USAP-DC

{"dp_type": "Project", "free_text": "Isotope"}

[{"awards": "2302832 Reilly, Brendan", "bounds_geometry": "POLYGON((-70 -55,-67 -55,-64 -55,-61 -55,-58 -55,-55 -55,-52 -55,-49 -55,-46 -55,-43 -55,-40 -55,-40 -56.1,-40 -57.2,-40 -58.3,-40 -59.4,-40 -60.5,-40 -61.6,-40 -62.7,-40 -63.8,-40 -64.9,-40 -66,-43 -66,-46 -66,-49 -66,-52 -66,-55 -66,-58 -66,-61 -66,-64 -66,-67 -66,-70 -66,-70 -64.9,-70 -63.8,-70 -62.7,-70 -61.6,-70 -60.5,-70 -59.4,-70 -58.3,-70 -57.2,-70 -56.1,-70 -55))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 12 Jul 2023 00:00:00 GMT", "description": "The potential for future sea level rise from melting and collapse of Antarctic ice sheets and glaciers is concerning. We can improve our understanding of how water is exchanged between Antarctic ice sheets and the ocean by studying how ice sheets behaved in past climates, especially conditions that were similar to or warmer than those at present. For this project, the research team will document Antarctica\u0027s response across an interval when Earth transitioned from the warm Pliocene into the Pleistocene ice ages by combining marine and land evidence for glacier variations from sites near the Antarctic Peninsula, complimented by detailed work on timescales and fossil evidence for environmental change. An important goal is to test whether Antarctica\u0027s glaciers changed at the same time as glaciers in the Northern Hemisphere as Earth\u0027s most recent Ice Age intensified, or alternatively responded to regional climate forcing in the Southern Hemisphere. Eleven investigators from seven US institutions, as well as Argentine collaborators, will study new sediment cores from the International Ocean Discovery Program, as well as legacy cores from that program and on-land outcrops on James Ross Island. The group embraces a vertically integrated research program that allows high school, undergraduate, graduate, post-docs and faculty to work together on the same projects. This structure leverages the benefits of near-peer mentoring and the development of a robust collaborative research network while allowing all participants to take ownership of different parts of the project. All members of the team are firmly committed to attracting researchers from under-represented groups and will do this through existing channels as well as via co-creating programming that centers the perspectives of diverse students in conversations about sea-level rise and climate change.\r\n\r\nThe proposed research seeks to understand phasing between Northern and Southern Hemisphere glacier and climate changes, as a means to understand drivers and teleconnections. The dynamics of past Antarctic glaciation can be studied using the unique isotope geochemical and mineralogic fingerprints from glacial sectors tied to a well-constrained time model for the stratigraphic successions. The proposed work would further refine the stratigraphic context through coupled biostratigraphic and magnetostratigraphic work. The magnitude of iceberg calving and paths of icebergs will be revealed using the flux, geochemical and mineralogic signatures, and 40Ar/39Ar and U-Pb geochronology of ice-rafted detritus. These provenance tracers will establish which sectors of Antarctica\u0027s ice sheets are more vulnerable to collapse, and the timing and pacing of these events will be revealed by their stratigraphic context. Additionally, the team will work with Argentine collaborators to connect the marine and terrestrial records by studying glacier records intercalated with volcanic flows on James Ross Island. These new constraints will be integrated with a state of the art ice-sheet model to link changes in ice dynamics with their underlying causes. Together, these tight stratigraphic constraints, geochemical signatures, and ice-sheet model simulations will provide a means to compare to the global records of climate change, understand their primary drivers, and elucidate the role of the Antarctic ice sheet in a major, global climatic shift from the Pliocene into the Pleistocene.", "east": -40.0, "geometry": "POINT(-55 -60.5)", "instruments": null, "is_usap_dc": true, "keywords": "PALEOMAGNETISM; SEDIMENTS; Scotia Sea", "locations": "Scotia Sea", "north": -55.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e NEOGENE \u003e PLIOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e NEOGENE; PHANEROZOIC \u003e CENOZOIC", "persons": "Reilly, Brendan", "platforms": null, "repositories": null, "science_programs": null, "south": -66.0, "title": "Collaborative Research: Linking Marine and Terrestrial Sedimentary Evidence for Plio-pleistocene Variability of Weddell Embayment and Antarctic Peninsula Glaciation", "uid": "p0010424", "west": -70.0}, {"awards": "1644004 Trumble, Stephen; 1643575 Kanatous, Shane; 1644256 Costa, Daniel", "bounds_geometry": "POLYGON((-66.534369 -52.962091,-65.3857434 -52.962091,-64.2371178 -52.962091,-63.0884922 -52.962091,-61.9398666 -52.962091,-60.791241 -52.962091,-59.6426154 -52.962091,-58.4939898 -52.962091,-57.3453642 -52.962091,-56.1967386 -52.962091,-55.048113 -52.962091,-55.048113 -54.530129,-55.048113 -56.098167000000004,-55.048113 -57.666205000000005,-55.048113 -59.234243,-55.048113 -60.802281,-55.048113 -62.370319,-55.048113 -63.938357,-55.048113 -65.506395,-55.048113 -67.074433,-55.048113 -68.642471,-56.1967386 -68.642471,-57.3453642 -68.642471,-58.4939898 -68.642471,-59.6426154 -68.642471,-60.791241 -68.642471,-61.9398666 -68.642471,-63.0884922 -68.642471,-64.2371178 -68.642471,-65.3857434 -68.642471,-66.534369 -68.642471,-66.534369 -67.074433,-66.534369 -65.506395,-66.534369 -63.938356999999996,-66.534369 -62.370319,-66.534369 -60.802281,-66.534369 -59.234243,-66.534369 -57.666205,-66.534369 -56.098167000000004,-66.534369 -54.530129,-66.534369 -52.962091))", "dataset_titles": "Data from: Whiskers provide time-series of toxic and essential trace elements, Se:Hg molar ratios, and stable isotope values of an apex Antarctic predator, the leopard seal; Leopard Seal Diving behavior data; Leopard Seal movement data", "datasets": [{"dataset_uid": "200361", "doi": "https://doi.org/10.5061/dryad.ksn02v75b", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Data from: Whiskers provide time-series of toxic and essential trace elements, Se:Hg molar ratios, and stable isotope values of an apex Antarctic predator, the leopard seal", "url": "https://datadryad.org/stash/dataset/doi:10.5061%2Fdryad.ksn02v75b"}, {"dataset_uid": "601690", "doi": "10.15784/601690", "keywords": "Antarctica; Antarctic Peninsula; Biology; Body Mass; Cryosphere; Diving Behavior; Leopard Seal; Seals", "people": "Costa, Daniel", "repository": "USAP-DC", "science_program": null, "title": "Leopard Seal Diving behavior data", "url": "https://www.usap-dc.org/view/dataset/601690"}, {"dataset_uid": "601689", "doi": "10.15784/601689", "keywords": "Antarctica; Antarctic Peninsula; Biology; Body Mass; Cryosphere; Diving Behavior; Leopard Seal; Movement Data; Seals", "people": "Costa, Daniel", "repository": "USAP-DC", "science_program": null, "title": "Leopard Seal movement data", "url": "https://www.usap-dc.org/view/dataset/601689"}], "date_created": "Fri, 12 May 2023 00:00:00 GMT", "description": "This research project is a multidisciplinary effort that brings together a diverse team of scientists from multiple institutions together to understand the foraging behavior and physiology of leopard seals and their role in the Southern Ocean food web. The project will examine the physiology and behavior of leopard seals to in an effort to determine their ability to respond to potential changes in their habitat and foraging areas. Using satellite tracking devices the team will examine the movement and diving behavior of leopard seals and couple this information with measurements of their physiological capacity. The project will determine whether leopard seals- who feed on diverse range of prey- are built differently than their deep diving relatives the Weddell and elephant seal who feed on fish and squid. The team will also determine whether leopard seals are operating at or near their physiological capability to determine how much, if any, ?reserve capacity? they might have to forage and live in changing environments. A better understanding of their home ranges, movement patterns, and general behavior will also be informative to help in managing human-leopard seal interactions. The highly visual nature of the data and analysis for this project lends itself to public and educational display and outreach, particularly as they relate to the changing Antarctic habitats. The project will use the research results to educate the public on the unique physiological and ecological adaptations to extreme environments seen in diving marine mammals, including adaptations to exercise under low oxygen conditions and energy utilization, which affect and dictate the lifestyle of these exceptional organisms. The results of the project will also contribute to the broader understanding that may enhance the aims of managing marine living resources.\u003cbr/\u003e\u003cbr/\u003eThe leopard seal is an apex predator in the Antarctic ecosystem. This project seeks to better understand the ability of the leopard seal to cope with a changing environment. The project will first examine the foraging behavior and habitat utilization of leopard seals using satellite telemetry. Specifically, satellite telemetry tags will be used to obtain dive profiles and movement data for individuals across multiple years. Diet and trophic level positions across multiple temporal scales will then be determined from physiological samples (e.g., blood, vibrissae, blubber fatty acids, stable isotopes, fecal matter). Oceanographic data will be integrated with these measures to develop habitat models that will be used to assess habitat type, habitat utilization, habitat preference, and home range areas for individual animals. Diet composition for individual seals will be evaluated to determine whether specific animals are generalists or specialists. Second, the team will investigate the physiological adaptations that allow leopard seals to be apex predators and determine to what extent leopard seals are working at or near their physiological limit. Diving behavior and physiology of leopard seals will be evaluated (for instance the aerobic dive limit for individual animals and skeletal muscle adaptations will be determined for diving under hypoxic conditions). Data from time-depth recorders will be used to determine foraging strategies for individual seals, and these diving characteristics will be related to physiological variables (e.g., blood volume, muscle oxygen stores) to better understand the link between foraging behavior and physiology. The team will compare myoglobin storage in swimming muscles associated with both forelimb and hind limb propulsion and the use of anaerobic versus aerobic metabolic systems while foraging.", "east": -55.048113, "geometry": "POINT(-60.791241 -60.802281)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; movement patterns; Diving Behavior; MAMMALS; MARINE ECOSYSTEMS; Leopard Seal", "locations": "Antarctic Peninsula", "north": -52.962091, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Costa, Daniel; Trumble, Stephen J; Kanatous, Shane", "platforms": null, "repo": "Dryad", "repositories": "Dryad; USAP-DC", "science_programs": null, "south": -68.642471, "title": "Collaborative Research: Foraging Ecology and Physiology of the Leopard Seal", "uid": "p0010419", "west": -66.534369}, {"awards": "1745078 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": "Carbon-13 isotopic composition of atmospheric methane across Heinrich Stadials 1 and 5, and Dansgaard Oesgher Event 12, WAIS Divide Ice Core, Antarctica", "datasets": [{"dataset_uid": "601683", "doi": "10.15784/601683", "keywords": "Antarctica; Cryosphere; Methane; West Antarctic Ice Sheet", "people": "Riddell-Young, Benjamin", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Carbon-13 isotopic composition of atmospheric methane across Heinrich Stadials 1 and 5, and Dansgaard Oesgher Event 12, WAIS Divide Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601683"}], "date_created": "Mon, 01 May 2023 00:00:00 GMT", "description": "This project will develop methods to measure the ratios of carbon-13 to carbon-12, and heavy to light hydrogen in methane in air trapped in ice cores. The ratios of the different forms of carbon and hydrogen are \"fingerprints\" of different sources of this gas in the past--for example wetlands in the tropics versus methane frozen in the sea floor. Once the analysis method is developed, the measurements will be used to examine why methane changed abruptly in the past, both during the last ice age, and during previous warm periods. The data will be used to understand how methane sources like wildfires, methane hydrates, and wetlands respond to climate change. This information is needed to understand future risks of large changes in methane in the atmosphere as Earth warms. \u003cbr/\u003e\u003cbr/\u003eThe project involves two tasks. First, the investigators will build and test a gas extraction system for methane isotopic measurements using continuous flow methods, with the goal of equaling or bettering the precision attained by the few other laboratories that make these measurements. The system will be interfaced with existing mass spectrometers at Oregon State University. The system consists of a vacuum chamber and sequence of traps, purification columns, and furnaces that separate methane from other gases and convert it to carbon dioxide or hydrogen for mass spectrometry. Second, the team will measure the isotopic composition of methane across large changes in concentration associated with two past interglacial periods and during abrupt methane changes of the last ice age. These measurements will be used to understand if the main reason for these concentration changes is climate-driven changes in emissions from wetlands, or whether other sources are involved, for example methane hydrates or wildfires.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Ice Sheet; TRACE GASES/TRACE SPECIES; METHANE", "locations": "Antarctic Ice Sheet", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores", "uid": "p0010416", "west": -180.0}, {"awards": "1542723 Alexander, Becky", "bounds_geometry": "POINT(-112.05 -79.28)", "dataset_titles": "WAIS Divide ice core nitrate isotopes", "datasets": [{"dataset_uid": "601456", "doi": "10.15784/601456", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Chemistry; Ice Core Records; Nitrate; Nitrate Isotopes; WAIS Divide Ice Core; West Antarctic Ice Sheet", "people": "Alexander, Becky", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide ice core nitrate isotopes", "url": "https://www.usap-dc.org/view/dataset/601456"}], "date_created": "Mon, 13 Feb 2023 00:00:00 GMT", "description": "The Earth\u0027s atmosphere is a highly oxidizing medium. The abundance of oxidants such as ozone in the atmosphere strongly influences the concentrations of pollutants and greenhouse gases, with implications for human health and welfare. Because oxidants are not preserved in geological archives, knowledge of how oxidants have varied in the past under changing climate conditions is extremely limited. This award will measure a proxy for oxidant concentrations in a West Antarctic ice core over several major climate transitions over the past 50,000 years. These measurements will complement similar measurements from a Greenland ice core, which showed significant changes in atmospheric oxidants over major climate transitions covering this same time period. The addition of measurements from Antarctica will allow researchers to examine if the oxidant changes suggested by the Greenland ice core record are regional or global in scale. Knowledge of how oxidants vary naturally with climate will better inform predictions of the composition of the future atmosphere under a warming climate.\u003cbr/\u003e\u003cbr/\u003eThis award will support measurements of the isotopic composition of nitrate in a West Antarctic ice core as a proxy for oxidant concentrations in the past atmosphere. The nitrogen isotopes of nitrate provide information on the degree of preservation of nitrate in the ice core record, and thus aid in the interpretation of the observed variability in the observed nitrate concentrations and oxygen isotopes in ice core records. By providing information about the spatial scale of oxidant changes over abrupt climate change events during the last glacial period, this project may also improve our understanding of mechanisms driving these abrupt events. Insight from this project will prove valuable for forecasting the response of stratospheric circulation to climate change, which has large implications for climate feedbacks and tropospheric composition. In addition, the information gleaned from this project on the mechanisms and feedbacks during abrupt climate change events will help determine the likelihood of such rapid events occurring in the future, which would have dramatic impacts on humankind. This award will provide training for one graduate and one undergraduate student, and will support the development of a hands-on activity related to rapid climate change to be used at the annual Polar Science Weekend at the Pacific Science Center in Seattle, WA.", "east": -112.05, "geometry": "POINT(-112.05 -79.28)", "instruments": null, "is_usap_dc": true, "keywords": "Nitrate Isotopes; ICE CORE RECORDS; LABORATORY; WAIS divide", "locations": "WAIS divide", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Alexander, Becky", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.28, "title": "Measuring an Ice-core Proxy for Relative Oxidant Abundances over Glacial-interglacial and Rapid Climate changes in a West Antarctic Ice Core", "uid": "p0010403", "west": -112.05}, {"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. \u003cbr/\u003eTechnical 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. \u003cbr/\u003e\u003cbr/\u003eThe 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.\u003cbr/\u003eThe 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": "1644004 Trumble, Stephen", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Data from: Whiskers provide time-series of toxic and essential trace elements, Se:Hg molar ratios, and stable isotope values of an apex Antarctic predator, the leopard seal", "datasets": [{"dataset_uid": "200338", "doi": "doi:10.5061/dryad.ksn02v75b", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Data from: Whiskers provide time-series of toxic and essential trace elements, Se:Hg molar ratios, and stable isotope values of an apex Antarctic predator, the leopard seal", "url": "https://datadryad.org/stash/share/h6UwXvfhZG26jtPTtDqyXNMnx2UWknOqmv05EBz6A10"}], "date_created": "Tue, 06 Dec 2022 00:00:00 GMT", "description": "This research project is a multidisciplinary effort that brings together a diverse team of scientists from multiple institutions together to understand the foraging behavior and physiology of leopard seals and their role in the Southern Ocean food web. The project will examine the physiology and behavior of leopard seals to in an effort to determine their ability to respond to potential changes in their habitat and foraging areas. Using satellite tracking devices the team will examine the movement and diving behavior of leopard seals and couple this information with measurements of their physiological capacity. The project will determine whether leopard seals- who feed on diverse range of prey- are built differently than their deep diving relatives the Weddell and elephant seal who feed on fish and squid. The team will also determine whether leopard seals are operating at or near their physiological capability to determine how much, if any, ?reserve capacity? they might have to forage and live in changing environments. A better understanding of their home ranges, movement patterns, and general behavior will also be informative to help in managing human-leopard seal interactions. The highly visual nature of the data and analysis for this project lends itself to public and educational display and outreach, particularly as they relate to the changing Antarctic habitats. The project will use the research results to educate the public on the unique physiological and ecological adaptations to extreme environments seen in diving marine mammals, including adaptations to exercise under low oxygen conditions and energy utilization, which affect and dictate the lifestyle of these exceptional organisms. The results of the project will also contribute to the broader understanding that may enhance the aims of managing marine living resources.\u003cbr/\u003eThe leopard seal is an apex predator in the Antarctic ecosystem. This project seeks to better understand the ability of the leopard seal to cope with a changing environment. The project will first examine the foraging behavior and habitat utilization of leopard seals using satellite telemetry. Specifically, satellite telemetry tags will be used to obtain dive profiles and movement data for individuals across multiple years. Diet and trophic level positions across multiple temporal scales will then be determined from physiological samples (e.g., blood, vibrissae, blubber fatty acids, stable isotopes, fecal matter). Oceanographic data will be integrated with these measures to develop habitat models that will be used to assess habitat type, habitat utilization, habitat preference, and home range areas for individual animals. Diet composition for individual seals will be evaluated to determine whether specific animals are generalists or specialists. Second, the team will investigate the physiological adaptations that allow leopard seals to be apex predators and determine to what extent leopard seals are working at or near their physiological limit. Diving behavior and physiology of leopard seals will be evaluated (for instance the aerobic dive limit for individual animals and skeletal muscle adaptations will be determined for diving under hypoxic conditions). Data from time-depth recorders will be used to determine foraging strategies for individual seals, and these diving characteristics will be related to physiological variables (e.g., blood volume, muscle oxygen stores) to better understand the link between foraging behavior and physiology. The team will compare myoglobin storage in swimming muscles associated with both forelimb and hind limb propulsion and the use of anaerobic versus aerobic metabolic systems while foraging.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "MAMMALS; Stable Isotopes; Livingston Island", "locations": "Livingston Island", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Trumble, Stephen J", "platforms": null, "repo": "Dryad", "repositories": "Dryad", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Foraging Ecology and Physiology of the Leopard Seal", "uid": "p0010394", "west": -180.0}, {"awards": "2135696 Polito, Michael; 2135695 Emslie, Steven", "bounds_geometry": "POLYGON((-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70.8,-180 -71.6,-180 -72.4,-180 -73.2,-180 -74,-180 -74.8,-180 -75.6,-180 -76.4,-180 -77.2,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -77.2,160 -76.4,160 -75.6,160 -74.8,160 -74,160 -73.2,160 -72.4,160 -71.6,160 -70.8,160 -70,162 -70,164 -70,166 -70,168 -70,170 -70,172 -70,174 -70,176 -70,178 -70,-180 -70))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 28 Oct 2022 00:00:00 GMT", "description": "Stable isotope analyses of carbon and nitrogen (\u03b413C and \u03b415N) are commonly used to investigate animal migration, foraging locations and diet, especially in marine species that can travel over great distances. One other stable isotope, sulfur (\u03b434S), is not as commonly used but is increasingly being applied to refine and corroborate data obtained from carbon and nitrogen analyses. Collagen is one of the best tissues for these analyses as it is abundant in bone, preserves well, and can be easily extracted for analysis. In the Ross Sea region, the cold, dry environment has been conductive for the preservation of Ad\u00e9lie penguin (Pygoscelis adeliae) bones, feathers, eggshell and even mummified remains, at active and abandoned colonies that date from before the Last Glacial Maximum (\u003e45,000 yrs ago) through the Holocene. Most of these colonies are associated with one of three polynyas, or highly productive areas of open water surrounded by sea ice in the Ross Sea. Thus, this species is an excellent bioindicator for marine conditions, past and present, and its colonies have appeared and disappeared throughout this region with changing climate and sea ice regimes for millennia. Current warming trends are inducing relatively rapid ecological responses by this species and some of the largest colonies in the Ross Sea are likely to be abandoned in the next 50 years from rising sea level. The recently established Ross Sea Marine Protected Area aims to protect Ad\u00e9lie penguins and other species in this region from human impacts and knowledge on how this species responds to climate change, past and present, will support this goal. \r\n\r\nWe propose to investigate ecological responses in diet and foraging behavior of the Ad\u00e9lie penguin to known climatic events that occurred in the middle to late Holocene, specifically, before, during and after a warming period known as the penguin \u2018optimum\u2019 at 2000 - 4000 cal yr before present (BP). We will apply for the first time a suite of three stable isotope analyses (\u03b413C, \u03b415N, \u03b434S) on chick bones and feathers, as well as prey remains, from active and abandoned colonies in the Ross Sea. We will use existing tissue samples (~60-80 bones) collected by PI Emslie with NSF support since 2001 and supplement these with newly collected samples of bones and feathers in this project. We will conduct compound-specific isotope analyses of carbon on essential amino acids from collagen from a selected sample of 30-40 bones that span the past 5000 yrs to provide corroboratory information. We will apply three-dimensional Bayesian niche models and/or community metrics using R scripts in these analyses to identify isotopic \u2018signatures\u2019 of existing and past foraging grounds and polynyas used by Ad\u00e9lie penguins in the southern, central, and northern Ross Sea. This four-year study will the first of its kind to apply multiple stable isotope analyses to investigate a living species of seabird over millennia in a region where it still exists today. \r\n\r\nBroader Impacts:\r\nThe PIs are committed to public engagement and enhancement of K-12 education in the STEM sciences. Broader impacts of this research will include support and training for one Ph.D., two M.S., and eight undergraduate students in the Department of Biology and Marine Biology, and two M.A. students in the Watson School of Education at the University of North Carolina Wilmington (UNCW). The last two students will continue to expand on a detailed polar curriculum that was initiated in previous NSF grants for 2nd and 4th grade students, and most recently for 9-12th grade students now available on PI Emslie\u2019s website (www.uncw.edu/penguins). Additional curricula for K-12 students will be designed and tested in this project, which will include visitation to local K-12 schools. As in previous awards, we will focus on schools that serve historically under-represented groups in the sciences. We will work with the UNCW Center for Education in STEM Sciences to assess the efficacy of this new curricula. All curricula will be uploaded on the Educational Resource Commons website. Field work will include blogs and active question-answer sessions with students at these schools. We will continue to post project information and updates on PI Emslie\u2019s website and YouTube channel. Our partnership with tour ship companies will provide a platform for onboard lectures on the importance of scientific research as well as citizen science opportunities for another sector of the public. This proposal requires fieldwork in the Antarctic.\r\n", "east": -180.0, "geometry": "POINT(170 -74)", "instruments": null, "is_usap_dc": true, "keywords": "Climate Change; Adelie Penguin; Foraging Ecology; Ross Sea; PENGUINS; Holocene; Stable Isotopes", "locations": "Ross Sea", "north": -70.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Emslie, Steven; Lane, Chad S; Polito, Michael", "platforms": null, "repositories": null, "science_programs": null, "south": -78.0, "title": "Collaborative Research: Using Multiple Stable Isotopes to Investigate Middle to Late Holocene Ecological Responses by Adelie Penguins in the Ross Sea", "uid": "p0010388", "west": 160.0}, {"awards": "2037963 Smith, Heidi", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 11 Oct 2022 00:00:00 GMT", "description": "Glacial ice cores serve as a museum back in time, providing detailed records of past climatic conditions. In addition to chronological records such as temperature, chemistry and gas composition, ice provides a unique environment for preserving microbes and other biological materials through time. These microbes provide invaluable insight into the physiological capabilities necessary for survival in the Earths cryosphere and other icy planetary bodies, yet little is known about them. This award supports fundamental research into the activity of microbes in ice, and directly supports major research priorities regarding Antarctic biota identified in the 2015 National Academies of Sciences, Engineering, and Medicine report, A Strategic Vision for NSF Investments in Antarctic and Southern Ocean Research. The broader impacts of this work are that it will be relevant to researchers across paleoclimate and biological fields. It will support two early career researchers, a graduate and an undergraduate student who will conduct laboratory analyses, participate in outreach activities, publish papers in scientific journals and present at conferences. \r\n\r\nThis work will use previously collected ice cores to investigate englacial microbial activity from the Holocene back to the Last Glacial Maximum from the blue ice area of Taylor Glacier, Antarctica. The proposal identified making significant contributions to 1) investing how Antarctic organisms evolve and adapt to changing environment, 2) understanding how microbes alter the preservation of paleorecord-relevant gas and trace element information in ice cores, and 3) identifying microbial life in cores and their activity in relation to dust depositional events. Two recently developed complementary techniques (bio-orthogonal noncanonical amino acid tagging and deuterium isotope probing) in combination with Raman Confocal Microspectroscopy will be used to assess and quantify microbial activity in ice. During phase one of the project, these methods will be optimized using deaccessioned ice cores available at the National Science Foundations Ice Core Facility. In phase two, ice cores in a time series from the Taylor Glacier will be analyzed for geochemistry and microbial activity. Research results will provide a comprehensive view of englacial microbial communities, including their metabolic diversity and activity, and the effect of geochemical parameters on microbial assemblages from different climate periods. Given the dearth of information available on englacial microbial communities, the results of this research will be of particular significance.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "LABORATORY; paleoclimate; CAMP; Taylor Glacier; Microbiology; Microbial activity; Alaska; ICE CORE RECORDS", "locations": "CAMP; Alaska; Taylor Glacier", "north": null, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Smith, Heidi; Foreman, Christine; Dieser, Markus", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "Life in Ice: Probing Microbial Englacial Activity through Time", "uid": "p0010385", "west": null}, {"awards": "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; Cryosphere; CTD; d18O; NBP0001; NBP0702; NBP0901; NBP1901; NBP2002; Oceans; oxygen isotope; R/V Nathaniel B. Palmer; seawater isotope; Southern Ocean", "people": "Hennig, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020", "url": "https://www.usap-dc.org/view/dataset/601611"}], "date_created": "Wed, 21 Sep 2022 00:00:00 GMT", "description": "Estimating Antarctic ice sheet growth or loss is important to predicting future sea level rise. Such estimates rely on field measurements or remotely sensed based observations of the ice sheet surface, ice margins, and or ice shelves. This work examines the introduction of freshwater into the ocean to surrounding Antarctica to track meltwater from continental ice. Polar ice is depleted in two stable isotopes, 18O and D, deuterium, relative to Southern Ocean seawater and precipitation. Measurements of seawater isotopic composition in conjunction with precise observations of seawater temperature and salinity, will permit discrimination of freshwater derived from melting glacial ice from that derived from regional precipitation or sea ice melt.\u003cbr/\u003e\u003cbr/\u003eThis research describes an accepted method for determining rates and locations of meltwater entering the oceans from polar ice sheets. As isotopic and salinity perturbations are cumulative in many Antarctic coastal seas, the method allows for the detection of any marked acceleration in meltwater introduction in specific regions, using samples collected and analyzed over a period of years to decades. Impact of the project derives from use of an independent method capable of constraining knowledge about current ice sheet melt rates, their stability and potential impact on sea level rise. The project allows for sample collection taken from foreign vessels of opportunity sailing in Antarctic waters, and subsequent sharing and interpretation of data. Research partners include the U.S., Korea, China, New Zealand, the United Kingdom, and Germany. Participating collaborators will collect seawater samples for isotopic and salinity analysis at Stanford University. USAP cruises will concentrate on sampling the Ross Sea, and the West Antarctic. The work plan includes interpretation of isotopic data using box model and mixing curve analyses as well as using isotope enabled ROMS (Regional Ocean Modeling System) models. The broader impacts of the research will include development of an educational module that illustrates the scientific method and how ocean observations help society understand how Earth is changing.", "east": -101.0, "geometry": "POINT(-104.5 -74.5)", "instruments": null, "is_usap_dc": true, "keywords": "Meltwater inventory; Stable Isotopes; WATER TEMPERATURE; SALINITY; Oxygen Isotopes; 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": "1744562 Loose, Brice", "bounds_geometry": "POLYGON((-180 -71,-179.9 -71,-179.8 -71,-179.7 -71,-179.6 -71,-179.5 -71,-179.4 -71,-179.3 -71,-179.2 -71,-179.1 -71,-179 -71,-179 -71.7,-179 -72.4,-179 -73.1,-179 -73.8,-179 -74.5,-179 -75.2,-179 -75.9,-179 -76.6,-179 -77.3,-179 -78,-179.1 -78,-179.2 -78,-179.3 -78,-179.4 -78,-179.5 -78,-179.6 -78,-179.7 -78,-179.8 -78,-179.9 -78,180 -78,177.5 -78,175 -78,172.5 -78,170 -78,167.5 -78,165 -78,162.5 -78,160 -78,157.5 -78,155 -78,155 -77.3,155 -76.6,155 -75.9,155 -75.2,155 -74.5,155 -73.8,155 -73.1,155 -72.4,155 -71.7,155 -71,157.5 -71,160 -71,162.5 -71,165 -71,167.5 -71,170 -71,172.5 -71,175 -71,177.5 -71,-180 -71))", "dataset_titles": "Expedition Data of NBP1704; NBP1704 Expedition Data; PIPERS Noble Gases", "datasets": [{"dataset_uid": "601609", "doi": "10.15784/601609", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Mass Spectrometer; NBP1704; Noble Gas; Oceans; Ross Sea; R/V Nathaniel B. Palmer", "people": "Loose, Brice", "repository": "USAP-DC", "science_program": null, "title": "PIPERS Noble Gases", "url": "https://www.usap-dc.org/view/dataset/601609"}, {"dataset_uid": "200329", "doi": "", "keywords": null, "people": null, "repository": "MGDS", "science_program": null, "title": "Expedition Data of NBP1704", "url": "https://www.marine-geo.org/tools/entry/NBP1704"}, {"dataset_uid": "001363", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1704 Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1704"}], "date_created": "Wed, 14 Sep 2022 00:00:00 GMT", "description": "Near the Antarctic coast, polynyas are open-water regions where extreme heat loss in winter causes seawater to become cold, salty, and dense enough to sink into the deep sea. The formation of this dense water has regional and global importance because it influences the ocean current system. Polynya processes are also tied to the amount of sea ice formed, ocean heat lost to atmosphere, and atmospheric CO2 absorbed by the Southern Ocean. Unfortunately, the ocean-atmosphere interactions that influence the deep ocean water properties are difficult to observe directly during the Antarctic winter. This project will combine field measurements and laboratory experiments to investigate whether differences in the concentration of noble gasses (helium, neon, argon, xenon, and krypton) dissolved in ocean waters can be linked to environmental conditions at the time of their formation. If so, noble gas concentrations could provide insight into the mechanisms controlling shelf and bottom-water properties, and be used to reconstruct past climate conditions. Project results will contribute to the Southern Ocean Observing System (SOOS) theme of The Future and Consequences of Carbon Uptake in the Southern Ocean. The project will also train undergraduate and graduate students in environmental monitoring, and earth and ocean sciences methods. \u003cbr/\u003e\u003cbr/\u003eUnderstanding the causal links between Antarctic coastal processes and changes in the deep ocean system requires study of winter polynya processes. The winter period of intense ocean heat loss and sea ice production impacts two important Antarctic water masses: High-Salinity Shelf Water (HSSW), and Antarctic Bottom Water (AABW), which then influence the strength of the ocean solubility pump and meridional overturning circulation. To better characterize how sea ice cover, ocean-atmosphere exchange, brine rejection, and glacial melt influence the physical properties of AABW and HSSW, this project will analyze samples and data collected from two Ross Sea polynyas during the 2017 PIPERS winter cruise. Gas concentrations will be measured in seawater samples collected by a CTD rosette, from an underwater mass-spectrometer, and from a benchtop Membrane Inlet Mass Spectrometer. Noble gas concentrations will reveal the ocean-atmosphere (dis)equilibrium that exists at the time that surface water is transformed into HSSW and AABW, and provide a fingerprint of past conditions. In addition, nitrogen (N2), oxygen (O2), argon, and CO2 concentration will be used to determine the net metabolic balance, and to evaluate the efficacy of N2 as an alternative to O2 as glacial meltwater tracer. Laboratory experiments will determine the gas partitioning ratios during sea ice formation. Findings will be synthesized with PIPERS and related projects, and so provide an integrated view of the role of the wintertime Antarctic coastal system on deep water composition.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -179.0, "geometry": "POINT(168 -74.5)", "instruments": null, "is_usap_dc": true, "keywords": "Helium Isotopes; R/V NBP; DISSOLVED GASES; POLYNYAS; Ross Sea", "locations": "Ross Sea", "north": -71.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Loose, Brice", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "MGDS; R2R; USAP-DC", "science_programs": null, "south": -78.0, "title": "Measuring Dissolved Gases to Reveal the Processes that Drive the Solubility Pump and Determine Gas Concentration in Antarctic Bottom Water", "uid": "p0010376", "west": 155.0}, {"awards": "2123354 Conway, Timothy; 2123333 Fitzsimmons, Jessica; 2123491 John, Seth", "bounds_geometry": "POLYGON((-135 -66,-131.5 -66,-128 -66,-124.5 -66,-121 -66,-117.5 -66,-114 -66,-110.5 -66,-107 -66,-103.5 -66,-100 -66,-100 -67,-100 -68,-100 -69,-100 -70,-100 -71,-100 -72,-100 -73,-100 -74,-100 -75,-100 -76,-103.5 -76,-107 -76,-110.5 -76,-114 -76,-117.5 -76,-121 -76,-124.5 -76,-128 -76,-131.5 -76,-135 -76,-135 -75,-135 -74,-135 -73,-135 -72,-135 -71,-135 -70,-135 -69,-135 -68,-135 -67,-135 -66))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 08 Sep 2022 00:00:00 GMT", "description": "The goal of the international GEOTRACES program is to understand the distributions of trace chemical elements and their isotopes (TEIs) in the oceans. Many trace metals such as iron are essential for life and thus considered nutrients for phytoplankton growth, with trace metal cycling being especially important for influencing carbon cycling in the iron-limited Southern Ocean, where episodic supply of iron from a range of different external sources is important. The primary goal of this project is to measure the dissolved concentrations, size partitioning, and dissolved isotope signature of Fe on a transect of water-column stations throughout the Amundsen Sea and surrounding region of the Antarctic Margin, as part of the GP17-ANT Expedition. The secondary goal of this project is to analyze the concentrations and size partitioning of the trace metals manganese, zinc, copper, cadmium, nickel, and lead in all water-column samples, measure the isotope ratios of zinc, cadmium, nickel, and copper in a subset of water column samples, and measure the Fe isotopic signature of aerosols, porewaters, and particles. Observations from this project will be incorporated into regional and global biogeochemistry models to assess TEI cycling within the Amundsen Sea and implications for the wider Southern Ocean. This project spans three institutions, four graduate students, undergraduate students, and will provide ultrafiltered samples and data to other PIs as service.\r\n\r\nThe US GEOTRACES GP17 ANT expedition, planned for austral summer 2023/2024 aims to determine the distribution and cycling of trace elements and their isotopes in the Amundsen Sea Sector (100-135\u00b0W) of the Antarctic Margin. The cruise will follow the Amundsen Sea \u2018conveyor belt\u2019 by sampling waters coming from the Antarctic Circumpolar Current onto the continental shelf, including near the Dotson and Pine Island ice shelves, the productive Amundsen Sea Polynya (ASP), and outflowing waters. Episodic addition of dissolved Fe and other TEIs from dust, ice-shelves, melting ice, and sediments drive seasonal primary productivity and carbon export over the Antarctic shelf and offshore into Southern Ocean. Seasonal coastal polynyas such as the highly productive ASP thus act as key levers on global carbon cycling. However, field observations of TEIs in such regions remain scarce, and biogeochemical cycling processes are poorly captured in models of ocean biogeochemistry. The investigators will use their combined analytical toolbox, in collaboration with the diagnostic chemical tracers and regional models of other funded groups to address four main objectives: 1) What is the relative importance of different sources in supplying Fe and other TEIs to the ASP? 2) What is the physiochemical speciation of this Fe, and its potential for transport? 3) How do biological uptake, scavenging and regeneration in the ASP influence TEI distributions, stoichiometry, and nutrient limitation? 4) What is the flux and signature of TEIs transported offshore to the ACC and Southern Ocean?", "east": -100.0, "geometry": "POINT(-117.5 -71)", "instruments": null, "is_usap_dc": true, "keywords": "R/V NBP; Amundsen Sea; TRACE ELEMENTS; BIOGEOCHEMICAL CYCLES", "locations": "Amundsen Sea", "north": -66.0, "nsf_funding_programs": "Chemical Oceanography; Chemical Oceanography; Chemical Oceanography", "paleo_time": null, "persons": "Conway, Timothy; Fitzsimmons, Jessica; John, Seth", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repositories": null, "science_programs": null, "south": -76.0, "title": "Collaborative Research: US GEOTRACES GP17-ANT: Dissolved concentrations, isotopes, and colloids of the bioactive trace metals", "uid": "p0010374", "west": -135.0}, {"awards": "2002422 TBD", "bounds_geometry": null, "dataset_titles": "Clumped-isotope composition of molecular oxygen trapped in the Allan Hills S27 ice core", "datasets": [{"dataset_uid": "601593", "doi": "10.15784/601593", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Clumped-isotope composition of molecular oxygen trapped in the Allan Hills S27 ice core", "url": "http://www.usap-dc.org/view/dataset/601593"}], "date_created": "Tue, 02 Aug 2022 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Allan Hills; Antarctica; Cryosphere; Last Interglacial; Oxygen", "locations": "Allan Hills; Antarctica", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Banerjee, Asmita; Yan, Yuzhen; Yeung, Laurence", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": null, "title": null, "uid": null, "west": null}, {"awards": "2012444 Cimino, Megan; 2012247 Groff, Dulcinea; 2012365 Johnston, David", "bounds_geometry": "POLYGON((-65 -64.5,-64.8 -64.5,-64.6 -64.5,-64.4 -64.5,-64.2 -64.5,-64 -64.5,-63.8 -64.5,-63.6 -64.5,-63.4 -64.5,-63.2 -64.5,-63 -64.5,-63 -64.55,-63 -64.6,-63 -64.65,-63 -64.7,-63 -64.75,-63 -64.8,-63 -64.85,-63 -64.9,-63 -64.95,-63 -65,-63.2 -65,-63.4 -65,-63.6 -65,-63.8 -65,-64 -65,-64.2 -65,-64.4 -65,-64.6 -65,-64.8 -65,-65 -65,-65 -64.95,-65 -64.9,-65 -64.85,-65 -64.8,-65 -64.75,-65 -64.7,-65 -64.65,-65 -64.6,-65 -64.55,-65 -64.5))", "dataset_titles": null, "datasets": null, "date_created": "Sun, 24 Jul 2022 00:00:00 GMT", "description": "This award is funded in whole or part under the American Rescue Plan Act of 2021 (Public Law 117-2). \r\nPart I: Non-technical description: \r\nAdlie penguin colonies are declining and disappearing from the western Antarctic Peninsula. However, not all colonies in a certain area decline or disappear at the same rate. This research project will evaluate the influence of terrestrial surface properties on Adlie penguin colonies, leveraging five decades of research on seabirds near Palmer Station where an Adlie colony on Litchfield Island became extinct in 2007 while other colonies nearby are still present. The researchers will combine information obtained from remote sensing, UAS (Unoccupied Aircraft System, or drones) high-resolution maps, reconstruction of past moss banks and modeling with machine learning tools to define suitable penguin and peatbank moss habitats and explore the influence of microclimate on their distributions. In particular, the researchers are asking if guano from penguin colonies could act as fertilizers of moss banks in the presence of localized wind patters that can carry airborne nitrogen to the mosses. Modeling will relate penguin and peatbank moss spatial patterns to environmental variables and provide a greater understanding of how continued environmental change could impact these communities. The project allows for documentation of terrestrial Antarctic ecosystems in support of seabirds and provisioning of such information to the broader science community that seeks to study penguins, educating graduate and undergraduate students and a post-doctoral researcher. The research team includes two young women as Principal Investigators, one of them from an under-represented ethnic minority, first time Antarctic Principal Investigator, from an EPSCoR state (Wyoming), broadening participation in Antarctic research. Researchers will serve as student mentors through the Duke Bass Connections program entitled Biogeographic Assessment of Antarctic Coastal Habitats. This program supports an interdisciplinary team of graduate and undergraduate students collaborating with project faculty and experts on cutting-edge research bridging the classroom and the real world.\r\n\r\nPart II: Technical description: \r\nThis research aims to understand the changes at the microclimate scale (meters) by analyzing present and past Adlie penguin colonies and moss peatbanks in islands around Palmer Station in the western Antarctic Peninsula interlinked systems that are typically considered in isolation. By integrating in situ and remote data, this project will synthesize the drivers of biogeomorphology on small islands of the Antarctic Peninsula, a region of rapid change where plants and animals often co-occur and animal presence often determines the habitation of plants. A multi-disciplinary approach combine field measurements, remote sensing, UAS (Unoccupied Aircraft Systems) maps, paleoecology and modeling with machine learning to define suitable habitats and the influence of microclimates on penguin and peatbank distributions. The link between the two aspects of this study, peatbanks and penguins, is the potential source of nutrients for peat mosses from penguin guano. Peatbank and penguin distribution will be modeled and all models will be validated using in situ information from moss samples that will identify mechanistic processes. This project leverages 5 decades of seabird research in the area and high-definition remote sensing provided by the Polar Geospatial center to study the microclimate of Litchfield Island where an Adlie colony became extinct in 2007 when other colonies nearby are still present. The research team includes two early career women as Principal Investigators, one of them from an under-represented ethnic minority, first time Antarctic Principal Investigator, from an EPSCoR state (Wyoming). Researchers will serve as mentors for students through the Duke Bass Connections program entitled Biogeogrpahic Assessment of Antarctic Coastal Habitats which bridges the classroom and the real world.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -63.0, "geometry": "POINT(-64 -64.75)", "instruments": null, "is_usap_dc": true, "keywords": "Palmer Station; Antarctic Peninsula; COASTAL; STABLE ISOTOPES; TOPOGRAPHIC EFFECTS; PALEOCLIMATE RECONSTRUCTIONS; MACROFOSSILS; PLANTS; PENGUINS; ISOTOPES; VISIBLE IMAGERY; RADIOCARBON; Anvers Island", "locations": "Antarctic Peninsula; Anvers Island; Palmer Station", "north": -64.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Groff, Dulcinea; Cimino, Megan; Johnston, David", "platforms": null, "repositories": null, "science_programs": null, "south": -65.0, "title": "Collaborative Research: Common Environmental Drivers Determine the Occupation Chronology of Ad\u00e9lie Penguins and Moss Peatbanks on the Western Antarctic Peninsula", "uid": "p0010354", "west": -65.0}, {"awards": "1745068 Booth, Robert; 1745082 Beilman, David", "bounds_geometry": "POLYGON((-64.4 -62.4,-63.910000000000004 -62.4,-63.42 -62.4,-62.93000000000001 -62.4,-62.440000000000005 -62.4,-61.95 -62.4,-61.46 -62.4,-60.97 -62.4,-60.480000000000004 -62.4,-59.99 -62.4,-59.5 -62.4,-59.5 -62.7,-59.5 -63,-59.5 -63.3,-59.5 -63.6,-59.5 -63.900000000000006,-59.5 -64.2,-59.5 -64.5,-59.5 -64.80000000000001,-59.5 -65.10000000000001,-59.5 -65.4,-59.99 -65.4,-60.480000000000004 -65.4,-60.97 -65.4,-61.46 -65.4,-61.95 -65.4,-62.440000000000005 -65.4,-62.93000000000001 -65.4,-63.42 -65.4,-63.910000000000004 -65.4,-64.4 -65.4,-64.4 -65.10000000000001,-64.4 -64.80000000000001,-64.4 -64.5,-64.4 -64.2,-64.4 -63.900000000000006,-64.4 -63.6,-64.4 -63.3,-64.4 -63,-64.4 -62.7,-64.4 -62.4))", "dataset_titles": "LMG2002 Expedtition Data", "datasets": [{"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, 10 Jun 2022 00:00:00 GMT", "description": "Warming on the western Antarctic Peninsula in the later 20th century has caused widespread changes in the cryosphere (ice and snow) and terrestrial ecosystems. These recent changes along with longer-term climate and ecosystem histories will be deciphered using peat deposits. Peat accumulation can be used to assess the rate of glacial retreat and provide insight into ecological processes on newly deglaciated landscapes in the Antarctic Peninsula. This project builds on data suggesting recent ecosystem transformations that are linked to past climate of the western Antarctic Peninsula and provide a timeline to assess the extent and rate of recent glacial change. The study will produce a climate record for the coastal low-elevation terrestrial region, which will refine the major climate shifts of up to 6 degrees C in the recent past (last 12,000 years). A novel terrestrial record of the recent glacial history will provide insight into observed changes in climate and sea-ice dynamics in the western Antarctic Peninsula and allow for comparison with off-shore climate records captured in sediments. Observations and discoveries from this project will be disseminated to local schools and science centers. The project provides training and career development for a postdoctoral scientist as well as graduate and undergraduate students.\u003cbr/\u003e\u003cbr/\u003eThe research presents a new systematic survey to reconstruct ecosystem and climate change for the coastal low-elevation areas on the western Antarctic Peninsula (AP) using proxy records preserved in late Holocene peat deposits. Moss and peat samples will be collected and analyzed to generate a comprehensive data set of late-Holocene climate change and ecosystem dynamics. The goal is to document and understand the transformations of landscape and terrestrial ecosystems on the western AP during the late Holocene. The testable hypothesis is that coastal regions have experienced greater climate variability than evidenced in ice-core records and that past warmth has facilitated dramatic ecosystem and cryosphere response. A primary product of the project is a robust reconstruction of late Holocene climate changes for coastal low-elevation terrestrial areas using multiple lines of evidence from peat-based biological and geochemical proxies, which will be used to compare with climate records derived from marine sediments and ice cores from the AP region. These data will be used to test several ideas related to novel peat-forming ecosystems (such as Antarctic hairgrass bogs) in past warmer climates and climate controls over ecosystem establishment and migration to help assess the nature of the Little Ice Age cooling and cryosphere response. The chronology of peat cores will be established by radiocarbon dating of macrofossils and Bayesian modeling. The high-resolution time series of ecosystem and climate changes will help put the observed recent changes into a long-term context to bridge climate dynamics over different time scales.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -59.5, "geometry": "POINT(-61.95 -63.900000000000006)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; ISOTOPES; USAP-DC; PALEOCLIMATE RECONSTRUCTIONS; SEDIMENTS; FIELD INVESTIGATION; AMD/US; Antarctic Peninsula; AMD; TERRESTRIAL ECOSYSTEMS; USA/NSF; RADIOCARBON", "locations": "Antarctic Peninsula", "north": -62.4, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Beilman, David; Booth, Robert", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -65.4, "title": "Collaborative Research: Reconstructing Late Holocene Ecosystem and Climate Shifts from Peat Records in the Western Antarctic Peninsula", "uid": "p0010337", "west": -64.4}, {"awards": "1951090 Stukel, Michael", "bounds_geometry": "POLYGON((-80 -63,-78.2 -63,-76.4 -63,-74.6 -63,-72.8 -63,-71 -63,-69.2 -63,-67.4 -63,-65.6 -63,-63.8 -63,-62 -63,-62 -63.7,-62 -64.4,-62 -65.1,-62 -65.8,-62 -66.5,-62 -67.2,-62 -67.9,-62 -68.6,-62 -69.3,-62 -70,-63.8 -70,-65.6 -70,-67.4 -70,-69.2 -70,-71 -70,-72.8 -70,-74.6 -70,-76.4 -70,-78.2 -70,-80 -70,-80 -69.3,-80 -68.6,-80 -67.9,-80 -67.2,-80 -66.5,-80 -65.8,-80 -65.1,-80 -64.4,-80 -63.7,-80 -63))", "dataset_titles": "BCO-DMO Project Page", "datasets": [{"dataset_uid": "200294", "doi": null, "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "BCO-DMO Project Page", "url": "https://www.bco-dmo.org/project/838048"}], "date_created": "Fri, 03 Jun 2022 00:00:00 GMT", "description": "Algae in the surface ocean convert carbon dioxide into organic carbon through photosynthesis. The biological carbon pump transports this organic carbon from the atmosphere to the deep ocean where it can be stored for tens to hundreds of years. Annually, the amount transported is similar to that humans are currently emitting by burning fossil fuels. However, at present we cannot predict how this important process will change with a warming ocean. These investigators plan to develop a 15+ year time-series of vertical carbon transfer for the Western Antarctic Peninsula; a highly productive Antarctic ecosystem. This region is also rapid transition to warmer temperatures leading to reduced sea ice coverage. This work will help researchers better understand how the carbon cycle in the Western Antarctic Peninsula will respond to climate change. The researchers will develop the first large-scale time-series of carbon flux anywhere in the ocean. This research will also support the education and training of a graduate student and support the integration of concepts in Antarctic research into two undergraduate courses designed for non-science majors and advanced earth science students. The researchers will also develop educational modules for introducing elementary and middle-school age students to important concepts such as gross and net primary productivity, feedbacks in the marine and atmospheric systems, and the differences between correlation and causation. Results from this proposal will also be incorporated into a children?s book, ?Plankton do the Strangest Things?, that is targeted at 5-7 year olds and is designed to introduce them to the incredible diversity and fascinating adaptations of microscopic marine organisms.\u003cbr/\u003e\u003cbr/\u003e This research seeks to leverage 6 years (2015-2020) of 234Th samples collected on Palmer LTER program, 5 years of prior measurements (2009-2010, 2012-2014), and upcoming cruises (2021-2023) to develop a time-series of summertime particle flux in the WAP that stretches for 15 years. The 238U-234Th disequilibrium approach utilizes changes in the activity of the particle-active radio-isotope 234Th relative to its parent nuclide 238U to quantify the flux of sinking carbon out of the surface ocean (over a time-scale of ~one month). This proposal will fund 234Th analyses from nine years? worth of cruises (2015-2023) and extensive analyses designed to investigate the processes driving inter-annual variability in the BCP. These include: 1) physical modeling to quantify the importance of advection and diffusion in the 234Th budget, 2) time-series analyses of particle flux, and 3) statistical modeling of the relationships between particle flux and multiple presumed drivers (biological, chemical, physical, and climate indices) measured by collaborators in the Palmer LTER program. This multi-faceted approach is critical for linking the measurements to models and for predicting responses to climate change. It will also test the hypothesis that export flux is decreasing in the northern WAP, increasing in the southern WAP, and increasing when integrated over the entire region as a result of earlier sea ice retreat and a larger ice-free zone. The project will also investigate relationships between carbon export and multiple potentially controlling factors including: primary productivity, algal biomass and taxonomic composition, biological oxygen saturation, zooplankton biomass and taxonomic composition, bacterial production, temperature, wintertime sea ice extent, date of sea ice retreat, and climate modes.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -62.0, "geometry": "POINT(-71 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; AMD/US; FIELD INVESTIGATION; Palmer Station; USAP-DC; BIOGEOCHEMICAL CYCLES; USA/NSF", "locations": "Palmer Station", "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Stukel, Michael", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -70.0, "title": "Quantifying Processes Driving Interannual Variability in the Biological Carbon Pump in the Western Antarctic Peninsula", "uid": "p0010332", "west": -80.0}, {"awards": "2141555 Brooks, Cassandra", "bounds_geometry": "POLYGON((-180 -71.5,-177.1 -71.5,-174.2 -71.5,-171.3 -71.5,-168.4 -71.5,-165.5 -71.5,-162.6 -71.5,-159.7 -71.5,-156.8 -71.5,-153.9 -71.5,-151 -71.5,-151 -72.25,-151 -73,-151 -73.75,-151 -74.5,-151 -75.25,-151 -76,-151 -76.75,-151 -77.5,-151 -78.25,-151 -79,-153.9 -79,-156.8 -79,-159.7 -79,-162.6 -79,-165.5 -79,-168.4 -79,-171.3 -79,-174.2 -79,-177.1 -79,180 -79,178.1 -79,176.2 -79,174.3 -79,172.4 -79,170.5 -79,168.6 -79,166.7 -79,164.8 -79,162.9 -79,161 -79,161 -78.25,161 -77.5,161 -76.75,161 -76,161 -75.25,161 -74.5,161 -73.75,161 -73,161 -72.25,161 -71.5,162.9 -71.5,164.8 -71.5,166.7 -71.5,168.6 -71.5,170.5 -71.5,172.4 -71.5,174.3 -71.5,176.2 -71.5,178.1 -71.5,-180 -71.5))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 27 May 2022 00:00:00 GMT", "description": "The Ross Sea, Antarctica, is one of the last large intact marine ecosystems left in the world, yet is facing increasing pressure from commercial fisheries and environmental change. It is the most productive stretch of the Southern Ocean, supporting an array of marine life, including Antarctic toothfish the regions top fish predator. While a commercial fishery for toothfish continues to grow in the Ross Sea, fundamental knowledge gaps remain regarding toothfish ecology and the impacts of toothfish fishing on the broader Ross Sea ecosystem. Recognizing the global value of the Ross Sea, a large (\u003e2 million km2) marine protected area was adopted by the multi-national Commission for the Conservation of Antarctic Marine Living Resources in 2016. This research will fill a critical gap in the knowledge of Antarctic toothfish and deepen understanding of biological-physical interactions for fish ecology, while contributing to knowledge of impacts of fishing and environmental change on the Ross Sea system. This work will further provide innovative tools for studying connectivity among geographically distinct fish populations and for synthesizing and assessing the efficacy of a large-scale marine protected area. In developing an integrated research and education program in engaged scholarship, this project seeks to train the next generation of scholars to engage across the science-policy-public interface, engage with Southern Ocean stakeholders throughout the research process, and to deepen the publics appreciation of the Antarctic. \r\n\r\nA major research priority among Ross Sea scientists is to better understand the life history of the Antarctic toothfish and test the efficacy of the Ross Sea Marine Protected Area (MPA) in protecting against the impacts of overfishing and climate change. Like growth rings of a tree, fish ear bones, called otoliths, develop annual layers of calcium carbonate that incorporates elements from their environment. Otoliths offer information on the fishs growth and the surrounding ocean conditions. Hypothesizing that much of the Antarctic toothfish life cycle is structured by ocean circulation, this research employs a multi-disciplinary approach combining age and growth work with otolith chemistry testing, while also utilizing GIS mapping. The project will measure life history parameters as well as trace elements and stable isotopes in otoliths in three distinct sets collected over the last four decades in the Ross Sea. The information will be used to quantify the transport pathways Antarctic toothfish use across their life history, and across time, in the Ross Sea. The project will assess if toothfish populations from the Ross Sea are connected more widely across the Antarctic. By comparing life history and otolith chemistry data across time, the researchers will assess change in life history parameters and spatial dynamics and seek to infer if these changes are driven by fishing or climate change. Spatially mapping of these data will allow an assessment of the efficacy of the Ross Sea MPA in protecting toothfish and where further protections might be needed.\r\n\r\nThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": -151.0, "geometry": "POINT(-175 -75.25)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; FIELD INVESTIGATION; AMD/US; USAP-DC; AMD; FISHERIES; Ross Sea", "locations": "Ross Sea", "north": -71.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Brooks, Cassandra", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": -79.0, "title": "CAREER: Using Otolith Chemistry to Reveal the Life History of Antarctic Toothfish in the Ross Sea, Antarctica: Testing Fisheries and Climate Change Impacts on a Top Fish Predator", "uid": "p0010329", "west": 161.0}, {"awards": "2019719 Brook, Edward J.", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "2022-23 Allan Hills Intermediate Ice Core Site Selection Field Report; Replicate O-17-excess by continuous flow laser spectroscopy for an ice core section at Summit, Greenland", "datasets": [{"dataset_uid": "601697", "doi": "10.15784/601697", "keywords": "Allan Hills; Antarctica; ApRES; Cryosphere; Ice Core; Ice Penetrating Radar; Temperature Profiles", "people": "Conway, Howard; Brook, Edward", "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": "601659", "doi": "10.15784/601659", "keywords": "Antarctica; Continuous Flow; Cryosphere; Glaciology; Greenland; Ice Core Data; Laser Spectroscopy; Oxygen Isotopes; Triple Oxygen Isotopes", "people": "Davidge, Lindsey", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "Replicate O-17-excess by continuous flow laser spectroscopy for an ice core section at Summit, Greenland", "url": "https://www.usap-dc.org/view/dataset/601659"}], "date_created": "Sat, 21 May 2022 00:00:00 GMT", "description": "Cores drilled through the Antarctic ice sheet provide a remarkable window on the evolution of Earth\u2019s climate and unique samples of the ancient atmosphere. The clear link between greenhouse gases and climate revealed by ice cores underpins much of the scientific understanding of climate change. Unfortunately, the existing data do not extend far enough back in time to reveal key features of climates warmer than today. COLDEX, the Center for Oldest Ice Exploration, will solve this problem by exploring Antarctica for sites to collect the oldest possible record of past climate recorded in the ice sheet. COLDEX will provide critical information for understanding how Earth\u2019s near-future climate may evolve and why climate varies over geologic time. New technologies will be developed for exploration and analysis that will have a long legacy for future research. An archive of old ice will stimulate new research for the next generations of polar scientists. COLDEX programs will galvanize that next generation of polar researchers, bring new results to other scientific disciplines and the public, and help to create a more inclusive and diverse scientific community.\r\n\r\nKnowledge of Earth\u2019s climate history is grounded in the geologic record. This knowledge is gained by measuring chemical, biological and physical properties of geologic materials that reflect elements of climate. Ice cores retrieved from polar ice sheets play a central role in this science and provide the best evidence for a strong link between atmospheric carbon dioxide and climate on geologic timescales. The goal of COLDEX is to extend the ice-core record of past climate to at least 1.5 million years by drilling and analyzing a continuous ice core in East Antarctica, and to much older times using discontinuous ice sections at the base and margin of the ice sheet. COLDEX will develop and deploy novel radar and melt-probe tools to rapidly explore the ice, use ice-sheet models to constrain where old ice is preserved, conduct ice coring, develop new analytical systems, and produce novel paleoclimate records from locations across East Antarctica. The search for Earth\u2019s oldest ice also provides a compelling narrative for disseminating information about past and future climate change and polar science to students, teachers, the media, policy makers and the public. COLDEX will engage and incorporate these groups through targeted professional development workshops, undergraduate research experiences, a comprehensive communication program, annual scientific meetings, scholarships, and broad collaboration nationally and internationally. COLDEX will provide a focal point for efforts to increase diversity in polar science by providing field, laboratory, mentoring and networking experiences for students and early career scientists from groups underrepresented in STEM, and by continuous engagement of the entire COLDEX community in developing a more inclusive scientific culture.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; COLDEX; AMD; Antarctica; USAP-DC; FIELD SURVEYS; ICE DEPTH/THICKNESS; AMD/US", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Neff, P.; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "COLDEX", "south": -90.0, "title": "Center for Oldest Ice Exploration", "uid": "p0010321", "west": -180.0}, {"awards": "1443557 Isbell, John", "bounds_geometry": "POLYGON((-180 -85,-177.1 -85,-174.2 -85,-171.3 -85,-168.4 -85,-165.5 -85,-162.6 -85,-159.7 -85,-156.8 -85,-153.9 -85,-151 -85,-151 -85.2,-151 -85.4,-151 -85.6,-151 -85.8,-151 -86,-151 -86.2,-151 -86.4,-151 -86.6,-151 -86.8,-151 -87,-153.9 -87,-156.8 -87,-159.7 -87,-162.6 -87,-165.5 -87,-168.4 -87,-171.3 -87,-174.2 -87,-177.1 -87,180 -87,179 -87,178 -87,177 -87,176 -87,175 -87,174 -87,173 -87,172 -87,171 -87,170 -87,170 -86.8,170 -86.6,170 -86.4,170 -86.2,170 -86,170 -85.8,170 -85.6,170 -85.4,170 -85.2,170 -85,171 -85,172 -85,173 -85,174 -85,175 -85,176 -85,177 -85,178 -85,179 -85,-180 -85))", "dataset_titles": "A LITHOFACIES ANALYSIS OF A SOUTH POLAR GLACIATION IN THE EARLY PERMIAN: PAGODA FORMATION, SHACKLETON GLACIER REGION, ANTARCTICA; A new stratigraphic framework built on U-Pb single-zircon TIMS agesand implications for the timing ofthe penultimate icehouse (Paran\u00e1 Basin, Brazil); Constraining late Paleozoic ice extent in the Paganzo Basin of western Argentina utilizing U-Pb detrital zircon geochronology for the lower Paganzo Group strata; Coupled stratigraphic and U-Pb zircon age constraints on the late Paleozoic icehouse-to-greenhouse turnover in south-central Gondwana; Isotopes to ice: Constraining provenance of glacial deposits and ice centers in west-central Gondwana; Late Permian soil-forming paleoenvironments on Gondwana: A review; Provenance of late Paleozoic glacial/post-glacial deposits in the eastern Chaco-Paran\u00e1 Basin, Uruguay and southernmost Paran\u00e1 Basin, Brazil; Supplemental material: Nitrogen-fixing symbiosis inferred from stable isotope analysis of fossil tree rings from the Oligocene of Ethiopia; When does large woody debris influence ancient rivers? Dendrochronology\r\napplications in the Permian and Triassic, Antarctica", "datasets": [{"dataset_uid": "200267", "doi": "10.1016/j.palaeo.2021.110762", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Late Permian soil-forming paleoenvironments on Gondwana: A review", "url": "https://www.sciencedirect.com/science/article/abs/pii/S0031018221005472?via%3Dihub"}, {"dataset_uid": "200266", "doi": "10.2110/jsr.2021.004", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "A LITHOFACIES ANALYSIS OF A SOUTH POLAR GLACIATION IN THE EARLY PERMIAN: PAGODA FORMATION, SHACKLETON GLACIER REGION, ANTARCTICA", "url": "https://www.sepm.org/publications"}, {"dataset_uid": "200273", "doi": "10.1016/j.palaeo.2018.04.020", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Isotopes to ice: Constraining provenance of glacial deposits and ice centers in west-central Gondwana", "url": "https://www.sciencedirect.com/science/article/abs/pii/S0031018217309008?via%3Dihub"}, {"dataset_uid": "200274", "doi": "10.1130/G39213.1", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Supplemental material: Nitrogen-fixing symbiosis inferred from stable isotope analysis of fossil tree rings from the Oligocene of Ethiopia", "url": "https://pubs.geoscienceworld.org/gsa/geology/article-standard/45/8/687/207623/Nitrogen-fixing-symbiosis-inferred-from-stable"}, {"dataset_uid": "200272", "doi": "10.1016/j.jsames.2020.102899", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Constraining late Paleozoic ice extent in the Paganzo Basin of western Argentina utilizing U-Pb detrital zircon geochronology for the lower Paganzo Group strata", "url": "https://www.sciencedirect.com/science/article/pii/S0895981120304429?via%3Dihub#mmc1"}, {"dataset_uid": "200271", "doi": "10.1016/j.palaeo.2019.109544", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "When does large woody debris influence ancient rivers? Dendrochronology\r\napplications in the Permian and Triassic, Antarctica", "url": "https://www.sciencedirect.com/science/article/abs/pii/S0031018219304006?via%3Dihub"}, {"dataset_uid": "200270", "doi": "10.1016/j.jsames.2020.102989", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Provenance of late Paleozoic glacial/post-glacial deposits in the eastern Chaco-Paran\u00e1 Basin, Uruguay and southernmost Paran\u00e1 Basin, Brazil", "url": "https://www.sciencedirect.com/science/article/pii/S0895981120305320#mmc1"}, {"dataset_uid": "200269", "doi": "10.1130/G46740.1", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Coupled stratigraphic and U-Pb zircon age constraints on the late Paleozoic icehouse-to-greenhouse turnover in south-central Gondwana", "url": "https://gsapubs.figshare.com/articles/journal_contribution/Supplemental_material_Coupled_stratigraphic_and_U-Pb_zircon_age_constraints_on_the_late_Paleozoic_icehouse-to-greenhouse_turnover_in_south-central_Gondwana/12542069"}, {"dataset_uid": "200268", "doi": "10.1130/B31775.1.", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "A new stratigraphic framework built on U-Pb single-zircon TIMS agesand implications for the timing ofthe penultimate icehouse (Paran\u00e1 Basin, Brazil)", "url": "https://gsapubs.figshare.com/articles/journal_contribution/Supplemental_material_A_new_stratigraphic_framework_built_on_U-Pb_single-zircon_TIMS_ages_and_implications_for_the_timing_of_the_penultimate_icehouse_Paran_Basin_Brazil_/12535916"}], "date_created": "Fri, 31 Dec 2021 00:00:00 GMT", "description": "The research focus of this collaborative proposal was to collect fossil plants, fossil wood, stratigraphic, sedimentologic, paleosol, and geochemical data from plants and the rocks that contain them in order to reconstruct the extent of the Gondwana glaciation in the Shackleton Glacier (SHK) area, the invasion and subsequent flourishing of life following glacial retreat, changes to the physical environment, and the eventual recovery of plant life after the Late Permian biotic events. Only in Antarctica does a complete polar-to-near-polar succession occur across this climatic and biologic transition. The SHK is an important one as it is one of the few regions in the world where the Permian-Triassic boundary (PTB) is exposed within terrestrial rocks. In addition, outcrops in the SHK area extend from the glacigenic deposits of the Upper Carboniferous-Lower Permian through to the Upper Triassic and thus record ecosystems and the plants that inhabited them from the Gondwana icehouse into the Late Permian-Early Triassic greenhouse and into presumed \"full recovery\" of floras from the PTB extinctions in the Late Triassic.\r\n\r\nThe project encompassed a multidisciplinary plan that used various types of paleobotanical expertise, integrated with detailed sedimentology, stratigraphy, and geochemistry, in order to reconstruct Permian-Triassic plant communities and their paleoenvironments. This interdisciplinary approach is a powerful tool to uncover details of Antarctica\u2019s complex late Paleozoic and Mesozoic environmental, climatic, and biotic history which included: 1) glaciation/deglaciation, 2) development and evolution of a post-glacial landscape and biota, 3) environmental and biotic change associated with the end-Permian mass extinction events, 4) earliest ecosystems in the Triassic, 5) greenhouse conditions in the Triassic, 6) full \u2019recovery\u2019 of floras and ecosystems by the Late Triassic, and, through all of these events, 7) development and changes in a foreland basin system. Three interrelated focus areas, each delimited by distinct hypotheses and action strategies, provided the framework to trace floral diversity and environmental evolution after the retreat of glaciers through to the Late Triassic. Antarctica is the only place on Earth that includes extensive outcrops of high-paleolatitude terrestrial rocks, combined with widespread and well-preserved plant fossils, and that spans this crucial time.\r\n\r\nThe research and broader impacts of this proposal were integrated into action strategies that have been successful in the past. Compression floras were collected (constrained by stratigraphy) both quantitatively and qualitatively in order to obtain biodiversity and abundance data, and as a data source for paleoecological analysis. Even in formations where megafossils were unknown (e.g., Lower Permian), fossil wood is present so that anatomy and geochemistry of tree rings were examined. Standard sedimentologic and stratigraphic analyses were performed, as well as paleosol analyses, including mineralogic and major- and trace-element geochemistry. Collections will also be made for U-Pb zircon geochronology to better constrain geologic and biotic events.\r\n\r\nThe Broader Impacts of the project involved education and outreach initiatives that included women and under-represented groups in the excitement of Antarctic earth sciences: 1) Continuing successful public outreach, teaching, and mentoring of women and under-represented students in Antarctic research; 2) Participation in workshops for under-represented groups via the Expanding Your Horizons Program in Kansas, the TRIO program (KU), and the STELAR summer workshop (UWM) for high-school students. 3) Outreach via the KU Natural History Museum; 4) Exploring Antarctic geosciences through continued presentations to pre K-12 school groups, and field and lab activities at UWM, as well as links from McMurdo Station and satellite conferences from the field with K-12 science classes in Wisconsin and Illinois.", "east": 170.0, "geometry": "POINT(-170.5 -86)", "instruments": null, "is_usap_dc": true, "keywords": "Shackleton Glacier; SEDIMENTARY ROCKS; GLACIATION", "locations": "Shackleton Glacier", "north": -85.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Isbell, John", "platforms": null, "repo": "Publication", "repositories": "Publication", "science_programs": null, "south": -87.0, "title": "Collaborative Research: Permian and Triassic Icehouse to Greenhouse Paleoenvironments and Paleobotany in the Shackleton Glacier Area, Antarctica", "uid": "p0010287", "west": -151.0}, {"awards": "1644094 Caffee, Marc; 1644128 Welten, Kees", "bounds_geometry": "POINT(-112.12 -79.48)", "dataset_titles": "WAIS Divide Core 10Be data, 2850-3240 m", "datasets": [{"dataset_uid": "601692", "doi": "10.15784/601692", "keywords": "10Be; Antarctica; Beryllium; Cosmogenic Radionuclides; Cryosphere; Ice Core Data; WAIS divide", "people": "Woodruff, Thomas; Caffee, Marc; Welten, Kees", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Core 10Be data, 2850-3240 m", "url": "https://www.usap-dc.org/view/dataset/601692"}], "date_created": "Mon, 15 Nov 2021 00:00:00 GMT", "description": "The award supports a project to use existing samples from the West Antarctic Ice Sheet (WAIS) Divide ice core to align its timescale with that of the Greenland ice cores using common chronological markers. The upper 2850 m of the WAIS Divide core, which was drilled to a depth of 3405 m, has been dated with high precision. The timescale of the remaining (bottom) 550 m of the core has larger uncertainties, limiting our understanding of the timing of abrupt climate events in Antarctica relative to those in Greenland during the last ice age. The intellectual merit of this project is to further constrain the relative timing of these abrupt climate events in Greenland and Antarctica to obtain crucial insight into the underlying mechanism. The main objective of this project is to improve the current timescale of the WAIS Divide core from 31,000 to 65,000 years ago by synchronizing this core with the Greenland ice cores using common signals in Beryllium-10, a radioactive isotope of Be that is produced in the atmosphere by cosmic rays and is deposited onto the snow within 1-2 years of its production. The 10Be flux is largely independent of climate signals since its production varies with solar activity and the geomagnetic field. This project will further strengthen collaborations between the PI\u2019s in Berkeley and Purdue with ice core researchers in the US and Europe, involve undergraduate students in many aspects of its research, and continue out-reach to under-represented students.\r\n\r\nThe direct ice-to-ice synchronization of the WAIS Divide ice core with the Greenland Ice Core Chronology (GICC05) using cosmogenic 10Be is expected to reduce the uncertainty in the relative timing of more than 20 abrupt climate events in Greenland and Antarctica to a few decades. To achieve this goal we will obtain a continuous high-resolution record of 10Be in the WAIS Divide core from 2850 to 3390 m depth, and compare the obtained 10Be record with existing 10Be records of the Greenland ice cores, including GISP2 and NGRIP. We will separate 10Be from ~1000 ice samples of the WAIS Divide core and measure the 10Be concentration in each sample using accelerator mass spectrometry (AMS). Broader impacts of the 10Be measurements are that they will also provide information on the Laschamp event, a ~2000 year long period of low geomagnetic field strength around 41,000 years ago, and improve the calibration of the 14C dating method for organic samples older than 30,000 years. The broader impacts of the project include (1) the involvement and training of undergraduate students in ice core research and accelerator mass spectrometry measurements, (2) the incorporation of ice core and climate research into ongoing outreach programs at Purdue University and Berkeley SSL, (3) better understanding of abrupt climate changes in the past will improve our ability to predict future climate change, (4) evaluating the possible threat of a future geomagnetic excursion in the next few hundred years. This award does not require support in Antarctica.\r\n", "east": -112.12, "geometry": "POINT(-112.12 -79.48)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; LABORATORY; AMD/US; WAIS divide; AMD; USAP-DC; DEPTH AT SPECIFIC AGES", "locations": "WAIS divide", "north": -79.48, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Welten, Kees; Caffee, Marc", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.48, "title": "Synchronizing the WAIS Divide and Greenland Ice Cores from 30-65 ka BP using high-resolution 10Be measurements", "uid": "p0010280", "west": -112.12}, {"awards": "1643394 Buizert, Christo", "bounds_geometry": "POLYGON((-180 -65,-144 -65,-108 -65,-72 -65,-36 -65,0 -65,36 -65,72 -65,108 -65,144 -65,180 -65,180 -67.5,180 -70,180 -72.5,180 -75,180 -77.5,180 -80,180 -82.5,180 -85,180 -87.5,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.5,-180 -85,-180 -82.5,-180 -80,-180 -77.5,-180 -75,-180 -72.5,-180 -70,-180 -67.5,-180 -65))", "dataset_titles": "Antarctica 40,000 Year Temperature and Elevation Reconstructions; GISP2 and WAIS Divide Ice Cores 60,000 Year Surface Temperature Reconstructions; WAIS Divide 67-6ka nssS Data and EDML, EDC and TALDICE Volcanic Tie Points", "datasets": [{"dataset_uid": "200255", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Antarctica 40,000 Year Temperature and Elevation Reconstructions", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/32632"}, {"dataset_uid": "200257", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "GISP2 and WAIS Divide Ice Cores 60,000 Year Surface Temperature Reconstructions", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/34133"}, {"dataset_uid": "200256", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "WAIS Divide 67-6ka nssS Data and EDML, EDC and TALDICE Volcanic Tie Points", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/24530"}], "date_created": "Wed, 10 Nov 2021 00:00:00 GMT", "description": "This award supports a project to use ice cores to study teleconnections between the northern hemisphere, tropics, and Antarctica during very abrupt climate events that occurred during the last ice age (from 70,000 to 11,000 years ago). The observations can be used to test scientific theories about the role of the westerly winds on atmospheric carbon dioxide. In a warming world, snow fall in Antarctica is expected to increase, which can reduce the Antarctic contribution to sea level rise, all else being equal. The study will investigate how snow fall changed in the past in response to changes in temperature and atmospheric circulation, which can help improve projections of future sea level rise. Antarctica is important for the future evolution of our planet in several ways; it has the largest inventory of land-based ice, equivalent to about 58 m of global sea level and currently contributes about 0.3 mm per year to global sea level rise, which is expected to increase in the future due to global warming. The oceans surrounding Antarctica help regulate the uptake of human-produced carbon dioxide. Shifts in the position and strength of the southern hemisphere westerly winds could change the amount of carbon dioxide that is absorbed by the ocean, which will influence the rate of global warming. The climate and winds near and over Antarctica are linked to the rest of our planet via so-called climatic teleconnections. This means that climate changes in remote places can influence the climate of Antarctica. Understanding how these climatic teleconnections work in both the ocean and atmosphere is an important goal of climate research. The funds will further contribute towards training of a postdoctoral researcher and an early-career researcher; outreach to public schools; and the communication of research findings to the general public via the media, local events, and a series of Wikipedia articles.\r\n\r\nThe project will help to fully characterize the timing and spatial pattern of millennial-scale Antarctic climate change during the deglaciation and Dansgaard-Oeschger (DO) cycles using multiple synchronized Antarctic ice cores. The phasing of Antarctic climate change relative to Greenland DO events can distinguish between fast atmospheric teleconnections on sub-decadal timescales, and slow oceanic ones on centennial time scales. Preliminary work suggests that the spatial pattern of Antarctic change can fingerprint specific changes to the atmospheric circulation; in particular, the proposed work will clarify past movements of the Southern Hemisphere westerly winds during the DO cycle, which have been hypothesized. The project will help resolve a discrepancy between two previous seminal studies on the precise timing of interhemispheric coupling between ice cores in both hemispheres. The study will further provide state-of-the-art, internally-consistent ice core chronologies for all US Antarctic ice cores, as well as stratigraphic ties that can be used to integrate them into a next-generation Antarctic-wide ice core chronological framework. Combined with ice-flow modeling, these chronologies will be used for a continent-wide study of the relationship between ice sheet accumulation and temperature during the last deglaciation.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "AMD/US; ISOTOPES; Antarctica; USA/NSF; AMD; ICE CORE RECORDS; USAP-DC; VOLCANIC DEPOSITS; MODELS", "locations": "Antarctica", "north": -65.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Buizert, Christo; Wettstein, Justin", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -90.0, "title": "Collaborative Research: The Timing and Spatial Expression of the Bipolar Seesaw in Antarctica from Synchronized Ice Cores", "uid": "p0010279", "west": -180.0}, {"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": "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 tetraethers containing 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. ", "east": -38.0, "geometry": "POINT(-41.5 -59.5)", "instruments": null, "is_usap_dc": true, "keywords": "SEA SURFACE TEMPERATURE; USAP-DC; USA/NSF; LABORATORY; AMD; Scotia Sea; AMD/US", "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": "2035580 Aarons, Sarah; 2035637 Tabor, Clay", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 06 Oct 2021 00:00:00 GMT", "description": "The spatial extent of the West Antarctic Ice Sheet during the last interglacial period (129,000 to 116,000 years ago) is currently unknown, yet this information is fundamental to projections of the future stability of the ice sheet in a warming climate. Paleoclimate records and proxy evidence such as dust can inform on past environmental conditions and ice-sheet coverage. This project will combine new, high-sensitivity geochemical measurements of dust from Antarctic ice collected at Allan Hills with existing water isotope records to document climate and environmental changes through the last interglacial period. These changes will then be compared with Earth-system model simulations of dust and water isotopes to determine past conditions and constrain the sensitivity of the West Antarctic Ice Sheet to warming. The project will test the hypothesis that the uncharacteristically volcanic dust composition observed at another peripheral ice core site at Taylor Glacier during the last interglacial period is related to changes in the spatial extent of the West Antarctic Ice Sheet.\r\n\r\nThis project aims to characterize mineral dust transport during the penultimate glacial-interglacial transition. The team will apply high-precision geochemical techniques to the high-volume, high-resolution ice core drilled at the Allan Hills site in combination with Earth system model simulations to: (1) determine if the volcanic dust signature found in interglacial ice from Taylor Glacier is also found at Allan Hills, (2) determine the likely dust source(s) to this site during the last interglacial, and (3) probe the atmospheric and environmental changes during the last interglacial with a diminished West Antarctic Ice Sheet. The team will develop a suite of measurements on previously drilled ice from Allan Hills, including isotopic compositions of Strontium and Neodymium, trace element concentrations, dust-size distribution, and imaging of ice-core dust to confirm the original signal observed and provide a broader spatial reconstruction of dust transport. In tandem, the team will conduct Earth system modeling with prognostic dust and water-isotope capability to test the sensitivity of dust transport under several plausible ice-sheet and freshwater-flux configurations. By comparing dust reconstruction and model simulations, the team aims to elucidate the driving mechanisms behind dust transport during the last interglacial period.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "MICROPARTICLE CONCENTRATION; FIELD SURVEYS; GEOCHEMISTRY; ICE EXTENT; USA/NSF; PALEOCLIMATE RECONSTRUCTIONS; AMD/US; AMD; Allan Hills; ICE CORE RECORDS; USAP-DC", "locations": "Allan Hills", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Aarons, Sarah; Tabor, Clay", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Peripheral East Antarctic ice as a unique recorder of climate variability during the Last Interglacial", "uid": "p0010270", "west": null}, {"awards": "2103032 Schmittner, Andreas", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 09 Sep 2021 00:00:00 GMT", "description": "The Antarctic ice sheet is an important component of Earth\u2019s climate system, as it interacts with the atmosphere, the surrounding Southern Ocean, and the underlaying solid Earth. It is also the largest potential contributor to future sea level rise and a major uncertainty in climate projections. Climate change may trigger instabilities, which may lead to fast and irreversible collapse of parts of the ice sheet. However, very little is known about how interactions between the Antarctic ice sheet and the rest of the climate system affect its behavior, climate, and sea level, partly because most climate models currently do not have fully-interactive ice sheet components. This project investigates Antarctic ice-ocean interactions of the last 20,000 years. A novel numerical climate model will be constructed that includes an interactive Antarctic ice sheet, improving computational infrastructure for research. The model code will be made freely available to the public on a code-sharing site. Paleoclimate data will be synthesized and compared with simulations of the model. The model-data comparison will address three scientific hypotheses regarding past changes in deep ocean circulation, ice sheet, carbon, and sea level. The project will contribute to a better understanding of ice-ocean interactions and past climate variability.\r\n\r\nThis project will test suggestions that ice-ocean interactions have been important for setting deep ocean circulation and carbon storage during the Last Glacial Maximum and subsequent deglaciation. The new model will consist of three existing and well-tested components: (1) an isotope-enabled climate-carbon cycle model of intermediate complexity, (2) a model of the combined Antarctic ice sheet, solid Earth and sea level, and (3) an iceberg model. The coupling will include ocean temperature effects on basal melting of ice shelves, freshwater fluxes from the ice sheet to the ocean, and calving, transport and melting of icebergs. Once constructed and optimized, the model will be applied to simulate the Last Glacial Maximum and subsequent deglaciation. Differences between model versions with full, partial or no coupling will be used to investigate the effects of ice-ocean interactions on the Meridional Overturning Circulation, deep ocean carbon storage and ice sheet fluctuations. Paleoclimate data synthesis will include temperature, carbon and nitrogen isotopes, radiocarbon ages, protactinium-thorium ratios, neodymium isotopes, carbonate ion, dissolved oxygen, relative sea level and terrestrial cosmogenic ages into one multi-proxy database with a consistent updated chronology. The project will support an early-career scientist, one graduate student, undergraduate students, and new and ongoing national and international collaborations. Outreach activities in collaboration with a local science museum will benefit rural communities in Oregon by improving their climate literacy.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "ICE CORE RECORDS; USA/NSF; OCEAN TEMPERATURE; GLACIERS/ICE SHEETS; AMD/US; BIOGEOCHEMICAL CYCLES; MODELS; AMD; United States Of America; OCEAN CURRENTS; ICEBERGS; PALEOCLIMATE RECONSTRUCTIONS", "locations": "United States Of America", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Schmittner, Andreas; Haight, Andrew ; Clark, Peter", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Investigating Antarctic Ice Sheet-Ocean-Carbon Cycle Interactions During the Last Deglaciation", "uid": "p0010256", "west": -180.0}, {"awards": "2114786 Warnock, Jonathan", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 09 Sep 2021 00:00:00 GMT", "description": "The potential for future sea level rise from melting and collapse of Antarctic ice sheets and glaciers is concerning. We can improve our understanding of how water is exchanged between Antarctic ice sheets and the ocean by studying how ice sheets behaved in past climates, especially conditions that were similar to or warmer than those at present. For this project, the research team will document Antarctica\u2019s response across an interval when Earth transitioned from the warm Pliocene into the Pleistocene ice ages by combining marine and land evidence for glacier variations from sites near the Antarctic Peninsula, complimented by detailed work on timescales and fossil evidence for environmental change. An important goal is to test whether Antarctica\u2019s glaciers changed at the same time as glaciers in the Northern Hemisphere as Earth\u0027s most recent Ice Age intensified, or alternatively responded to regional climate forcing in the Southern Hemisphere. Eleven investigators from seven US institutions, as well as Argentine collaborators, will study new sediment cores from the International Ocean Discovery Program, as well as legacy cores from that program and on-land outcrops on James Ross Island. The group embraces a vertically integrated research program that allows high school, undergraduate, graduate, post-docs and faculty to work together on the same projects. This structure leverages the benefits of near-peer mentoring and the development of a robust collaborative research network while allowing all participants to take ownership of different parts of the project. All members of the team are firmly committed to attracting researchers from under-represented groups and will do this through existing channels as well as via co-creating programming that centers the perspectives of diverse students in conversations about sea-level rise and climate change.\r\nThe proposed research seeks to understand phasing between Northern and Southern Hemisphere glacier and climate changes, as a means to understand drivers and teleconnections. The dynamics of past Antarctic glaciation can be studied using the unique isotope geochemical and mineralogic fingerprints from glacial sectors tied to a well-constrained time model for the stratigraphic successions. The proposed work would further refine the stratigraphic context through coupled biostratigraphic and magnetostratigraphic work. The magnitude of iceberg calving and paths of icebergs will be revealed using the flux, geochemical and mineralogic signatures, and 40Ar/39Ar and U-Pb geochronology of ice-rafted detritus. These provenance tracers will establish which sectors of Antarctica\u2019s ice sheets are more vulnerable to collapse, and the timing and pacing of these events will be revealed by their stratigraphic context. Additionally, the team will work with Argentine collaborators to connect the marine and terrestrial records by studying glacier records intercalated with volcanic flows on James Ross Island. These new constraints will be integrated with a state of the art ice-sheet model to link changes in ice dynamics with their underlying causes. Together, these tight stratigraphic constraints, geochemical signatures, and ice-sheet model simulations will provide a means to compare to the global records of climate change, understand their primary drivers, and elucidate the role of the Antarctic ice sheet in a major, global climatic shift from the Pliocene into the Pleistocene.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "MICROFOSSILS; FIELD SURVEYS; AMD/US; Weddell Sea Embayment; USA/NSF; SEA ICE; USAP-DC; PALEOCLIMATE RECONSTRUCTIONS; SEA SURFACE TEMPERATURE; AMD", "locations": "Weddell Sea Embayment", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Warnock, Jonathan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Linking Marine and Terrestrial Sedimentary Evidence for Plio-pleistocene Variability of Weddell Embayment and Antarctic Peninsula Glaciation", "uid": "p0010260", "west": null}, {"awards": "1744993 Higgins, John; 1744832 Severinghaus, Jeffrey; 1745007 Mayewski, Paul; 0838843 Kurbatov, Andrei; 1745006 Brook, Edward", "bounds_geometry": "POLYGON((159.16667 -76.66667,159.19167 -76.66667,159.21667 -76.66667,159.24167 -76.66667,159.26667 -76.66667,159.29167 -76.66667,159.31667 -76.66667,159.34167 -76.66667,159.36667 -76.66667,159.39167 -76.66667,159.41667 -76.66667,159.41667 -76.673336,159.41667 -76.680002,159.41667 -76.686668,159.41667 -76.693334,159.41667 -76.7,159.41667 -76.706666,159.41667 -76.713332,159.41667 -76.719998,159.41667 -76.726664,159.41667 -76.73333,159.39167 -76.73333,159.36667 -76.73333,159.34167 -76.73333,159.31667 -76.73333,159.29167 -76.73333,159.26667 -76.73333,159.24167 -76.73333,159.21667 -76.73333,159.19167 -76.73333,159.16667 -76.73333,159.16667 -76.726664,159.16667 -76.719998,159.16667 -76.713332,159.16667 -76.706666,159.16667 -76.7,159.16667 -76.693334,159.16667 -76.686668,159.16667 -76.680002,159.16667 -76.673336,159.16667 -76.66667))", "dataset_titles": "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 Stable Water Isotopes; I-165-M GPR Field Report 2019-2020", "datasets": [{"dataset_uid": "601696", "doi": "10.15784/601696", "keywords": "Allan Hills; Antarctica; Cryosphere; Ice Core", "people": "Brook, Edward; 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": "609541", "doi": "10.7265/N5NP22DF", "keywords": "Allan Hills; Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Isotope", "people": "Mayewski, Paul A.; Introne, Douglas; Spaulding, Nicole; Kurbatov, Andrei V.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Allan Hills Stable Water Isotopes", "url": "https://www.usap-dc.org/view/dataset/609541"}, {"dataset_uid": "601669", "doi": "10.15784/601669", "keywords": "Allan Hills; Antarctica; Cryosphere; Ground Penetrating Radar; Ice Core; Report", "people": "Brook, Edward; Nesbitt, Ian", "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": "601620", "doi": "10.15784/601620", "keywords": "18O of atmospheric O2; Allan Hills; Allan Hills blue ice; Antarctica; Blue Ice Area; Cryosphere; Delta 15N; Delta 18O; Dole Effect; Dole Effect; Firn Thickness; 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"}], "date_created": "Fri, 27 Aug 2021 00:00:00 GMT", "description": " Between about 2.8-0.9 Ma, Earth\u2019s climate was characterized by 40 kyr cycles, driven or paced by changes in the tilt of Earth\u2019s spin axis. Much is known about the 40k world from studies of deep-sea sediments, but our understanding of climate change during this period and the transition between the 40kyr glacial cycles from 2.8-0.9 Ma and the 100kyr glacial cycles of the last 0.9 Myr is incomplete because we lack records of Antarctic climate and direct records of atmospheric greenhouse gas concentrations. We propose to address these issues by building on our recent studies of \u003e1 Ma ice discovered in shallow ice cores in the Allan Hills Blue Ice Area (BIA), Antarctica. During the 2015-2016 field season we recovered ice from two nearby drill cores that dates to \u003e 2 million years in age using the 40Ar/38Ar ratio of the trapped gases. Our discovery of ice of this antiquity in two cores demonstrates that there is gas-record quality ice from the 40k world in the Allan Hills BIA. To further characterize the composition of Earth\u2019s atmosphere and Antarctic climate during the 40k world we request support for two field seasons to drill new large-volume (4\u201d or 9\u201d diameter) ice cores at sites where we have previously identified \u003e1 Ma ice and nearby sites where ground penetrating radar has identified bedrock features conducive to the preservation of old ice. ", "east": 159.41667, "geometry": "POINT(159.29167 -76.7)", "instruments": null, "is_usap_dc": true, "keywords": "AMD/US; AMD; USAP-DC; SNOW/ICE; Allan Hills; FIELD SURVEYS; USA/NSF; LABORATORY", "locations": "Allan Hills", "north": -76.66667, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Mayewski, Paul A.; Kurbatov, Andrei V.; Brook, Edward J.; Severinghaus, Jeffrey P.; Higgins, John", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.73333, "title": "Collaborative research: Snapshots of Early and Mid-Pleistocene Climate and Atmospheric Composition from the Allan Hills Blue Ice Area ", "uid": "p0010253", "west": 159.16667}, {"awards": "2114839 Passchier, Sandra", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 25 Aug 2021 00:00:00 GMT", "description": "The project targets the long-term variability of the West Antarctic Ice Sheet over several glacial-interglacial cycles in the early Pliocene sedimentary record drilled by the International Ocean Discovery Program (IODP) Expedition 379 in the Amundsen Sea. Data collection includes 1) the sand provenance of ice-rafted debris and shelf diamictites and its sources within the Amundsen Sea and Antarctic Peninsula region; 2) sedimentary structures and sortable silt calculations from particle size records and reconstructions of current intensities and interactions; and 3) the bulk provenance of continental rise sediments compared to existing data from the Amundsen Sea shelf with investigations into downslope currents as pathways for Antarctic Bottom Water formation. The results are analyzed within a cyclostratigraphic framework of reflectance spectroscopy and colorimetry (RSC) and X-ray fluorescence scanner (XRF) data to gain insight into orbital forcing of the high-latitude processes. The early Pliocene Climatic Optimum (PCO) ~4.5-4.1 Ma spans a major warm period recognized in deep-sea stable isotope and sea-surface temperature records. This period also coincides with a global mean sea level highstand of \u003e 20 m requiring contributions in ice mass loss from Antarctica. The following hypotheses will be tested: 1) that the West Antarctic Ice Sheet retreated from the continental shelf break through an increase in sub iceshelf melt and iceberg calving at the onset of the PCO ~4.5 Ma, and 2) that dense shelf water cascaded down through slope channels after ~4.5 Ma as the continental shelf became exposed during glacial terminations. The project will reveal for the first time how the West Antarctic Ice Sheet operated in a warmer climate state prior to the onset of the current \u201cicehouse\u201d period ~3.3 Ma.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; TERRIGENOUS SEDIMENTS; SEDIMENTS; FIELD SURVEYS; AMD/US; Amundsen Sea; USAP-DC; AMD", "locations": "Amundsen Sea", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Passchier, Sandra", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "West Antarctic Ice-sheet Change and Paleoceanography in the Amundsen Sea Across the Pliocene Climatic Optimum", "uid": "p0010252", "west": null}, {"awards": "1947562 van Gestel, Natasja; 1643871 van Gestel, Natasja", "bounds_geometry": "POLYGON((-65 -64.5,-64.8 -64.5,-64.6 -64.5,-64.4 -64.5,-64.2 -64.5,-64 -64.5,-63.8 -64.5,-63.6 -64.5,-63.4 -64.5,-63.2 -64.5,-63 -64.5,-63 -64.55,-63 -64.6,-63 -64.65,-63 -64.7,-63 -64.75,-63 -64.8,-63 -64.85,-63 -64.9,-63 -64.95,-63 -65,-63.2 -65,-63.4 -65,-63.6 -65,-63.8 -65,-64 -65,-64.2 -65,-64.4 -65,-64.6 -65,-64.8 -65,-65 -65,-65 -64.95,-65 -64.9,-65 -64.85,-65 -64.8,-65 -64.75,-65 -64.7,-65 -64.65,-65 -64.6,-65 -64.55,-65 -64.5))", "dataset_titles": null, "datasets": null, "date_created": "Sat, 21 Aug 2021 00:00:00 GMT", "description": "Responses of the carbon balance of terrestrial ecosystems to warming will feed back to the pace of climate change, but the size and direction of this feedback are poorly constrained. Least known are the effects of warming on carbon losses from soil, and clarifying the major microbial controls is an important research frontier. This study uses a series of experiments and observations to investigate microbial, including autotrophic taxa, and plant controls of net ecosystem productivity in response to warming in intact ecosystems. Field warming is achieved using open-top chambers paired with control plots, arrayed along a productivity gradient. Along this gradient incoming and outgoing carbon fluxes will be measured at the ecosystem-level. The goal is to tie warming-induced shifts in net ecosystem carbon balance to warming effects on soil microbes and plants. The field study will be supplemented with lab temperature incubations. Because soil microbes dominate biogeochemical cycles in Antarctica, a major focus of this study is to determine warming responses of bacteria, fungi and archaea. This is achieved using a cutting-edge stable isotope technique, quantitative stable isotope probing (qSIP) developed by the proposing research team, that can identify the taxa that are active and involved in processing new carbon. This technique can identify individual microbial taxa that are actively participating in biogeochemical cycling of nutrients (through combined use of 18O-water and 13C-bicarbonate) and thus can be distinguished from those that are simply present (cold-preserved). The study further assesses photosynthetic uptake of carbon by the vegetation and their sensitivity to warming. Results will advance research in climate change, plant and soil microbial ecology, and ecosystem modeling.", "east": -63.0, "geometry": "POINT(-64 -64.75)", "instruments": null, "is_usap_dc": true, "keywords": "Palmer Station; TERRESTRIAL ECOSYSTEMS; AMD/US; USA/NSF; AMD; USAP-DC; FIELD SURVEYS", "locations": "Palmer Station", "north": -64.5, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Earth Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "van Gestel, Natasja", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -65.0, "title": "Antarctica as a Model System for Responses of Terrestrial Carbon Balance to Warming", "uid": "p0010251", "west": -65.0}, {"awards": "1947453 Hunt, Kathleen; 1927709 Friedlaender, Ari; 1927742 Fleming, Alyson", "bounds_geometry": "POLYGON((150 -60,153 -60,156 -60,159 -60,162 -60,165 -60,168 -60,171 -60,174 -60,177 -60,180 -60,180 -61.5,180 -63,180 -64.5,180 -66,180 -67.5,180 -69,180 -70.5,180 -72,180 -73.5,180 -75,177 -75,174 -75,171 -75,168 -75,165 -75,162 -75,159 -75,156 -75,153 -75,150 -75,150 -73.5,150 -72,150 -70.5,150 -69,150 -67.5,150 -66,150 -64.5,150 -63,150 -61.5,150 -60))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 10 Aug 2021 00:00:00 GMT", "description": "An archive of baleen plates from 800 Antarctic blue and fin whales harvested between 1946 and 1948 was recently rediscovered in the Smithsonian\u2019s National Museum of Natural History. As baleen grows, it incorporates compounds from the whale\u2019s diet and surroundings, recording continuous biological and oceanographic information across multiple years. The baleen record forms an ideal experimental platform for studying bottom-up, top-down and anthropogenic impacts on blue and fin whales. Such insights are likely impossible to obtain through any other means as blue and fin whales now number ~1 and 4% of their pre-whaling abundances. The baleen archive includes years with strong climate and temperature anomalies allowing the influence of climate variability on predators and the ecosystems that support them to be examined. Additionally, the impact of whaling on whale stress levels will be investigated by comparing years of intensive whaling with the non-whaling years of WWII, both of which are captured in the time series. We will use 1) bulk stable isotopes to examine the trophic dynamics of Antarctic blue and fin whales, 2) compound-specific stable isotope analysis (CSIA-AA) to characterize the biogeochemistry of the base of the Antarctic food web and 3) hormone analyses to examine the population biology of these species. These investigations will fill major gaps in our understanding of the largest krill predators, their response to disturbance and environmental change, and the impact that commercial whaling has had on the structure and function of the Antarctic marine ecosystem.", "east": 180.0, "geometry": "POINT(165 -67.5)", "instruments": null, "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; PELAGIC; MAMMALS; LABORATORY; AMD; AMD/US; Southern Ocean; USAP-DC; USA/NSF", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Fleming, Alyson; Friedlaender, Ari; McCarthy, Matthew; Hunt, Kathleen", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -75.0, "title": "Collaborative Research: A New Baseline for Antarctic Blue and Fin Whales", "uid": "p0010240", "west": 150.0}, {"awards": "1745080 Gillikin, David; 1745064 Perez-Huerta, Alberto; 1745057 Walker, Sally", "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": "Analysis of striae groups and interstrial increments from Adamussium colbecki valves from Explorers Cove and Bay of Sails; Annual growth of Adamussium colbecki from Explorers Cove and Bay of Sails; Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores", "datasets": [{"dataset_uid": "601469", "doi": "10.15784/601469", "keywords": "Adamussium colbecki; Antarctica; Cryosphere; McMurdo", "people": "Walker, Sally; Cronin, Kelly", "repository": "USAP-DC", "science_program": null, "title": "Analysis of striae groups and interstrial increments from Adamussium colbecki valves from Explorers Cove and Bay of Sails", "url": "https://www.usap-dc.org/view/dataset/601469"}, {"dataset_uid": "600077", "doi": "10.15784/600077", "keywords": "Antarctica; Biology; Biosphere; Glaciers/Ice Sheet; McMurdo Sound; Oceans; Sample/Collection Description", "people": "Walker, Sally", "repository": "USAP-DC", "science_program": null, "title": "Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores", "url": "https://www.usap-dc.org/view/dataset/600077"}, {"dataset_uid": "601468", "doi": "10.15784/601468", "keywords": "Adamussium colbecki; Antarctica; Cryosphere; growth; McMurdo Sound; Shell fish", "people": "Walker, Sally; Cronin, Kelly", "repository": "USAP-DC", "science_program": null, "title": "Annual growth of Adamussium colbecki from Explorers Cove and Bay of Sails", "url": "https://www.usap-dc.org/view/dataset/601468"}], "date_created": "Fri, 06 Aug 2021 00:00:00 GMT", "description": "The goal of this project is to discover whether the Antarctic scallop, Adamussium colbecki, provides a guide to sea-ice conditions in nearshore Antarctica today and in the past. Scallops may grow slower and live longer in habitats where sea ice persists for many years, limited by food, compared to habitats where sea ice melts out annually. Also, the chemicals retained in the shell during growth may provide crucial habitat information related to not only changing sea-ice conditions but also the type of food, whether it is recycled from the seafloor or produced by algae blooming when sea ice has melted. Unlocking the ecological imprint captured within the shell of the Antarctic Scallop will increase our understanding of changing sea-ice conditions in Antarctica. Further, because the Antarctic scallop had relatives living at the time when the Antarctic ice sheet first appeared, the scallop shell record may contain information on the stability of the ice sheet and the history of Antarctic shallow seas. Funding will also be integral for training a new generation of geoscientists in fossil and chemical forensics related to shallow sea habitats in Antarctica.\r\n\r\nScallops are worldwide in distribution, are integral for structuring marine communities have an extensive fossil record dating to the late Devonian, and are increasingly recognized as important paleoenvironmental proxies because they are generally well preserved in the sediment and rock record. The primary goal of this project is to assess the differences in growth, lifespan, and chemistry (stable isotopes, trace elements) archived in the shell of the Antarctic scallop that may be indicative of two ice states: persistent (multiannual) sea ice at Explorers Cove (EC) and annual sea ice (that melts out every year) at Bay of Sails (BOS), western McMurdo Sound, Antarctica. This project will investigate growth and lifespan proxies (physical and geochemical) and will use high-resolution records of stable oxygen isotopes to determine if a melt-water signal is archived in A. colbecki shells and whether that signal captures the differing ice behavior at two sites (EC versus BOS). Stable isotopes of carbon and nitrogen in association with trace elements will be used to examine subannual productivity spikes indicative of phytoplankton blooms, which are predicted to be more pronounced during open ocean conditions. Small growth increments in the outer calcite layer will be assessed to determine if they represent fortnightly growth, if so, they could provide a high-resolution proxy for monthly environmental processes. Unlocking the environmental archive preserved in A. colbecki shells may prove to be an important proxy for understanding changing sea-ice conditions in Antarctica\u0027s past. Funding will support a Ph.D. student and undergraduates from multiple institutions working on independent research projects. Web content focused on Antarctic marine communities will be designed for museum outreach, reaching thousands of middle-school children each year.\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "PALEOCLIMATE RECONSTRUCTIONS; AMD; Dry Valleys; USAP-DC; AMD/US; LABORATORY; USA/NSF", "locations": "Dry Valleys", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Walker, Sally; Gillikin, David; Perez-Huerta, Alberto; Andrus, Fred", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative research: The Antarctic Scallop as Key to Paleoenvironments and Sea Ice Conditions: Understanding the Modern to Predict the Past", "uid": "p0010238", "west": -180.0}, {"awards": "1744871 Robinson, Rebecca", "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": "Dissolved nutrients, cell counts, and nitrogen isotope measurements from Chaetoceros socialis culture experiments; ODP Site 1098 deglacial diatom assemblage; Sediment chemistry of ODP Site 1098", "datasets": [{"dataset_uid": "601720", "doi": "10.15784/601720", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere", "people": "Dove, Isabel", "repository": "USAP-DC", "science_program": null, "title": "Sediment chemistry of ODP Site 1098", "url": "https://www.usap-dc.org/view/dataset/601720"}, {"dataset_uid": "601727", "doi": "10.15784/601727", "keywords": "Antarctica; Cryosphere", "people": "Dove, Isabel", "repository": "USAP-DC", "science_program": null, "title": "Dissolved nutrients, cell counts, and nitrogen isotope measurements from Chaetoceros socialis culture experiments", "url": "https://www.usap-dc.org/view/dataset/601727"}, {"dataset_uid": "601723", "doi": "10.15784/601723", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Glaciers/Ice Sheet", "people": "Dove, Isabel", "repository": "USAP-DC", "science_program": null, "title": "ODP Site 1098 deglacial diatom assemblage", "url": "https://www.usap-dc.org/view/dataset/601723"}], "date_created": "Wed, 28 Jul 2021 00:00:00 GMT", "description": "The chemical composition of diatom fossils in the Southern Ocean provides information about the environmental history of Antarctica, including sea ice extent, biological production, and ocean nutrient distribution. The sea ice zone is an important habitat for a group of diatoms, largely from the genus Chaetoceros, that have a unique life cycle stage under environmental stress, when they produce a structure called a resting spore. Resting spores are meant to reseed the surface ocean when conditions are more favorable. The production of these heavy resting spores tends to remove significant amounts of carbon and silicon, essential nutrients, out of the surface ocean. As a result, this group has the potential to remove carbon from the surface ocean and can impact the sedimentary record scientists use to reconstruct environmental change. \r\n\r\nThis project explores the role of resting spores and nutrients in the sedimentary record using the nitrogen isotopic signature of these fossils and how those measurements are used to estimate carbon cycle changes. Measurements of nitrogen stable isotopes of nitrate, biomass, and diatom-bound nitrogen and silicon-to-nitrogen ratios of individual species grown in the laboratory are used to quantify how resting spores record nutrient drawdown in the water column and to what degree their signature is biased toward low nutrient conditions. Laboratory incubations were conducted with surface sediment containing Chaetoceros spp.. The emergence of vegetative cells and subsequent formation of resting spores is manipulated with the addition of nutrients, primarily nitrate. The resulting samples, both of vegetative cells and resting spores were measured for diatom-bound d15N. Resting spore d15N values are consistently lower than the vegetative d15N \r\n from the same incubations. The incubation results will be used to quantify nutrient drawdown in sea ice environments during two contrasting intervals in earth history, the last ice age and the warm Pliocene. The project provided training and research opportunities for undergraduate and graduate students. Research efforts in Antarctic earth sciences are disseminated through an interactive display at the home institution and during university sponsored events.\r\n\r\nThis work addresses uncertainties in how Chaetoceros resting spores record surface nutrient conditions in their nitrogen stable isotopic composition, the relative impact of their specific signal with respect to the full sedimentary assemblage, and their potential to bias or enhance environmental reconstructions in the sea ice zone. \r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; Antarctica; ISOTOPES; MARINE SEDIMENTS; LABORATORY; USA/NSF; AMD/US; NITROGEN; AMD", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Robinson, Rebecca", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "uid": "p0010234", "west": -180.0}, {"awards": "1445205 Putkonen, Jaakko", "bounds_geometry": "POLYGON((157.6 -83.2,157.62 -83.2,157.64 -83.2,157.66 -83.2,157.68 -83.2,157.7 -83.2,157.72 -83.2,157.74 -83.2,157.76 -83.2,157.78 -83.2,157.8 -83.2,157.8 -83.21,157.8 -83.22,157.8 -83.23,157.8 -83.24,157.8 -83.25,157.8 -83.26,157.8 -83.27,157.8 -83.28,157.8 -83.29,157.8 -83.3,157.78 -83.3,157.76 -83.3,157.74 -83.3,157.72 -83.3,157.7 -83.3,157.68 -83.3,157.66 -83.3,157.64 -83.3,157.62 -83.3,157.6 -83.3,157.6 -83.29,157.6 -83.28,157.6 -83.27,157.6 -83.26,157.6 -83.25,157.6 -83.24,157.6 -83.23,157.6 -83.22,157.6 -83.21,157.6 -83.2))", "dataset_titles": "Cosmogenic-Nuclide data at ICE-D; Old Ice, Ong Valley, Transantarctic Mountains", "datasets": [{"dataset_uid": "200295", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic-Nuclide data at ICE-D", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "601665", "doi": "10.15784/601665", "keywords": "Antarctica; Buried Ice; Cosmogenic Isotopes; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Old Ice; Ong Valley", "people": "Bergelin, Marie; Putkonen, Jaakko", "repository": "USAP-DC", "science_program": null, "title": "Old Ice, Ong Valley, Transantarctic Mountains", "url": "https://www.usap-dc.org/view/dataset/601665"}], "date_created": "Fri, 16 Jul 2021 00:00:00 GMT", "description": "Finding the oldest ice on Earth can tell us about the climate and life forms in the distant past\r\n\r\nRecently we discovered a mile wide and hundreds of feet thick ice body in Antarctica that is buried under just a few feet of dirt. Thus far our analyses of the dirt suggest that the ice is over million years old. Generally, glacial ice contains tiny bubbles and dirt that was deposited and locked in the ice by the ancient snowfall and today still holds small samples of the atmospheric gases and everything else that was carried by the winds in the past. Such samples may include the amount of greenhouse gases, plant pollen, microbes, and mineral dust. Therefore the glaciers are like archives where we can access and study the Earth\u2019s history with samples that are unavailable anywhere else. Ice survives poorly on Earth\u2019s surface and therefore currently only few ice samples are known that are approximately million years old. Our site has a high potential to harbor perhaps the oldest ice on Earth. However, first we need to sample and date the ice. Our research will also help us understand how these pockets of buried ice can survive such unusually long periods of time. Such understanding will help us study the landforms and history of not only Antarctica but also the Mars where similar dirt covered glaciers are found today.\r\n\r\nWe propose to collect regolith samples through the approximately 1 m thick cover and to core the buried ice in Ong Valley down to 10 m depth to determine the cosmogenic nuclide concentrations both in the regolith and in the embedded mineral matter suspended in the ice. The systematics of the target cosmogenic nuclides (10Be, 26Al, and 21Ne) such as half-lives, isotope production rates, production pathways, and related attenuation lengths allow us to uniquely determine the age of the ice and the rate the ice is sublimating. Our existing samples and analyses reveal accumulation of mineral matter at the base of surficial debris layer and the surface erosion of this debris by eolian processes. The intellectual merit of the proposed activity: Our main objective is to unequivocally determine the age and sublimation rate of two buried massive ice bodies in time scale of thousands to millions of years. The slow sublimation is a fundamentally Antarctic process, and may have altered most of the currently ice-free areas throughout the continent. Similar large, debris covered ice bodies have been recently discovered in Mars as well. Our results may transform the understanding of the longevity of the buried ice bodies and potentially reveal the oldest ice ever found in the interior of the Antarctica. If proven old and slowly sublimating, this buried ice can potentially yield direct information about the atmospheric chemistry, ancient life forms, and geology of greater antiquity than the currently available and sampled ice bodies. The broader impacts resulting from the proposed activity: The results will be relevant to researchers in glaciology, paleoclimatology, planetary geology, and biology. Several students will participate in the project and do field work in Antarctica, work in lab, attend meetings, attend outreach activities, and produce videos. A graduate student will prepare his/her thesis on a topic closely related to the objectives of the proposed research. The results of the research will be published in scientific meetings and publications.\r\n", "east": 157.8, "geometry": "POINT(157.7 -83.25)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; USA/NSF; FIELD SURVEYS; Transantarctic Mountains; AMD/US; GLACIERS/ICE SHEETS; AMD", "locations": "Transantarctic Mountains", "north": -83.2, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "putkonen, jaakko; Balco, Gregory; Morgan, Daniel", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "ICE-D", "repositories": "ICE-D; USAP-DC", "science_programs": null, "south": -83.3, "title": "Collaborative Research: Long Term Sublimation/Preservation of Two Separate, Buried Glacier Ice Masses, Ong Valley, Southern Transantarctic Mountains", "uid": "p0010231", "west": 157.6}, {"awards": "2000992 Romans, Brian", "bounds_geometry": "POINT(-172.873074 -74.274008)", "dataset_titles": null, "datasets": null, "date_created": "Tue, 06 Jul 2021 00:00:00 GMT", "description": "Geological records from the Antarctic Ice Sheet (AIS) margin demonstrate that the ice sheet oscillated in response to orbital variations in insolation (i.e., ~400, 100, 41, and 20 kyr), and it appears to be more sensitive to specific frequencies that regulate mean annual insolation (i.e., 41-kyr obliquity), particularly when the ice sheet extends into marine environments and is impacted by ocean circulation. However, the relationship between orbital forcing and the production of Antarctic Bottom Water (AABW) is unconstrained. Thus, a knowledge gap exists in understanding how changing insolation impacts ice marginal and Southern Ocean conditions that directly influence ventilation of the global ocean. We hypothesize that insolation-driven changes directly affected the production and export of AABW to the Southern Ocean from the Pliocene through the Pleistocene. For example, obliquity amplification during the warmer Pliocene may have led to enhanced production and export of dense waters from the shelf due to reduced AIS extent, which, in turn, led to greater AABW outflow. To determine the relationship of AABW production to orbital regime, we plan to reconstruct both from a single, continuous record from the levee of Hillary Canyon, a major conduit of AABW outflow, on the Ross Sea continental rise. \r\n\r\nTo test our hypothesis, we will analyze sediment from IODP Site U1524 (recovered in 2018 during International Ocean Discovery Program Expedition 374) and focus on three data sets. (1) We will use the occurrence, frequency, and character of mm-scale turbidite beds as a proxy of dense-shelf-water cascading outflow and AABW production. We will estimate the down-slope flux via numerical modeling of turbidity current properties using morphology, grain size, and bed thickness as input parameters. (2) We will use grain-size data, physical properties, XRF core scanning, CT imaging, and hyperspectral imaging to guide lithofacies analysis to infer processes occurring during glacial, deglacial, and interglacial periods. Statistical techniques and optimization methods will be applied to test for astronomical forcing of sedimentary packages in order to provide a cyclostratigraphic framework and interpret the orbital-forcing regime. (3) We will use bulk sedimentary carbon and nitrogen abundance and isotope data to determine how relative contributions of terrigenous and marine organic matter change in response to orbital forcing. We will integrate these data with sedimentological records to deconvolve organic matter production from its deposition or remobilization due to AABW outflow as a function of the oscillating extent of the AIS. These data sets will be integrated into a unified chronostratigraphy to determine the relationship between AABW outflow and orbital-forcing scenarios under the varying climate regimes of the Plio-Pleistocene.\r\n", "east": -172.873074, "geometry": "POINT(-172.873074 -74.274008)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; LABORATORY; AMD/US; AMD; USA/NSF; SEDIMENTS; Ross Sea", "locations": "Ross Sea", "north": -74.274008, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Romans, Brian; Patterson, Molly; Ash, Jeanine; Kulhanek, Denise; Ash, Jeannie", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -74.274008, "title": "COLLABORATIVE RESEARCH: Orbital-scale Variability of the West Antarctic Ice Sheet and the Formation of Bottom Water in the Ross Sea during the Pliocene-Pleistocene", "uid": "p0010227", "west": -172.873074}, {"awards": "1341475 Smith, Nathan; 2001033 Makovicky, Peter; 1341645 Makovicky, Peter; 1341304 Sidor, Christian; 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; Cryosphere; Fremouw Formation; Lystrosaurus; Permo-Triassic Extinction; Prolacerta; Sample Location; Thrinaxofon; Triassic", "people": "Makovicky, Peter", "repository": "USAP-DC", "science_program": null, "title": "Lower Triassic Antarctic vertebrate fossils at Field Museum, Chicago, IL", "url": "https://www.usap-dc.org/view/dataset/601511"}], "date_created": "Tue, 29 Jun 2021 00:00:00 GMT", "description": "This project will advance our understanding of Antarctic life during the Permian and Triassic. We will apply an interdisciplinary approach to address relationships between environmental change, faunal composition, and biogeographic patterns in the context of the high-latitude strata preserved in the Buckley and Fremouw formations in the Shackleton Glacier region. We will use multiple types of data to assess paleoenvironment, including: 1) paleosol morphology; 2) paleosol geochemistry; 3) pedogenic organic matter; and 4) fossil wood chronology and stable isotopes. The Fremouw Formation of Antarctica preserves the highest paleolatitude tetrapod fauna of the entire Triassic (~70\u00b0 S) and thus has the potential to shed important light on the evolution of polar life during the early Mesozoic. We will collect new fossils from known localities to understand the relationship between Antarctic and southern African tetrapod faunas. Furthermore, we will refine the stratigraphic, sedimentological, and geochronological framework for these Mesozoic faunas, which will include using U/Pb detrital zircon dating to provide the first dates for these vertebrate assemblages. In the lab, we will examine the biology of Triassic vertebrates from Antarctica by comparing their bone and tusk histology to conspecifics from lower paleolatitudes. In addition, we will test Bergmann\u2019s Rule with six species (viz. Lystrosaurus curvatus, L. maccaigi, L. murrayi, Prolacerta broomi, Procolophon trigoniceps, and Thrinaxodon liorhinus). The Early Triassic presents a unique opportunity to perform such investigations as there is no other geologic interval in which species occurring in Antarctica can be compared to conspecifics across a range of paleolatitudes.", "east": -160.0, "geometry": "POINT(-177.5 -85.5)", "instruments": null, "is_usap_dc": true, "keywords": "REPTILES; FIELD SURVEYS; USA/NSF; AMD/US; PALEOCLIMATE RECONSTRUCTIONS; Triassic; USAP-DC; TERRESTRIAL ECOSYSTEMS; MACROFOSSILS; Shackleton Glacier; fossils; 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": "1644159 Jacobs, Stanley", "bounds_geometry": "POLYGON((-180 -72.5,-177 -72.5,-174 -72.5,-171 -72.5,-168 -72.5,-165 -72.5,-162 -72.5,-159 -72.5,-156 -72.5,-153 -72.5,-150 -72.5,-150 -73.15,-150 -73.8,-150 -74.45,-150 -75.1,-150 -75.75,-150 -76.4,-150 -77.05,-150 -77.7,-150 -78.35,-150 -79,-153 -79,-156 -79,-159 -79,-162 -79,-165 -79,-168 -79,-171 -79,-174 -79,-177 -79,180 -79,178.2 -79,176.4 -79,174.6 -79,172.8 -79,171 -79,169.2 -79,167.4 -79,165.6 -79,163.8 -79,162 -79,162 -78.35,162 -77.7,162 -77.05,162 -76.4,162 -75.75,162 -75.1,162 -74.45,162 -73.8,162 -73.15,162 -72.5,163.8 -72.5,165.6 -72.5,167.4 -72.5,169.2 -72.5,171 -72.5,172.8 -72.5,174.6 -72.5,176.4 -72.5,178.2 -72.5,-180 -72.5))", "dataset_titles": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020; Ross Island area salinity and temperature records 1956 to 2020", "datasets": [{"dataset_uid": "601611", "doi": "10.15784/601611", "keywords": "Amundsen Sea; Antarctica; Chemistry:Water; Cryosphere; 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"}, {"dataset_uid": "601458", "doi": "10.15784/601458", "keywords": "Antarctica; Cryosphere; CTD; Oceans; Physical Oceanography; Ross Island; Ross Sea; Salinity; Temperature", "people": "Giulivi, Claudia; Jacobs, Stanley", "repository": "USAP-DC", "science_program": null, "title": "Ross Island area salinity and temperature records 1956 to 2020", "url": "https://www.usap-dc.org/view/dataset/601458"}], "date_created": "Fri, 25 Jun 2021 00:00:00 GMT", "description": "This project extended and combined historical and recent ocean data sets to investigate ice-ocean-interactions along the Pacific continental margin of the West Antarctic Ice Sheet. The synthesis focused on the strikingly different environments on and near the cold Ross Sea and warm Amundsen Sea continental shelves, where available measurements reach back to 1911 and 1994, respectively. On the more extensively covered Ross Sea continental shelf, multiple reoccupations of ocean stations and transects since the 1950s were used to extend our knowledge of ocean thermohaline change and variability. The more rugged Amundsen Sea continental shelf contains the earth\u0027s fastest melting ice shelves, which Holland et al (2019) show can be linked to decadal-scale variability in the tropical Pacific, and Jacobs et al. (2021) document as being the primary influence on freshening downstream in the Ross Sea. Recent and potential future rates of sea level rise are the primary broad-scale impacts revealed by the observations of ice and ocean changes in these study areas. More regionally, freshening also influences the properties of slope front and coastal currents, and abyssal water mass formation. The overriding question in such work is whether their contributions to global and regional sea levels will continue to increase ~linearly, perhaps allowing greenhouse gas reductions to head off the worst consequences, or accelerate and contribute to major social and economic upheavals. The compiled ocean station profile data has been derived from measurements made from 16 ships operated by 6 countries, from 5 projects using holes through fast and glacier ice, and from 3 studies using drifting floats. We are grateful to the many individuals who have acquired, processed and provided the data, along with their supporting agencies, and welcome corrections and updates to this archive.\n\n", "east": -150.0, "geometry": "POINT(-174 -75.75)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; USA/NSF; COMPUTERS; AMD/US; Ross Sea; SHIPS; USAP-DC; SALINITY/DENSITY; OCEAN TEMPERATURE", "locations": "Ross Sea", "north": -72.5, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jacobs, Stanley", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS; OTHER \u003e MODELS \u003e COMPUTERS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "West Antarctic Ice Shelf- Ocean Interactions ", "uid": "p0010208", "west": 162.0}, {"awards": "1643494 Saal, Alberto", "bounds_geometry": "POLYGON((-68.074 -57.345,-66.6033 -57.345,-65.1326 -57.345,-63.6619 -57.345,-62.1912 -57.345,-60.7205 -57.345,-59.2498 -57.345,-57.7791 -57.345,-56.3084 -57.345,-54.8377 -57.345,-53.367 -57.345,-53.367 -58.12517,-53.367 -58.90534,-53.367 -59.68551,-53.367 -60.46568,-53.367 -61.24585,-53.367 -62.02602,-53.367 -62.80619,-53.367 -63.58636,-53.367 -64.36653,-53.367 -65.1467,-54.8377 -65.1467,-56.3084 -65.1467,-57.7791 -65.1467,-59.2498 -65.1467,-60.7205 -65.1467,-62.1912 -65.1467,-63.6619 -65.1467,-65.1326 -65.1467,-66.6033 -65.1467,-68.074 -65.1467,-68.074 -64.36653,-68.074 -63.58636,-68.074 -62.80619,-68.074 -62.02602,-68.074 -61.24585,-68.074 -60.46568,-68.074 -59.68551,-68.074 -58.90534,-68.074 -58.12517,-68.074 -57.345))", "dataset_titles": "Major, trace elements contents and radiogenic isotopes of erupted lavas Antarctic Peninsula and Phoenix Ridge", "datasets": [{"dataset_uid": "601519", "doi": "10.15784/601519", "keywords": "Antarctica; Antarctic Peninsula; Chemical Composition; Chemistry:Rock; Cryosphere; Geochemistry; isotope data; Trace Elements", "people": "Saal, Alberto", "repository": "USAP-DC", "science_program": null, "title": "Major, trace elements contents and radiogenic isotopes of erupted lavas Antarctic Peninsula and Phoenix Ridge", "url": "https://www.usap-dc.org/view/dataset/601519"}], "date_created": "Tue, 22 Jun 2021 00:00:00 GMT", "description": "The focus of our research is to examine the regional geochemical variations of well-characterized Pliocene-recent basalt samples along a transect from the Phoenix-Antarctic ridge to James Ross Island (through the South Shetland Islands, Bransfield Strait and the Antarctic Peninsula). The goal is to understand 1) the processes responsible for the generation of chemically diverse basalts in close spatial and temporal proximity within the Antarctic Peninsula and 2) the nature (lithology, composition and temperature) of the heterogeneous mantle source beneath the region.", "east": -53.367, "geometry": "POINT(-60.7205 -61.24585)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; AMD/US; USA/NSF; USAP-DC; TRACE ELEMENTS; MAJOR ELEMENTS; LABORATORY; ROCKS/MINERALS/CRYSTALS; Magmatic Volatiles; AMD", "locations": "Antarctic Peninsula", "north": -57.345, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Saal, Alberto", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.1467, "title": "Magmatic Volatiles, Unraveling the Reservoirs and Processes of the Volcanism in the Antarctic Peninsula", "uid": "p0010196", "west": -68.074}, {"awards": "2048351 Lindow, Julia", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 26 Feb 2021 00:00:00 GMT", "description": "Measurements of in-situ produced cosmogenic nuclides in Antarctic surficial rock samples provide unique time scales for glacial and landscape evolution processes. However, due to analytical challenges, pyroxene-bearing and widely distributed lithologies like the Ferrar dolerite of the Transantarctic Mountains, are underutilized. This proposal aims to changes this and to improve the cosmogenic nuclide methodologies for stable isotopes (21Ne and 3He) and radioactive nuclides (10Be) in pyroxenes. Proposed methodological improvements will be directly applicable to erosion rates and deposition ages of important glacial deposits, such as the controversial Sirius Group tills, and also to younger glacial features. Bennett Platform is the focus of this study because it is one of the southern-most Sirius Group outcrops along the Transantarctic Mountains, where cosmogenic ages are sparse.\r\n\r\nPreliminary measurements demonstrate large discrepancies between 3He and 21Ne age determinations in Sirius Group pyroxenes. One possible explanation is composition dependence of the 21Ne production rates. Coupled measurements of 3He, 21Ne, and 10Be in well-characterized pyroxene mineral separates from Ferrar dolerite will be used to better constrain the production rates, major element and trace element dependencies, the assumptions of the method, and ultimately advance the application of cosmogenic nuclides to mafic Antarctic lithologies.\r\n\r\nThe main goals of this study are to improve measurement protocols for 10Be in pyroxene, and the determination of the composition dependence of 21Ne production rates by measuring mineral compositions (by electron microprobe), and nuclide concentrations in mineral pairs from young lava flows. Further aims are the validation of the nucleogenic contributions and the effects of helium diffusive loss through measurements of 3He/21Ne production ratios, combined with measurements of shielded samples of the Ferrar dolerite. Combined measurements of 3He, 21Ne and 10Be in pyroxenes have rarely been published for individual samples in Antarctica. The new and unique measurements of this study will advance the applicability of in-situ produced cosmogenic nuclides to both young and ancient Antarctic surfaces. The study will be performed using existing samples: no field work is requested.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; AMD; FIELD INVESTIGATION; LABORATORY; Transantarctic Mountains; USAP-DC; GLACIAL LANDFORMS; AMD/US", "locations": "Transantarctic Mountains", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Lindow, Julia; Kurz, Mark D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "New Cosmogenic 21Ne and 10Be Measurements in the Transantarctic Mountains", "uid": "p0010163", "west": null}, {"awards": "1443448 Schaefer, Joerg; 1443144 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": "Simulations of 10Be over Antarctica; South Pole ice Core 10Be CE", "datasets": [{"dataset_uid": "601431", "doi": "10.15784/601431", "keywords": "Antarctica; Cryosphere; 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; Cryosphere; 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 acquired 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 provide a record of changes in solar activity. To ain interpretation of the South Pole 10Be record, 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 is used to quantify the impact of climate noise on the 10Be signal.", "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": "0838757 Balco, Gregory; 0838968 Putkonen, Jaakko", "bounds_geometry": "POLYGON((-158.00085 -83.2093,-157.945063 -83.2093,-157.889276 -83.2093,-157.833489 -83.2093,-157.777702 -83.2093,-157.721915 -83.2093,-157.666128 -83.2093,-157.610341 -83.2093,-157.554554 -83.2093,-157.498767 -83.2093,-157.44298 -83.2093,-157.44298 -83.50197,-157.44298 -83.79464,-157.44298 -84.08731,-157.44298 -84.37998,-157.44298 -84.67265,-157.44298 -84.96532,-157.44298 -85.25799,-157.44298 -85.55066,-157.44298 -85.84333,-157.44298 -86.136,-157.498767 -86.136,-157.554554 -86.136,-157.610341 -86.136,-157.666128 -86.136,-157.721915 -86.136,-157.777702 -86.136,-157.833489 -86.136,-157.889276 -86.136,-157.945063 -86.136,-158.00085 -86.136,-158.00085 -85.84333,-158.00085 -85.55066,-158.00085 -85.25799,-158.00085 -84.96532,-158.00085 -84.67265,-158.00085 -84.37998,-158.00085 -84.08731,-158.00085 -83.79464,-158.00085 -83.50197,-158.00085 -83.2093))", "dataset_titles": "Interface to observational data and geologic age information calculated therefrom; Web page with links to files containing cosmogenic noble gas concentrations and related analytical data", "datasets": [{"dataset_uid": "200197", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Interface to observational data and geologic age information calculated therefrom", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200198", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Web page with links to files containing cosmogenic noble gas concentrations and related analytical data", "url": "http://noblegas.berkeley.edu/~balcs/ongvalley/"}], "date_created": "Sun, 20 Dec 2020 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The proposed project will investigate the coldest and driest parts of the Transantarctic Mountains (Ong Valley at Nimrod Glacier and Moraine Canyon at Amundsen Glacier) where the lack of running water and biological activity in the modern environment is thought to have preserved the landscape, essentially unchanged, for millions of years. Contrary to this common belief, it is hypothesized that the landscape does evolve, perhaps as fast as many surfaces in the Dry Valleys area where both loose soil and bedrock surfaces have been degrading at a rate of about 1-2 m/Myrs for the past several million years. The research team will rely on analysis of the both stable and radioactive cosmogenic isotopes that accumulate in near surface soil and bedrock. Collectively these measurements allow comparison of the long term landscape evolution to current processes and environmental drivers such as wind speed. The results of this work will improve understanding of the evolution of the Earth\u0027s surface and directly aid in evaluating imagery of Martian geomorphology. Continued reliance on students provides a broader impact to this proposed research and firmly grounds this effort in its educational mission.", "east": -157.44298, "geometry": "POINT(-157.721915 -84.67265)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; NOT APPLICABLE; Antarctica", "locations": "Antarctica", "north": -83.2093, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Balco, Gregory; Putkonen, Jaakko; Morgan, Daniel", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "ICE-D", "repositories": "ICE-D; PI website", "science_programs": null, "south": -86.136, "title": "Collaborative Research: Systematic Analysis of Landscape Evolution and Surface Ages in Transantarctic Mountains", "uid": "p0010152", "west": -158.00085}, {"awards": "1842115 Jahn, Alexandra; 1842176 Bizimis, Michael; 1842059 Huber, Matthew; 1842049 Kim, Sora", "bounds_geometry": "POLYGON((-56.693516 -64.209061,-56.6823452 -64.209061,-56.6711744 -64.209061,-56.6600036 -64.209061,-56.6488328 -64.209061,-56.637662 -64.209061,-56.6264912 -64.209061,-56.6153204 -64.209061,-56.6041496 -64.209061,-56.5929788 -64.209061,-56.581808 -64.209061,-56.581808 -64.2143344,-56.581808 -64.2196078,-56.581808 -64.2248812,-56.581808 -64.2301546,-56.581808 -64.235428,-56.581808 -64.2407014,-56.581808 -64.2459748,-56.581808 -64.2512482,-56.581808 -64.2565216,-56.581808 -64.261795,-56.5929788 -64.261795,-56.6041496 -64.261795,-56.6153204 -64.261795,-56.6264912 -64.261795,-56.637662 -64.261795,-56.6488328 -64.261795,-56.6600036 -64.261795,-56.6711744 -64.261795,-56.6823452 -64.261795,-56.693516 -64.261795,-56.693516 -64.2565216,-56.693516 -64.2512482,-56.693516 -64.2459748,-56.693516 -64.2407014,-56.693516 -64.235428,-56.693516 -64.2301546,-56.693516 -64.2248812,-56.693516 -64.2196078,-56.693516 -64.2143344,-56.693516 -64.209061))", "dataset_titles": "Data from: Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota", "datasets": [{"dataset_uid": "200183", "doi": "https://doi.org/10.6071/M34T1Z", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Data from: Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota", "url": "https://datadryad.org/stash/dataset/doi:10.6071/M34T1Z"}], "date_created": "Tue, 15 Dec 2020 00:00:00 GMT", "description": "The Earth\u0027s climate has changed through time and during the Eocene Epoch (56 to 34 million years ago) there was a transition from \u0027greenhouse\u0027 to \u0027icehouse\u0027 conditions. During the Eocene, a shift to cooler temperatures at high latitudes resulted in the inception of polar glaciation. This in turn affected the environment for living organisms. This project looks to uncover the interaction between biological, oceanographic, and climate systems for the Eocene in Antarctica using chemical analysis of fossil shark teeth collected during past expeditions. The combination of paleontological and geochemical analyses will provide insight to the past ecology and ocean conditions; climate models will be applied to test the role of tectonics, greenhouse gas concentration and ocean circulation on environmental change during this time period. The study contributes to understanding the interaction of increased atmospheric carbon dioxide and ocean circulation. This project also seeks to improve diversity, equity, and inclusion within the geosciences workforce with efforts targeted to undergraduate, graduate, postdoctoral, and early career faculty.\u003cbr/\u003e\u003cbr/\u003eThe research goal is to elucidate the processes leading from the Eocene greenhouse to Oligocene icehouse conditions. Previous explanations for this climate shift centers on Antarctica, where tectonic configurations influenced oceanic gateways, ocean circulation reduced heat transport, and/or greenhouse gas declines prompted glaciation. The team will reconstruct watermass, current, and climate fluctuations proximal to the Antarctic Peninsula using geochemical indicators (oxygen and neodymium isotope composition) from fossil shark teeth collected from Seymour Island. The approach builds on previous shark paleontological studies, incorporates geochemical analyses for environmental reconstruction (i.e., temperature gradients and ocean circulation), and tests hypotheses on Earth System dynamics using novel global climate model simulations with geochemical tracers. This project will advance global climate modeling capabilities with experiments that consider Eocene tectonic configuration within isotope-enabled climate model simulations. A comparison of geochemical results from Eocene climate simulations and empirical records of shark teeth will reveal processes and mechanisms central to the Eocene Antarctic climatic shift.\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": -56.581808, "geometry": "POINT(-56.637662 -64.235428)", "instruments": null, "is_usap_dc": true, "keywords": "FISH; USA/NSF; OXYGEN ISOTOPE ANALYSIS; WATER MASSES; AMD/US; AMD; USAP-DC; OXYGEN ISOTOPES; LABORATORY; Striatolamia macrota; Seymour Island; Sharks", "locations": "Seymour Island", "north": -64.209061, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e PALEOGENE \u003e EOCENE", "persons": "Kim, Sora; Scher, Howard; Huber, Matthew; Jahn, Alexandra", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "Dryad", "repositories": "Dryad", "science_programs": null, "south": -64.261795, "title": "Collaborative Research: Integrating Eocene Shark Paleoecology and Climate Modeling to reveal Southern Ocean Circulation and Antarctic Glaciation", "uid": "p0010146", "west": -56.693516}, {"awards": "1908548 Feakins, Sarah; 1908399 Bizimis, Michael", "bounds_geometry": "POLYGON((74.787 -67.27617,74.816483 -67.27617,74.845966 -67.27617,74.875449 -67.27617,74.904932 -67.27617,74.934415 -67.27617,74.963898 -67.27617,74.993381 -67.27617,75.022864 -67.27617,75.052347 -67.27617,75.08183 -67.27617,75.08183 -67.31817,75.08183 -67.36017,75.08183 -67.40217,75.08183 -67.44417,75.08183 -67.48617,75.08183 -67.52817,75.08183 -67.57017,75.08183 -67.61217,75.08183 -67.65417,75.08183 -67.69617,75.052347 -67.69617,75.022864 -67.69617,74.993381 -67.69617,74.963898 -67.69617,74.934415 -67.69617,74.904932 -67.69617,74.875449 -67.69617,74.845966 -67.69617,74.816483 -67.69617,74.787 -67.69617,74.787 -67.65417,74.787 -67.61217,74.787 -67.57017,74.787 -67.52817,74.787 -67.48617,74.787 -67.44417,74.787 -67.40217,74.787 -67.36017,74.787 -67.31817,74.787 -67.27617))", "dataset_titles": "Ejtibbett/EOTproxymodel: Proxy Model Comparison for the Eocene-Oligocene Transition [Computational Notebook]; Paleoceanography and biomarker data from the Antarctic Peninsula over the past 37-3 million years; Prydz Bay East Antarctica, biomarkers and pollen, 36-33 million years; Sabrina Coast East Antarctica, Pollen and Biomarker Data from 59-38 million years ago; Southern High Latitude Temperature Proxies from the Late Eocene and Early Oligocene [Dataset]", "datasets": [{"dataset_uid": "200259", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Sabrina Coast East Antarctica, Pollen and Biomarker Data from 59-38 million years ago", "url": "https://www.ncdc.noaa.gov/paleo/study/34772"}, {"dataset_uid": "200335", "doi": "10.5281/zenodo.7254536", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Southern High Latitude Temperature Proxies from the Late Eocene and Early Oligocene [Dataset]", "url": "https://zenodo.org/record/7254536#.Y2BLgOTMI2w"}, {"dataset_uid": "200334", "doi": "10.5281/zenodo.7254786", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Ejtibbett/EOTproxymodel: Proxy Model Comparison for the Eocene-Oligocene Transition [Computational Notebook]", "url": "https://zenodo.org/record/7254786#.Y2BLAeTMI2w"}, {"dataset_uid": "200206", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Prydz Bay East Antarctica, biomarkers and pollen, 36-33 million years", "url": "https://www.ncdc.noaa.gov/paleo-search/study/32052"}, {"dataset_uid": "200317", "doi": "10.25921/n9kg-yw91", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Paleoceanography and biomarker data from the Antarctic Peninsula over the past 37-3 million years", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/35613"}], "date_created": "Sat, 05 Dec 2020 00:00:00 GMT", "description": "The East Antarctic Ice Sheet holds the largest volume of freshwater on the planet, in total enough to raise sea level by almost two hundred feet. Even minor adjustments in the volume of ice stored have major implications for coastlines and climates around the world. The question motivating this project is how did the ice grow to cover the continent over thirty million years ago when Antarctica changed from a warmer environment to an ice-covered southern continent? The seafloor of Prydz Bay, a major drainage basin of the East Antarctic Ice Sheet (EAIS), has been drilled previously to recover sediments dating from millions of years prior to and across the time when inception of continental ice sheets occurred in Antarctica. The last remnants of plant material found as \u0027biomarkers\u0027 in the ocean sediments record the chemical signatures of rain and snowfall that fed the plants and later the expanding glaciers. Sediment carried by glaciers was also deposited on the seafloor and can be analyzed to discover how glaciers flowed across the landscape. Here, the researchers will identify precipitation changes that result from, and drive, ice sheet growth. This study will gather data and further analyze samples from the seafloor sediment archives of the International Ocean Discovery Program\u0027s (IODP) core repositories. Ultimately these findings can help inform temperature-precipitation-ice linkages within climate and ice sheet models. The project will support the training of three female, early career scientists (PhD \u0026 MS students, and research technician) and both PIs and the PhD student will continue their engagement with broadening participation efforts (e.g., Women in Science and Engineering Program; local chapters of Society for the advancement of Native Americans and Chicanos in Science and other access programs) to recruit undergraduate student participants from underrepresented minorities at both campuses and from local community colleges. Antarctic earth science education materials will be assisted by professional illustrations to be open access and used in public education and communication efforts to engage local communities in Los Angeles CA and Columbia SC. \u003cbr/\u003e\u003cbr/\u003eThe researchers at the University of Southern California and the University of South Carolina will together study the penultimate moment of the early Cenozoic greenhouse climate state: the ~4 million years of global cooling that culminated in the Eocene/Oligocene transition (~34 Ma). Significant gaps remain in the understanding of the conditions that preceded ice expansion on Antarctica. In particular, the supply of raw material for ice sheets (i.e., moisture) and the timing, frequency, and duration of precursor glaciations is poorly constrained. This collaborative proposal combines organic and inorganic proxies to examine how Antarctic hydroclimate changed during the greenhouse to icehouse transition. The central hypothesis is that the hydrological cycle weakened as cooling proceeded. Plant-wax hydrogen and carbon isotopes (hydroclimate proxies) and Hf-Nd isotopes of lithogenous and hydrogenous sediments (mechanical weathering proxies) respond strongly and rapidly to precipitation and glacial advance. This detailed and sensitive combined approach will test whether there were hidden glaciations (and/or warm events) that punctuated the pre-icehouse interval. Studies will be conducted on Prydz Bay marine sediment cores in a depositional area for products of weathering and erosion that were (and are) transported through Lambert Graben from the center of Antarctica. The project will yield proxy information about the presence of plants and the hydroclimate of Antarctica and the timing of glacial advance, and is expected to show drying associated with cooling and ice-sheet growth. The dual approach will untangle climate signals from changes in fluvial versus glacial erosion of plant biomarkers. This proposal is potentially transformative because the combination of organic and inorganic proxies can reveal rapid transitions in aridity and glacial expansion, that may have been missed in slower-response proxies and more distal archives. The research is significant as hydroclimate seems to be a key player in the temperature-cryosphere hysteresis.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 75.08183, "geometry": "POINT(74.934415 -67.48617)", "instruments": null, "is_usap_dc": true, "keywords": "MICROFOSSILS; Prydz Bay; PALEOCLIMATE RECONSTRUCTIONS; Sabrina Coast; DROUGHT/PRECIPITATION RECONSTRUCTION; ISOTOPES; AIR TEMPERATURE RECONSTRUCTION", "locations": "Prydz Bay; Sabrina Coast", "north": -67.27617, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Feakins, Sarah; Scher, Howard", "platforms": null, "repo": "NCEI", "repositories": "NCEI; Zenodo", "science_programs": null, "south": -67.69617, "title": "Collaborative Research: Organic and Inorganic Geochemical Investigation of Hydrologic Change in East Antarctica in the 4 Million Years Before Full Glaciation", "uid": "p0010143", "west": 74.787}, {"awards": "1341736 Adams, Byron", "bounds_geometry": null, "dataset_titles": "Dataset DS-TAMS: Genetic diversity of Collembola from the Transantarctic Mountains; GenBank accession numbers MN619477 to MN619610; Meteoric 10Be data of soils from the Shackleton Glacier region; Shackleton Glacier region soil water-soluble geochemical data; Shackleton Glacier region water-soluble salt isotopes; Soil invertebrate surveys from the Shackleton Glacier region of Antarctica during the 2017-2018 austral summer", "datasets": [{"dataset_uid": "200174", "doi": "10.5883/DS-TAMS", "keywords": null, "people": null, "repository": "Barcode of Life Datasystems (BOLD)", "science_program": null, "title": "Dataset DS-TAMS: Genetic diversity of Collembola from the Transantarctic Mountains", "url": "http://dx.doi.org/10.5883/DS-TAMS"}, {"dataset_uid": "601418", "doi": "10.15784/601418", "keywords": "Antarctica; Cryosphere; Geochemistry; Shackleton Glacier", "people": "Diaz, Melisa A.; Lyons, W. Berry; Gardner, Christopher B.", "repository": "USAP-DC", "science_program": null, "title": "Shackleton Glacier region soil water-soluble geochemical data", "url": "https://www.usap-dc.org/view/dataset/601418"}, {"dataset_uid": "200175", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "GenBank accession numbers MN619477 to MN619610", "url": "https://www.ncbi.nlm.nih.gov/nuccore/MN619477"}, {"dataset_uid": "601421", "doi": "10.15784/601421", "keywords": "Antarctica; Be-10; Beryllium-10; Cosmogenic Radionuclides; Cryosphere; Geochemistry; Geomorphology; Shackleton Glacier; SURFACE EXPOSURE DATES", "people": "Diaz, Melisa A.", "repository": "USAP-DC", "science_program": null, "title": "Meteoric 10Be data of soils from the Shackleton Glacier region", "url": "https://www.usap-dc.org/view/dataset/601421"}, {"dataset_uid": "200258", "doi": "doi:10.6073/pasta/7959821e5f6f8d56d94bb6a26873b3ae", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "Soil invertebrate surveys from the Shackleton Glacier region of Antarctica during the 2017-2018 austral summer", "url": "https://doi.org/10.6073/pasta/7959821e5f6f8d56d94bb6a26873b3ae"}, {"dataset_uid": "601419", "doi": "10.15784/601419", "keywords": "Antarctica; Cryosphere; Geochemistry; Nitrate; Shackleton Glacier; Stable Isotopes; Sulfate; Transantarctic Mountains", "people": "Gardner, Christopher B.; Diaz, Melisa A.; Lyons, W. Berry", "repository": "USAP-DC", "science_program": null, "title": "Shackleton Glacier region water-soluble salt isotopes", "url": "https://www.usap-dc.org/view/dataset/601419"}], "date_created": "Mon, 02 Nov 2020 00:00:00 GMT", "description": "The project will characterize the functional, taxonomic, biotic and abiotic drivers of soil ecosystems in the Trans Antarctic Mountains (one of the most remote and harsh terrestrial landscapes on the planet). The work will utilize new high-throughput DNA and RNA sequencing technologies to identify members of the microbial communities and determine if the microbial community structures are independent of local environmental heterogeneities. In addition the project will determine if microbial diversity and function are correlated with time since the last glacial maximum (LGM). The expected results will greatly contribute to our knowledge regarding rates of microbial succession and help define the some of the limits to life and life-maintaining processes on Earth.\u003cbr/\u003e\u003cbr/\u003eThe project will analyze genomes and RNA derived from these genomes to describe the relationships between biodiversity and ecosystem functioning from soils above and below LGM elevations and to correlate these with the environmental drivers associated with their development during the last ~18,000 years. The team will identify the taxonomic diversity and the functional genetic composition within a broad suite of soil biota and examine their patterns of assembly and distribution within the framework of their geological legacies. The project will mentor participants from undergraduate students to postdoctoral researchers and prepare them to effectively engage in research to meet their career aspirations. The project will contribute to ongoing public education efforts through relationships with K-12 teachers and administrators- to include University-Public School partnerships. Less formal activities include public lecture series and weblogs aimed at providing information on Antarctic polar desert ecosystems to the general public. Targeted classrooms near each PI\u0027s institution will participate in online, real-time discussions about current topics in Antarctic ecosystems research.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; AMD/US; LABORATORY; AMD; USA/NSF; TERRESTRIAL ECOSYSTEMS; Transantarctic Mountains; USAP-DC", "locations": "Transantarctic Mountains", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Adams, Byron; Fierer, Noah; Wall, Diana; Diaz, Melisa A.; Gardner, Christopher B.; Lyons, W. Berry", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "Barcode of Life Datasystems (BOLD)", "repositories": "Barcode of Life Datasystems (BOLD); EDI; NCBI GenBank; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: The Role of Glacial History on the Structure and Functioning of Ecological Communities in the Shackleton Glacier Region of the Transantarctic Mountains", "uid": "p0010140", "west": null}, {"awards": "1542962 Anderson, Robert", "bounds_geometry": "POLYGON((-171 -57,-170.8 -57,-170.6 -57,-170.4 -57,-170.2 -57,-170 -57,-169.8 -57,-169.6 -57,-169.4 -57,-169.2 -57,-169 -57,-169 -57.72,-169 -58.44,-169 -59.16,-169 -59.88,-169 -60.6,-169 -61.32,-169 -62.04,-169 -62.76,-169 -63.48,-169 -64.2,-169.2 -64.2,-169.4 -64.2,-169.6 -64.2,-169.8 -64.2,-170 -64.2,-170.2 -64.2,-170.4 -64.2,-170.6 -64.2,-170.8 -64.2,-171 -64.2,-171 -63.48,-171 -62.76,-171 -62.04,-171 -61.32,-171 -60.6,-171 -59.88,-171 -59.16,-171 -58.44,-171 -57.72,-171 -57))", "dataset_titles": "Expedition Data of NBP1702; Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean ; Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean (SNOWBIRDS)", "datasets": [{"dataset_uid": "200165", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean (SNOWBIRDS)", "url": "https://www.bco-dmo.org/dataset/813379/data"}, {"dataset_uid": "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": "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"}], "date_created": "Fri, 25 Sep 2020 00:00:00 GMT", "description": "General:\r\nScientists established more than 30 years ago that the climate-related variability of carbon dioxide levels in the atmosphere over Earth\u2019s ice-age cycles was regulated by the ocean. Hypotheses to explain how the ocean that regulates atmospheric carbon dioxide have long been debated, but they have proven to be difficult to test. This project was designed test one leading hypothesis, specifically that the ocean experienced greater density stratification during the ice ages. That is, with greater stratification during the ice ages and the slower replacement of deep water by cold dense water formed near the poles, the deep ocean would have held more carbon dioxide, which is produced by biological respiration of the organic carbon that constantly rains to the abyss in the form of dead organisms and organic debris that sink from the sunlit surface ocean. To test this hypothesis, the degree of ocean stratification during the last ice age and the rate of deep-water replacement was to be constrained by comparing the radiocarbon ages of organisms that grew in the surface ocean and at the sea floor within a critical region around Antarctica, where most of the replacement of deep waters occurs. Completing this work was expected to contribute toward improved models of future climate change. Climate scientists rely on models to estimate the amount of fossil fuel carbon dioxide that will be absorbed by the ocean in the future. Currently the ocean absorbs about 25% of the carbon dioxide produced by burning fossil fuels. Most of this carbon is absorbed in the Southern Ocean (the region around Antarctica). How this will change in the future is poorly known. Models have difficulty representing physical conditions in the Southern Ocean accurately, thereby adding substantial uncertainty to projections of future ocean uptake of carbon dioxide. Results of the proposed study will provide a benchmark to test the ability of models to simulate ocean processes under climate conditions distinctly different from those that occur today, ultimately leading to improvement of the models and to more reliable projections of future absorption of carbon dioxide by the ocean. \r\n\r\nTechnical:\r\nThe project added a research component to an existing scientific expedition to the Southern Ocean, in the region between the Ross Sea and New Zealand, that collected sediment cores at locations down the northern flank of the Pacific-Antarctic Ridge at approximately 170\u00b0W. The goal was to collect sediments at each location deposited since early in the peak of the last ice age. This region is unusual in the Southern Ocean in that sediments deposited during the last ice age contain foraminifera, tiny organisms with calcium carbonate shells, in much greater abundance than in other regions of the Southern Ocean. Foraminifera are widely used as an archive of several geochemical tracers of past ocean conditions. We proposed to compare the radiocarbon age of foraminifera that inhabited the surface ocean with the age of contemporary specimens that grew on the seabed. The difference in age between surface and deep-swelling organisms would have been used to discriminate between two proposed mechanisms of deep water renewal during the ice age: formation in coastal polynyas around the edge of Antarctica, much as occurs today, versus formation by open-ocean convection in deep-water regions far from the continent. If the latter mechanism prevails, then it was expected that surface and deep-dwelling foraminifera would exhibit similar radiocarbon ages. In the case of dominance of deep-water formation in coastal polynyas, one expects to find very different radiocarbon ages in the two populations of foraminifera. In the extreme case of greater ocean stratification during the last ice age, one even expects the surface dwellers to appear to be older than contemporary bottom dwellers because the targeted core sites lie directly under the region where the oldest deep waters outcrop at the surface following their long circuitous transit through the deep ocean. The primary objective of the proposed work was to reconstruct the water mass age structure of the Southern Ocean during the last ice age, which, in turn, is a primary factor that controls the amount of carbon dioxide stored in the deep sea. In addition, the presence of foraminifera in the cores to be recovered provides a valuable resource for many other paleoceanographic applications, such as: 1) the application of nitrogen isotopes to constrain the level of nutrient utilization in the Southern Ocean and, thus, the efficiency of the ocean\u2019s biological pump, 2) the application of neodymium isotopes to constrain the transport history of deep water masses, 3) the application of boron isotopes and boron/calcium ratios to constrain the pH and inorganic carbon system parameters of ice-age seawater, and 4) the exploitation of metal/calcium ratios in foraminifera to reconstruct the temperature (Mg/Ca) and nutrient content (Cd/Ca) of deep waters during the last ice age at a location near their source near Antarctica. \r\n\r\nUnfortunately, the cores were shipped to the core repository in a horizontal orientation and there was sufficient distortion of the sediment that the radiocarbon ages of benthic foraminifera were uninterpretable. Therefore, we report only the radiocarbon dates for planktonic foraminifera as well as the total counts of elemental relative abundance from X-ray Fluorescence analysis of the cores. In addition, we used the expedition as an opportunity to collect water samples from which dissolved concentrations of long-lived isotope of thorium and protactinium were determined. Results from those analyses showed that lateral transport by isopycnal mixing dominates the supply of Pa to the Southern Ocean. We have also developed a new algorithm to correct for supply of Th by isopycnal mixing and thereby derive estimates of dust flux to the Southern Ocean. \r\n", "east": -169.0, "geometry": "POINT(-170 -60.6)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; SEDIMENT CHEMISTRY; South Pacific Ocean; SHIPS", "locations": "South Pacific Ocean", "north": -57.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, Robert; Fleisher, Martin; Pavia, Frank", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "BCO-DMO", "repositories": "BCO-DMO; NCEI; R2R", "science_programs": null, "south": -64.2, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean", "uid": "p0010130", "west": -171.0}, {"awards": "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; Cryosphere; Detrital Minerals; 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": "601377", "doi": "10.15784/601377", "keywords": "40Ar/39Ar thermochronology; Antarctica; Argon; Chemistry:Sediment; Cryosphere; Detrital Minerals; 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"}, {"dataset_uid": "601379", "doi": "10.15784/601379", "keywords": "40Ar/39Ar thermochronology; Antarctica; Argon; Chemistry:Sediment; Cryosphere; Detrital Minerals; 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"}], "date_created": "Thu, 10 Sep 2020 00:00:00 GMT", "description": "Abstract for the general public:\u003cbr/\u003e\u003cbr/\u003eThe 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. \u003cbr/\u003e\u003cbr/\u003eThe 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: \u003cbr/\u003e\u003cbr/\u003e1. 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. \u003cbr/\u003e\u003cbr/\u003e2. 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. \u003cbr/\u003e\u003cbr/\u003eTechnical abstract:\u003cbr/\u003e\u003cbr/\u003e 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. \u003cbr/\u003e\u003cbr/\u003eGeochemical 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: \u003cbr/\u003e\u003cbr/\u003e1. 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. \u003cbr/\u003e\u003cbr/\u003e2. 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; AMD/US; Subglacial Till; USAP-DC; ICEBERGS; AMD; USA/NSF; ISOTOPES; AGE DETERMINATIONS; Argon; Provenance; Till; 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": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V POLARSTERN; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "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; 1935945 Tremblay, Marissa; 1935907 Balco, Gregory", "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\r\nScientists 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 proxy, 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 \u00baC 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 proxy 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. \r\n\r\nPart II: Technical Description\r\nThe mid-Pliocene Warm Period (3\u20133.3 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 Earths 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 Earths 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.", "east": 164.0, "geometry": "POINT(162 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; AMD/US; AMD; LABORATORY; USA/NSF; 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": "1543441 Fricker, Helen; 1543405 Leventer, Amy; 1543453 Lyons, W. Berry; 1543396 Christner, Brent; 1543537 Priscu, John; 1543347 Rosenheim, Brad", "bounds_geometry": "POLYGON((-163.611 -84.33543,-162.200034 -84.33543,-160.789068 -84.33543,-159.378102 -84.33543,-157.967136 -84.33543,-156.55617 -84.33543,-155.145204 -84.33543,-153.734238 -84.33543,-152.323272 -84.33543,-150.912306 -84.33543,-149.50134 -84.33543,-149.50134 -84.3659157,-149.50134 -84.3964014,-149.50134 -84.4268871,-149.50134 -84.4573728,-149.50134 -84.4878585,-149.50134 -84.5183442,-149.50134 -84.5488299,-149.50134 -84.5793156,-149.50134 -84.6098013,-149.50134 -84.640287,-150.912306 -84.640287,-152.323272 -84.640287,-153.734238 -84.640287,-155.145204 -84.640287,-156.55617 -84.640287,-157.967136 -84.640287,-159.378102 -84.640287,-160.789068 -84.640287,-162.200034 -84.640287,-163.611 -84.640287,-163.611 -84.6098013,-163.611 -84.5793156,-163.611 -84.5488299,-163.611 -84.5183442,-163.611 -84.4878585,-163.611 -84.4573728,-163.611 -84.4268871,-163.611 -84.3964014,-163.611 -84.3659157,-163.611 -84.33543))", "dataset_titles": "Antarctica - PI Continuous - GZ01-WIS_GroundingZone_01 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - GZ13-WIS_GroundingZone_13 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA02-WIS_LAKES_02 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA06-WIS_LAKES_06 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA07-WIS_LAKES_07 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA09-WIS_LAKES_09 P.S. - GPS/GNSS Observations Dataset; Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland; CTD data from Mercer Subglacial Lake and access borehole; Discrete bulk sediment properties data from Mercer Subglacial Lake; Isotopic data from Whillans Ice Stream grounding zone, West Antarctica; Mercer Subglacial Lake radiocarbon and stable isotope data ; Mercer Subglacial Lake (SLM) microbial composition: 16S rRNA genes (Sequence Read Archive; BioProject: PRJNA790995); Mercer Subglacial Lake (SLM) noble gas and isotopic data; Mercer Subglacial Lake water column viral metagenomic sequencing; Salsa sediment cores; Sediment porewater properties data from Mercer Subglacial Lake; Water column biogeochemical data from Mercer Subglacial Lake", "datasets": [{"dataset_uid": "200246", "doi": "", "keywords": null, "people": null, "repository": "OSU-MGR", "science_program": null, "title": "Salsa sediment cores", "url": "https://osu-mgr.org"}, {"dataset_uid": "601498", "doi": "10.15784/601498", "keywords": "Antarctica; Cryosphere; Mercer Subglacial Lake; Noble Gas", "people": "Gardner, Christopher B.; Lyons, W. Berry", "repository": "USAP-DC", "science_program": null, "title": "Mercer Subglacial Lake (SLM) noble gas and isotopic data", "url": "https://www.usap-dc.org/view/dataset/601498"}, {"dataset_uid": "601472", "doi": "10.15784/601472", "keywords": "Antarctica; Bistatic Radar; Cryosphere; Glaciers/Ice Sheet; Glaciology; GPS Data; Greenland; Lake Whillans; Radar; Store Glacier; Whillans Ice Stream; WISSARD", "people": "MacKie, Emma; Christoffersen, Poul; Dawson, Eliza; Schroeder, Dustin; Bienert, Nicole; Peters, Sean; Siegfried, Matthew", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland", "url": "https://www.usap-dc.org/view/dataset/601472"}, {"dataset_uid": "200217", "doi": "10.7283/3JMY-Y504", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA09-WIS_LAKES_09 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/3JMY-Y504"}, {"dataset_uid": "200216", "doi": "10.7283/F8NH-CV04", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA07-WIS_LAKES_07 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/F8NH-CV04"}, {"dataset_uid": "200215", "doi": "10.7283/C503-KS23", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA06-WIS_LAKES_06 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/C503-KS23"}, {"dataset_uid": "200214", "doi": "10.7283/YW8Z-TK03", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA02-WIS_LAKES_02 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/YW8Z-TK03"}, {"dataset_uid": "200213", "doi": "10.7283/F7BB-JH05", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - GZ13-WIS_GroundingZone_13 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/F7BB-JH05"}, {"dataset_uid": "200212", "doi": "10.7283/PT0Q-JB95", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - GZ01-WIS_GroundingZone_01 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/PT0Q-JB95"}, {"dataset_uid": "601360", "doi": "10.15784/601360", "keywords": "Antarctica; Cryosphere; Radiocarbon; Sediment; Whillans Ice Stream", "people": "Venturelli, Ryan A", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Isotopic data from Whillans Ice Stream grounding zone, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/601360"}, {"dataset_uid": "601672", "doi": "10.15784/601672", "keywords": "Antarctica; Cryosphere; isotopes; Mercer Subglacial Lake; Radiocarbon; Subglacial lakes", "people": "Venturelli, Ryan; Rosenheim, Brad", "repository": "USAP-DC", "science_program": null, "title": "Mercer Subglacial Lake radiocarbon and stable isotope data ", "url": "https://www.usap-dc.org/view/dataset/601672"}, {"dataset_uid": "601664", "doi": "10.15784/601664", "keywords": "Antarctica; Cryosphere; gases; geochemistry; Glacier; Glaciology; Mercer Subglacial Lake; Methane; SALSA; Sediment Core; West Antarctic Ice Sheet", "people": "Michaud, Alexander; Dore, John; Science Team, SALSA; Steigmeyer, August; Tranter, Martyn; Skidmore, Mark", "repository": "USAP-DC", "science_program": null, "title": "Sediment porewater properties data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601664"}, {"dataset_uid": "200342", "doi": null, "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Mercer Subglacial Lake water column viral metagenomic sequencing", "url": "https://www.ncbi.nlm.nih.gov/biosample/32811410"}, {"dataset_uid": "200282", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Mercer Subglacial Lake (SLM) microbial composition: 16S rRNA genes (Sequence Read Archive; BioProject: PRJNA790995)", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA790995"}, {"dataset_uid": "601663", "doi": "10.15784/601663", "keywords": "Antarctica; Carbon; Cell Counts; Cryosphere; geochemistry; Glacier; Glaciers/Ice Sheet; Mercer Subglacial Lake; Microbes; Nutrients; SALSA; Stable Isotopes; Trace Elements; West Antarctic Ice Sheet", "people": "Barker, Joel; Dore, John; Skidmore, Mark; Hawkings, Jon; Steigmeyer, August; Science Team, SALSA; Priscu, John; Tranter, Martyn; Li, Wei", "repository": "USAP-DC", "science_program": null, "title": "Water column biogeochemical data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601663"}, {"dataset_uid": "601661", "doi": "10.15784/601661", "keywords": "Antarctica; Carbon; Cryosphere; Glacier; Glaciers/Ice Sheet; Iron; Mercer Subglacial Lake; Mineralogy; Particle Size; physical properties; SALSA; Sediment Core; sulfur; West Antarctic Ice Sheet", "people": "Hawkings, Jon; Science Team, SALSA; Venturelli, Ryan A; Tranter, Martyn; Skidmore, Mark; Michaud, Alexander; Campbell, Timothy; Dore, John", "repository": "USAP-DC", "science_program": null, "title": "Discrete bulk sediment properties data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601661"}, {"dataset_uid": "601657", "doi": "10.15784/601657", "keywords": "Antarctica; Conductivity; Cryosphere; CTD; Depth; Glaciers/Ice Sheet; Glaciology; Hot Water Drill; Mercer Subglacial Lake; physical properties; SALSA; subglacial lake; Temperature", "people": "Priscu, John; Dore, John; Leventer, Amy; Rosenheim, Brad", "repository": "USAP-DC", "science_program": null, "title": "CTD data from Mercer Subglacial Lake and access borehole", "url": "https://www.usap-dc.org/view/dataset/601657"}], "date_created": "Thu, 16 Jul 2020 00:00:00 GMT", "description": "The Antarctic subglacial environment remains one of the least explored regions on Earth. This project will examine the physical and biological characteristics of Subglacial Lake Mercer, a lake that lies 1200m beneath the West Antarctic Ice Sheet. This study will address key questions relating to the stability of the ice sheet, the subglacial hydrological system, and the deep-cold subglacial biosphere. The education and outreach component aims to widely disseminate results to the scientific community and to the general public through short films, a blog, and a website.\u003cbr/\u003e\u003cbr/\u003eSubglacial Lake Mercer is one of the larger hydrologically active lakes in the southern basin of the Whillans Ice Plain, West Antarctica. It receives about 25 percent of its water from East Antarctica with the remainder originating from West Antarctica, is influenced by drain/fill cycles in a lake immediately upstream (Subglacial Lake Conway), and lies about 100 km upstream of the present grounding line of the Ross Ice Shelf. This site will yield information on the history of the Whillans and Mercer Ice Streams, and on grounding line migration. The integrated study will include direct sampling of basal ice, water, and sediment from the lake in concert with surface geophysical surveys over a three-year period to define the hydrological connectivity among lakes on the Whillans Ice Plain and their flow paths to the sea. The geophysical surveys will furnish information on subglacial hydrology, aid the site selection for hot-water drilling, and provide spatial context for interpreting findings. The hot-water-drilled boreholes will be used to collect basal ice samples, provide access for direct measurement of subglacial physical, chemical, and biological conditions in the water column and sediments, and to explore the subglacial water cavities using a remotely operated vehicle equipped with sensors, cameras, and sampling equipment. Data collected from this study will address the overarching hypothesis \\\"Contemporary biodiversity and carbon cycling in hydrologically-active subglacial environments associated with the Mercer and Whillans ice streams are regulated by the mineralization and cycling of relict marine organic matter and through interactions among ice, rock, water, and sediments\\\". The project will be undertaken by a collaborative team of scientists, with expertise in microbiology, biogeochemistry, hydrology, geophysics, glaciology, marine geology, paleoceanography, and science communication.", "east": -149.50134, "geometry": "POINT(-156.55617 -84.4878585)", "instruments": null, "is_usap_dc": true, "keywords": "SEDIMENTS; Antarctica; ISOTOPES; USAP-DC; VIRUSES; PALEOCLIMATE RECONSTRUCTIONS; BACTERIA/ARCHAEA; LABORATORY; Radiocarbon; Whillans Ice Stream; AMD; SALSA; ECOSYSTEM FUNCTIONS; RADIOCARBON; FIELD INVESTIGATION; AMD/US; ICE MOTION; subglacial lake; Mercer Ice Stream; USA/NSF; GLACIERS/ICE SHEETS", "locations": "Antarctica; Mercer Ice Stream; Whillans Ice Stream", "north": -84.33543, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Instrumentation and Support; Antarctic Integrated System Science", "paleo_time": null, "persons": "Rosenheim, Brad; Fricker, Helen; Priscu, John; Leventer, Amy; Dore, John; Lyons, W. Berry; Christner, Brent", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "OSU-MGR", "repositories": "GenBank; NCBI GenBank; OSU-MGR; UNAVCO; USAP-DC", "science_programs": null, "south": -84.640287, "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "uid": "p0010119", "west": -163.611}, {"awards": "1443482 Mak, John", "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": "Carbon monoxide mixing ratios and stable isotopic values, SPICE", "datasets": [{"dataset_uid": "601356", "doi": "10.15784/601356", "keywords": "Antarctica; CO; Cryosphere; Delta 13C; Delta 18O; South Pole; SPICECORE", "people": "Mak, John", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Carbon monoxide mixing ratios and stable isotopic values, SPICE", "url": "https://www.usap-dc.org/view/dataset/601356"}], "date_created": "Thu, 09 Jul 2020 00:00:00 GMT", "description": "The investigators plan to reconstruct historical variations in the sources of atmospheric carbon monoxide (CO) from measurements of the concentration and stable isotopic abundance of carbon monoxide ([CO], 13CO and C18O) in the South Pole Ice Core, which is being drilled in 2014-2016. The goal is to strategically sample and reconstruct the relative variations in CO source strengths over the past 20,000 years. These will be the first measurements to extend the CO record beyond 650 years before present, back to the last glacial maximum. Both atmospheric chemical processes and variations in CO sources can impact the CO budget, and variations in the CO budget are useful in identifying and quantifying chemistry-climate interactions.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "LABORATORY; TRACE GASES/TRACE SPECIES; FIELD INVESTIGATION; South Pole", "locations": "South Pole", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Mak, John", "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: Using Stable Isotopes to Constrain the Atmospheric Carbon Monoxide Budget over the Last 20,000 Years", "uid": "p0010117", "west": -180.0}, {"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; Cryosphere; 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.\r\nTo test model predictions,sub-glacial rock cores were obtained from the Ohio Range along the Transantarctic Mountains near the present-day WAIS divide using a Winkie drill. Rock cores were recovered from 10 to ~30 m under the present-day ice levels. At the Ohio Range, the glacial to interglacial variations in ice sheet levels is ~120 meters. So 30 meters represent a significant fraction of the variation over the course of an ice age.\r\nHigh concentrations of the cosmic ray produced isotopes were detected in the rock cores, indicating extensive periods of ice-free exposure to cosmic irradiation during the last 2 million years. Modeling of the data suggest that bedrock surfaces at the Ohio Range that are currently covered by 30 meters of ice experienced more exposure than ice cover, especially in the Pleistocene. An ice sheet model prediction for the Ohio Range subglacial sample sites however, significantly underestimates exposure in the last 2 million years, and over-predicts ice cover in the Pleistocene. To adjust for the higher amounts of exposure we observe in our samples, the ice sheet model simulations require more frequent and/or longer-lasting WAIS ice drawdowns. This has important implications for future sea-level change as the model maybe under-predicting the magnitude of sea-level contributions from WAIS during the ice-age cycles. Improving the accuracy of the ice sheet models through model-data comparison should remain a prime objective in the face of a warming planet as understanding WAIS behavior is going to be key for predicting and planning for the effects of sea-level change. The project helped support and train a graduate student in climate research related to Antarctica, cosmogenic nuclide analyses and led to a Master\u2019s Thesis. The project also provide partial support to a postdoctoral scholar obtaining cosmogenic neon measurements and for training and mentoring the graduate student\u0027s cosmogenic neon measurements and interpretation. The project results were communicated to the scientific community at conferences and through seminars. The broader community was engaged through the University of California Davis\u0027s Picnic Day celebration, an annual open house that attracts over 70,000 people to the campus, and through classroom visit at a local elementary school.", "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": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "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": "1246465 Brook, Edward", "bounds_geometry": "POINT(-112.1115 -79.481)", "dataset_titles": "WAIS Divide Ice Core Marine Isotope Stage 3 CO2 record", "datasets": [{"dataset_uid": "601337", "doi": "10.15784/601337", "keywords": "Antarctica; Carbon Cycle; CO2; Cryosphere; Gas Chromatograph; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; WAIS divide", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice Core Marine Isotope Stage 3 CO2 record", "url": "https://www.usap-dc.org/view/dataset/601337"}], "date_created": "Mon, 22 Jun 2020 00:00:00 GMT", "description": "This award supports a project to measure the carbon dioxide (CO2) concentration in the WAIS Divide ice core covering the time period 25,000 to 60,000 years before present, and to analyze the isotopic composition of CO2 in selected time intervals. The research will improve understanding of how and why atmospheric CO2 varied during the last ice age, focusing particularly on abrupt transitions in the concentration record that are associated with abrupt climate change. These events represents large perturbations to the global climate system and better information about the CO2 response should inform our understanding of carbon cycle-climate feedbacks and radiative forcing of climate. The research will also improve analytical methods in support of these goals, including completing development of sublimation methods to replace laborious mechanical crushing of ice to release air for analysis. The intellectual merit of the proposed work is that it will increase knowledge about the magnitude and timing of atmospheric CO2 variations during the last ice age, and their relationship to regional climate in Antarctica, global climate history, and the history of abrupt climate change in the Northern Hemisphere. The temporal resolution of the proposed record will in most intervals be ~ 4 x higher than previous data sets for this time period, and for selected intervals up to 8-10 times higher. Broader impacts of the proposed work include a significant addition to the amount of data documenting the history of the most important long-lived greenhouse gas in the atmosphere and more information about carbon cycle-climate feedbacks - important parameters for predicting future climate change. The project will contribute to training a postdoctoral researcher, research experience for an undergraduate and a high school student, and outreach to local middle school and other students. It will also improve the analytical infrastructure at OSU, which will be available for future projects.", "east": -112.1115, "geometry": "POINT(-112.1115 -79.481)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Ice Core Records; USAP-DC; CO2; FIELD INVESTIGATION; CARBON DIOXIDE; WAIS divide; LABORATORY; Carbon Cylce", "locations": "WAIS divide", "north": -79.481, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "Completing the WAIS Divide Ice Core CO2 record", "uid": "p0010110", "west": -112.1115}, {"awards": "1443576 Panter, Kurt", "bounds_geometry": "POLYGON((-154.1 -86.9,-154.03 -86.9,-153.96 -86.9,-153.89 -86.9,-153.82 -86.9,-153.75 -86.9,-153.68 -86.9,-153.61 -86.9,-153.54 -86.9,-153.47 -86.9,-153.4 -86.9,-153.4 -86.92,-153.4 -86.94,-153.4 -86.96,-153.4 -86.98,-153.4 -87,-153.4 -87.02,-153.4 -87.04,-153.4 -87.06,-153.4 -87.08,-153.4 -87.1,-153.47 -87.1,-153.54 -87.1,-153.61 -87.1,-153.68 -87.1,-153.75 -87.1,-153.82 -87.1,-153.89 -87.1,-153.96 -87.1,-154.03 -87.1,-154.1 -87.1,-154.1 -87.08,-154.1 -87.06,-154.1 -87.04,-154.1 -87.02,-154.1 -87,-154.1 -86.98,-154.1 -86.96,-154.1 -86.94,-154.1 -86.92,-154.1 -86.9))", "dataset_titles": "Volcanological and Petrological measurements on Mt. Early and Sheridan Bluff volcanoes, upper Scott Glacier, Antarctica ", "datasets": [{"dataset_uid": "601331", "doi": "10.15784/601331", "keywords": "Antarctica; Chemistry:Rock; Geochronology; Glacial Volcanism; Magma Differentiation; Major Elements; Mantle Melting; Solid Earth; Trace Elements; Transantarctic Mountains", "people": "Panter, Kurt", "repository": "USAP-DC", "science_program": null, "title": "Volcanological and Petrological measurements on Mt. Early and Sheridan Bluff volcanoes, upper Scott Glacier, Antarctica ", "url": "https://www.usap-dc.org/view/dataset/601331"}], "date_created": "Fri, 05 Jun 2020 00:00:00 GMT", "description": "Predictions of future sea level rise require better understanding of the changing dynamics of the Greenland and Antarctic ice sheets. One way to better understand the past history of the ice sheets is to obtain records from inland ice for past geological periods, particularly in Antarctica, the world\u0027s largest remaining ice sheet. Such records are exceedingly rare, and can be acquired at volcanic outcrops in the La Gorce Mountains of the central Transantarctic Mountains. Volcanoes now exposed within the La Gorce Mountains erupted beneath the East Antarctic ice sheet and the data collected will record how thick the ice sheet was in the past. In addition, information will be used to determine the thermal conditions at the base of the ice sheet, which impacts ice sheet stability. The project will also investigate the origin of volcanic activity in Antarctica and links to the West Antarctic Rift System (WARS). The WARS is a broad area of extended (i.e. stretched) continental crust, similar to that found in East Africa, and volcanism is wide spread and long-lived (65 million years to currently active) and despite more than 50 years of research, the fundamental cause of volcanism and rifting in Antarctica is still vigorously debated. The results of this award therefore also potentially impact the study of oceanic volcanism in the entire southwestern Pacific region (e.g., New Zealand and Australia), where volcanic fields of similar composition and age have been linked by common magma sources and processes. The field program includes a graduate student who will work on the collection, analysis, and interpretation of petrological data as part of his/her Masters project. The experience and specialized analytical training being offered will improve the quality of the student\u0027s research and optimize their opportunities for their future. The proposed work fosters faculty and student national and international collaboration, including working with multi-user facilities that provide advanced technological mentoring of science students. Results will be broadly disseminated in peer-reviewed journals, public presentations at science meetings, and in outreach activities. Petrologic and geochemical data will be disseminated to be the community through the Polar Rock Repository. The study of subglacially erupted volcanic rocks has been developed to the extent that it is now the most powerful proxy methodology for establishing precise \u0027snapshots\u0027 of ice sheets, including multiple critical ice parameters. Such data should include measurements of ice thickness, surface elevation and stability, which will be used to verify, or reject, published semi-empirical models relating ice dynamics to sea level changes. In addition to establishing whether East Antarctic ice was present during the formation of the volcanoes, data will be used to derive the coeval ice thicknesses, surface elevations and basal thermal regime(s) in concert with a precise new geochronology using the 40Ar/39Ar dating method. Inferences from measurement of standard geochemical characteristics (major, trace elements and Sr, Nd, Pb, O isotopes) will be used to investigate a possible relationship between the volcanoes and the recently discovered subglacial ridge under the East Antarctic ice, which may be a rift flank uplift. The ridge has never been sampled, is undated and its significance is uncertain. The data will provide important new information about the deep Earth and geodynamic processes beneath this mostly ice covered and poorly understood sector of the Antarctic continent.", "east": -153.4, "geometry": "POINT(-153.75 -87)", "instruments": null, "is_usap_dc": true, "keywords": "Magma Differntiation; FIELD INVESTIGATION; Mantle Melting; Geochronology; Glacial Volcanism; GEOCHEMISTRY; Major Elements; ISOTOPES; Trace Elements; Transantarctic Mountains; LABORATORY; LAVA COMPOSITION/TEXTURE; USAP-DC; LAND RECORDS", "locations": "Transantarctic Mountains", "north": -86.9, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Panter, Kurt", "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": -87.1, "title": "Investigating Early Miocene Sub-ice Volcanoes in Antarctica for Improved Modeling and understanding of a Large Magmatic Province", "uid": "p0010105", "west": -154.1}, {"awards": "1744570 Galloway, Aaron; 1744550 Amsler, Charles; 1744584 Klein, Andrew; 1744602 Iken, Katrin", "bounds_geometry": "POLYGON((-70 -61,-69 -61,-68 -61,-67 -61,-66 -61,-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-60 -61.772,-60 -62.544,-60 -63.316,-60 -64.088,-60 -64.86,-60 -65.632,-60 -66.404,-60 -67.176,-60 -67.948,-60 -68.72,-61 -68.72,-62 -68.72,-63 -68.72,-64 -68.72,-65 -68.72,-66 -68.72,-67 -68.72,-68 -68.72,-69 -68.72,-70 -68.72,-70 -67.948,-70 -67.176,-70 -66.404,-70 -65.632,-70 -64.86,-70 -64.088,-70 -63.316,-70 -62.544,-70 -61.772,-70 -61))", "dataset_titles": "Average global horizontal solar irradiance at study sites; Carbon and nitrogen isotope data along a gradient at the Antarctic Peninsula; 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 ; 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": "601654", "doi": "10.15784/601654", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; 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": "601651", "doi": "10.15784/601651", "keywords": "Antarctica; Antarctic Peninsula; Biosphere; Cryosphere; 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; Cryosphere; LMG1904; National Ice Center Charts; Sea Ice Concentrations", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Five year mean annual and summer sea ice concentration grids for the Western Antarctic Peninsula from AMSR2, National Ice Center Charts and the Sea Ice Index ", "url": "https://www.usap-dc.org/view/dataset/601649"}, {"dataset_uid": "601643", "doi": "10.15784/601643", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; LMG1904; National Ice Center Charts; R/V Laurence M. Gould; Sea Ice Concentrations", "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": "601642", "doi": "10.15784/601642", "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Cryosphere; LMG1904; R/V Laurence M. Gould; Sea Ice Concentrations", "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": "601641", "doi": "10.15784/601641", "keywords": "Antarctica; Average Global Horizontal Solar Irradiance; Biology; Biosphere; Cryosphere; 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": "601640", "doi": "10.15784/601640", "keywords": "Antarctica; Biology; Biosphere; Cryosphere; 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": "601639", "doi": "10.15784/601639", "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Cryosphere; 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": "601619", "doi": "10.15784/601619", "keywords": "Antarctica; Antarctic Peninsula; benthic communities; Biology; Biosphere; Cryosphere; 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": "601610", "doi": "10.15784/601610", "keywords": "Antarctica; Antarctic Peninsula; benthic communities; Biology; Biosphere; Cryosphere; Macroalgae; 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": "601330", "doi": "10.15784/601330", "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Cryosphere; 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": "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": "601653", "doi": "10.15784/601653", "keywords": "Antarctica; Antarctic Peninsula; Biology; Carbon; Carbon Isotopes; Cryosphere; 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": "601725", "doi": "10.15784/601725", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere", "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"}], "date_created": "Thu, 04 Jun 2020 00:00:00 GMT", "description": "The western Antarctic Peninsula has become a model for understanding cold water communities and how they may be changing in Antarctica and elsewhere. Brown macroalgae (seaweeds) form extensive undersea forests in the northern portion of this region where they play a key role in providing both physical structure and a food (carbon) source for shallow water communities. Yet between Anvers Island (64 degrees S latitude) and Adelaide Island (67 S latitude) these macroalgae become markedly less abundant and diverse. This is probably because the habitat to the south is covered by more sea ice for a longer period, and the sea ice reduces the amount of light that reaches the algae. The reduced macroalgal cover undoubtedly impacts other organisms in the food web, but the ways in which it alters sea-floor community processes and organization is unknown. This project will quantitatively document the macroalgal communities at multiple sites between Anvers and Adelaide Islands using a combination of SCUBA diving, video surveys, and algal collections. Sea ice cover, light levels, and other environmental parameters on community structure will be modelled to determine which factors have the largest influence. Impacts on community structure, food webs, and carbon flow will be assessed through a mixture of SCUBA diving and video surveys. Broader impacts include the training of graduate students and a postdoctoral researcher, as well as numerous informal public education activities including lectures, presentations to K-12 groups, and a variety of social media-based outreach.\u003cbr/\u003e\u003cbr/\u003eMacroalgal communities are more abundance and diverse to the north along the Western Antarctic Peninsula, perhaps due to the greater light availability that is associated with shorter period of sea-ice cover. This project will determine the causes and community level consequence of this variation in algal community structure. First, satellite data on sea ice extent and water turbidity will be used to select study sites between 64 S and 69 S where the extent of annual sea ice cover is the primary factor influencing subsurface light levels. Then, variations in macroalgal cover across these study sites will be determined by video line-transect surveys conducted by SCUBA divers. The health, growth, and physiological status of species found at the different sites will be determined by quadrat sampling. The relative importance of macroalgal-derived carbon to the common invertebrate consumers in the foodweb will be assessed with stable isotope and fatty acid biomarker techniques. This will reveal how variation in macroalgal abundance and species composition across the sea ice cover gradient impacts sea floor community composition and carbon flow throughout the food web. In combination, this work will facilitate predictions of how the ongoing reductions in extent and duration of sea ice cover that is occurring in the region as a result of global climate change will impact the structure of nearshore benthic communities.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -60.0, "geometry": "POINT(-65 -64.86)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "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", "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": "1807522 Jones, Tyler", "bounds_geometry": "POINT(-112.085 -79.467)", "dataset_titles": "Mid-Holocene high-resolution water isotope time series for the WAIS Divide ice core; Seasonal temperatures in West Antarctica during the Holocene ; Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "datasets": [{"dataset_uid": "601274", "doi": "10.15784/601274", "keywords": "Antarctica; Cryosphere; Delta 18O; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Snow/Ice; WAIS divide; WAIS Divide Ice Core; West Antarctic Ice Sheet", "people": "Jones, Tyler R.; Bradley, Elizabeth; Morris, Valerie; White, James; Vaughn, Bruce; Garland, Joshua; Price, Michael", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "url": "https://www.usap-dc.org/view/dataset/601274"}, {"dataset_uid": "601326", "doi": "10.15784/601326", "keywords": "Antarctica; Cryosphere; Delta 18O; Delta Deuterium; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Snow/Ice; WAIS Divide Ice Core; Water Isotopes; West Antarctic Ice Sheet", "people": "White, James; Morris, Valerie; Jones, Tyler R.; Vaughn, Bruce", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Mid-Holocene high-resolution water isotope time series for the WAIS Divide ice core", "url": "https://www.usap-dc.org/view/dataset/601326"}, {"dataset_uid": "601603", "doi": "10.15784/601603", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; ice cores; Seasonality; Seasonal Temperatures; Temperature; Water Isotopes; West Antarctic Ice Sheet", "people": "Jones, Tyler R.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Seasonal temperatures in West Antarctica during the Holocene ", "url": "https://www.usap-dc.org/view/dataset/601603"}], "date_created": "Tue, 26 May 2020 00:00:00 GMT", "description": "Ice cores contain detailed accounts of Earth\u0027s climate history. The collection of an ice core can be logistically challenging, and extraction of data from the core can be time-consuming as well as susceptible to both human and machine error. Furthermore, locked in measurements from ice cores is information that scientists have not yet found ways to recover. This project will apply techniques from information theory to ice-core data to unlock that information. The primary goal is to demonstrate that information theory can (a) identify regions of a specific ice-core record that are in need of further analysis and (b) provide some specific guidance for that analysis. A secondary goal is to demonstrate that information theory has practical and scientific utility for studies of past climate. This project aims to use information theory in two distinct ways: first, to identify regions of a core where information appears to be damaged or missing, perhaps due to human and/or machine error. In the segment of the West Antarctic Ice Sheet Divide core that is 5000-8000 years old, for instance, information-theoretic methods reveal significant levels of noise, probably due to a laboratory instrument, and something that was not visible in the raw data. This is a particularly important segment of the record, as it contains valuable clues about climatic shifts and the onset of the Holocene. Targeted re-sampling of this segment of the core and reanalysis with newer laboratory apparatus could resolve the data issues. The second way in which information theory can potentially aid in ice-core analysis is by extracting climate signals from the data--such as the accumulation rate at the core site over the period of its formation. This quantity usually requires significant time and effort to produce, but information theory could help to streamline that process.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": -112.085, "geometry": "POINT(-112.085 -79.467)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "AMD; AMD/US; West Antarctic Ice Sheet; ISOTOPES; USAP-DC; USA/NSF; Water Isotopes; Deuterium; WAIS Divide Ice Cores; LABORATORY", "locations": "West Antarctic Ice Sheet", "north": -79.467, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Garland, Joshua; Jones, Tyler R.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.467, "title": "Collaborative Research: Targeted resampling of deep polar ice cores using information theory", "uid": "p0010100", "west": -112.085}, {"awards": "1142035 Obbard, Rachel; 1142167 Pettit, Erin", "bounds_geometry": "POLYGON((-112.3 -79.2,-112.2 -79.2,-112.1 -79.2,-112 -79.2,-111.9 -79.2,-111.8 -79.2,-111.7 -79.2,-111.6 -79.2,-111.5 -79.2,-111.4 -79.2,-111.3 -79.2,-111.3 -79.23,-111.3 -79.26,-111.3 -79.29,-111.3 -79.32,-111.3 -79.35,-111.3 -79.38,-111.3 -79.41,-111.3 -79.44,-111.3 -79.47,-111.3 -79.5,-111.4 -79.5,-111.5 -79.5,-111.6 -79.5,-111.7 -79.5,-111.8 -79.5,-111.9 -79.5,-112 -79.5,-112.1 -79.5,-112.2 -79.5,-112.3 -79.5,-112.3 -79.47,-112.3 -79.44,-112.3 -79.41,-112.3 -79.38,-112.3 -79.35,-112.3 -79.32,-112.3 -79.29,-112.3 -79.26,-112.3 -79.23,-112.3 -79.2))", "dataset_titles": "ApRES Firn Density Study; ApRES Vertical Strain Study; GPS Horizontal Strain Network; South Pole (SPICEcore) Borehole Deformation; WAIS Divide Borehole Deformation", "datasets": [{"dataset_uid": "200141", "doi": "", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "GPS Horizontal Strain Network", "url": ""}, {"dataset_uid": "601315", "doi": "10.15784/601315", "keywords": "Acoustic Televiewer; Anisotropy; Antarctica; Borehole Logging; Cryosphere; Deformation; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Flow; Snow/Ice; South Pole; SPICEcore", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole (SPICEcore) Borehole Deformation", "url": "https://www.usap-dc.org/view/dataset/601315"}, {"dataset_uid": "601314", "doi": "10.15784/601314", "keywords": "Acoustic Televiewer; Anisotropy; Antarctica; Borehole Logging; Cryosphere; Deformation; Glaciers/Ice Sheet; Glaciology; Ice Flow; WAIS divide; WAIS Divide Ice Core", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Borehole Deformation", "url": "https://www.usap-dc.org/view/dataset/601314"}, {"dataset_uid": "601322", "doi": "10.15784/601322", "keywords": "Antarctica; Cryosphere; Firn; Firn Density; Glaciology; Ice Penetrating Radar; Phase Sensitive Radar; Radar; Snow/Ice; WAIS divide", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "ApRES Firn Density Study", "url": "https://www.usap-dc.org/view/dataset/601322"}, {"dataset_uid": "601323", "doi": "10.15784/601323", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Penetrating Radar; Ice Strain; Phase Sensitive Radar; Radar; Snow/Ice; WAIS divide", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "ApRES Vertical Strain Study", "url": "https://www.usap-dc.org/view/dataset/601323"}], "date_created": "Fri, 15 May 2020 00:00:00 GMT", "description": "This award supports a project to develop a better understanding of the relation between ice microstructure, impurities, and ice flow and their connection to climate history for the West Antarctic Ice Sheet (WAIS) ice core site. This work builds on several ongoing studies at Siple Dome in West Antarctica and Dome C in East Antarctica. It is well known that the microstructure of ice evolves with depth and time in an ice sheet. This evolution of microstructure depends on the ice flow field, temperature, and impurity content. The ice flow field, in turn, depends on microstructure, leading to feedbacks that create layered variation in microstructure that relates to climate and flow history. The research proposed here focuses on developing a better understanding of: 1) how ice microstructure evolves with time and stress in an ice sheet and how that relates to impurity content, temperature, and strain rate; 2) how variations in ice microstructure and impurity content affect ice flow patterns near ice divides (on both small (1cm to 1m) and large (1m to 100km) scales); and 3) in what ways is the spatial variability of ice microstructure and its effect on ice flow important for interpretation of climate history in the WAIS Divide ice core. The study will integrate existing ice core and borehole data with a detailed study of ice microstructure using Electron Backscatter Diffraction (EBSD) techniques and measurements of borehole deformation through time using Acoustic Televiewers. This will be the first study to combine these two novel techniques for studying the relation between microstructure and deformation and it will build on other data being collected as part of other WAIS Divide borehole logging projects (e.g. sonic velocity, optical dust logging, temperature and other measurements on the ice core including fabric measurements from thin section analyses as well as studies of ice chemistry and stable isotopes. The intellectual merit of the work is that it will improve interpretation of ice core data (especially information on past accumulation) and overall understanding of ice flow. The broader impacts are that the work will ultimately contribute to a better interpretation of ice core records for both paleoclimate studies and for ice flow history, both of which connect to the broader questions of the role of ice in the climate system. The work will also advance the careers of two early-career female scientists, including one with a hearing impairment disability. This project will support a PhD student at the UAF and provide research and field experience for two or three undergraduates at Dartmouth. The PIs plan to include a teacher on their field team and collaborate with UAF\u0027s \"From STEM to STEAM\" toward enhancing the connection between art and science.", "east": -111.3, "geometry": "POINT(-111.8 -79.35)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; GLACIERS/ICE SHEETS; ICE CORE RECORDS; USAP-DC; GLACIER MOTION/ICE SHEET MOTION; Radar; WAIS divide", "locations": "WAIS divide", "north": -79.2, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Pettit, Erin; Obbard, Rachel", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "UNAVCO", "repositories": "UNAVCO; USAP-DC", "science_programs": "WAIS Divide Ice Core; SPICEcore", "south": -79.5, "title": "Collaborative Research: VeLveT Ice - eVoLution of Fabric and Texture in Ice at WAIS Divide, West Antarctica", "uid": "p0010098", "west": -112.3}, {"awards": "1341464 Robinson, Rebecca; 1341432 Brzezinski, Mark", "bounds_geometry": "POLYGON((-175 -54,-174 -54,-173 -54,-172 -54,-171 -54,-170 -54,-169 -54,-168 -54,-167 -54,-166 -54,-165 -54,-165 -55.3,-165 -56.6,-165 -57.9,-165 -59.2,-165 -60.5,-165 -61.8,-165 -63.1,-165 -64.4,-165 -65.7,-165 -67,-166 -67,-167 -67,-168 -67,-169 -67,-170 -67,-171 -67,-172 -67,-173 -67,-174 -67,-175 -67,-175 -65.7,-175 -64.4,-175 -63.1,-175 -61.8,-175 -60.5,-175 -59.2,-175 -57.9,-175 -56.6,-175 -55.3,-175 -54))", "dataset_titles": "Diatom assemblage counts from NBP17-02 shipboard carboy experiments; Dissolved nutrient profiles from along 170\u00b0W between 67 and 54\u00b0S; Expedition Data of NBP1702; Particle composition measurements from along 170\u00b0W between 67-54\u00b0S; Particulate silicon and nitrogen concentrations and isotopic composition measurements in McLane pump profiles from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean; Silicon concentration and isotopic composition measurements in pore waters and sediments from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean; Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy", "datasets": [{"dataset_uid": "601276", "doi": "10.15784/601276", "keywords": "Antarctica; Biogenic Silica; Cryosphere; Nitrogen Isotopes; Southern Ocean", "people": "Robinson, Rebecca; Brzezinski, Mark", "repository": "USAP-DC", "science_program": null, "title": "Particle composition measurements from along 170\u00b0W between 67-54\u00b0S", "url": "https://www.usap-dc.org/view/dataset/601276"}, {"dataset_uid": "601576", "doi": "10.15784/601576", "keywords": "Antarctica; Biogenic Silica; Chemistry:Sediment; Cryosphere; Diatom; Diatom Bound; Lithogenic Silica; Marine Geoscience; NBP1702; Nitrogen Isotopes; Nitrogen Stable Isotope; Silicon Cycle; Silicon Stable Isotope; Southern Ocean", "people": "Brzezinski, Mark; Robinson, Rebecca; Closset, Ivia; Jones, Janice L.", "repository": "USAP-DC", "science_program": null, "title": " Particulate silicon and nitrogen concentrations and isotopic composition measurements in McLane pump profiles from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/601576"}, {"dataset_uid": "601562", "doi": "10.15784/601562", "keywords": "Antarctica; Biogenic Silica; Chemistry:Sediment; Cryosphere; Lithogenic Silica; Marine Geoscience; NBP1702; Pore Water Biogeochemistry; Sediments; Silicon Cycle; Silicon Stable Isotope; Southern Ocean", "people": "Closset, Ivia; Jones, Janice L.; Brzezinski, Mark", "repository": "USAP-DC", "science_program": null, "title": "Silicon concentration and isotopic composition measurements in pore waters and sediments from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/601562"}, {"dataset_uid": "601523", "doi": "10.15784/601523", "keywords": "Antarctica; Biology; Carboy Growouts; Cryosphere; Diatom; Diatom Assemblage Data; NBP1702; Oceans; R/V Nathaniel B. Palmer; Southern Ocean; Southern Ocean Summer", "people": "Robinson, Rebecca; Robinson, Rebecca ; Jones, Colin; Riesselman, Christina", "repository": "USAP-DC", "science_program": null, "title": "Diatom assemblage counts from NBP17-02 shipboard carboy experiments", "url": "https://www.usap-dc.org/view/dataset/601523"}, {"dataset_uid": "601522", "doi": "10.15784/601522", "keywords": "Antarctica; Cryosphere; Nitrogen Isotopes; Oceans; Paleoproxies; Southern Ocean", "people": "Robinson, Rebecca; Brzezinski, Mark; Riesselman, Christina; Robinson, Rebecca ; Kelly, Roger; Closset, Ivia; Jones, Colin", "repository": "USAP-DC", "science_program": null, "title": "Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy", "url": "https://www.usap-dc.org/view/dataset/601522"}, {"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": "601269", "doi": "10.15784/601269", "keywords": "Antarctica; Chlorophyll; Cryosphere; Southern Ocean", "people": "Brzezinski, Mark; Robinson, Rebecca", "repository": "USAP-DC", "science_program": null, "title": "Dissolved nutrient profiles from along 170\u00b0W between 67 and 54\u00b0S", "url": "https://www.usap-dc.org/view/dataset/601269"}], "date_created": "Wed, 26 Feb 2020 00:00:00 GMT", "description": "The rise in atmospheric carbon dioxide concentrations and associated climate changes make understanding the role of the ocean in large scale carbon cycle a priority. Geologic samples allow exploration of potential mechanisms for carbon dioxide drawdown during glacial periods through the use of geochemical proxies. Nitrogen and silicon isotope signatures from fossil diatoms (microscopic plants) are used to investigate changes in the physical supply and biological demand for nutrients (like nitrogen and silicon and carbon) in the Southern Ocean. The project will evaluate the use the nitrogen and silicon isotope proxies through a series of laboratory experiments and Southern Ocean field sampling. The results will provide quantification of real relationships between nitrogen and silicon isotopes and nutrient usage in the Southern Ocean and allow exploration of the role of other factors, including biological diversity, ice cover, and mixing, in altering the chemical signatures recorded by diatoms. Seafloor sediment samples will be used to evaluate how well the signal created in the water column is recorded by fossil diatoms buried in the seafloor. Improving the nutrient isotope proxies will allow for a more quantitative understanding of the role of polar biology in regulating natural variation in atmospheric carbon dioxide. The project will also result in the training of a graduate student and development of outreach materials targeting a broad popular audience.\r\n\r\nThis project seeks to test the fidelity of the diatom nitrogen and silicon isotope proxies, two commonly used paleoceanographic tools for investigating the role of the Southern Ocean biological pump in regulating atmospheric CO2 concentrations on glacial-interglacial timescales. Existing ground-truthing data, including culture experiments, surface sediment data and downcore reconstructions, all suggest that nutrient utilization is the primary driver of isotopic variation in the Southern Ocean. However, strong contribution of interspecific variation is implied by recent culture results. Moreover, field and laboratory studies present some contradictory results in terms of the relative importance of interspecific variation and of inferred post-depositional alteration of the nutrient isotope signals. Here, a first order test of the N and Si diatom nutrient isotope paleo-proxies, involving water column dissolved and particulate sampling and laboratory culturing of field-isolates, is proposed. Southern Ocean water, biomass, live diatoms and fossil diatom sampling will be conducted to investigate species and assemblage related variability in diatom nitrogen and silicon isotopes and their relationship to surface nutrient fields and early diagenesis. Access to fresh materials produced in an analogous environmental context to the sediments of primary interest is critical for making robust paleoceanographic reconstructions. Field sampling will occur along 175\u00b0W, transecting the Antarctic Circumpolar Current from the subtropics to the marginal ice edge. Collection of water, sinking/suspended particles and multi-core samples from 13 stations and 3 shipboard incubation experiments will be used to test four proposed hypotheses that together evaluate the significance of existing culture results and seek to allow the best use of diatom nutrient isotope proxies in evaluating the biological pump.", "east": -165.0, "geometry": "POINT(-170 -60.5)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; AMD; NITROGEN ISOTOPES; R/V NBP; AMD/US; NSF/USA; NUTRIENTS; USAP-DC", "locations": "Southern Ocean", "north": -54.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Robinson, Rebecca; Brzezinski, Mark", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -67.0, "title": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump", "uid": "p0010083", "west": -175.0}, {"awards": "1644027 Wallace, Paul; 1644020 Sims, Kenneth W.; 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; Cryosphere; 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": "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; Cryosphere; 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; Cryosphere; Ross Island; Sample/Collection Description; Sample Location", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Sample Locations Ross Island \u0026 Discovery Province", "url": "https://www.usap-dc.org/view/dataset/601504"}, {"dataset_uid": "601507", "doi": "10.15784/601507", "keywords": "Antarctica; Chemistry:Rock; Cryosphere; Geochemistry; Hydrogen; Ion Mass Spectrometry; Ross Island", "people": "Gaetani, Glenn", "repository": "USAP-DC", "science_program": null, "title": "G170 Secondary Ion Mass Spectrometry Analyses of Melt Inclusion Hydrogen Isotopes", "url": "https://www.usap-dc.org/view/dataset/601507"}, {"dataset_uid": "601506", "doi": "10.15784/601506", "keywords": "Antarctica; Cryosphere; 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"}], "date_created": "Sat, 08 Feb 2020 00:00:00 GMT", "description": "The depths at which magmas are stored, their pre-eruptive volatile contents, and the rates at which they ascend to the Earth\u0027s surface are important controls on the dynamics of volcanic eruptions. Basaltic magmas are likely to be vapor undersaturated as they begin their ascent from the mantle through the crust, but volatile solubility drops with decreasing pressure. Once vapor saturation is achieved and the magma begins to degas, its pre-eruptive volatile content is determined largely by the depth at which it resides within the crust. Magma stored in deeper reservoirs tend to experience less pre-eruptive degassing and to be richer in volatiles than magma shallower reservoirs. Eruptive style is influenced by the rate at which a magma ascends from the reservoir to the surface through its effect on the efficiency of vapor bubble nucleation, growth, and coalescence. The proposed work will advance our understanding of pre-eruptive storage conditions and syn-eruptive ascent rates through a combined field and analytical research program. Volatile measurements from olivine-hosted melt inclusions will be used to systematically investigate magma storage depths and ascent rates associated with alkaline volcanism in the Erebus volcanic province. A central goal of the project is to provide a spatial and temporal framework for interpreting results from studies of present-day volcanic processes at Mt Erebus volcano. The Erebus volcanic province of Antarctica is especially well suited to this type of investigation because: (1) there are many exposed mafic scoria cones, fissure vents, and hyaloclastites (exposed in sea cliffs) that produced rapidly quenched, olivine-rich tephra; (2) existing volatile data for Ross Island MIs show that magma storage was relatively deep compared to many mafic volcanic systems; (3) some of the eruptive centers ejected mantle xenoliths, allowing for comparison of ascent rates for xenolith-bearing and xenolith-free eruptions, and comparison of ascent rates for those bearing xenoliths with times estimated from settling velocities; and (4) the cold, dry conditions in Antarctica result in excellent tephra preservation compared to tropical and even many temperate localities. The project provides new tools for assessing volcanic hazards, facilitates collaboration involving researchers from three different institutions (WHOI, U Wyoming, and U Oregon), supports the researchers\u0027 involvement in teaching, advising, and outreach, and provides an educational opportunity for a promising young postdoctoral researcher. Understanding the interrelationships among magma volatile contents, reservoir depths, and ascent rates is vital for assessing volcanic hazards associated with alkaline volcanism across the globe.\r\n\r\n", "east": 169.6, "geometry": "POINT(166.85 -77.775)", "instruments": null, "is_usap_dc": true, "keywords": "Tephra; Turtle Rock; AMD/US; USA/NSF; 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": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "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": "1443437 Carlson, Anders; 1443268 Beard, Brian", "bounds_geometry": "POLYGON((-80 -65,-79 -65,-78 -65,-77 -65,-76 -65,-75 -65,-74 -65,-73 -65,-72 -65,-71 -65,-70 -65,-70 -65.5,-70 -66,-70 -66.5,-70 -67,-70 -67.5,-70 -68,-70 -68.5,-70 -69,-70 -69.5,-70 -70,-71 -70,-72 -70,-73 -70,-74 -70,-75 -70,-76 -70,-77 -70,-78 -70,-79 -70,-80 -70,-80 -69.5,-80 -69,-80 -68.5,-80 -68,-80 -67.5,-80 -67,-80 -66.5,-80 -66,-80 -65.5,-80 -65))", "dataset_titles": "Radiogenic isotopes of ODP Site 178-1096; Sand content of ODP Site 178-1096", "datasets": [{"dataset_uid": "200109", "doi": " doi:10.1594/PANGAEA.909411", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Sand content of ODP Site 178-1096", "url": "https://doi.pangaea.de/10.1594/PANGAEA.909411 "}, {"dataset_uid": "200108", "doi": " doi:10.1594/PANGAEA.909407 ", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Radiogenic isotopes of ODP Site 178-1096", "url": "https://doi.pangaea.de/10.1594/PANGAEA.909407"}], "date_created": "Fri, 31 Jan 2020 00:00:00 GMT", "description": "This project developed sediment provenance proxies to trace the sources of sediment discharged by the WAIS to the continental rise. The WAIS erodes sediments from various West Antarctic geologic terranes that are deposited in adjacent drift sites. The geochemistry and magnetic properties of drift sediments reflect the tectono-metamorphic history of their source terranes. Deglaciation of a terrane during WAIS collapse should be detectable by the loss of the terrane\u2019s geochemical and magnetic signature in continental-rise detrital sediments. Continental shelf late-Holocene sediments from near the current WAIS groundling line were analyzed for silt- and claysize Sr-Nd-Pb isotopes and major-trace elements. The suite of cores spans from the eastern Ross Sea to the northern tip of the Antarctic Peninsula and established the provenance signatures of the Ross and Amundsen Provinces of Marie Byrd Land, Pine Island Bay, Thurston Island/Eight Coast Block, Ellsworth-Whitmore Crustal Block, and Antarctic Peninsula terranes. Many of these terranes have similar tectono-metamorphic histories but Sr-Nd isotope data from detrital sediments suggest at least 3 distinct provenance signatures. This comprehensive grain-size-specific provenance data adds to on-going collection of glacial till mineral and bulk provenance data. An initial down core study of Ocean Drilling Program Site 1096 in the Bellingshausen Sea was used to assess the utility of these new grain-size-specific provenance proxies in documenting WAIS collapse. We found the presence of both the WAIS and APIS over the last 115,000 years, but absence of the WAIS before 115,000 years ago. This means that the WAIS was gone during the last interglacial period, an interval when sea level was at least 6 meters above present. ", "east": -70.0, "geometry": "POINT(-75 -67.5)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "West Antarctic Ice Sheet; GLACIERS/ICE SHEETS; West Antarctica; PALEOCLIMATE RECONSTRUCTIONS; NOT APPLICABLE; USAP-DC; ISOTOPES; GEOCHEMISTRY; Bellingshausen Sea", "locations": "West Antarctic Ice Sheet; West Antarctica; Bellingshausen Sea", "north": -65.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Anders, Carlson; Beard, Brian; Stoner, Joseph", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "PANGAEA", "repositories": "PANGAEA", "science_programs": null, "south": -70.0, "title": "Collaborative Research: Development of a Suite of Proxies to Detect Past Collapse of the West Antarctic Ice Sheet", "uid": "p0010079", "west": -80.0}, {"awards": "1443296 Cottle, John", "bounds_geometry": "POLYGON((-180 -76.85314,-179.4383642 -76.85314,-178.8767284 -76.85314,-178.3150926 -76.85314,-177.7534568 -76.85314,-177.191821 -76.85314,-176.6301852 -76.85314,-176.0685494 -76.85314,-175.5069136 -76.85314,-174.9452778 -76.85314,-174.383642 -76.85314,-174.383642 -77.658865,-174.383642 -78.46459,-174.383642 -79.270315,-174.383642 -80.07604,-174.383642 -80.881765,-174.383642 -81.68749,-174.383642 -82.493215,-174.383642 -83.29894,-174.383642 -84.104665,-174.383642 -84.91039,-174.9452778 -84.91039,-175.5069136 -84.91039,-176.0685494 -84.91039,-176.6301852 -84.91039,-177.191821 -84.91039,-177.7534568 -84.91039,-178.3150926 -84.91039,-178.8767284 -84.91039,-179.4383642 -84.91039,180 -84.91039,177.4459565 -84.91039,174.891913 -84.91039,172.3378695 -84.91039,169.783826 -84.91039,167.2297825 -84.91039,164.675739 -84.91039,162.1216955 -84.91039,159.567652 -84.91039,157.0136085 -84.91039,154.459565 -84.91039,154.459565 -84.104665,154.459565 -83.29894,154.459565 -82.493215,154.459565 -81.68749,154.459565 -80.881765,154.459565 -80.07604,154.459565 -79.270315,154.459565 -78.46459,154.459565 -77.658865,154.459565 -76.85314,157.0136085 -76.85314,159.567652 -76.85314,162.1216955 -76.85314,164.675739 -76.85314,167.2297825 -76.85314,169.783826 -76.85314,172.3378695 -76.85314,174.891913 -76.85314,177.4459565 -76.85314,-180 -76.85314))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 02 Dec 2019 00:00:00 GMT", "description": "Subduction takes place at convergent plate boundaries and involves sinking of one tectonic plate underneath another. Although this process is a key aspect of plate tectonics that shapes the planet over geologic time, and is a primary cause of earthquakes, it is not known what causes subduction to cease, and what effect it has on the deepest portions of the crust and the upper part of the mantle. By studying the age and composition of igneous rocks emplaced at the very end of the subduction cycle, this project seeks to understand what causes subduction to cease, and how this changes the composition and structure of the crust and upper mantle. Because this process occurs deep within the earth, the project will focus on rocks in the root of an ancient subduction zone, now exposed in the Transantarctic Mountains of Antarctica. In addition, Antarctica remains relatively poorly understood, and this project will contribute directly to increasing our understanding of the geologic history of this region. The project will focus on training graduate and undergraduate students - incorporating hands-on experience with an array of state-of-the-art analytical instrumentation. Students will also gain a range of more general skills including Geographic Information Systems (GIS), written and oral communication, and data management - strengths that are highly relevant to careers both in the academic and Geosciences industry. Each summer, high school students will be incorporated into aspects of the laboratory-based research through the UCSB research mentorship program. The PI and graduate students will engage the general public through a purpose-built iPhone App and multimedia website. Activities will include live phone and video conversations from the field between elementary school students and members of the team in Antarctica. \u003cbr/\u003e\u003cbr/\u003eThe mechanisms by which the deep crustal delaminates or \"founders\" and is returned to the mantle remains a fundamental problem in earth science. Specifically, little is known about the temporal and spatial scales over which this process occurs or the mechanisms that trigger such catastrophic events. Igneous rocks highly enriched in potassium, called lamprophyres, are often emplaced during, and immediately after, termination of subduction and therefore potentially provide direct insight into foundering. These enigmatic rocks are important because they represent near-primary mantle melt compositions and therefore their age, geochemistry and petrologic evolution reveal key information on both the composition of the upper mantle and its thermal state. Of equal importance, they reveal how these key parameters vary through both space and time. By evaluating lamprophyres along a subduction zone margin it is possible to extract: 1) local-scale information, such as the timing and duration of melting and the role of igneous crystallization processes in generation of isotopic heterogeneities; 2) along-strike variations in mantle source composition, temperature, and depth of melting 3) the plate-scale forces that control foundering and termination of subduction. This project will study a suite of lamprophyres along the axis of the Transantarctic Mountains, emplaced during the latest stages of the Neoproterozoic - Ordovician Ross orogeny, Antarctica (roughly 505 to 470 million years before present). High-precision geochronology (age determinations) will be combined with geochemical measurements on the rocks and minerals to understand the mechanisms and timing of deep crustal foundering/delamination.", "east": -174.383642, "geometry": "POINT(170.0379615 -80.881765)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "AGE DETERMINATIONS; ISOTOPES; PLATE TECTONICS; Antarctica; USAP-DC; NOT APPLICABLE", "locations": "Antarctica", "north": -76.85314, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Cottle, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repositories": null, "science_programs": null, "south": -84.91039, "title": "Petrologic Constraints on Subduction Termination From Lamprophyres, Ross Orogen, Antarctica", "uid": "p0010071", "west": 154.459565}, {"awards": "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 Sodium; SP19 Gas Chronology; Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "datasets": [{"dataset_uid": "601399", "doi": "10.15784/601399", "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/601399"}, {"dataset_uid": "601239", "doi": "10.15784/601239", "keywords": "Antarctica; Cavity Ring Down Spectrometers; Cryosphere; Delta 18O; Delta Deuterium; Deuterium Isotopes; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core; Ice Core Chemistry; Ice Core Data; Oxygen Isotopes; Snow/Ice; Stable Isotopes", "people": "Vaughn, Bruce; Jones, Tyler R.; Kahle, Emma; Morris, Valerie; Steig, Eric J.; White, James; Schauer, Andrew", "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": "601396", "doi": "10.15784/601396", "keywords": "Accumulation; Antarctica; Cryosphere; Diffusion Length; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Dynamics; Layer Thinning; Oxygen Isotopes; South Pole; SPICECORE; Temperature", "people": "Waddington, Edwin D.; Kahle, Emma; Steig, Eric J.; Jones, Tyler R.; Fudge, T. J.; Koutnik, Michelle; Morris, Valerie; Vaughn, Bruce; Schauer, Andrew; Stevens, Max; Conway, Howard; Buizert, Christo; Epifanio, Jenna; White, James", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "url": "https://www.usap-dc.org/view/dataset/601396"}, {"dataset_uid": "601475", "doi": "10.15784/601475", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; 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 Sodium", "url": "https://www.usap-dc.org/view/dataset/601475"}, {"dataset_uid": "601429", "doi": "10.15784/601429", "keywords": "Antarctica; Climate; Cryosphere; Deuterium; Glaciers/Ice Sheet; Glaciology; Hydrogen; Ice; Ice Core; Ice Core Chemistry; Oxygen; Paleoclimate; Snow/Ice; South Pole; Stable Isotopes", "people": "Morris, Valerie; Vaughn, Bruce; White, James; Jones, Tyler R.; Steig, Eric J.; Schauer, Andrew; Kahle, Emma", "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": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}], "date_created": "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.\u003cbr/\u003e\u003cbr/\u003eThis 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": "d18O; Oxygen Isotopes; LABORATORY; OXYGEN ISOTOPE ANALYSIS; South Pole; USAP-DC; GLACIERS/ICE SHEETS; Antarctica; SPICore; 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": "1141839 Steig, Eric; 1142646 Twickler, Mark; 1142517 Aydin, Murat", "bounds_geometry": "POINT(90 -90)", "dataset_titles": "South Pole Ice Core Holocene Major Ion Dataset; South Pole Ice Core Sea Salt Sodium; South Pole ice core (SPC14) discrete methane data; South Pole Ice Core (SPICEcore) SPC14 Core Quality Versus Depth; SP19 Gas Chronology; Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "datasets": [{"dataset_uid": "601475", "doi": "10.15784/601475", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; 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 Sodium", "url": "https://www.usap-dc.org/view/dataset/601475"}, {"dataset_uid": "601221", "doi": "10.15784/601221", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Data; Ice Core Depth; Ice Core Records; Snow/Ice; SPICEcore", "people": "Aydin, Murat; Nicewonger, Melinda R.; Fudge, T. J.; Hargreaves, Geoff; Nunn, Richard; Steig, Eric J.; Kahle, Emma; Casey, Kimberly A.; Fegyveresi, John; Twickler, Mark; Souney, Joseph Jr.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core (SPICEcore) SPC14 Core Quality Versus Depth", "url": "https://www.usap-dc.org/view/dataset/601221"}, {"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; CH4; Cryosphere; 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": "601381", "doi": "10.15784/601381", "keywords": "Antarctica; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Methane; South Pole; SPICEcore", "people": "Buizert, Christo; Brook, Edward J.; Epifanio, Jenna; Edwards, Jon S.; Sowers, Todd A.; Kahle, Emma; Steig, Eric J.; Winski, Dominic A.; Osterberg, Erich; Fudge, T. J.; Hood, Ekaterina; Kalk, Michael; Ferris, David G.; Kennedy, Joshua A.; Severinghaus, Jeffrey P.; Aydin, Murat; Kreutz, Karl", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}, {"dataset_uid": "601396", "doi": "10.15784/601396", "keywords": "Accumulation; Antarctica; Cryosphere; Diffusion Length; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Dynamics; Layer Thinning; Oxygen Isotopes; South Pole; SPICECORE; Temperature", "people": "Waddington, Edwin D.; Kahle, Emma; Steig, Eric J.; Jones, Tyler R.; Fudge, T. J.; Koutnik, Michelle; Morris, Valerie; Vaughn, Bruce; Schauer, Andrew; Stevens, Max; Conway, Howard; Buizert, Christo; Epifanio, Jenna; White, James", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "url": "https://www.usap-dc.org/view/dataset/601396"}, {"dataset_uid": "601399", "doi": "10.15784/601399", "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/601399"}], "date_created": "Wed, 30 Oct 2019 00:00:00 GMT", "description": "This proposal requests support for a project to drill and recover a new ice core from South Pole, Antarctica. The South Pole ice core will be drilled to a depth of 1500 m, providing an environmental record spanning approximately 40 kyrs. This core will be recovered using a new intermediate drill, which is under development by the U.S. Ice Drilling Design and Operations (IDDO) group in collaboration with Danish scientists. This proposal seeks support to provide: 1) scientific management and oversight for the South Pole ice core project, 2) personnel for ice core drilling and core processing, 3) data management, and 3) scientific coordination and communication via scientific workshops. The intellectual merit of the work is that the analysis of stable isotopes, atmospheric gases, and aerosol-borne chemicals in polar ice has provided unique information about the magnitude and timing of changes in climate and climate forcing through time. The international ice core research community has articulated the goal of developing spatial arrays of ice cores across Antarctica and Greenland, allowing the reconstruction of regional patterns of climate variability in order to provide greater insight into the mechanisms driving climate change. The broader impacts of the project include obtaining the South Pole ice core will support a wide range of ice core science projects, which will contribute to the societal need for a basic understanding of climate and the capability to predict climate and ice sheet stability on long time scales. Second, the project will help train the next generation of ice core scientists by providing the opportunity for hands-on field and core processing experience for graduate students and postdoctoral researchers. A postdoctoral researcher at the University of Washington will be directly supported by this project, and many other young scientists will interact with the project through individual science proposals. Third, the project will result in the development of a new intermediate drill which will become an important resource to US ice core science community. This drill will have a light logistical footprint which will enable a wide range of ice core projects to be carried out that are not currently feasible. Finally, although this project does not request funds for outreach activities, the project will run workshops that will encourage and enable proposals for coordinated outreach activities involving the South Pole ice core science team.", "east": 90.0, "geometry": "POINT(90 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "USAP-DC; Antarctica; ANALYTICAL LAB; USA/NSF; AMD; South Pole; ICE CORE RECORDS; FIELD INVESTIGATION; AMD/US; Ice Core", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Twickler, Mark; Souney, Joseph Jr.; Aydin, Murat; Steig, Eric J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: A 1500m Ice Core from South Pole", "uid": "p0010060", "west": 90.0}, {"awards": "1341728 Stone, John", "bounds_geometry": "POLYGON((-86.3 -81,-86.17 -81,-86.04 -81,-85.91 -81,-85.78 -81,-85.65 -81,-85.52 -81,-85.39 -81,-85.26 -81,-85.13 -81,-85 -81,-85 -81.03,-85 -81.06,-85 -81.09,-85 -81.12,-85 -81.15,-85 -81.18,-85 -81.21,-85 -81.24,-85 -81.27,-85 -81.3,-85.13 -81.3,-85.26 -81.3,-85.39 -81.3,-85.52 -81.3,-85.65 -81.3,-85.78 -81.3,-85.91 -81.3,-86.04 -81.3,-86.17 -81.3,-86.3 -81.3,-86.3 -81.27,-86.3 -81.24,-86.3 -81.21,-86.3 -81.18,-86.3 -81.15,-86.3 -81.12,-86.3 -81.09,-86.3 -81.06,-86.3 -81.03,-86.3 -81))", "dataset_titles": "Cosmogenic nuclide data, Harter Nunatak; Cosmogenic nuclide data, John Nunatak; Cosmogenic nuclide data, Mt Axtell; Cosmogenic nuclide data, Mt Goodwin; Cosmogenic nuclide data, Mt Tidd; Cosmogenic nuclide data, Mt Turcotte; Pirrit Hills subglacial bedrock core RB-2, cosmogenic Be-10, Al-26 data", "datasets": [{"dataset_uid": "200078", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, Mt Goodwin", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200076", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, Mt Tidd", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200075", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, Mt Axtell", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200079", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, Harter Nunatak", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200077", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, Mt Turcotte", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200080", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, John Nunatak", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "601214", "doi": "10.15784/601214", "keywords": "Aluminum-26; Antarctica; Be-10; Bedrock Core; Beryllium-10; Chemistry:Rock; Cosmogenic; Cosmogenic Dating; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; isotope data; Pirrit Hills; Rocks; Solid Earth; Subglacial Bedrock", "people": "Stone, John", "repository": "USAP-DC", "science_program": null, "title": "Pirrit Hills subglacial bedrock core RB-2, cosmogenic Be-10, Al-26 data", "url": "https://www.usap-dc.org/view/dataset/601214"}], "date_created": "Tue, 08 Oct 2019 00:00:00 GMT", "description": "This award supports a project to determine if the West Antarctic Ice Sheet (WAIS) has thinned and collapsed in the past few million years, and if so, when and how frequently this occurred. The principal aim is to identify climatic conditions or thresholds in the climate system that led to ice-sheet collapse in the past, and assess the threat of climate change to vulnerable ice sheets in the future. We recovered a subglacial bedrock core from beneath 150 m of ice cover in the Pirrit Hills, in West Antarctica, and measured cosmogenic nuclide profiles to determine the bedrock exposure history. Cosmic-ray-produced Be-10 and Al-26 in the core indicate: (i) Continuous Pleistocene ice cover averaging ~200 m; and (ii) One or more pre-Pleistocene deglaciations that exposed the core site for ~200-800 years in the Pliocene, or \u003e 800 years, in the Miocene. Optically stimulated luminescence (OSL) dating of the core top precludes exposure to sunlight since ~450 ka, consistent with the Be-10 and Al-26 data. Trapped atmospheric argon in ice recovered from 80 cm above the bedrock surface indicates an age for the enclosing ice \u003e 2 Ma (delta 40Ar/36Ar = -0.15 per-mil). Together, these results rule out any Pleistocene thinning of ice in the Pirrit Hills by more than 150 m.", "east": -85.0, "geometry": "POINT(-85.65 -81.15)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "DEPTH AT SPECIFIC AGES; USAP-DC; Antarctica; NOT APPLICABLE", "locations": "Antarctica", "north": -81.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Stone, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "ICE-D", "repositories": "ICE-D; USAP-DC", "science_programs": null, "south": -81.3, "title": "EXPROBE-WAIS: Exposed Rock Beneath the West Antarctic Ice Sheet, A Test for Interglacial Ice Sheet Collapse", "uid": "p0010057", "west": -86.3}, {"awards": "1443663 Cole-Dai, Jihong; 1443336 Osterberg, Erich; 1443397 Kreutz, Karl", "bounds_geometry": "POINT(-180 -90)", "dataset_titles": "Preliminary SPC14 high-resolution Fe and Mn biologically relevant and dissolved trace metal concentrations spanning -42 \u2013 54,300 years BP.; South Pole Ice Core Holocene Major Ion Dataset; South Pole Ice Core Sea Salt Sodium; South Pole ice core (SPC14) discrete methane data; South Pole (SPC14) microparticle concentration, mass concentration, flux, particle-size-distribution mode, and aspect ratio measurements; SPICEcore 400-480 m Major Ions SDSU; The South Pole Ice Core (SPICEcore) chronology and supporting data", "datasets": [{"dataset_uid": "601553", "doi": "10.15784/601553", "keywords": "Antarctica; Cryosphere; Dust; Ice Core; South Pole", "people": "Kreutz, Karl", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole (SPC14) microparticle concentration, mass concentration, flux, particle-size-distribution mode, and aspect ratio measurements", "url": "https://www.usap-dc.org/view/dataset/601553"}, {"dataset_uid": "601206", "doi": "10.15784/601206", "keywords": "Antarctica; Calcium (CA); Chemistry:Ice; Cryosphere; Depth; Glaciers/Ice Sheet; Glaciochemistry; Glaciology; Ice; Ice Core; Ice Core Chemistry; Ice Core Data; Ice Core Records; Ice Core Stratigraphy; Nitrate; Nitrogen Isotopes; Paleoclimate; Snow/Ice; South Pole; SPICEcore", "people": "Severinghaus, Jeffrey P.; Iverson, Nels; Jones, Tyler R.; Osterberg, Erich; Waddington, Edwin D.; Alley, Richard; Casey, Kimberly A.; Nicewonger, Melinda R.; Aydin, Murat; Ferris, David G.; Kahle, Emma; Morris, Valerie; Steig, Eric J.; Sowers, Todd A.; Beaudette, Ross; Brook, Edward J.; Ortman, Nikolas; Epifanio, Jenna; Kreutz, Karl; Cox, Thomas S.; Thundercloud, Zayta; Cole-Dai, Jihong; Fegyveresi, John; McConnell, Joseph; Sigl, Michael; Souney, Joseph Jr.; Bay, Ryan; Buizert, Christo; Dunbar, Nelia; Fudge, T. J.; Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "The South Pole Ice Core (SPICEcore) chronology and supporting data", "url": "https://www.usap-dc.org/view/dataset/601206"}, {"dataset_uid": "601381", "doi": "10.15784/601381", "keywords": "Antarctica; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Methane; South Pole; SPICEcore", "people": "Buizert, Christo; Brook, Edward J.; Epifanio, Jenna; Edwards, Jon S.; Sowers, Todd A.; Kahle, Emma; Steig, Eric J.; Winski, Dominic A.; Osterberg, Erich; Fudge, T. J.; Hood, Ekaterina; Kalk, Michael; Ferris, David G.; Kennedy, Joshua A.; Severinghaus, Jeffrey P.; Aydin, Murat; Kreutz, Karl", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}, {"dataset_uid": "601399", "doi": "10.15784/601399", "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/601399"}, {"dataset_uid": "601430", "doi": "10.15784/601430", "keywords": "Antarctica; Cryosphere; Ions; South Pole; SPICEcore", "people": "Cole-Dai, Jihong; Larrick, Carleigh", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SPICEcore 400-480 m Major Ions SDSU", "url": "https://www.usap-dc.org/view/dataset/601430"}, {"dataset_uid": "601475", "doi": "10.15784/601475", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; 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 Sodium", "url": "https://www.usap-dc.org/view/dataset/601475"}, {"dataset_uid": "601675", "doi": "10.15784/601675", "keywords": "Antarctica; Cryosphere; South Pole; SPICEcore", "people": "Kreutz, Karl", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Preliminary SPC14 high-resolution Fe and Mn biologically relevant and dissolved trace metal concentrations spanning -42 \u2013 54,300 years BP.", "url": "https://www.usap-dc.org/view/dataset/601675"}], "date_created": "Thu, 29 Aug 2019 00:00:00 GMT", "description": "This collaborative project explores the signatures and causes of natural climate change in the region surrounding Antarctica over the last 40,000 years as the Earth transitioned from an ice age into the modern warm period. The researchers will investigate how the wind belts that surround Antarctica changed in their strength and position through time, and document explosive volcanic eruptions and CO2 cycling in the Southern Ocean as potential climate forcing mechanisms over this interval. Understanding how and why the climate varied naturally in the past is critical for improving understanding of modern climate change and projections of future climate under higher levels of atmospheric CO2. \u003cbr/\u003e\u003cbr/\u003eThe investigators plan to conduct a suite of chemical measurements along the 1500m length of the South Pole Ice Core, including major ion and trace element concentrations, and microparticle (dust) concentrations and size distributions. These measurements will (1) extend the South Pole record of explosive volcanic eruptions to 40,000 years using sulfate and particle data; (2) establish the relative timing of climate changes in dust source regions of Patagonia, New Zealand, and Australia using dust flux data; (3) investigate changes in the strength and position of the westerly wind belt using dust size distribution data; and (4) quantify the flux of bioavailable trace metals deposited as dust to the Southern Ocean over time. These chemistry records will also be critical for creating the timescale that will be used by all researchers studying records from the South Pole core. The project will support four graduate students and several undergraduate students across three different institutions, and become a focus of the investigators\u0027 efforts to disseminate outcomes of climate change science to the broader community.", "east": -180.0, "geometry": "POINT(-180 -90)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; ICE CORE RECORDS; USAP-DC; USA/NSF; LABORATORY; AMD; AMD/US", "locations": "Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Osterberg, Erich", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements", "uid": "p0010051", "west": -180.0}, {"awards": "1826712 McMahon, Kelton; 1443386 Emslie, Steven; 1443424 McMahon, Kelton; 1443585 Polito, Michael", "bounds_geometry": "POLYGON((-180 -60,-166 -60,-152 -60,-138 -60,-124 -60,-110 -60,-96 -60,-82 -60,-68 -60,-54 -60,-40 -60,-40 -61.8,-40 -63.6,-40 -65.4,-40 -67.2,-40 -69,-40 -70.8,-40 -72.6,-40 -74.4,-40 -76.2,-40 -78,-54 -78,-68 -78,-82 -78,-96 -78,-110 -78,-124 -78,-138 -78,-152 -78,-166 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -76.2,160 -74.4,160 -72.6,160 -70.8,160 -69,160 -67.2,160 -65.4,160 -63.6,160 -61.8,160 -60,162 -60,164 -60,166 -60,168 -60,170 -60,172 -60,174 -60,176 -60,178 -60,-180 -60))", "dataset_titles": "Amino acid nitrogen isotope values of penguins from the Antarctic Peninsula region 1930s to 2010s; Ancient Adelie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica; Carbon and nitrogen stable isotope values of Antarctic Krill from the South Shetland Islands and the northern Antarctic Peninsula 2007 and 2009; Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula; Radiocarbon dating and stable isotope values of penguin and seal tissues recovered from ornithogenic soils on Platter Island, Danger Islands Archipelago, Antarctic Peninsula in December 2015.; Radioisotope dates and carbon (\u03b413C) and nitrogen (\u03b415N) stable isotope values from modern and mummified Ad\u00e9lie Penguin chick carcasses and tissue from the Ross Sea, Antarctica; Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.; Receding ice drove parallel expansions in Southern Ocean penguin; SNP data from \"Receding ice drove parallel expansions in Southern Ocean penguins\".; Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica; The rise and fall of an ancient Adelie penguin \u0027supercolony\u0027 at Cape Adare, Antarctica", "datasets": [{"dataset_uid": "601364", "doi": "10.15784/601364", "keywords": "Antarctica; Antarctic Peninsula; Arctocephalus gazella; Carbon; Cryosphere; Holocene; Nitrogen; Paleoecology; Penguin; Pygoscelis spp.; Stable Isotope Analysis; Weddell Sea", "people": "Polito, Michael; Herman, Rachael; Clucas, Gemma; Kalvakaalva, Rohit", "repository": "USAP-DC", "science_program": null, "title": "Radiocarbon dating and stable isotope values of penguin and seal tissues recovered from ornithogenic soils on Platter Island, Danger Islands Archipelago, Antarctic Peninsula in December 2015.", "url": "https://www.usap-dc.org/view/dataset/601364"}, {"dataset_uid": "200180", "doi": "", "keywords": null, "people": null, "repository": "NCBI BioProject", "science_program": null, "title": "Receding ice drove parallel expansions in Southern Ocean penguin", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA589336"}, {"dataset_uid": "200181", "doi": "10.6084/m9.figshare.c.4475300.v1", "keywords": null, "people": null, "repository": "Figshare", "science_program": null, "title": "SNP data from \"Receding ice drove parallel expansions in Southern Ocean penguins\".", "url": "https://doi.org/10.6084/m9.figshare.c.4475300.v1"}, {"dataset_uid": "601232", "doi": "10.15784/601232", "keywords": "Amino Acids; Antarctica; Antarctic Peninsula; Biology; Biosphere; Cryosphere; isotope data; Nitrogen Isotopes; Oceans; Penguins; Southern Ocean; Stable Isotope Analysis", "people": "Polito, Michael; McMahon, Kelton", "repository": "USAP-DC", "science_program": null, "title": "Amino acid nitrogen isotope values of penguins from the Antarctic Peninsula region 1930s to 2010s", "url": "https://www.usap-dc.org/view/dataset/601232"}, {"dataset_uid": "601263", "doi": "10.15784/601263", "keywords": "Abandoned Colonies; Antarctica; Cryosphere; Holocene; Penguin; Ross Sea; Stable Isotope Analysis", "people": "Kristan, Allyson; Patterson, William; Emslie, Steven", "repository": "USAP-DC", "science_program": null, "title": "Radioisotope dates and carbon (\u03b413C) and nitrogen (\u03b415N) stable isotope values from modern and mummified Ad\u00e9lie Penguin chick carcasses and tissue from the Ross Sea, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601263"}, {"dataset_uid": "601212", "doi": "10.15784/601212", "keywords": "Abandoned Colonies; Antarctica; Antarctic Peninsula; Cryosphere; Geochronology; Glaciers/Ice Sheet; Glaciology; Holocene; Holocene Beach Deposit; Penguin; Radiocarbon; Radiocarbon Dates; Snow/Ice; Stranger Point", "people": "Emslie, Steven", "repository": "USAP-DC", "science_program": null, "title": "Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601212"}, {"dataset_uid": "601210", "doi": "10.15784/601210", "keywords": "Antarctica; Antarctic Krill; Antarctic Peninsula; Biology; Biosphere; Carbon Isotopes; Cryosphere; isotope data; Krill; Nitrogen Isotopes; Oceans; Southern Ocean; Stable Isotope Analysis", "people": "Polito, Michael", "repository": "USAP-DC", "science_program": null, "title": "Carbon and nitrogen stable isotope values of Antarctic Krill from the South Shetland Islands and the northern Antarctic Peninsula 2007 and 2009", "url": "https://www.usap-dc.org/view/dataset/601210"}, {"dataset_uid": "601509", "doi": "10.15784/601509", "keywords": "Antarctica; Antarctic Fur Seal; Cryosphere; Elemental Concentrations; King Penguin; Population Dynamics; South Atlantic Ocean; South Georgia Island; Stable Isotope Analysis; Sub-Antarctic", "people": "Polito, Michael; Maiti, Kanchan; Kristan, Allyson; McMahon, Kelton", "repository": "USAP-DC", "science_program": null, "title": "Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.", "url": "https://www.usap-dc.org/view/dataset/601509"}, {"dataset_uid": "601382", "doi": "10.15784/601382", "keywords": "25 de Mayo/King George Island; Antarctica; Biology; Cryosphere; Delta 13C; Delta 15N; Dietary Shifts; Opportunistic Sampling; Penguins; Pygoscelis Penguins; Stranger Point", "people": "Ciriani, Yanina; Emslie, Steven", "repository": "USAP-DC", "science_program": null, "title": "Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica", "url": "https://www.usap-dc.org/view/dataset/601382"}, {"dataset_uid": "601374", "doi": "10.15784/601374", "keywords": "Adelie Penguin; Antarctica; Cape Irizar; Cryosphere; Drygalski Ice Tongue; Ross Sea; Stable Isotopes", "people": "Emslie, Steven", "repository": "USAP-DC", "science_program": null, "title": "Ancient Adelie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601374"}, {"dataset_uid": "601327", "doi": "10.15784/601327", "keywords": "Adelie Penguin; Antarctica; Biology; Biosphere; Cape Adare; Cryosphere; East Antarctica; Population Movement; Pygoscelis Adeliae; Radiocarbon; Ross Sea; Sea Level Rise; Stable Isotopes", "people": "Patterson, William; Emslie, Steven; McKenzie, Ashley", "repository": "USAP-DC", "science_program": null, "title": "The rise and fall of an ancient Adelie penguin \u0027supercolony\u0027 at Cape Adare, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601327"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "The Antarctic marine ecosystem is highly productive and supports a diverse range of ecologically and commercially important species. A key species in this ecosystem is Antarctic krill, which in addition to being commercially harvested, is the principle prey of a wide range of marine organisms including penguins, seals and whales. The aim of this study is to use penguins and other krill predators as sensitive indicators of past changes in the Antarctic marine food web resulting from climate variability and the historic harvesting of seals and whales by humans. Specifically this study will recover and analyze modern (\u003c20 year old), historic (20-200 year old) and ancient (200-10,000 year old) penguin and other krill predator tissues to track their past diets and population movements relative to shifts in climate and the availability of Antarctic krill. Understanding how krill predators were affected by these factors in the past will allow us to better understand how these predators, the krill they depend on, and the Antarctic marine ecosystem as a whole will respond to current challenges such as global climate change and an expanding commercial fishery for Antarctic krill. The project will further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. This project will support the cross-institutional training of undergraduate and graduate students in advanced analytical techniques in the fields of ecology and biogeochemistry. In addition, this project includes educational outreach aimed encouraging participation in science careers by engaging K-12 students in scientific issues related to Antarctica, penguins, marine ecology, biogeochemistry, and global climate change.\u003cbr/\u003e\u003cbr/\u003eThis research will help place recent ecological changes in the Southern Ocean into a larger historical context by examining decadal and millennial-scale shifts in the diets and population movements of Antarctic krill predators (penguins, seals, and squid) in concert with climate variability and commercial harvesting. This will be achieved by coupling advanced stable and radio isotope techniques, particularly compound-specific stable isotope analysis, with unprecedented access to modern, historical, and well-preserved paleo-archives of Antarctic predator tissues dating throughout the Holocene. This approach will allow the project to empirically test if observed shifts in Antarctic predator bulk tissue stable isotope values over the past millennia were caused by climate-driven shifts at the base of the food web in addition to, or rather than, shifts in predator diets due to a competitive release following the historic harvesting of krill eating whale and seals. In addition, this project will track the large-scale abandonment and reoccupation of penguin colonies around Antarctica in response to changes in climate and sea ice conditions over the past several millennia. These integrated field studies and laboratory analyses will provide new insights into the underlying mechanisms that influenced past shifts in the diets and population movements of charismatic krill predators such as penguins. This will allow for improved projections of the ecosystem consequences of future climate change and anthropogenic harvesting scenarios in the Antarctica that are likely to affect the availability of Antarctic krill.", "east": -40.0, "geometry": "POINT(-120 -69)", "instruments": null, "is_usap_dc": true, "keywords": "ANIMAL ECOLOGY AND BEHAVIOR; South Shetland Islands; AMD/US; Stable Isotopes; Polar; Ross Sea; USA/NSF; Weddell Sea; AMD; MARINE ECOSYSTEMS; USAP-DC; Penguins; Antarctica; PENGUINS; Southern Hemisphere; FIELD INVESTIGATION; Krill; MACROFOSSILS", "locations": "Southern Hemisphere; Ross Sea; South Shetland Islands; Weddell Sea; Polar; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Polito, Michael; Emslie, Steven; Kelton, McMahon; Patterson, William; McCarthy, Matthew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "Figshare; NCBI BioProject; USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "uid": "p0010047", "west": 160.0}, {"awards": "1401489 Sigman, Daniel", "bounds_geometry": "POLYGON((-180 -45,-144 -45,-108 -45,-72 -45,-36 -45,0 -45,36 -45,72 -45,108 -45,144 -45,180 -45,180 -47.5,180 -50,180 -52.5,180 -55,180 -57.5,180 -60,180 -62.5,180 -65,180 -67.5,180 -70,144 -70,108 -70,72 -70,36 -70,0 -70,-36 -70,-72 -70,-108 -70,-144 -70,-180 -70,-180 -67.5,-180 -65,-180 -62.5,-180 -60,-180 -57.5,-180 -55,-180 -52.5,-180 -50,-180 -47.5,-180 -45))", "dataset_titles": "Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age; Diatom-bound N isotope records over the last two glacial cycles in sediment core PS75/072-4.; Diatom-bound nitrogen isotope and opal flux records over the Holocene period in Southern Ocean sediment cores MD12-3396, MD11-3353 and PS75/072-4.; GOSHIP section IO8S and P18S", "datasets": [{"dataset_uid": "200050", "doi": "", "keywords": null, "people": null, "repository": "CLIVAR", "science_program": null, "title": "GOSHIP section IO8S and P18S", "url": "https://cchdo.ucsd.edu/"}, {"dataset_uid": "200051", "doi": "", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age", "url": "https://www.pnas.org/content/suppl/2017/03/14/1615718114.DCSupplemental"}, {"dataset_uid": "200048", "doi": "doi.pangaea.de/10.1594/PANGAEA.891436.", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Diatom-bound nitrogen isotope and opal flux records over the Holocene period in Southern Ocean sediment cores MD12-3396, MD11-3353 and PS75/072-4.", "url": "https://doi.pangaea.de/10.1594/PANGAEA.891436"}, {"dataset_uid": "200049", "doi": "doi.org/10.1594/PANGAEA.848271", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Diatom-bound N isotope records over the last two glacial cycles in sediment core PS75/072-4.", "url": "https://doi.org/10.1594/PANGAEA.848271"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "ABSTRACT\u003cbr/\u003eIntellectual Merit:\u003cbr/\u003eThe high concentration of the major nutrients nitrate and phosphate is a fundamental characteristic of the Antarctic Zone in the Southern Ocean and is central to its role in global ocean fertility and the global carbon cycle. The isotopic composition of diatom-bound organic nitrogen is one of the best hopes for reconstructing the nutrient status of polar surface waters over glacial cycles, which in turn may hold the explanation for the decline in atmospheric carbon dioxide during ice ages. The PIs propose to generate detailed diatom-bound nitrogen isotope (\u0026#948;15Ndb) records from high sedimentation rate cores from the Kerguelen Plateau. Because the cores were collected at relatively shallow seafloor depths, they have adequate planktonic and benthic foraminifera to develop accurate age models. The resulting data could be compared with climate records from Antarctic ice cores and other archives to investigate climate-related changes, including the major steps into and out of ice ages and the millennial-scale events that occur during ice ages and at their ends. The records generated in this project will provide a critical test of hypotheses for the cause of lower ice age CO2.\u003cbr/\u003e\u003cbr/\u003eBroader impacts:\u003cbr/\u003eThis study will contribute to the goal of understanding ice ages and past CO2 changes, which both have broad implications for future climate. Undergraduates will undertake summer internships, with the possibility of extending their work into junior year projects and senior theses. In addition, the PI will lead modules for two Princeton programs for middle school teachers and will host a teacher for a six-week summer research project.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; South Pacific Ocean; USAP-DC; NOT APPLICABLE", "locations": "South Pacific Ocean", "north": -45.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Sigman, Daniel", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "CLIVAR", "repositories": "CLIVAR; PANGAEA; Publication", "science_programs": null, "south": -70.0, "title": "High-resolution, Assemblage-specific Records of Diatom-bound N Isotopes from the Indian Sector of the Antarctic Ocean", "uid": "p0010046", "west": -180.0}, {"awards": "1443420 Dodd, Justin", "bounds_geometry": "POLYGON((167.07 -77.87,167.073 -77.87,167.076 -77.87,167.079 -77.87,167.082 -77.87,167.085 -77.87,167.088 -77.87,167.091 -77.87,167.094 -77.87,167.097 -77.87,167.1 -77.87,167.1 -77.873,167.1 -77.876,167.1 -77.879,167.1 -77.882,167.1 -77.885,167.1 -77.888,167.1 -77.891,167.1 -77.894,167.1 -77.897,167.1 -77.9,167.097 -77.9,167.094 -77.9,167.091 -77.9,167.088 -77.9,167.085 -77.9,167.082 -77.9,167.079 -77.9,167.076 -77.9,167.073 -77.9,167.07 -77.9,167.07 -77.897,167.07 -77.894,167.07 -77.891,167.07 -77.888,167.07 -77.885,167.07 -77.882,167.07 -77.879,167.07 -77.876,167.07 -77.873,167.07 -77.87))", "dataset_titles": "Diatom Oxygen Isotope Evidence of Pliocene (~4.68 to 3.44 Ma) Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "datasets": [{"dataset_uid": "601220", "doi": "10.15784/601220", "keywords": "AND-1B; ANDRILL; Antarctica; Chemistry:Sediment; Cryosphere; Delta 18O; Diatom; Mass Spectrometer; Oxygen Isotopes; Paleoclimate; Pliocene; Sediment; WAIS; West Antarctic Ice Sheet", "people": "Abbott, Tirzah; Dodd, Justin", "repository": "USAP-DC", "science_program": "ANDRILL", "title": "Diatom Oxygen Isotope Evidence of Pliocene (~4.68 to 3.44 Ma) Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "url": "https://www.usap-dc.org/view/dataset/601220"}], "date_created": "Tue, 06 Aug 2019 00:00:00 GMT", "description": "Abstract\u003cbr/\u003eDuring the Early Pliocene, 4.8 to 3.4 million years ago, warmer-than-present global temperatures resulted in a retreat of the Ross Ice Shelf and West Antarctic Ice Sheet. Understanding changes in ocean dynamics during times of reduced ice volume and increased temperatures in the geologic past will improve the predictive models for these conditions. The primary goal of the proposed research is to develop a new oxygen isotope record of Pliocene oceanographic conditions near the Antarctic continent. Oxygen isotope values from the carbonate tests of benthic foraminifera have become the global standard for paleo-oceanographic studies, but foraminifera are sparse in high-latitude sediment cores. This research will instead make use of oxygen isotope measurements from diatom silica preserved in a marine sediment core from the Ross Sea. The project is the first attempt at using this method and will advance understanding of global ocean dynamics and ice sheet-ocean interactions during the Pliocene. The project will foster the professional development of two early-career scientists and serve as training for graduate and undergraduate student researchers. The PIs will use this project to introduce High School students to polar/oceanographic research, as well as stable isotope geochemistry. Collaboration with teachers via NSTA and Polar Educators International will ensure the implementation of excellent STEM learning activities and curricula for younger students. \u003cbr/\u003e\u003cbr/\u003eTechnical Description\u003cbr/\u003eThis project will produce a high-resolution oxygen isotope record from well-dated diatom rich sediments that have been cross-correlated with global benthic foraminifera oxygen isotope records. Diatom silica frustules deposited during the Early Pliocene and recovered by the ANDRILL Project (AND-1B) provide ideal material for this objective. Diatomite unites in the AND-1B core are nearly pure, with little evidence of opal formation. A diatom oxygen isotope record from this core offers the potential to constrain lingering uncertainties about Ross Sea and Southern Ocean paleoceanography and Antarctic Ice Sheet history during a time of high atmospheric carbon dioxide concentrations. Specifically, oxygen isotope variations will be used to constrain changes in the water temperature and/or freshwater flux in the Pliocene Ross Sea. Diatom species data from the AND-1B core have been used to infer variations in the extent and duration of seasonal sea ice coverage, sea surface temperatures, and mid-water advection onto the continental shelf. However, the diatom oxygen isotope record will provide the first direct measure of water/oxygen isotope values at the Antarctic continental margin during the Pliocene.", "east": 167.1, "geometry": "POINT(167.085 -77.885)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "OXYGEN ISOTOPES; USAP-DC; Antarctica; NOT APPLICABLE", "locations": "Antarctica", "north": -77.87, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Dodd, Justin; Scherer, Reed Paul; Warnock, Jonathan", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -77.9, "title": "Diatom and Oxygen Isotope Evidence of Pliocene Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "uid": "p0010042", "west": 167.07}, {"awards": "1443550 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": "Polar Ice Cores 3,000 Year Nitrous Oxide d15N and d18O Data; SPICEcore Holocene CO2 and N2O data", "datasets": [{"dataset_uid": "200055", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Polar Ice Cores 3,000 Year Nitrous Oxide d15N and d18O Data", "url": "https://www.ncdc.noaa.gov/paleo-search/study/25530"}, {"dataset_uid": "601197", "doi": "10.15784/601197", "keywords": "Antarctica; Carbon Dioxide; Cryosphere; Ice Core Gas Records; Nitrous Oxide; South Pole; SPICEcore", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SPICEcore Holocene CO2 and N2O data", "url": "https://www.usap-dc.org/view/dataset/601197"}], "date_created": "Tue, 06 Aug 2019 00:00:00 GMT", "description": "The temperature of the earth is controlled, in part, by heat trapping gases that include carbon dioxide, methane, and nitrous oxide. Despite their importance to climate, direct measurements of these gases in the atmosphere are limited to the last 50 years at best. Air trapped in ice cores extends those data back hundreds of millennia, and measurements of greenhouse gases in ice cores underpin much of our understanding of global chemical cycles relevant to modern climate change. Existing records vary in quality and detail. The proposed work fills gaps in our knowledge of nitrous oxide and carbon dioxide over the last 10,000 years. New measurements from an ice core from the South Pole will be used to determine what role changes in ocean and land based processes played in controlling these gases, which decreased during the first 2,000 years of this time period, then gradually increased toward the present. The work will address a major controversy over whether early human activities could have impacted the atmosphere, and provide data to improve mathematical models of the land-ocean-atmosphere system that predict how future climate change will impact the composition of the atmosphere and climate. \u003cbr/\u003e\u003cbr/\u003eFor nitrous oxide the work will improve on existing concentration records It will also develop measurement of the isotopomers of nitrous oxide and explore their utility for understanding aspects of the Holocene nitrous oxide budget. The primary goal is to determine if marine and/or terrestrial emissions of nitrous oxide change in response to changes in Holocene climate. A new Holocene isotopic record for carbon dioxide (stable carbon and oxygen isotopes), will improve the precision of existing records by a factor 5 and increase the temporal resolution. These data will be used to evaluate controversial hypotheses about why carbon dioxide concentrations changed in the Holocene and provide insight into millennial scale processes in the carbon cycle, which are not resolved by current isotopic data. A graduate student and post doc will receive advanced training during and the student and principle investigator will conduct outreach efforts targeted at local middle school students. The proposed work will also contribute to teaching efforts by the PI and to public lectures on climate and climate change. The results will be disseminated through publications, data archive, and the OSU Ice Core Lab web site. New analytical methods of wide utility will also be developed and documented.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Antarctica; ICE CORE RECORDS; CARBON DIOXIDE; NOT APPLICABLE; USAP-DC; TRACE GASES/TRACE SPECIES; NITROUS OXIDE", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward J.", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "NCEI", "repositories": "NCEI; USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Controls on Variations in Atmospheric Carbon Dioxide and Nitrous Oxide During the Last 10,000 years", "uid": "p0010043", "west": -180.0}, {"awards": "1543267 Brook, Edward; 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": "601394", "doi": "10.15784/601394", "keywords": "Antarctica; Bruce Plateau; Cryosphere; 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": "Bereiter, Bernhard; Mosley-Thompson, Ellen; Buizert, Christo; Severinghaus, Jeffrey P.; Shackleton, Sarah; Mulvaney, Robert; Pyne, Rebecca L.; Etheridge, David; Bertler, Nancy; Brook, Edward J.; Baggenstos, Daniel", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Multi-site ice core Krypton stable isotope ratios", "url": "https://www.usap-dc.org/view/dataset/601394"}, {"dataset_uid": "601195", "doi": "10.15784/601195", "keywords": "Antarctica; Cryosphere; 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; Cryosphere; 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; Buizert, Christo; Baggenstos, Daniel; Severinghaus, Jeffrey P.; Pyne, Rebecca L.; Bertler, Nancy; Bereiter, Bernhard; Shackleton, Sarah; Mosley-Thompson, Ellen; Mulvaney, Robert; Brook, Edward J.", "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; Cryosphere; 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": "Bereiter, Bernhard; Buizert, Christo; Shackleton, Sarah; Severinghaus, Jeffrey P.; Brook, Edward J.; Baggenstos, Daniel; Etheridge, David; Bertler, Nancy; 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"}], "date_created": "Wed, 10 Jul 2019 00:00:00 GMT", "description": "Overview: The funded work investigated whether ice core 86Kr acts as a proxy for barometric pressure variability, and whether this proxy can be used in Antarctic ice cores to infer past movement of the Southern Hemisphere (SH) westerly winds. Pressure variations drive macroscopic air movement in the firn column, which reduces the gravitational isotopic enrichment of slow-diffusing gases (such as Kr). The 86Kr deviation from gravitational equilibrium (denoted D86Kr) thus reflects the magnitude of pressure variations (among other things). Atmospheric reanalysis data suggest that pressure variability over Antarctica is linked to the Southern Annular Mode (SAM) index and the position of the SH westerly winds. Preliminary data from the WAIS Divide ice core show a large excursion in D86Kr during the last deglaciation (20-9 ka before present). In this project the investigators (1) performed high-precision 86Kr analysis on ice core and firn air samples to establish whether D86Kr is linked to pressure variability; (2) Refined the deglacial WAIS Divide record of Kr isotopes; (3) Investigated the role of pressure variability in firn air transport using firn air models with firn microtomography data and Lattice- Boltzmann modeling; and (4) Investigated how barometric pressure variability in Antarctica is linked to the SAM index and the position/strength of the SH westerlies in past and present climates using GCM and reanalysis data. A key finding was that D86Kr in recent ice samples (e.g. last 50 years) from a broad spatial array of sites in Antarctica and Greenland showed a significant correlation with directly measured barometric pressure variability at the ice core site. This strongly supports the hypothesis that 86Kr can be used as a paleo-proxy for storminess.\r\nIntellectual Merit: The SH westerlies are a key component of the global climate system; they are an important control on the global oceanic overturning circulation and possibly on atmospheric CO2 concentrations. Poleward movement of the SH westerlies during the last deglaciation has been hypothesized, yet evidence from proxy and modeling studies remains inconclusive. The funded work could provide valuable new constraints on deglacial movement of the SH westerlies. This record can be compared to high-resolution CO2 data from the same core, allowing us to test hypotheses that link CO2 to the SH westerlies. Climate proxies are at the heart of paleoclimate research. The funded work has apparently led to the discovery of a completely new proxy, opening up exciting new research possibilities and increasing the scientific value of existing ice cores. Once validated, the 86Kr proxy could be applied to other time periods as well, providing a long-term perspective on the movement of the SH westerlies. The funded work has furthermore provided valuable new insights into firn air transport. \r\n\r\nBroader impact: The Southern Ocean is presently an important sink of atmospheric CO2, thereby reducing the warming associated with anthropogenic CO2 emissions. Stratospheric ozone depletion and greenhouse warming have displaced the SH westerlies poleward, with potential consequences for the future magnitude of this oceanic carbon uptake. The funded work may provide a paleo-perspective on past movement of the SH westerlies and its link to atmospheric CO2, which could guide projections of future oceanic CO2 uptake, with strong societal benefits. The awarded funds supported and trained an early-career postdoctoral scholar at OSU, and fostered (international) collaboration. Data from the study will be available to the scientific community and the broad public through recognized data centers. During this project the PI and senior personnel have continued their commitment to public outreach through media interviews and speaking to schools and the public about their work. The PI provides services to the community by chairing the IPICS (International Partnership in Ice Core Sciences) working group and organizing annual PIRE (Partnerships in International Research and Education) workshops.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "AMD/US; USA/NSF; FIRN; ICE CORE RECORDS; USAP-DC; Greenland; Xenon; Noble Gas; Ice Core; 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": "1543031 Ivany, Linda", "bounds_geometry": null, "dataset_titles": "NetCDF outputs from middle Eocene climate simulation using the GENESIS global circulation model ; Organic carbon isotope data from serially sampled Eocene driftwood from the La Meseta Fm., Seymour ; Oxygen isotope data from serially sampled Eocene bivalves from the La Meseta Fm., Seymour Island, Antarctica ", "datasets": [{"dataset_uid": "601174", "doi": "10.15784/601174", "keywords": "Antarctica; Biology; Biosphere; Bivalves; Cryosphere; Cucullaea; Eocene; Glaciers/Ice Sheet; isotope data; La Meseta Formation; Mass Spectrometer; Mass Spectrometry; Oxygen Isotopes; Paleotemperature; Paleotemperature; Retrotapes; Seasonality; Seymour Island", "people": "Judd, Emily", "repository": "USAP-DC", "science_program": null, "title": "Oxygen isotope data from serially sampled Eocene bivalves from the La Meseta Fm., Seymour Island, Antarctica ", "url": "https://www.usap-dc.org/view/dataset/601174"}, {"dataset_uid": "601173", "doi": "10.15784/601173 ", "keywords": "Antarctica; Carbon Isotopes; Cryosphere; Driftwood; Eocene; Geochemistry; Geochronology; isotope data; La Meseta Formation; Mass Spectrometer; Mass Spectrometry; Organic Carbon Isotopes; Seasonality; Seymour Island; Wood", "people": "Judd, Emily", "repository": "USAP-DC", "science_program": null, "title": "Organic carbon isotope data from serially sampled Eocene driftwood from the La Meseta Fm., Seymour ", "url": "https://www.usap-dc.org/view/dataset/601173"}, {"dataset_uid": "601175", "doi": "10.15784/601175 ", "keywords": "Antarctica; Atmosphere; Climate Model; Climate Model; Computer Model; Cryosphere; Eocene; Genesis; Global Circulation Model; Modeling; Model Output; Seasonality; Temperature", "people": "Judd, Emily", "repository": "USAP-DC", "science_program": null, "title": "NetCDF outputs from middle Eocene climate simulation using the GENESIS global circulation model ", "url": "https://www.usap-dc.org/view/dataset/601175"}], "date_created": "Tue, 23 Apr 2019 00:00:00 GMT", "description": "In order to understand what environmental conditions might look like for future generations, we need to turn to archives of past times when the world was indeed warmer, before anyone was around to commit them to collective memory. The geologic record of Earth\u0027s past offers a glimpse of what could be in store for the future. Research by Ivany and her team looks to Antarctica during a time of past global warmth to see how seasonality of temperature and rainfall in coastal settings are likely to change in the future. They will use the chemistry of fossils (a natural archive of these variables) to test a provocative hypothesis about near-monsoonal conditions in the high latitudes when the oceans are warm. If true, we can expect high-latitude shipping lanes to become more hazardous and fragile marine ecosystems adapted to constant cold temperatures to suffer. With growing information about how human activities are likely to affect the planet in the future, we will be able to make more informed decisions about policies today. This research involves an international team of scholars, including several women scientists, training of graduate students, and a public museum exhibit to educate children about how we study Earth\u0027s ancient climate and what we can learn from it.\u003cbr/\u003e\u003cbr/\u003eAntarctica is key to an understanding how Earth?s climate system works under conditions of elevated CO2. The poles are the most sensitive regions on the planet to climate change, and the equator-to-pole temperature gradient and the degree to which high-latitude warming is amplified are important components for climate models to capture. Accurate proxy data with good age control are therefore critical for testing numerical models and establishing global patterns. The La Meseta Formation on Seymour Island is the only documented marine section from the globally warm Eocene Epoch exposed in outcrop on the continent; hence its climate record is integral to studies of warming. Early data suggest the potential for strongly seasonal precipitation and runoff in coastal settings. This collaboration among paleontologists, geochemists, and climate modelers will test this using seasonally resolved del-18O data from fossil shallow marine bivalves to track the evolution of seasonality through the section, in combination with independent proxies for the composition of summer precipitation (leaf wax del-D) and local seawater (clumped isotopes). The impact of the anticipated salinity stratification on regional climate will be evaluated in the context of numerical climate model simulations. In addition to providing greater clarity on high-latitude conditions during this time of high CO2, the combination of proxy and model results will provide insights about how Eocene warmth may have been maintained and how subsequent cooling came about. As well, a new approach to the analysis of shell carbonates for 87Sr/86Sr will allow refinements in age control so as to allow correlation of this important section with other regions to clarify global climate gradients. The project outlined here will develop new and detailed paleoclimate records from existing samples using well-tuned as well as newer proxies applied here in novel ways. Seasonal extremes are climate parameters generally inaccessible to most studies but critical to an understanding of climate change; these are possible to resolve in this well-preserved, accretionary-macrofossil-bearing section. This is an integrated study that links marine and terrestrial climate records for a key region of the planet across the most significant climate transition in the Cenozoic.", "east": -56.0, "geometry": "POINT(-56.5 -64.25)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "PALEOCLIMATE RECONSTRUCTIONS; USAP-DC; ISOTOPES; NOT APPLICABLE; MACROFOSSILS; Antarctica", "locations": "Antarctica", "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Ivany, Linda; Lu, Zunli; Junium, Christopher; Samson, Scott", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.5, "title": "Seasonality, Summer Cooling, and Calibrating the Approach of the Icehouse in Late Eocene Antarctica", "uid": "p0010025", "west": -57.0}, {"awards": "1443710 Severinghaus, Jeffrey; 1443464 Sowers, Todd; 1443472 Brook, Edward", "bounds_geometry": "POINT(0 -90)", "dataset_titles": "South Pole CH4 data for termination; South Pole Ice Core Isotopes of N2 and Ar; South Pole ice core (SPC14) discrete methane data; South Pole ice core total air content; South Pole (SPICECORE) 15N, 18O, O2/N2 and Ar/N2; SP19 Gas Chronology", "datasets": [{"dataset_uid": "601230", "doi": "10.15784/601230", "keywords": "Antarctica; Atmospheric CH4; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Data; Methane; Methane Concentration; Snow/Ice; South Pole; SPICEcore", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole CH4 data for termination", "url": "https://www.usap-dc.org/view/dataset/601230"}, {"dataset_uid": "601381", "doi": "10.15784/601381", "keywords": "Antarctica; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Methane; South Pole; SPICEcore", "people": "Buizert, Christo; Brook, Edward J.; Epifanio, Jenna; Edwards, Jon S.; Sowers, Todd A.; Kahle, Emma; Steig, Eric J.; Winski, Dominic A.; Osterberg, Erich; Fudge, T. J.; Hood, Ekaterina; Kalk, Michael; Ferris, David G.; Kennedy, Joshua A.; Severinghaus, Jeffrey P.; Aydin, Murat; Kreutz, Karl", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}, {"dataset_uid": "601517", "doi": "10.15784/601517", "keywords": "Antarctica; Argon; Argon Isotopes; Cryosphere; Firn; Firn Temperature Gradient; Firn Thickness; Gas Isotopes; Gas Isotopes; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Nitrogen; Nitrogen Isotopes; South Pole; SPICEcore", "people": "Severinghaus, Jeffrey P.; Morgan, Jacob", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Isotopes of N2 and Ar", "url": "https://www.usap-dc.org/view/dataset/601517"}, {"dataset_uid": "601152", "doi": "10.15784/601152", "keywords": "Antarctica; Antarctic Ice Sheet; Chemistry:Gas; Chemistry:Ice; Cryosphere; Delta 18O; Dole Effect; Firn Thickness; Gas Isotopes; Geochemistry; Glaciers/Ice Sheet; Glaciology; Gravitational Settling; Ice; Ice Core Chemistry; Ice Core Data; Ice Core Gas Records; Ice Core Records; Inert Gases; Nitrogen; Nitrogen Isotopes; Oxygen; Oxygen Isotopes; Snow/Ice; South Pole; SPICECORE", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole (SPICECORE) 15N, 18O, O2/N2 and Ar/N2", "url": "https://www.usap-dc.org/view/dataset/601152"}, {"dataset_uid": "601231", "doi": "10.15784/601231", "keywords": "Air Content; Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Snow/Ice; South Pole; SPICEcore", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core total air content", "url": "https://www.usap-dc.org/view/dataset/601231"}, {"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}], "date_created": "Sat, 02 Feb 2019 00:00:00 GMT", "description": "Gases trapped in ice cores have revealed astonishing things about the greenhouse gas composition of the past atmosphere, including the fact that carbon dioxide concentrations never rose above 300 parts per million during the last 800,000 years. This places today\u0027s concentration of 400 parts per million in stark contrast. Furthermore, these gas records show that natural sources of greenhouse gas such as oceans and ecosystems act as amplifiers of climate change by increasing emissions of gases during warmer periods. Such amplification is expected to occur in the future, adding to the human-produced gas burden. The South Pole ice core will build upon these prior findings by expanding the suite of gases to include, for the first time, those potent trace gases that both trapped heat and depleted ozone during the past 40,000 years. The present project on inert gases and methane in the South Pole ice core will improve the dating of this crucial record, to unprecedented precision, so that the relative timing of events can be used to learn about the mechanism of trace gas production and destruction, and consequent climate change amplification. Ultimately, this information will inform predictions of future atmospheric chemical cleansing mechanisms and climate in the context of our rapidly changing atmosphere. This award also engages young people in the excitement of discovery and polar research, helping to entrain the next generations of scientists and educators. Education of graduate students, a young researcher (Buizert), and training of technicians, will add to the nation?s human resource base. \u003cbr/\u003e \u003cbr/\u003eThis award funds the construction of the gas chronology for the South Pole 1500m ice core, using measured inert gases (d15N and d40Ar--Nitrogen and Argon isotope ratios, respectively) and methane in combination with a next-generation firn densification model that treats the stochastic nature of air trapping and the role of impurities on densification. The project addresses fundamental gaps in scientific understanding that limit the accuracy of gas chronologies, specifically a poor knowledge of the controls on ice-core d15N and the possible role of layering and impurities in firn densification. These gaps will be addressed by studying the gas enclosure process in modern firn at the deep core site. The work will comprise the first-ever firn air pumping experiment that has tightly co-located measurements of firn structural properties on the core taken from the same borehole.\u003cbr/\u003e\u003cbr/\u003eThe project will test the hypothesis that the lock-in horizon as defined by firn air d15N, CO2, and methane is structurally controlled by impermeable layers, which are in turn created by high-impurity content horizons in which densification is enhanced. Thermal signals will be sought using the inert gas measurements, which improve the temperature record with benefits to the firn densification modeling. Neon, argon, and oxygen will be measured in firn air and a limited number of deep core samples to test whether glacial period layering was enhanced, which could explain low observed d15N in the last glacial period. Drawing on separate volcanic and methane synchronization to well-dated ice cores to create independent ice and gas tie points, independent empirical estimates of the gas age-ice age difference will be made to check the validity of the firn densification model-inert gas approach to calculating the gas age-ice age difference. These points will also be used to test whether the anomalously low d15N seen during the last glacial period in east Antarctic ice cores is due to deep air convection in the firn, or a missing impurity dependence in the firn densification models. \u003cbr/\u003e\u003cbr/\u003eThe increased physical understanding gained from these studies, combined with new high-precision measurements, will lead to improved accuracy of the gas chronology of the South Pole ice core, which will enhance the overall science return from this gas-oriented core. This will lead to clarification of timing of atmospheric gas variations and temperature, and aid in efforts to understand the biogeochemical feedbacks among trace gases. These feedbacks bear on the future response of the Earth System to anthropogenic forcing. Ozone-depleting substances will be measured in the South Pole ice core record, and a precise gas chronology will add value. Lastly, by seeking a better understanding of the physics of gas entrapment, the project aims to have an impact on ice-core science in general.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "AMD/US; USAP-DC; AMD; LABORATORY; Antarctica; NITROGEN ISOTOPES; USA/NSF; METHANE; FIELD INVESTIGATION", "locations": "Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.; Sowers, Todd A.; Brook, Edward J.", "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: Inert Gas and Methane Based Climate Records throughout the South Pole Deep Ice Core", "uid": "p0010005", "west": 0.0}, {"awards": "1443306 Mayewski, Paul; 1443263 Higgins, John", "bounds_geometry": null, "dataset_titles": "Carbon dioxide concentration and its stable carbon isotope composition in Allan Hills ice cores; Elemental and isotopic composition of heavy noble gases in Allan Hills ice cores; Elemental and isotopic composition of nitrogen, oxygen, and argon in Allan Hills ice cores; Greenhouse gas composition in the Allan Hills S27 ice core; Methane concentration in Allan Hills ice cores; Stable isotope composition of the trapped air in the Allan Hills S27 ice core; Stable water isotope data for the AH-1502 ice core drilled at the Allan Hills Blue ice area; Stable water isotope data for the AH-1503 ice core drilled at the Allan Hills Blue ice area; Stable water isotope data for the surface samples collected at the Allan Hills Blue ice area", "datasets": [{"dataset_uid": "601128", "doi": "10.15784/601128", "keywords": "Allan Hills; Antarctica; Blue Ice Area; Chemistry:Ice; Cryosphere; Delta 18O; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope record; Mass Spectrometry; Stable water isotopes", "people": "Kurbatov, Andrei V.; Mayewski, Paul A.; Yan, Yuzhen; Introne, Douglas", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable water isotope data for the AH-1503 ice core drilled at the Allan Hills Blue ice area", "url": "https://www.usap-dc.org/view/dataset/601128"}, {"dataset_uid": "601202", "doi": "10.15784/601202", "keywords": "Allan Hills; Allan Hills project; Antarctica; Carbon Dioxide; Carbon Isotopes; Chemistry:Ice; CO2; Cryosphere; Gas Chromatography; Glaciers/Ice Sheet; Glaciology; Greenhouse Gases; Ice; Ice Core Data; Ice Core Gas Records; Ice Core Records; Mass Spectrometer; Mass Spectrometry; Methane; Snow/Ice", "people": "Bender, Michael; Yan, Yuzhen; Higgins, John; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Carbon dioxide concentration and its stable carbon isotope composition in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601202"}, {"dataset_uid": "601130", "doi": "10.15784/601130", "keywords": "Allan Hills; Allan Hills project; Antarctica; Blue Ice Area; Chemistry:Ice; Cryosphere; Delta 18O; Delta Deuterium; Glaciers/Ice Sheet; Glaciology; Ice Core Gas Records; Ice Core Records; Oxygen; Snow/Ice; Stable water isotopes; Transantarctic Mountains", "people": "Yan, Yuzhen; Kurbatov, Andrei V.; Mayewski, Paul A.; Introne, Douglas", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable water isotope data for the surface samples collected at the Allan Hills Blue ice area", "url": "https://www.usap-dc.org/view/dataset/601130"}, {"dataset_uid": "601129", "doi": "10.15784/601129", "keywords": "Allan Hills; Allan Hills project; Antarctica; Blue Ice Area; Cryosphere; Delta 18O; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; isotope data; Oxygen; Snow/Ice; Stable water isotopes; Transantarctic Mountains", "people": "Introne, Douglas; Yan, Yuzhen; Kurbatov, Andrei V.; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable water isotope data for the AH-1502 ice core drilled at the Allan Hills Blue ice area", "url": "https://www.usap-dc.org/view/dataset/601129"}, {"dataset_uid": "601483", "doi": "10.15784/601483", "keywords": "AGDC-project; Allan Hills; Antarctica; Argon; Cryosphere; Ice; Ice Core Data; Ice Core Gas Records; Isotope; Mass Spectrometry; Nitrogen; Oxygen", "people": "Bender, Michael; Yan, Yuzhen; Higgins, John", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Elemental and isotopic composition of nitrogen, oxygen, and argon in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601483"}, {"dataset_uid": "601512", "doi": "10.15784/601512", "keywords": "Allan Hills; Antarctica; Blue Ice; Cryosphere; Ice Core; Ice Core Gas Records; Isotope; Nitrogen; Oxygen", "people": "Yan, Yuzhen; Higgins, John; Bender, Michael", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable isotope composition of the trapped air in the Allan Hills S27 ice core", "url": "https://www.usap-dc.org/view/dataset/601512"}, {"dataset_uid": "601201", "doi": "10.15784/601201", "keywords": "Allan Hills; Allan Hills project; Antarctica; Argon; Chemistry:Ice; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Data; Ice Core Gas Records; Krypton; Mass Spectrometer; Noble Gas; Snow/Ice; Xenon", "people": "Yan, Yuzhen; Higgins, John; Bender, Michael; Severinghaus, Jeffrey P.; Ng, Jessica", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Elemental and isotopic composition of heavy noble gases in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601201"}, {"dataset_uid": "601203", "doi": "10.15784/601203", "keywords": "Allan Hills; Allan Hills project; Antarctica; Chemistry:Ice; Cryosphere; Gas Chromatography; Glaciers/Ice Sheet; Glaciology; Greenhouse Gases; Ice; Ice Core Data; Ice Core Gas Records; Methane; Snow/Ice", "people": "Brook, Edward J.; Yan, Yuzhen; Higgins, John; Bender, Michael", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Methane concentration in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601203"}, {"dataset_uid": "601425", "doi": "10.15784/601425", "keywords": "Allan Hills; Antarctica; Blue Ice; Carbon Dioxide; Cryosphere; Ice Core; Methane", "people": "Brook, Edward J.; Yan, Yuzhen", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Greenhouse gas composition in the Allan Hills S27 ice core", "url": "https://www.usap-dc.org/view/dataset/601425"}], "date_created": "Thu, 18 Oct 2018 00:00:00 GMT", "description": "Bubbles of ancient air trapped in ice cores permit the direct reconstruction of atmospheric composition and allow us to link greenhouse gases and global climate over the last 800,000 years. Previous field expeditions to the Allan Hills blue ice area, Antarctica, have recovered ice cores that date to one million years, the oldest ice cores yet recovered from Antarctica. These records have revealed that interglacial CO2 concentrations decreased by 800,000 years ago and that, in the warmer world 1 million years ago, CO2 and Antarctic temperature were linked as during the last 800,000 years. This project will return to the Allan Hills blue ice area to recover additional ice cores that date to 1 million years or older. The climate records developed from the drilled ice cores will provide new insights into the chemical composition of the atmosphere and Antarctic climate during times of comparable or even greater warmth than the present day. Our results will help answer questions about issues associated with anthropogenic change. These include the relationship between temperature change and the mass balance of Antarctic ice; precipitation and aridity variations associated with radiatively forced climate change; and the climate significance of sea ice extent. The project will entrain two graduate students and a postdoctoral scholar, and will conduct outreach including workshops to engage teachers in carbon science and ice cores.\u003cbr/\u003e\u003cbr/\u003eBetween about 2.8-0.9 million years ago, Earth\u0027s climate was characterized by 40,000-year cycles, driven or paced by changes in the tilt of Earth\u0027s spin axis. Much is known about the \"40,000-year\" world from studies of deep-sea sediments, but our understanding of climate change during this period is incomplete because we lack records of Antarctic climate and direct records of atmospheric greenhouse gas concentrations. We propose to address these issues by building on our recent studies of ancient ice from the Main Ice Field, Allan Hills, Antarctica. During previous field seasons we recovered ice extending, discontinuously, from 0.1-1.0 million years old. Ice was dated by measuring the 40Ar/38Ar (Argon) ratio of the trapped gases. Our discovery of million year-old ice demonstrates that there is gas-record-quality ice from the 40,000-year world in the Allan Hills Main Ice Field. We have identified two different sites, each overlying bedrock at ~ 200 m depth, that are attractive targets for coring ice dating to 1 million years and older. This project aims to core the ice at these two sites, re-occupy a previous site with million year-old ice and drill it down to the bedrock, and generate 10-20 short (~10-meter) cores in areas where our previous work and terrestrial meteorite ages suggest ancient surface ice. We plan to date the ice using the 40Ar/38Ar ages of trapped Argon. We also plan to characterize the continuity of our cores by measuring the deuterium and oxygen isotope ratios in the ice, methane, ratios of Oxygen and Argon to Nitrogen in trapped gas, the Nitrogen-15 isotope (d15N) of Nitrogen, and the Oxygen-18 isotope (d18O) of Oxygen. As the ice may be stratigraphically disturbed, these measurements will provide diagnostic properties for assessing the continuity of the ice-core records. Successful retrieval of ice older than one million years will provide the opportunity for follow-up work to measure the CO2 concentration and other properties within the ice to inform on the temperature history of the Allan Hills region, dust sources and source-area aridity, moisture sources, densification conditions, global average ocean temperature, and greenhouse gas concentrations. We will analyze the data in the context of leading hypotheses of the 40,000-year world and the Mid-Pleistocene Transition to the 100,000-year world. We expect to advance understanding of climate dynamics during these periods.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "AMD; Allan Hills; ice cores; AMD/US; USA/NSF; FIELD INVESTIGATION; USAP-DC; LABORATORY", "locations": "Allan Hills", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Mayewski, Paul A.; Kurbatov, Andrei V.; Higgins, John; Bender, Michael", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": null, "title": "Collaborative Research: Window into the World with 40,000-year Glacial Cycles from Climate Records in Million Year-old Ice from the Allan Hills Blue Ice Area", "uid": "p0000760", "west": null}, {"awards": "1443471 Koutnik, Michelle; 1443341 Hawley, Robert", "bounds_geometry": "POLYGON((110 -89,117 -89,124 -89,131 -89,138 -89,145 -89,152 -89,159 -89,166 -89,173 -89,180 -89,180 -89.1,180 -89.2,180 -89.3,180 -89.4,180 -89.5,180 -89.6,180 -89.7,180 -89.8,180 -89.9,180 -90,173 -90,166 -90,159 -90,152 -90,145 -90,138 -90,131 -90,124 -90,117 -90,110 -90,110 -89.9,110 -89.8,110 -89.7,110 -89.6,110 -89.5,110 -89.4,110 -89.3,110 -89.2,110 -89.1,110 -89))", "dataset_titles": "7MHz radar in the vicinity of South Pole; Firn density and compaction rates 50km upstream of South Pole; Firn temperatures 50km upstream of South Pole; Shallow radar near South Pole; South Pole area GPS velocities; SPICEcore Advection", "datasets": [{"dataset_uid": "601266", "doi": "10.15784/601266", "keywords": "Antarctica; Cryosphere; Ice Core Data; South Pole; SPICECORE", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SPICEcore Advection", "url": "https://www.usap-dc.org/view/dataset/601266"}, {"dataset_uid": "601099", "doi": "10.15784/601099", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Radar; Snow Accumulation; Snow/Ice", "people": "Lilien, David; Waddington, Edwin D.; Conway, Howard; Koutnik, Michelle; Fudge, T. J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Shallow radar near South Pole", "url": "https://www.usap-dc.org/view/dataset/601099"}, {"dataset_uid": "601100", "doi": "10.15784/601100", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; GPS; Ice Velocity", "people": "Conway, Howard; Lilien, David; Koutnik, Michelle; Fudge, T. J.; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole area GPS velocities", "url": "https://www.usap-dc.org/view/dataset/601100"}, {"dataset_uid": "601369", "doi": "10.15784/601369", "keywords": "Antarctica; Cryosphere; Ice Sheet", "people": "Lilien, David; Waddington, Edwin D.; Koutnik, Michelle; Fudge, T. J.; Stevens, Max; Conway, Howard", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "7MHz radar in the vicinity of South Pole", "url": "https://www.usap-dc.org/view/dataset/601369"}, {"dataset_uid": "601525", "doi": "10.15784/601525", "keywords": "Antarctica; Cryosphere; Firn; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Snow/Ice; South Pole; SPICECORE; Temperature", "people": "Koutnik, Michelle; Fudge, T. J.; Conway, Howard; Lilien, David; Stevens, Christopher Max; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Firn temperatures 50km upstream of South Pole", "url": "https://www.usap-dc.org/view/dataset/601525"}, {"dataset_uid": "601680", "doi": "10.15784/601680", "keywords": "Antarctica; Cryosphere; Cryosphere; Firn; Glaciers/Ice Sheet; Glaciology; Snow/Ice; South Pole; temperatures", "people": "Fudge, T. J.; Waddington, Edwin D.; Conway, Howard; Lilien, David; Stevens, Christopher Max; Koutnik, Michelle", "repository": "USAP-DC", "science_program": null, "title": "Firn density and compaction rates 50km upstream of South Pole", "url": "https://www.usap-dc.org/view/dataset/601680"}], "date_created": "Thu, 14 Jun 2018 00:00:00 GMT", "description": "Ice-core records are critical to understanding past climate variations. An Antarctic ice core currently being drilled at the South Pole will allow detailed investigation of atmospheric gases and fill an important gap in understanding the pattern of climate variability across Antarctica. Critical to the interpretation of any ice core are: 1) accurate chronologies for both the ice and the trapped gas and 2) demonstration that records from the ice core reliably reflect climate. The proposed research will improve the ice and gas chronologies by making measurements of snow compaction in the upstream catchment in order to constrain age models of the ice. These measurements will be a key data set needed for better understanding and predicting time-varying conditions in the upper part of the ice sheet. The research team will measure the modern spatial gradients in accumulation rate, surface temperature, and water stable isotopes from shallow ice cores in the upstream catchment in order to determine the climate history from the ice-core record. The new ice-flow measurements will make it possible to define the path of ice from upstream to the South Pole ice-core drill site to assess spatial gradients in snowfall and to infer histories of snowfall from internal layers within the ice sheet. The project will be led by an early-career scientist, provide broad training to graduate students, and engage in public outreach on polar science.\u003cbr/\u003e\u003cbr/\u003eIce-core records of stable isotopes, aerosol-born particles, and atmospheric gases are critical to understanding past climate variations. The proposed research will improve the ice and gas chronologies in the South Pole ice core by making in situ measurements of firn compaction in the upstream catchment to constrain models of the gas-age ice-age difference. The firn measurements will be a key data set needed to form a constitutive relationship for firn, and will drive better understanding and prediction of transient firn evolution. The research team will measure the modern gradients in accumulation rate, surface temperature, and water stable isotopes in the upstream catchment to separate spatial (advection) variations from temporal (climate) variations in the ice-core records. The ice-flow measurements will define the flowline upstream of the drill site, assess spatial gradients in accumulation, and infer histories of accumulation from radar-observed internal layers. Results will directly enhance interpretation of South Pole ice-core records, and also advance understanding of firn densification and drive next-generation firn models.", "east": 180.0, "geometry": "POINT(145 -89.5)", "instruments": null, "is_usap_dc": true, "keywords": "FIRN; Firn; USAP-DC; South Pole; Radar; FIELD SURVEYS; ICE CORE RECORDS", "locations": "South Pole", "north": -89.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Koutnik, Michelle; Conway, Howard; Waddington, Edwin D.; Fudge, T. J.; Hawley, Robert L.; Osterberg, Erich", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: Characterization of Upstream Ice and Firn Dynamics affecting the South Pole Ice Core", "uid": "p0000200", "west": 110.0}, {"awards": "1443232 Waddington, Edwin", "bounds_geometry": "POLYGON((110 -89,117 -89,124 -89,131 -89,138 -89,145 -89,152 -89,159 -89,166 -89,173 -89,180 -89,180 -89.1,180 -89.2,180 -89.3,180 -89.4,180 -89.5,180 -89.6,180 -89.7,180 -89.8,180 -89.9,180 -90,173 -90,166 -90,159 -90,152 -90,145 -90,138 -90,131 -90,124 -90,117 -90,110 -90,110 -89.9,110 -89.8,110 -89.7,110 -89.6,110 -89.5,110 -89.4,110 -89.3,110 -89.2,110 -89.1,110 -89))", "dataset_titles": "AC-ECM for SPICEcore; ECM (DC and AC) multi-track data and images from 2016 processing season", "datasets": [{"dataset_uid": "601189", "doi": " 10.15784/601189 ", "keywords": "Antarctica; Cryosphere; Electrical Conductivity; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Physical Properties; Snow/Ice; South Pole; SPICEcore; Volcanic", "people": "Fudge, T. J.; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "AC-ECM for SPICEcore", "url": "https://www.usap-dc.org/view/dataset/601189"}, {"dataset_uid": "601366", "doi": "10.15784/601366", "keywords": "Antarctica; Cryosphere", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "ECM (DC and AC) multi-track data and images from 2016 processing season", "url": "https://www.usap-dc.org/view/dataset/601366"}], "date_created": "Tue, 08 May 2018 00:00:00 GMT", "description": "Ice cores record detailed histories of past climate variations. The South Pole ice core will allow investigation of atmospheric trace gases and fill an important gap in understanding the pattern of climate variability across Antarctica. An accurate timescale that assigns an age to the ice at each depth in the core is essential to interpretation of the ice-core records. This work will use electrical methods to identify volcanic eruptions throughout the past ~40,000 years in the core by detecting the enhanced electrical conductance in those layers due to volcanic impurities in the ice. These eruptions will be pattern-matched to other cores across Antarctica, synchronizing the timing of climate variations among cores and allowing the precise timescales developed for other Antarctic ice cores to be transferred to the South Pole ice core. The well-dated records of volcanic forcing will be combined with records of atmospheric gases, stable water-isotopes, and aerosols to better understand the large natural climate variations of the past 40,000 years. \u003cbr/\u003e \u003cbr/\u003eThe electrical conductance method and dielectric profiling measurements will be made along the length of each section of the South Pole ice core at the National Ice Core Lab. These measurements will help to establish a timescale for the core. Electrical measurements will provide a continuous record of volcanic events for the entire core including through the brittle ice (550-1250m representing ~10,000-20,000 year-old ice) where the core quality and thin annual layers may prevent continuous melt analysis and cause discrete measurements to miss volcanic events. The electrical measurements also produce a 2-D image of the electrical layering on a longitudinal cut surface of each core. These data will be used to identify any irregular or absent layering that would indicate a stratigraphic disturbance in the core. A robust chronology is essential to interpretation of the paleoclimate records from the South Pole ice core. The investigators will engage teachers through talks and webinars with the National Science Teachers Association and will share information with the public at events such as Polar Science Weekend at the Pacific Science Center. Results will be disseminated through publications and conference presentations and the data will be archived and publicly available.", "east": 180.0, "geometry": "POINT(145 -89.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; USA/NSF; AMD; AMD/US; LABORATORY", "locations": null, "north": -89.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fudge, T. J.; Waddington, Edwin D.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Using Electrical Conductance Measurements to Develop the South Pole Ice Core Chronology", "uid": "p0000378", "west": 110.0}, {"awards": "1142108 Koch, Paul", "bounds_geometry": "POLYGON((-180 -55.1,-168.1 -55.1,-156.2 -55.1,-144.3 -55.1,-132.4 -55.1,-120.5 -55.1,-108.6 -55.1,-96.7 -55.1,-84.8 -55.1,-72.9 -55.1,-61 -55.1,-61 -57.4,-61 -59.7,-61 -62,-61 -64.3,-61 -66.6,-61 -68.9,-61 -71.2,-61 -73.5,-61 -75.8,-61 -78.1,-72.9 -78.1,-84.8 -78.1,-96.7 -78.1,-108.6 -78.1,-120.5 -78.1,-132.4 -78.1,-144.3 -78.1,-156.2 -78.1,-168.1 -78.1,180 -78.1,178.47 -78.1,176.94 -78.1,175.41 -78.1,173.88 -78.1,172.35 -78.1,170.82 -78.1,169.29 -78.1,167.76 -78.1,166.23 -78.1,164.7 -78.1,164.7 -75.8,164.7 -73.5,164.7 -71.2,164.7 -68.9,164.7 -66.6,164.7 -64.3,164.7 -62,164.7 -59.7,164.7 -57.4,164.7 -55.1,166.23 -55.1,167.76 -55.1,169.29 -55.1,170.82 -55.1,172.35 -55.1,173.88 -55.1,175.41 -55.1,176.94 -55.1,178.47 -55.1,-180 -55.1))", "dataset_titles": "Southern Ocean Pinnipeds", "datasets": [{"dataset_uid": "000242", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Southern Ocean Pinnipeds", "url": "https://www.bco-dmo.org/project/726874"}], "date_created": "Wed, 28 Feb 2018 00:00:00 GMT", "description": "Building on previously funded NSF research, the use of paleobiological and paleogenetic data from mummified elephant seal carcasses found along the Dry Valleys and Victoria Land Coast in areas that today are too cold to support seal colonies (Mirougina leonina; southern elephant seals; SES) supports the former existence of these seals in this region. The occurrence and then subsequent disappearance of these SES colonies is consistent with major shifts in the Holocene climate to much colder conditions at the last ~1000 years BCE). \u003cbr/\u003e\u003cbr/\u003eFurther analysis of the preserved remains of three other abundant pinnipeds ? crabeater (Lobodon carciophagus), Weddell (Leptonychotes weddelli) and leopard (Hydrurga leptonyx) will be studied to track changes in their population size (revealed by DNA analysis) and their diet (studied via stable isotope analysis). Combined with known differences in life history, preferred ice habitat and ecosystem sensitivity among these species, this paleoclimate proxy data will be used to assess their exposure and sensitivity to climate change in the Ross Sea region during the past ~1-2,000 years", "east": -61.0, "geometry": "POINT(-128.15 -66.6)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; NOT APPLICABLE", "locations": null, "north": -55.1, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Koch, Paul; Costa, Daniel; Hoelzel, A. Rus", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -78.1, "title": "Collaborative Research: Exploring the Vulnerability of Southern Ocean Pinnipeds to Climate Change - An Integrated Approach", "uid": "p0000410", "west": 164.7}, {"awards": "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": "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"}, {"dataset_uid": "601336", "doi": "10.15784/601336", "keywords": "Antarctica; Carbon-14; Cryosphere; Larsen Ice Shelf; Lead-210; Marine Sediments; Radioisotope Analysis", "people": "DeMaster, David; Taylor, Richard", "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": "601319", "doi": "10.15784/601319", "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Bioturbation Coefficients; Diagenesis; Labile Organic Carbon (LOC); LOC Mean Residence Times; Marguerite Bay; Oceans; Organic Carbon Degradation Rates; Sediment Core", "people": "DeMaster, David; Taylor, Richard; Smith, Craig; Isla, Enrique; Thomas, Carrie", "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": "601304", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Box Corer; Cryosphere; 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"}], "date_created": "Sat, 03 Feb 2018 00:00:00 GMT", "description": "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.", "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; USAP-1341669; 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": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "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": "0732602 Truffer, Martin; 0732625 Leventer, Amy; 0732711 Smith, Craig; 0732651 Gordon, Arnold; 0732655 Mosley-Thompson, Ellen; 0732983 Vernet, Maria", "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": "601347", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Current Measurements; LADCP; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/V Nathaniel B. Palmer", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601347"}, {"dataset_uid": "601348", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/V Nathaniel B. Palmer; Salinity; Temperature", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": null, "title": "Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601348"}, {"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": "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": "600073", "doi": "10.15784/600073", "keywords": "Antarctica; Antarctic Peninsula; Araon1304; Biology; Biosphere; 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": "600167", "doi": "10.15784/600167", "keywords": "Antarctica; Antarctic Peninsula; Bruce Plateau; Cryosphere; Glaciology; Ice Core Records; Isotope; LARISSA; Paleoclimate; Sample/Collection Description; Snow Accumulation", "people": "Thompson, Lonnie G.; Mosley-Thompson, Ellen", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Bruce Plateau Accumulation O18 2009-1900", "url": "https://www.usap-dc.org/view/dataset/600167"}, {"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": "601211", "doi": "10.15784/601211", "keywords": "Antarctica; Antarctic Peninsula; Benthos; Biology; Cryosphere; 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": "601485", "doi": "10.15784/601485", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; 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": "601305", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Box Corer; Cryosphere; 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": "601306", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Box Corer; Cryosphere; 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": "601336", "doi": "10.15784/601336", "keywords": "Antarctica; Carbon-14; Cryosphere; Larsen Ice Shelf; Lead-210; Marine Sediments; Radioisotope Analysis", "people": "DeMaster, David; Taylor, Richard", "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": "601345", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1001; Oceans; Physical Oceanography; R/V Nathaniel B. Palmer; Salinity; Temperature", "people": "Huber, Bruce; Gordon, Arnold", "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": "601346", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; 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; cryospheric; Antarctica; Climate Change; LABORATORY; Climate Variability; multi-disciplinary; NBP1001; FIELD SURVEYS; Not provided; Antarctic Peninsula; R/V NBP; FIELD INVESTIGATION; AMD/US; USA/NSF; Ice Core; Holocene", "locations": "Antarctica; Antarctic Peninsula", "north": -57.8, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; 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": "Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "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": "1043471 Kaplan, Michael", "bounds_geometry": "POLYGON((-112.5 -79.468,-112.4586 -79.468,-112.4172 -79.468,-112.3758 -79.468,-112.3344 -79.468,-112.293 -79.468,-112.2516 -79.468,-112.2102 -79.468,-112.1688 -79.468,-112.1274 -79.468,-112.086 -79.468,-112.086 -79.4712,-112.086 -79.4744,-112.086 -79.4776,-112.086 -79.4808,-112.086 -79.484,-112.086 -79.4872,-112.086 -79.4904,-112.086 -79.4936,-112.086 -79.4968,-112.086 -79.5,-112.1274 -79.5,-112.1688 -79.5,-112.2102 -79.5,-112.2516 -79.5,-112.293 -79.5,-112.3344 -79.5,-112.3758 -79.5,-112.4172 -79.5,-112.4586 -79.5,-112.5 -79.5,-112.5 -79.4968,-112.5 -79.4936,-112.5 -79.4904,-112.5 -79.4872,-112.5 -79.484,-112.5 -79.4808,-112.5 -79.4776,-112.5 -79.4744,-112.5 -79.4712,-112.5 -79.468))", "dataset_titles": "List of samples of WAIS Divide and Byrd (deep) ice that were analyzed for radiogenic isotopes at LDEO", "datasets": [{"dataset_uid": "601065", "doi": "10.15784/601065", "keywords": "Antarctica; Cryosphere; Dust; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Sample/Collection Description; WAIS divide; WAIS Divide Ice Core", "people": "Kaplan, Michael", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "List of samples of WAIS Divide and Byrd (deep) ice that were analyzed for radiogenic isotopes at LDEO", "url": "https://www.usap-dc.org/view/dataset/601065"}], "date_created": "Sun, 29 Oct 2017 00:00:00 GMT", "description": "This award supports a project to obtain the first set of isotopic-based provenance data from the WAIS divide ice core. A lack of data from the WAIS prevents even a basic knowledge of whether different sources of dust blew around the Pacific and Atlantic sectors of the southern latitudes. Precise isotopic measurements on dust in the new WAIS ice divide core are specifically warranted because the data will be synergistically integrated with other high frequency proxies, such as dust concentration and flux, and carbon dioxide, for example. Higher resolution proxies will bridge gaps between our observations on the same well-dated, well-preserved core. The intellectual merit of the project is that the proposed analyses will contribute to the WAIS Divide Project science themes. Whether an active driver or passive recorder, dust is one of the most important but least understood components of regional and global climate. Collaborative and expert discussion with dust-climate modelers will lead to an important progression in understanding of dust and past atmospheric circulation patterns and climate around the southern latitudes, and help to exclude unlikely air trajectories to the ice sheets. The project will provide data to help evaluate models that simulate the dust patterns and cycle and the relative importance of changes in the sources, air trajectories and transport processes, and deposition to the ice sheet under different climate states. The results will be of broad interest to a range of disciplines beyond those directly associated with the WAIS ice core project, including the paleoceanography and dust- paleoclimatology communities. The broader impacts of the project include infrastructure and professional development, as the proposed research will initiate collaborations between LDEO and other WAIS scientists and modelers with expertise in climate and dust. Most of the researchers are still in the early phase of their careers and hence the project will facilitate long-term relationships. This includes a graduate student from UMaine, an undergraduate student from Columbia University who will be involved in lab work, in addition to a LDEO Postdoctoral scientist, and possibly an additional student involved in the international project PIRE-ICETRICS. The proposed research will broaden the scientific outlooks of three PIs, who come to Antarctic ice core science from a variety of other terrestrial and marine geology perspectives. Outreach activities include interaction with the science writers of the Columbia\u0027s Earth Institute for news releases and associated blog websites, public speaking, and involvement in an arts/science initiative between New York City\u0027s arts and science communities to bridge the gap between scientific knowledge and public perception.", "east": -112.086, "geometry": "POINT(-112.293 -79.484)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -79.468, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Kaplan, Michael; Winckler, Gisela; Goldstein, Steven L.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.5, "title": "A Study of Atmospheric Dust in the WAIS Divide Ice Core Based on Sr-Nd-Pb-He Isotopes", "uid": "p0000081", "west": -112.5}, {"awards": "1246378 Shevenell, Amelia", "bounds_geometry": "POLYGON((70 -68,70.5 -68,71 -68,71.5 -68,72 -68,72.5 -68,73 -68,73.5 -68,74 -68,74.5 -68,75 -68,75 -68.2,75 -68.4,75 -68.6,75 -68.8,75 -69,75 -69.2,75 -69.4,75 -69.6,75 -69.8,75 -70,74.5 -70,74 -70,73.5 -70,73 -70,72.5 -70,72 -70,71.5 -70,71 -70,70.5 -70,70 -70,70 -69.8,70 -69.6,70 -69.4,70 -69.2,70 -69,70 -68.8,70 -68.6,70 -68.4,70 -68.2,70 -68))", "dataset_titles": "Anvers Trough Foraminifer Stable Isotope data; Geochemical and sedimentologic data from NBP01-01 JPC-34", "datasets": [{"dataset_uid": "601064", "doi": "10.15784/601064", "keywords": "Antarctica; Antarctic Peninsula; Anvers Trough; Chemistry:Sediment; Cryosphere; Foraminifera; Geochemistry; Isotope; LMG1211; LMG1311; Marine Sediments; Oceans; Paleoclimate; Sample/Collection Description; Southern Ocean", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": null, "title": "Anvers Trough Foraminifer Stable Isotope data", "url": "https://www.usap-dc.org/view/dataset/601064"}, {"dataset_uid": "601180", "doi": "10.15784/601180", "keywords": "Antarctica; Be-10; Cryosphere; Glaciers/Ice Sheet; Grain Size; Late Quaternary; Magnetic Susceptibility; Mass Spectrometry; NBP0101; Paleoenvironments; Prydz Bay; Radiocarbon; R/V Nathaniel B. Palmer; Sediment; Sediment Core; Sediment Core Data", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": null, "title": "Geochemical and sedimentologic data from NBP01-01 JPC-34", "url": "https://www.usap-dc.org/view/dataset/601180"}], "date_created": "Fri, 27 Oct 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eSouthern Ocean processes play an important role in Late Quaternary glacial-interglacial climate change. However, the direct influence of newly upwelled warm nutrient-rich Circumpolar Deep Water on the Antarctic cryosphere remains speculative. The PI proposes to test the hypothesis that Circumpolar Deep Water-derived ocean heat negatively impacts the mass-balance of Antarctica?s ice sheets during deglaciations using precisely dated late Quaternary paleoceanographic studies of Antarctic margin sediments and a suite of geochemical proxies measured on three existing glacial marine sediment cores from the Prydz Channel, Antarctica. Specifically, the PI will use these data to reconstruct the Late Quaternary history of the Lambert Glacier/Amery Ice Shelf system; evaluate the timing, speed, and style of retreat of the Lambert Glacier/Amery Ice Shelf system during the last deglaciation, and to assess the impact of Circumpolar Deep Water intrusions on the Lambert Glacier/Amery Ice Shelf system in the Late Quaternary. Diatom bound radiocarbon and optically stimulated luminescence techniques will be used to obtain precise stratigraphic age control for the Prydz Channel siliceous muddy ooze intervals. In addition, the PI will measure sedimentary 10Be concentrations to determine the origin of the siliceous muddy ooze units and to track past changes in the position of the ice shelf front.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis proposal will support an early career female scientist and will provide professional development and research experiences for women/minority graduate and undergraduate students. The PI will take advantage of USF?s Oceanography Camp for Girls.", "east": 75.0, "geometry": "POINT(72.5 -69)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": true, "keywords": "R/V NBP; AMD/US; USAP-DC", "locations": null, "north": -68.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Shevenell, Amelia", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica", "uid": "p0000381", "west": 70.0}, {"awards": "1246378 Shevenell, Amelia", "bounds_geometry": "POLYGON((-65.32 -64.15,-65.309 -64.15,-65.298 -64.15,-65.287 -64.15,-65.276 -64.15,-65.265 -64.15,-65.254 -64.15,-65.243 -64.15,-65.232 -64.15,-65.221 -64.15,-65.21 -64.15,-65.21 -64.186,-65.21 -64.222,-65.21 -64.258,-65.21 -64.294,-65.21 -64.33,-65.21 -64.366,-65.21 -64.402,-65.21 -64.438,-65.21 -64.474,-65.21 -64.51,-65.221 -64.51,-65.232 -64.51,-65.243 -64.51,-65.254 -64.51,-65.265 -64.51,-65.276 -64.51,-65.287 -64.51,-65.298 -64.51,-65.309 -64.51,-65.32 -64.51,-65.32 -64.474,-65.32 -64.438,-65.32 -64.402,-65.32 -64.366,-65.32 -64.33,-65.32 -64.294,-65.32 -64.258,-65.32 -64.222,-65.32 -64.186,-65.32 -64.15))", "dataset_titles": "Anvers Trough Foraminifer Stable Isotope data; Geochemical and sedimentologic data from NBP01-01 JPC-34", "datasets": [{"dataset_uid": "601064", "doi": "10.15784/601064", "keywords": "Antarctica; Antarctic Peninsula; Anvers Trough; Chemistry:Sediment; Cryosphere; Foraminifera; Geochemistry; Isotope; LMG1211; LMG1311; Marine Sediments; Oceans; Paleoclimate; Sample/Collection Description; Southern Ocean", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": null, "title": "Anvers Trough Foraminifer Stable Isotope data", "url": "https://www.usap-dc.org/view/dataset/601064"}, {"dataset_uid": "601180", "doi": "10.15784/601180", "keywords": "Antarctica; Be-10; Cryosphere; Glaciers/Ice Sheet; Grain Size; Late Quaternary; Magnetic Susceptibility; Mass Spectrometry; NBP0101; Paleoenvironments; Prydz Bay; Radiocarbon; R/V Nathaniel B. Palmer; Sediment; Sediment Core; Sediment Core Data", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": null, "title": "Geochemical and sedimentologic data from NBP01-01 JPC-34", "url": "https://www.usap-dc.org/view/dataset/601180"}], "date_created": "Fri, 27 Oct 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eSouthern Ocean processes play an important role in Late Quaternary glacial-interglacial climate change. However, the direct influence of newly upwelled warm nutrient-rich Circumpolar Deep Water on the Antarctic cryosphere remains speculative. The PI proposes to test the hypothesis that Circumpolar Deep Water-derived ocean heat negatively impacts the mass-balance of Antarctica?s ice sheets during deglaciations using precisely dated late Quaternary paleoceanographic studies of Antarctic margin sediments and a suite of geochemical proxies measured on three existing glacial marine sediment cores from the Prydz Channel, Antarctica. Specifically, the PI will use these data to reconstruct the Late Quaternary history of the Lambert Glacier/Amery Ice Shelf system; evaluate the timing, speed, and style of retreat of the Lambert Glacier/Amery Ice Shelf system during the last deglaciation, and to assess the impact of Circumpolar Deep Water intrusions on the Lambert Glacier/Amery Ice Shelf system in the Late Quaternary. Diatom bound radiocarbon and optically stimulated luminescence techniques will be used to obtain precise stratigraphic age control for the Prydz Channel siliceous muddy ooze intervals. In addition, the PI will measure sedimentary 10Be concentrations to determine the origin of the siliceous muddy ooze units and to track past changes in the position of the ice shelf front.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis proposal will support an early career female scientist and will provide professional development and research experiences for women/minority graduate and undergraduate students. The PI will take advantage of USF?s Oceanography Camp for Girls.", "east": -65.21, "geometry": "POINT(-65.265 -64.33)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": true, "keywords": "R/V NBP; AMD/US; USAP-DC", "locations": null, "north": -64.15, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Shevenell, Amelia", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.51, "title": "Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica", "uid": "p0000381", "west": -65.32}, {"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; Cryosphere; 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": "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 1980s and early 1990s 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.\u003cbr\u003eTechnical Description of Project:\u003cbr\u003eThe 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": "1341390 Frank, Tracy", "bounds_geometry": null, "dataset_titles": "Stable carbon and oxygen isotope data from drill cores from McMurdo Sound, Antarctica", "datasets": [{"dataset_uid": "000195", "doi": "", "keywords": null, "people": null, "repository": "EarthChem", "science_program": null, "title": "Stable carbon and oxygen isotope data from drill cores from McMurdo Sound, Antarctica", "url": "http://dx.doi.org/10.1594/IEDA/100718"}], "date_created": "Fri, 06 Oct 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThis project will use sediment cores from the Victoria Land Basin (VLB), Antarctica, to study secondary (diagenetic) carbonate minerals, as indicators of the basin?s fluid-flow history, within the well-constrained tectonic, depositional, and climatic context provided by sediment cores. This study will provide insights into subsurface processes in Victoria Land Basin, Antarctica and their relationships with the region?s climatic, cryospheric, and tectonic history. The work will utilize cores previously recovered by US-sponsored stratigraphic drilling projects (CIROS, CRP, and ANDRILL projects). This work is motivated by the unexpected discovery of dense brine in the subsurface of Southern McMurdo Sound during drilling by the ANDRILL Southern McMurdo Sound project. The presence of the brine is intriguing because it contradicts previous models for the origin of subsurface fluids that called upon large contributions from glacial melt water. Project objectives involve documenting the distribution of the brine (and potentially other fluids) via characterization of diagenetic precipitates. The approach will involve integration of petrographic and geochemical data (including conventional carbon, oxygen, and ?clumped? isotopes) to fully characterize diagenetic phases and allow development of a robust paragenetic history. This work will provide novel insights into the Cenozoic evolution of the VLB and, more broadly, the role of glacial processes in generating subsurface fluids. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eResults from this project will help understand the origins of brines, groundwater and hydrocarbon reservoirs in analogous modern and ancient deposits elsewhere, which is of broad interest. This project will support the training of one graduate and one undergraduate student at the University of Nebraska-Lincoln (UNL) providing learning opportunities in sedimentary geology and diagenesis, fields with wide applicability. This proposal emphasizes rapid dissemination of results to the scientific community via conference presentations and contributions to peer-reviewed publications. The results will be integrated into education activities designed to develop skills in petrography and diagenesis, which are highly sought after in the energy sector. The project will generate a well-constrained dataset that allows direct linkage of diagenetic phases to environmental and tectonic change across a large sedimentary basin which will provide the basis for a comprehensive case study in an upper-level course (Sedimentary Petrography and Diagenesis) at UNL. In addition, online exercises will be developed and submitted to an open-access site (SEPM Stratigraphy Web) dedicated to sedimentary geology.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Instrumentation and Support", "paleo_time": null, "persons": "Frank, Tracy; Fielding, Christopher", "platforms": "Not provided", "repo": "EarthChem", "repositories": "EarthChem", "science_programs": null, "south": null, "title": "Insights into the Burial, Tectonic, and Hydrologic History of the Cenozoic Succession in McMurdo Sound, Antarctica through Analysis of Diagenetic Phases", "uid": "p0000256", "west": null}, {"awards": "1246190 Yu, Zicheng", "bounds_geometry": "POLYGON((-69 -64,-68.1 -64,-67.2 -64,-66.3 -64,-65.4 -64,-64.5 -64,-63.6 -64,-62.7 -64,-61.8 -64,-60.9 -64,-60 -64,-60 -64.4,-60 -64.8,-60 -65.2,-60 -65.6,-60 -66,-60 -66.4,-60 -66.8,-60 -67.2,-60 -67.6,-60 -68,-60.9 -68,-61.8 -68,-62.7 -68,-63.6 -68,-64.5 -68,-65.4 -68,-66.3 -68,-67.2 -68,-68.1 -68,-69 -68,-69 -67.6,-69 -67.2,-69 -66.8,-69 -66.4,-69 -66,-69 -65.6,-69 -65.2,-69 -64.8,-69 -64.4,-69 -64))", "dataset_titles": "Late Holocene paleoecological and paleoclimatic data from moss peatbanks in the western Antarctic Peninsula", "datasets": [{"dataset_uid": "601037", "doi": "10.15784/601037", "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Cryosphere; Moss; Paleoclimate; Sample/Collection Description", "people": "Yu, Zicheng", "repository": "USAP-DC", "science_program": null, "title": "Late Holocene paleoecological and paleoclimatic data from moss peatbanks in the western Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601037"}], "date_created": "Tue, 15 Aug 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThis research will investigate how Antarctic peatbanks have responded to documented past warm climates on the Western Antarctic Peninsula over the last 1000 years. The work will extend understanding of climate controls on peat carbon accumulation to Antarctic peatbanks thus enabling a bi-polar perspective of ?first responder? ecosystem processes under warmer climate conditions. Understanding climate and ecosystem histories will help reveal processes and mechanisms that control the functioning of these and other polar ecosystems. Specifically, the investigators will evaluate outcomes of ?natural climate-warming experiments? that have occurred in the AP region at 65 degrees south over the last 1000 years. They will focus on two warm climate intervals in the Western Antarctic Peninsula: (1) the recent and ongoing warming of up to 6\u00c2\u00b0C in the last century, and (2) the Medieval Warm Period that occurred ~800 years ago. By collecting and analyzing peat cores and other biological and environmental data, the investigators will derive an independent temperature reconstruction from oxygen isotopes of moss cellulose over the last 1000 years to assess peatbank carbon response to documented warm climate conditions. The overall goal of the proposed project is to document formation ages and temporal changes in carbon-accumulating ecosystems over the last millennium in response to climate change as reconstructed from independent proxies. Also, their data will allow the investigators to understand the nature of reconstructed climate change in relation to atmosphere circulation and ocean conditions. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis research is directly relevant to understanding polar processes affecting soil carbon dynamics and will support an early career researcher. This project will provide training for undergraduate students, graduate student and a postdoctoral fellow and will develop teaching modules and outreach activities on polar climate and ecosystem changes.", "east": -60.0, "geometry": "POINT(-64.5 -66)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Yu, Zicheng", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -68.0, "title": "Collaborative Research: Response of Carbon Accumulation in Moss Peatbanks to Past Warm Climates in the Antarctic Peninsula", "uid": "p0000341", "west": -69.0}, {"awards": "1246387 Guo, Weifu", "bounds_geometry": "POLYGON((-79.9183333 35.441666667,-55.16316667 35.441666667,-30.40800004 35.441666667,-5.65283341 35.441666667,19.10233322 35.441666667,43.85749985 35.441666667,68.61266648 35.441666667,93.36783311 35.441666667,118.12299974 35.441666667,142.87816637 35.441666667,167.633333 35.441666667,167.633333 25.9255333333,167.633333 16.4093999996,167.633333 6.8932666659,167.633333 -2.6228666678,167.633333 -12.1390000015,167.633333 -21.6551333352,167.633333 -31.1712666689,167.633333 -40.6874000026,167.633333 -50.2035333363,167.633333 -59.71966667,142.87816637 -59.71966667,118.12299974 -59.71966667,93.36783311 -59.71966667,68.61266648 -59.71966667,43.85749985 -59.71966667,19.10233322 -59.71966667,-5.65283341 -59.71966667,-30.40800004 -59.71966667,-55.16316667 -59.71966667,-79.9183333 -59.71966667,-79.9183333 -50.2035333363,-79.9183333 -40.6874000026,-79.9183333 -31.1712666689,-79.9183333 -21.6551333352,-79.9183333 -12.1390000015,-79.9183333 -2.6228666678,-79.9183333 6.8932666659,-79.9183333 16.4093999996,-79.9183333 25.9255333333,-79.9183333 35.441666667))", "dataset_titles": "Clumped isotope composition of modern cold water corals", "datasets": [{"dataset_uid": "000205", "doi": "", "keywords": null, "people": null, "repository": "EarthChem", "science_program": null, "title": "Clumped isotope composition of modern cold water corals", "url": "http://www.earthchem.org/"}], "date_created": "Fri, 07 Jul 2017 00:00:00 GMT", "description": "This proposed research aims to produce high resolution, precise and accurate records of deep water temperatures in the Drake Passage over the past ~40,000 years, by applying the newly developed carbonate clumped isotope thermometer to a unique collection of modern and fossil deep-sea corals, and thus advance the understanding of the role of the Southern Ocean in modulating global climate. In addition, this study will provide further evaluation on the potential of this new thermometer to derive accurate estimates of past ocean temperatures from deep-sea coral skeletons. Funding will support an early-career junior scientist and a graduate student. \u003cbr/\u003e\u003cbr/\u003eDespite its crucial role in modulating global climate, rates and amplitudes of environmental changes in the Southern Ocean are often difficult to constrain. In particular, the knowledge about the deep water temperatures in the Southern Ocean during the last glacial cycle is extremely limited. This results both from the lack of well-dated climate archives for the deep Southern Ocean and from the fact that most existing temperature proxies (e.g. del18O and Mg/Ca of foraminifera and corals) suffer from the biological \u0027vital effects\u0027. The latter is especially problematic; it causes substantial challenges in interpreting these geochemical proxies and can lead to biases equivalent to tens of degrees in temperature estimates. Recent development of carbonate clumped isotope thermometer, holds new promises for reconstructing deep water temperatures in the Southern Ocean, since calibration studies of this thermometer in deep-sea corals suggest it is largely free of vital effects. This proposed research seeks to refine the calibration of carbonate clumped isotope thermometer in deep-sea corals at low temperatures, improve the experimental methods to obtain high precision in temperature estimates, and then apply this thermometer to a unique collection of modern and fossil deep-sea corals collected from the Drake Passage during two recent Office of Polar Programs (OPP)-funded cruises, that have already been dated by radiocarbon and U-series methods. By combining the reconstructed temperatures with the radiocarbon and U-Th ages for these deep-sea corals, this study will explore the relationships between these temperature changes and global climate changes.", "east": 167.633333, "geometry": "POINT(43.85749985 -12.1390000015)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": 35.441666667, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Guo, Weifu", "platforms": "Not provided", "repo": "EarthChem", "repositories": "EarthChem", "science_programs": null, "south": -59.71966667, "title": "Reconstruction of Deep-Water Temperatures in the Drake Passage Over the Last Glacial Cycle: Application of Carbonate Clumped Isotope Thermometer to Absolutely-Dated Deep-Sea Corals", "uid": "p0000389", "west": -79.9183333}, {"awards": "1341360 Steig, Eric", "bounds_geometry": "POINT(106 -77.5)", "dataset_titles": "Seasonal 17O Isotope Data from Lake Vostok and WAIS Divide Snow Pits", "datasets": [{"dataset_uid": "601031", "doi": "10.15784/601031", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Lake Vostok; Snow Pit; WAIS Divide Ice Core", "people": "Steig, Eric J.; Schoenemann, Spruce", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Seasonal 17O Isotope Data from Lake Vostok and WAIS Divide Snow Pits", "url": "https://www.usap-dc.org/view/dataset/601031"}], "date_created": "Tue, 06 Jun 2017 00:00:00 GMT", "description": "Steig/1341360\u003cbr/\u003e\u003cbr/\u003eThis award supports a two-year project to develop a method for rapid and precise measurements of the difference in 18O/16O and 17O/16O isotope ratios in water, referred to as the 17O-excess. Measurement of 17O-excess is a recent innovation in geochemistry, complementing traditional measurements of the ratios of hydrogen (D/H) and oxygen (18O/16O). Conventional measurements of 17O/16O are limited in number because of the time-consuming and laborious nature of the analyses, which involves the conversion of water to oxygen via fluorination, followed by high-precision mass spectrometry. This project will use a novel cavity ring-down spectroscopy (CRDS) system developed by a joint effort of the University of Washington and Picarro, Inc. (Santa Clara, CA), along with the Centre for Ice and Climate (Neils Bohr Institute, Copenhagen). The primary intellectual merit of the research is the improvement of the CRDS method for measurements of 17Oexcess of discrete samples of water, to obtain precision and accuracy competitive with conventional methods using mass spectrometry. This will be achieved by quantification of the effects of water vapor concentration variability and instrument memory, precise calibration of the instrument against standard waters, and improvements to the spectroscopic analyses. The CRDS system will also be coupled to continuous-flow systems for ice core analysis, in collaboration with the University of Colorado, Boulder. The goal is to have an operational system available for ice core processing associated with the next major U.S.-led ice core project at South Pole, in 2015-2017. The broader impacts of the research include the ability to measure 17O-excess in ambient atmospheric water vapor, which can be used to improve understanding of convection, moisture transport, and condensation. The instrument development work proposed here is relevant to research supported by several NSF-GEO programs, including Hydrology, Climate and Large Scale Dynamics, Paleoclimate, Atmosphere Chemistry, and both the Arctic and Antarctic Programs. This proposal will support a postdoctoral researcher.", "east": 106.0, "geometry": "POINT(106 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -77.5, "title": "Development of a Laser Spectroscopy System for Analysis of 17Oexcess on Ice Cores", "uid": "p0000316", "west": 106.0}, {"awards": "1246223 Hastings, Meredith", "bounds_geometry": "POINT(-112.1115 -79.481)", "dataset_titles": "WAIS Divide WDC06A Nitrate Isotope Record", "datasets": [{"dataset_uid": "601022", "doi": "10.15784/601022", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Nitrate; WAIS divide; WAIS Divide Ice Core", "people": "Hastings, Meredith; Buffen, Aron", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide WDC06A Nitrate Isotope Record", "url": "https://www.usap-dc.org/view/dataset/601022"}], "date_created": "Tue, 02 May 2017 00:00:00 GMT", "description": "Hastings/1246223\u003cbr/\u003e\u003cbr/\u003eThis award supports a project with the aim of distinguishing the sources of nitrate deposition to the West Antarctic Ice Sheet (WAIS) using isotopic ratios snow in archive snow and ice samples. The isotopic composition of nitrate has been shown to contain information about the source of the nitrate (i.e. nitrogen oxides = NOx = NO+NO2) and the oxidation processes that convert NOx to nitrate in the atmosphere prior to deposition. A difficulty in interpreting records in the context of NOx sources is that nitrate can be post-depositionally processed in surface snow, such that the archived record does not reflect the composition of the atmosphere. This intellectual merit of this work specifically aims to investigate variability in the isotopic composition of nitrate in snow and ice from the WAIS in the context of accumulation rate, NOx source emissions, and atmospheric chemistry. These records will be interpreted in the context of our understanding of biospheric (biomass burning, microbial processes in soils), atmospheric (lightning, transport, chemistry), and climate (temperature, accumulation rate) changes over time. A graduate student will be supported as part of this project, and both graduate student and PI will be involved in communicating the utility and results of polar research to elementary school students in the Providence, RI area. The broader impacts of the project also include making efforts to attract more young, female scientists to polar research by establishing a connection between the Earth Science Women\u0027s Network (ESWN), an organization PI Hastings helped to establish, and the Association of Polar Early Career Scientists (APECS). Finally, results of all measurements will be presented at relevant conferences, made available publicly and published in peer-reviewed journals.", "east": -112.1115, "geometry": "POINT(-112.1115 -79.481)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -79.481, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hastings, Meredith", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "Investigating Source, Chemistry and Climate changes using the Isotopic Composition of Nitrate in Antarctic Snow and Ice", "uid": "p0000399", "west": -112.1115}, {"awards": "1142166 McConnell, Joseph", "bounds_geometry": "POINT(-112.1115 -79.481)", "dataset_titles": "WAIS Divide Ice-Core Aerosol Records from 1300 to 3404 m", "datasets": [{"dataset_uid": "601008", "doi": "10.15784/601008", "keywords": "Aerosol; Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS divide; WAIS Divide Ice Core", "people": "McConnell, Joseph", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice-Core Aerosol Records from 1300 to 3404 m", "url": "https://www.usap-dc.org/view/dataset/601008"}], "date_created": "Tue, 25 Apr 2017 00:00:00 GMT", "description": "McConnell/1142166\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to use unprecedented aerosol and continuous gas (methane, carbon monoxide) measurements of the deepest section of the West Antarctic Ice Sheet (WAIS) Divide ice core to investigate rapid climate changes in Antarctica during the ~60,000 year long Marine Isotope Stage 3 period of the late Pleistocene. These analyses, combined with others, will take advantage of the high snow accumulation of the WAIS Divide ice core to yield the highest time resolution glaciochemical and gas record of any deep Antarctic ice core for this time period. The research will expand already funded discrete gas measurements and extend currently funded continuous aerosol measurements on the WAIS Divide ice core from ~25,000 to ~60,000 years before present, spanning Heinrich events 3 to 6 and Antarctic Isotope Maximum (AIM, corresponding to the Northern Hemisphere Dansgaard-Oeschger) events 3 to 14. With other high resolution Greenland cores and lower resolution Antarctic cores, the combined record will yield new insights into worldwide climate dynamics and abrupt change. The intellectual merit of the work is that it will be used to address the science goals of the WAIS Divide project including the identification of dust and biomass burning tracers such as black carbon and carbon monoxide which reflect mid- and low-latitude climate and atmospheric circulation patterns, and fallout from these sources affects marine and terrestrial biogeochemical cycles. Similarly, sea salt and ocean productivity tracers reflect changes in sea ice extent, marine primary productivity, wind speeds above the ocean, and atmospheric circulation. Volcanic tracers address the relationship between northern, tropical, and southern climates as well as stability of the West Antarctic ice sheet and sea level change. When combined with other gas records from WAIS Divide, the records developed here will transform understanding of mid- and low-latitude drivers of Antarctic, Southern Hemisphere, and global climate rapid changes and the timing of such changes. The broader impacts of the work are that it will enhance infrastructure through expansion of continuous ice core analytical techniques, train students and support collaboration between two U.S. institutions (DRI and OSU). All data will be made available to the scientific community and the public and will include participation the WAIS Divide Outreach Program. Extensive graduate and undergraduate student involvement is planned. Student recruitment will be made from under-represented groups building on a long track record. Broad outreach will be achieved through collaborations with the global and radiative modeling communities, NESTA-related and other educational outreach efforts, and public lectures. This proposed project does not require field work in the Antarctic.", "east": -112.1115, "geometry": "POINT(-112.1115 -79.481)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -79.481, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "McConnell, Joseph", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "Collaborative Research: Investigating Upper Pleistocene Rapid Climate Change using Continuous, Ultra-High-Resolution Aerosol and Gas Measurements in the WAIS Divide Ice Core", "uid": "p0000287", "west": -112.1115}, {"awards": "0538049 Steig, Eric; 0538520 Thiemens, Mark", "bounds_geometry": "POINT(-112.085 -79.5)", "dataset_titles": "Multiple Isotope Analysis of Sulfate in the West Antarctic Ice Sheet Divide Ice Core; WAIS Divide sulfate and nitrate isotopes; WAIS ice core isotope data #387, 385 (full data link not provided)", "datasets": [{"dataset_uid": "601007", "doi": "10.15784/601007", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Nitrate; Oxygen Isotopes; Sulfate; WAIS divide; WAIS Divide Ice Core", "people": "Alexander, Becky; Steig, Eric J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide sulfate and nitrate isotopes", "url": "https://www.usap-dc.org/view/dataset/601007"}, {"dataset_uid": "609479", "doi": "10.7265/N5BG2KXH", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; WAIS divide; WAIS Divide Ice Core", "people": "Thiemens, Mark H.", "repository": "USAP-DC", "science_program": null, "title": "Multiple Isotope Analysis of Sulfate in the West Antarctic Ice Sheet Divide Ice Core", "url": "https://www.usap-dc.org/view/dataset/609479"}, {"dataset_uid": "002512", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "WAIS ice core isotope data #387, 385 (full data link not provided)", "url": "http://www.waisdivide.unh.edu/"}], "date_created": "Tue, 25 Apr 2017 00:00:00 GMT", "description": "0538520\u003cbr/\u003eThiemens\u003cbr/\u003eThis award supports a project to develop the first complete record of multiple isotope ratios of nitrate and sulfate covering the last ~100,000 years, from the deep ice core planned for the central ice divide of the West Antarctic Ice Sheet (WAIS). The WAIS Divide ice core will be the highest resolution long ice core obtained from Antarctica and we can expect important complementary information to be available, including accurate knowledge of past accumulation rates, temperatures, and compounds such as H2O2, CO and CH4. These compounds play significant roles in global atmospheric chemistry and climate. Especially great potential lies in the use of multiple isotope signatures. The unique mass independent fractionation (MIF) 17O signature of ozone is observed in both nitrate and sulfate, due to the interaction of their precursors with ozone. The development of methods to measure the multiple-isotope composition of small samples of sulfate and nitrate makes continuous high resolution measurements on ice cores feasible for the first time. Recent work has shown that such measurements can be used to determine the hydroxyl radial (OH) and ozone (O3) concentrations in the paleoatmosphere as well as to apportion sulfate and nitrate sources. There is also considerable potential in using these isotope measurements to quantify post depositional changes. In the first two years, continuous measurements from the upper ~100-m of ice at WAIS divide will be obtained, to provide a detailed look at seasonal through centennial scale variability. In the third year, measurements will be made throughout the available depth of the deep core (expected to reach ~500 m at this time). The broader impacts of the project include applications to diverse fields including atmospheric chemistry, glaciology, meteorology, and paleoclimatology. Because nitrate and sulfate are important atmospheric pollutants, the results will also have direct and relevance to global environmental policy. This project will coincide with the International Polar Year (2007-2008), and contributes to goals of the IPY, which include the fostering of interdisciplinary research toward enhanced understanding of atmospheric chemistry and climate in the polar regions.", "east": -112.085, "geometry": "POINT(-112.085 -79.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Sulfate; West Antarctic; Accumulation Rates; isotope ratios; mass independent fractionation; Oxygen Isotopes; LABORATORY; Ice Core; Ice Core Data; paleoatmosphere ; isotopes; temperatures; FIELD SURVEYS; Not provided; Sulfate (SO4); FIELD INVESTIGATION; Ice Core Chemistry; Isotope", "locations": null, "north": -79.5, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Alexander, Becky; Steig, Eric J.; Thiemens, Mark H.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "Project website; USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.5, "title": "Collaborative Research: Multiple-isotope Analysis of Nitrate and Sulfate in the West Antarctic Ice Sheet Divide Ice Core", "uid": "p0000020", "west": -112.085}, {"awards": "0538427 McConnell, Joseph", "bounds_geometry": "POINT(-112.1115 -79.481)", "dataset_titles": "Gas measurement from Higgins et al., 2015 - PNAS; WAIS Divide Ice-Core Aerosol Records from 1.5 to 577 m; WAIS Divide Ice-Core Aerosol Records from Intermediate Core WDC05A; WAIS Divide Ice-Core Aerosol Records from Intermediate Core WDC05Q; WAIS Divide Ice-Core Chronology from Intermediate Core WDC05A; WAIS Divide Ice-Core Chronology from Intermediate Core WDC05Q", "datasets": [{"dataset_uid": "601010", "doi": "10.15784/601010", "keywords": "Aerosol; Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS divide; WAIS Divide Ice Core", "people": "McConnell, Joseph", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice-Core Aerosol Records from Intermediate Core WDC05A", "url": "https://www.usap-dc.org/view/dataset/601010"}, {"dataset_uid": "601014", "doi": "10.15784/601014", "keywords": "Allan Hills; Antarctica; Argon; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope", "people": "Higgins, John", "repository": "USAP-DC", "science_program": null, "title": "Gas measurement from Higgins et al., 2015 - PNAS", "url": "https://www.usap-dc.org/view/dataset/601014"}, {"dataset_uid": "601013", "doi": "10.15784/601013", "keywords": "Antarctica; Cryosphere; Depth-Age-Model; Geochronology; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS divide; WAIS Divide Ice Core", "people": "McConnell, Joseph", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice-Core Chronology from Intermediate Core WDC05Q", "url": "https://www.usap-dc.org/view/dataset/601013"}, {"dataset_uid": "601012", "doi": "10.15784/601012", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; Snow Accumulation; WAIS divide; WAIS Divide Ice Core", "people": "McConnell, Joseph", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice-Core Chronology from Intermediate Core WDC05A", "url": "https://www.usap-dc.org/view/dataset/601012"}, {"dataset_uid": "601011", "doi": "10.15784/601011", "keywords": "Aerosol; Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS divide; WAIS Divide Ice Core", "people": "McConnell, Joseph", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice-Core Aerosol Records from Intermediate Core WDC05Q", "url": "https://www.usap-dc.org/view/dataset/601011"}, {"dataset_uid": "601009", "doi": "10.15784/601009", "keywords": "Aerosol; Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS divide; WAIS Divide Ice Core", "people": "McConnell, Joseph", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice-Core Aerosol Records from 1.5 to 577 m", "url": "https://www.usap-dc.org/view/dataset/601009"}], "date_created": "Tue, 25 Apr 2017 00:00:00 GMT", "description": "0538427\u003cbr/\u003eMcConnell \u003cbr/\u003eThis award supports a project to use unique, high-depth-resolution records of a range of elements, chemical species, and ice properties measured in two WAIS Divide shallow ice cores and one shallow British ice core from West Antarctic to address critical paleoclimate, environmental, and ice-sheet mass-balance questions. Recent development of the CFA-TE method for ice-core analysis presents the opportunity to develop high-resolution, broad-spectrum glaciochemical records at WAIS Divide at relatively modest cost. Together with CFA-TE measurements from Greenland and other Antarctic sites spanning recent decades to centuries, these rich data will open new avenues for using glaciochemical data to investigate environmental and global changes issues ranging from anthropogenic and volcanic-trace-element fallout to changes in hemispheric-scale circulation, biogeochemistry, rapid-climate-change events, long-term climate change, and ice-sheet mass balance. As part of the proposed research, collaborations with U.S., Argentine, and British researchers will be initiated and expanded to directly address three major IPY themes (i.e., present environmental status, past and present environmental and human change, and polar-global interactions). Included in the contributions from these international collaborators will be ice-core samples, ice-core and meteorological model data, and extensive expertise in Antarctic glaciology, climatology, meteorology, and biogeochemistry. The broader impacts of the work include the training of students. The project will partially support one Ph.D. student and hourly undergraduate involvement. Every effort will be made to attract students from underrepresented groups to these positions. To address the challenge of introducing results of scientific research to the public policy debate, we will continue efforts to publish findings in high visibility journals, provide research results to policy makers, and work with the NSF media office to reach the public through mass-media programs. K-12 teacher and classroom involvement will be realized through outreach to local schools and NSF\u0027s Teachers Experiencing the Antarctic and Arctic (or similar) program in collaboration with WAIS Divide and other polar researchers.", "east": -112.1115, "geometry": "POINT(-112.1115 -79.481)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -79.481, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bender, Michael; McConnell, Joseph", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "Trace and Ultra-Trace Chemistry Measurements of the WAIS Divide Ice Core", "uid": "p0000148", "west": -112.1115}, {"awards": "1043554 Willenbring, Jane", "bounds_geometry": "POINT(161.5 -77.5)", "dataset_titles": "Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins", "datasets": [{"dataset_uid": "600379", "doi": "10.15784/600379", "keywords": "Antarctica; Chemistry:Rock; Cosmogenic Radionuclides; Cryosphere; Geochronology; Glaciers/Ice Sheet; Glaciology; Isotope; Sample/Collection Description; Transantarctic Mountains", "people": "Willenbring, Jane", "repository": "USAP-DC", "science_program": null, "title": "Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins", "url": "https://www.usap-dc.org/view/dataset/600379"}], "date_created": "Wed, 09 Nov 2016 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to address the question of whether ice surface melting zones developed at high elevations during warm climatic phases in the Transantarctic Mountains. Evidence from sediment cores drilled by the ANDRILL program indicates that open water in the Ross Sea could have been a source of warmth during Pliocene and Pleistocene. The question is whether marine warmth penetrated inland to the ice sheet margins. The glacial record may be ill suited to answer this question, as cold-based glaciers may respond too slowly to register brief warmth. Questions also surround possible orbital controls on regional climate and ice sheet margins. Northern Hemisphere insolation at obliquity and precession timescales is thought to control Antarctic climate through oceanic or atmospheric connections, but new thinking suggests that the duration of Southern Hemisphere summer may be more important. The PIs propose to use high elevation alluvial deposits in the Transantarctic Mountains as a proxy for inland warmth. These relatively young fans, channels, and debris flow levees stand out as visible evidence for the presence of melt water in an otherwise ancient, frozen landscape. Based on initial analyses of an alluvial fan in the Olympus Range, these deposits are sensitive recorders of rare melt events that occur at orbital timescales. For their study they will 1) map alluvial deposits using aerial photography, satellite imagery and GPS assisted field surveys to establish water sources and to quantify parameters effecting melt water production, 2) date stratigraphic sequences within these deposits using OSL, cosmogenic nuclide, and interbedded volcanic ash chronologies, 3) use paired nuclide analyses to estimate exposure and burial times, and rates of deposition and erosion, and 4) use micro and regional scale climate modeling to estimate paleoenvironmental conditions associated with melt events.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis study will produce a record of inland melting from sites adjacent to ice sheet margins to help determine controls on regional climate along margins of the East Antarctic Ice Sheet to aid ice sheet and sea level modeling studies. The proposal will support several graduate and undergraduates. A PhD student will be supported on existing funding. The PIs will work with multiple K 12 schools to conduct interviews and webcasts from Antarctica and they will make follow up visits to classrooms after the field season is complete.", "east": 161.5, "geometry": "POINT(161.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Willenbring, Jane", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.5, "title": "Collaborative Research: Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins", "uid": "p0000429", "west": 161.5}, {"awards": "1043167 White, James; 1043092 Steig, Eric", "bounds_geometry": "POINT(-112.08 -79.47)", "dataset_titles": "Resampling of Deep Polar Ice Cores using Information Theory; Seasonal temperatures in West Antarctica during the Holocene ; Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "datasets": [{"dataset_uid": "601603", "doi": "10.15784/601603", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; ice cores; Seasonality; Seasonal Temperatures; Temperature; Water Isotopes; West Antarctic Ice Sheet", "people": "Jones, Tyler R.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Seasonal temperatures in West Antarctica during the Holocene ", "url": "https://www.usap-dc.org/view/dataset/601603"}, {"dataset_uid": "601365", "doi": "10.15784/601365", "keywords": "Antarctica; Cryosphere; Delta 18O; Isotope; WAIS divide; WAIS Divide Ice Core; West Antarctic Ice Sheet", "people": "Garland, Joshua; Morris, Valerie; White, James; Vaughn, Bruce; Jones, Tyler R.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Resampling of Deep Polar Ice Cores using Information Theory", "url": "https://www.usap-dc.org/view/dataset/601365"}, {"dataset_uid": "600169", "doi": "10.15784/600169", "keywords": "Antarctica; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Paleoclimate; Snow Accumulation; WAIS divide; WAIS Divide Ice Core", "people": "White, James; Vaughn, Bruce; Jones, Tyler R.; Morris, Valerie", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "url": "https://www.usap-dc.org/view/dataset/600169"}, {"dataset_uid": "601274", "doi": "10.15784/601274", "keywords": "Antarctica; Cryosphere; Delta 18O; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Snow/Ice; WAIS divide; WAIS Divide Ice Core; West Antarctic Ice Sheet", "people": "Jones, Tyler R.; Bradley, Elizabeth; Morris, Valerie; White, James; Vaughn, Bruce; Garland, Joshua; Price, Michael", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "url": "https://www.usap-dc.org/view/dataset/601274"}], "date_created": "Thu, 15 Sep 2016 00:00:00 GMT", "description": "Steig/1043092\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to contribute one of the cornerstone analyses, stable isotopes of ice (Delta-D, Delta-O18) to the ongoing West Antarctic Ice Sheet Divide (WAIS) deep ice core. The WAIS Divide drilling project, a multi-institution project to obtain a continuous high resolution ice core record from central West Antarctica, reached a depth of 2560 m in early 2010; it is expected to take one or two more field seasons to reach the ice sheet bed (~3300 m), plus an additional four seasons for borehole logging and other activities including proposed replicate coring. The current proposal requests support to complete analyses on the WAIS Divide core to the base, where the age will be ~100,000 years or more. These analyses will form the basis for the investigation of a number of outstanding questions in climate and glaciology during the last glacial period, focused on the dynamics of the West Antarctic Ice Sheet and the relationship of West Antarctic climate to that of the Northern polar regions, the tropical Pacific, and the rest of the globe, on time scales ranging from years to tens of thousands of years. One new aspect of this work is the growing expertise at the University of Washington in climate modeling with isotope-tracer-enabled general circulation models, which will aid in the interpretation of the data. Another major new aspect is the completion and use of a high-resolution, semi-automated sampling system at the University of Colorado, which will permit the continuous analysis of isotope ratios via laser spectroscopy, at an effective resolution of ~2 cm or less, providing inter-annual time resolution for most of the core. Because continuous flow analyses of stable ice isotopes is a relatively new measurement, we will complement them with parallel measurements, every ~10-20 m, using traditional discrete sampling and analysis by mass spectrometry at the University of Washington. The intellectual merit and the overarching goal of the work are to see Inland WAIS become the reference ice isotope record for West Antarctica. The broader impacts of the work are that the data generated in this project pertain directly to policy-relevant and immediate questions of the stability of the West Antarctic ice sheet, and thus past and future changes in sea level, as well as the nature of climate change in the high southern latitudes. The project will also contribute to the development of modern isotope analysis techniques using laser spectroscopy, with applications well beyond ice cores. The project will involve a graduate student and postdoc who will work with both P.I.s, and spend time at both institutions. Data will be made available rapidly through the Antarctic Glaciological Data Center, for use by other researchers and the public.", "east": -112.08, "geometry": "POINT(-112.08 -79.47)", "instruments": null, "is_usap_dc": true, "keywords": "LABORATORY", "locations": null, "north": -79.47, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "White, James; Vaughn, Bruce; Jones, Tyler R.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.47, "title": "Collaborative Research: Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "uid": "p0000078", "west": -112.08}, {"awards": "0838936 Brook, Edward; 0839031 Severinghaus, Jeffrey", "bounds_geometry": "POINT(161.75 -77.75)", "dataset_titles": "Measurements of 14C-methane for the Younger Dryas - Preboreal Transition from Taylor Glacier, Antarctica; Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica; Taylor Glacier chemistry data and Taylor Dome TD2015 time scale; Taylor Glacier CO2 record; Taylor Glacier Gas Isotope Data", "datasets": [{"dataset_uid": "601029", "doi": "10.15784/601029", "keywords": "Antarctica; Chemistry:Rock; Critical Zone; Cryosphere; Geochemistry; Methane; Paleoclimate; Sample/Collection Description; Solid Earth; Taylor Glacier; Transantarctic Mountains; Younger Dryas", "people": "Petrenko, Vasilii; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Measurements of 14C-methane for the Younger Dryas - Preboreal Transition from Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601029"}, {"dataset_uid": "601033", "doi": "10.15784/601033", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciology; Ice Core Records; Isotope; Solid Earth; Taylor Glacier; Transantarctic Mountains", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Taylor Glacier Gas Isotope Data", "url": "https://www.usap-dc.org/view/dataset/601033"}, {"dataset_uid": "601103", "doi": "10.15784/601103", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Horizontal Ice Core; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Taylor Glacier chemistry data and Taylor Dome TD2015 time scale", "url": "https://www.usap-dc.org/view/dataset/601103"}, {"dataset_uid": "000158", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Taylor Glacier CO2 record", "url": "ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/taylor/taylor2016d13co2.txt"}, {"dataset_uid": "600165", "doi": "10.15784/600165", "keywords": "Antarctica; Cosmogenic; Cryosphere; Geochemistry; Ice Core Records; Paleoclimate; Radiocarbon; Taylor Glacier; Transantarctic Mountains", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600165"}], "date_created": "Tue, 29 Mar 2016 00:00:00 GMT", "description": "Severinghaus/0839031 \u003cbr/\u003e\u003cbr/\u003eThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop a precise gas-based chronology for an archive of large-volume samples of the ancient atmosphere, which would enable ultra-trace gas measurements that are currently precluded by sample size limitations of ice cores. The intellectual merit of the proposed work is that it will provide a critical test of the \"clathrate hypothesis\" that methane clathrates contributed to the two abrupt atmospheric methane concentration increases during the last deglaciation 15 and 11 kyr ago. This approach employs large volumes of ice (\u003e1 ton) to measure carbon-14 on past atmospheric methane across the abrupt events. Carbon-14 is an ideal discriminator of fossil sources of methane to the atmosphere, because most methane sources (e.g., wetlands, termites, biomass burning) are rich in carbon-14, whereas clathrates and other fossil sources are devoid of carbon-14. The proposed work is a logical extension to Taylor Glacier, Antarctica, of an approach pioneered at the margin of the Greenland ice sheet over the past 7 years. The Greenland work found higher-than-expected carbon-14 values, likely due in part to contaminants stemming from the high impurity content of Greenland ice and the interaction of the ice with sediments from the glacier bed. The data also pointed to the possibility of a previously unknown process, in-situ cosmogenic production of carbon-14 methane (radiomethane) in the ice matrix. Antarctic ice in Taylor Glacier is orders of magnitude cleaner than the ice at the Greenland site, and is much colder and less stratigraphically disturbed, offering the potential for a clear resolution of this puzzle and a definitive test of the cosmogenic radiomethane hypothesis. Even if cosmogenic radiomethane in ice is found, it still may be possible to reconstruct atmospheric radiomethane with a correction enabled by a detailed understanding of the process, which will be sought by co-measuring carbon-14 in carbon monoxide and carbon dioxide. The broader impacts of the proposed work are that the clathrate test may shed light on the stability of the clathrate reservoir and its potential for climate feedbacks under human-induced warming. Development of Taylor Glacier as a \"horizontal ice core\" would provide a community resource for other researchers. Education of one postdoc, one graduate student, and one undergraduate, would add to human resources. This award has field work in Antarctica.", "east": 161.75, "geometry": "POINT(161.75 -77.75)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; Not provided; USAP-DC", "locations": null, "north": -77.75, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Brook, Edward J.; Severinghaus, Jeffrey P.", "platforms": "Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "NCEI; USAP-DC", "science_programs": null, "south": -77.75, "title": "Collaborative Research: A \"Horizontal Ice Core\" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica", "uid": "p0000099", "west": 161.75}, {"awards": "0944653 Forster, Richard", "bounds_geometry": "POLYGON((-119.4 -78.1,-118.46000000000001 -78.1,-117.52000000000001 -78.1,-116.58 -78.1,-115.64 -78.1,-114.7 -78.1,-113.76 -78.1,-112.82000000000001 -78.1,-111.88 -78.1,-110.94 -78.1,-110 -78.1,-110 -78.28999999999999,-110 -78.47999999999999,-110 -78.67,-110 -78.86,-110 -79.05,-110 -79.24,-110 -79.42999999999999,-110 -79.62,-110 -79.81,-110 -80,-110.94 -80,-111.88 -80,-112.82000000000001 -80,-113.76 -80,-114.7 -80,-115.64 -80,-116.58 -80,-117.52000000000001 -80,-118.46000000000001 -80,-119.4 -80,-119.4 -79.81,-119.4 -79.62,-119.4 -79.42999999999999,-119.4 -79.24,-119.4 -79.05,-119.4 -78.86,-119.4 -78.67,-119.4 -78.47999999999999,-119.4 -78.28999999999999,-119.4 -78.1))", "dataset_titles": "Annual Satellite Era Accumulation Patterns Over WAIS Divide: A Study Using Shallow Ice Cores, Near-Surface Radars and Satellites", "datasets": [{"dataset_uid": "600146", "doi": "10.15784/600146", "keywords": "Airborne Radar; Antarctica; Cryosphere; Geology/Geophysics - Other; Glaciers/Ice Sheet; Glaciology; Radar; WAIS divide; WAIS Divide Ice Core", "people": "Forster, Richard", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Annual Satellite Era Accumulation Patterns Over WAIS Divide: A Study Using Shallow Ice Cores, Near-Surface Radars and Satellites", "url": "https://www.usap-dc.org/view/dataset/600146"}], "date_created": "Fri, 20 Nov 2015 00:00:00 GMT", "description": "This award supports a project to broaden the knowledge of annual accumulation patterns over the West Antarctic Ice Sheet by processing existing near-surface radar data taken on the US ITASE traverse in 2000 and by gathering and validating new ultra/super-high-frequency (UHF) radar images of near surface layers (to depths of ~15 m), expanding abilities to monitor recent annual accumulation patterns from point source ice cores to radar lines. Shallow (15 m) ice cores will be collected in conjunction with UHF radar images to confirm that radar echoed returns correspond with annual layers, and/or sub-annual density changes in the near-surface snow, as determined from ice core stable isotopes. This project will additionally improve accumulation monitoring from space-borne instruments by comparing the spatial-radar-derived-annual accumulation time series to the passive microwave time series dating back over 3 decades and covering most of Antarctica. The intellectual merit of this project is that mapping the spatial and temporal variations in accumulation rates over the Antarctic ice sheet is essential for understanding ice sheet responses to climate forcing. Antarctic precipitation rate is projected to increase up to 20% in the coming century from the predicted warming. Accumulation is a key component for determining ice sheet mass balance and, hence, sea level rise, yet our ability to measure annual accumulation variability over the past 5 decades (satellite era) is mostly limited to point-source ice cores. Developing a radar and ice core derived annual accumulation dataset will provide validation data for space-born remote sensing algorithms, climate models and, additionally, establish accumulation trends. The broader impacts of the project are that it will advance discovery and understanding within the climatology, glaciology and remote sensing communities by verifying the use of UHF radars to monitor annual layers as determined by visual, chemical and isotopic analysis from corresponding shallow ice cores and will provide a dataset of annual to near-annual accumulation measurements over the past ~5 decades across WAIS divide from existing radar data and proposed radar data. By determining if temporal changes in the passive microwave signal are correlated with temporal changes in accumulation will help assess the utility of passive microwave remote sensing to monitor accumulation rates over ice sheets for future decades. The project will promote teaching, training and learning, and increase representation of underrepresented groups by becoming involved in the NASA History of Winter project and Thermochron Mission and by providing K-12 teachers with training to monitor snow accumulation and temperature here in the US, linking polar research to the student?s backyard. The project will train both undergraduate and graduate students in polar research and will encouraging young investigators to become involved in careers in science. In particular, two REU students will participate in original research projects as part of this larger project, from development of a hypothesis to presentation and publication of the results. The support of a new, young woman scientist will help to increase gender diversity in polar research.", "east": -110.0, "geometry": "POINT(-114.7 -79.05)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -78.1, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Forster, Richard", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -80.0, "title": "Collaborative Research: Annual satellite era accumulation patterns over WAIS Divide: A study using shallow ice cores, near-surface radars and satellites", "uid": "p0000079", "west": -119.4}, {"awards": "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; Dronning Maud Land; Geochemistry; Geochronology; Solid Earth", "people": "Marschall, Horst", "repository": "USAP-DC", "science_program": null, "title": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antarctica", "url": "https://www.usap-dc.org/view/dataset/600135"}], "date_created": "Fri, 23 Oct 2015 00:00:00 GMT", "description": "Geochemical studies of single mineral grains in rocks can be probed to reconstruct the history of our planet. The mineral zircon (ZrSiO4) is of unique importance in that respect because of its reliability as a geologic clock due to its strong persistence against weathering, transport and changes in temperature and pressure. Uranium-Lead (U-Pb) dating of zircon grains is, perhaps, the most frequently employed method of extracting time information on geologic processes that shaped the continental crust, and has been used to constrain the evolution of continents and mountain belts through time. In addition, the isotopic composition of the element Hafnium (Hf) in zircon is used to date when the continental crust was generated by extraction of magma from the underlying mantle. Melting of rocks in the mantle and deep in the continental crust are key processes in the evolution of the continents, and they are recorded in the Hf isotopic signatures of zircon. Although the analytical procedures for U-Pb dating and Hf isotope analyses of zircon are robust now, our understanding of zircon growth and its exchange of elements and isotopes with its surrounding rock or magma are still underdeveloped. The focus of the proposed study, therefore, is to unravel the evolution of zircon Hf isotopes in rocks that were formed deep in the Earth?s crust, and more specifically, to apply these isotopic methods to rocks collected in Dronning Maud Land (DML), East Antarctica.\u003cbr/\u003e\u003cbr/\u003eDronning Maud Land (DML) occupied a central location during the formation of supercontinents ? large landmasses made up of all the continents that exist today - more than 500 million years ago. It is currently thought that supercontinents were formed and dismembered five or six times throughout Earth?s history. The area of DML is key for understanding the formation history of the last two supercontinents. The boundaries of continents that were merged to form those supercontinents are most likely hidden in DML. In this study, the isotopic composition of zircon grains recovered from DML rocks will be employed to identify these boundaries across an extensive section through the area. The rock samples were collected by the investigator during a two-month expedition to Antarctica in the austral summer of 2007?2008. The results of dating and isotope analyses of zircon of the different DML crustal domains will deliver significant insight into the regional geology of East Antarctica and its previous northern extension into Africa. This has significance for the reconstruction of the supercontinents and defining the continental boundaries in DML.", "east": 4.18, "geometry": "POINT(-1.13 -72.27)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -71.93, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Marschall, Horst", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.61, "title": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antacrtica", "uid": "p0000448", "west": -6.44}, {"awards": "0739575 Emslie, Steven", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Egg membrane and chick feather THg concentration and stable isotope composition; Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica", "datasets": [{"dataset_uid": "601459", "doi": "10.15784/601459", "keywords": "Adelie Penguin; Antarctica; Antarctic Peninsula; Cryosphere; Mercury ; Penguin", "people": "McKenzie, Ashley", "repository": "USAP-DC", "science_program": null, "title": "Egg membrane and chick feather THg concentration and stable isotope composition", "url": "https://www.usap-dc.org/view/dataset/601459"}, {"dataset_uid": "600145", "doi": "10.15784/600145", "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Geochronology; Global; Penguin; Ross Sea; Sample/Collection Description; Scotia Sea; Southern Ocean", "people": "Emslie, Steven; Polito, Michael; Patterson, William", "repository": "USAP-DC", "science_program": null, "title": "Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica", "url": "https://www.usap-dc.org/view/dataset/600145"}], "date_created": "Fri, 25 Sep 2015 00:00:00 GMT", "description": "The research combines interdisciplinary study in geology, paleontology, and biology, using stable isotope and radiocarbon analyses, to examine how climate change and resource utilization have influenced population distribution, movement, and diet in penguins during the mid-to-late Holocene. Previous investigations have demonstrated that abandoned colonies contain well-preserved remains that can be used to examine differential responses of penguins to climate change in various sectors of Antarctica. As such, the research team will investigate abandoned and active pygoscelid penguin (Adelie, Chinstrap, and Gentoo) colonies in the Antarctic Peninsula and Ross Sea regions, and possibly Prydz Bay, in collaboration with Chinese scientists during four field seasons. Stable isotope analyses will be conducted on recovered penguin tissues and prey remains in guano to address hypotheses on penguin occupation history, population movement, and diet in relation to climate change since the late Pleistocene. The study will include one Ph.D., two Masters and 16 undergraduate students in advanced research over the project period. Students will be exposed to a variety of fields, the scientific method, and international scientific research. They will complete field and lab research for individual projects or Honor\u0027s theses for academic credit. The project also will include web-based outreach, lectures to middle school students, and the development of interactive exercises that highlight hypothesis-driven research and the ecology of Antarctica. Two undergraduate students in French and Spanish languages at UNCW will be hired to assist in translating the Web page postings for broader access to this information.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "AMD/US; USA/NSF; AMD; USAP-DC; FIELD INVESTIGATION", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Emslie, Steven; Polito, Michael; Patterson, William", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica", "uid": "p0000317", "west": -180.0}, {"awards": "1043421 Severinghaus, Jeffrey; 1043522 Brook, Edward", "bounds_geometry": "POINT(-112.09 -79.47)", "dataset_titles": "WAIS Divide Replicate Core Methane Isotopic Data Set", "datasets": [{"dataset_uid": "601059", "doi": "10.15784/601059", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; WAIS divide; WAIS Divide Ice Core", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Replicate Core Methane Isotopic Data Set", "url": "https://www.usap-dc.org/view/dataset/601059"}], "date_created": "Mon, 13 Jul 2015 00:00:00 GMT", "description": "1043421/Severinghaus\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to obtain samples of ice in selected intervals for replication and verification of the validity and spatial representativeness of key results in the WAIS Divide ice core, and to obtain additional ice samples in areas of intense scientific interest where demand is high. The US Ice Core Working Group recommended in 2003 that NSF pursue the means to take replicate samples, termed \"replicate coring\". This recommendation was part of an agreement to reduce the diameter of the (then) new drilling system (the DISC drill) core to 12.2 cm to lighten logistics burdens, and the science community accepted the reduction in ice sample with the understanding that replicate coring would be able to provide extra sample volume in key intervals. The WAIS Divide effort would particularly benefit from replicate coring, because of the unique quality of the expected gas record and the large samples needed for gases and gas isotopes; thus this proposal to employ replicate coring at WAIS Divide. In addition, scientific demand for ice samples has been, and will continue to be, very unevenly distributed, with the ice core archive being completely depleted in depth intervals of high scientific interest (abrupt climate changes, volcanic sulfate horizons, meteor impact horizons, for example). The broader impacts of the proposed research may include identification of leads and lags between Greenland, tropical, and Antarctic climate change, enabling critical tests of hypotheses for the mechanism of abrupt climate change. Improved understanding of volcanic impacts on atmospheric chemistry and climate may also emerge. This understanding may ultimately help improve climate models and prediction of the Earth System feedback response to ongoing human perturbation in coming centuries. Outreach and public education about climate change are integral components of the PIs\u0027 activities and the proposed work will enhance these efforts. Broader impacts also include education and training of 2 postdoctoral scholars and 1 graduate student, and invaluable field experience for the graduate and undergraduate students who will likely make up the core processing team at WAIS Divide.", "east": -112.09, "geometry": "POINT(-112.09 -79.47)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": false, "keywords": "mass spectrometery; Ice Core Gas Records; Firn Air Isotopes; LABORATORY; FIELD SURVEYS; Not provided; WAIS divide; FIELD INVESTIGATION; Ice Core", "locations": "WAIS divide", "north": -79.47, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.; Brook, Edward J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; 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": -79.47, "title": "Collaborative Research: Replicate Coring at WAIS Divide to Obtain Additional Samples at Events of High Scientific Interest", "uid": "p0000751", "west": -112.09}, {"awards": "1246148 Severinghaus, Jeffrey; 1245659 Petrenko, Vasilii; 1245821 Brook, Edward", "bounds_geometry": "POINT(162.167 -77.733)", "dataset_titles": "Gas and Dust Measurements for Taylor Glacier and Taylor Dome Ice Cores; Last Interglacial Mean Ocean Temperature; Mean Ocean Temperature in Marine Isotope Stage 4; Measurements of 14CH4 and 14CO in ice from Taylor Glacier: Last Deglaciation; N2O Concentration and Isotope Data for 74-59 ka from Taylor Glacier, Antarctica; Taylor Glacier CO2 Isotope Data 74-59 kyr; Taylor Glacier Noble Gases - Younger Dryas; The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "datasets": [{"dataset_uid": "601415", "doi": "10.15784/601415", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core Data; Ice Core Records; Paleoclimate; Paleotemperature; Taylor Glacier", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Mean Ocean Temperature in Marine Isotope Stage 4", "url": "https://www.usap-dc.org/view/dataset/601415"}, {"dataset_uid": "600163", "doi": "10.15784/600163", "keywords": "Antarctica; Atmosphere; Cryosphere; Geochemistry; Ice Core Records; Isotope; Paleoclimate; Taylor Glacier; Transantarctic Mountains", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": null, "title": "The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "url": "https://www.usap-dc.org/view/dataset/600163"}, {"dataset_uid": "601176", "doi": "10.15784/601176", "keywords": "Antarctica; CO2; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Methane; Noble Gas; Noble Gas Isotopes; Snow/Ice; Taylor Glacier; Younger Dryas", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Taylor Glacier Noble Gases - Younger Dryas", "url": "https://www.usap-dc.org/view/dataset/601176"}, {"dataset_uid": "601198", "doi": "10.15784/601198", "keywords": "Antarctica; Blue Ice Area; Chemistry:Ice; CO2; Cryosphere; Dust; Gas; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Mass Spectrometer; Methane; Nitrogen Isotopes; Oxygen Isotopes; Paleoclimate; Snow/Ice; Taylor Dome; Taylor Dome Ice Core", "people": "Severinghaus, Jeffrey P.; Baggenstos, Daniel; Bauska, Thomas; Rhodes, Rachel; McConnell, Joseph; Petrenko, Vasilii; Dyonisius, Michael; Shackleton, Sarah; Barker, Stephen; Marcott, Shaun; Brook, Edward J.; Menking, James", "repository": "USAP-DC", "science_program": null, "title": "Gas and Dust Measurements for Taylor Glacier and Taylor Dome Ice Cores", "url": "https://www.usap-dc.org/view/dataset/601198"}, {"dataset_uid": "601218", "doi": "10.15784/601218", "keywords": "Antarctica; Carbon-14; Carbon Dioxide; Chemistry:Ice; CO2; Cryosphere; Dome C Ice Core; EPICA; EPICA Dome C; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Chemistry; Ice Core Data; Ice Core Gas Records; Ice Core Records; isotope data; Last Interglacial; Mass Spectrometer; Mass Spectrometry; Methane; Oxygen; Oxygen Isotopes; Paleotemperature; Pleistocene; Snow/Ice; Taylor Dome Ice Core; Taylor Glacier", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": "Dome C Ice Core", "title": "Last Interglacial Mean Ocean Temperature", "url": "https://www.usap-dc.org/view/dataset/601218"}, {"dataset_uid": "601218", "doi": "10.15784/601218", "keywords": "Antarctica; Carbon-14; Carbon Dioxide; Chemistry:Ice; CO2; Cryosphere; Dome C Ice Core; EPICA; EPICA Dome C; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Chemistry; Ice Core Data; Ice Core Gas Records; Ice Core Records; isotope data; Last Interglacial; Mass Spectrometer; Mass Spectrometry; Methane; Oxygen; Oxygen Isotopes; Paleotemperature; Pleistocene; Snow/Ice; Taylor Dome Ice Core; Taylor Glacier", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Last Interglacial Mean Ocean Temperature", "url": "https://www.usap-dc.org/view/dataset/601218"}, {"dataset_uid": "601260", "doi": "10.15784/601260", "keywords": "Antarctica; Carbon-14; Cosmogenic; Cryosphere; Ice Core; Methane", "people": "Dyonisius, Michael; Petrenko, Vasilii", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Measurements of 14CH4 and 14CO in ice from Taylor Glacier: Last Deglaciation", "url": "https://www.usap-dc.org/view/dataset/601260"}, {"dataset_uid": "601600", "doi": "10.15784/601600", "keywords": "Antarctica; Cryosphere; Taylor Glacier", "people": "Menking, James; Bauska, Thomas; Menking, Andy; Petrenko, Vasilii; Dyonisius, Michael; Severinghaus, Jeffrey P.; Barker, Stephen; Brook, Edward J.; Buffen, Aron; Shackleton, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Taylor Glacier CO2 Isotope Data 74-59 kyr", "url": "https://www.usap-dc.org/view/dataset/601600"}, {"dataset_uid": "601398", "doi": "10.15784/601398", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Gas Records; Ice Core Records; Marine Isotope Stage 4; MIS 4; Nitrous Oxide; Pleistocene; Taylor Dome Ice Core; Taylor Glacier", "people": "Petrenko, Vasilii; Severinghaus, Jeffrey P.; Dyonisius, Michael; Menking, James; Schilt, Adrian; Shackleton, Sarah; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "N2O Concentration and Isotope Data for 74-59 ka from Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601398"}], "date_created": "Mon, 13 Jul 2015 00:00:00 GMT", "description": "This award supports a project to use the Taylor Glacier, Antarctica, ablation zone to collect ice samples for a range of paleoenvironmental studies. A record of carbon-14 of atmospheric methane (14CH4) will be obtained for the last deglaciation and the Early Holocene, together with a supporting record of CH4 stable isotopes. In-situ cosmogenic 14C content and partitioning of 14C between different species (14CH4, C-14 carbon monoxide (14CO) and C-14 carbon dioxide (14CO2)) will be determined with unprecedented precision in ice from the surface down to ~67 m. Further age-mapping of the ablating ice stratigraphy will take place using a combination of CH4, CO2, \u0026#948;18O of oxygen gas and H2O stable isotopes. High precision, high-resolution records of CO2, \u0026#948;13C of CO2, nitrous oxide (N2O) and N2O isotopes will be obtained for the last deglaciation and intervals during the last glacial period. The potential of 14CO2 and Krypton-81 (81Kr) as absolute dating tools for glacial ice will be investigated. The intellectual merit of proposed work includes the fact that the response of natural methane sources to continuing global warming is uncertain, and available evidence is insufficient to rule out the possibility of catastrophic releases from large 14C-depleted reservoirs such as CH4 clathrates and permafrost. The proposed paleoatmospheric 14CH4 record will improve our understanding of the possible magnitude and timing of CH4 release from these reservoirs during a large climatic warming. A thorough understanding of in-situ cosmogenic 14C in glacial ice (production rates by different mechanisms and partitioning between species) is currently lacking. Such an understanding will likely enable the use of in-situ 14CO in ice at accumulation sites as a reliable, uncomplicated tracer of the past cosmic ray flux and possibly past solar activity, as well as the use of 14CO2 at both ice accumulation and ice ablation sites as an absolute dating tool. Significant gaps remain in our understanding of the natural carbon cycle, as well as in its responses to global climate change. The proposed high-resolution, high-precision records of \u0026#948;13C of CO2 would provide new information on carbon cycle changes both during times of rising CO2 in a warming climate and falling CO2 in a cooling climate. N2O is an important greenhouse gas that increased by ~30% during the last deglaciation. The causes of this increase are still largely uncertain, and the proposed high-precision record of N2O concentration and isotopes would provide further insights into N2O source changes in a warming world. The broader impacts of proposed work include an improvement in our understanding of the response of these greenhouse gas budgets to global warming and inform societally important model projections of future climate change. The continued age-mapping of Taylor Glacier ablation ice will add value to this high-quality, easily accessible archive of natural environmental variability. Establishing 14CO as a robust new tracer for past cosmic ray flux would inform paleoclimate studies and constitute a valuable contribution to the study of the societally important issue of climate change. The proposed work will contribute to the development of new laboratory and field analytical systems. The data from the study will be made available to the scientific community and the broad public through the NSIDC and NOAA Paleoclimatology data centers. 1 graduate student each will be trained at UR, OSU and SIO, and the work will contribute to the training of a postdoc at OSU. 3 UR undergraduates will be involved in fieldwork and research. The work will support a new, junior UR faculty member, Petrenko. All PIs have a strong history of and commitment to scientific outreach in the forms of media interviews, participation in filming of field projects, as well as speaking to schools and the public about their research, and will continue these activities as part of the proposed work. This award has field work in Antarctica.", "east": 162.167, "geometry": "POINT(162.167 -77.733)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Not provided; USAP-DC; FIELD INVESTIGATION; Stratigraphy; FIELD SURVEYS; Antarctica; Methane; Ice Core; paleoenvironmental; Carbon Dioxide; FIXED OBSERVATION STATIONS; Stable Isotopes; Ablation Zone; Taylor Glacier; Nitrous Oxide; USA/NSF; LABORATORY; AMD; Cosmogenic; AMD/US", "locations": "Taylor Glacier; Antarctica", "north": -77.733, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Petrenko, Vasilii; Brook, Edward J.; Severinghaus, Jeffrey P.; PETRENKO, VASILLI", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e FIXED OBSERVATION STATIONS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": -77.733, "title": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "uid": "p0000283", "west": 162.167}, {"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; Cosmogenic; Cryosphere; Geochemistry; Geochronology; Glaciers/Ice Sheet; Glaciology; Reedy Glacier; 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": "FIELD SURVEYS; Aluminum-26; Exposure age; Erosion; SURFACE EXPOSURE DATES; Rock Samples; Beryllium-10", "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": "0944645 Goodge, John", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 11 Feb 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eBecause of extensive ice cover and sparse remote-sensing data, the geology of the Precambrian East Antarctic Shield (EAS) remains largely unexplored with information limited to coastal outcrops from the African, Indian and Australian sectors. The East Antarctic lithosphere is globally important: as one of the largest coherent Precambrian shields, including rocks as old as ~3.8 Ga, it played an important role in global crustal growth; it is a key piece in assembly of the Rodinia and Gondwana supercontinents; it is the substrate to Earth?s major ice cap, including numerous sub-glacial lakes, and influences its thermal state and mechanical stability; and its geotectonic association with formerly adjacent continental blocks in South Africa, India and Australia suggest that it might harbor important mineral resources. This project will increase understanding of the age and composition of the western EAS lithosphere underlying and adjacent to the Transantarctic Mountains (TAM) using U-Pb ages, and Hf- and O-isotope analysis of zircon in early Paleozoic granitoids and Pleistocene glacial tills. TAM granites of the early Paleozoic Ross Orogen represent an areally extensive continental-margin arc suite that can provide direct information about the EAS crust from which it melted and/or through which it passed. Large rock clasts of igneous and metamorphic lithologies entrained in glacial tills at the head of major outlet glaciers traversing the TAM provide eroded samples of the proximal EAS basement. Zircons in these materials will provide data about age and inheritance (U-Pb), crustal vs. mantle origin (O isotopes), and crustal sources and evolution (Hf isotopes). Integrated along a significant part of the TAM, these data will help define broader crustal provinces that can be correlated with geophysical data and used to test models of crustal assembly. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis project will provide a research opportunity for undergraduate and graduate students. Undergraduates will be involved as Research Assistants in sample preparation, imaging, and analytical procedures, and conducting their own independent research. The two main elements of this project will form the basis of MS thesis projects for two graduate students at UMD. Through this project they will gain a good understanding of petrology, isotope geochemistry, and analytical methods. The broader scientific impacts of this work are that it will help develop a better understanding of the origin and evolution of East Antarctic lithosphere underlying and adjacent to the TAM, which will be of value to the broader earth science and glaciological community. Furthermore, knowledge of East Antarctic geology is of continuing interest to the general public because of strong curiosity about past supercontinents, what?s under the ice, and the impact of global warming on ice-sheet stability.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Transantarctic Mountains; Not provided", "locations": "Transantarctic Mountains", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Goodge, John", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Age and Composition of the East Antarctic Shield by Isotopic Analysis of Granite and Glacial Till", "uid": "p0000258", "west": null}, {"awards": "0838843 Kurbatov, Andrei; 0838849 Bender, Michael", "bounds_geometry": "POLYGON((159.16667 -76.66667,159.19167 -76.66667,159.21667 -76.66667,159.24167 -76.66667,159.26667 -76.66667,159.29167 -76.66667,159.31667 -76.66667,159.34167 -76.66667,159.36667 -76.66667,159.39167 -76.66667,159.41667 -76.66667,159.41667 -76.673336,159.41667 -76.680002,159.41667 -76.686668,159.41667 -76.693334,159.41667 -76.7,159.41667 -76.706666,159.41667 -76.713332,159.41667 -76.719998,159.41667 -76.726664,159.41667 -76.73333,159.39167 -76.73333,159.36667 -76.73333,159.34167 -76.73333,159.31667 -76.73333,159.29167 -76.73333,159.26667 -76.73333,159.24167 -76.73333,159.21667 -76.73333,159.19167 -76.73333,159.16667 -76.73333,159.16667 -76.726664,159.16667 -76.719998,159.16667 -76.713332,159.16667 -76.706666,159.16667 -76.7,159.16667 -76.693334,159.16667 -76.686668,159.16667 -76.680002,159.16667 -76.673336,159.16667 -76.66667))", "dataset_titles": "Allan Hills Stable Water Isotopes; Exploring A 2 Million + Year Ice Climate Archive-Allan Hills Blue Ice Area (2MBIA)", "datasets": [{"dataset_uid": "609541", "doi": "10.7265/N5NP22DF", "keywords": "Allan Hills; Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Isotope", "people": "Mayewski, Paul A.; Introne, Douglas; Spaulding, Nicole; Kurbatov, Andrei V.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Allan Hills Stable Water Isotopes", "url": "https://www.usap-dc.org/view/dataset/609541"}, {"dataset_uid": "600099", "doi": "10.15784/600099", "keywords": "Allan Hills; Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Ice Core Records; Paleoclimate; Solid Earth", "people": "Bender, Michael", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Exploring A 2 Million + Year Ice Climate Archive-Allan Hills Blue Ice Area (2MBIA)", "url": "https://www.usap-dc.org/view/dataset/600099"}], "date_created": "Wed, 10 Dec 2014 00:00:00 GMT", "description": "This award supports a project to generate an absolute timescale for the Allan Hills Blue Ice Area (BIA), and then to reconstruct details of past climate changes and greenhouse gas concentrations for certain time periods back to 2.5 Ma. Ice ages will be determined by applying emerging methods for absolute and relative dating of trapped air bubbles (based on Argon-40/Argon-38, delta-18O of O2, and the O2/N2 ratio). To demonstrate the potential of the Allan Hills BIAs as a paleoclimate archive trenches and ice cores will be collected for age intervals corresponding to 110-140 ka, 1 Ma, and 2.5 Ma. During the proposed two field seasons a total of 6x100 m and additional 15 m cores will be combined with trenching. The intellectual merit of the proposed activity is that the results of this work will extend the landmark work of EPICA and other deep ice coring efforts, which give records dating back to 0.8 Ma, and will complement work planned by IPICS to drill a continuous Antarctic ice core extending to 1.5 Ma. The results will help to advance understanding of major climate regimes and transitions that took place between 0-2.5 Ma, including the 40 kyr world and the mid-Pleistocene climate transition. A major long-term scientific goal is to provide a transformative approach to the collection of paleoclimate records by establishing an \"International Climate Park\" in the Allan Hills BIA that would enable sampling of large quantities of known age ice as old as 2.5 Ma, by any interested American or foreign investigator. The broader impacts resulting from the proposed activity include training students who are well versed in advanced field, laboratory and numerical modeling methods combining geochemistry, glaciology, and paleoclimatology. We will include material relevant to our proposed research in our ongoing efforts in local education and in our outreach efforts for media. The University of Maine already has cyberinfrastructure, using state of the art web-based technology, which can provide a wide community of scientists with fast access to the results of our research. The work will contribute to the broad array of climate change studies that is informing worldwide understanding of natural and anthropogenic forced climate change, and the options for responding. This award has field work in Antarctica.", "east": 159.41667, "geometry": "POINT(159.29167 -76.7)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "GROUND-BASED OBSERVATIONS; LABORATORY; Deuterium Isotopes; Not provided; Oxygen Isotopes", "locations": null, "north": -76.66667, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Spaulding, Nicole; Introne, Douglas; Bender, Michael; Kurbatov, Andrei V.; Mayewski, Paul A.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.73333, "title": "Collaborative Research: Exploring A 2 Million + Year Ice Climate Archive-Allan Hills Blue Ice Area (2MBIA)", "uid": "p0000046", "west": 159.16667}, {"awards": "1043092 Steig, Eric", "bounds_geometry": null, "dataset_titles": "17O excess from WAIS Divide, 0 to 25 ka BP; WAIS Divide WDC06A Oxygen Isotope Record", "datasets": [{"dataset_uid": "601413", "doi": "10.15784/601413", "keywords": "Antarctica; Cryosphere; Ice Core; Oxygen Isotopes; WAIS divide", "people": "Schoenemann, Spruce; Steig, Eric J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "17O excess from WAIS Divide, 0 to 25 ka BP", "url": "https://www.usap-dc.org/view/dataset/601413"}, {"dataset_uid": "609629", "doi": "10.7265/N5GT5K41", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Paleoclimate; WAIS divide; WAIS Divide Ice Core", "people": "Steig, Eric J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide WDC06A Oxygen Isotope Record", "url": "https://www.usap-dc.org/view/dataset/609629"}], "date_created": "Sat, 06 Dec 2014 00:00:00 GMT", "description": "This award supports a project to contribute one of the cornerstone analyses, stable isotopes of ice (Delta-D, Delta-O18) to the ongoing West Antarctic Ice Sheet Divide (WAIS) deep ice core. The WAIS Divide drilling project, a multi-institution project to obtain a continuous high resolution ice core record from central West Antarctica, reached a depth of 2560 m in early 2010; it is expected to take one or two more field seasons to reach the ice sheet bed (~3300 m), plus an additional four seasons for borehole logging and other activities including proposed replicate coring. The current proposal requests support to complete analyses on the WAIS Divide core to the base, where the age will be ~100,000 years or more. These analyses will form the basis for the investigation of a number of outstanding questions in climate and glaciology during the last glacial period, focused on the dynamics of the West Antarctic Ice Sheet and the relationship of West Antarctic climate to that of the Northern polar regions, the tropical Pacific, and the rest of the globe, on time scales ranging from years to tens of thousands of years. One new aspect of this work is the growing expertise at the University of Washington in climate modeling with isotope-tracer-enabled general circulation models, which will aid in the interpretation of the data. Another major new aspect is the completion and use of a high-resolution, semi-automated sampling system at the University of Colorado, which will permit the continuous analysis of isotope ratios via laser spectroscopy, at an effective resolution of ~2 cm or less, providing inter-annual time resolution for most of the core. Because continuous flow analyses of stable ice isotopes is a relatively new measurement, we will complement them with parallel measurements, every ~10-20 m, using traditional discrete sampling and analysis by mass spectrometry at the University of Washington. The intellectual merit and the overarching goal of the work are to see Inland WAIS become the reference ice isotope record for West Antarctica. The broader impacts of the work are that the data generated in this project pertain directly to policy-relevant and immediate questions of the stability of the West Antarctic ice sheet, and thus past and future changes in sea level, as well as the nature of climate change in the high southern latitudes. The project will also contribute to the development of modern isotope analysis techniques using laser spectroscopy, with applications well beyond ice cores. The project will involve a graduate student and postdoc who will work with both P.I.s, and spend time at both institutions. Data will be made available rapidly through the Antarctic Glaciological Data Center, for use by other researchers and the public.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e INFRARED LASER SPECTROSCOPY; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e INFRARED LASER SPECTROSCOPY", "is_usap_dc": true, "keywords": "AGDC-project; AMD; ANALYTICAL LAB; USAP-DC; LABORATORY; AMD/US; FIELD SURVEYS; WAIS Divide-project; USA/NSF", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Steig, Eric J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": null, "title": "Collaborative Research: Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "uid": "p0000010", "west": null}, {"awards": "0944615 Brown, Michael; 0944600 Siddoway, Christine", "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": "Rock Samples (full data link not provided)", "datasets": [{"dataset_uid": "000175", "doi": "", "keywords": null, "people": null, "repository": "PRR", "science_program": null, "title": "Rock Samples (full data link not provided)", "url": "http://bprc.osu.edu/rr/"}], "date_created": "Thu, 09 Oct 2014 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe northern Ford ranges in Marie Byrd Land, Antarctica, record events and processes that transformed a voluminous succession of Lower Paleozoic turbidites intruded by calc-alkaline plutonic rocks into differentiated continental crust along the margin of Gondwana. In this study the Fosdick migmatite?granite complex will be used to investigate crustal evolution through an integrated program of fieldwork, structural geology, petrology, mineral equilibria modeling, geochronology and geochemistry. The PIs propose detailed traverses at four sites within the complex to investigate Paleozoic and Mesozoic orogenic cycles. They will use petrological associations, structural geometry, and microstructures of host gneisses and leucogranites to distinguish the migration and coalescence patterns for remnant melt flow networks, and carry out detailed sampling for geochronology, geochemistry and isotope research. Mafic plutonic phases will be sampled to acquire information about mantle contributions at the source. Mineral equilibria modeling of source rocks and granite products, combined with in situ mineral dating, will be employed to resolve the P?T?t trajectories arising from thickening/thinning of crust during orogenic cycles and to investigate melting and melt loss history. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis work involves research and educational initiatives for an early career female scientist, as well as Ph.D. and undergraduate students. Educational programs for high school audiences and undergraduate courses on interdisciplinary Antarctic science will be developed.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "structural geology; Not provided; detachment faults; tectonics; migmatite; Geochronology; gneiss dome; transcurrent faults", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Siddoway, Christine; Brown, Mike", "platforms": "Not provided", "repo": "PRR", "repositories": "PRR", "science_programs": null, "south": -90.0, "title": "Collaborative research: Polyphase Orogenesis and Crustal Differentiation in West Antarctica", "uid": "p0000259", "west": -180.0}, {"awards": "0944343 Severinghaus, Jeffrey", "bounds_geometry": "POINT(-112.05 -79.28)", "dataset_titles": null, "datasets": null, "date_created": "Fri, 15 Aug 2014 00:00:00 GMT", "description": "Severinghaus/0944343\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop both a record of past local temperature change at the WAIS Divide site, and past mean ocean temperature using solubility effects on atmospheric krypton and xenon. The two sets of products share some of the same measurements, because the local temperature is necessary to make corrections to krypton and xenon, and thus synergistically support each other. Further scientific synergy is obtained by the fact that the mean ocean temperature is constrained to vary rather slowly, on a 1000-yr timescale, due to the mixing time of the deep ocean. Thus rapid changes are not expected, and can be used to flag methodological problems if they appear in the krypton and xenon records. The mean ocean temperature record produced will have a temporal resolution of 500 years, and will cover the entire 3400 m length of the core. This record will be used to test hypotheses regarding the cause of atmospheric carbon dioxide (CO2) variations, including the notion that deep ocean stratification via a cold salty stagnant layer caused atmospheric CO2 drawdown during the last glacial period. The local surface temperature record that results will synergistically combine with independent borehole thermometry and water isotope records to produce a uniquely precise and accurate temperature history for Antarctica, on a par with the Greenland temperature histories. This history will be used to test hypotheses that the ?bipolar seesaw? is forced from the North Atlantic Ocean, which makes a specific prediction that the timing of Antarctic cooling should slightly lag abrupt Greenland warming. The WAIS Divide ice core is expected to be the premier atmospheric gas record of the past 100,000 years for the foreseeable future, and as such, making this set of high precision noble gas measurements adds value to the other gas records because they all share a common timescale and affect each other in terms of physical processes such as gravitational fractionation. Broader impact of the proposed work: The clarification of timing of atmospheric CO2 and Antarctic surface temperature, along with deep ocean temperature, will aid in efforts to understand the feedbacks among CO2, temperature, and ocean circulation. These feedbacks bear on the future response of the Earth System to anthropogenic forcing. A deeper understanding of the mechanism of deglaciation, and the role of atmospheric CO2, will go a long way towards clarifying a topic that has become quite confused in the public mind in the public debate over climate change. Elucidating the role of the bipolar seesaw in ending glaciations and triggering CO2 increases may also provide an important warning that this represents a potential positive feedback, not currently considered by IPCC. Education of one graduate student, and training of one technician, will add to the nation?s human resource base. Outreach activities will be enhanced and will to continue to entrain young people in discovery, and excitement will enhance the training of the next generation of scientists and educators.", "east": -112.05, "geometry": "POINT(-112.05 -79.28)", "instruments": null, "is_usap_dc": false, "keywords": "Nobel gases; FIELD INVESTIGATION; Climate; Xenon; FIELD SURVEYS; Ice Core; Antarctica; Krypton; LABORATORY", "locations": "Antarctica", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": -79.28, "title": "Noble Gases in the WAIS Divide Ice Core as Indicators of Local and Mean-ocean Temperature", "uid": "p0000430", "west": -112.05}, {"awards": "0944489 Williams, Trevor", "bounds_geometry": "POLYGON((-55 -58,-33.2 -58,-11.4 -58,10.4 -58,32.2 -58,54 -58,75.8 -58,97.6 -58,119.4 -58,141.2 -58,163 -58,163 -60,163 -62,163 -64,163 -66,163 -68,163 -70,163 -72,163 -74,163 -76,163 -78,141.2 -78,119.4 -78,97.6 -78,75.8 -78,54 -78,32.2 -78,10.4 -78,-11.4 -78,-33.2 -78,-55 -78,-55 -76,-55 -74,-55 -72,-55 -70,-55 -68,-55 -66,-55 -64,-55 -62,-55 -60,-55 -58))", "dataset_titles": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris", "datasets": [{"dataset_uid": "600116", "doi": "10.15784/600116", "keywords": "Cryosphere; Geochronology; George V Land; IODP U1356; IODP U1361; Marine Sediments; ODP1165; Prydz Bay; Solid Earth; Southern Ocean; Wilkes Land", "people": "Williams, Trevor; Hemming, Sidney R.", "repository": "USAP-DC", "science_program": null, "title": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris", "url": "https://www.usap-dc.org/view/dataset/600116"}], "date_created": "Wed, 13 Aug 2014 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to study the stability and dynamics of the East Antarctic ice sheet during the Pliocene in the area of the Wilkes and Aurora subglacial basins. Models indicate the ice sheet is most sensitive to warming in these low-lying areas. This study is important as there is very little direct evidence about which parts of the East Antarctic ice sheet became unstable under warm conditions. In a pilot study the PIs have shown that the isotopic geochemical signature of downcore ice-rafted debris (IRD) can be linked to continental source areas indicating which parts of the ice sheet reached the coast and calved IRD-bearing icebergs. Their initial results suggest rapid iceberg discharge from the Wilkes Land and Ad\u00e9lie Land coastal areas at times in the late Miocene and early Pliocene. In this study the PIs will analyze IRD from IODP sediment cores collected on the continental rise off East Antarctica. By analyzing 40Ar/39Ar ages of hornblende IRD grains, U-Pb ages of zircons, and Sm-Nd isotopes of the fine fraction of several IRD-rich layers for each core, they will be able to fingerprint continental source areas that will indicated ice extent and dynamics on East Antarctica. The PIs will also carry out detailed studies across a few of these layers to characterize the anatomy of the ice-rafting event and better understand the mechanism of ice destabilization.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe data collected will be important for scientists in a broad variety of fields. The project will involve one undergraduate student and one summer intern at LDEO, and a graduate student at Imperial College London. The project will expose to cutting edge methodologies as well as an international research team. Data from the project will be deposited in the online databases (SedDB) and all results and methods will be made available to the scientific community through publications in peer-reviewed journals and attendance at international conferences.", "east": 163.0, "geometry": "POINT(54 -68)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -58.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Williams, Trevor; Hemming, Sidney R.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris", "uid": "p0000353", "west": -55.0}, {"awards": "1321588 Mukasa, Samuel", "bounds_geometry": "POLYGON((129.26361 -71.3575,132.914609 -71.3575,136.565608 -71.3575,140.216607 -71.3575,143.867606 -71.3575,147.518605 -71.3575,151.169604 -71.3575,154.820603 -71.3575,158.471602 -71.3575,162.122601 -71.3575,165.7736 -71.3575,165.7736 -72.145583,165.7736 -72.933666,165.7736 -73.721749,165.7736 -74.509832,165.7736 -75.297915,165.7736 -76.085998,165.7736 -76.874081,165.7736 -77.662164,165.7736 -78.450247,165.7736 -79.23833,162.122601 -79.23833,158.471602 -79.23833,154.820603 -79.23833,151.169604 -79.23833,147.518605 -79.23833,143.867606 -79.23833,140.216607 -79.23833,136.565608 -79.23833,132.914609 -79.23833,129.26361 -79.23833,129.26361 -78.450247,129.26361 -77.662164,129.26361 -76.874081,129.26361 -76.085998,129.26361 -75.297915,129.26361 -74.509832,129.26361 -73.721749,129.26361 -72.933666,129.26361 -72.145583,129.26361 -71.3575))", "dataset_titles": "Geochemistry and Geochronology of Intraplate Lavas Recovered from the Arctic Ocean", "datasets": [{"dataset_uid": "000222", "doi": "", "keywords": null, "people": null, "repository": "EarthChem", "science_program": null, "title": "Geochemistry and Geochronology of Intraplate Lavas Recovered from the Arctic Ocean", "url": "http://dx.doi.org/10.1594/IEDA/100555"}], "date_created": "Fri, 27 Jun 2014 00:00:00 GMT", "description": "This project is a geochemical study of volcanic rocks from the West Antarctic Rift system. Its goal is to understand the link between mantle composition and the diverse, regional geodynamic processes, which include uplift, rifting, and volcanism. This project uses argon dating to time the processes, and isotope geochemistry and melt inclusion studies to determine whether the area is underlain by hot or wet mantle. The main broader impacts are support for a woman graduate student, undergraduate research, and research infrastructure.", "east": 165.7736, "geometry": "POINT(147.518605 -75.297915)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -71.3575, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Mukasa, Samuel", "platforms": "Not provided", "repo": "EarthChem", "repositories": "EarthChem", "science_programs": null, "south": -79.23833, "title": "Submarine and On-Land Volcanism in the West Antarctic Rift System: A Petrologic and Geochemical Study to Assess Melting Processes and Eruption History", "uid": "p0000494", "west": 129.26361}, {"awards": "0944662 Elliot, David; 0944532 Isbell, John", "bounds_geometry": "POLYGON((158.9 -83,159.583 -83,160.266 -83,160.949 -83,161.632 -83,162.315 -83,162.998 -83,163.681 -83,164.364 -83,165.047 -83,165.73 -83,165.73 -83.21,165.73 -83.42,165.73 -83.63,165.73 -83.84,165.73 -84.05,165.73 -84.26,165.73 -84.47,165.73 -84.68,165.73 -84.89,165.73 -85.1,165.047 -85.1,164.364 -85.1,163.681 -85.1,162.998 -85.1,162.315 -85.1,161.632 -85.1,160.949 -85.1,160.266 -85.1,159.583 -85.1,158.9 -85.1,158.9 -84.89,158.9 -84.68,158.9 -84.47,158.9 -84.26,158.9 -84.05,158.9 -83.84,158.9 -83.63,158.9 -83.42,158.9 -83.21,158.9 -83))", "dataset_titles": "Rock Samples (full data link not provided)", "datasets": [{"dataset_uid": "000171", "doi": "", "keywords": null, "people": null, "repository": "PRR", "science_program": null, "title": "Rock Samples (full data link not provided)", "url": "http://bprc.osu.edu/rr/"}], "date_created": "Thu, 05 Dec 2013 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe goal of this project is to address relationships between foreland basins and their tectonic settings by combining detrital zircon isotope characteristics and sedimentological data. To accomplish this goal the PIs will develop a detailed geochronology and analyze Hf- and O-isotopes of detrital zircons in sandstones of the Devonian Taylor Group and the Permian-Triassic Victoria Group. These data will allow them to better determine provenance and basin fill, and to understand the nature of the now ice covered source regions in East and West Antarctica. The PIs will document possible unexposed/unknown crustal terrains in West Antarctica, investigate sub-glacial terrains of East Antarctica that were exposed to erosion during Devonian to Triassic time, and determine the evolving provenance and tectonic history of the Devonian to Triassic Gondwana basins in the central Transantarctic Mountains. Detrital zircon data will be interpreted in the context of fluvial dispersal/drainage patterns, sandstone petrology, and sequence stratigraphy. This interpretation will identify source terrains and evolving sediment provenances. Paleocurrent analysis and sequence stratigraphy will determine the timing and nature of changing tectonic conditions associated with development of the depositional basins and document the tectonic history of the Antarctic sector of Gondwana. Results from this study will answer questions about the Panthalassan margin of Gondwana, the Antarctic craton, and the Beacon depositional basin and their respective roles in global tectonics and the geologic and biotic history of Antarctica. The Beacon basin and adjacent uplands played an important role in the development and demise of Gondwanan glaciation through modification of polar climates, development of peat-forming mires, colonization of the landscape by plants, and were a migration route for Mesozoic vertebrates into Antarctica. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis proposal includes support for two graduate students who will participate in the fieldwork, and also support for other students to participate in laboratory studies. Results of the research will be incorporated in classroom teaching at the undergraduate and graduate levels and will help train the next generation of field geologists. Interactions with K-12 science classes will be achieved by video/computer conferencing and satellite phone connections from Antarctica. Another outreach effort is the developing cooperation between the Byrd Polar Research Center and the Center of Science and Industry in Columbus.", "east": 165.73, "geometry": "POINT(162.315 -84.05)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e XRF", "is_usap_dc": true, "keywords": "Not provided; LABORATORY", "locations": null, "north": -83.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Elliot, David; Isbell, John", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; Not provided", "repo": "PRR", "repositories": "PRR", "science_programs": null, "south": -85.1, "title": "Collaborative Research:Application of Detrital Zircon Isotope Characteristics and Sandstone Analysis of Beacon Strata to the Tectonic Evolution of the Antarctic Sector of Gondwana", "uid": "p0000312", "west": 158.9}, {"awards": "1043367 Aciego, Sarah", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 01 Nov 2013 00:00:00 GMT", "description": "Aciego/1043367\u003cbr/\u003e\u003cbr/\u003eThis award supports the development of a new method for determining the absolute age of samples from deep ice cores. The project will: (1) prove the efficacy of the Uranium-series dating method on a high accumulation rate ice core, and (2) address the uncertainties in the age dating of the EPICA Dronning-Maud Land (EDML) ice core in the lower 300 m. The well-dated upper section of the ice core (down to 150,000 years at 2415.7 m) will provide excellent constraints to validate the ages determined by the U-series method. After verification, and possible adjustments to the laboratory chemistry, the method will be applied to a suite of ice samples of unknown age in the lower part of the EDML ice core. Within the lower 300 m of this ice core, the climate records are disturbed by tilting and folding of the ice, and, due to the uncertainties in how the ice has flowed, it is impossible to determine if accurate age dates can be obtained to access the record of climate change, or if mixing of the ice is too incoherent. As part of the methodology, the PI will measure surface area of dust included in the ice using a gas adsorption technique developed for ultra-small samples; these measurements will be made on a BET nano-scale which is to be purchased from the funding of this project. Intellectual Merit: The proposed research will contribute to our understanding of geophysical processes that fold and tilt ice. This will allow new paleoclimate records to be recovered from ice cores that have been physically deformed and disturbed and previously did not permit accurate dating. Broader Impacts: This funding will provide support for one PhD graduate student and contribute to their training as a researcher in geochemistry and paleoclimate studies. The PI will teach classes in earth surface processes (including glaciology) and in advanced isotope geochemistry. Work related to this research will be integrated as a teaching tool into the classroom to provide a hands-on, relevant learning experience. Furthermore, samples examined as part of this research will be made available from the AWI archive in Bremerhaven, Germany as part of the collaboration between the PI in the United States and the European ice core community.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Glaciology", "paleo_time": null, "persons": "Aciego, Sarah", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Detangling Flow Regimes and Paleoclimate in the Deepest Section of the EDML Ice Core using U-series Ages.", "uid": "p0000712", "west": null}, {"awards": "0839078 Brook, Edward", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 31 Oct 2013 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop a robust analytical technique for measuring the stable isotopes of CO2 in air trapped in polar ice, and to reconstruct the \u00e413C of CO2 over the last glacial to interglacial transition (20,000 to 10,000 years BP) and through the Holocene. The bulk of these measurements will be made on newly cored ice from the WAIS Divide Ice Core. A robust record \u00e413C of CO2 will be a valuable addition to the rich data produced from this project. The intellectual merit of the proposed work relates to the fact that explaining glacial-interglacial changes in atmospheric CO2 remains a major challenge for paleoclimatology. The lack of a coherent, widely accepted explanation underscores uncertainties in the basic mechanisms that control the carbon cycle, and that lack of understanding limits our ability to confidently predict how the carbon cycle will change in the future, in the face of a potentially major perturbation of both global temperature and the CO2 content of the atmosphere. A widely accepted record of this parameter could transform our understanding of how the carbon cycle and climate change are linked. The broader impacts of the work include training of graduate student at OSU who will conduct much of the lab work and will also participate in fieldwork at the WAIS Divide Core site. The student will also participate in a number of organized outreach efforts and will develop his own outreach effort, through weblogs and other communication of his research. The PIs will communicate the results from this project to a variety of audiences through academic courses and public talks. The proposed work addresses a major topic in biogeochemistry, the origin of glacial-interglacial CO2 cycles. The results are relevant to understanding changes in the carbon cycle due to human activities because the lack of clear understanding of past variations contributes to public uncertainty about the importance of modern climate change. The proposed funding will also contribute to analytical infrastructure at OSU and develop an analytical capability for an ice core measurement currently not available in the United States.", "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": "Brook, Edward J.; Mix, Alan", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Developing a glacial-interglacial record of delta-13C of atmospheric CO2", "uid": "p0000260", "west": null}, {"awards": "0823101 Ducklow, Hugh", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG1301", "datasets": [{"dataset_uid": "001425", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1301"}, {"dataset_uid": "002731", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1301", "url": "https://www.rvdata.us/search/cruise/LMG1301"}], "date_created": "Mon, 24 Jun 2013 00:00:00 GMT", "description": "Since 1990, Palmer LTER (PAL) research has been guided by the hypothesis that variability in the polar marine ecosystem is mechanistically coupled to changes in the annual advance, retreat and spatial extent of sea ice. Since that time, the hypothesis has been modified to incorporate climate migration, i.e. the displacement of a cold, dry polar climate by a warm, moist climate regime in the northern component of the PAL region, producing fundamental changes in food web structure and elemental cycling. The observed northern changes are affecting all trophic levels and elemental cycling, and the primary mechanism of change involves match-mismatch dynamics. The proposed research builds on previous findings, with a new emphasis on process studies and modeling to elucidate the mechanistic links between teleconnections, climate change, physical oceanographic forcing and ecosystem dynamics. The proposed research will examine the hypothesis that regional warming and sea ice decline associated with historical and on-going climate migration in the northern part of the study area have altered key phenological relationships, leading to changes in species distributions, increasing trophic mismatches and changes in habitat, food availability, ecosystem dynamics and biogeochemical cycling. Through targeted process studies linked to numerical model simulations, the research also will test the hypothesis that deep cross-shelf canyons characterizing the core study region are focal areas for ecosystem processes that result in predictable, elevated food resources for top-predators. The effort includes the addition of 3 new PIs: a zooplankton ecologist with expertise in biogeochemical fluxes, a phytoplankton ecologist focusing on bio-optics and autonomous observations using gliders, and a numerical simulation modeler specializing in coupled global models of ocean circulation, plankton ecology and biogeochemical cycles. The program will add trace metal sampling and analysis, moored physical oceanographic sensors, a moored sediment trap in the south, drifting sediment traps and stable carbon (del 13C) and nitrogen (del 15N) isotope analyses. Missions lasting up to 45 days using gliders deployed before, during and after summer cruises will, along with moorings and satellite remote sensing of sea ice, ocean color, sea surface temperatures and wind fields, greatly extend the observational program in space and time. \u003cbr/\u003e\u003cbr/\u003eSince its inception, PAL has been a leader in Information Management to enable knowledge-building within and beyond the Antarctic, oceanographic and LTER communities. PAL has designed and deployed a new information infrastructure with a relational database architecture to facilitate data distribution and sharing. The Education and Outreach program capitalizes on the public\u0027s fascination with Antarctica to promote scientific literacy from kindergarten students to adult citizens concerned with climate change and environmental sustainability. Through communicating results to the public and working with scientific assessment bodies (e.g., IPCC) and Antarctic Treaty parties to protect Earth\u0027s last frontier, PAL researchers contribute to the national scientific agenda and the greater public benefit.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e PROFILERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ducklow, Hugh", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": "LTER", "south": null, "title": "Palmer, Antarctica Long Term Ecological Research Project", "uid": "p0000874", "west": null}, {"awards": "1039365 Rimmer, Susan", "bounds_geometry": null, "dataset_titles": "The Permian-Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuations in Terrestrial Organic Matter", "datasets": [{"dataset_uid": "600121", "doi": "10.15784/600121", "keywords": "Antarctica; Chemistry:Rock; Geochemistry; Solid Earth; Transantarctic Mountains", "people": "Rimmer, Susan", "repository": "USAP-DC", "science_program": null, "title": "The Permian-Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuations in Terrestrial Organic Matter", "url": "https://www.usap-dc.org/view/dataset/600121"}], "date_created": "Wed, 30 Jan 2013 00:00:00 GMT", "description": "This project studies the Permian-Triassic extinction event as recorded in sedimentary rocks from the Transantarctic Mountains of Antarctica. Two hundred and fifty million years ago most life on Earth was wiped out in a geologic instant. The cause is a subject of great debate. Researchers have identified a unique stratigraphic section near Shackleton glacier laid down during the extinction event. Organic matter from these deposits will be analyzed by density gradient centrifugation (DGC), which will offer detailed information on the carbon isotope composition. The age of these layers will be precisely dated by U/Pb-zircon-dating of intercalated volcanics. Combined, these results will offer detailed constraints on the timing and duration of carbon isotope excursions during the extinction, and offer insight into the coupling of marine and terrestrial carbon cycles. \u003cbr/\u003eThe broader impacts of this project include graduate and undergraduate student research, K12 outreach and teacher involvement, and societal relevance of the results, since the P/T extinction may have been caused by phenomena such as methane release, which could accompany global warming.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Rimmer, Susan", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: The Permian -Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuatios in Terrestrial Organic Matter", "uid": "p0000507", "west": null}, {"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; Cryosphere; Glaciers/Ice Sheet; Glaciology; Sample/Collection Description; Siple Dome; Siple Dome Ice Core; South Pole; WAISCORES", "people": "Baker, Ian; Obbard, Rachel; Sieg, Katherine", "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": "LABORATORY; FEI XL30 Environmental Scanning Electron Microscope - Field Emission Gun (ESEM - FEG); 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": "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 cores; isotopes; Nitrogen; Not provided; LABORATORY; sulfur; Mass Spectrometry; COMPUTERS; molecular; organic matter", "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": "0636767 Dunbar, Nelia; 0636740 Kreutz, Karl", "bounds_geometry": "POINT(112.11666 -79.46666)", "dataset_titles": "Microparticle, Conductivity, and Density Measurements from the WAIS Divide Deep Ice Core, Antarctica; Snowpit Chemistry - Methods Comparison, WAIS Divide, Antarctica; Snowpit evidence of the 2011 Puyehue-Cordon Caulle (Chile) eruption in West Antarctica; WAIS Divide Microparticle Concentration and Size Distribution, 0-2400 ka; WAIS Divide Snowpit Chemical and Isotope Measurements, Antarctica; WAIS Divide WDC06A Discrete ICP-MS Chemistry", "datasets": [{"dataset_uid": "609506", "doi": "10.7265/N5SJ1HHN", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Isotope; Microparticle Concentration; Snow/Ice; WAIS divide; WAIS Divide Ice Core", "people": "Kreutz, Karl; Koffman, Bess", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Snowpit Chemical and Isotope Measurements, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609506"}, {"dataset_uid": "609620", "doi": "10.7265/N5Q81B1X", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Trace Elements; WAIS divide; WAIS Divide Ice Core", "people": "Koffman, Bess; Kreutz, Karl", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Snowpit Chemistry - Methods Comparison, WAIS Divide, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609620"}, {"dataset_uid": "609616", "doi": "10.7265/N5KK98QZ", "keywords": "Antarctica; Cryosphere; Dust; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Particle Size; WAIS divide; WAIS Divide Ice Core", "people": "Kreutz, Karl; Koffman, Bess", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Microparticle Concentration and Size Distribution, 0-2400 ka", "url": "https://www.usap-dc.org/view/dataset/609616"}, {"dataset_uid": "601023", "doi": "10.15784/601023", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; ICP-MS; Isotope; WAIS divide; WAIS Divide Ice Core", "people": "Kreutz, Karl", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide WDC06A Discrete ICP-MS Chemistry", "url": "https://www.usap-dc.org/view/dataset/601023"}, {"dataset_uid": "601036", "doi": "10.15784/601036", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Geochronology; Glaciers/Ice Sheet; Ice Core Records; IntraContinental Magmatism; Snow Pit; Tephra; WAIS divide; WAIS Divide Ice Core", "people": "Koffman, Bess; Kreutz, Karl", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Snowpit evidence of the 2011 Puyehue-Cordon Caulle (Chile) eruption in West Antarctica", "url": "https://www.usap-dc.org/view/dataset/601036"}, {"dataset_uid": "609499", "doi": "10.7265/N5K07264", "keywords": "Antarctica; Cryosphere; Density; Electrical Conductivity; Glaciers/Ice Sheet; Ice Core Records; Microparticle Concentration; Physical Properties; WAIS divide; WAIS Divide Ice Core", "people": "Breton, Daniel; Hamilton, Gordon S.; Kreutz, Karl; Koffman, Bess", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Microparticle, Conductivity, and Density Measurements from the WAIS Divide Deep Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609499"}], "date_created": "Tue, 19 Jun 2012 00:00:00 GMT", "description": "This award supports a project to perform continuous microparticle concentration and size distribution measurements (using coulter counter and state-of-the-art laser detector methods), analysis of biologically relevant trace elements associated with microparticles (Fe, Zn, Co, Cd, Cu), and tephra measurements on the WAIS Divide ice core. This initial three-year project includes analysis of ice core spanning the instrumental (~1850-present) to mid- Holocene (~5000 years BP) period, with sample resolution ranging from subannual to decadal. The intellectual merit of the project is that it will help in establishing the relationships among climate, atmospheric aerosols from terrestrial and volcanic sources, ocean biogeochemistry, and greenhouse gases on several timescales which remain a fundamental problem in paleoclimatology. The atmospheric mineral dust plays an important but uncertain role in direct radiative forcing, and the microparticle datasets produced in this project will allow us to examine changes in South Pacific aerosol loading, atmospheric dynamics, and dust source area climate. The phasing of changes in aerosol properties within Antarctica, throughout the Southern Hemisphere, and globally is unclear, largely due to the limited number of annually dated records extending into the glacial period and the lack of a\u003cbr/\u003etephra framework to correlate records. The broader impacts of the proposed research are an interdisciplinary approach to climate science problems, and will contribute to several WAIS Divide science themes as well as the broader paleoclimate and oceanographic communities. Because the research topics have a large and direct societal relevance, the project will form a centerpiece of various outreach efforts at UMaine and NMT including institution websites, public speaking, local K-12 school interaction, media interviews and news releases, and popular literature. At least one PhD student and one MS student will be directly supported by this project, including fieldwork, core processing, laboratory analysis, and data interpretation/publication. We expect that one graduate student per year will apply for a core handler/assistant driller position through the WAIS Divide Science Coordination Office, and that undergraduate student involvement will result in several Capstone experience projects (a UMaine graduation requirement). Data and ideas generated from the project will be integrated into undergraduate and graduate course curricula at both institutions.", "east": 112.11666, "geometry": "POINT(112.11666 -79.46666)", "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 PROBES \u003e ELECTRON MICROPROBES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e SCANNING ELECTRON MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e LOPC-PMS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e ICE CORE MELTER; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e PARTICLE DETECTORS", "is_usap_dc": true, "keywords": "microparticle; Tephra; ice core dust; West Antarctica; Greenhouse Gases; Microparticles; Not provided; WAIS Divide-project; atmospheric dynamics; AGDC-project; Snow Pit; Ice Core Chemistry; atmospheric aerosols; Microparticles Size; LABORATORY; Ice Core Data; oxygen isotope; WAIS divide; Antarctica; FIELD SURVEYS; Ice Core; Trace Elements; FIELD INVESTIGATION; paleoclimatology; Holocene; ice cores; Isotope; AGDC; radiative forcing; Snow Chemistry", "locations": "Antarctica; WAIS divide; West Antarctica", "north": -79.46666, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Koffman, Bess; Kreutz, Karl; Breton, Daniel; Dunbar, Nelia; Hamilton, Gordon S.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.46666, "title": "Collaborative Research: Microparticle/tephra analysis of the WAIS Divide ice core", "uid": "p0000040", "west": 112.11666}, {"awards": "0537930 Steig, Eric; 0537593 White, James; 0537661 Cuffey, Kurt", "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": "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"}, {"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/"}], "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; WAIS divide; stable isotope ratios; Not provided; Ice Core; LABORATORY; FIELD SURVEYS; millennial-scale; FIELD INVESTIGATION; isotopes; Antarctica; West Antarctica; Antarctic; Ice Sheet; Deuterium", "locations": "WAIS divide; West Antarctica; Antarctic; Antarctica", "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": "Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "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": "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": "LABORATORY; biogeochemical cycles; deposition; Dust; Climate; Not provided; Climate Change; Helium Isotopes; FIELD INVESTIGATION", "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; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; Not provided", "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": "0538033 Panter, Kurt", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 14 Sep 2011 00:00:00 GMT", "description": "This project studies glaciovolcanic deposits at Minna Bluff in the western Ross Embayment of Antarctica. Its goal is to determine the history of the Ross Ice Shelf, which is fed by the major ice sheets from both East and West Antarctica. Apart from determining how these ice sheets waxed and waned during a period of dynamic climate change, glaciovolcanic sequences may constrain ice sheet parameters that are critical to numerical models such as thickness, hydrology, and basal thermal regime. This three-year study would map, analyze, and determine the age of key units using 40Ar/39Ar dating. Pilot studies would also be conducted for 36Cl dating of glacial deposits and stable isotope evaluations of alteration. The project offers a complementary record of Ross Ice Shelf behavior to that sampled by ANDRILL. It also improves the general record of McMurdo area volcanostratigraphy, which is important to interpreting landforms, glacial deposits, and ancient ice found in the Dry Valleys.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this project include improving society\u0027s understanding of global climate change, sea level rise, and graduate and undergraduate student education. Outreach efforts include educational programs for public schools and community groups, exhibits for a local science museum, and a project website.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Panter, Kurt", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Proposal: Late Cenozoic Volcanism and Glaciation at Minna Bluff, Antarctica: Implications for Antarctic Cryosphere History", "uid": "p0000252", "west": null}, {"awards": "0739598 Aydin, Murat; 0739491 Sowers, Todd", "bounds_geometry": null, "dataset_titles": "Alkanes in Firn Air Samples, Antarctica and Greenland; Methane Isotopes in South Pole Firn Air, 2008", "datasets": [{"dataset_uid": "609502", "doi": "10.7265/N55T3HFP", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; Isotope; Paleoclimate; Snow/Ice; South Pole", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": null, "title": "Methane Isotopes in South Pole Firn Air, 2008", "url": "https://www.usap-dc.org/view/dataset/609502"}, {"dataset_uid": "609504", "doi": "10.7265/N5X9287C", "keywords": "Antarctica; Arctic; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Greenland; Snow/Ice; South Pole; WAIS divide", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": null, "title": "Alkanes in Firn Air Samples, Antarctica and Greenland", "url": "https://www.usap-dc.org/view/dataset/609504"}], "date_created": "Thu, 18 Aug 2011 00:00:00 GMT", "description": "This award supports a project to make measurements of methane and other trace gases in firn air collected at South Pole, Antarctica. The analyses will include: methane isotopes (delta-13CH4 and delta-DCH4), light non-methane hydrocarbons (ethane, propane, and n-butane), sulfur gases (COS, CS2), and methyl halides (CH3Cl and CH3Br). The atmospheric burdens of these trace gases reflect changes in atmospheric OH, biomass burning, biogenic activity in terrestrial, oceanic, and wetland ecosystems, and industrial/agricultural activity. The goal of this project is to develop atmospheric histories for these trace gases over the last century through examination of depth profiles of these gases in South Pole firn air. The project will involve two phases: 1) a field campaign at South Pole, Antarctica to drill two firn holes and fill a total of ~200 flasks from depths reaching 120 m, 2) analysis of firn air at University of California, Irvine, Penn State University, and several other collaborating laboratories. Atmospheric histories will be inferred from the measurements using a one dimensional advective/diffusive model of firn air transport. This study will provide new information about the recent changes in atmospheric levels of these gases, providing about a 90 year long time series record that connects the earlier surface and firn air measurements to present day. The project will also explore the possibility of in- situ production of light non-methane hydrocarbons in firn air that is relevant to the interpretation of ice core records. The broader impacts of this research are that it has the potential for significant societal impact by improving our understanding of climate change and man\u0027s input to the atmosphere. The results of this work will be disseminated through the peer review process, and will contribute to environmental assessments, such as the Inter-governmental Panel on Climate Change (IPCC) Climate Assessment and the Word Meteorological Organization (WMO) Stratospheric Ozone Assessment. This research will provide educational opportunities for graduate and undergraduate students, and will contribute to a teacher training program for K-12 teachers in minority school districts.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GC-MS", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; Firn Air Chemistry; Firn Air Isotope Measurements; Not provided; LABORATORY; South Pole; isotopes; Firn; deltaD; Delta 13C; Carbon-13; Mass Spectrometer; Deuterium; Mass Spectrometry; Firn Air Samples; Carbon; Gas Chromatography; Polar Firn Air; GROUND-BASED OBSERVATIONS; Methane; Antarctica; Firn Air Isotopes; Delta Deuterium; FIELD SURVEYS; Firn Air; Chromatography; Methane Isotopes; Carbon Isotopes; Stable Isotopes", "locations": "Antarctica; South Pole", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Aydin, Murat; Saltzman, Eric; Sowers, Todd A.", "platforms": "Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Methane Isotopes, Hydrocarbons, and other Trace Gases in South Pole Firn Air", "uid": "p0000162", "west": null}, {"awards": "0741348 Torres, Joseph", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1002", "datasets": [{"dataset_uid": "002652", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1002", "url": "https://www.rvdata.us/search/cruise/NBP1002"}], "date_created": "Thu, 03 Mar 2011 00:00:00 GMT", "description": "Intellectual Merit: Pleuragramma antarcticum, the Antarctic silverfish, play a key role in the trophic pyramid of the Antarctic coastal ecosystem, acting as food for larger fishes, flying and non-flying seabirds, pinnipeds, and whales. In turn, they are predators on coastal euphausiids, including both Euphausia superba and crystallorophias. Historically, Pleuragramma have been an important food source for Ad\u00e9lie Penguins of the Western Antarctic Peninsula (WAP), but during the last decade Pleuragramma have disappeared from the Ad\u00e9lie diet. We suggest that Pleuragramma?s absence from the diets of top predators is linked to the declining sea ice canopy, which serves as a nursery for eggs and larvae during the austral spring. The research will investigate four hydrographic regimes over the WAP continental shelf with the following features: (1) persistent gyral flows that act to retain locally spawned larvae, (2) spring sea ice that has declined in recent years (3) the prevalence of adult silverfish, and (4) the presence of breeding Ad\u00e9lie penguins whose diets vary in the proportions of silverfish consumed. The research will evaluate the importance of local reproduction versus larval advection, and the extent to which populations in the subregions of study are genetically distinct, via analysis of population structure, otolith microchemistry and molecular genetics of fish. The Pleuragramma data will be compared with penguin diet samples taken synoptically. \u003cbr/\u003e\u003cbr/\u003eBroader Impacts: The proposed research brings together an international group of scientists with highly complimentary suites of skills to address the fate of Pleuragramma on the WAP shelf. Graduate students will use the data acquired as part of their Ph.D research, and will receive cross-training in ornithological field techniques, molecular genetic methods and otolith isotope chemistry. The PIs will work actively with the St. Petersburg Times to produce a blog in real time with pictures and text, which will be used to interact with local schools while we are at sea and after our return. The investigators also will collaborate with the COSEE center at USF and at local schools and museums to disseminate results to the K-12 community throughout the region.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Torres, Joseph", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative research: Possible climate-induced change in the distribution of Pleuragramma antarcticum on the Western Antarctic Peninsula shelf", "uid": "p0000842", "west": null}, {"awards": "0537532 Liston, Glen; 0538495 Albert, Mary; 0538416 McConnell, Joseph; 0538422 Hamilton, Gordon; 0538103 Scambos, Ted; 0963924 Steig, Eric", "bounds_geometry": "POLYGON((-180 -72.01667,-161.74667 -72.01667,-143.49334 -72.01667,-125.24001 -72.01667,-106.98668 -72.01667,-88.73335 -72.01667,-70.48002 -72.01667,-52.22669 -72.01667,-33.97336 -72.01667,-15.72003 -72.01667,2.5333 -72.01667,2.5333 -73.815003,2.5333 -75.613336,2.5333 -77.411669,2.5333 -79.210002,2.5333 -81.008335,2.5333 -82.806668,2.5333 -84.605001,2.5333 -86.403334,2.5333 -88.201667,2.5333 -90,-15.72003 -90,-33.97336 -90,-52.22669 -90,-70.48002 -90,-88.73335 -90,-106.98668 -90,-125.24001 -90,-143.49334 -90,-161.74667 -90,180 -90,162.25333 -90,144.50666 -90,126.75999 -90,109.01332 -90,91.26665 -90,73.51998 -90,55.77331 -90,38.02664 -90,20.27997 -90,2.5333 -90,2.5333 -88.201667,2.5333 -86.403334,2.5333 -84.605001,2.5333 -82.806668,2.5333 -81.008335,2.5333 -79.210002,2.5333 -77.411669,2.5333 -75.613336,2.5333 -73.815003,2.5333 -72.01667,20.27997 -72.01667,38.02664 -72.01667,55.77331 -72.01667,73.51998 -72.01667,91.26665 -72.01667,109.01332 -72.01667,126.75999 -72.01667,144.50666 -72.01667,162.25333 -72.01667,-180 -72.01667))", "dataset_titles": "Ice Core Chemistry from the Norwegian-U.S. Scientific Traverse of East Antarctica, IPY 2007-2009; Norwegian-U.S. Scientific Traverse of East Antarctica; This data set contains data from the publication Steig et al., Nature Geoscience, vol. 6, pages 372\u00e2\u20ac\u201c375 (doi:10.1038/ngeo1778), which includes isotope data from the Norway-US traverse in East Antarctica.", "datasets": [{"dataset_uid": "609520", "doi": "10.7265/N5H41PC9", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; East Antarctica; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records", "people": "McConnell, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Ice Core Chemistry from the Norwegian-U.S. Scientific Traverse of East Antarctica, IPY 2007-2009", "url": "https://www.usap-dc.org/view/dataset/609520"}, {"dataset_uid": "001305", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "This data set contains data from the publication Steig et al., Nature Geoscience, vol. 6, pages 372\u00e2\u20ac\u201c375 (doi:10.1038/ngeo1778), which includes isotope data from the Norway-US traverse in East Antarctica.", "url": "http://nsidc.org/data/nsidc-0536.html"}, {"dataset_uid": "000112", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Norwegian-U.S. Scientific Traverse of East Antarctica", "url": "http://traverse.npolar.no/"}], "date_created": "Wed, 23 Feb 2011 00:00:00 GMT", "description": "This award supports a project of scientific investigations along two overland traverses in East Antarctica: one going from the Norwegian Troll Station (72deg. S, 2deg. E) to the United States South Pole Station (90deg. S, 0deg. E) in 2007-2008; and a return traverse starting at South Pole Station and ending at Troll Station by a different route in 2008-2009. The project will investigate climate change in East Antarctica, with the goals of understanding climate variability in Dronning Maud Land of East Antarctica on time scales of years to centuries and determining the surface and net mass balance of the ice sheet in this sector to understand its impact on sea level. The project will also investigate the impact of atmospheric and oceanic variability and human activities on the chemical composition of firn and ice in the region, and will revisit areas and sites first explored by traverses in the 1960\u0027s, for detection of possible changes and to establish benchmark datasets for future research efforts. In terms of broader impacts, the results of this study will add to understanding of climate variability in East Antarctica and its contribution to global sea level change. The project includes international exchange of graduate students between the institutions involved and international education of undergraduate students through classes taught by the PI\u0027s at UNIS in Svalbard. It involves extensive outreach to the general public both in Scandinavia and North America through the press, television, science museums, children\u0027s literature, and web sites. Active knowledge sharing and collaboration between pioneers in Antarctic glaciology from Norway and the US, with the international group of scientists and students involved in this project, provide a unique opportunity to explore the changes that half a century have made in climate proxies from East Antarctica, scientific tools, and the culture and people of science. The project is relevant to the International Polar Year (IPY) since it is a genuine collaboration between nations: the scientists involved have complementary expertise, and the logistics involved relies on assets unique to each nation. It is truly an endeavor that neither nation could accomplish alone. This project is a part of the Trans- Antarctic Scientific Traverse Expeditions Ice Divide of East Antarctica (TASTE-IDEA) which is also part of IPY.", "east": 2.5333, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; 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 RADAR SOUNDERS \u003e GPR; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e PHOTOMETERS \u003e SPECTROPHOTOMETERS", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; FIXED OBSERVATION STATIONS; Glaciology; LABORATORY; FIELD SURVEYS; ice cores; Permeability; traverse; Climate Variability; Accumulation Rates; Firn; Mass Balance; Snow; Gravity; Ice Sheet; GROUND-BASED OBSERVATIONS; Not provided; Antarctic; Ice Core Chemistry; East Antarctic Plateau; Antarctica; Density", "locations": "Antarctica; Antarctic", "north": -72.01667, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Courville, Zoe; Bell, Eric; Liston, Glen; Scambos, Ted; Hamilton, Gordon S.; McConnell, Joseph; Albert, Mary R.; Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e FIXED OBSERVATION STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "NSIDC; Project website; USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Norwegian-United States IPY Scientific Traverse: Climate Variability and Glaciology in East Antarctica", "uid": "p0000095", "west": 2.5333}, {"awards": "0636705 Marchant, David; 0636731 Bender, Michael", "bounds_geometry": "POLYGON((160.48705 -77.84513,160.501913 -77.84513,160.516776 -77.84513,160.531639 -77.84513,160.546502 -77.84513,160.561365 -77.84513,160.576228 -77.84513,160.591091 -77.84513,160.605954 -77.84513,160.620817 -77.84513,160.63568 -77.84513,160.63568 -77.8515624,160.63568 -77.8579948,160.63568 -77.8644272,160.63568 -77.8708596,160.63568 -77.877292,160.63568 -77.8837244,160.63568 -77.8901568,160.63568 -77.8965892,160.63568 -77.9030216,160.63568 -77.909454,160.620817 -77.909454,160.605954 -77.909454,160.591091 -77.909454,160.576228 -77.909454,160.561365 -77.909454,160.546502 -77.909454,160.531639 -77.909454,160.516776 -77.909454,160.501913 -77.909454,160.48705 -77.909454,160.48705 -77.9030216,160.48705 -77.8965892,160.48705 -77.8901568,160.48705 -77.8837244,160.48705 -77.877292,160.48705 -77.8708596,160.48705 -77.8644272,160.48705 -77.8579948,160.48705 -77.8515624,160.48705 -77.84513))", "dataset_titles": "Dating and Paleoenvironmental Studies on Ancient Ice in the Dry Valleys, Antarctica; Measurements of Trapped Air from Mullins Valley, Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "600069", "doi": "10.15784/600069", "keywords": "Antarctica; Cryosphere; Dry Valleys; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope record; Lake Vostok; Paleoclimate", "people": "Bender, Michael", "repository": "USAP-DC", "science_program": null, "title": "Dating and Paleoenvironmental Studies on Ancient Ice in the Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600069"}, {"dataset_uid": "609597", "doi": "10.7265/N50R9MBM", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Dry Valleys; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Paleoclimate; Radar Interferometer", "people": "Bender, Michael; Yau, Audrey M.", "repository": "USAP-DC", "science_program": null, "title": "Measurements of Trapped Air from Mullins Valley, Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609597"}], "date_created": "Thu, 03 Feb 2011 00:00:00 GMT", "description": "This project studies ancient ice buried in the Dry Valleys of Antarctica. The ice, which may approach ten million years in age, will be dated using argon and uranium radioisotope techniques. High-risk work, if successful it will offer the first and perhaps only samples of the Earth\u0027s atmosphere from millions of years in the past. These samples could offer critically important tests of paleoclimate records and proxies, as well as a glimpse into the characteristics of a past world much like the predicted future, warmer Earth. The broader impacts are graduate student education, and potentially contributing to society\u0027s understanding of global climate change and sea level rise.", "east": 160.63568, "geometry": "POINT(160.561365 -77.877292)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Elemental Ratios; Not provided; Nitrogen Isotopes; LABORATORY; Argon Isotopes; FIELD INVESTIGATION; Oxygen Isotopes", "locations": null, "north": -77.84513, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Bender, Michael; Yau, Audrey M.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.909454, "title": "Collaborative Research: Dating and Paleoenvironmental Studies on Ancient Ice in the Dry Valleys, Antarctica", "uid": "p0000039", "west": 160.48705}, {"awards": "0538580 Hemming, Sidney", "bounds_geometry": "POLYGON((60 -60,72 -60,84 -60,96 -60,108 -60,120 -60,132 -60,144 -60,156 -60,168 -60,180 -60,180 -61,180 -62,180 -63,180 -64,180 -65,180 -66,180 -67,180 -68,180 -69,180 -70,168 -70,156 -70,144 -70,132 -70,120 -70,108 -70,96 -70,84 -70,72 -70,60 -70,60 -69,60 -68,60 -67,60 -66,60 -65,60 -64,60 -63,60 -62,60 -61,60 -60))", "dataset_titles": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes", "datasets": [{"dataset_uid": "600056", "doi": "10.15784/600056", "keywords": "Antarctica; Chemistry:Sediment; Geochemistry; Geochronology; isotope data; Marine Sediments; Oceans; Prydz Bay; Solid Earth; Southern Ocean; Weddell Sea; Wilkes Land", "people": "Hemming, Sidney R.; Goldstein, Steven L.; van de Flierdt, Tina", "repository": "USAP-DC", "science_program": null, "title": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes", "url": "https://www.usap-dc.org/view/dataset/600056"}], "date_created": "Sat, 20 Nov 2010 00:00:00 GMT", "description": "This project studies sediment from the ocean floor to understand Antarctica\u0027s geologic history. Glacially eroded from the Antarctic continent, these sediments may offer insight into the 99% Antarctica covered by ice. The work\u0027s central focus is determining crust formation ages and thermal histories for three key areas of East Antarctica--Prydz Bay, eastern Weddell Sea, and Wilkes Land--through a combination of petrography, bulk sediment geochemistry and radiogenic isotopes, as well as isotope chronology of individual mineral grains. One specific objective is characterizing the composition of the Gamburtsev Mountains through studies of Eocene fluvial sediments from Prydz Bay. In addition to furthering our understanding of the hidden terrains of Antarctica, these terrigenous sediments will also serve as a natural laboratory to evaluate the effects of continental weathering on the Hf/Nd isotope systematics of seawater. An important broader impact of the project is providing exciting research projects for graduate and postdoctoral students using state of the art techniques in geochemistry.", "east": 180.0, "geometry": "POINT(120 -65)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Van De Flierdt, Christina-Maria; Goldstein, Steven L.; Hemming, Sidney R.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes", "uid": "p0000524", "west": 60.0}, {"awards": "0439906 Koch, Paul", "bounds_geometry": "POLYGON((162 -72,162.6 -72,163.2 -72,163.8 -72,164.4 -72,165 -72,165.6 -72,166.2 -72,166.8 -72,167.4 -72,168 -72,168 -72.6,168 -73.2,168 -73.8,168 -74.4,168 -75,168 -75.6,168 -76.2,168 -76.8,168 -77.4,168 -78,167.4 -78,166.8 -78,166.2 -78,165.6 -78,165 -78,164.4 -78,163.8 -78,163.2 -78,162.6 -78,162 -78,162 -77.4,162 -76.8,162 -76.2,162 -75.6,162 -75,162 -74.4,162 -73.8,162 -73.2,162 -72.6,162 -72))", "dataset_titles": "Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change", "datasets": [{"dataset_uid": "600041", "doi": "10.15784/600041", "keywords": "Biology; Biosphere; Isotope; Penguin; Ross Sea; Seals; Southern Ocean", "people": "Koch, Paul", "repository": "USAP-DC", "science_program": null, "title": "Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change", "url": "https://www.usap-dc.org/view/dataset/600041"}], "date_created": "Sat, 30 Oct 2010 00:00:00 GMT", "description": "During previous NSF-sponsored research, the PI\u0027s discovered that southern elephant seal colonies once existed along the Victoria Land coast (VLC) of Antarctica, a region where they are no longer observed. Molted seal skin and hair occur along 300 km of coastline, more than 1000 km from any extant colony. The last record of a seal at a former colony site is at ~A.D. 1600. Because abandonment occurred prior to subantarctic sealing, disappearance of the VLC colony probably was due to environmental factors, possibly cooling and encroachment of land-fast, perennial sea ice that made access to haul-out sites difficult. The record of seal inhabitation along the VLC, therefore, has potential as a proxy for climate change. Elephant seals are a predominantly subantarctic species with circumpolar distribution. Genetic studies have revealed significant differentiation among populations, particularly with regard to that at Macquarie I., which is the extant population nearest to the abandoned VLC colony. Not only is the Macquarie population unique genetically, but it is has undergone unexplained decline of 2%/yr over the last 50 years3. In a pilot study, genetic analyses showed a close relationship between the VLC seals and those at Macquarie I. An understanding of the relationship between the two populations, as well as of the environmental pressures that led to the demise of the VLC colonies, will provide a better understanding of present-day population genetic structure, the effect of environmental change on seal populations, and possibly the reasons underlying the modern decline at Macquarie Island.\u003cbr/\u003eThis project addresses several key research problems: (1) Why did elephant seals colonize and then abandon the VLC? (2) What does the elephant seal record reveal about Holocene climate change and sea-ice conditions? (3) What were the foraging strategies of the seals and did these strategies change over time as climate varied? (4) How does the genetic structure of the VLC seals relate to extant populations? (5) How did genetic diversity change over time and with colony decline? (6) Using ancient samples to estimate mtDNA mutation rates, what can be learned about VLC population dynamics over time? (7) What was the ecological relationship between elephant seals and Adelie penguins that occupied the same sites, but apparently at different times? The proposed work includes the professional training of young researchers and incorporation of data into graduate and undergraduate courses.", "east": 168.0, "geometry": "POINT(165 -75)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS", "locations": null, "north": -72.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Koch, Paul", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change", "uid": "p0000533", "west": 162.0}, {"awards": "0636506 Mayewski, Paul", "bounds_geometry": "POLYGON((-137.7 -75.7,-137.4 -75.7,-137.1 -75.7,-136.8 -75.7,-136.5 -75.7,-136.2 -75.7,-135.9 -75.7,-135.6 -75.7,-135.3 -75.7,-135 -75.7,-134.7 -75.7,-134.7 -75.773,-134.7 -75.846,-134.7 -75.919,-134.7 -75.992,-134.7 -76.065,-134.7 -76.138,-134.7 -76.211,-134.7 -76.284,-134.7 -76.357,-134.7 -76.43,-135 -76.43,-135.3 -76.43,-135.6 -76.43,-135.9 -76.43,-136.2 -76.43,-136.5 -76.43,-136.8 -76.43,-137.1 -76.43,-137.4 -76.43,-137.7 -76.43,-137.7 -76.357,-137.7 -76.284,-137.7 -76.211,-137.7 -76.138,-137.7 -76.065,-137.7 -75.992,-137.7 -75.919,-137.7 -75.846,-137.7 -75.773,-137.7 -75.7))", "dataset_titles": "Ion Concentrations from SPRESSO Ice Core, Antarctica; Mt. Moulton Ice Trench Mass Spectrometry Data, Antarctica", "datasets": [{"dataset_uid": "609472", "doi": "10.7265/N5VH5KSV", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Mt Moulton; Paleoclimate", "people": "Mayewski, Paul A.; Korotkikh, Elena", "repository": "USAP-DC", "science_program": null, "title": "Mt. Moulton Ice Trench Mass Spectrometry Data, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609472"}, {"dataset_uid": "609471", "doi": "10.7265/N508638J", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; ITASE; Paleoclimate; South Pole; SPRESSO Ice Core", "people": "Korotkikh, Elena; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": null, "title": "Ion Concentrations from SPRESSO Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609471"}], "date_created": "Thu, 29 Jul 2010 00:00:00 GMT", "description": "This award supports a project to examine an existing ice core of opportunity from South Pole (SPRESO core) to develop a 2000+ year long climate record. SPRESO ice core will be an annually dated, sub-annually-resolved reconstruction of past climate (atmospheric circulation, temperature, precipitation rate, and atmospheric chemistry) utilizing continuous, co-registered measurements (n=45) of: major ions, trace elements, and stable isotope series, plus selected sections for microparticle size and composition. The intellectual merit of this project relates to the fact that few 2000+ year records of this quality exist in Antarctica despite increasing scientific interest in this critical time period as the framework within which to understand modern climate. The scientific impact of this ice core investigation are that it will provide an in-depth understanding of climate variability; a baseline for assessing modern climate variability in the context of human activity; and a contribution to the prediction of future climate variability. The broader impact of this work is that the proposed research addresses important questions concerning the role of Antarctica in past, present, and future global change. Results will be translated into publicly accessible information through public lectures, media appearances, and an extensive outreach activity housed in our Institute. Our ice core activities provide a major basis for curriculum in K-12 and University plus a basis for several field and laboratory based graduate theses and undergraduate student projects. The project will support one PhD student for 3 years and undergraduate salaries. The Climate Change Institute has a long history of gender and ethnically diverse student and staff involvement in research.", "east": -134.7, "geometry": "POINT(-136.2 -76.065)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Ice Core Interpretation; Ions; US ITASE; LABORATORY; EXPLORATIONS; Ice Core Data; Ice Core; Ice Analysis; Ice; Not provided; Antarctic Ice Sheet; ice chemistry; ice cores; Laboratory investigations; Field Investigations; Ice Core Chemistry; Horizontal Ice Core; Ice Sheet", "locations": "Antarctic Ice Sheet", "north": -75.7, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Korotkikh, Elena; Kreutz, Karl; Kurbatov, Andrei V.; Mayewski, Paul A.", "platforms": "Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.43, "title": "Collaborative Proposal: 2000+ Year Detailed, Calibrated Climate Reconstruction from a South Pole Ice Core Set in an Antarctic - Global Scale Context", "uid": "p0000209", "west": -137.7}, {"awards": "0538657 Severinghaus, Jeffrey", "bounds_geometry": null, "dataset_titles": "Borehole Temperature Measurement in WDC05A in January 2008 and January 2009; Low-res d15N and d18O of O2 in the WAIS Divide 06A Deep Core; Ultra-High Resolution LA-ICP-MS Results: DO-21 Rapid Warming Event; WAIS Divide d18Oatm and Siple Dome/WAIS Divide composite and individual delta epsilon LAND", "datasets": [{"dataset_uid": "609637", "doi": "10.7265/N5B27S7S", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Temperature; WAIS divide; WAIS Divide Ice Core", "people": "Severinghaus, Jeffrey P.; Orsi, Anais J.", "repository": "USAP-DC", "science_program": null, "title": "Borehole Temperature Measurement in WDC05A in January 2008 and January 2009", "url": "https://www.usap-dc.org/view/dataset/609637"}, {"dataset_uid": "601041", "doi": "10.15784/601041", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Gas; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; WAIS Divide Ice Core", "people": "Seltzer, Alan; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide d18Oatm and Siple Dome/WAIS Divide composite and individual delta epsilon LAND", "url": "https://www.usap-dc.org/view/dataset/601041"}, {"dataset_uid": "609660", "doi": "10.7265/N5S46PWD", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; WAIS divide; WAIS Divide Ice Core", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Low-res d15N and d18O of O2 in the WAIS Divide 06A Deep Core", "url": "https://www.usap-dc.org/view/dataset/609660"}, {"dataset_uid": "609635", "doi": "10.7265/N51J97PS", "keywords": "Arctic; Cryosphere; Geochemistry; GISP; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate", "people": "Haines, Skylar; Kurbatov, Andrei V.; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": null, "title": "Ultra-High Resolution LA-ICP-MS Results: DO-21 Rapid Warming Event", "url": "https://www.usap-dc.org/view/dataset/609635"}], "date_created": "Thu, 08 Jul 2010 00:00:00 GMT", "description": "0538657\u003cbr/\u003eSeveringhaus\u003cbr/\u003eThis award supports a project to develop high-resolution (20-yr) nitrogen and oxygen isotope records on trapped gases in the WAIS Divide ice core (Antarctica), with a comparison record for chronological purposes in the GISP2 (Greenland) ice core. The main scientific objective is to provide an independent temperature-change record for the past 100,000 years in West Antarctica that is not subject to the uncertainty inherent in ice isotopes (18O and deuterium), the classical paleothermometer. Nitrogen isotopes (Delta 15N) in air bubbles in glacial ice record rapid surface temperature change because of thermal fractionation of air in the porous firn layer, and this isotopic anomaly is recorded in bubbles as the firn becomes ice. Using this gas-based temperature-change record, in combination with methane data as interpolar stratigraphic markers, the proposed work will define the precise relative timing of abrupt warming in Greenland and abrupt cooling at the WAIS Divide site during the millennial-scale climatic oscillations of Marine Isotopic Stage 3 (30-70 kyr BP) and the last glacial termination. The nitrogen isotope record also provides constraints on past firn thickness, which inform temperature and accumulation rate histories from the ice core. A search for possible solar-related cycles will be conducted with the WAIS Divide Holocene (Delta 15N.) Oxygen isotopes of O2 (Delta 18Oatm) are obtained as a byproduct of the (Delta 15N) measurement. The gas-isotopic records will enhance the value of other atmospheric gas measurements in WAIS Divide, which are expected to be of unprecedented quality. The high-resolution (Delta 18Oatm) records will provide chronological control for use by the international ice coring community and for surface glacier ice dating. Education of a graduate student, and training of a staff member in the laboratory, will contribute to the nation\u0027s human resource base. Outreach activities in the context of the International Polar Year will be enhanced. International collaboration is planned with the laboratory of LSCE, University of Paris.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e LA-ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "NSIDC; LABORATORY; WAIS Divide-project; Depth; Not provided; GROUND-BASED OBSERVATIONS; WAIS divide; AGDC; AGDC-project; Borehole Temperatures; Ice Core", "locations": "WAIS divide", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Haines, Skylar; Mayewski, Paul A.; Orsi, Anais J.; Kurbatov, Andrei V.; Severinghaus, Jeffrey P.", "platforms": "Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": null, "title": "Nitrogen and Oxygen Gas Isotopes in the WAIS Divide Ice Core as Constraints on Chronology, Temperature, and Accumulation Rate", "uid": "p0000036", "west": null}, {"awards": "9614844 Jeffries, Martin", "bounds_geometry": "POLYGON((-180 -43.56557,-144 -43.56557,-108 -43.56557,-72 -43.56557,-36 -43.56557,0 -43.56557,36 -43.56557,72 -43.56557,108 -43.56557,144 -43.56557,180 -43.56557,180 -46.996716,180 -50.427862,180 -53.859008,180 -57.290154,180 -60.7213,180 -64.152446,180 -67.583592,180 -71.014738,180 -74.445884,180 -77.87703,144 -77.87703,108 -77.87703,72 -77.87703,36 -77.87703,0 -77.87703,-36 -77.87703,-72 -77.87703,-108 -77.87703,-144 -77.87703,-180 -77.87703,-180 -74.445884,-180 -71.014738,-180 -67.583592,-180 -64.152446,-180 -60.7213,-180 -57.290154,-180 -53.859008,-180 -50.427862,-180 -46.996716,-180 -43.56557))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002003", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9901"}, {"dataset_uid": "002110", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9803"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is a study of the effects of antarctic sea ice in the global climate system, through an examination of how the spatial distribution of ice and snow thickness and of open water is reflected in satellite-based synthetic aperture radar (SAR) imagery. The field investigations will be carried out from the RVIB Nathaniel B. Palmer in winter 1998 and summer 1999, and will produce observations of the snow and ice distribution, the crystal structure, stable isotopes, salinity and temperature structure of ice cores, and the stratigraphy, grain size, and water content of the snow cover. The SAR images from ERS-2 and RADARSAT will be acquired at the McMurdo ground station, and processed at the Alaska SAR Facility. These will provide information about the large-scale ice motion field and the small-scale ice deformation field, both of which contribute to the observed ice thickness distribution. In addition, a study of the spatial and temporal variation of the backscattered microwave energy will contribute to the development of numerical models that simulate the dynamic and thermodynamic interactions among the sea ice, ocean, and atmosphere. The surface data is vital for the extraction of environmental information from the radar data, and for the ultimate validation of interactive models.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56557, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jeffries, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.87703, "title": "Dynamic/Thermodynamic Processes and Their Contribution to the Sea Ice Thickness Distribution and Radar Backscatter in the Ross Sea", "uid": "p0000628", "west": -180.0}, {"awards": "9316035 Gowing, Marcia", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP9406", "datasets": [{"dataset_uid": "002592", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP9406", "url": "https://www.rvdata.us/search/cruise/NBP9406"}, {"dataset_uid": "002252", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9406"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. The focus of this proposal is the role of microzooplankton in controlling the production and fate of carbon during the two types of blooms. Objectives are: 1) to determine biomass, abundance, size and selected species composition of primary producer assemblages, 2) to determine similar features of nano- and microplanktonic heterotrophic assemblages, 3) to measure total community grazing on heterotrophic bacteria and phytoplankton, 4) to examine which grazers are the major herbivores and bacterivores, and 5) to measure the contribution of microzooplankton and mesozooplankton egesta, sinking of algal cells and colonies, and sinking of protozoan assemblages associated with detritus to the total carbon flux from the euphotic zone through 250 m depth. Water samples for abundance and biomass determinations will be taken and samples will be examined with epifluorescence microscopy. Grazing rates will be measured using the dilution grazing technique and the dual-isotope radiolabeling single cell method. Carbon fluxes will be determined on sinking material collected with particle interceptor traps at the base of the euphotic zone and two deeper depths, using microscopical analysis . An understanding of these processes and other fundamental processes studied by collaborating investigators will contribute to the understanding of the role of the Southern Ocean in present, past and predicted future sequestration of carbon, as well as in other global elemental cycles.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Bloom Dynamics and Food Web Structure in the Ross Sea: Role of Microzooplankton in Controlling Production", "uid": "p0000811", "west": null}, {"awards": "9317588 Lawver, Lawrence", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP9507", "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"}, {"dataset_uid": "002590", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP9507", "url": "https://www.rvdata.us/search/cruise/NBP9507"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award supports a marine geophysical investigation of the Bransfield Strait and the Shackleton Fracture Zone and environs in the Scotia Sea in an effort to understand the neotectonic evolution of the region. Multibeam swath mapping and sidescan sonar mapping will be used along with multichannel seismic imaging. The main goal of this proposal is to collect multibeam and sidescan sonar data to map the structural character and tectonic fabric of the evolving plate boundary in Southwest Scotia Sea, Shackleton Fracture Zone, and Bransfield Strait. Follow up multichannel seismic surveys will be done in the Southwest Scotia Sea. The secondary goal is to use sidescan sonar reflectivity images to generate detailed structural maps of the seafloor of these regions and to integrate the new data with existing seismic reflection, Geosat gravity, Hydrosweep and Seabeam bathymetric data. Once the base maps are produced they can be used by other researchers to help interpret multichannel and single channel seismic reflection records. The neotectonic evolution of the Antarctic Peninsula and Scotia Sea is extremely complex. Understanding the recent evolution of the Drake-Scotia-Antarctic-South America plate intersections will provide important information as to how major plate boundaries reorganize after demise of a long-lived spreading center and the consequential reduction in the number of plates. The plate reorganization probably resulted in the uplift of the Shackleton Ridge which may have effected the sedimentary patterns in both the Scotia Sea and possibly the Weddell Sea. If the break of the Shackleton transform fault can be traced with multibeam and sidescan sonar as it intersects the southern end of South America then the orientation and geometry of the faults, fractures and deformation as the transform fault intersects the South American continent will help to interpret the structures in that complex region. Bransfield Strait is presently undergoing extensi on based on high heat flow, active volcanoes and inferences from seismic reflection work. Seismic refraction indicates thick crust similar to the East African Rift or passive volcanic margins of continents. In contrast, analysis of isotopes and rare earth elements of the recent volcanics shows seemingly no continental contamination. The active extension in Bransfield Strait must be related to the plate reorganization but it is unclear exactly what tectonic processes are occurring. Besides elucidating the tectonic fabric of Bransfield Strait, the multibeam and sidescan sonar survey will identify potential dredge targets and DSRV Alvin dive sites.", "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": "Klinkhammer, Gary", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Neotectonic Evolution of Antarctic Peninsula/Scotia Sea Region: Multi-Beam, Sidescan Sonar, Seismic, Magnetics and Gravity Studies", "uid": "p0000809", "west": null}, {"awards": "0732995 Barbeau, David", "bounds_geometry": "POLYGON((-67.9988 -52.7596,-66.83756 -52.7596,-65.67632 -52.7596,-64.51508 -52.7596,-63.35384 -52.7596,-62.1926 -52.7596,-61.03136 -52.7596,-59.87012 -52.7596,-58.70888 -52.7596,-57.54764 -52.7596,-56.3864 -52.7596,-56.3864 -54.15258,-56.3864 -55.54556,-56.3864 -56.93854,-56.3864 -58.33152,-56.3864 -59.7245,-56.3864 -61.11748,-56.3864 -62.51046,-56.3864 -63.90344,-56.3864 -65.29642,-56.3864 -66.6894,-57.54764 -66.6894,-58.70888 -66.6894,-59.87012 -66.6894,-61.03136 -66.6894,-62.1926 -66.6894,-63.35384 -66.6894,-64.51508 -66.6894,-65.67632 -66.6894,-66.83756 -66.6894,-67.9988 -66.6894,-67.9988 -65.29642,-67.9988 -63.90344,-67.9988 -62.51046,-67.9988 -61.11748,-67.9988 -59.7245,-67.9988 -58.33152,-67.9988 -56.93854,-67.9988 -55.54556,-67.9988 -54.15258,-67.9988 -52.7596))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001520", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0717"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project studies the relationship between opening of the Drake Passage and formation of the Antarctic ice sheet. Its goal is to answer the question: What drove the transition from a greenhouse to icehouse world thirty-four million years ago? Was it changes in circulation of the Southern Ocean caused by the separation of Antarctica from South America or was it a global effect such as decreasing atmospheric CO2 content? This study constrains the events and timing through fieldwork in South America and Antarctica and new work on marine sediment cores previously collected by the Ocean Drilling Program. It also involves an extensive, multidisciplinary analytical program. Compositional analyses of sediments and their sources will be combined with (U-Th)/He, fission-track, and Ar-Ar thermochronometry to constrain uplift and motion of the continental crust bounding the Drake Passage. Radiogenic isotope studies of fossil fish teeth found in marine sediment cores will be used to trace penetration of Pacific seawater into the Atlantic. Oxygen isotope and trace metal measurements on foraminifera will provide additional information on the timing and magnitude of ice volume changes. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eThe broader impacts include graduate and undergraduate education; outreach to the general public through museum exhibits and presentations, and international collaboration with scientists from Argentina, Ukraine, UK and Germany.\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eThe project is supported under NSF\u0027s International Polar Year (IPY) research emphasis area on \"Understanding Environmental Change in Polar Regions\". This project is also a key component of the IPY Plates \u0026 Gates initiative (IPY Project #77), focused on determining the role of tectonic gateways in instigating polar environmental change.", "east": -56.3864, "geometry": "POINT(-62.1926 -59.7245)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.7596, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "MacPhee, Ross", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -66.6894, "title": "Collaborative Research: IPY: Testing the Polar Gateway Hypothesis: An Integrated Record of Drake Passage Opening \u0026 Antarctic Glaciation", "uid": "p0000120", "west": -67.9988}, {"awards": "0636639 MacPhee, Ross", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG0717; Expedition data of LMG0902", "datasets": [{"dataset_uid": "001520", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0717"}, {"dataset_uid": "002677", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0717", "url": "https://www.rvdata.us/search/cruise/LMG0717"}, {"dataset_uid": "002727", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0902", "url": "https://www.rvdata.us/search/cruise/LMG0902"}, {"dataset_uid": "002669", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0902", "url": "https://www.rvdata.us/search/cruise/LMG0902"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This exploratory project searches for fossils on Livingston Island in the South Shetland Islands off of the Antarctic peninsula. Strata there date from 125 to 99 million years in age, a critical time in the development of various flora and fauna. With so many unknowns in the biotic history of the Antarctic, any finds of vertebrate fossils on this little explored island will be of great significance. One key question is marsupial evolution. It is assumed that marsupials of South America and Australia transited through Antarctica, but a supporting fossil record has yet to be discovered. Related investigations on Mesozoic climate will be performed through stable isotope analysis of clay and rock samples. The broader impacts of the project include graduate student education and public outreach through a museum exhibit.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "MacPhee, Ross; DeMaster, David", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Vertebrate Paleontology of Livingston Island, South Shetlands, Antarctica", "uid": "p0000858", "west": null}, {"awards": "9316767 Jeffries, Martin", "bounds_geometry": "POLYGON((-180 -43.56571,-144 -43.56571,-108 -43.56571,-72 -43.56571,-36 -43.56571,0 -43.56571,36 -43.56571,72 -43.56571,108 -43.56571,144 -43.56571,180 -43.56571,180 -46.304308,180 -49.042906,180 -51.781504,180 -54.520102,180 -57.2587,180 -59.997298,180 -62.735896,180 -65.474494,180 -68.213092,180 -70.95169,144 -70.95169,108 -70.95169,72 -70.95169,36 -70.95169,0 -70.95169,-36 -70.95169,-72 -70.95169,-108 -70.95169,-144 -70.95169,-180 -70.95169,-180 -68.213092,-180 -65.474494,-180 -62.735896,-180 -59.997298,-180 -57.2587,-180 -54.520102,-180 -51.781504,-180 -49.042906,-180 -46.304308,-180 -43.56571))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002234", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9503"}, {"dataset_uid": "002231", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9505"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The goal of this investigation is to understand the role of snow in sea ice development processes and air-ice-ocean heat exchange interactions in the seasonal and perennial sea ice zones of the Ross Sea, the Amundsen Sea, and the Bellingshausen Sea. Observations and measurements of the characteristics of sea ice and snow will be combined with numerical models of sea-ice flooding and the entrainment of snow into the ice cover in order to gain an understanding of the sea-ice heat and mass balance, and to quantify the energy exchange within the antarctic sea-ice cover. The snow measurement program, using the RVIB Nathaniel B. Palmer, will include depth, grain size and morphology, density, temperature, thermal conductivity, water content, and stable isotope ratio. The ice measurement program will include thickness, salinity, temperature, density, brine content, and included gas volume, as well as such structural properties as the fraction of frazil, platelet, and congelation ice in the seasonal antarctic pack ice. Differences in ice types are the result of differences in the environment in which the ice forms: frazil ice is formed in supercooled sea water, normally through wind or wave-induced turbulence, while platelet and congelation ice is formed under quiescent conditions. The fraction of frazil ice is an important variable in the energy budget of the upper ocean, and contributes significantly to the stabilization of the surface layers. The numerical models will involve the thermodynamics of phase changes from liquid water to ice, along with the resulting energy transfer, brine expulsion, and the modulating effect of a snow cover. The results are expected to have broad relevance and application to understanding the effects of sea-ice processes in global change, and atmospheric, oceanographic, and remote sensing investigations of the Southern Ocean.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56571, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jeffries, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -70.95169, "title": "The Role of Snow in Antarctic Sea Ice Development and Ocean-Atmosphere Energy Exchange", "uid": "p0000642", "west": -180.0}, {"awards": "9317379 Foster, Theodore", "bounds_geometry": "POLYGON((143.4953 -43.56287,146.46757 -43.56287,149.43984 -43.56287,152.41211 -43.56287,155.38438 -43.56287,158.35665 -43.56287,161.32892 -43.56287,164.30119 -43.56287,167.27346 -43.56287,170.24573 -43.56287,173.218 -43.56287,173.218 -46.238515,173.218 -48.91416,173.218 -51.589805,173.218 -54.26545,173.218 -56.941095,173.218 -59.61674,173.218 -62.292385,173.218 -64.96803,173.218 -67.643675,173.218 -70.31932,170.24573 -70.31932,167.27346 -70.31932,164.30119 -70.31932,161.32892 -70.31932,158.35665 -70.31932,155.38438 -70.31932,152.41211 -70.31932,149.43984 -70.31932,146.46757 -70.31932,143.4953 -70.31932,143.4953 -67.643675,143.4953 -64.96803,143.4953 -62.292385,143.4953 -59.61674,143.4953 -56.941095,143.4953 -54.26545,143.4953 -51.589805,143.4953 -48.91416,143.4953 -46.238515,143.4953 -43.56287))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002240", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9502"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9317379 Foster This project is study of the deep and bottom water formation processes of the antarctic continental shelf off Wilkes Land between 145 deg E longitude and 160 deg E longitude. The project is to be carried out jointly with an Australian oceanographic project. Preliminary work in 1985 has shown that hydrographic sections in this area are quite similar to those of known deep water formation regions in the southern Weddell Sea. This project will include the year-long deployment of six current meter moorings, and tracer studies (oxygen, carbon dioxide, chlorofluorocarbons, stable isotopes, and nutrients) to test whether shelf waves and tides are the principal mechanism for mixing shelf water with the off-shore intermediate water. Two oceanographic cruises are planned for this work: a cruise of the RVIB Nathaniel B. Palmer in February 1995, and a cruise of the Australian ship R/V Aurora Australis in February 1996. ***", "east": 173.218, "geometry": "POINT(158.35665 -56.941095)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56287, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Foster, Theodore; Foster, Ted", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -70.31932, "title": "Deep Water Formation off the Eastern Wilkes Land Coast of Antarctica", "uid": "p0000645", "west": 143.4953}, {"awards": "0444134 Mitchell, B. Gregory", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0606", "datasets": [{"dataset_uid": "002646", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0606", "url": "https://www.rvdata.us/search/cruise/NBP0606"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The Shackleton Fracture Zone (SFZ) in Drake Passage of the Southern Ocean defines a boundary between low and high phytoplankton waters. Low chlorophyll water flowing through the southern Drake Passage emerges as high chlorophyll water to the east, and recent evidence indicates that the Southern Antarctic Circumpolar Current Front (SACCF) is steered south of the SFZ onto the Antarctic Peninsula shelf where mixing between the water types occurs. The mixed water is then advected off-shelf with elevated iron and phytoplankton biomass. The SFZ is therefore an ideal natural laboratory to improve the understanding of plankton community responses to natural iron fertilization, and how these processes influence export of organic carbon to the ocean interior. The bathymetry of the region is hypothesized to influence mesoscale circulation and transport of iron, leading to the observed patterns in phytoplankton biomass. The position of the Antarctic Circumpolar Current (ACC) is further hypothesized to influence the magnitude of the flow of ACC water onto the peninsula shelf, mediating the amount of iron transported into the Scotia Sea. To address these hypotheses, a research cruise will be conducted near the SFZ and to the east in the southern Scotia Sea. A mesoscale station grid for vertical profiles, water sampling, and bottle incubation enrichment experiments will complement rapid surface surveys of chemical, plankton, and hydrographic properties. Distributions of manganese, aluminum and radium isotopes will be determined to trace iron sources and estimate mixing rates. Phytoplankton and bacterial physiological states (including responses to iron enrichment) and the structure of the plankton communities will be studied. The primary goal is to better understand how plankton productivity, community structure and export production in the Southern Ocean are affected by the coupling between bathymetry, mesoscale circulation, and distributions of limiting nutrients. The proposed work represents an interdisciplinary approach to address the fundamental physical, chemical and biological processes that contribute to the abrupt transition in chl-a which occurs near the SFZ. Given recent indications that the Southern Ocean is warming, it is important to advance the understanding of conditions that regulate the present ecosystem structure in order to predict the effects of climate variability. This project will promote training and learning across a broad spectrum of groups. Funds are included to support postdocs, graduate students, and undergraduates. In addition, this project will contribute to the development of content for the Polar Science Station website, which has been a resource since 2001 for instructors and students in adult education, home schooling, tribal schools, corrections education, family literacy programs, and the general public.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Mitchell, B.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Plankton Community Structure and Iron Distribution in the Southern Drake Passage and Scotia Sea", "uid": "p0000837", "west": null}, {"awards": "0837988 Steig, Eric", "bounds_geometry": "POLYGON((-180 -65,-144 -65,-108 -65,-72 -65,-36 -65,0 -65,36 -65,72 -65,108 -65,144 -65,180 -65,180 -67.5,180 -70,180 -72.5,180 -75,180 -77.5,180 -80,180 -82.5,180 -85,180 -87.5,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.5,-180 -85,-180 -82.5,-180 -80,-180 -77.5,-180 -75,-180 -72.5,-180 -70,-180 -67.5,-180 -65))", "dataset_titles": "West Antarctica Ice Core and Climate Model Data", "datasets": [{"dataset_uid": "609536", "doi": "10.7265/N5QJ7F8B", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; WAIS divide", "people": "Steig, Eric J.", "repository": "USAP-DC", "science_program": null, "title": "West Antarctica Ice Core and Climate Model Data", "url": "https://www.usap-dc.org/view/dataset/609536"}], "date_created": "Fri, 30 Apr 2010 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). \u003cbr/\u003e\u003cbr/\u003eThis award supports a project to reconstruct the past physical and chemical climate of Antarctica, with an emphasis on the region surrounding the Ross Sea Embayment, using \u003e60 ice cores collected in this region by US ITASE and by Australian, Brazilian, Chilean, and New Zealand ITASE teams. The ice core records are annually resolved and exceptionally well dated, and will provide, through the analyses of stable isotopes, major soluble ions and for some trace elements, instrumentally calibrated proxies for past temperature, precipitation, atmospheric circulation, chemistry of the atmosphere, sea ice extent, and volcanic activity. These records will be used to understand the role of solar, volcanic, and human forcing on Antarctic climate and to investigate the character of recent abrupt climate change over Antarctica in the context of broader Southern Hemisphere and global climate variability. The intellectual merit of the project is that ITASE has resulted in an array of ice core records, increasing the spatial resolution of observations of recent Antarctic climate variability by more than an order of magnitude and provides the basis for assessment of past and current change and establishes a framework for monitoring of future climate change in the Southern Hemisphere. This comes at a critical time as global record warming and other impacts are noted in the Southern Ocean, the Antarctic Peninsula, and on the Antarctic ice sheet. The broader impacts of the project are that Post-doctoral and graduate students involved in the project will benefit from exposure to observational and modeling approaches to climate change research and working meetings to be held at the two collaborating institutions plus other prominent climate change institutions. The results are of prime interest to the public and the media Websites hosted by the two collaborating institutions contain climate change position papers, scientific exchanges concerning current climate change issues, and scientific contribution series.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Deuterium Isotopes; Deuterium Excess; Not provided; WAIS Divide-project; GROUND-BASED OBSERVATIONS; AGDC-project", "locations": null, "north": -65.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "Not provided; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Antarctic Climate Reconstruction Utilizing the US ITASE Ice Core Array (2009- 2012)", "uid": "p0000180", "west": -180.0}, {"awards": "0520523 Brook, Edward J.", "bounds_geometry": null, "dataset_titles": "Methane Measurements from the GISP2 and Siple Dome Ice Cores", "datasets": [{"dataset_uid": "609440", "doi": "10.7265/N58P5XFZ", "keywords": "Antarctica; Arctic; Chemistry:Fluid; Cryosphere; Geochemistry; GISP2; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Methane Measurements from the GISP2 and Siple Dome Ice Cores", "url": "https://www.usap-dc.org/view/dataset/609440"}], "date_created": "Wed, 09 Dec 2009 00:00:00 GMT", "description": "Not Available", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Methane; Greenland Ice Cap; Ice Core Data; Siple Dome; Not provided; Ice Core Gas Records; DRILLING PLATFORMS; LABORATORY; Ice Core; Ice Core Chemistry; Antarctica; Greenland Ice Sheet Project 2", "locations": "Antarctica; Greenland Ice Cap; Siple Dome", "north": null, "nsf_funding_programs": "Arctic Natural Sciences", "paleo_time": null, "persons": "Brook, Edward J.", "platforms": "WATER-BASED PLATFORMS \u003e FIXED PLATFORMS \u003e SURFACE \u003e DRILLING PLATFORMS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Collaborative Research: New insights into the Holocene methane budget from dual isotope systematics and a high resolution record of the interpolar gradient", "uid": "p0000131", "west": null}, {"awards": "0196105 Steig, Eric", "bounds_geometry": null, "dataset_titles": "US ITASE Stable Isotope Data, Antarctica", "datasets": [{"dataset_uid": "609425", "doi": "10.7265/N5NZ85MD", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Isotope; ITASE; Paleoclimate; WAIS", "people": "Steig, Eric J.", "repository": "USAP-DC", "science_program": "ITASE", "title": "US ITASE Stable Isotope Data, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609425"}], "date_created": "Thu, 01 Oct 2009 00:00:00 GMT", "description": "Not Available", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e AMS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e LIDAR/LASER SPECTROMETERS \u003e PALMS", "is_usap_dc": true, "keywords": "Isotope; Depth; Ice Core Gas Records; Ice Core; Ice Core Data; Ice Core Chemistry; LABORATORY; Firn Isotopes; FIELD SURVEYS; Oxygen Isotopes; Deuterium; Ice Age; Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ITASE", "south": null, "title": "Stable Isotope Studies at West Antarctic ITASE Sites", "uid": "p0000013", "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; 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": "0440975 Severinghaus, Jeffrey", "bounds_geometry": "POINT(-119.533333 -80.016667)", "dataset_titles": "Nitrogen and Oxygen Gas Isotopes in the Siple Dome and Byrd Ice Cores, Antarctica", "datasets": [{"dataset_uid": "609407", "doi": "10.7265/N55X26V0", "keywords": "Antarctica; Arctic; Atmosphere; Byrd Glacier; Byrd Ice Core; Chemistry:Fluid; Cryosphere; Geochemistry; GISP2; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Nitrogen and Oxygen Gas Isotopes in the Siple Dome and Byrd Ice Cores, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609407"}], "date_created": "Fri, 17 Jul 2009 00:00:00 GMT", "description": "The award supports the development of high-resolution nitrogen and oxygen isotope records on trapped gases in the Byrd and Siple Dome ice cores, and the Holocene part of the GISP2 ice core. The primary scientific goals of this work are to understand the enigmatic d15N anomalies seen thus far in the Siple Dome record at 15.3 ka and 35 ka, and to find other events that may occur in both cores. At these events, d15N of trapped air approaches zero, implying little or no gravitational fractionation of gases in the firn layer at the time of formation of the ice. These events may represent times of low accumulation rate and arid meteorological conditions, and thus may contain valuable information about the climatic history of West Antarctica. Alternatively, they may stem from crevassing and thus may reveal ice-dynamical processes. Finding the events in the Byrd core, which is located 500 km from Siple Dome, would place powerful constraints on their origin and significance. A second major goal is to explore the puzzling absence of the abrupt warming event at 22 ka (seen at Siple Dome) in the nearby Byrd 18O/16O record in the ice (d18Oice), and search for a possible correlative signal in Byrd d15N. A third goal takes advantage of the fact that precise measurements of the oxygen isotopic composition of atmospheric O2 (d18Oatm) are obtained as a byproduct of the d15N measurement. The proposed gas-isotopic measurements will underpin an integrated suite of West Antarctic climate and atmospheric gas records, which will ultimately include the WAIS Divide core. These records will help separate regional from global climate signals, and may place constraints on the cause of abrupt climate change. Education of two graduate students, and training of two staff members in the laboratory, contribute to the nation\u0027s human resource base. Education and outreach will be an important component of the project.", "east": -119.533333, "geometry": "POINT(-119.533333 -80.016667)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Antarctica; Firn Air Isotopes; Not provided; ice cores; Nitrogen Isotopes; LABORATORY; Firn Isotopes; Oxygen Isotopes; Paleoclimate; FIELD SURVEYS; FIELD INVESTIGATION; Siple Dome", "locations": "Antarctica; Siple Dome", "north": -80.016667, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -80.016667, "title": "Nitrogen and oxygen gas isotopes in the Siple Dome and Byrd ice cores", "uid": "p0000450", "west": -119.533333}, {"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; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; WAIS", "people": "Bales, Roger; Frey, Markus; 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; Cryosphere; Geochemistry; Glaciers/Ice Sheet; ITASE; WAIS", "people": "Frey, Markus; McConnell, Joseph; Bales, Roger", "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; USITASE; U.S. ITASE; Ice Core Gas Records; Not provided; Ice Core Data; Polar Firn Air; ice cores; Hydrogen Peroxide; West Antarctic Ice Sheet; Shallow Firn Air; Antarctic Ice Sheet; Snow Chemistry", "locations": "Antarctica; West Antarctica; Antarctic; Antarctic Ice Sheet; West Antarctic Ice Sheet", "north": -76.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Glaciology", "paleo_time": null, "persons": "Bales, Roger; Frey, Markus; McConnell, Joseph", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided", "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": "0453680 Sigman, Daniel", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Robinson et al. 2004 Southern Ocean Diatom-bound Nitrogen and d15N Data", "datasets": [{"dataset_uid": "000119", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Robinson et al. 2004 Southern Ocean Diatom-bound Nitrogen and d15N Data", "url": "https://www.ncdc.noaa.gov/paleo-search/study/8751"}], "date_created": "Wed, 20 May 2009 00:00:00 GMT", "description": "The Southern Ocean may play a central role in causing ice ages and general global climate change. This work will reveal key characteristics of the glacial ocean, and may explain the cause of glacial/interglacial cycles by measuring the abundances of certain isotopes of nitrogen found in fossil diatoms from Antarctic marine sediments. Diatom-bound N is a potentially important recorder of nutrient utilization. The Southern Ocean\u0027s nutrient status, productivity and circulation may be central to setting global atmospheric CO2 contents and other aspects of climate. Previous attempts to make these measurements have yielded ambiguous results. This project includes both technique development and analyses, including measurements on diatoms from both sediment traps and culture experiments. With regard to broader impacts, this grant is focused around the education and academic development of a graduate student, by coupling their research with mentorship of an undergraduate researcher", "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 Earth Sciences", "paleo_time": null, "persons": "Sigman, Daniel", "platforms": "Not provided", "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -90.0, "title": "Application of a New Method for Isotopic Analysis of Diatom Microfossil-bound Nitrogen", "uid": "p0000550", "west": -180.0}, {"awards": "0538630 Severinghaus, Jeffrey", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 01 Apr 2009 00:00:00 GMT", "description": "0538630\u003cbr/\u003eSeveringhaus\u003cbr/\u003eThis award supports a project to produce the first record of Kr/N2 in the paleo-atmosphere as measured in air bubbles trapped in ice cores. These measurements may be indicative of past variations in mean ocean temperature. Knowing the mean ocean temperature in the past will give insight into past variations in deep ocean temperature, which remain poorly understood. Deep ocean temperature variations are important for understanding the mechanisms of climate change. Krypton is highly soluble in water, and its solubility varies with temperature, with higher solubilities at colder water temperatures. A colder ocean during the last glacial period would therefore hold more krypton than today\u0027s ocean. Because the total amount of krypton in the ocean-atmosphere system is constant, the increase in the krypton inventory in the glacial ocean should cause a resultant decrease in the atmospheric inventory of krypton. The primary goal of this work is to develop the use of Kr/N2 as an indicator of paleo-oceanic mean temperature. This will involve improving the analytical technique for the Kr/N2 measurement itself, and measuring the Kr/N2 in air bubbles in ice from the last glacial maximum (LGM) and the late Holocene in the Vostok and GISP2 ice cores. This provides an estimate of LGM mean ocean temperature change, and allows for a comparison between previous estimates of deep ocean temperature during the LGM. The Vostok ice core is ideal for this purpose because of the absence of melt layers, which compromise the krypton and xenon signal. Another goal is to improve precision on the Xe/N2 measurement, which could serve as a second, independent proxy of ocean temperature change. A mean ocean temperature time series during this transition may help to explain these observations. Additionally, the proposed work will measure the Kr/N2 from marine isotope stage (MIS) 3 in the GISP2 ice core. Knowing the past ocean temperature during MIS 3 will help to constrain sea level estimates during this time period. The broader impacts of the proposed work: are that it will provide the first estimate of the extent and timing of mean ocean temperature change in the past. This will help to constrain previously proposed mechanisms of climate change involving large changes in deep ocean temperature. This project will also support the education of a graduate student. The PI gives interviews and talks to the media and public about climate change, and the work will enhance these outreach activities. Finally, the work will occur during the International Polar Year (IPY), and will underscore the unique importance of the polar regions for understanding the global atmosphere and ocean system.", "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": "Severinghaus, Jeffrey P.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Paleoatmospheric Krypton and Xenon Abundances from Trapped Air in Polar Ice as Indicators of Past Mean Ocean Temperature", "uid": "p0000553", "west": null}, {"awards": "0739452 Mukhopadhyay, Sujoy", "bounds_geometry": "POLYGON((161 -76,161.2 -76,161.4 -76,161.6 -76,161.8 -76,162 -76,162.2 -76,162.4 -76,162.6 -76,162.8 -76,163 -76,163 -76.2,163 -76.4,163 -76.6,163 -76.8,163 -77,163 -77.2,163 -77.4,163 -77.6,163 -77.8,163 -78,162.8 -78,162.6 -78,162.4 -78,162.2 -78,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,161 -77.8,161 -77.6,161 -77.4,161 -77.2,161 -77,161 -76.8,161 -76.6,161 -76.4,161 -76.2,161 -76))", "dataset_titles": "Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica", "datasets": [{"dataset_uid": "600074", "doi": "10.15784/600074", "keywords": "Antarctica; Cosmogenic Dating; Cryosphere; Dry Valleys; Glaciers/Ice Sheet; Glaciology; Paleoclimate; Sample/Collection Description; Solid Earth", "people": "Mukhopadhyay, Sujoy", "repository": "USAP-DC", "science_program": null, "title": "Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica", "url": "https://www.usap-dc.org/view/dataset/600074"}], "date_created": "Mon, 30 Mar 2009 00:00:00 GMT", "description": "This project seeks to answer a simple question: how old are potholes and related geomorphic features found in the uplands of the McMurdo Dry Valleys, Antarctica? Some research suggests that they are over ten million years old and date the growth of the East Antarctic Ice Sheet, the world?s largest. However, some evidence suggests that these are young, erosional features that continuing to evolve to this day. This project uses cosmogenic nuclide dating to determine the age of the pothole floors. The results are important for determining the ice sheet?s history and interpreting the O-isotope record from the marine sediment cores, key records of global climate. Broader impacts include K12 outreach and incorporation of outcomes into university courses.", "east": 163.0, "geometry": "POINT(162 -77)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Mukhopadhyay, Sujoy", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica", "uid": "p0000461", "west": 161.0}, {"awards": null, "bounds_geometry": null, "dataset_titles": "Radium and Thorium isotope data summaries from AMLR and NBP cruises to the Antarctic in 2006", "datasets": [{"dataset_uid": "600003", "doi": "", "repository": "USAP-DC", "science_program": null, "title": "Radium and Thorium isotope data summaries from AMLR and NBP cruises to the Antarctic in 2006", "url": "http://www.usap-dc.org/view/dataset/600003"}], "date_created": "Thu, 26 Mar 2009 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": null, "locations": null, "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": null, "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "0440615 Brook, Edward; 0440498 White, James; 0440602 Saltzman, Eric; 0440759 Sowers, Todd; 0440701 Severinghaus, Jeffrey; 0440509 Battle, Mark", "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": "609638", "doi": "10.7265/N56971HF", "keywords": "Antarctica; Cryosphere; 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": "609493", "doi": "10.7265/N5319SV3", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; WAIS divide; WAIS Divide Ice Core", "people": "Taylor, Kendrick C.; McConnell, Joseph; Brook, Edward J.; Mitchell, Logan E; Sowers, Todd A.", "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": "601357", "doi": "10.15784/601357", "keywords": "Antarctica; Atmospheric Gases; Cryosphere; gas measurement; Ice Core; Ice Core Gas Records; Trace Gases", "people": "Aydin, Murat; Saltzman, Eric", "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"}, {"dataset_uid": "609412", "doi": "10.7265/N5251G40", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; 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": "609435", "doi": "10.7265/N5J67DW0", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; 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"}], "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; Firn; LABORATORY; Ice Core; Firn Air Isotope Measurements; Shallow Firn Air; FIELD INVESTIGATION; Ice Core Gas Records; GROUND-BASED OBSERVATIONS; Firn Isotopes; gas data; Polar Firn Air; Not provided; Trapped Gases; West Antarctic Ice Sheet; Ice Sheet; Gas; deep core; Firn Air Isotopes; AGDC-project; WAIS Divide-project; FIELD SURVEYS; bore hole; NSIDC \u003e National Snow and Ice Data Center; Atmospheric Gases; Isotope; trace gas species; Ice Core Data; Surface Temperatures; Firn Air; isotopic; air samples; Atmospheric; cores; NSIDC; AGDC; WAIS divide; 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; Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "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": "0512971 Brook, Edward; 0126057 Brook, Edward", "bounds_geometry": null, "dataset_titles": "Antarctic and Greenland Climate Change Comparison; GISP2 (B and D Core) Methane Concentrations; GISP2 (D Core) Helium Isotopes from Interplanetary Dust; GISP2 (D Core) Methane Concentration Data; Siple Dome Methane Record", "datasets": [{"dataset_uid": "609360", "doi": "", "keywords": "Antarctica; Arctic; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; GISP2; Glaciers/Ice Sheet; Ice Core Records; Methane; Paleoclimate; Taylor Dome", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": null, "title": "GISP2 (D Core) Methane Concentration Data", "url": "https://www.usap-dc.org/view/dataset/609360"}, {"dataset_uid": "609125", "doi": "", "keywords": "Arctic; Chemistry:Fluid; Chemistry:Ice; Cryosphere; Geochemistry; GISP2; Glaciers/Ice Sheet; Glaciology; Greenland; Ice Core Records; Methane; Paleoclimate", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": null, "title": "GISP2 (B and D Core) Methane Concentrations", "url": "https://www.usap-dc.org/view/dataset/609125"}, {"dataset_uid": "609253", "doi": "", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Vostok Ice Core", "people": "Chappellaz, Jerome; Brook, Edward J.; Blunier, Thomas; Stauffer, Bernhard", "repository": "USAP-DC", "science_program": null, "title": "Antarctic and Greenland Climate Change Comparison", "url": "https://www.usap-dc.org/view/dataset/609253"}, {"dataset_uid": "609361", "doi": "", "keywords": "Antarctica; Arctic; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; GISP2; Glaciers/Ice Sheet; Ice Core Records; Isotope; Lake Vostok; Paleoclimate; Vostok Ice Core", "people": "Brook, Edward J.; Kurz, Mark D.", "repository": "USAP-DC", "science_program": null, "title": "GISP2 (D Core) Helium Isotopes from Interplanetary Dust", "url": "https://www.usap-dc.org/view/dataset/609361"}, {"dataset_uid": "609124", "doi": "10.7265/N5KH0K8R", "keywords": "Antarctica; Chemistry:Fluid; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; Paleoclimate; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Methane Record", "url": "https://www.usap-dc.org/view/dataset/609124"}], "date_created": "Tue, 16 Dec 2008 00:00:00 GMT", "description": "This award supports work on trapped gases in Antarctic and other ice cores for paleoenvironmental and chronological purposes. The project will complete a ~ 100,000 year, high-resolution record of atmospheric methane from the Siple Dome ice core and use these data to construct a precise chronology for climate events recorded by the Siple Dome record. In addition, the resolution of the GISP2 (Greenland) ice core record will be increased in some critical intervals to help with the Siple Dome chronology and that of future ice cores. Finally, an upgrade to the analytical capabilities of the laboratory, including increasing precision and throughput and decreasing sample size needed for ice core methane measurements will be an important goal of this work. The proposed work will contribute to the understanding of the timing of rapid climate change in the Northern and Southern hemispheres during the last glacial period, the evolution of the global methane budget in the late Quaternary, and the late Quaternary climate history of Antarctica. It will also improve our ability to generate methane records for future ice coring projects, and inform and enrich the educational and outreach activities of our laboratory.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Siple Coast; WAISCORES; GROUND-BASED OBSERVATIONS; Interplanetary Dust; FIELD SURVEYS; Not provided; NSIDC; Ice Sheet; Snow; isotopes; GROUND STATIONS; Ice Core; Siple; Antarctica; Methane; Glaciology; Stratigraphy; Siple Dome; gas measurement", "locations": "Antarctica; Siple Coast; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Glaciology; Antarctic Organisms and Ecosystems; Antarctic Glaciology", "paleo_time": null, "persons": "Blunier, Thomas; Chappellaz, Jerome; Stauffer, Bernhard; Kurz, Mark D.; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "High Resolution Records of Atmospheric Methane in Ice Cores and Implications for Late Quaternary Climate Change", "uid": "p0000034", "west": null}, {"awards": "0636953 Saltzman, Eric", "bounds_geometry": "POINT(-148.82 -81.66)", "dataset_titles": "Carbonyl Sulfide Measurements in the Taylor Dome M3C1 Ice Core; Ice Core Air Carbonyl Sulfide Measurements - Taylor Dome M3C1 Ice Core; Methyl Bromide Measurements in the Taylor Dome M3C1 Ice Core; Methyl Chloride Measurements from the Siple Dome A Deep Core, Antarctica; Methyl Chloride Measurements in the Taylor Dome M3C1 Ice Core", "datasets": [{"dataset_uid": "601361", "doi": "10.15784/601361", "keywords": "Antarctica; Carbonyl Sulfide; Cryosphere; Trace Gases", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": null, "title": "Ice Core Air Carbonyl Sulfide Measurements - Taylor Dome M3C1 Ice Core", "url": "https://www.usap-dc.org/view/dataset/601361"}, {"dataset_uid": "609356", "doi": "10.7265/N56W9807", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Williams, Margaret; Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Methyl Chloride Measurements from the Siple Dome A Deep Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609356"}, {"dataset_uid": "609600", "doi": "10.7265/N5PG1PPB", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Methyl Chloride Measurements in the Taylor Dome M3C1 Ice Core", "url": "https://www.usap-dc.org/view/dataset/609600"}, {"dataset_uid": "609599", "doi": "10.7265/N5S75D8P", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Carbonyl Sulfide Measurements in the Taylor Dome M3C1 Ice Core", "url": "https://www.usap-dc.org/view/dataset/609599"}, {"dataset_uid": "609598", "doi": "10.7265/N5X0650D", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "people": "Saltzman, Eric; Aydin, Murat", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Methyl Bromide Measurements in the Taylor Dome M3C1 Ice Core", "url": "https://www.usap-dc.org/view/dataset/609598"}], "date_created": "Wed, 22 Oct 2008 00:00:00 GMT", "description": "Saltzman/0636953\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to measure methyl chloride, methyl bromide, and carbonyl sulfide in air extracted from Antarctic ice cores. Previous measurements in firn air and shallow ice cores suggest that the ice archive contains paleo-atmospheric signals for these gases. The goal of this study is to extend these records throughout the Holocene and into the last Glacial period to examine the behavior of these trace gases over longer time scales and a wider range of climatic conditions. These studies are exploratory, and both the stability of these trace gases and the extent to which they may be impacted by in situ processes will be assessed. This project will involve sampling and analyzing archived ice core samples from the Siple Dome, Taylor Dome, Byrd, and Vostok ice cores. The ice core samples will be analyzed by dry extraction, with gas chromatography/mass spectrometry with isotope dilution. The ice core measurements will generate new information about the range of natural variability of these trace gases in the atmosphere. The intellectual merit of this project is that this work will provide an improved basis for assessing the impact of anthropogenic activities on biogeochemical cycles, and new insight into the climatic sensitivity of the biogeochemical processes controlling atmospheric composition. The broader impact of this project is that there is a strong societal interest in understanding how man\u0027s activities impact the atmosphere, and how atmospheric chemistry may be altered by future climate change. The results of this study will contribute to the development of scenarios used for future projections of stratospheric ozone and climate change. In terms of human development, this project will support the doctoral dissertation of a graduate student in Earth System Science, and undergraduate research on polar ice core chemistry. This project will also contribute to the development of an Earth Sciences teacher training curriculum for high school teachers in the Orange County school system in collaboration with an established, NSF-sponsored Math and Science Partnership program (FOCUS).", "east": -148.82, "geometry": "POINT(-148.82 -81.66)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Antarctica; Methyl Bromide; Antarctic; Ice Core Gas Records; Ice Core Data; Carbonyl Sulfide; AGDC-project; Methyl Chloride; Antarctic Ice Sheet; Siple Dome; Trace Gases; Ice Core Chemistry; Atmospheric Chemistry; biogeochemical; West Antarctic Ice Sheet; LABORATORY; ice cores; Ice Core; West Antarctica", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet; Siple Dome; West Antarctica; West Antarctic Ice Sheet", "north": -81.66, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Saltzman, Eric; Aydin, Murat; Williams, Margaret", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core; Siple Dome Ice Core", "south": -81.66, "title": "Methyl Chloride, Methyl Bromide, and Carbonyl Sulfide in Deep Antarctic Ice Cores", "uid": "p0000042", "west": -148.82}, {"awards": "0228052 Kreutz, Karl", "bounds_geometry": "POLYGON((161.0434 -77.3002,161.241645 -77.3002,161.43989 -77.3002,161.638135 -77.3002,161.83638 -77.3002,162.034625 -77.3002,162.23287 -77.3002,162.431115 -77.3002,162.62936 -77.3002,162.827605 -77.3002,163.02585 -77.3002,163.02585 -77.3784846,163.02585 -77.4567692,163.02585 -77.5350538,163.02585 -77.6133384,163.02585 -77.691623,163.02585 -77.7699076,163.02585 -77.8481922,163.02585 -77.9264768,163.02585 -78.0047614,163.02585 -78.083046,162.827605 -78.083046,162.62936 -78.083046,162.431115 -78.083046,162.23287 -78.083046,162.034625 -78.083046,161.83638 -78.083046,161.638135 -78.083046,161.43989 -78.083046,161.241645 -78.083046,161.0434 -78.083046,161.0434 -78.0047614,161.0434 -77.9264768,161.0434 -77.8481922,161.0434 -77.7699076,161.0434 -77.691623,161.0434 -77.6133384,161.0434 -77.5350538,161.0434 -77.4567692,161.0434 -77.3784846,161.0434 -77.3002))", "dataset_titles": "Late Holocene Climate Variability, Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "609399", "doi": "10.7265/N5FF3Q92", "keywords": "Antarctica; Borehole Temperature; Chemistry:Ice; Cryosphere; Dry Valleys; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Mass Balance; Paleoclimate; Physical Properties", "people": "Kreutz, Karl; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": null, "title": "Late Holocene Climate Variability, Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609399"}], "date_created": "Tue, 21 Oct 2008 00:00:00 GMT", "description": "This award supports a project to collect and develop high-resolution ice core records from the Dry Valleys region of Antarctica, and provide interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). The project will test hypotheses related to ocean/atmosphere teleconnections (e.g., El Nino Southern Oscillation, Antarctic Oscillation) that may be responsible for major late Holocene climate events such as the Little Ice Age in the Southern Hemisphere. Conceptual and quantitative models of these processes in the Dry Valleys during the late Holocene are critical for understanding recent climate changes, and represent the main scientific merit of the project. We plan to collect intermediate-length ice cores (100-200m) at four sites along transects in Taylor Valley and Wright Valley, and analyze each core at high resolution for stable isotopes (d18O, dD), major ions (Na+, Mg2+, Ca2+, K+, NH4+, Cl-, NO3-, SO42-, MSA), and trace elements (Al, Fe, S, Sr, B). A suite of statistical techniques will be applied to the multivariate glaciochemical dataset to identify chemical associations and to calibrate the time-series records with available instrumental data. Broader impacts of the project include: 1) contributions to several ongoing interdisciplinary Antarctic research programs; 2) graduate and undergraduate student involvement in field, laboratory, and data interpretation activities; 3) use of project data and ideas in several UMaine courses and outreach activities; and 4) data dissemination through peer-reviewed publications, UMaine and other paleoclimate data archive websites, and presentations at national and international meetings.", "east": 163.02585, "geometry": "POINT(162.034625 -77.691623)", "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 SPECTROMETERS/RADIOMETERS \u003e MC-ICP-MS; 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 TEMPERATURE/HUMIDITY SENSORS \u003e HUMIDITY SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS", "is_usap_dc": true, "keywords": "Holocene; Climate Research; AWS Climate Data; Paleoclimate; Climate Variation; Dry Valleys; Wright Valley; ice cores; Little Ice Age; variability; Stable Isotopes; FIELD INVESTIGATION; Antarctic Oscillation; glaciochemical; Climate; GPS; LABORATORY; Not provided; Climate Change; Ice Core Records; ENSO; Antarctica; El Nino Southern Oscillation; Taylor Valley; FIELD SURVEYS", "locations": "Antarctica; Dry Valleys; Taylor Valley", "north": -77.3002, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kreutz, Karl; Arcone, Steven; Mayewski, Paul A.", "platforms": "SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.083046, "title": "Dry Valleys Late Holocene Climate Variability", "uid": "p0000155", "west": 161.0434}, {"awards": "0124049 Berger, Glenn", "bounds_geometry": "POLYGON((161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.20000000000002 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163.20000000000002 -77.5,163.4 -77.5,163.4 -77.52,163.4 -77.54,163.4 -77.56,163.4 -77.58,163.4 -77.6,163.4 -77.62,163.4 -77.64,163.4 -77.66,163.4 -77.68,163.4 -77.7,163.20000000000002 -77.7,163 -77.7,162.8 -77.7,162.6 -77.7,162.4 -77.7,162.20000000000002 -77.7,162 -77.7,161.8 -77.7,161.6 -77.7,161.4 -77.7,161.4 -77.68,161.4 -77.66,161.4 -77.64,161.4 -77.62,161.4 -77.6,161.4 -77.58,161.4 -77.56,161.4 -77.54,161.4 -77.52,161.4 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 25 Aug 2008 00:00:00 GMT", "description": "0124049\u003cbr/\u003eBerger\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the Dry Valleys of the McMurdo Sound region of Antarctica. Using a modified Livingstone corer, transects of long cores will be obtained from Lakes Fryxell, Bonney, Joyce, and Vanda. A multiparameter approach will be employed which is designed to extract the greatest possible amount of former water-level, glaciological, and paleoenvironmental data from Dry Valleys lakes. Estimates of hydrologic changes will come from different proxies, including grain size, stratigraphy, evaporite mineralogy, stable isotope and trace element chemistry, and diatom assemblage analysis. The chronology, necessary to integrate the cores with the geomorphological record, as well as for comparisons with Antarctic ice-core and glacial records, will come from Uranium-Thorium, Uranium-Helium, and Carbon-14 dating of carbonates, as well as luminescence sediment dating. Evaluation of the link between lake-level and climate will come from hydrological and energy-balance modelling. Combination of the more continuous lake-core sequences with the spatially extensive geomorphological record will result in an integrated Antarctic lake-level and paleoclimate dataset that extends back at least 30,000 years. This record will be compared to Dry Valleys glacier records and to the Antarctic ice cores to address questions of regional climate variability, and then to other Southern Hemisphere and Northern Hemisphere records to assess interhemispheric synchrony or asynchrony of climate change.", "east": 163.4, "geometry": "POINT(162.4 -77.6)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LASERS", "is_usap_dc": false, "keywords": "lake cores; luminescence geochronology; Stratigraphy; Climate Variability; Dry Valleys; Antarctic lake-level; shoreline deposits; Grain Size; Paleoclimate; Antarctica; LABORATORY", "locations": "Dry Valleys; Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Berger, Glenn; Hall, Brenda; Doran, Peter", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -77.7, "title": "Collaborative Research: Millennial Scale Fluctuations of Dry Valleys Lakes: Implications for Regional Climate Variability and the Interhemispheric (a)Synchrony of Climate Change", "uid": "p0000219", "west": 161.4}, {"awards": "0648509 Sletten, Ronald", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 15 Aug 2008 00:00:00 GMT", "description": "This Small Grant for Exploratory Research explores the use of magnesium isotopes in understanding the preservation of ice in soils from the Dry Valleys of Antarctica. With such little precipitation in the region, this ice should have completely sublimed away, nonetheless there is geologic evidence of ten-million-year-old ice in some areas. Its ubiquitous presence in Dry Valley\u0027s soils implies some form of recharge, seemingly incompatible with the low precipitation rates. This project studies the Mg-isotopes found in soluble salts and, by association, water transport. Magnesium isotopes undergo mass dependent fractionation during the volatilization and condensation, and thus offer the possibility to constrain both the water source and other processes by which ice is mobilized. The measurements require the high precision made possible only recently by development of the MC-ICPMS. The method will be applied to Mg-salts extracted from archived Antarctic soils, as well as cores recovered by the 1970s Dry Valley Drilling Project. \u003cbr/\u003e\u003cbr/\u003eIn terms of broader impacts, this project would support a graduate student, who would learn cutting edge geochemical techniques while applying them to an exciting earth science question. This work is critical to understanding the environmental record offered by the Dry Valleys, including the deep ice records that may give seven-million year old samples of the earth\u0027s atmosphere. The work also has applications to understanding permafrost on Mars and interpreting recent rover observations.", "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": "Sletten, Ronald S.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Small Grant Exploratory Research: The Application of Mg Isotopes as an Indictor for Water and Brine Migration into Dry Valley Permafrost", "uid": "p0000089", "west": null}, {"awards": "0338224 Putkonen, Jaakko", "bounds_geometry": "POLYGON((161 -77,161.3 -77,161.6 -77,161.9 -77,162.2 -77,162.5 -77,162.8 -77,163.1 -77,163.4 -77,163.7 -77,164 -77,164 -77.1,164 -77.2,164 -77.3,164 -77.4,164 -77.5,164 -77.6,164 -77.7,164 -77.8,164 -77.9,164 -78,163.7 -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 -77.9,161 -77.8,161 -77.7,161 -77.6,161 -77.5,161 -77.4,161 -77.3,161 -77.2,161 -77.1,161 -77))", "dataset_titles": "Cosmogenic nucilde data at ICE-D", "datasets": [{"dataset_uid": "200298", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nucilde data at ICE-D", "url": "https://version2.ice-d.org/antarctica/nsf/"}], "date_created": "Tue, 20 Nov 2007 00:00:00 GMT", "description": "This work will study cosmogenic isotope profiles of rock and sediment in the Dry Valleys of Antarctica to understand their origin. The results will provide important constraints on the history of the East Antarctic Ice Sheet. The near-perfect preservation of volcanic ash and overlying sediments suggests that hyperarid cold conditions have prevailed in the Dry Valleys for over 10 Myr. The survival of these sediments also suggests that warm-based ice has not entered the valley system and ice sheet expansion has been minimal. Other evidence, however, suggests that the Dry Valleys have experienced considerably more sediment erosion than generally believed: 1) the cosmogenic exposure ages of boulders and bedrock in the Valleys all show generally younger ages than volcanic ash deposits used to determine minimum ages of moraines and drifts, 2) there appears to be a discrepancy between the suggested extreme preservation of unconsolidated slope deposits (\u003e10 Myr) and adjacent bedrock that has eroded 2.6-6 m during the same time interval. The fact that the till and moraine exposure ages generally post date the overlying volcanic ash deposits could reflect expansion of continental ice sheet into the Dry Valleys with cold-based ice, thus both preserving the landscape and shielding the surfaces from cosmic radiation. Another plausible explanation of the young cosmogenic exposure ages is erosion of the sediments and gradual exhumation of formerly buried boulders to the surface. Cosmogenic isotope systematics are especially well suited to address these questions. We will measure multiple cosmogenic isotopes in profiles of rock and sediment to determine the minimum exposure ages, the degree of soil stability or mixing, and the shielding history of surfaces by cold based ice. We expect to obtain unambiguous minimum ages for deposits. In addition, we should be able to identify areas disturbed by periglacial activity, constrain the timing of such activity, and account for the patchy preservation of important stratigraphic markers such as volcanic ash. The broader impacts of this project include graduate and undergraduate education, and improving our understanding of the dynamics of Southern Hemisphere climate on timescales of millions of years, which has major implications for understanding the controls and impacts of global climate change.", "east": 164.0, "geometry": "POINT(162.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "ICE SHEETS; Dry Valleys; Not provided", "locations": "Dry Valleys", "north": -77.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Putkonen, Jaakko", "platforms": "Not provided", "repo": "ICE-D", "repositories": "ICE-D", "science_programs": null, "south": -78.0, "title": "Stability of Landscapes and Ice Sheets in Dry Valleys, Antarctica: A Systematic Study of Exposure Ages of Soils and Surface Deposits", "uid": "p0000575", "west": 161.0}, {"awards": "0337891 Brook, Edward", "bounds_geometry": "POINT(158 -77.666667)", "dataset_titles": "Atmospheric CO2 and Climate: Byrd Ice Core, Antarctica; Atmospheric CO2 and Climate: Taylor Dome Ice Core, Antarctica", "datasets": [{"dataset_uid": "609315", "doi": "10.7265/N5542KJK", "keywords": "Antarctica; Atmosphere; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "people": "Ahn, Jinho; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Atmospheric CO2 and Climate: Taylor Dome Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609315"}, {"dataset_uid": "609314", "doi": "10.7265/N58W3B80", "keywords": "Antarctica; Atmosphere; Byrd Glacier; Byrd Ice Core; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate", "people": "Brook, Edward J.; Ahn, Jinho", "repository": "USAP-DC", "science_program": "Byrd Ice Core", "title": "Atmospheric CO2 and Climate: Byrd Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609314"}], "date_created": "Mon, 05 Nov 2007 00:00:00 GMT", "description": "This award supports the development of a new laboratory capability in the U.S. to measure CO2 in ice cores and investigate millennial-scale changes in CO2 during the last glacial period using samples from the Byrd and Siple Dome ice cores. Both cores have precise relative chronologies based on correlation of methane and the isotopic composition of atmospheric oxygen with counterpart records from Greenland ice cores. The proposed work will therefore allow comparison of the timing of CO2 change, Antarctic temperature change, and Greenland temperature change on common time scales. Such comparisons are vital for evaluating models that explain changes in atmospheric CO2. The techniques being developed will also be available for future projects, specifically the proposed Inland WAIS ice core, for which a highly detailed CO2 record is a major objective, and studies greenhouse and other atmospheric gases and their isotopic composition for which dry extraction is necessary (stable isotopes in CO2, for example). There are many broad impacts of the proposed work. Ice core greenhouse gas records are central contributions of paleoclimatology to research and policy-making concerning global change. The proposed work will enhance those contributions by improving our understanding of the natural cycling of the most important greenhouse gas. It will contribute to the training of a postdoctoral researcher, who will be an integral part of an established research group and benefit from the diverse paleoclimate and geochemistry community at OSU. The PI teaches major and non-major undergraduate and graduate courses on climate and global change. The proposed work will enrich those courses and the courses will provide an opportunity for the postdoctoral researcher to participate in teaching by giving guest lectures. The PI also participates in a summer climate workshop for high school teachers at Washington State University and the proposed work will enrich that contribution. The extraction device that is built and the expertise gained in using it will be resources for the ice core community and available for future projects. Data will be made available through established national data center and the equipment designs will also be made available to other researchers.", "east": 158.0, "geometry": "POINT(158 -77.666667)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Ice Core; Climate Change; CO2; ice cores; Atmospheric Chemistry; Atmospheric CO2; LABORATORY; Not provided; Ice Core Data; Climate; Ice Core Chemistry; Atmospheric Gases; Ice Core Gas Records; GROUND STATIONS; Climate Research", "locations": null, "north": -77.666667, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Ahn, Jinho; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": -77.666667, "title": "Developing Dry Extraction of Ice Core Gases and Application to Millennial-Scale Variability in Atmospheric CO2", "uid": "p0000268", "west": 158.0}, {"awards": "0233303 Jacobs, Stanley", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 09 Jul 2007 00:00:00 GMT", "description": "Major portions of the Antarctic Ice Sheet float in the surrounding ocean, at the physical and intellectual boundaries of oceanography and glaciology. These ice shelves lose mass continuously by melting into the sea, and periodically by the calving of icebergs. Those losses are compensated by the outflow of grounded ice, and by surface accumulation and basal freezing. Ice shelf sources and sinks vary on several time scales, but their wastage terms are not yet well known. Reports of substantial ice shelf retreat, regional ocean freshening and increased ice velocity and thinning are of particular concern at a time of warming ocean temperatures in waters that have access to deep glacier grounding lines.\u003cbr/\u003eThis award supports a study of the attrition of Antarctic ice shelves, using recent ocean geochemical measurements and drawing on numerical modeling and remote sensing resources. In cooperation with associates at Columbia University and the British Antarctic Survey, measurements of chlorofluorocarbon, helium, neon and oxygen isotopes will be used to infer basal melting beneath the Ross Ice Shelf, and a combination of oceanographic and altimeter data will be used to investigate the mass balance of George VI Ice Shelf. Ocean and remote sensing observations will also be used to help refine numerical models of ice cavity circulations. The objectives are to reduce uncertainties between different estimates of basal melting and freezing, evaluate regional variability, and provide an update of an earlier assessment of circumpolar net melting.\u003cbr/\u003eA better knowledge of ice shelf attrition is essential to an improved understanding of ice shelf response to climate change. Large ice shelf calving events can alter the ocean circulation and sea ice formation, and can lead to logistics problems such as those recently experienced in the Ross Sea. Broader impacts include the role of ice shelf meltwater in freshening and stabilizing the upper ocean, and in the formation of Antarctic Bottom Water, which can be traced far into the North Atlantic. To the extent that ice shelf attrition influences the flow of grounded ice, this work also has implications for ice sheet stability and sea level rise.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Basal freezing; basal melting; Ice Sheet; ice sheet stability; Not provided; Oceanography; Ice Velocity; Glaciology; Sea Level Rise; outflow; mass; Ross Ice Sheet; Ice shelf meltwater; George VI Ice Shelf; numerical modeling; ice cavity circulations", "locations": "Ross Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Jacobs, Stanley", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Melting and Calving of Antarctic Ice Shelves", "uid": "p0000730", "west": null}, {"awards": "9526556 Sowers, Todd", "bounds_geometry": "POINT(-148.3023 -81.403)", "dataset_titles": "Carbon-13 Isotopic Composition of Atmospheric Methane in Firn Air, South Pole and Siple Dome, Antarctica", "datasets": [{"dataset_uid": "609310", "doi": "10.7265/N5ST7MR2", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; Siple Dome; Snow/Ice; South Pole", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Carbon-13 Isotopic Composition of Atmospheric Methane in Firn Air, South Pole and Siple Dome, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609310"}], "date_created": "Mon, 09 Jul 2007 00:00:00 GMT", "description": "This award is for support for a program to reconstruct records of the isotopic composition of paleoatmospheric methane and nitrous oxide covering the last 200,000 years. High resolution measurements of the carbon-13 isotopic composition of methane from shallow ice cores will help to determine the relative contributions of biogenic (wetlands, rice fields and ruminants) and abiogenic (biomass burning and natural gas) methane emissions which have caused the concentrations of this gas to increase at an exponential rate during the anthropogenic period. Isotopic data on methane and nitrous oxide over glacial/interglacial timescales will help determine the underlying cause of the large concentration variations that are known to occur. This project will make use of a new generation mass spectrometer which is capable of generating precise isotopic information on nanomolar quantities of methane and nitrous oxide, which means that samples can be 1000 times smaller than those needed for a standard isotope ratio instrument. The primary objective of the work is to further our understanding of the biogeochemical cycles of these two greenhouse gases throughout the anthropogenic period as well as over glacial interglacial timescales.", "east": -148.3023, "geometry": "POINT(-148.3023 -81.403)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Ice Core; Firn Air Isotope Measurements; Ice Core Chemistry; Firn Isotopes; Stable Isotopes; Methane; Carbon; Paleoclimate; LABORATORY; AGDC; Siple Dome; Antarctica; Ice Core Data; Firn Air Isotopes; Antarctic Ice Sheet", "locations": "Antarctica; Antarctic Ice Sheet; Siple Dome", "north": -81.403, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Sowers, Todd A.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.403, "title": "Constructing Paleoatmospheric Records of the Isotopic Composition of Methane and Nitrous Oxide", "uid": "p0000611", "west": -148.3023}, {"awards": "0548918 van de Flierdt, Christina-Maria", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 07 Jun 2007 00:00:00 GMT", "description": "This Small Grant for Exploratory Research supports development of a geochemical technique to time the onset of glacial erosion from Antarctica\u0027s continental ice sheets. The technique pairs neodymium (Nd) and hafnium (Hf) isotope proxies from the authigenic (seawater-derived) ferromanganese phase precipitated in marine sediments. This technique promises to be a sensitive indicator of glacial erosion. Non-radiogenic Hf is contained in the mineral zircon, which can only be released by the abrasive grinding that accompanies glacial erosion. Previous attempts to develop this technique encountered difficulty due to the minute amounts of Hf involved and the difficulty in its extraction. The PIs have developed a new chemical protocol that should allow them to selectively extract authigenic Hf from bulk sediments. If successful, studies of the Eocene-Oligocene boundary from two drill cores the Weddell Sea and Kerguelen Plateau will be carried out. This boundary is considered the initiation point for formation of Antarctica\u0027s current ice sheets. If successful, this method will benefit scientists with interests as diverse as continental weathering, ocean circulation, Cenozoic paleoceanography and paleoclimate, and Antarctic geology. \u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this work are development of a new analytical technique that may improve society\u0027s understanding of the potential for global climate change from the perspective of the deep time record.", "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": "Van De Flierdt, Christina-Maria", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "SGER: Development of the Paired Authigenic Neodymium-Hafnium Isotope Weathering Tracer From Marine Sediments in the Circum Antarctic Realm", "uid": "p0000130", "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; scans", "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": "0229573 Mayewski, Paul", "bounds_geometry": null, "dataset_titles": "Antarctic Mean Annual Temperature Map", "datasets": [{"dataset_uid": "609318", "doi": "10.7265/N51C1TTV", "keywords": "Antarctica; Cryosphere; 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; 10 m temperature; Antarctic; East Antarctic Plateau; FIELD SURVEYS; Antarctica; Not provided", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet; West Antarctica; West Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Dixon, Daniel A.", "platforms": "Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "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": "0126202 Blankenship, Donald; 0125579 Cuffey, Kurt", "bounds_geometry": "POLYGON((160 -77.6,160.25 -77.6,160.5 -77.6,160.75 -77.6,161 -77.6,161.25 -77.6,161.5 -77.6,161.75 -77.6,162 -77.6,162.25 -77.6,162.5 -77.6,162.5 -77.63,162.5 -77.66,162.5 -77.69,162.5 -77.72,162.5 -77.75,162.5 -77.78,162.5 -77.81,162.5 -77.84,162.5 -77.87,162.5 -77.9,162.25 -77.9,162 -77.9,161.75 -77.9,161.5 -77.9,161.25 -77.9,161 -77.9,160.75 -77.9,160.5 -77.9,160.25 -77.9,160 -77.9,160 -77.87,160 -77.84,160 -77.81,160 -77.78,160 -77.75,160 -77.72,160 -77.69,160 -77.66,160 -77.63,160 -77.6))", "dataset_titles": "Ablation Rates of Taylor Glacier, Antarctica; Stable Isotopes of Ice on the Surface of Taylor Glacier, Antarctica; Surface Velocities of Taylor Glacier, Antarctica", "datasets": [{"dataset_uid": "609326", "doi": "10.7265/N5N29TW8", "keywords": "Ablation Poles; Ablation Rates; Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Taylor Glacier", "people": "Kavanaugh, Jeffrey; Cuffey, Kurt M.; Bliss, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Ablation Rates of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609326"}, {"dataset_uid": "609323", "doi": "10.7265/N5WM1BBZ", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Isotope; Taylor Glacier", "people": "Bliss, Andrew; Cuffey, Kurt M.; Kavanaugh, Jeffrey; Aciego, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Stable Isotopes of Ice on the Surface of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609323"}, {"dataset_uid": "609324", "doi": "10.7265/N5RV0KM7", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Velocity; Taylor Glacier", "people": "Aciego, Sarah; Cuffey, Kurt M.; Bliss, Andrew; Kavanaugh, Jeffrey", "repository": "USAP-DC", "science_program": null, "title": "Surface Velocities of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609324"}], "date_created": "Tue, 13 Feb 2007 00:00:00 GMT", "description": "This award supports a project to significantly improve our understanding of how Taylor Glacier flows and responds to climate changes. Taylor Glacier drains the Taylor Dome region of the East Antarctic Ice Sheet and terminates in Taylor Valley, one of the Dry Valleys of Victoria Land. It provides a crucial and unique link between two intensively studied Antarctic environments: the Taylor Dome, from which a 130 kyr ice core paleoclimate record has recently been extracted, and the Dry Valleys, a pivotal Long-Term Ecological Research (LTER) site and a focus of research on geomorphology and glacial geology. The proposed work will thus make an important contribution to ongoing efforts to exploit the Taylor Dome - Dry Valleys system to build a uniquely comprehensive view of regional long-term environmental changes. The proposed work has two complementary components: field research and numerical modelling. Two field seasons will be used to measure velocity, surface strain rate, mass balance, ice thickness, glacier bed reflectance, and subglacial topography, along a nearly complete longitudinal transect of the Taylor Glacier, and along select cross-valley transects. This information will be used to constrain numerical models of ice and heat flow for the Taylor Dome - Taylor Glacier system. These calibrated models will be used to analyze the time-dependent response of the Taylor Glacier to climate changes. The synthesis of results will be aimed to improve understanding of the glacial geomorphology of Taylor Valley, and to illuminate impacts on the Taylor Valley lakes ecosystem. The project will have a major role in furthering the careers of a doctoral-level graduate student and a post-doctoral researcher.", "east": 162.5, "geometry": "POINT(161.25 -77.75)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Oxygen Isotopes; Glacier; Glacier Surface; Glacier Surface Ablation; Ice Velocity; Velocity Measurements; Taylor Glacier; Isotope; GPS; Ice Sheet Elevation; Not provided; FIELD INVESTIGATION; Ice Surface Elevation; Ablation; Elevation; Deuterium; GROUND-BASED OBSERVATIONS; Glacier Surface Ablation Rate; Surface Elevation", "locations": "Taylor Glacier", "north": -77.6, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Bliss, Andrew; Kavanaugh, Jeffrey; Aciego, Sarah; Cuffey, Kurt M.; Morse, David L.; Blankenship, Donald D.", "platforms": "Not provided; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.9, "title": "Collaborative Research: Dynamics and Climatic Response of the Taylor Glacier System", "uid": "p0000084", "west": 160.0}, {"awards": "0126270 Doran, Peter", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 05 Feb 2007 00:00:00 GMT", "description": "Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Doran, Peter", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Paleoclimate Inferred from Lake Sediment Cores in Taylor Valley, Antarctica", "uid": "p0000092", "west": null}, {"awards": "9526566 Bindschadler, Robert", "bounds_geometry": null, "dataset_titles": "Decadal-Length Composite West Antarctic Air Temperature Records", "datasets": [{"dataset_uid": "609097", "doi": "10.7265/N55D8PS0", "keywords": "Antarctica; Atmosphere; Automated Weather Station (AWS); Cryosphere; Meteorology; Temperature; West Antarctica", "people": "Shuman, Christopher A.; Stearns, Charles R.", "repository": "USAP-DC", "science_program": null, "title": "Decadal-Length Composite West Antarctic Air Temperature Records", "url": "https://www.usap-dc.org/view/dataset/609097"}], "date_created": "Tue, 28 Nov 2006 00:00:00 GMT", "description": "This award is for support for a research program involving the use of passive microwave data to validate key paleoclimate indicators used in glaciologic research. The specific contributions of this research are: 1) to define the timing and spatial extent of hoar complexes, which may serve as visible, annual stratigraphic markers in ice cores, through a combination of satellite passive microwave data and field observations; and 2) to monitor temperature trends at the site with calibrated passive microwave brightness temperatures and to correlate these trends to proxy temperatures provided by oxygen and hydrogen stable isotope ratio profiles from snow pits and/or ice cores. The work will take place at Siple Dome, Antarctica as part of the field activities associated with the ice core drilling program there.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e SMMR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e SSM/I", "is_usap_dc": true, "keywords": "West Antarctica; Surface Temperatures; Passive Microwave Brightness Temperatures; Special Sensor Microwave/Imager; Scanning Multichannel Microwave Radiometer; Inland; SSM/I; SSMR; AWS Byrd Station; Automated Weather Stations; NIMBUS-7; Interior; Emissivity Modeling; Tbs; Antarctica; Near-surface Air Temperatures; West Antarctic Ice Sheet; Not provided; DMSP; AWS Siple; NSIDC; AWS Lynn; AWS Lettau; AWS", "locations": "Antarctica; West Antarctica; West Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bindschadler, Robert; Shuman, Christopher A.; Stearns, Charles R.", "platforms": "SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e NIMBUS \u003e NIMBUS-7; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e DEFENSE METEOROLOGICAL SATELLITE PROGRAM (DMSP) \u003e DMSP; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Passive Microwave Remote Sensing for Paleoclimate Indicators at Siple Dome, Antarctica", "uid": "p0000191", "west": null}, {"awards": "0230452 Severinghaus, Jeffrey", "bounds_geometry": "POINT(124.5 -80.78)", "dataset_titles": "Antarctic megadunes", "datasets": [{"dataset_uid": "000191", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "Antarctic megadunes", "url": "http://nsidc.org/antarctica/megadunes/"}], "date_created": "Wed, 27 Sep 2006 00:00:00 GMT", "description": "This award supports a study of the chemical composition of air in the snow layer (firn) in a region of \"megadunes\" near Vostok station, Antarctica. It will test the hypothesis that a deep \"convective zone\" of vigorous wind-driven mixing can prevent gas fractionation in the upper one-third of the polar firn layer. In the megadunes, ultralow snow accumulation rates lead to structural changes (large grains, pipes, and cracks) that make the permeability of firn to air movement orders of magnitude higher than normal. The unknown thickness of the convective zone has hampered the interpretation of ice core 15N/14N and 40Ar/36Ar ratios as indicators of past firn thickness, which is a key constraint on the climatically important variables of temperature, accumulation rate, and gas age-ice age difference. Studying this \"extreme end-member\" example will better define the role of the convective zone in gas reconstructions. This study will pump air from a profile of ~20 depths in the firn, to definitively test for the presence of a convective zone based on the fit of observed 15 N/14N and 40Ar/36Ar to a molecular- and eddy-diffusion model. Permeability measurements on the core and 2-D air flow modeling (in collaboration with M. Albert) will permit a more physically realistic interpretation of the isotope data and will relate mixing vigor to air velocities. A new proxy indicator of convective zone thickness will be tested on firn and ice core bubble air, based on the principle that isotopes of slow-diffusing heavy noble gases (Kr, Xe) should be more affected by convection than isotopes of fast-diffusing N2 . These tools will be applied to a test of the hypothesis that the megadunes and a deep convective zone existed at the Vostok site during glacial periods, which would explain the anomalously low 15N/14N and 40Ar/36Ar in the Vostok ice core glacial periods. The broader impacts of this work include 1) clarification of phase relationships of greenhouse gases and temperature in ice core records, with implications for understanding of past and future climates, 2) education of one graduate student, and 3) building of collaborative relationships with five investigators.", "east": 124.5, "geometry": "POINT(124.5 -80.78)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS", "is_usap_dc": false, "keywords": "Antarctica; Methane; Carbon-14; Permeability; CO2; Firn Core; FIELD SURVEYS; Deuterium Excess; ice core density; GROUND-BASED OBSERVATIONS; LABORATORY; Firn Air; isotopes; Megadunes; ice cores; Not provided; FIELD INVESTIGATION", "locations": "Antarctica", "north": -80.78, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bauer, Rob; Albert, Mary R.; Severinghaus, Jeffrey P.", "platforms": "Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "NSIDC", "repositories": "NSIDC", "science_programs": null, "south": -80.78, "title": "How Thick Is the Convective Zone: A Study of Firn Air in the Megadunes Near Vostok, Antarctica", "uid": "p0000097", "west": 124.5}, {"awards": "0337933 Cole-Dai, Jihong; 0338363 Thiemens, Mark", "bounds_geometry": null, "dataset_titles": "Major Ion Concentrations in 2004 South Pole Ice Core", "datasets": [{"dataset_uid": "609542", "doi": "10.7265/N5HX19N8", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ion Chromatograph; South Pole", "people": "Cole-Dai, Jihong", "repository": "USAP-DC", "science_program": null, "title": "Major Ion Concentrations in 2004 South Pole Ice Core", "url": "https://www.usap-dc.org/view/dataset/609542"}], "date_created": "Fri, 11 Aug 2006 00:00:00 GMT", "description": "This award supports a collaborative study between South Dakota State University (SDSU) and University of California, San Diego (UCSD) to investigate the oxygen and sulfur isotope composition of sulfates from a number of large volcanic eruptions in the past 1000 years. The project aims to drill a number of shallow ice cores at South Pole and return them to SDSU and UCSD lab for chemical and isotope analysis. Preliminary results from measurements of isotopes in sulfate samples from several volcanic eruptions in Antarctic snow and ice indicate that isotopic composition of volcanic sulfate contains abundant valuable information on atmospheric chemical and dynamic processes that have not been previously investigated. One tentative conclusion is that mass-independently fractionated sulfur isotopes reveal that atmospheric photolysis of sulfur compounds occurs at longer UV wavelengths than those in the Archean atmosphere, possibly reflecting the atmospheric ozone and/or oxygen concentration. This suggests that isotopic composition of atmospheric sulfate may be used to understand the role of UV radiation in sulfur dioxide conversion in the atmosphere and to track the evolution (i.e., oxygenation) of the atmosphere and the origin of life on Earth. Other major research objectives include understanding what impact massive volcanic eruptions have on the oxidative capacity of the atmosphere, what oxidants and mechanisms are involved in the oxidation or conversion of volcanic sulfur dioxide to sulfate in the stratosphere and what isotopic criteria may be used to differentiate ice core signals of stratospheric eruptions from those of tropospheric eruptions. By providing educational and research opportunities to graduate and undergraduate students at both SDSU and UCSD, the proposed project will promote the integration of research and education and contribute to human resource development in science and engineering. The project will contribute to a proposed REU chemistry site program at SDSU. This collaboration will utilize the complementary strengths of both labs and promote exchange between the two institutions. International collaboration will enhance scientific cooperation between France and US.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Not provided; Ion Chromatograph; Ions; LABORATORY; GROUND-BASED OBSERVATIONS; NSIDC", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Cole-Dai, Jihong", "platforms": "Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Investigating Atmospheric Chemistry and Dynamics through Oxygen and Sulfur Isotopes in Volcanic Sulfate from South Pole Ice Cores", "uid": "p0000031", "west": null}, {"awards": "0230021 Sowers, Todd; 0230348 Dunbar, Nelia; 0230316 White, James", "bounds_geometry": "POINT(135.1333 -76.05)", "dataset_titles": "Mount Moulton Isotopes and Other Ice Core Data", "datasets": [{"dataset_uid": "609640", "doi": "10.7265/N5FT8J0N", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; EPICA Dome C; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Lake Vostok; Mount Moulton; Paleoclimate; Talos Dome; Taylor Dome", "people": "Popp, Trevor; White, James; Steig, Eric J.", "repository": "USAP-DC", "science_program": null, "title": "Mount Moulton Isotopes and Other Ice Core Data", "url": "https://www.usap-dc.org/view/dataset/609640"}], "date_created": "Tue, 01 Aug 2006 00:00:00 GMT", "description": "The summit crater of Mt. Moulton, in West Antarctica, contains a 600-m thick horizontally-exposed section of ice with intercalated tephra layers from nearby Mt Berlin. Argon-40/Argon-39 dating of the thick, near-source tephra indicates that the age of the horizontal ice section ranges between 15,000 and 492,000 years. Thus, the Mt Moulton site offers an unparalleled repository of ancient West Antarctic snow and trapped air that can be used to investigate West Antarctic climate over much of the past 500,000 years. The planar nature and consistent dips of the tephra layers suggests that, although the ice section has thinned, it is otherwise undeformed. The Mt. Moulton site was visited during the 1999/2000 field season, at which time a horizontal ice core representing approximately 400 meters of ice was collected, ranging in age from 15,000 to older than 480,000 years. In addition to this horizontal core, samples of ice at a range of depths were collected in order to test the quality of the climate record in the ice. Forty tephra layers intercalated in the ice were also collected in order to provide chronology for the ice section. The results of this first effort are extremely encouraging. Based on the d?18 O of ice, for example, there is clearly a useable record of past climate at Mt. Moulton extending back beyond 140,000 years. There is work to do, however, to realize the full potential of this horizontal ice core. The elemental and isotopic composition of trapped gases suggest some contamination with modern air, for example. As gas cross-dating of ice cores is the current standard by which climate records are intercompared, we need to understand why and how the gas record is compromised before adding Moulton to our arsenal of ice core paleoclimate records. This award supports a collaborative effort between three institutions with following objectives: 1) to evaluate more thoroughly the integrity of the climatic record through shallow drilling of the blue ice area, as well as the snow field upslope from the blue ice; 2) to improve the radioisotopic dating of specific tephra layers; 3) to obtain baseline information about modern snowfall deposition, mean annual temperature, and wind pumping around the summit of Mt. Moulton; and 4) to study how firn densification differs when surface accumulation changes from net accumulation to net ablation.", "east": 135.1333, "geometry": "POINT(135.1333 -76.05)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e ELECTRON MICROPROBES", "is_usap_dc": true, "keywords": "chronology; LABORATORY; Climate; Argon-40; 40Ar; AGDC-project; Argon-39; FIELD SURVEYS; Ice Core Gas Age; Ice Core; FIELD INVESTIGATION; Tephra; gas record; Mount Moulton; Not provided; 39Ar; Stratigraphy; Ice Core Depth; caldera ", "locations": "Mount Moulton", "north": -76.05, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "White, James; Popp, Trevor; Dunbar, Nelia; Sowers, Todd A.; Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.05, "title": "Collaborative Research: Refining a 500-kry Climate Record From the Moulton Blue Ice Field in West Antarctica", "uid": "p0000755", "west": 135.1333}, {"awards": "0230260 Bender, Michael; 0230448 Severinghaus, Jeffrey", "bounds_geometry": "POLYGON((-75.34 86.6,-68.742 86.6,-62.144 86.6,-55.546 86.6,-48.948 86.6,-42.35 86.6,-35.752 86.6,-29.154 86.6,-22.556 86.6,-15.958 86.6,-9.36 86.6,-9.36 83.618,-9.36 80.636,-9.36 77.654,-9.36 74.672,-9.36 71.69,-9.36 68.708,-9.36 65.726,-9.36 62.744,-9.36 59.762,-9.36 56.78,-15.958 56.78,-22.556 56.78,-29.154 56.78,-35.752 56.78,-42.35 56.78,-48.948 56.78,-55.546 56.78,-62.144 56.78,-68.742 56.78,-75.34 56.78,-75.34 59.762,-75.34 62.744,-75.34 65.726,-75.34 68.708,-75.34 71.69,-75.34 74.672,-75.34 77.654,-75.34 80.636,-75.34 83.618,-75.34 86.6))", "dataset_titles": "Firn Air Inert Gas and Oxygen Observations from Siple Dome, 1996, and the South Pole, 2001; Trapped Gas Composition and Chronology of the Vostok Ice Core", "datasets": [{"dataset_uid": "609311", "doi": "10.7265/N5P26W12", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochronology; Glaciers/Ice Sheet; Ice Core Records; Lake Vostok; Paleoclimate; Vostok; Vostok Ice Core", "people": "Bender, Michael; Suwa, Makoto", "repository": "USAP-DC", "science_program": null, "title": "Trapped Gas Composition and Chronology of the Vostok Ice Core", "url": "https://www.usap-dc.org/view/dataset/609311"}, {"dataset_uid": "609290", "doi": "10.7265/N5FJ2DQC", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciology; Paleoclimate; Siple Dome; Snow/Ice; South Pole", "people": "Battle, Mark; Severinghaus, Jeffrey P.; Bender, Michael", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Firn Air Inert Gas and Oxygen Observations from Siple Dome, 1996, and the South Pole, 2001", "url": "https://www.usap-dc.org/view/dataset/609290"}], "date_created": "Wed, 18 Jan 2006 00:00:00 GMT", "description": "High latitude deep ice cores contain fundamental records of polar temperatures, atmospheric dust loads (and continental aridity), greenhouse gas concentrations, the status of the biosphere, and other essential properties of past environments. An accurate chronology for these records is needed if their significance is to be fully realized. The dating challenge has stimulated efforts at orbital tuning. In this approach, one varies a timescale, within allowable limits, to optimize the match between a paleoenvironmental property and a curve of insolation through time. The ideal property would vary with time due to direct insolation forcing. It would be unaffected by complex climate feedbacks and teleconnections, and it would give a clean record with high signal/noise ratio. It is argued strongly that the O2/N2 ratio of ice core trapped gases is such a property, and evidence is presented that this property, whose atmospheric ratio is nearly constant, is tied to local summertime insolation. This award will support a project to analyze the O2/N2 ratios at 1 kyr intervals from ~ 115-400 ka in the Vostok ice core. Ancillary measurements will be made of Ar/N2, and Ne/N2 and heavy noble gas ratios, in order to understand bubble close-off fractionation and its manifestation in the Vostok trapped gas record. O2/N2 variations will be matched with summertime insolation at Vostok to achieve a high-accuracy chronology for the Vostok core. The Vostok and other correlatable climate records will then be reexamined to improve our understanding of the dynamics of Pleistocene climate change.", "east": 106.8, "geometry": "POINT(106.8 -72.4667)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Paleoclimate; Siple Dome; Ice Age; Shallow Firn Air; Firn Air Isotope Measurements; noble gases; Polar Firn Air; Oxygen Isotopes; Ice Core Gas Records; Atmospheric Gases; Trapped Gases; Not provided; LABORATORY; Vostok; Firn Air Isotopes; ice sample gas integrity; Thermal Fractionation; Ice Core Chemistry; Trapped Air Bubbles; Ice Core; Antarctica; South Pole; Ice Core Data; GROUND-BASED OBSERVATIONS; Gas Age; Firn Isotopes", "locations": "Antarctica; Vostok; Siple Dome; South Pole", "north": -72.4667, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Battle, Mark; Bender, Michael; Suwa, Makoto; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -72.4667, "title": "Collaborative Research: Trapped Gas Composition and the Chronology of the Vostok Ice Core", "uid": "p0000257", "west": 106.8}, {"awards": "0125276 Albert, Mary; 0125570 Scambos, Ted", "bounds_geometry": null, "dataset_titles": "Access AGDC data online by navigating to Data Sets. Data sets are arranged by Principal Investigators. Access data that are combined into multiple data sets, or compiled products.; AWS Data: Characteristics of Snow Megadunes and Their Potential Effect on Ice Core Interpretation; GPR and GPS Data: Characteristics of Snow Megadunes and their Potential Effects on Ice Core Interpretation; Snow and Firn Permeability: Characteristics of Snow Megadunes and their Potential Effects on Ice Core Interpretation; The Antarctic Glaciological Data Center (AGDC) at the National Snow and Ice Data Center (NSIDC) archives and distributes Antarctic glaciological and cryospheric system data collected by the U.S. Antarctic Program.", "datasets": [{"dataset_uid": "609299", "doi": "10.7265/N5639MPD", "keywords": "Antarctica; Cryosphere; East Antarctic Plateau; Glaciology; Physical Properties; Snow/Ice", "people": "Courville, Zoe; Cathles, Mac; Albert, Mary R.", "repository": "USAP-DC", "science_program": null, "title": "Snow and Firn Permeability: Characteristics of Snow Megadunes and their Potential Effects on Ice Core Interpretation", "url": "https://www.usap-dc.org/view/dataset/609299"}, {"dataset_uid": "001669", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "Access AGDC data online by navigating to Data Sets. Data sets are arranged by Principal Investigators. Access data that are combined into multiple data sets, or compiled products.", "url": "http://nsidc.org/data/agdc_investigators.html"}, {"dataset_uid": "001343", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "The Antarctic Glaciological Data Center (AGDC) at the National Snow and Ice Data Center (NSIDC) archives and distributes Antarctic glaciological and cryospheric system data collected by the U.S. Antarctic Program.", "url": "https://nsidc.org/data/agdc/"}, {"dataset_uid": "609282", "doi": "10.7265/N5Q23X5F", "keywords": "Antarctica; Cryosphere; East Antarctic Plateau; Glaciology; GPS; Ground Penetrating Radar; Navigation; Paleoclimate; Snow/Ice", "people": "Bauer, Rob; Scambos, Ted", "repository": "USAP-DC", "science_program": null, "title": "GPR and GPS Data: Characteristics of Snow Megadunes and their Potential Effects on Ice Core Interpretation", "url": "https://www.usap-dc.org/view/dataset/609282"}, {"dataset_uid": "609283", "doi": "10.7265/N5K935F3", "keywords": "Antarctica; Atmosphere; Cryosphere; East Antarctic Plateau; Glaciers/Ice Sheet; Meteorology; Snow/Ice", "people": "Bauer, Rob; Scambos, Ted; Fahnestock, Mark; Haran, Terry", "repository": "USAP-DC", "science_program": null, "title": "AWS Data: Characteristics of Snow Megadunes and Their Potential Effect on Ice Core Interpretation", "url": "https://www.usap-dc.org/view/dataset/609283"}], "date_created": "Wed, 04 Jan 2006 00:00:00 GMT", "description": "This award supports a program of field surveys of an area within the large, well-developed megadune field southeast of Vostok station. The objectives are to determine the physical characteristics of the firn across the dunes, including typical climate indicators such as stable isotopes and major chemical species, and to install instruments to measure the time variation of near-surface wind and temperature with depth, to test and refine hypotheses for megadune formation. Field study will consist of surface snowpit and shallow core sampling, ground penetrating radar (GPR) profiling, GPS topographic and ice motion surveys, AWS installation, accumulation/ ablation measurements, subsurface temperature, and firn permeability studies. Field work in two successive seasons is proposed. Continent-wide remote sensing studies of the dunes will be continued, using the new group of instruments that are now, or will shortly be available (e.g., MODIS, MISR, GLAS, AMSR). The earlier study of topographic, passive microwave, and SAR characteristics will be extended, with the intent of determining the relationships of dune amplitude and wavelength to climate parameters, and further development of models of dune formation. Diffusion, ventilation, and vapor transport processes within the dune firn will be modeled as well. A robust program of outreach is planned and reporting to inform both the public and scientists of the fundamental in-situ and remote sensing characteristics of these uniquely Antarctic features will be an important part of the work. Because of their extreme nature, their broad extent, and their potential impact on the climate record, it is important to improve our current understanding of these. Megadunes are a manifestation of an extreme terrestrial climate and may provide insight on past terrestrial climate, or to processes active on other planets. Megadunes are likely to represent an end-member in firn diagenesis, and as such, may have much to teach us about the processes involved.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e PERMEAMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; IN SITU/LABORATORY INSTRUMENTS \u003e CURRENT/WIND METERS \u003e ANEMOMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ICE AUGERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e SNOWPACK TEMPERATURE PROBE; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e SAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e AIR PERMEAMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CURRENT/WIND METERS \u003e ANEMOMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e RADIO \u003e ARGOS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMOMETERS \u003e THERMOMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e WIND PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e DENSIOMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e GAUGES \u003e BALANCE", "is_usap_dc": true, "keywords": "ICESAT; Antarctic; Wind Speed; FIELD INVESTIGATION; Surface Morphology; Antarctica; GROUND-BASED OBSERVATIONS; ARWS; Polar Firn Air; Microstructure; Gas Diffusivity; WEATHER STATIONS; Surface Temperatures; RADARSAT-2; Ice Core; Wind Direction; AWS; Ice Sheet; Megadunes; GROUND STATIONS; METEOROLOGICAL STATIONS; thermal conductivity; Antarctic Ice Sheet; AGDC; Density; Air Temperatures; Snow Pits; Atmospheric Pressure; climate record; Internal layering; Firn Permeability; FIELD SURVEYS; Radar; Permeability; Firn Temperature Measurements; Snow Megadunes; Paleoenvironments; sublimation; LANDSAT; Firn; vapor-redeposition; Ice Core Interpretation; East Antarctic Plateau; Not provided; Surface Winds; ice climate record; Snow Density; field survey; Glaciology; dunefields; Snow Permeability; Automated Weather Stations", "locations": "Antarctica; Antarctic Ice Sheet; Antarctic; East Antarctic Plateau", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Courville, Zoe; Cathles, Mac; Scambos, Ted; Bauer, Rob; Fahnestock, Mark; Haran, Terry; Shuman, Christopher A.; Albert, Mary R.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e ARWS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e METEOROLOGICAL STATIONS; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e ICE, CLOUD AND LAND ELEVATION SATELLITE (ICESAT) \u003e ICESAT; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e LANDSAT \u003e LANDSAT; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e RADARSAT \u003e RADARSAT-2; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e WEATHER STATIONS", "repo": "USAP-DC", "repositories": "NSIDC; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Characteristics of Snow Megadunes and Their Potential Effect on Ice Core Interpretation", "uid": "p0000587", "west": null}, {"awards": "0125761 Thiemens, Mark", "bounds_geometry": null, "dataset_titles": "Atmospheric Nitrate Isotopic Analysis at Amundsen-Scott South Pole Station, A Twenty-Five Year Record", "datasets": [{"dataset_uid": "609281", "doi": "10.7265/N5TT4NWF", "keywords": "Aerosol; Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; NBP1502; Snow/Ice; South Pole Station", "people": "Thiemens, Mark H.; Savarino, Joel", "repository": "USAP-DC", "science_program": null, "title": "Atmospheric Nitrate Isotopic Analysis at Amundsen-Scott South Pole Station, A Twenty-Five Year Record", "url": "https://www.usap-dc.org/view/dataset/609281"}], "date_created": "Tue, 27 Dec 2005 00:00:00 GMT", "description": "This award supports a detailed laboratory analysis of the mass-independent isotopic composition of processes associated with atmospheric nitrate trapped in the snow pack at the South Pole. The project will specifically test if the oxygen isotopes 16O, 17O, 18O of nitrate can be used to probe the denitrification of the Antarctic stratosphere. Despite decades of research, there are several important issues in Antarctic atmospheric science, which are presently inadequately resolved. This includes quantification over time of the sources of nitrate aerosols. Today, little is known about the past denitrification of the stratosphere in high latitude regions. This lack of knowledge significantly limits our ability to understand the chemical state of ancient atmospheres and therefore evaluate present and past-coupled climate/atmosphere models. The role of nitrogen in environmental degradation is well known. This issue will also be addressed in this proposal. Atmospheric aerosols have now been shown to possess a mass-independent oxygen isotopic content. The proposed research will investigate the stable oxygen isotope ratios of nitrate in Antarctica both collected in real time and from the snow. Two periods of time will be covered. Full year nitrate aerosol collections, with week resolution time horizons, will be performed at the South Pole. Weekly aerosol collections will help us to identify any seasonal trend of the oxygen-17 excess anomaly, and eventually link this anomaly to the denitrification of the Antarctic stratosphere. This data set will also be used to test our assumption that the oxygen isotopic anomaly of nitrate is mainly formed in the stratosphere and is well preserved in the snow pack. If true, we will for the first time resolve an atmospheric signal extracted from a nitrate profile. The snow pit will allow us to see any trend in the data on a multiple decade timescale.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "AGDC; Snow; GROUND STATIONS; Ion Chemistry; South Pole; Aerosols; Not provided; Oxygen Isotopes; GROUND-BASED OBSERVATIONS; Snow Pit; Antarctica; Admundsen-Scott Station", "locations": "Antarctica; South Pole", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Savarino, Joel; Thiemens, Mark H.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "South Pole Atmospheric Nitrate Isotopic Analysis (SPANIA)", "uid": "p0000242", "west": null}, {"awards": "0125900 Sowers, Todd", "bounds_geometry": "POINT(-148.8 -81.7)", "dataset_titles": null, "datasets": null, "date_created": "Thu, 26 May 2005 00:00:00 GMT", "description": "0125900\u003cbr/\u003eSowers\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to improve the understanding of the biogeochemical processes that control CH4 emissions. Records of the concentration of methane in trapped gases in ice tell us about changes in atmospheric loading through time. Such records do not, however, provide information on the individual sources or sinks. One way to refine our understanding of the cycling of bioactive trace gases like methane is to use stable isotope records of trapped gases in ice cores. This project will measure the Deuterium/Hydrogen (D/H) ratio of methane trapped in shallow/recent ice (covering the last ~ 200 years) at Siple Dome, Antarctica. The proposed work will complement current efforts to measure the carbon-13 isotope ratio of methane in ice cores and will provide fundamental information on the various sources and sinks of atmospheric methane over the last 200 years.", "east": -148.8, "geometry": "POINT(-148.8 -81.7)", "instruments": null, "is_usap_dc": false, "keywords": "Siple Dome; Not provided; CH4; Methane; Antarctica; Ice Core", "locations": "Siple Dome; Antarctica", "north": -81.7, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Sowers, Todd A.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -81.7, "title": "Constructing the first D/H record of atmospheric methane covering the last two centuries.", "uid": "p0000754", "west": -148.8}, {"awards": "0125981 Sowers, Todd", "bounds_geometry": "POLYGON((-180 -62.83,-144 -62.83,-108 -62.83,-72 -62.83,-36 -62.83,0 -62.83,36 -62.83,72 -62.83,108 -62.83,144 -62.83,180 -62.83,180 -65.547,180 -68.264,180 -70.981,180 -73.698,180 -76.415,180 -79.132,180 -81.849,180 -84.566,180 -87.283,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.283,-180 -84.566,-180 -81.849,-180 -79.132,-180 -76.415,-180 -73.698,-180 -70.981,-180 -68.264,-180 -65.547,-180 -62.83))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 05 May 2005 00:00:00 GMT", "description": "0125981\u003cbr/\u003eSowers\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to construct an isotopic record of atmospheric methane and nitrous oxide over the last century from South Pole firn air. Over the last 150 years, atmospheric methane and nitrous oxide concentrations have risen in response to increased emissions from various anthropogenic activities. As this trend is liable to continue in the foreseeable future, it is important to understand the biogeochemical processes that contribute to the emissions of these two greenhouse gases. In this context, records of the variations in the atmospheric loading of trace gases found in ice cores and interstitial spaces in the snow near the surface of the ice sheet (firn air) provide fundamental boundary conditions for reconstructing historical emission records. One way to improve our understanding of the cycling of bioactive trace gases and their emission records is to use stable isotope tracers, which have been recorded in the ice cores and firn air. This project will develop records of carbon-13 and deuterium isotope ratios of methane, as well as the nitrogen-15, oxygen-18 and the isotopomer composition of nitrous oxide trapped in firn air samples collected in January 2001 at the South Pole. These measurements will allow isotopic records of these atmospheric gases to be reconstructed throughout the 20th century. Such records will help to establish the relative contribution of individual sources with a higher degree of confidence than is currently available.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -62.83, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Sowers, Todd A.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -90.0, "title": "Generating an Isotopic Record of Atmospheric Methane and Nitrous Oxide Over the Last Century from South Pole Firn Air", "uid": "p0000086", "west": -180.0}, {"awards": "0088054 Goldstein, Steven", "bounds_geometry": "POLYGON((-180 -39.57,-144 -39.57,-108 -39.57,-72 -39.57,-36 -39.57,0 -39.57,36 -39.57,72 -39.57,108 -39.57,144 -39.57,180 -39.57,180 -42.967,180 -46.364,180 -49.761,180 -53.158,180 -56.555,180 -59.952,180 -63.349,180 -66.746,180 -70.143,180 -73.54,144 -73.54,108 -73.54,72 -73.54,36 -73.54,0 -73.54,-36 -73.54,-72 -73.54,-108 -73.54,-144 -73.54,-180 -73.54,-180 -70.143,-180 -66.746,-180 -63.349,-180 -59.952,-180 -56.555,-180 -53.158,-180 -49.761,-180 -46.364,-180 -42.967,-180 -39.57))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 26 Apr 2005 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the sediment core from the Southern Ocean for paleoenvironmental research. The polar regions are susceptible to the largest changes in climate and are among the least accessible places on Earth. Current concern about the instability of the West Antarctic Ice Sheet has heightened awareness of the vulnerability of polar regions. This proposal seeks to gain a basic understanding of the isotopic characteristics of terrigenous sediment sources derived from Antarctica in the Holocene and Last Glacial Maximum, and their dispersal into the Southern Ocean. Terrigenous clastic sediments are brought to the ocean from continental sources via rivers, ice and wind, and distributed within the ocean by surface and deep currents. At present there are virtually no isotopic data on circumpolar detritus, save a few strontium (Sr) isotopic ratios in the Atlantic sector. This project will fill part of this gap. From the large range in geological ages of crustal provinces of Antarctica, we would predict that there are large isotopic differences in detritus around the continent. The main objectives are to (1) characterize the strontium-neodymium-lead-argon (Sr-Nd-Pb-Ar) isotope compositions of sediment sources derived from Antarctica, (2) to identify the composition and source ages of major ice rafted detritus (IRD) contributions by analyzing individual grains of hornblende and feldspar in conjunction with bulk isotopic analysis, and (3) track sediment dispersal into the Antarctic Circumpolar Current (ACC) during the Holocene and Last Glacial Maximum.\u003cbr/\u003e\u003cbr/\u003eBecause of the paucity of circumpolar data, this research necessarily has a large exploratory component. Consequently, it will provide a basic database for future studies. Nevertheless there are important hypothesis-driven questions that will be addressed in this primary pass. Can lessons learned in North Atlantic IRD studies be applied toward understanding the history of Antarctic ice sheets? Can the large geological variability around the Antarctic margin be treated as a series of natural tracer injections into the ACC, and thus characterize its trajectory, speed, and interaction with other current systems today and in the past? The proposed study is motivated by an exciting set of results from the South Atlantic, showing that detrital Sr isotope ratios are a sensitive current tracer in that region. This research should serve a basic need across many Earth Science disciplines if the use of long-lived radiogenic isotopes (Sr-Nd-Pb-Ar) as tracers of marine sediment sources is successful in elucidating processes related to changing climatic conditions. The results of this study will fill a basic gap in our knowledge of an important region of the Earth. At the same time, it will provide an essential basis for attempting reconstruction of the ACC during the LGM, as well as for future studies of Antarctic geology, ice sheet history, and the Southern Ocean circulation.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -39.57, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Roy, Martin; Hemming, Sidney R.; Goldstein, Steven L.; Van De Flierdt, Christina-Maria", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -73.54, "title": "Establishing the Pattern of Holocene-LGM Changes in Sediment Contributions from Antarctica to the Southern Ocean", "uid": "p0000724", "west": -180.0}, {"awards": "0125468 Severinghaus, Jeffrey", "bounds_geometry": "POLYGON((-180 -62.83,-144 -62.83,-108 -62.83,-72 -62.83,-36 -62.83,0 -62.83,36 -62.83,72 -62.83,108 -62.83,144 -62.83,180 -62.83,180 -65.547,180 -68.264,180 -70.981,180 -73.698,180 -76.415,180 -79.132,180 -81.849,180 -84.566,180 -87.283,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.283,-180 -84.566,-180 -81.849,-180 -79.132,-180 -76.415,-180 -73.698,-180 -70.981,-180 -68.264,-180 -65.547,-180 -62.83))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 01 Feb 2005 00:00:00 GMT", "description": "This award supports the continued measurements of gas isotopes in the Vostok ice core, from Antarctica. One objective is to identify the phasing of carbon dioxide variations and temperature variations, which may place constraints on hypothesized cause and effect relationships. Identification of phasing has in the past been hampered by the large and uncertain age difference between the gases trapped in air bubbles and the surrounding ice. This work will circumvent this issue by employing an indicator of temperature in the gas phase. It is argued that 40Ar/39Ar behaves as a qualitative indicator of temperature, via an indirect relationship between temperature, accumulation rate, firn thickness, and gravitational fractionation of the gas isotopes. The proposed research will make nitrogen and argon isotope measurements on ~ 200 samples of ice covering Termination II (130,000 yr B.P.) and Termination IV (340,000 yr BP). The broader impacts may include a better understanding of the role of atmospheric carbon dioxide concentrations in climate change.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "Vostok; Isotope; Ice Core; Not provided", "locations": "Vostok", "north": -62.83, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -90.0, "title": "Argon and nitrogen isotope measurements in the Vostok ice core as aconstraint on phasing of CO2 and temperature changes", "uid": "p0000752", "west": -180.0}, {"awards": "XXXXXXX Palais, Julie", "bounds_geometry": null, "dataset_titles": "Talos Dome Ice Core Deuterium Isotope Data", "datasets": [{"dataset_uid": "609252", "doi": "", "repository": "USAP-DC", "science_program": null, "title": "Talos Dome Ice Core Deuterium Isotope Data", "url": "http://www.usap-dc.org/view/dataset/609252"}], "date_created": "Fri, 27 Aug 2004 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; Talos Dome", "locations": "Talos Dome; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Jouzel, Jean; Stenni, Barbara", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "XXXXXXX Palais, Julie", "bounds_geometry": null, "dataset_titles": "Vostok Ice Core Chemistry, Timescale, Isotope, and Temperature Data", "datasets": [{"dataset_uid": "609242", "doi": "", "repository": "USAP-DC", "science_program": null, "title": "Vostok Ice Core Chemistry, Timescale, Isotope, and Temperature Data", "url": "http://www.usap-dc.org/view/dataset/609242"}], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Isotope; Lake Vostok; Paleoclimate; Physical Properties; Temperature; Vostok Ice Core", "locations": "Lake Vostok; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Sowers, Todd A.; Petit, Jean Robert; Jouzel, Jean; Fishcer, Hubertus; Bender, Michael; Chappellaz, Jerome; Lal, Devendra; Raymo, Maureen; Lorius, Claude; Brook, Edward J.; Blunier, Thomas; Ruddiman, William; Barnola, J. M.", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "9316564 Mayewski, Paul", "bounds_geometry": null, "dataset_titles": "Ross Ice Drainage System (RIDS) Glaciochemical Analysis; Siple Dome Ice Core Chemistry and Ion Data", "datasets": [{"dataset_uid": "609251", "doi": "", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Blunier, Thomas; Severinghaus, Jeffrey P.; Dunbar, Nelia; Mayewski, Paul A.; Kreutz, Karl; Brook, Edward J.", "repository": "NCEI", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Ice Core Chemistry and Ion Data", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/2461"}, {"dataset_uid": "609266", "doi": "10.7265/N5M906KG", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Snow/Ice; Snow Pit", "people": "Kreutz, Karl; Twickler, Mark; Meeker, Loren D.; Mayewski, Paul A.; Whitlow, Sallie", "repository": "USAP-DC", "science_program": null, "title": "Ross Ice Drainage System (RIDS) Glaciochemical Analysis", "url": "https://www.usap-dc.org/view/dataset/609266"}], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": "9316564 Mayewski This award is for support for a three year program to provide a high resolution record of the Antarctic climate through the acquisition, analysis, and interpretation of records of atmospheric chemical deposition taken from three ice cores located at sites within or immediately adjacent to the Ross Ice Drainage System (RIDS). These cores include one from Taylor Dome, and two from West Antarctic locations identified as potential deep drilling sites for the WAISCORES program. Collection of the two West Antarctic cores is intended to be a lightweight dry-drilling operation to depths of ~ 200 m, which will provide records of \u003e 2 kyr. Glaciochemical analyses will focus on the major cations and anions found in the antarctic atmosphere, plus methanesulfonic acid and selected measurements of the hydrogen ion, aluminum, iron, and silica. These analyses, and companion stable isotope and particle measurements to be carried out by other investigators require \u003c 7% by volume of each core, leaving \u003e 90% for other investigators and storage at the U.S. National Ice Core Laboratory. These records are intended to solve a variety of scientific objectives while also providing spatial sampling and reconnaissance for future U.S. efforts in West Antarctica. ***", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Magnesium; Nitrate (NO3); NSIDC \u003e National Snow and Ice Data Center; AGDC; Calcium (CA); GROUND STATIONS; Methane Sulfonic Acid; Ice Core Chemistry; Ammonium (NH4); Sulfate (SO4); Potassium (K); Ice Core; Sodium (Na); Chloride (CL)", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kreutz, Karl; Twickler, Mark; Whitlow, Sallie; Blunier, Thomas; Dunbar, Nelia; Brook, Edward J.; Mayewski, Paul A.; Meeker, Loren D.; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "NCEI", "repositories": "NCEI; USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Ross Ice Drainage System (RIDS) Late Holocene Climate Variability", "uid": "p0000145", "west": null}, {"awards": "9714687 Brook, Edward", "bounds_geometry": null, "dataset_titles": "Byrd Ice Core Microparticle and Chemistry Data", "datasets": [{"dataset_uid": "609247", "doi": "", "keywords": "Antarctica; Byrd; Byrd Ice Core; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate", "people": "Blunier, Thomas; Brook, Edward J.; Fluckiger, Jacqueline; Thompson, Lonnie G.", "repository": "USAP-DC", "science_program": "Byrd Ice Core", "title": "Byrd Ice Core Microparticle and Chemistry Data", "url": "https://www.usap-dc.org/view/dataset/609247"}], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": "This award is for support for a program to make high resolution studies of variations in the concentration of methane, the oxygenisotope composition of paleoatmospheric oxygen, and the total gas content of deep Antarctic ice cores. Studies of the concentration and isotopic composition of air in the firn of the Antarctic ice sheet will also be continued. One objective of this work is to use the methane concentration and oxygen-isotope composition of oxygen of air in ice as time-stratigraphic markers for the precise intercorrelation of Greenland and Antarctic ice cores as well as the correlation of ice cores to other climatic records. A second objective is to use variations in the concentration and interhemispheric gradient of methane measured in Greenland and Antarctic ice cores to deduce changes in continental climates and biogeochemistry on which the atmospheric methane distribution depends. A third objective is to use data on the variability of total gas content in the Siple Dome ice core to reconstruct aspects of the glacial history of West Antarctica during the last glacial maximum. The fourth objective is to participate in collaborative studies of firn air chemistry at Vostok, Siple Dome, and South Pole which will yield much new information about gas trapping in ice as well as the concentration history and isotopic composition of greenhouse gases, oxygen, trace biogenic gases and trace anthropogenic gases during the last 100 years.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "GROUND STATIONS", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Blunier, Thomas; Fluckiger, Jacqueline; Thompson, Lonnie G.; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Studies of Trapped Gases in Firn and Ice from Antarctic Deep Ice Cores", "uid": "p0000168", "west": null}, {"awards": "0126286 McConnell, Joseph", "bounds_geometry": "POLYGON((-180 -62.83,-144 -62.83,-108 -62.83,-72 -62.83,-36 -62.83,0 -62.83,36 -62.83,72 -62.83,108 -62.83,144 -62.83,180 -62.83,180 -65.547,180 -68.264,180 -70.981,180 -73.698,180 -76.415,180 -79.132,180 -81.849,180 -84.566,180 -87.283,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.283,-180 -84.566,-180 -81.849,-180 -79.132,-180 -76.415,-180 -73.698,-180 -70.981,-180 -68.264,-180 -65.547,-180 -62.83))", "dataset_titles": "Siple Shallow Core Density Data", "datasets": [{"dataset_uid": "609129", "doi": "10.7265/N52F7KCD", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Lamorey, Gregg W.", "repository": "USAP-DC", "science_program": null, "title": "Siple Shallow Core Density Data", "url": "https://www.usap-dc.org/view/dataset/609129"}], "date_created": "Mon, 19 Apr 2004 00:00:00 GMT", "description": "This award provides one year of support to use newly developed technology in which an ice-core melter is coupled with both an Inductively Coupled Plasma - Mass Spectrometer (ICP-MS) and a traditional Continuous Flow Analysis (CFA) system, to measure a continuous time series of chemical and trace element deposition on the Siple Dome ice core from West Antarctica. A coupled ice-core melter, ICP-MS, and CFA system will be used to measure concentrations of a number of elements, isotopes and chemical species at very high depth resolution (~2-cm) in the top 54 m of the Siple Dome A-core. Pilot data from analyses of ~6 m from the nearby but much lower accumulation J-core site at Siple Dome, together with more extensive results from Summit, Greenland, indicate that it will be possible to obtain exactly co-registered, high-quality records of at least 12 seasonally varying elements (sodium, magnesium, aluminum, potassium, calcium, iron, manganese, rubidium, strontium, zirconium, barium, lead) and three other chemical species and ions (ammonium, nitrate, calcium ion) with this system. Under this proposed research, we will also add continuous measurements of sulfate to our system. Because more than sufficient core from Siple Dome for these depths is archived at the National Ice Core Laboratory, the proposed research will require no fieldwork. The continuous, very high-resolution, ~350-y record of these elemental tracers will enhance the value of previous chemical and isotopic measurements that have been made on the Siple Dome core and will be particularly valuable for comparisons between ice-core proxies and modern instrumental data related to El Nino-Southern Oscillation (ENSO) as well as for validation of model simulations of atmospheric circulation. These data, and the expertise gained through this research, will be invaluable when this novel chemical analysis technology is eventually applied to deep ice-core records for the study of rapid climate-change events.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "WAISCORES; shallow core; Siple Coast; Glaciology; Not provided; GROUND-BASED OBSERVATIONS; Ice Core; Siple; Antarctica; Density; NSIDC; Snow; Ice Sheet; Siple Dome; GROUND STATIONS; Stratigraphy", "locations": "Antarctica; Siple Coast; Siple Dome", "north": -62.83, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Lamorey, Gregg W.; McConnell, Joseph", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -90.0, "title": "Continuous High Resolution Ice-Core Chemistry using ICP-MS at Siple Dome", "uid": "p0000159", "west": -180.0}, {"awards": "9980691 Wahlen, Martin", "bounds_geometry": null, "dataset_titles": "Atmospheric CO2 Trapped in the Ice Core from Siple Dome, Antarctica", "datasets": [{"dataset_uid": "609202", "doi": "10.7265/N5N877Q9", "keywords": "Antarctica; Chemistry:Fluid; CO2; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Ahn, Jinho; Deck, Bruce; Wahlen, Martin", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Atmospheric CO2 Trapped in the Ice Core from Siple Dome, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609202"}], "date_created": "Thu, 11 Dec 2003 00:00:00 GMT", "description": "9980691\u003cbr/\u003eWahlen\u003cbr/\u003e\u003cbr/\u003eThis award is for support for three years of funding to reconstruct the atmospheric carbon dioxide (CO2) and carbon-13 isotope (d13C) concentration in ice cores from Antarctica over several climatic periods. Samples from the Holocene, the Last Glacial Maximum (LGM)-Holocene transition and glacial stadial/interstadial episodes will be examined. Samples from the Siple Dome ice core drilled in 1998/99 will be made, in addition to measurements from the Taylor Dome and Vostok ice cores. The major objectives are to investigate the phase relationships between variations in the concentration of atmospheric CO2, its carbon isotope composition, and temperature changes (indicated by 18dO and dD of the ice) during deglaciations as well as across rapid climate change events (e.g. Dansgaard-Oeschger events). This will help to determine systematic changes in the global carbon cycle during and between different climatic periods, and to ascertain if the widely spread northern hemisphere temperature stadial/interstadial events produced a global atmospheric carbon dioxide signal. Proven experimental techniques will be used.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "FIELD SURVEYS; Siple Dome; Ice Core; USAP-DC; Carbon Dioxide", "locations": "Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Wahlen, Martin; Ahn, Jinho; Deck, Bruce", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "CO2 and Delta 13CO2 in Antarctic Ice Cores", "uid": "p0000166", "west": null}, {"awards": "XXXXXXX Palais, Julie", "bounds_geometry": null, "dataset_titles": "Siple Dome Highlights: Stable isotopes", "datasets": [{"dataset_uid": "609134", "doi": "10.7265/N59021PM", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Highlights: Stable isotopes", "url": "http://www.usap-dc.org/view/dataset/609134"}], "date_created": "Mon, 18 Aug 2003 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Paleoclimate; Siple Dome; Siple Dome Ice Core; WAISCORES", "locations": "Siple Dome; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.; White, James", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": null, "uid": null, "west": null}, {"awards": "XXXXXXX Palais, Julie", "bounds_geometry": null, "dataset_titles": "Taylor Dome Ice Core Data", "datasets": [{"dataset_uid": "609132", "doi": "10.7265/N5JH3J4C", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Taylor Dome Ice Core Data", "url": "http://www.usap-dc.org/view/dataset/609132"}], "date_created": "Mon, 18 Aug 2003 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "locations": "Taylor Dome; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.; White, James", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": null, "title": null, "uid": null, "west": null}, {"awards": "9977306 Ryan, Jeffrey", "bounds_geometry": "POINT(167.16 -77.5)", "dataset_titles": "B-Be-Li Abundance and Isotope Data: Mt. Erebus-McMurdo Volcanics", "datasets": [{"dataset_uid": "600020", "doi": "", "keywords": null, "people": "Ryan, Jeffrey", "repository": "USAP-DC", "science_program": null, "title": "B-Be-Li Abundance and Isotope Data: Mt. Erebus-McMurdo Volcanics", "url": "https://www.usap-dc.org/view/dataset/600020"}], "date_created": "Thu, 19 Jun 2003 00:00:00 GMT", "description": "Subduction zones are the one place on Earth where materials from the surface (water, sediments and crustal rocks) can be carried into our planet\u0027s deep interior. To quantify this process of subduction-zone recycling, we need to understand both the input of sediments and crust to trenches, and all geochemical outputs related to the subduction process. While the chemical outputs represented by magmatism at volcanic arcs and in back-arc settings have been widely studied, little is known about possible subduction-related outfluxes through the shallow forearc, between the arc and the trench. We are attempting to characterize the \"forearc flux\" by examining serpentinites which are rising diapirically through the forearc mantle and crust in the Mariana arc-trench system. Our work will complete efforts begun (with NSF support) several years ago, and will characterize these samples (and the slab-derived fluids which helped to create them) for radiogenic isotopes, lithium and oxygen isotopes, and the \"fluid-mobile\" elements Cs, Rb, U, As, Pb, and Sb. Our work will allow us to characterize both the chemical inventories of species that are released from subducting slabs beneath forearcs, and the magnitude of this flux, for comparison with results for trench inputs (being collected as part of ODP Leg 125), and existing data for arc volcanic outputs in the Mariana system.", "east": 167.16, "geometry": "POINT(167.16 -77.5)", "instruments": null, "is_usap_dc": false, "keywords": "MT. EREBUS; McMurdo Volcanic Group; Not provided; Crary Mountains; NSF", "locations": null, "north": -77.5, "nsf_funding_programs": "Marine Geology and Geophysics", "paleo_time": null, "persons": "Ryan, Jeffrey", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.5, "title": "The Role of the Forearc in Subduction Zone Chemical Cycles: Elemental and Isotopic Signatures of Forearc Serpentinites, ODP Leg 125", "uid": "p0000244", "west": 167.16}, {"awards": "9526979 White, James", "bounds_geometry": null, "dataset_titles": "Siple Dome Core Date from Measurement of the d18O of Paleoatmospheric Oxygen", "datasets": [{"dataset_uid": "609123", "doi": "10.7265/N5TX3C95", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "White, James; Bender, Michael", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Core Date from Measurement of the d18O of Paleoatmospheric Oxygen", "url": "https://www.usap-dc.org/view/dataset/609123"}], "date_created": "Mon, 16 Jun 2003 00:00:00 GMT", "description": "This award is for support for a program to measure the stable isotope (deuterium to hydrogen and oxygen-18 to oxygen-16) concentrations of ice cores retrieved from Siple Dome as part of the West Antarctic ice sheet program. In addition, the deuterium excess of samples from the Taylor Dome ice core will be determined. This project will approach the question of rapid climate change using ice cores to determine the history of temperature changes, moisture source changes, and elevational changes in the West Antarctic ice sheet. Results from ice cores taken to date in the interior of Antarctica (East and West) are surprisingly lacking in indications of abrupt climate changes, such as those that have been observed in the GISP2 ice core from Summit, Greenland. This work will address the question of whether rapid climate changes, which are known to have occurred in other parts of the southern hemi-sphere, may have also occurred in the coastal regions of West Antarctica. There is some indication from existing records of isotopes in ice cores that the West Antarctic ice sheet may have flushed ice in the past (as evidenced by large changes in elevation of the ice sheet).", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Antarctica; LABORATORY; WAISCORES; GROUND STATIONS; Siple Coast; Glaciology; Snow; isotopes; d18O; thermometry; NSIDC; Ice Sheet; Siple; Accumulation; Ice Core; Siple Dome; Stratigraphy; Densification; GROUND-BASED OBSERVATIONS; Not provided", "locations": "Antarctica; Siple Coast; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "White, James; Bender, Michael", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; 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": "Isotopic Measurements on the WAIS/Siple Dome Ice Cores", "uid": "p0000063", "west": null}, {"awards": "9615347 Conway, Howard", "bounds_geometry": null, "dataset_titles": "Roosevelt Island Bedrock and Surface Elevations; Roosevelt Island Ice Core Density and Beta Count Data", "datasets": [{"dataset_uid": "609139", "doi": "10.7265/N55718ZW", "keywords": "Antarctica; Beta Count; Cryosphere; Density; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; Roosevelt Island", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Ice Core Density and Beta Count Data", "url": "https://www.usap-dc.org/view/dataset/609139"}, {"dataset_uid": "609140", "doi": "10.7265/N51J97NB", "keywords": "Antarctica; Bathymetry/Topography; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ground Penetrating Radar; Roosevelt Island; Solid Earth", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Bedrock and Surface Elevations", "url": "https://www.usap-dc.org/view/dataset/609140"}], "date_created": "Fri, 23 May 2003 00:00:00 GMT", "description": "This award is for two years of support to perform radar investigations across former shear margins at Roosevelt Island and Ice Stream C in order to measure changes in the configuration and continuity of internal layers and the bed. The broad goal of these investigations is to gain an understanding of ice stream flow and the timing and mechanisms of ice stream shutdown. A high-resolution short-pulse radar system will be used for detailed examination of the uppermost hundred meters of the firn and ice, and a monopulse sounding-radar system will be used to image the rest of the ice column (including internal layers) and the bed. Changes in the shape and continuity of layers will be used to interpret mechanisms and modes of ice stream flow including the possible migration of stagnation fronts and rates of shut-down. Variations in bed reflectivity will be used to deduce basal hydrology conditions across lineations. Accumulation rates deduced from snow pits and shallow cores will be used to estimate near-surface depth-age profiles. Improved understanding of ice stream history opens the possibility of linking changes in the West Antarctic ice sheet with the geologic evidence from Northern Victoria Land and the ocean record of the retreat of the grounding line in the Ross Sea.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e RA; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Antarctica; Radar Altimetry; NASA; Densification; Bedrock Elevation; Radar Echo Sounders; Ice Sheet Elevation; Satellite Radar Data; GROUND-BASED OBSERVATIONS; radioactive decay; NSIDC; Radar; Ice Core; Snow Stratigraphy; Terrain Elevation; Antarctic Ice Sheet; Stable Isotopes; Ice Surface Elevation; Surface Elevation; Glaciology; Snow Densification; DEMs Antarctica-project; Ice Core Data; GROUND STATIONS; Not provided; DEMs-project; Altimetry; Antarctic; Ice Core Stratigraphy; Ice Stratigraphy", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Radar Investigations of Former Shear Margins: Roosevelt Island and Ice Stream C", "uid": "p0000164", "west": null}, {"awards": "9526420 Taylor, Kendrick", "bounds_geometry": null, "dataset_titles": "Siple Dome Cores Electrical Measurement Data", "datasets": [{"dataset_uid": "609133", "doi": "10.7265/N5DR2SDN", "keywords": "Antarctica; Cryosphere; Electrical Conductivity; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Taylor, Kendrick C.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Cores Electrical Measurement Data", "url": "https://www.usap-dc.org/view/dataset/609133"}], "date_created": "Thu, 08 May 2003 00:00:00 GMT", "description": "This award is for support for the measurement of electrical and optical properties of the Siple Dome ice core. The electrical methods can be used to determine the concentration of the hydrogen ions and the concentration of a weighted sum of all ions. The electrical measurements can resolve features as small as 1 cm. The albedo of the core is also measured with a laser system that can resolve features as small as 0.5 cm. The high spatial resolution of these methods makes them ideal for resolving narrow features in the core, which can be missed in larger composite samples. The measurements will be particularly useful for assisting to date the core and to identify short duration features in the record, such as volcanic eruptions. These measurements will also provide useful information for assessing the temporal variability of Holocene accumulation rate and atmospheric circulation.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "isotopes; NSIDC; Densification; Siple Dome; Glaciology; Snow; WAISCORES; Electrical; GROUND STATIONS; GROUND-BASED OBSERVATIONS; Not provided; Ice Sheet; Siple Coast; Ice Core; thermometry; Siple; measurements; Antarctica", "locations": "Antarctica; Siple Coast; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Taylor, Kendrick C.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Electrical and Optical Measurements on the Siple Dome Ice Core", "uid": "p0000163", "west": null}, {"awards": "9526572 Bales, Roger", "bounds_geometry": null, "dataset_titles": "Snow-atmosphere Transfer Function for Reversibly Deposited Chemical Species in West Antarctica", "datasets": [{"dataset_uid": "609122", "doi": "10.7265/N5ZP441W", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Siple Dome; Snow/Ice; WAISCORES", "people": "McConnell, Joseph; Bales, Roger", "repository": "USAP-DC", "science_program": null, "title": "Snow-atmosphere Transfer Function for Reversibly Deposited Chemical Species in West Antarctica", "url": "https://www.usap-dc.org/view/dataset/609122"}], "date_created": "Thu, 11 Jul 2002 00:00:00 GMT", "description": "This award is for support for a program of measurements to improve our understanding of the relationship between formaldehyde (HCHO) and hydrogen peroxide (H2O2) in the atmosphere and the concentrations of the same species in Antarctic snow, firn and ice. This work aims to relate changes in concentrations in the snow, firn and ice to corresponding changes in tropospheric chemistry. Atmospheric and firn sampling for formaldehyde and hydrogen peroxide at one or more of the WAIS ice core drilling sites will be undertaken and controlled laboratory studies to estimate thermodynamic and rate parameters will be performed. In addition, this work will involve modeling of atmosphere-snow exchange processes to infer the \"transfer function\" for reactive species at the sites and atmospheric photochemical modeling to relate changes in concentrations of formaldehyde and hydrogen peroxide in snow, firn and ice to atmospheric oxidation capacity. This work will contribute to a better understanding of the relationship between atmospheric concentrations of various species and those same species measured in snow and ice samples.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Siple Dome; Antarctica; WAISCORES; thermometry; GROUND-BASED OBSERVATIONS; GROUND STATIONS; Snow; Glaciology; LABORATORY; Siple; Siple Coast; isotopes; Hydrogen Peroxide; Ice Sheet", "locations": "Antarctica; Siple Coast; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bales, Roger; McConnell, Joseph", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Snow-Atmosphere Transfer Function for Reversibly Deposited Chemical Species in West Antarctica", "uid": "p0000060", "west": null}, {"awards": "9526449 Mayewski, Paul", "bounds_geometry": null, "dataset_titles": "WAISCORES Snow Pit Chemistry, Antarctica", "datasets": [{"dataset_uid": "609420", "doi": "10.7265/N5SQ8XBR", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Snow/Ice; Snow Pit; WAIS; WAISCORES", "people": "Kreutz, Karl; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": null, "title": "WAISCORES Snow Pit Chemistry, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609420"}], "date_created": "Thu, 11 Jul 2002 00:00:00 GMT", "description": "This award is for support for a program of glaciochemical analyses of shallow and deep ice cores from Siple Dome, West Antarctica. Measurements that have been proposed include chloride, nitrate, sulfate, calcium, magnesium, sodium, potassium, ammonium and methansulfonic acid. These measurements will provide information about past volcanic events, biomass source strength, sea ice fluctuations, atmospheric circulation, changes in ice-free areas and the environmental response to Earth orbit insolation changes and solar variability. The glaciochemical records from the Siple Dome core will be developed at a resolution sufficient to compare with the Summit, Greenland record, thus allowing a bipolar comparison of climate change event timing and magnitude. As part of this award, an international workshop will be held during the first year to formulate a science plan for the International Transantarctic Scientific Expedition (ITASE), a program of regional surveys documenting the spatial distribution of properties measured in ice cores .", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Ion Chemistry; Antarctic; Snow Chemistry; Stable Isotopes; Snow Density; AGDC; Siple Dome; GROUND-BASED OBSERVATIONS", "locations": "Antarctic; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Kreutz, Karl; Mayewski, Paul A.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Siple Dome Deep Ice Core Glaciochemistry and Regional Survey - A Contribution to the WAIS Initiative", "uid": "p0000012", "west": null}, {"awards": "9615292 Wahlen, Martin", "bounds_geometry": null, "dataset_titles": "Carbon-Isotopic Composition of Atmospheric CO2 since the Last Glacial Maximum; Taylor Dome Ice Core Chemistry, Ion, and Isotope Data", "datasets": [{"dataset_uid": "609246", "doi": "", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "people": "Mayewski, Paul A.; Sowers, Todd A.; Smith, Jesse; Steig, Eric J.; Brook, Edward J.; Indermuhle, A.", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Taylor Dome Ice Core Chemistry, Ion, and Isotope Data", "url": "https://www.usap-dc.org/view/dataset/609246"}, {"dataset_uid": "609108", "doi": "10.7265/N54F1NN5", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "people": "Wahlen, Martin", "repository": "USAP-DC", "science_program": null, "title": "Carbon-Isotopic Composition of Atmospheric CO2 since the Last Glacial Maximum", "url": "https://www.usap-dc.org/view/dataset/609108"}], "date_created": "Tue, 01 Jan 2002 00:00:00 GMT", "description": "This award is for support of a program to reconstruct the record of atmospheric carbon dioxide (and the carbon-13 isotopes of carbon dioxide) over several intervals, including the Last Glacial Maximum-Holocene transition, interstadial episodes, the mid-Holocene, the last 1000 years and the penultimate glacial period, using ice from the Taylor Dome and Vostok ice cores. The major objective of this study is to investigate the phase relationship between variations of the greenhouse gases occluded in the ice cores and temperature changes (indicated by oxygen and deuterium isotopes) during the last deglaciation. In addition, the concentration of atmospheric carbon dioxide over the past 1000 years and during the mid-Holocene will be determined in these cores.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "USAP-DC; Ice Core; isotopes; GROUND-BASED OBSERVATIONS; Carbon; Trapped Gases; Glaciology; GROUND STATIONS; Taylor Dome; Carbon Dioxide; Antarctica; Nitrogen", "locations": "Antarctica; Taylor Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.; Wahlen, Martin; Smith, Jesse; Brook, Edward J.; Indermuhle, A.; Mayewski, Paul A.; Sowers, Todd A.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": null, "title": "Carbon Dioxide and Carbon Isotopes in the Taylor Dome and Vostok Ice Cores", "uid": "p0000153", "west": null}, {"awards": "9222121 Dalziel, Ian", "bounds_geometry": null, "dataset_titles": "Concentration and Isotopic Composition of O2 and N2 in Trapped Gases of the Vostok Ice Core", "datasets": [{"dataset_uid": "609107", "doi": "10.7265/N5862DCW", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciology; Ice Core Records; Lake Vostok; Paleoclimate; UPLC-Q-TOF; Vostok Ice Core", "people": "Bender, Michael", "repository": "USAP-DC", "science_program": null, "title": "Concentration and Isotopic Composition of O2 and N2 in Trapped Gases of the Vostok Ice Core", "url": "https://www.usap-dc.org/view/dataset/609107"}], "date_created": "Tue, 01 Jan 2002 00:00:00 GMT", "description": "This award supports an in situ and short traverse seismic reflection/refraction and magnetotelluric experiment in West Antarctica. This collaborative experiment involves four awards at four institutions. The four-fold purpose is 1) to investigate part of the Byrd Subglacial Basin, 2) to test techniques for this work that could be done in a long traverse, 3) to determine the viability of the magnetotelluric method on a thick (electrically resistive) ice sheet, and 4) to evaluate the relative merits of refraction with wide reflection versus reflection with narrow refraction seismic studies in imaging the lithosphere. The geophysical techniques that will be employed are capable of imaging the ice sheet, the continental lithosphere, and the upper mantle, as well as determining physical properties of parts of the lithosphere and mantle. Investigations of outcrop geology over the last thirty years in West Antarctica and the Transantarctic Mountains have lead to recent interpretations that the crust is made up of many different lithospheric blocks. Seismic reflection work is the only way to image the crust in detail and the refraction work is the only way to determine physical properties of the layers and blocks defined by the reflection work. The magnetotelluric work is scientifically risky because it may not yield useful information when used over the electrically resistive ice sheet; however, if it works it has the potential to image molten rock in the crust and upper mantle. In a continental rift region such as West Antarctica, the presence of melt in the lithosphere is likely and, if documented, has very important ramifications to ice sheet dynamics. Research work supported by this award is expected to provide constraints to models of a range of crustal processes from models of ice sheet dynamics to tectonic and kinematic models of lithospheric thinning and rifting.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "isotopes; Vostok; USAP-DC; Antarctica; Trapped Gases; Ice Core; Glaciology; Nitrogen; GROUND STATIONS", "locations": "Antarctica; Vostok", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Bender, Michael; Dalziel, Ian W.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Seismic Traverse of the Byrd Subglacial Basin-Field Test", "uid": "p0000150", "west": null}, {"awards": "9980538 Lohmann, Kyger", "bounds_geometry": "POINT(-56 -64)", "dataset_titles": "Stable isotope and minor element proxies for Eocene climate of Seymour Island, Antarctica", "datasets": [{"dataset_uid": "600019", "doi": "", "keywords": null, "people": "Lohmann, Kyger", "repository": "USAP-DC", "science_program": null, "title": "Stable isotope and minor element proxies for Eocene climate of Seymour Island, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600019"}], "date_created": "Mon, 11 Jun 2001 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research for construction of a long-term record of climate during the late Cretaceous and early Paleogene to assess the annual seasonality in temperature on the coastal margin of Antarctica. Stable isotope and element compositions of well-preserved bivalve shells collected on Seymour Island will be the primary source of data used to reconstruct paleoenvironmental conditions. Seasonal temperature records collected through high-resolution sampling along growth structures in bivalve shells will allow seasonality to be assessed during different climate states and during periods of rapid climate change. In addition, high stratigraphic resolution will enable this project to detect the presence and frequency of short-lived thermal excursions that may have extended to such high latitudes.\u003cbr/\u003e\u003cbr/\u003eTo compile a reliable temporal record of paleoclimate, two major avenues of investigation will be undertaken: 1) precise stratigraphic (and therefore, temporal) placement of fossils over a large geographic area will be employed through the use of a graphical technique employing geometric projections; 2) stable isotope and elemental analyses will be performed to derive paleotemperatures and to evaluate diagenetic alteration of shell materials. To provide realistic comparisons of paleotemperatures across stratigraphic horizons, this study will focus on a single taxon, thus avoiding complications due to the mixing of faunal assemblages that have been encountered in previous studies of this region.\u003cbr/\u003e\u003cbr/\u003eThe near-shore marine fossil record on Seymour Island provides a unique opportunity to address many questions about the Antarctic paleoenvironment, including the relation between seasonality and different climate states, the influence of climate on biogeographic distribution of specific taxa, the effect of ice-volume changes on the stable isotope record from the late Cretaceous through the Eocene, and the plausibility of high-latitude bottom water formation during this time interval. In particular, information that will be collected concerning patterns of seasonality and the presence (or absence) of short-lived thermal excursions will be extremely valuable to an understanding of the response of high latitude sites during climate transitions from globally cool to globally warm conditions.", "east": -56.0, "geometry": "POINT(-56 -64)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided; Bivalve Shells; GEOCHEMICAL COMPOSITION; Carbon Isotopes; Climate", "locations": null, "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e PALEOGENE \u003e EOCENE", "persons": "Lohmann, Kyger; Barrera, Enriqueta", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.0, "title": "Evolution of Sea Surface Temperatures in the Coastal Antarctic Paleoenvironment During the Late Cretaceous and Paleogene", "uid": "p0000613", "west": -56.0}, {"awards": "9725305 Severinghaus, Jeffrey", "bounds_geometry": null, "dataset_titles": "Firn Air Isotope and Temperature Measurements from Siple Dome and South Pole", "datasets": [{"dataset_uid": "609098", "doi": "10.7265/N51N7Z2P", "keywords": "Antarctica; Atmosphere; Chemistry:Ice; Cryosphere; Geochemistry; Glaciology; Isotope; Paleoclimate; Siple Dome; Snow/Ice; South Pole; Temperature", "people": "Severinghaus, Jeffrey P.; Battle, Mark; Grachev, Alexi", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Firn Air Isotope and Temperature Measurements from Siple Dome and South Pole", "url": "https://www.usap-dc.org/view/dataset/609098"}], "date_created": "Mon, 01 Jan 2001 00:00:00 GMT", "description": "9725305 Severinghaus This award supports a project to develop and apply a new technique for quantifying temperature changes in the past based on the thermodynamic principle of thermal diffusion, in which gas mixtures in a temperature gradient become fractionated. Air in polar firn is fractionated by temperature gradients induced by abrupt climate change, and a record of this air is preserved in bubbles in the ice. The magnitude of the abrupt temperature change, the precise relative timing, and an estimate of the absolute temperature change can be determined. By providing a gas-phase stratigraphic marker of temperature change, the phasing of methane (with decadal precision) and hence widespread climate change (relative to local polar temperature changes) can be determined (across five abrupt warming events during the last glacial period).", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS", "is_usap_dc": true, "keywords": "Isotopic History; GROUND STATIONS; Thermal Diffusion; Firn Temperature Measurements; Not provided; Oxygen Isotopes; Trapped Air Bubbles; Shallow Firn Air; Firn Air Isotope Measurements; Seasonal Temperature Gradients; Mass Spectrometry; GROUND-BASED OBSERVATIONS; Thermal Fractionation; Polar Firn Air; Isotopic Anomalies; Xenon; mass spectrometers; Atmospheric Gases; Argon Isotopes; Siple Dome; Krypton; Nitrogen Isotopes; Seasonal Temperature Changes; Boreholes; Antarctica; Ice Core Gas Records; Firn Air Isotopes; South Pole; Firn Isotopes", "locations": "Antarctica; Siple Dome; South Pole", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Battle, Mark; Grachev, Alexi; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Thermal Fractionation of Firn Air and the Ice Core Record of Abrupt Interstadial Climate Change", "uid": "p0000160", "west": null}, {"awards": "9526374 Alley, Richard", "bounds_geometry": null, "dataset_titles": "Visible Stratigraphic Dating, Siple Dome and Upstream C Cores", "datasets": [{"dataset_uid": "609121", "doi": "10.7265/N53F4MHS", "keywords": "Antarctica; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Sample/Collection Description; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Alley, Richard", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Visible Stratigraphic Dating, Siple Dome and Upstream C Cores", "url": "https://www.usap-dc.org/view/dataset/609121"}], "date_created": "Wed, 01 Jan 1997 00:00:00 GMT", "description": "This award is for support for a program of physical and visible studies on the shallow and deep ice cores to be retrieved from Siple Dome, West Antarctica. Visible examination of ice cores has proven to be a powerful technique for dating and paleoclimatic interpretation. Recent examination of a shallow core from Siple Dome indicates that annual-layer dating is possible and that visible examination will contribute significantly to the dating effort at Siple Dome. Once ages are obtained, distances between layers provide snow accumulation after correction for density variations and ice flow thinning. Thin- section examination of the core will contribute to understanding the visible stratigraphy, and will reveal c-axis fabrics which are related to past ice deformation. The results of this study should include a better understanding of rapid climate change in the Antarctic and should contribute to knowledge of the stability of the West Antarctic ice sheet.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "isotopes; Ice Core; GROUND-BASED OBSERVATIONS; Siple; Ice Sheet; Stratigraphy; GROUND STATIONS; Accumulation; Siple Dome; WAISCORES; Densification; Antarctica; Siple Coast; thermometry; Snow; Not provided; NSIDC; Bubble; Glaciology", "locations": "Antarctica; Siple Coast; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Alley, Richard", "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 Properties of the Siple Dome Deep Ice Core", "uid": "p0000059", "west": null}]

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