatically driven changes in the genome. The proposed research will (1) determine the temporal and spatial heterogeneity of environmental temperature and iciness in progressively more severe fish habitats in the greater McMurdo Sound area, and in the milder Arthur Harbor at Palmer Station. The splenic ice load in fishes inhabiting these sites will be determined to correlate to environmental severity and habitability. (2) Assess the surface tissue site of ice entry and their relative barrier properties in intact fish and isolated tissues preparations (3) Assess the role of immune cells in the fate of endogenous ice, (4) determine whether the blood AFGPs are from intestinal/rectal uptake, (5) examine the contribution of AFPP to the total blood AF activity (6) evaluate the progression of genomic changes in the AFGP locus across Notothenioidei as modulated by disparate thermal environments, in four selected species through the analyses of large insert DNA BAC clones. The origin and evolution of AFPP will be examined also by analyzing BAC clones encompassing the AFPP genomic locus. The broader impacts of the proposed research include training of graduate and undergraduate students in research approaches ranging from physical field measurements to cutting edge genomics. Undergraduate research projects have lead to co-authored publications and will continue to do so. Outreach includes establishing Wiki websites on topics of Antarctic fish biology and freeze avoidance, providing advisory services to the San Francisco Science Exploratorium, and making BAC libraries available to interested polar biologists. This research theme has repeatedly received national and international science news coverage and will continue to be disseminated to the public in that manner.
Salps are planktonic grazers that have a life history, feeding biology and population dynamic strikingly different from krill, copepods or other crustacean zooplankton. Salps can occur in very dense population blooms that cover large areas and have been shown to have major impacts due to the their grazing and the production of fast-sinking fecal pellets. Although commonly acknowledged as a major component of the Southern Ocean zooplankton community, often comparable in biomass and distribution to krill, salps have received relatively little attention. Although extensive sampling has documented the seasonal abundance of salps in the Southern Ocean, there is a paucity of data on important rates that determine population growth and the role of this species in grazing and vertical flux of particulates. This proposed study will include: measurements of respiration and excretion rates for solitary and aggregate salps of all sizes; measurements of ingestion rates, including experiments to determine the size or concentration of particulates that can reduce ingestion; and determination of growth rates of solitaries and aggregates. In addition to the various rate measurements, this study will include quantitative surveys of salp horizontal and vertical distribution to determine their biomass and spatial distribution, and to allow a regional assessment of their effects. Measurements of the physical characteristics of the water column and the quantity and quality of particulate food available for the salps at each location will also be made. Satellite imagery and information on sea-ice cover will be used to test hypotheses about conditions that result in high densities of salps. Results will be used to construct a model of salp population dynamics, and both experimental and modeling results will be interpreted within the context of the physical and nutritional conditions to which the salps are exposed. This integrated approach will provide a good basis for understanding the growth dynamics of salp blooms in the Southern Ocean. Two graduate students will be trained on this project, and cruise and research experience will be provided for two undergraduate students. A portion of a website allowing students to be a virtual participant in the research will be created to strengthen students' quantitative skills. Both PI's will participate in teacher-researcher workshops, and collaboration with a regional aquarium will be developed in support of public education.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a study to investigate the tectonic development of the southwestern Ross Sea region. Displacements between East and West Antarctica have long been proposed based on global plate circuits, apparent hot spot motions, interpretations of seafloor magnetic anomalies, paleomagnetism, and on geologic grounds. Such motions require plate boundaries crossing Antarctica, yet these boundaries have never been explicitly defined. This project will attempt to delineate the late Cenozoic - active boundary between East and West Antarctica along the Terror Rift in the western Ross Sea, where young structures have been identified, continuity between active extension and intracontinental structures can be established, and where accessibility via ship will allow new key data sets to be acquired. We will use multi-source marine and airborne geophysical data to map the fault patterns and volcanic structure along the eastern margin of the Terror Rift. The orientations of volcanic fissures and seamount alignments on the seafloor will be mapped using multibeam bathymetry. The volcanic alignments will show the regional extension or shear directions across the Terror Rift and the orientations of associated crustal stresses. Swath bathymetry and single channel seismic data will be used to document neotectonic fault patterns and the eastern limit of recent faulting. Delineation of neotectonic fault patterns will demonstrate whether the eastern margin of the Terror Rift forms a continuous boundary and whether the rift itself can be linked with postulated strike-slip faults in the northwestern Ross Sea. Seafloor findings from this project will be combined with fault kinematic and stress field determinations from the surrounding volcanic islands and the Transantarctic Mountains. The integrated results will test the propositions that the eastern boundary of the Terror Rift forms the limit of the major, late Cenozoic -active structures through the Ross Sea and that Terror Rift kinematics involve dextral transtension linked to the right-lateral strike-slip faulting to the north. These results will help constrain the kinematic and dynamic links between the West Antarctic rift system and Southern Ocean structures and any related motions between East and West Antarctica. In the first year, a collaborative structural analysis of existing multichannel and single channel seismic profiles and aeromagnetic data over the Terror Rift will be conducted. The location of volcanic vents or fissures and any fault scarps on the sea floor will be identified and a preliminary interpretation of the age and kinematics of deformation in the Terror Rift will be produced. Late in the second year, a one-month cruise on RVIB N.B. Palmer will carry out multibeam bathymetric and sidescan sonar mapping of selected portions of the seafloor of Terror Rift. Gravity, magnetics, seismic reflection and Bathy2000 3.5 kHz sub-bottom profile data will also be collected across the rift. In the third year, we will use these multisource data to map the orientations and forms of volcanic bodies and the extent and geometry of neotectonic faulting associated with the Terror Rift. The project will: 1) complete a map of neotectonic faults and volcanic structures in the Terror Rift; 2) interpret the structural pattern to derive the motions and stresses associated with development of the rift; 3) compare Terror Rift structures with faults and lineaments mapped in the Transantarctic Mountains to improve age constraints on the structures; and 4) integrate the late Cenozoic structural interpretations from the western Ross Sea with Southern Ocean plate boundary kinematics.
This project is a study of the evolution of the sea ice cover, and the mass balance of ice in the Amundsen Sea and the Bellingshausen Sea in the internationally collaborative context of the International Polar Year (2007-2008). In its simplest terms, the mass balance is the net freezing and melting that occurs over an annual cycle at a given location. If the ice were stationary and were completely to melt every year, the mass balance would be zero. While non-zero balances have significance in questions of climate and environmental change, the process itself has global consequences since the seasonal freeze-melt cycle has the effect of distilling the surface water. Oceanic salt is concentrated into brine and rejected from the ice into deeper layers in the freezing process, while during melt, the newly released and relatively fresh water stabilizes the surface layers. The observation program will be carried out during a drift program of the Nathaniel B. Palmer, and through a buoy network established on the sea ice that will make year-long measurements of ice thickness, and temperature profile, large-scale deformation, and other characteristics. The project is a component of the Antarctic Sea Ice Program, endorsed internationally by the Joint Committee for IPY. Additionally, the buoys to be deployed have been endorsed as an IPY contribution to the World Climate Research Program/Scientific Committee on Antarctic Research (WCRP/SCAR) International Programme on Antarctic Buoys (IPAB). While prior survey information has been obtained in this region, seasonal and time-series measurements on sea ice mass balance are crucial data in interpreting the mechanisms of air-ice-ocean interaction. <br/> The network will consist of an array of twelve buoys capable of GPS positioning. Three buoys will be equipped with thermister strings and ice and snow thickness measurement gauges, as well as a barometer. Two buoys will be equipped with meteorological sensors including wind speed and direction, atmospheric pressure, and incoming radiation. Seven additional buoys will have GPS positioning only, and will be deployed approximately 100 km from the central site. These outer buoys will be critical in capturing high frequency motion complementary to satellite-derived ice motion products. Additional buoys have been committed internationally through IPAB and will be deployed in the region as part of this program.<br/> This project will complement similar projects to be carried out in the Weddell Sea by the German Antarctic Program, and around East Antarctica by the Australian Antarctic Program. The combined buoy and satellite deformation measurements, together with the mass balance measurements, will provide a comprehensive annual data set on sea ice thermodynamics and dynamics for comparison with both coupled and high-resolution sea ice models.
This award supports an integrated seismic, sedimentologic, and paleontologic investigation of glacio-marine stratigraphy of the Ross Sea continental shelf. The purpose of this work is to acquire seismic images and sediment cores of the glacial sediments toward a better understanding of the Cenozoic history of glaciation in the Ross Sea region. This investigation will utilize high resolution seismic profiling data to locate regions where the Pleistocene glacial till is thin or perhaps absent. Piston coring at these locations, if the till is penetrated, will provide sedimentary records of Cenozoic depositional environments and could provide important clues to fluctuations of the Antarctic Ice Sheets. The seismic profiling will provide a direct record of the grounding history of the Ross Ice Shelf during the Pleistocene and it will also allow first order correlations of Cenozoic sedimentary units that are represented by sediments recovered in the piston cores. This work will provide important proxy records of the history of both the West Antarctic Ice Sheet and the East Antarctic Ice Sheet and this, in turn, will provide important constraints to climate models.
The potential consequence of human impact on wildlife in Antarctica has been debated for many decades. Scientists, support staff and visitors in Antarctica may have an effect on the behavior and population dynamics of marine mammals and seabirds. Since the early 1970's, shipboard tourism has expanded to the point where it is timely to address the question, using a scientific research approach. The focus of this study is to examine the potential effect of tourist activities on the Adelie Penguins (Pygoscelis adeliae) in the Antarctic Peninsula. The topic has gathered the interest and opinions of those in private industry, the scientific community, government organizations and environmental groups. A key concern is that increases in these activities may eventually overcome the ability of research to address critical issues in a timely and biologically meaningful manner. The approach to understanding how tourism might affect Adelie Penguins must involve both a study of human activity and a study of natural variability in the physical environment. The ongoing Palmer Long Term Ecological Research program focuses on the ecosystem and its components and thus addresses the issues of natural variability. This project focuses on the human dimension and continues a tourist-monitoring program begun as a pilot project near Palmer Station. This site is in a geographic location that mirrors current patterns in tourism and tourist-wildlife interactions in the western Antarctic Peninsula. It also offers a setting that provides unique opportunities for human impacts research. This includes the presence of long-term databases that document environmental variability over multiple time and space scales in both marine and terrestrial habitats, and the ability to examine potential tourist impacts as part of controlled experiments. The results of the study will have important implications to understanding interactions between climate change and ecosystem response, and for detecting, mitigating and managing the consequences of human activities such as tourism.
9731695 Klinkhammer This award supports participation of Oregon State University (OSU) researchers in an expedition of the German oceanographic research vessel POLARSTERN to the Antarctic Ocean (POLARSTERN cruise ANT-XV/2). Previous OSU researchers supported by the US Antarctic Program identified several areas of hydrothermal venting in the Bransfield Strait. This discovery has important implications to the biogeography of vent animals, the geological evolution of ore deposits, and the chemical and heat budgets of the Earth. The previous work sampled water and particles from above the vent sites at a reconnaissance level. Subsequent chemical analyses of these samples provided insight into the chemistry of fluids emanating from vents on the sea floor. The POLARSTERN cruise affords a unique opportunity to build on these discoveries in the Bransfield Strait, foster future international work in the Bransfield area, extend research on hydrothermal activity to other parts of the Antarctic Peninsula region, and develop a working relationship with a strong international group. In particular, the POLARSTERN expedition provides the opportunity for: 1) additional sampling of water and suspended particulate matter in the water column over the Bransfield hydrothermal sites this sampling would be aided by German photographic reconnaissance; 2) reconnaissance, to determine the broader geographical extent of hydrothermal activity, would be extended to the Scotia Arc and trench areas following the general theme of the German program which is fluid expulsion from the Scotia- Bransfield system; and 3) the use of unique tools available on the POLARSTERN such as a camera sled and grab bottom sampler. This work will make it possible to better define the location of hydrothermal vents and to begin to quantify the amount of water being expelled by this hydrothermal activity. If vents can be precisely located, the bottom photography holds the promise of revealing possible biologic al communities associated with these submarine hot springs.
During the past few decades of oceanographic research, it has been recognized that significant variations in biogeochemical processes occur among years. Interannual variations in the Southern Ocean are known to occur in ice extent and concentration, in the composition of herbivore communities, and in bird and marine mammal distributions and reproductive success. However, little is known about the interannual variations in production of phytoplankton or the role that these variations play in the food web. This project will collect time series data on the seasonal production of phytoplankton in the southern Ross Sea, Antarctica. Furthermore, it will assess the interannual variations of the production of the two major functional groups of the system, diatoms and Phaeocystis Antarctica, a colonial haptophyte. The Ross Sea provides a unique setting for this type of investigation for a number of reasons. For example, a de facto time-series has already been initiated in the Ross Sea through the concentration of a number of programs in the past ten years. It also is well known that the species diversity is reduced relative to other systems and its seasonal production is as great as anywhere in the Antarctic. Most importantly, seasonal production of both the total phytoplankton community (as well as its two functional groups) can be estimated from late summer nutrient profiles. The project will involve short cruises on the US Coast Guard ice breakers in the southern Ross Sea that will allow the collection of water column nutrient and particulate after data at specific locations in the late summer of each of five years. Additionally, two moorings with in situ nitrate analyzers moored at fifteen will be deployed, thus collecting for the first time in the in the Antarctic a time-series of euphotic zone nutrient concentrations over the entire growing season. All nutrient data will be used to calculate seasonal production for each year in the southern Ross Sea and compared to previously collected information, thereby providing an assessment of interannual variations in net community production. Particulate matter data will allow us to estimate the amount of export from the surface layer by late summer, and therefore calculate the interannual variability of this ecosystem process. Interannual variations of seasonal production (and of the major taxa of producers) are a potentially significant feature in the growth and survival of higher trophic levels within the food web of the Ross Sea. They are also important in order to understand the natural variability in biogeochemical processes of the region. Because polar regions such as the Ross Sea are predicted to be impacted by future climate change, biological changes are also anticipated. Placing these changes in the context of natural variability is an essential element of understanding and predicting such alterations. This research thus seeks to quantify the natural variability of an Antarctic coastal system, and ultimately understand its causes and impacts on food webs and biogeochemical cycles of the Ross Sea.
This project will utilize the R/VIB Nathaniel B. Palmer's transit cruises to collect marine geophysical data on targets-of-opportunity in the southern oceans. Because the Palmer generally traverses regions only sparsely surveyed with geophysical instruments, this project represents a cost-effective way to collect important new data. The work's focus is expanding our knowledge of plate motion histories for the Antarctic and surrounding plates. The ultimate goals are improving global plate reconstructions and gaining new insight into general plate kinematics and dynamics and lithospheric rheology. Only slight deviations from the straight routes are required, and we expect to operate on one cruise per year over the three years of the project. The first cruise from New Zealand to Chile will survey a flow line of Pacific-Antarctic plate motion along the Menard fracture zone, which crosses the East Pacific Rise at ~50 S latitude. Swath bathymetry, gravity, magnetics, and a small amount of seismic reflection profiling will be collected to determine the exact trace of the fracture zone and its relationship to the associated gravity anomaly seen in shipboard and satellite radar altimetry data. These observations are critical for precise plate reconstructions, and will provide GPS-navigated locations of a major fracture zone near the northern end of the Pacific-Antarctic boundary. These data will be used in combination with similar data from the Pitman fracture zone at the southwestern end of the plate boundary and magnetic anomalies from previous cruises near the Menard fracture zone to improve high-precision plate reconstructions and evaluate the limits of internal deformation of the Pacific and Antarctic plates. The science plan for cruises in following years will be designed once transit schedules are set. In terms of broader impacts, we plan to teach an on-board marine geophysics class to graduate and undergraduate students on two cruises. The class consists of daily classroom lectures about the instruments and data; several hours per day of watch standing and data processing; and work by each student on an independent research project. We expect to accommodate 15 students per class, including participants from primarily undergraduate institutions with high minority enrollments.
The Antarctic Site Inventory Project has collected biological data and site-descriptive information in the Antarctic Peninsula region since 1994. This research effort has provided data on those sites which are visited by tourists on shipboard expeditions in the region. The aim is to obtain data on the population status of several key species of Antarctic seabirds, which might be affected by the cumulative impact resulting from visits to the sites. This project will continue the effort by focusing on two heavily-visited Antarctic Peninsula sites: Paulet Island, in the northwestern Weddell Sea and Petermann Island, in the Lemaire Channel near Anvers Island. These sites were selected because both rank among the ten most visited sites in Antarctica each year in terms of numbers of visitors and zodiac landings; both are diverse in species composition, and both are sensitive to potential environmental disruptions from visitors. These data collected focus on two important biological parameters for penguins and blue-eyed shags: (1) breeding population size (number of occupied nests) and (2) breeding success (number of chicks per occupied nests). A long-term data program will be supported, with studies at the two sites over a five-year period. The main focus will be at Petermann Island, selected for intensive study due to its visitor status and location in the region near Palmer Station. This will allow for comparative data with the Palmer Long Term Ecological Research program. Demographic data will be collected in accordance with Standard Methods established by the Convention for the Conservation of Antarctic Marine Living Resources Ecosystem Monitoring Program and thus will be comparable with similar data sets being collected by other international Antarctic Treaty nation research programs. While separating human-induced change from change resulting from a combination of environmental factors will be difficult, this work will provide a first step to identify potential impacts. These long-term data sets will contribute to a better understanding of biological processes in the entire region and will contribute valuable information to be used by the Antarctic Treaty Parties as they address issues in environmental stewardship in Antarctica.
This award, provided by the Office of Polar Programs of the National Science Foundation, supports research to investigate the seismicity and tectonics of the South Shetland Arc and the Bransfield Strait. This region presents an intriguing and unique tectonic setting, with slowing of subduction, cessation of island arc volcanism, as well as the apparent onset of backarc rifting occurring within the last four million years. This project will carry out a 5-month deployment of 14 ocean bottom seismographs (OBSs) to complement and extend a deployment of 6 broadband land seismic stations that were successfully installed during early 1997. The OBSs include 2 instruments with broadband sensors, and all have flowmeters for measuring and sampling hydrothermal fluids. The OBSs will be used to examine many of the characteristics of the Shetland- Bransfield tectonic system, including: --- The existence and depth of penetration of a Shetland Slab: The existence of a downgoing Shetland slab will be determined from earthquake locations and from seismic tomography. The maximum depth of earthquake activity and the depth of the slab velocity anomaly will constrain the current configuration of the slab, and may help clarify the relationship between the subducting slab and the cessation of arc volcanism. -- Shallow Shetland trench seismicity?: No teleseismic shallow thrust faulting seismicity has been observed along the South Shetland Trench from available seismic information. Using the OBS data, the level of small earthquake activity along the shallow thrust zone will be determined and compared to other regions undergoing slow subduction of young oceanic lithosphere, such as Cascadia, which also generally shows very low levels of thrust zone seismicity. -- Mode of deformation along the Bransfield Rift: The Bransfield backarc has an active rift in the center, but there is considerable evidence for off-rift faulting. There is a long-standing controversy about whet her back-arc extension occurs along discrete rift zones, or is more diffuse geographically. This project will accurately locate small earthquakes to better determine whether Bransfield extension is discrete or diffuse. -- Identification of volcanism and hydrothermal activity: Seismic records will be used to identify the locations of active seafloor volcanism along the Bransfield rift. Flowmeters attached to the OBSs will record and sample the fluid flux out of the sediments. -- Upper mantle structure of the Bransfield - evidence for partial melting?: Other backarc basins show very slow upper mantle seismic velocities and high seismic attenuation, characteristics due to the presence of partially molten material. This project will use seismic tomography to resolve the upper mantle structure of the Bransfield backarc, allowing comparison with other backarc regions and placing constraints on the existence of partially molten material and the importance of partial melting as a mantle process in this region. Collaborative awards: OPP 9725679 and OPP 9726180
Domack: OPP 9615053 Manley: OPP 9615670 Banerjee: OPP 9615695 Dunbar: OPP 9615668 Ishman: OPP 9615669 Leventer: OPP 9714371 Abstract This award supports a multi-disciplinary, multi-institutional effort to elucidate the detailed climate history of the Antarctic Peninsula during the Holocene epoch (the last 10,000 years). The Holocene is an important, but often overlooked, portion of the Antarctic paleoclimatic record because natural variability in Holocene climate on time scales of decades to millennia can be evaluated as a model for our present "interglacial" world. This project builds on over ten years of prior investigation into the depositional processes, productivity patterns and climate regime of the Antarctic Peninsula. This previous work identified key locations that contain ultra-high resolution records of past climatic variation. These data indicate that solar cycles operating on multi-century and millennial time scales are important regulators of meltwater production and paleoproductivity. These marine records can be correlated with ice core records in Greenland and Antarctica. This project will focus on sediment dispersal patterns across the Palmer Deep region. The objective is to understand the present links between the modern climatic and oceanographic systems and sediment distribution. In particular, additional information is needed regarding the influence of sea ice on the distribution of both biogenic and terrigenous sediment distribution. Sediment samples will be collected with a variety of grab sampling and coring devices. Analytical work will include carbon-14 dating of surface sediments using accellerator mass spectrometry and standard sedimentologic, micropaleontologic and magnetic granulometric analyses. This multiparameter approach is the most effective way to extract the paleoclimatic signals contained in the marine sediment cores. Two additional objectives are the deployment of sediment traps in front of the Muller Ice Shelf in Lallemand Fjord and seismic reflection work in conjunction with site augmentation funded through the Joint Oceanographic Institute. The goal of sediment trap work is to address whether sand transport and deposition adjacent to the ice shelf calving line results from meltwater or aeolian processes. In addition, the relationship between sea ice conditions and primary productivity will be investigated. The collection of a short series of seismic lines across the Palmer Deep basins will fully resolve the question of depth to acoustic basement. The combination of investigators on this project, all with many years of experience working in high latitude settings, provides an effective team to complete the project in a timely fashion. A combination of undergraduate, graduate and post-graduate students will be involved in all stages of the project so that educational objectives will be met in-tandem with research goals of the project.
An array of moorings will be deployed and maintained east of Cape Adare, Antarctica, at the northwestern corner of the Ross Sea to observe the properties of Antarctic Bottom Water (AABW) exiting the Ross Sea. This location has been identified from recent studies as an ideal place to make such measurements. Antarctic Bottom Water has the highest density of the major global water masses, and fills the deepest parts of the world's oceans. Because it obtains many of its characteristics during its contact with the atmosphere and with glacial ice along the continental margins of Antarctica, it is expected that changes in newly-formed AABW may represent an effective indicator for abrupt climate change. The heterogeneous nature of the source regions around Antarctica complicates the observation of newly-formed AABW properties. The two most important source regions for AABW are within the Weddell and the Ross Seas, with additional sources drawn from the east Antarctic margins. In the northwestern Weddell Sea, several programs have been undertaken in the last decade to monitor the long term variability of Weddell Sea Deep and Bottom Water, precursors of AABW originating from the Weddell Sea, however no such systematic efforts have yet been undertaken to make longterm measurements of outflow from the Ross Sea. The proposed study will significantly improve our knowledge of the long term variability in the outflow of deep and bottom water from the Ross Sea, and will provide the beginnings of a long-term monitoring effort which ultimately will allow detection of changes in the ocean in the context of global climate change. When joined with similar efforts ongoing in the Weddell Sea, long-term behavior and possible coupling of these two important sources of the ocean's deepest water mass can be examined in detail.
PROPOSAL NO.: 0094078<br/>PRINCIPAL INVESTIGATOR: Bart, Philip<br/>INSTITUTION NAME: Louisiana State University & Agricultural and Mechanical College<br/>TITLE: CAREER: Relative frequency and phase of extreme expansions of the Antarctic Ice Sheets during the late Neogene<br/>NSF RECEIVED DATE: 07/27/2000<br/><br/>PROJECT SUMMARY<br/><br/>Expansions and contractions of the Antarctic Ice Sheets (AISs) have undoubtedly had a profound influence on Earth's climate and global sea-level. However, rather than being a single entity, the Antarctic cryosphere consists of three primary elements: 1) the East Antarctic Ice Sheet (EAIS); 2) the West Antarctic Ice Sheet (WAIS); and 3) the Antarctic Peninsula Ice Cap (APIC). The distinguishing characteristics include significant differences in: 1) ice volume; 2) substratum elevation; 3) ice-surface elevation; and 4) location with respect to latitude. Various lines of evidence indicate that the AISs have undergone significant fluctuations in the past and that fluctuations will continue to occur in the future. The exact nature of the fluctuations has been the subject of many lively debates. According to one line of reasoning, the land-based EAIS has been relatively stable, experiencing only minor fluctuations since forming in the middle Miocene, whereas the marine-based WAIS has been dynamic, waxing and waning frequently since the late Miocene. According to an alternate hypothesis, the ice sheets advanced and retreated synchronously. These two views are incompatible. <br/><br/>The first objective of this proposal is to compare the long-term past behavior of the WAIS to that of the EAIS and APIC. The fluctuations of the AISs involve many aspects (the frequency of changes, the overall magnitude of ice-volume change, etc.), and the activities proposed here specifically concern the frequency and phase of extreme advances of the ice sheet to the continental shelf. The project will build upon previous seismic-stratigraphic investigations of the continental shelves. These studies have clarified many issues concerning the minimum frequency of extreme expansions for the individual ice sheets, but some important questions remain. During the course of the project, the following questions will be evaluated.<br/><br/>Question 1) Were extreme advances of the EAIS and WAIS across the shelf of a similar frequency and coeval? This evaluation is possible because the western Ross Sea continental shelf (Northern Basin) receives drainage from the EAIS, and the eastern Ross Sea (Eastern Basin) receives drainage from the WAIS. Quantitative analyses of the extreme advances from these two areas have been conducted by Alonso et al. (1992) and Bart et al. (2000), respectively. However, the existing single-channel seismic grids are incomplete and can not be used to determine the stratigraphic correlations from Northern Basin to Eastern Basin. It is proposed that high-resolution seismic data (~2000 kms) be acquired to address this issue.<br/><br/>Question 2) Were extreme advances of the APIC across the shelf as frequent as inferred by Bart and Anderson (1995)? Bart and Anderson (1995) inferred that the APIC advanced across the continental shelf at least 30 times since the middle Miocene. This is significant because it suggests that the advances of the small APIC were an order of magnitude more frequent than the advances of the EAIS and WAIS. Others contest the Bart and Anderson (1995) glacial-unconformity interpretation of seismic reflections, and argue that the advances of the APIC were far fewer (i.e., Larter et al., 1997). The recent drilling on the Antarctic Peninsula outer continental shelf has sampled some but not all of the glacial units, but the sediment recovery was poor, and thus, the glacial history interpretation is still ambiguous. The existing high-resolution seismic grids from the Antarctic Peninsula contain only one regional strike line on the outer continental shelf. This is inadequate to address the controversy of the glacial-unconformity interpretation and the regional correlation of the recent ODP results. It is proposed that high-resolution seismic data (~1000 kms) be acquired in a forthcoming (January 2002) cruise to the Antarctic Peninsula to address these issues.<br/><br/>The second objective of this project is 1) to expand the PI's effort to integrate his ongoing and the proposed experiments into a graduate-level course at LSU, and 2) to develop a pilot outreach program with a Baton Rouge public high school. The Louisiana Department of Education has adopted scientific standards that apply to all sciences. These standards reflect what 9th through 12th grade-level students should be able to do and know. The PI will target one of these standards, the Science As Inquiry Standard 1 Benchmark. The PI will endeavor to share with the students the excitement of conducting scientific research as a way to encourage the students to pursue earth science as a field of study at the university level.
Luyendyk et.al.: OPP 0088143<br/>Bartek: OPP 0087392<br/>Diebold: OPP 0087983<br/><br/>This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a collaborative research program in marine geology and geophysics in the southern central and eastern Ross Sea. The project will conduct sites surveys for drilling from the Ross Ice Shelf into the seafloor beneath it. Many of the outstanding problems concerning the evolution of the East and West Antarctic Ice Sheets, Antarctic climate, global sea level, and the tectonic history of the West Antarctic Rift System can be addressed by drilling into the seafloor of the Ross Sea. Climate data for Cretaceous and Early Cenozoic time are lacking for this sector of Antarctica. Climate questions include: Was there any ice in Late Cretaceous time? What was the Antarctic climate during the Paleocene-Eocene global warming? When was the Cenozoic onset of Antarctic glaciation, when did glaciers reach the coast and when did they advance out onto the margin? Was the Ross Sea shelf non-marine in Late Cretaceous time; when did it become marine? Tectonic questions include: What was the timing of the Cretaceous extension in the Ross Sea rift; where was it located? What is the basement composition and structure? Where are the time and space limits of the effects of Adare Trough spreading? Another drilling objective is to sample and date the sedimentary section bounding the mapped RSU6 unconformity in the Eastern Basin and Central Trough to resolve questions about its age and regional extent. Deep Sea Drilling Project (DSDP) Leg 28 completed sampling at four drill sites in the early 1970's but had low recovery and did not sample the Early Cenozoic. Other drilling has been restricted to the McMurdo Sound area of the western Ross Sea and results can be correlated into the Victoria Land Basin but not eastward across basement highs. Further, Early Cenozoic and Cretaceous rocks have not been sampled. A new opportunity is developing to drill from the Ross Ice Shelf. This is a successor program to the Cape Roberts Drilling Project. One overriding difficulty is the need for site surveys at drilling locations under the ice shelf. This project will overcome this impediment by conducting marine geophysical drill site surveys at the front of the Ross Ice Shelf in the Central Trough and Eastern Basin. The surveys will be conducted a kilometer or two north of the ice shelf front where recent calving events have resulted in a southerly position of the ice shelf edge. In several years the northward advance of the ice shelf will override the surveyed locations and drilling could be accomplished. Systems to be used include swath bathymetry, gravity, magnetics, chirp sonar, high resolution seismic profiling, and 48 fold seismics. Cores will be collected to obtain samples for geotechnical properties, to study sub-ice shelf modern sedimentary processes, and at locations where deeper section is exposed.<br/><br/>This survey will include long profiles and detailed grids over potential drill sites. Survey lines will be tied to existing geophysical profiles and DSDP 270. A recent event that makes this plan timely is the calving of giant iceberg B-15 (in March, 2000) and others from the ice front in the eastern Ross Sea. This new calving event and one in 1987 have exposed 16,000 square kilometers of seafloor that had been covered by ice shelf for decades and is not explored. Newly exposed territory can now be mapped by modern geophysical methods. This project will map geological structure and stratigraphy below unconformity RSU6 farther south and east, study the place of Roosevelt Island in the Ross Sea rifting history, and determine subsidence history during Late Cenozoic time (post RSU6) in the far south and east. Finally the project will observe present day sedimentary processes beneath the ice shelf in the newly exposed areas.
This award, provided jointly by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to transform three temporary seismometers in the Antarctic Peninsula into semi-permanent stations and to continue basic research using these data. During 1997 and 1998, a network of 11 broadband seismographs in the Antarctic Peninsula region and southernmost Chilean Patagonia were installed and maintained. Data return from this project has been excellent and interesting initial results have been produced. The continued operation of these instruments over a longer time period would be highly beneficial because the number of larger magnitude regional earthquakes is small and so a longer time is needed to acquire data. However, instruments from this project are borrowed from the IRIS-PASSCAL instrument pool and must be returned to PASSCAL in April, 1999. This award provides funds to convert three stations at permanent Chilean bases in the Antarctic to permanent stations, and to continue the seismological investigation of the region for a period of four years. As part of this project, a fourth station, in Chilean Patagonia, will continue to be operated using Washington University equipment. The funding of this project will enable continued collaboration between Washington University and the Universidad de Chile in the operation of these stations, and the data will be forwarded to the IRIS data center as well as to other international seismological collaborators. Mutual data exchanges with other national groups with Antarctic seismology research programs will provide access to broadband data from a variety of other proprietary broadband stations in the region. The data will be used to study the seismicity and upper mantle velocity structure of several complicated tectonic regions in the area, including the South Shetland subduction zone, the Bransfield backarc rift, and diffuse plate boundaries in Patagonia, Drake Passage, and along the South Scotia Ridge. In particular, the operation of these stations over a longer time period will allow a better understanding of the seismicity of the South Shetland Trench, an unusual subduction zone showing very slow subduction of young lithosphere. These seismometers will also be used to record airgun shots during a geophysical cruise in the Bransfield Strait that is being planned by the University of Texas for April, 2000. These data will provide important constraints on the crustal structure beneath the stations, and the improved structural models will enable implementation of more precise earthquake location procedures in support of a seismological understanding of the region.
Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea.
This project examines the role of glacier dynamics in glacial sediment yields. The results will shed light on how glacial erosion influences both orogenic processes and produces sediments that accumulate in basins, rich archives of climate variability. Our hypothesis is that erosion rates are a function of sliding speed, and should diminish sharply as the glacier's basal temperatures drop below the melting point. To test this hypothesis, we will determine sediment accumulation rates from seismic studies of fjord sediments for six tidewater glaciers that range from fast-moving temperate glaciers in Patagonia to slow-moving polar glaciers on the Antarctic Peninsula. Two key themes are addressed for each glacier system: 1) sediment yields and erosion rates by determining accumulation rates within the fjords using seismic profiles and core data, and 2) dynamic properties and basin characteristics of each glacier in order to seek an empirical relationship between glacial erosion rates and ice dynamics. The work is based in Patagonia and the Antarctic Peninsula, ideal natural laboratories for these purposes because the large latitudinal range provides a large range of precipitation and thermal regimes over relatively homogeneous lithologies and tectonic settings. Prior studies of these regions noted significant decreases in glaciomarine sediment accumulations in the fjords to the south. As well, the fjords constitute accessible and nearly perfect natural sediment traps.<br/><br/>The broader impacts of this study include inter-disciplinary collaboration with Chilean glaciologists and marine geologists, support for one postdoctoral and three doctoral students, inclusion of undergraduates in research, and outreach to under-represented groups in Earth sciences and K-12 educators. The results of the project will also contribute to a better understanding of the linkages between climate and evolution of all high mountain ranges.
This proposal is for the continuation and expansion of an underway program on the R/V Laurence M. Gould to measure dissolved carbon dioxide gas (pCO2) along with occasional total carbon dioxide (TCO2) in surface waters on transects of Drake Passage. The added observations include dissolved oxygen, as well as nutrient and carbon-13. The proposed work is similar to the underway measurement program made aboard R/V Nathaniel B. Palmer, and complements similar surface temperature and current data.<br/>The Southern Ocean is an important component of the global carbon budget. Low surface temperatures with consequently low vertical stability, ice formation, and high winds produce a very active environment for the exchange of gaseous carbon dioxide between the atmospheric and oceanic reservoirs. The Drake Passage is the narrowest point through which the Antarctic Circumpolar Current and its associated fronts must pass, and is the most efficient location for the measurement of latitudinal gradients of gas exchange. The generated time series will contribute towards two scientific goals: the quantification of the spatial and temporal variability and trends of surface carbon dioxide, oxygen, nutrients and C-13, and an understanding of the dominant processes that contribute to the observed variability.
The proposal is to develop an instrument that can simultaneously measure the sound speed and magnetic fields at three heights in the solar atmosphere. The instrument will use magneto-optical filters tuned to the solar absorption lines at 422 nm (Ca I), 589 nm (Na D2), and 770 nm (K) to make measurements of Doppler velocities and longitudinal magnetic field. These lines form in the mid- and low-chromosphere and photosphere, respectively. In addition, the instrument will also use a Fabry-Perot etalon as a narrowband filter to measure the intensity variations of the 1083 nm (He I) line that is formed high in the chromosphere and which shows the location of the "foot points" of coronal holes. Together, the four lines will allow studying wave motions throughout the solar atmosphere. The instrument will record images of the Sun every 10 seconds with a spatial resolution of 1 arc-second. Thus, the project will be fostering the development of existing magneto-optical filter technology to a new level. Upon construction, the telescope will be tested at South Pole for a long period of uninterrupted observations. Both the local and global helioseismic analysis procedures will be utilized to identify and to characterize different types of waves present in the solar atmosphere. These observations will allow determining the structure and dynamics of the Sun's atmosphere through seismic measurements and, thus, improve the atmosphere models, assess the role of waves in heating the chromosphere/corona and driving the solar wind, and better understand how the Sun's atmosphere couples to the interior. The broader impact of the proposed project is two fold. First, there is a potential benefit to the science and to the society because it is believed that the solar atmosphere is a "home" to many phenomena that can have a direct effect on the solar activity, including flares, coronal mass ejections, and the solar wind. Understanding the structure and dynamics of the solar atmosphere will therefore lead to a better understanding of the Sun-Earth connection. The collected data will be made available to other researchers at DVDs. The broader audience of general public will be reached through presentations at high schools, libraries, and community events, and news articles in the general press. Most of the research materials will also be placed in the Web.
This award supports development of a new modeling approach that will extract information about past snow accumulation rate in both space and time in the vicinity of the future ice core near the Ross-Amundsen divide of the West Antarctic Ice Sheet (WAIS). Internal layers, detected by ice-penetrating radar, are isochrones, or former ice-sheet surfaces that have been buried by subsequent snowfall, and distorted by ice flow. Extensive ice-penetrating radar data are available over the inland portion of the WAIS. Layers have been dated back to 17,000 years before present. The radar data add the spatial dimension to the temporally resolved accumulation record from ice cores. Accumulation rates are traditionally derived from the depths of young, shallow layers, corrected for strain using a local 1-D ice-flow model. Older, deeper layers have been more affected by flow over large horizontal distances. However, it is these deeper layers that contain information on longer-term climate patterns. This project will use geophysical inverse theory and a 2.5D flow-band ice-flow forward model comprising ice-surface and layer-evolution modules, to extract robust transient accumulation patterns by assimilating multiple deeper, more-deformed layers that have previously been intractable. Histories of divide migration, geothermal flux, and surface evolution will also be produced. The grant will support the PhD research of a female graduate student who is a mentor to female socio-economically disadvantaged high-school students interested in science, through the University of Washington Women's Center. It will also provide a research<br/>experience for an undergraduate student, and contribute to a freshman seminar on Scientific Research.
This award is for support for three years of funding to study the effects of impurities on the flow of poly- crystalline ice. It has been known for thirty years that both hydrofluoric acid (HF) and hydrochloric acid (HCl) dramatically decrease the strength of ice and recent work by the author's group has shown that sulfuric acid (H2SO4) produces a similar reduction in strength. However, these data are for single crystals at strain rates and stresses that far exceed those found in glaciers and ice sheets, and often at concentrations that far exceed those in natural ice. Therefore, it is not known how impurities found in nature affect the flow of polycrystalline ice at slow strain rates. In this research, the effects of nitric acid and sulfuric acid (which are naturally occurring impurities in ice) on the microstructure (dislocation structure, grain boundary structure and location of the acids) and creep of polycrystalline ice (at a range of temperatures and stresses) will be determined. The ice's response to creep deformation will be studied using a combination of x-ray topography, optical microscopy and scanning electron microscopy. X-ray microanalysis in an environmental scanning electron microscope will be used to study the location of impurities. The structure and creep behavior of the acid-doped ice will be compared with those of both high-purity laboratory-grown ice and ice from Byrd Station, Antarctica. The end-result of this project will be to elucidate the effects of naturally-occurring acid impurities on the mechanical properties of polycrystalline ice under conditions relevant to the deformation of glaciers and ice sheets, including and understanding of how impurities affect the underlying deformation mechanisms.
This award supports a project to obtain stable isotope profiles from shallow (<100 m) ice cores from East Antarctica, to add to the growing database of environmental proxy data collected under the auspices of the "ITASE" (International TransAntarctic Scientific Expedition) program. In Antarctica, the instrumental record of climate is particularly short (~40 years except in a few isolated locations on the coast), and ice core proxy data are the only means available for extending this record into the past. The use of stable isotopes of water (18-O/16-O and D/H ratios) from ice cores as proxies for temperature is well established for both very short (i.e. seasonal) and long timescales (centuries, millennia). Using multivariate regression methods and shallow ice cores from West Antarctica, a reconstruction of Antarctic climate over the last ~150 years has been developed which suggests the continent has been warming, on average, at a rate of ~0.2 K/century. Further improving these reconstructions is the chief motivation for further extending the US ITASE project. Ten to fifteen shallow (~ 100 m) from Victoria Land, East Antarctica will be obtained and analyzed. The core will be collected along a traverse route beginning at Taylor Dome and ending at the South Pole. Age-depth relationships for the cores will be determined through a combination of stable isotopes, visual stratigraphy and seasonal chemical signatures and marker horizons. Reconstructions of Antarctic climate obtained from these cores will be incorporated into the global network of paleoclimate information, which has been important in science, policy and educational contexts. The project will include graduate student and postdoctoral training and field experience.
This award supports a project to improve understanding of atmospheric photochemistry over West Antarctica, as recorded in snow, firn and ice. Atmospheric and firn sampling will be undertaken as part of the U.S. International Trans-Antarctic Scientific Expedition (US ITASE) traverses. Measurements of hydrogen peroxide (H2O2) and formaldehyde (HCHO) will be made on these samples and a recently developed, physically based atmosphere-to-snow transfer model will be used to relate photochemical model estimates of these components to the concentrations of these parameters in the atmosphere and snow. The efficiency of atmosphere-to-snow transfer and the preservation of these components is strongly related to the rate and timing of snow accumulation. This information will be obtained by analyzing the concentration of seasonally dependent species such as hydrogen peroxide, nitric acid and stable isotopes of oxygen. Collection of samples along the US ITASE traverses will allow sampling at a wide variety of locations, reflecting both a number of different depositional environments and covering much of the West Antarctic region.
This project is an international collaborative investigation of geographic structuring, founding of new colonies, and population change of Adelie penguins (Pygoscelis adelia) nesting on Ross and Beaufort islands, Antarctica. The long-term changes occurring at these colonies are representative of changes throughout the Ross Sea, where 30% of all Adelie penguins reside, and are in some way related to changing climate. The recent grounding of two very large icebergs against Ross and Beaufort islands, with associated increased variability in sea-ice extent, has provided an unparalleled natural experiment affecting wild, interannual swings in colony productivity, foraging effort, philopatry and recruitment. Results of this natural experiment can provide insights into the demography and geographic population structuring of this species, having relevance Antarctic-wide in understanding its future responses to climate change as well as interpreting its amazingly well known Holocene history. This ongoing study will continue to consider the relative importance of resources that constrain or enhance colony growth (nesting habitat, access to food); the aspects of natural history that are affected by exploitative or interference competition among neighboring colonies (breeding success, foraging effort); climatic factors that influence the latter, especially sea ice patterns; and behavioral mechanisms that influence colony growth as a function of initial size and location (emigration, immigration). An increased effort will focus on understanding factors that affect over-winter survival. The hypothesis is that the age structure of Cape Crozier has changed over the past thirty years and no longer reflects the smaller colonies nearby. Based on recent analyses, it appears that the Ross Island penguins winter in a narrow band of sea ice north of the Antarctic Circle (where daylight persists) and south of the southern boundary of the Antarctic Circumpolar Current (where food abounds). More extensive winter ice takes the penguins north of that boundary where they incur higher mortality. Thus, where a penguin winters may be due to the timing of its post-breeding departure (which differs among colonies), which affects where it first encounters sea ice on which to molt and where it will be transported by the growing ice field. Foraging effort and interference competition for food suggested as factors driving the geographic structuring of colonies. The research includes a census of known-age penguins, studies of foraging effort and overlap among colonies; and identification of the location of molting and wintering areas. Information will be related to sea-ice conditions as quantified by satellite images. Demographic and foraging-effort models will be used to synthesize results. The iceberg natural experiment is an unparalleled opportunity to investigate the demographics of a polar seabird and its response to climate change. The marked, interannual variability in apparent philopatry, with concrete data being collected on its causes, is a condition rarely encountered among studies of vertebrates. Broader impacts include collaborating with New Zealand and Italian researchers, involving high school teachers and students in the fieldwork and continuing a website to highlight results to both scientists and the general public.
Phaeocystis Antarctica is a widely distributed phytoplankton that forms dense blooms and aggregates in the Southern Ocean. This phytoplankton and plays important roles in polar ecology and biogeochemistry, in part because it is a dominant primary producer, a main component of organic matter vertical fluxes, and the principal producer of volatile organic sulfur in the region. Yet P. Antarctica is also one of the lesser known species in terms of its physiology, life history and trophic relationships with other organisms; furthermore, information collected on other Phaeocystis species and from different locations may not be applicable to P. Antarctica in the Ross Sea. P. Antarctica occurs mainly as two morphotypes: solitary cells and mucilaginous colonies, which differ significantly in size, architecture and chemical composition. Relative dominance between solitary cells and colonies determines not only the size spectrum of the population, but also its carbon dynamics, nutrient uptake and utilization. Conventional thinking of the planktonic trophic processes is also challenged by the fact that colony formation could effectively alter the predator-prey interactions and interspecific competition. However, the factors that regulate the differences between solitary and colonial forms of P. Antarctica are not well-understood. The research objective of this proposal is therefore to address these over-arching questions:<br/>o Do P. Antarctica solitary cells and colonies differ in growth, composition and<br/>photosynthetic rates?<br/>o How do nutrients and grazers affect colony development and size distribution of P. <br/>Antarctica?<br/>o How do nutrients and grazers act synergistically to affect the long-term population<br/>dynamics of P. Antarctica? Experiments will be conducted in the McMurdo station with natural P. Antarctica assemblages and co-occurring grazers. Laboratory experiments will be conducted to study size-specific growth and photosynthetic rates of P. Antarctica, size-specific grazing mortality due to microzooplankton and mesozooplankton, the effects of macronutrients on the (nitrogen compounds) relative dominance of solitary cells and colonies, and the effects of micronutrient (Fe) and grazing related chemical signals on P. Antarctica colony development. Because this species is of critical importance in the Southern Ocean, and because this research will provide critical information on factors that regulate the role of P.Antarctica in food webs and biogeochemical cycles, a major gap in knowledge will be addressed. This project will train two marine science PhD students. The investigators will also collaborate with the School of Education and a marine science museum to communicate polar science to a broader audience.
This proposal is to continue operation and scientific studies with the middle-frequency (MF, 1-30 MHz) mesospheric radar deployed at the British Antarctic station Rothera in 1996. This system is now a key site in the Antarctic MF radar chain near 68 deg. S, which includes also MF radars at Syowa (Japan) and Davis (Australia) stations. This radar comprises the winds component of a developing instrument suite for the mesosphere-thermosphere (MLT) studies at Rothera - a focus of the new BAS 5-year plan, which also includes the Fe temperature lidar (formerly at South Pole) and the mesopause airglow imager for gravity wave studies (formerly at Halley). The Rothera MF radar has just had its antennas and electronics upgraded to achieve better signal-to-noise ratio and more continuous measurements in height and time. The main focus of the proposed research is to extend the knowledge of the polar mesosphere dynamics. The instrument suite at Rothera is ideally positioned for correlative interhemispheric studies with northern hemisphere sites at Poker Flat, Alaska (65 deg. N) and ALOMAR, Norway (69 deg. N) having comparable instrumentation. Further research efforts performed with continued funding will focus on: (1) multi-instrument collaborative studies at Rothera to quantify as fully as possible the dynamics, structure, and variability of the MLT at that location, (2) multi-site (and multi-instrument) studies of large-scale dynamics and variability in the Antarctic (together with the radars and other instrumentation at Davis and Syowa), and (3) interhemispheric studies employing instruments (e.g., the Na resonance lidar and MF radar) at Poker Flat and ALOMAR. It is expected that these studies will lead to a more detailed understanding of (1) mean, tidal, and planetary wave structures at polar latitudes, (2) seasonal, inter-annual, and short-term variability of these structures, (3) hemispheric differences in the tidal and planetary wave structures arising from different source and wave interaction conditions, and (4) the relative influences of gravity waves in the two hemispheres. Such studies will also contribute more generally to an increased awareness of the role of high-latitude processes in global atmospheric dynamics and variability.
This award supports a project to measure the elemental and isotopic composition of firn air and occluded air in shallow boreholes and ice cores from the WAIS Divide site, the location of a deep ice-coring program planned for 2006-07 and subsequent seasons. The three primary objectives are: 1) to establish the nature of firn air movement and trapping at the site to aid interpretations of gas data from the deep core; 2) to expand the suite of atmospheric trace gas species that can be measured in ice and replicate existing records of other species; and 3) to inter-calibrate all collaborating labs to insure that compositional and isotopic data sets are inter-comparable. The program will be initiated with a shallow drilling program during the 05/06 field season which will recover two 300+m cores and firn air samples. The ice core and firn air will provide more than 700 years of atmospheric history that will be used to address a number of important questions related to atmospheric change over this time period. The research team consists of six US laboratories that also plan to participate in the deep core program. This collaborative research program has a number of advantages. First, the scientists will be able to coordinate sample allocation a priori to maximize the resolution and overlap of records of interrelated species. Second, sample registration will be exact, allowing direct comparison of all records. Third, a coherent data set will be produced at the same time and all PI.s will participate in interpreting and publishing the results. This will insure that the best possible understanding of gas records at the WAIS Divide site will be achieved, and that all work necessary to interpret the deep core is conducted in a timely fashion. The collaborative structure created by the proposal will encourage sharing of techniques, equipment, and ideas between the laboratories. The research will identify impacts of various industrial/agricultural activities and help to distinguish them from natural variations, and will include species for which there are no long records of anthropogenic impact. The work will also help to predict future atmospheric loadings. The project will contribute to training scientists at several levels, including seven undergraduates, two graduate students and one post doctoral fellow.
This award supports the study of the drift and break-up of Earth's largest icebergs, which were recently released into the Ross Sea of Antarctica as a result of calving from the Ross Ice Shelf. The scientific goals of the study are to determine the physics of iceberg motion within the dynamic context of ocean currents, winds, and sea ice, which determine the forces that drive iceberg motion, and the relationship between the iceberg and geographically and topographically determined pinning points on which the iceberg can ground. In addition, the processes by which icebergs influence the local environments (e.g., sea ice conditions near Antarctica, access to penguin rookeries, air-sea heat exchange and upwelling at iceberg margins, nutrient fluxes) will be studied. The processes by which icebergs generate globally far-reaching ocean acoustic signals that are detected within the global seismic (earthquake) sensing networks will also be studied. A featured element of the scientific research activity will be a field effort to deploy automatic weather stations, seismometer arrays and GPS-tracking stations on several of the largest icebergs presently adrift, or about to be adrift, in the Ross Sea. Data generated and relayed via satellite to home institutions in the Midwest will motivate theoretical analysis and computer simulation; and will be archived on an "iceberg" website (http://amrc.ssec.wisc.edu/amrc/iceberg.html) for access by scientists and the general public. At the most broad level, the study is justified by the fact that icebergs released by the Antarctic ice sheet represent the largest movements of fresh water within the natural environment (e.g., several of the icebergs to be studied, B15, C19 and others calved since 2000 CE, represent over 6000 cubic kilometers of fresh water-an amount roughly equivalent to 100 years of the flow of the Nile River). A better understanding of the impact of iceberg drift through the environment, and particularly the impact on ocean stratification and mixing, is essential to the understanding of the abrupt global climate changes witnessed by proxy during the ice age and of concern under conditions of future greenhouse warming. On a more specific level, the study will generate a knowledge base useful for the better management of Antarctic logistical resources (e.g., the shipping lanes to McMurdo Station) that can occasionally be influenced by adverse effects icebergs have on sea ice conditions.
Aquatic-terrestrial transition zones are crucial environments in understanding the biogeochemistry of landscapes. In temperate watersheds, these areas are generally dominated by riparian zones, which have been identified as regions of special interest for biogeochemistry because of the increased microbial activity in these locations, and because of the importance of these hydrological margins in facilitating and buffering hydrologic and biogeochemical exchanges between terrestrial and aquatic ecosystems. In the Antarctic Dry Valleys, terrestrial-aquatic transition zones are intriguing landscape features because of the vast importance of water in this polar desert, and because the material and energy budgets of dry valley ecosystems are linked by hydrology. Hydrological margins in aquatic-terrestrial transition zones will be studied in the Dry Valleys of Antarctica to answer two overarching questions: (1) what are the major controls over hydrologic and biogeochemical exchange across aquaticterrestrial transition zones and (2) to what extent do trends in nutrient cycling (e.g. nitrogen cycling) across these transition zones reflect differences in microbial communities or function vs. differences in the physical and chemical environment (e.g., redox potential)? The hydrologic gradients that define these interfaces provide the opportunity to assess the relative influence of physical conditions and microbial biodiversity and functioning upon biogeochemical cycling. Coordinated hydrologic, biogeochemical, and molecular microbial studies will be executed within hydrologic margins with the following research objectives: to determine the role of sediment characteristics, permafrost and active layer dynamics, and topography on sub-surface water content and distribution in hydrologic margins, to determine the extent to which transformations of nitrogen in hydrological margins are influenced by physical conditions (i.e., moisture, redox potential and pH) or by the presence of specific microbial communities (e.g., denitrifiers), and to characterize the microbial community structure and function of saturated zones.<br/><br/>This proposed research will provide an improved understanding of the interaction of liquid water, soils, microbial communities, and biogeochemistry within the important hydrologic margin landscape units of the dry valleys. Dry valleys streams and lakes are unique because there is no influence of higher vegetation on the movement of water and may therefore provide a model system for understanding physical and hydrological influences on microbial ecology and biogeochemistry. Hence the findings will contribute to Antarctic science as well as the broader study of riparian zones and hydrologic margins worldwide. Graduate students and undergraduate students will be involved with fieldwork and research projects. Information will be disseminated through a project web site, and outreach activities will include science education in local elementary, middle and high schools near the three universities involved.
The large subglacial Lake Vostok in Antarctica is unique ecological site with a novel microbial biota. The temperatures, pressures and lack of light all select for organisms that may not exist anywhere else on Earth. The accretion ice (lake water frozen to the bottom of the lower surface of the glacier) has preserved microbial samples from each region of Lake Vostok as the glacier passes over and into the lake. Thus, without contaminating the lake with microorganisms from the surface, microbes originating from the lake can be collected, transported to the laboratory and studied. Two of the deepest ice cores sections in this project are part of the international allocation. The will be shared between four researchers (Sergey Bulat from Russia, Jean-Robert Petit and Daniel Prieur from France, Scott Rogers from USA). The United States team will study, isolate, and characterize bacteria, fungi, and viruses that have been sampled from the lake through the process of ice accretion to the lower surface of 3500+m thick glacier overriding the lake. The project will involve a suite of methods, including molecular, morphological, and cultural. This includes observation and description by fluorescence, light, and electron microscopy, isolation on thirteen separate cultural media, polymerase chain reaction amplification, DNA sequencing, and phylogenetic analyses. Eleven accretion ice core sections, as well as two glacial ice core sections. As well as two glacial ice core sections will be studied. The accretion ice core sections, as well as two glacial ice core sections will be studied. The accretion ice core sections represent all of the major regions of the lake that have been sampled by the accretion process in the vicinity of the Vostok 5G ice core. The broader impacts of the work relate to the impact the results will have on the filed. These long=isolated lakes, deep below the Antarctic ice sheet may contain novel uniquely adapted organisms. Glacial ice contains an enormous diversity of entrapped microbes, some of which may be metabolically active in the ice. The microbes from Lake Vostok are of special interest, since they are adapted to cold, dark, and high pressure. Thus, their enzyme systems and biochemical pathways may be significantly different from those in the microbes that are the subject of current studies. As such, these organisms may form compounds that may have useful applications. Also, study of the accretion ice, and eventually the water, from Lake Vostok will provide a basis for the study of other subglacial lakes. Additionally, study of the microbes in the accretion ice will be useful to those planning to study analogous systems on ice-covered planets and moons.
Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea.
This award supports a project to use three downhole instruments - an optical logger; a<br/>miniaturized biospectral logger at 420 nm (miniBSL-420); and an Acoustic TeleViewer (ATV) - to log a 350-m borehole at the WAIS Divide drill site. In addition, miniBSL-224 (at 224 nm) and miniBSL-420 will scan ice core sections at NICL to look for abrupt climate changes, volcanic ash, microbial concentrations, and correlations among them. Using the optical logger and ATV to log bubble number densities vs depth in a WAIS Divide borehole, we will detect annual layers, from which we can establish the age vs depth relation to the bottom of the borehole that will be available during the three-year grant period. With the same instruments we will search for long-period modulation of bubble and dust concentrations in order to provide definitive evidence for or against an effect of long-period variability of the sun or solar wind on climate. We will detect and accurately date ash layers in a WAIS Divide borehole. We will match them with ash layers that we previously detected in the Siple Dome borehole, and also match them with sulfate and ash layers found by others at Vostok, Dome Fuji, Dome C, and GISP2. The expected new data will allow us to extend our recent study which showed that the Antarctic record of volcanism correlates with abrupt climate change at a 95% to >99.8% significance level and that the volcanic signatures at bipolar locations match at better than 3 sigma during the interval 2 to 45 kiloyears. The results to be obtained during this grant period will position us to extend an accurate age vs depth relation and volcano-climate correlations to earlier than 150 kiloyears ago in the future WAIS Divide borehole to be drilled to bedrock. Using the miniBSLs to identify biomolecules via their fluorescence, we will log a 350-m borehole at WAIS Divide, and we will scan selected lengths of ice core at NICL. Among the biomolecules the miniBSLs can identify will be chlorophyll, which will provide the first map of aerobic microbes in ice, and F420, which will provide the first map of methanogens in ice. We will collaborate with others in relating results from WAIS Divide and NICL ice cores to broader topics in climatology, volcanology, and microbial ecology. We will continue to give broad training to undergraduate and graduate students, to attract underrepresented minorities to science, engineering, and math, and to educate the press and college teachers. A deeper understanding of the causes of abrupt climate change, including a causal relationship with strong volcanic eruptions, can enable us to understand and mitigate adverse effects on climate.
The proposed work would modify an existing 4-channel all-sky camera at South Pole in order to observe several types of auroras, and to distinguish the cusp reconnection aurora from the normal plasma sheet precipitation. The camera will simultaneously operate in four wavelength regions that allow a distinction between auroras that are created by higher energy electrons (> 1 keV) and those created by low energy (<500 eV) precipitation. The cusp is the location where plasma enters the magnetosphere through the process of magnetic reconnection. This reconnection occurs where the Interplanetary Magnetic Field (IMF) and the terrestrial magnetic field are oriented in opposite directions. Using the IMAGE (Imager for Magnetopause to Aurora Global Exploration) satellite ultraviolet optical data it has been shown that cusp precipitation can be seen in different regions, which depend on the orientation of the IMF. South Pole station is uniquely located for optical observations of the aurora because of the 24 hours of darkness during austral winter and the appearance of the auroral oval within the field of view of all-sky cameras.
9980452 Harvey This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for continuation of the Antarctic Search for Meteorites (ANSMET). Since 1976, ANSMET has recovered more than 10,000 meteorite specimens from locations along the Transantarctic Mountains. This award supports continued recovery of Antarctic meteorites during six successive austral summer field seasons, starting with the 2000-2001 season and ending with the 2005-2006 season. Under this project, systematic searches for meteorite specimens will take place at previously discovered stranding surfaces, and reconnaissance work will be conducted to discover and explore the extent of new areas with meteorite concentrations. ANSMET recovery teams will deploy by air to locations in the deep field for periods of 5-7 weeks. While at the meteorite stranding surface, field team members will search the ice visually, traversing on foot or on snowmobile. Specimens will be collected under the most sterile conditions practical and samples will remain frozen until returned to the Johnson Space Center (JSC) in Houston, Texas. At the JSC, initial characterization and sample distribution to all interested researchers takes place under the auspices of an interagency agreement between NSF, NASA, and the Smithsonian Institution. The impact of ANSMET has been substantial and this will continue under this award. The meteorites recovered by ANSMET are the best and most reliable source of new, non-microscopic extraterrestrial material, providing essential "ground-truth" concerning the materials that make up the asteroids, planets and other bodies of our solar system. The system for their characterization and distribution is unparalleled and their subsequent study has fundamentally changed our understanding of the solar system. ANSMET meteorites have helped researchers explore the conditions that were present in the nebula from which our solar system was born 4.556 billion years ago and provided samples of asteroids, ranging from primitive bodies unchanged since the formation of the solar system to complex, geologically active miniature planets. ANSMET samples proved, against the conventional wisdom, that some meteorites actually represent planetary materials, delivered to us from the Moon and Mars, completely changing our view of the geology of those bodies. ANSMET meteorites have even generated a new kind of inquiry into one of the most fundamental scientific questions possible; the question of biological activity in the universe as a whole. Over the past twenty years, ANSMET meteorites have economically provided a continuous and readily available supply of extraterrestrial materials for research, and should continue to do so in the future.
9909436 Farley This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an investigation of the uplift history of the Dry Valleys segment of the Transantarctic Mountains. The overall goal is to further constrain the exhumation history of the Transantarctic Mountains by using the newly developed apatite (U-Th)/He dating method on samples collected in vertical profiles. This approach, combined with existing apatite fission track information will constrain the rate and patterns of exhumation across the Transantarctic Mountains since their inception as a rift-flank uplift in the early Cenozoic. This project will complement other projects and build on previous interpretations of the exhumation and tectonic history determined using apatite fission track thermochronology. It will bridge the gap between information on erosion rates determined from fission track thermochronology and from cosmogenic surface exposure dating and integrate the exhumation history of the mountains with their landscape evolution. As such, the results from this project will address an outstanding problem in Antarctic science; namely the stability of the East Antarctic Ice Sheet, and the timing of the transition from a "warm" dynamic ice sheet to a cold polar ice sheet. Highly relevant to this issue is the landscape evolution of the Transantarctic Mountains because many diverse lines of evidence for the rate of landscape evolution have been used to argue for a dynamic ice sheet up until either the Pliocene (the "dynamic" ice sheet model) or the middle Miocene (the "stable" ice sheet model). Understanding the past stability or dynamic fluctuations of the East Antarctic ice sheet with respect to the climate record is, of course, important for understanding how the present ice sheet may respond to global warming. The specific objective of this project is to determine apatite (U-Th)/He age versus elevation trends for a number of vertical profiles from locations within the Transantarctic Mountain front and across the structural grain of the range. Fission track data already exist for all of these profiles, with apatite fission track ages ranging from 150-30 Ma. The greater precision of the (U-Th)/He technique and the fact it records information at lower temperatures (closure temperature of ~70 degrees Celsius; limits of 40-85 degrees Celsius for the He partial retention zone) will allow examination of the exhumation history of the TAM in more detail from ca 130 Ma to ~20 Ma. Another facet is to examine areas where Cretaceous exhumation is recorded and areas where the fission track profiles indicate periods of thermal and tectonic stability and minimal erosion throughout the Cretaceous. The variation of timing of the onset of more rapid exhumation accompanying uplift and formation of the Transantarctic Mountains in the early Cenozoic will also be examined.
This award supports a project to develop computational models to simulate ice-shelf rift propagation using a combination of well-established ice-shelf creep-flow models and new crevasse models, based on linear elastic fracture mechanics (LEFM). The overall objective of the proposed work is to simulate rift propagation and eventual large iceberg calving,and place those processes within a larger ice sheet and climate context. The work will proceed in stages, first developing models of single-and multiple-crevasse propagation; then using those models to evaluate propagation sensitivity to various environmental conditions; and third developing models that incorporate both crevasse propagation and advection within an ice- shelf system. Model development will be guided by and evaluated according to satellite observations of rift propagation in several characteristic locations on Antarctic ice shelves. New numerical models of fracture in ice will have applications to many problems in glaciology. The research proposed here is directed toward large rift formation in ice shelves and subsequent iceberg calving. It is motivated by the need to understand observed changes in modern ice shelves,and their connection to climate. Where it has been sampled, the sedimentary record of the Weddell Sea sector implies Peninsular ice shelf variability on millennial time scales. The ability to simulate iceberg calving in a credible way will improve our ability to reproduce such events and place the complete cycle of ice shelf advance and retreat in an ice-dynamics context. That will, in turn, enable us to place ice-shelf cycles within the climate cycles that ultimately drive ice-sheet mass balance.
This award supports the development of novel methods for digital image analysis of glacial ice cores that are stored at the National Ice Core Laboratory (NICL) in Denver, Colorado. Ice cores are a critical source of information on how Earth has changed over time, since indicators of local climate (snow accumulation, temperature), regional characteristics (wind-blown materials such as sea salt, dust and pollen), global processes (e.g., CO2, methane), and even extraterrestrial influences (cosmogenic isotopes) are stored in the ice on a common time scale. This project will develop a high-resolution optical scanning system for laboratory curation of ice core images, internet-based search and retrieval capabilities, a digital image analysis system specifically for ice core studies, and methods to integrate ice core image analysis with other dating methods. These tools will be developed and tested in conjunction with scientific investigations of NICL holdings. Optical scanning and analysis tools will improve understanding of the historical development of the ice collected from a particular location and will help to resolve challenges such as ice that has lost stratigraphic order through flow processes. <br/>By providing permanent online digital archives of ice core images, this project will greatly improve the documentation and availability of ice core data while reducing time and costs for subsequent scientific investigations. Using the internet, ice core scientists will be able to determine the appropriateness of specific NICL holdings for various scientific studies. By optically scanning ice cores as they are processed at NICL, any researcher will be able to examine an ice core in similar detail to the few investigators who were fortunate enough to observe it before modifications from sampling and storage. Re-examination of cores could be done decades later by anyone at any location, which is not possible now because only the interpretation of the original observer is recorded. Integration of digital image data into ice core analysis will speed discovery, allow collaborative interpretation, and enhance consistency of analysis to improve ice core dating, identification of melt layers, location of flow disturbances, and more. The equipment will be housed at NICL and will be available to the broad community, improving scientific infrastructure.<br/>This work will also have numerous broader impacts. Ice core science addresses fundamental questions of human interest related to global warming, abrupt climate change, biogeochemical cycling, and more. The principal investigators broadly disseminate their scientific findings through numerous outlets, ranging from meeting with government officials, chairing and serving on NRC panels, writing popular books and articles, publishing in scientific literature, teaching classes, talking to civic groups, and appearing on radio and television. The results from ice core analyses have directly informed policymakers and will continue to do so. Thus, by improving ice core science, this projectl will benefit society.
0125610<br/>Waddington<br/><br/>This award provides three years of funding to study the transition from slow inland flow to fast ice stream flow by making use of a suite of geophysical measurements that have been made near the onset region of ice stream D in West Antarctica. These data provide a unique opportunity to develop and validate glaciological models of the controlling processes in ice stream onset zones. Important processes to quantify are motion at the bed and deformation in the ice. Previous analyses indicate that the controlling resistive forces shift from the bed to the sides during the transition from slow inland flow to fast, streaming flow. Model sensitivity analyses will be used to investigate the relative importance of feedbacks between basal processes and ice deformation in the transition from inland to ice stream flow. Model experiments will determine what factors control the location of the onset of streaming flow, and how that location might migrate when conditions at the bed, or along the flow direction, changes over time. The overall goal of this work is to improve understanding of the evolution of the WAIS drainage system. This study is a first step towards understanding the physics that govern the transition from slow inland flow to fast streaming flow.
This award supports a science management office for a pilot ice-core drilling and analysis program to test the feasibility of obtaining well-dated, high-resolution isotope and chemistry records from East Antarctica. Shallow ice cores will be obtained from two locations: 1) ~100 km from South Pole towards the Pole of Inaccessibility, as an extension of the Byrd Station-to-South Pole ITASE traverse [International Trans Antarctic Scientific Expedition]; 2) at Taylor Dome, near the original deep coring site, and (3) possibly at AGO 3 and AGO 4 as part of a logistics traverse to these sites. All of the cores collected will be sampled at very high resolution (~1/2 cm) and analyzed for major ions. Results from this calibration work, along with those from another project that is analyzing stable isotopes will be used to help plan a program of larger scope, with the objective of mapping the spatial expression of climate variability in East Antarctica. Funds are also provided to organize a community workshop for coordination of the second phase of US ITASE and for one workshop per year for two years dedicated to writing and preparation of scientific papers from phase one of US ITASE. In addition, route selection activities for the follow-on traverse activities in East Antarctica will be conducted using satellite image mapping. A summary document will be produced and made available to the community to help with planning of related field programs (e.g. deep ice radar, firn radar profiling, atmospheric chemistry, ice coring, snow surface properties for satellite observations, ice surface elevation and mass balance).
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to apply numerical modeling to constrain the uplift and exhumation history of the Transantarctic Mountains. The Transantarctic Mountains (TAM) are an anomalously high (>4500 m) and relatively broad (up to 200 km) rift-flank uplift demarcating the boundary between East and West Antarctica. Dynamics of the East Antarctic ice-sheet and the climate are affected by the mountain range, and an understanding of the uplift history of the mountain range is critical to understanding these processes. This project will constrain the uplift and denudation history of the Transantarctic Mountains based on thermo-mechanical modeling held faithful to thermochronological, geological, and geophysical data. The research will be the primary responsibility of post-doctoral researcher Audrey Huerta, working in collaboration with Dennis Harry, 1 undergraduate student, and 1 graduate student.<br/><br/>Thermochronologic evidence of episodic Cretaceous through Cenozoic rapid cooling within the TAM indicates distinct periods of uplift and exhumation. However, a more detailed interpretation of the uplift history is difficult without an understanding of the evolving thermal structure and topography of the TAM prior to and during uplift. These aspects of the mountain range can best be constrained by an understanding of the evolving regional tectonic setting. Proximity of the TAM to the West Antarctic Rift System (WARS) suggests a link between uplift of the TAM and extension within the WARS.<br/><br/>The project will integrate two techniques: lithospheric-scale geodynamic modeling and crustal-scale thermal modeling. The lithospheric-scale deformational and thermal evolution of TAM will be modeled by a finite element model designed to track the thermal and deformational response of the Antarctic lithosphere to a protracted extensional environment. Previous investigators have linked the high elevation and broad width of the TAM to a deep level of necking in which mantle thinning is offset from the location of crustal extension. In this study, a three-dimensional dynamic model will be used to track the uplift and thermal evolution of the TAM in a setting in which necking is at a deep level, and in which extension within the crust and extension within the mantle are offset. Velocity boundary conditions applied to the edges of the model will vary through time to simulate the extensional and transtensional evolution of the WARS. Because the model is dynamic, the thermal structure, strength, and strain field, evolve naturally in response to these initial and boundary conditions.<br/><br/>Dynamic models are uniquely suited to understanding lithospheric deformational and thermal evolution, however kinematic models are best suited for addressing the detailed thermal and exhumation history of crustal uplifts. Thus, a 2-dimensional kinematic-thermal model will be designed to simulate the uplift history of the TAM and the resulting erosional, topographic, and thermal evolution. Uplift will be modeled as normal-fault movement on a set of discrete fault planes with uplift rate varying through time. Erosion will be modeled as a diffusive process in which erosion rates can be varied through time (simulating climate changes), and vary spatially as a linear function of gradient and distance from the drainage divide. Synthetic time-temperature (t-T) histories will be calculated to compare model results to thermochronologic data.
9814816 Blankenship This award supports a four year project to develop of better understanding the ice streams of the Ross Sea Embayment (A--F) which drain the interior West Antarctic Ice Sheet (WAIS) by rapidly moving vast quantities of ice to the calving front of the Ross Ice Shelf. The project will examine the role of these ice streams as buffers between the interior ice and the floating ice shelves. The reasons for their fast flow, the factors controlling their current grounding-line-, margin-, and head-positions are crucial to any attempt at modeling the WAIS system and predicting the future of the ice sheet. For the Antarctic ice streams of the Siple Coast, the transition from no-sliding (or all internal deformation) to motion dominated by sliding is defined as the "onset-region". To fully understand (and adequately model) the WAIS, this onset region must be better understood. The lateral margins of the ice streams are also a transition that need better explanation. Hypotheses on controls of the location of the onset region range from the "purely-glaciologic" to the "purely-geologic. Thus, to model the ice sheet accurately, the basal boundary conditions (roughness, wetness, till properties) and a good subglacial geologic map, showing the distribution, thickness, and properties of the sedimentary basins, are required. These parameters can be estimated from seismic, radar, and other geophysical methods. The transition region of ice stream D will be studied in detail with this coupled geophysical experiment. In addition, selected other locations on ice streams C & D will be made, to compare and contrast conditions with the main site on ice stream D. Site-selection for the main camp will be based on existing radar, GPS, and satellite data as well as input from the modeling community.
Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an interdisciplinary study of fluvial sediments in Antarctica for evidence of what caused the greatest of all mass extinctions in the history of life at the Permian-Triassic boundary. This boundary was, until recently, difficult to locate and thought to be unequivocally disconformable in Antarctica. New studies, particularly of carbon isotopic chemostratigraphy and of paleosols and root traces as paleoecosystem indicators, together with improved fossil plant, reptile and pollen biostratigraphy, now suggest that the precise location of the boundary might be identified and have led to local discovery of iridium anomalies, shocked quartz, and fullerenes with extraterrestrial noble gases. These anomalies are associated with a distinctive claystone breccia bed, similar to strata known in South Africa and Australia, and taken as evidence of deforestation. There is already much evidence from Antarctica and elsewhere that the mass extinction on land was abrupt and synchronous with extinction in the ocean. The problem now is what led to such death and destruction. Carbon isotopic values are so low in these and other Permian-Triassic boundary sections that there was likely to have been some role for catastrophic destabilization of methane clathrates. Getting the modeled amount of methane out of likely reservoirs would require such catastrophic events as bolide impact, flood-basalt eruption or continental-shelf collapse, which have all independently been implicated in the mass extinction and for which there is independent evidence. Teasing apart these various hypotheses requires careful re-examination of beds that appear to represent the Permian-Triassic boundary, and search for more informative sequences, as was the case for the Cretaceous-Tertiary boundary. This collaborative research on geochemistry and petrography of boundary beds and paleosols (by Retallack), on carbon isotopic variation through the boundary interval (by Jahren), and on fullerenes, iridium and helium (by Becker) is designed to test these ideas about the Permian-Triassic boundary in Antarctica and to shed light on processes which contributed to this largest of mass extinctions on Earth. Fieldwork for this research will be conducted in the central Transantarctic Mountains and in Southern Victoria Land with an initial objective of examining the stratigraphic sequences for continuity across the boundary. Stratigraphic continuity is a critical element that must exist for the work to be successful. If fieldwork indicates sufficiently continuous sections, the full analytical program will follow fieldwork.
A 'horizontal ice core' was collected at the Mount Moulton blue ice field in West Antarctica and preliminary analyses of the sample material suggests that a ~500 kyr climate record is preserved in the ice at this site. This award will contribute to the understanding of the Mt Moulton record by assessing the potential for ice-flow induced deformation of the stratigraphic profile. In addition, this award builds on the recognition of blue ice areas as archives of long climate records by conducting reconnaissance studies for a potential horizontal ice core location at the Allan Hills in East Antarctica. The objectives of this project are to contribute to the glaciological understanding of blue ice areas in Antarctica. Ice flow conditions at the Mt Moulton blue ice field will be studied to assess the possibility that the stratigraphic record has been deformed and reconnaissance of a potential horizontal ice core site in the Allan Hills blue ice field will also be accomplished. Short field programs will be undertaken at each location to collect relevant measurements of ice flow and subglacial topography, and to conduct sampling of material that will enable the preservation of the stratigraphic sequences to be assessed.
This award supports a program of radar studies of internal stratigraphy and bedrock topography along the traverses for the U.S. component of the International Trans-Antarctic Scientific Expedition (US ITASE). The radar will provide information immediately available in the field on ice thickness and internal layer structure to help in the selection of core sites as the traverse proceeds. These data will also be useful in siting deeper millennial scale cores planned at less frequent intervals along the traverse, and in the selection of the location for the deep inland core planned for the future. In addition to continuous coverage along the traverse route, more detailed studies on a grid surrounding each of the core locations will be made to better characterize accumulation and bedrock topography in each area. This proposal is complimentary to the one submitted by the Cold Regions Research and Engineering Laboratory (CRREL), which proposes a high frequency radar to examine the shallower portion of the record down to approximately 60 meters, including the presence of near-surface crevasses. The radar proposed herein is most sensitive at depths below 60 meters and can depict deep bedrock and internal layers to a substantial fraction of the ice thickness.
9316564 Mayewski This award is for support for a three year program to provide a high resolution record of the Antarctic climate through the acquisition, analysis, and interpretation of records of atmospheric chemical deposition taken from three ice cores located at sites within or immediately adjacent to the Ross Ice Drainage System (RIDS). These cores include one from Taylor Dome, and two from West Antarctic locations identified as potential deep drilling sites for the WAISCORES program. Collection of the two West Antarctic cores is intended to be a lightweight dry-drilling operation to depths of ~ 200 m, which will provide records of > 2 kyr. Glaciochemical analyses will focus on the major cations and anions found in the antarctic atmosphere, plus methanesulfonic acid and selected measurements of the hydrogen ion, aluminum, iron, and silica. These analyses, and companion stable isotope and particle measurements to be carried out by other investigators require < 7% by volume of each core, leaving > 90% for other investigators and storage at the U.S. National Ice Core Laboratory. These records are intended to solve a variety of scientific objectives while also providing spatial sampling and reconnaissance for future U.S. efforts in West Antarctica. ***
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.