USAP-DC

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

[{"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": "1744771 Balco, Gregory", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "5 million year transient Antarctic ice sheet model run with \"desensitized\" marine ice margin instabilities; 5 million year transient Antarctic ice sheet model run with \"sensitized\" marine ice margin instabilities", "datasets": [{"dataset_uid": "601601", "doi": "10.15784/601601", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Sheet Modeling; Marine Ice Margin Instability; Model Output", "people": "Buchband, Hannah; Balco, Gregory; Halberstadt, Anna Ruth", "repository": "USAP-DC", "science_program": null, "title": "5 million year transient Antarctic ice sheet model run with \"desensitized\" marine ice margin instabilities", "url": "https://www.usap-dc.org/view/dataset/601601"}, {"dataset_uid": "601602", "doi": "10.15784/601602", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Sheet Modeling; Marine Ice Margin Instability; Model Output", "people": "Balco, Gregory; Halberstadt, Anna Ruth; Buchband, Hannah", "repository": "USAP-DC", "science_program": null, "title": "5 million year transient Antarctic ice sheet model run with \"sensitized\" marine ice margin instabilities", "url": "https://www.usap-dc.org/view/dataset/601602"}], "date_created": "Tue, 21 Jun 2022 00:00:00 GMT", "description": "The purpose of this project is to use geological data that record past changes in the Antarctic ice sheets to test computer models for ice sheet change. The geologic data mainly consist of dated glacial deposits that are preserved above the level of the present ice sheet, and range in age from thousands to millions of years old. These provide information about the size, thickness, and rate of change of the ice sheets during past times when the ice sheets were larger than present. In addition, some of these data are from below the present ice surface and therefore also provide some information about past warm periods when ice sheets were most likely smaller than present. The primary purpose of the computer model is to predict future ice sheet changes, but because significant changes in the size of ice sheets are slow and likely occur over hundreds of years or longer, the only way to determine whether these models are accurate is to test their ability to reproduce past ice sheet changes. The primary purpose of this project is to carry out such a test. The research team will compile relevant geologic data, in some cases generate new data by dating additional deposits, and develop methods and software to compare data to model simulations. In addition, this project will (i) contribute to building and sustaining U.S. science capacity through postdoctoral training in geochronology, ice sheet modeling, and data science, and (ii) improve public access to geologic data and model simulations relevant to ice sheet change through online database and website development. \u003cbr/\u003e\u003cbr/\u003eTechnical aspects of this project are primarily focused on the field of cosmogenic-nuclide exposure-dating, which is a method that relies on the production of rare stable and radio-nuclides by cosmic-ray interactions with rocks and minerals exposed at the Earth\u0027s surface. Because the advance and retreat of ice sheets results in alternating cosmic-ray exposure and shielding of underlying bedrock and surficial deposits, this technique is commonly used to date and reconstruct past ice sheet changes. First, this project will contribute to compiling and systematizing a large amount of cosmogenic-nuclide exposure age data collected in Antarctica during the past three decades. Second, it will generate additional geochemical data needed to improve the extent and usefulness of measurements of stable cosmogenic nuclides, cosmogenic neon-21 in particular, that are useful for constraining ice-sheet behavior on million-year timescales. Third, it will develop a computational framework for comparison of the geologic data set with existing numerical model simulations of Antarctic ice sheet change during the past several million years, with particular emphasis on model simulations of past warm periods, for example the middle Pliocene ca. 3-3.3 million years ago, during which the Antarctic ice sheets are hypothesized to have been substantially smaller than present. Fourth, guided by the results of this comparison, it will generate new model simulations aimed at improving agreement between model simulations and geologic data, as well as diagnosing which processes or parameterizations in the models are or are not well constrained by the data.\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": "BERYLLIUM-10 ANALYSIS; AMD/US; AMD; ICE SHEETS; GLACIATION; LABORATORY; USA/NSF; Antarctica; ALUMINUM-26 ANALYSIS; USAP-DC", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": null, "persons": "Balco, Gregory", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Synoptic Evaluation of Long-Term Antarctic Ice Sheet Model Simulations using a Continent-Wide Database of Cosmogenic-Nuclide Measurements", "uid": "p0010342", "west": -180.0}, {"awards": "2139497 Balco, Gregory", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 21 Jun 2022 00:00:00 GMT", "description": "This project will conduct basic research into geological dating techniques that are useful for determining the age of glacial deposits in polar regions, Antarctica in particular. These techniques are necessary for determining how large the polar ice sheets were in the geologic past, including during past periods of warm climate that likely resemble present and near-future conditions. Thus, they represent an important technical capability needed for estimating the response of polar ice sheets to climate warming. Because changes in the size of polar ice sheets are the largest potential contribution to future global sea-level change, this capability is also relevant to understanding likely sea-level impacts of future climate change. The research in this project comprises several observational and experimental approaches to improving the speed, efficiency, cost, and accuracy of these techniques, as well as a scientific outreach program aimed at making the resulting capabilities more broadly available to other researchers. The project supports a postdoctoral scholar and contributes to human resources development in polar and climate science.\r\n\r\nThe project focuses on several areas of cosmogenic-nuclide geochemistry, which is a geochemical dating method that relies on the production and decay of cosmic-ray-produced radionuclides in surface rocks. Measurements of these nuclides can be used to quantify the duration of surface exposure and ice cover at locations in Antarctica that are covered and uncovered by changes in the size of the Antarctic ice sheets, thus providing a means of reconstructing past ice-sheet change. The first proposed set of experiments are aimed at implementing a \u0027\u0027virtual mineral separation\u0027\u0027 approach to cosmogenic noble gas analysis that may allow measurement of nuclide concentrations in certain minerals without physically separating the minerals from the host rock. If feasible, this would realize significant speed and cost improvements for this type of analysis. A second set of experiments will focus on means of identifying and quantifying non-cosmogenic background inventories of some relevant nuclides, which is intended to improve the measurement sensitivity and precision for cosmic-ray-produced inventories of these nuclides. A third focus area aims to improve capabilities to measure multiple cosmic-ray-produced nuclides in the same sample, which has the potential to improve the accuracy of dating methods based on these nuclides and to expand the situations in which these methods can be applied. If successful, these experiments are likely to improve a number of applications of cosmogenic-nuclide geochemistry relevant to Antarctic research, including subglacial bedrock exposure dating, dating of multimillion-year-old glacial deposits, and surface-process studies useful in understanding landform evolution and ecosystem dynamics.\r\n\r\nThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "California; LABORATORY; AMD/US; AMD; GEOCHEMISTRY; USAP-DC; USA/NSF", "locations": "California", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Balco, Gregory", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -90.0, "title": "Targeted Basic Research to Enable Antarctic Science Applications of Cosmogenic-Nuclide Geochemistry", "uid": "p0010343", "west": -180.0}, {"awards": "1643664 Severinghaus, Jeffrey; 1643669 Petrenko, Vasilii; 1643716 Buizert, Christo", "bounds_geometry": "POLYGON((112 -66,112.2 -66,112.4 -66,112.6 -66,112.8 -66,113 -66,113.2 -66,113.4 -66,113.6 -66,113.8 -66,114 -66,114 -66.1,114 -66.2,114 -66.3,114 -66.4,114 -66.5,114 -66.6,114 -66.7,114 -66.8,114 -66.9,114 -67,113.8 -67,113.6 -67,113.4 -67,113.2 -67,113 -67,112.8 -67,112.6 -67,112.4 -67,112.2 -67,112 -67,112 -66.9,112 -66.8,112 -66.7,112 -66.6,112 -66.5,112 -66.4,112 -66.3,112 -66.2,112 -66.1,112 -66))", "dataset_titles": "Concentration and isotopic composition of atmospheric N2O over the last century; Law Dome DE08-OH firn air 15N, O2/N2, Ar/N2, 18O of O2; Law Dome DE08-OH site noble gases in ice: testing the 86Krexcess proxy", "datasets": [{"dataset_uid": "601693", "doi": "10.15784/601693", "keywords": "Antarctic; Antarctica; Anthropogenic Emission; Atmosphere; Cryosphere; Cryosphere; Greenhouse Gas; Greenland; Ice Core Data; Nitrification and Denitrification Processes; Nitrous Oxide; Site-specific 15N isotopomer; Styx Glacier", "people": "Ghosh, Sambit; Toyoda, Sakae ; Buizert, Christo ; Langenfelds, Ray L ; Yoshida, Naohiro ; Joong Kim, Seong; Ahn, Jinho ; Etheridge, David", "repository": "USAP-DC", "science_program": null, "title": "Concentration and isotopic composition of atmospheric N2O over the last century", "url": "https://www.usap-dc.org/view/dataset/601693"}, {"dataset_uid": "601598", "doi": "10.15784/601598", "keywords": "Antarctica; Cryosphere; Firn; firn densification; Gravitational Settling; Inert Gases; Law Dome", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Law Dome DE08-OH firn air 15N, O2/N2, Ar/N2, 18O of O2", "url": "https://www.usap-dc.org/view/dataset/601598"}, {"dataset_uid": "601597", "doi": "10.15784/601597", "keywords": "Antarctica; Cryosphere; ice cores; Law Dome; noble gases", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Law Dome DE08-OH site noble gases in ice: testing the 86Krexcess proxy", "url": "https://www.usap-dc.org/view/dataset/601597"}], "date_created": "Fri, 17 Jun 2022 00:00:00 GMT", "description": "Hydroxyl radicals are responsible for removal of most atmospheric trace gases, including pollutants and important greenhouse gases. They have been called the \"detergent of the atmosphere\". Changes in hydroxyl radical concentration in response to large changes in reactive trace gas emissions, which may happen in the future, are uncertain. This project aims to provide the first estimates of the variability of atmospheric hydroxyl radicals since about 1880 AD when anthropogenic emissions of reactive trace gases were minimal. This will improve understanding of their stability in response to large changes in emissions. The project will also investigate whether ice cores record past changes in Southern Hemisphere westerly winds. These winds are a key component of the global climate system, and have an important influence on ocean circulation and possibly on atmospheric carbon dioxide concentrations. The project team will include three early career scientists, a postdoctoral researcher, and graduate and undergraduate students, working in collaboration with senior scientists and Australian collaborators. \u003cbr/\u003e \u003cbr/\u003eFirn air and shallow ice to a depth of about 233 m will be sampled at the Law Dome high-accumulation coastal site in East Antarctica. Trapped air will be extracted from the ice cores on site immediately after drilling. Carbon-14 of carbon monoxide (14CO) will be analyzed in firn and ice-core air samples. Corrections will be made for the in situ cosmogenic 14CO component in the ice, allowing for the atmospheric 14CO history to be reconstructed. This 14CO history will be interpreted with the aid of a chemistry-transport model to place the first observational constraints on the variability of Southern Hemisphere hydroxyl radical concentration after about 1880 AD. An additional component of the project will analyze Krypton-86 in the firn-air and ice-core samples. These measurements will explore whether ice-core Krypton-86 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 westerly winds.\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": 114.0, "geometry": "POINT(113 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; TRACE GASES/TRACE SPECIES; Law Dome; USAP-DC; LABORATORY; ICE CORE AIR BUBBLES; AMD/US; USA/NSF", "locations": "Law Dome", "north": -66.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Petrenko, Vasilii; Murray, Lee T; Buizert, Christo; Petrenko, Vasilii; Murray, Lee T", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "Collaborative Research: Reconstructing Carbon-14 of Atmospheric Carbon Monoxide from Law Dome, Antarctica to Constrain Long-Term Hydroxyl Radical Variability", "uid": "p0010341", "west": 112.0}, {"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": "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": "1542976 Balco, Gregory; 1542936 Goehring, Brent", "bounds_geometry": "POLYGON((-145.7 -64.195,-113.988 -64.195,-82.276 -64.195,-50.564 -64.195,-18.852 -64.195,12.86 -64.195,44.572 -64.195,76.284 -64.195,107.996 -64.195,139.708 -64.195,171.42 -64.195,171.42 -66.2096,171.42 -68.2242,171.42 -70.2388,171.42 -72.2534,171.42 -74.268,171.42 -76.2826,171.42 -78.2972,171.42 -80.3118,171.42 -82.3264,171.42 -84.341,139.708 -84.341,107.996 -84.341,76.284 -84.341,44.572 -84.341,12.86 -84.341,-18.852 -84.341,-50.564 -84.341,-82.276 -84.341,-113.988 -84.341,-145.7 -84.341,-145.7 -82.3264,-145.7 -80.3118,-145.7 -78.2972,-145.7 -76.2826,-145.7 -74.268,-145.7 -72.2534,-145.7 -70.2388,-145.7 -68.2242,-145.7 -66.2096,-145.7 -64.195))", "dataset_titles": "Interface for viewing observational data related to exposure ages measurements and calculated geologic ages derived therefrom", "datasets": [{"dataset_uid": "200199", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Interface for viewing observational data related to exposure ages measurements and calculated geologic ages derived therefrom", "url": "https://version2.ice-d.org/antarctica/nsf/"}], "date_created": "Fri, 03 Sep 2021 00:00:00 GMT", "description": "This project focused on geochemical measurements on rock samples from Antarctica that can be used to reconstruct changes in the size and thickness of the Antarctic ice sheets during the past several thousand years. It applied relatively newly developed technology for measurement of cosmic-ray-produced carbon-14 in quartz to gather new and better information on past ice sheet change from rock samples previously collected in past research in Antarctica. Specifically, it aimed to address a lack of information on past ice sheet change from the Weddell Sea embayment, and the primary result of the project is an improved understanding of ice volume change in this sector of Antarctica during the past ca. 15,000 years. This, in turn, is important in understanding the contribution of the Antarctic ice sheets to global sea level change during this time period. ", "east": 171.42, "geometry": "POINT(12.86 -74.268)", "instruments": null, "is_usap_dc": true, "keywords": "Cosmogenic Dating; GLACIER THICKNESS/ICE SHEET THICKNESS; AMD; USAP-DC; GLACIER ELEVATION/ICE SHEET ELEVATION; GLACIERS/ICE SHEETS; Carbon-14; USA/NSF; Weddell Sea Embayment; AMD/US; LABORATORY; FIELD SURVEYS; GLACIATION", "locations": "Weddell Sea Embayment", "north": -64.195, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Goehring, Brent; Balco, Gregory", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "ICE-D", "repositories": "ICE-D", "science_programs": null, "south": -84.341, "title": "COLLABORATIVE RESEARCH: Resolving Ambiguous Exposure-Age Chronologies of Antarctic Deglaciation with Measurements of In-Situ-Produced Cosmogenic Carbon-14", "uid": "p0010254", "west": -145.7}, {"awards": "2122248 Waters, Laura", "bounds_geometry": "POLYGON((-127.143608 -77.1380528,-127.1012394 -77.1380528,-127.0588708 -77.1380528,-127.0165022 -77.1380528,-126.9741336 -77.1380528,-126.931765 -77.1380528,-126.8893964 -77.1380528,-126.8470278 -77.1380528,-126.8046592 -77.1380528,-126.7622906 -77.1380528,-126.719922 -77.1380528,-126.719922 -77.14809141,-126.719922 -77.15813002,-126.719922 -77.16816863,-126.719922 -77.17820724,-126.719922 -77.18824585,-126.719922 -77.19828446,-126.719922 -77.20832307,-126.719922 -77.21836168,-126.719922 -77.22840029,-126.719922 -77.2384389,-126.7622906 -77.2384389,-126.8046592 -77.2384389,-126.8470278 -77.2384389,-126.8893964 -77.2384389,-126.931765 -77.2384389,-126.9741336 -77.2384389,-127.0165022 -77.2384389,-127.0588708 -77.2384389,-127.1012394 -77.2384389,-127.143608 -77.2384389,-127.143608 -77.22840029,-127.143608 -77.21836168,-127.143608 -77.20832307,-127.143608 -77.19828446,-127.143608 -77.18824585,-127.143608 -77.17820724,-127.143608 -77.16816863,-127.143608 -77.15813002,-127.143608 -77.14809141,-127.143608 -77.1380528))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 19 Aug 2021 00:00:00 GMT", "description": "Isotopic and sedimentary datasets reveal that volcanic activity typically increases during interglacial periods. However, the physical mechanisms through which changes in the surface loading affect volcanic magmatic plumbing systems remain unconstrained. Recently generated 40Ar/39Ar eruption ages indicate that 86% of the dated samples from Mt. Waesche, a late Quaternary volcano in Marie Byrd land, correlate with interglacial periods, suggesting this volcano uniquely responds to changes in the West Antarctic Ice Sheet. We propose to combine the petrology of Mount Waesche\u2019s volcanic record, constraints on changing ice loads through time, and geodynamic modelling to: (1) Determine how pre-eruptive storage conditions change during glacial and interglacial periods using whole rock and mineral compositions of volcanic rocks; (2) Conduct geodynamic modeling to elucidate the relationship between lithospheric structure, temporal variations in ice sheet thickness, and subsequent changes in crustal stresses and magmatic transport and, therefore, the mechanism(s) by which deglaciation impacts magmatic plumbing systems; (3) Use the outcomes of objectives (1) and (2) to provide new constraints on the changes in ice sheet thickness through time that could plausibly trigger future volcanic and magmatic activity in West Antarctica. This collaborative approach will provide a novel methodology to determine prior magnitudes and rates of ice load changes within the Marie Byrd Land region of Antarctica. Lastly, estimates of WAIS elevation changes from this study will be compared to ongoing studies at Mount Waesche focused on constraining last interglacial ice sheet draw down using cosmogenic exposure ages obtained from shallow drilling. The scope of work also includes a partnership with Mentoring Kids Works to develop several Polar and Earth Science Educational Modules aimed at improving reading skills in third grade students in New Mexico. The proposed Polar and Earth Science program consists of modules that include readings of books introducing students to Earth and Polar science themes, paired with Earth and Polar Science activities, followed by simple experiments, where students make predictions and collect data. Information required to implement our Polar and Earth Science curriculum will be made available online.", "east": -126.719922, "geometry": "POINT(-126.931765 -77.18824585)", "instruments": null, "is_usap_dc": true, "keywords": "Mt. Waesche; GEOCHEMISTRY; LITHOSPHERIC PLATE MOTION; STRESS; AMD/US; West Antarctica; Executive Committee Range; NOT APPLICABLE; USAP-DC; AMD; MAJOR ELEMENTS; USA/NSF; ROCKS/MINERALS/CRYSTALS", "locations": "West Antarctica; Mt. Waesche; Executive Committee Range", "north": -77.1380528, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Waters, Laura; Naliboff, John; Zimmerer, Matthew", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repositories": null, "science_programs": null, "south": -77.2384389, "title": "Integrating petrologic records and geodynamics: Quantifying the effects of glaciation on crustal stress and eruptive patterns at Mt. Waesche, Executive Committee Range, Antarctica", "uid": "p0010248", "west": -127.143608}, {"awards": "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": "2317097 Venturelli, Ryan; 1738989 Venturelli, Ryan", "bounds_geometry": "POLYGON((-114 -74,-112.2 -74,-110.4 -74,-108.6 -74,-106.8 -74,-105 -74,-103.2 -74,-101.4 -74,-99.6 -74,-97.8 -74,-96 -74,-96 -74.2,-96 -74.4,-96 -74.6,-96 -74.8,-96 -75,-96 -75.2,-96 -75.4,-96 -75.6,-96 -75.8,-96 -76,-97.8 -76,-99.6 -76,-101.4 -76,-103.2 -76,-105 -76,-106.8 -76,-108.6 -76,-110.4 -76,-112.2 -76,-114 -76,-114 -75.8,-114 -75.6,-114 -75.4,-114 -75.2,-114 -75,-114 -74.8,-114 -74.6,-114 -74.4,-114 -74.2,-114 -74))", "dataset_titles": "200 MHz ground-penetrating radar from Winkie Nunatak, West Antarctica; Cosmogenic-Nuclide data at ICE-D; In situ 14C data from a subglacial bedrock core near Pope and Thwaites glaciers; NBP1902 Expedition data; Pine Island Bay Relative Sea-Level Data", "datasets": [{"dataset_uid": "200296", "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": "601677", "doi": "10.15784/601677", "keywords": "Antarctica; Cryosphere; Ice Penetrating Radar; Pine Island Glacier; Subglacial Bedrock", "people": "Braddock, Scott", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "200 MHz ground-penetrating radar from Winkie Nunatak, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/601677"}, {"dataset_uid": "601554", "doi": "10.15784/601554", "keywords": "Antarctica; Cryosphere; Pine Island Bay; Radiocarbon; Raised Beaches", "people": "Braddock, Scott; Hall, Brenda", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Pine Island Bay Relative Sea-Level Data", "url": "https://www.usap-dc.org/view/dataset/601554"}, {"dataset_uid": "200083", "doi": "10.7284/908147", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1902 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1902"}, {"dataset_uid": "601705", "doi": "10.15784/601705", "keywords": "Antarctica; cosmogenic nuclides; Cryosphere; Mount Murphy; Subglacial Bedrock", "people": "Venturelli, Ryan; Balco, Gregory; Goehring, Brent", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "In situ 14C data from a subglacial bedrock core near Pope and Thwaites glaciers", "url": "https://www.usap-dc.org/view/dataset/601705"}], "date_created": "Tue, 16 Mar 2021 00:00:00 GMT", "description": "This project contributes to the joint initiative launched by the U.S. National Science Foundation (NSF) and the U.K. Natural Environment Research Council (NERC) to substantially improve decadal and longer-term projections of ice loss and sea-level rise originating from Thwaites Glacier in West Antarctica. The Thwaites Glacier system dominates the contribution to sea-level rise from Antarctica. Predicting how this system will evolve in coming decades, and thereby its likely contribution to sea level, requires detailed understanding of how it has responded to changes in climate and oceanographic conditions in the past. This project will provide a record of regional sea-level change by establishing chronologies for raised marine beaches as well as the timing and duration of periods of retreat of Thwaites Glacier during the past 10,000 years by sampling and dating bedrock presently covered by Thwaites Glacier via subglacial drilling. Together with climatic and oceanographic conditions from other records, these will provide boundary conditions for past-to-present model simulations as well as those used to predict future glacier changes under a range of climate scenarios. Specifically, the project will test the hypothesis--implied by existing geological evidence from the region--that present rapid retreat of the Thwaites Glacier system is reversible. \r\n\r\nThe team aims to utilize two approaches: 1. To reconstruct relative sea level during the Holocene, it will map and date raised marine and shoreline deposits throughout Pine Island Bay. Chronological constraints on sea-level change will be provided by radiocarbon dating of organic material in landforms and sediments that are genetically related to past sea level, such as shell fragments, bones of marine fauna, and penguin guano. 2. To obtain geological evidence for past episodes of grounding-line retreat, the team will apply cosmogenic-nuclide exposure-dating of subglacial bedrock. Using drill systems recently developed for subglacial bedrock recovery, the team will obtain subglacial bedrock from sites where ice thickness is dynamically linked to grounding-line position in the Thwaites system (specifically in the Hudson Mountains, and near Mount Murphy). Observation of significant cosmogenic-nuclide concentrations--the team will primarily measure Beryllium-10 and in situ Carbon-14--in these samples would provide direct, unambiguous evidence for past episodes of thinning linked to grounding-line retreat as well as constraints on their timing and duration.", "east": -96.0, "geometry": "POINT(-105 -75)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; FIELD INVESTIGATION; GLACIERS/ICE SHEETS; GLACIAL LANDFORMS; LABORATORY; USAP-DC; GLACIATION; Amundsen Sea; AMD/US; USA/NSF", "locations": "Amundsen Sea", "north": -74.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Goehring, Brent; Hall, Brenda; Campbell, Seth; Venturelli, Ryan A; Balco, Gregory", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "ICE-D", "repositories": "ICE-D; R2R; USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -76.0, "title": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System", "uid": "p0010165", "west": -114.0}, {"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": "1443329 Balco, Gregory; 1443321 Bromley, Gordon", "bounds_geometry": "POLYGON((-180 -85.40705,-179.659078 -85.40705,-179.318156 -85.40705,-178.977234 -85.40705,-178.636312 -85.40705,-178.29539 -85.40705,-177.954468 -85.40705,-177.613546 -85.40705,-177.272624 -85.40705,-176.931702 -85.40705,-176.59078 -85.40705,-176.59078 -85.422615,-176.59078 -85.43818,-176.59078 -85.453745,-176.59078 -85.46931,-176.59078 -85.484875,-176.59078 -85.50044,-176.59078 -85.516005,-176.59078 -85.53157,-176.59078 -85.547135,-176.59078 -85.5627,-176.931702 -85.5627,-177.272624 -85.5627,-177.613546 -85.5627,-177.954468 -85.5627,-178.29539 -85.5627,-178.636312 -85.5627,-178.977234 -85.5627,-179.318156 -85.5627,-179.659078 -85.5627,180 -85.5627,179.277561 -85.5627,178.555122 -85.5627,177.832683 -85.5627,177.110244 -85.5627,176.387805 -85.5627,175.665366 -85.5627,174.942927 -85.5627,174.220488 -85.5627,173.498049 -85.5627,172.77561 -85.5627,172.77561 -85.547135,172.77561 -85.53157,172.77561 -85.516005,172.77561 -85.50044,172.77561 -85.484875,172.77561 -85.46931,172.77561 -85.453745,172.77561 -85.43818,172.77561 -85.422615,172.77561 -85.40705,173.498049 -85.40705,174.220488 -85.40705,174.942927 -85.40705,175.665366 -85.40705,176.387805 -85.40705,177.110244 -85.40705,177.832683 -85.40705,178.555122 -85.40705,179.277561 -85.40705,-180 -85.40705))", "dataset_titles": "Interface for viewing observational data related to exposure ages measurements and calculated geologic ages derived therefrom", "datasets": [{"dataset_uid": "200199", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Interface for viewing observational data related to exposure ages measurements and calculated geologic ages derived therefrom", "url": "https://version2.ice-d.org/antarctica/nsf/"}], "date_created": "Sun, 20 Dec 2020 00:00:00 GMT", "description": "This investigation will reconstruct past behavior of the East Antarctic Ice Sheet during periods of warmer-than-present climate, such as the Pliocene, in order to better project the likely response of Earth\u0027s largest ice sheet to anthropogenic warming. Containing the equivalent of ~55 m sea-level rise, the future evolution of the East Antarctic Ice Sheet has clear societal ramifications on a global scale as temperatures continue to rise. Therefore, determining ice-sheet sensitivity to climate on the scale predicted for the next two centuries is a matter of increasing urgency, particularly in light of evidence suggesting the East Antarctic Ice Sheet is more dynamic than previously thought. This research will provide a terrestrial geologic record of long-term ice-sheet behavior from sites immediately adjacent the East Antarctic Ice Sheet in the Transantarctic Mountains, with which the project will help ascertain how the ice sheet responded to past warm periods. The project will focus primarily on the Pliocene warm period, 5 to 3 million years ago, as this represents the closest analogue to 21st Century climate conditions.\u003cbr/\u003e\u003cbr/\u003eThe proposed research will investigate glacial deposits corresponding to the East Antarctic Ice Sheet in the central Transantarctic Mountains in order to expand the geologic record of past ice-sheet behavior. The overarching research objectives are to improve understanding of the East Antarctic Ice Sheet\u0027s configuration during periods of warmer-than-present climate, such as the Pliocene warm period, and to determine whether the ice sheet underwent significant volume changes or remained relatively stable in response to warming. To address these goals, the investigation will map and date glacial deposits preserved at mountain sites immediately adjacent the ice sheet. Specifically, we will: (i) employ multiple cosmogenic nuclides (10Be, 26Al, 21Ne) to establish more fully ice-thickness histories for the upper Shackleton and Beardmore Glaciers, where they exit the ice sheet; (ii) use this record to identify periods during which the East Antarctic Ice Sheet was at least as extensive as today; and (iii) use these data to assess long-term ice-sheet variability in East Antarctica, with particular emphasis on Pliocene warm episodes. This research will require Antarctic fieldwork, glacial-geologic mapping, and cosmogenic surface-exposure dating.", "east": -176.59078, "geometry": "POINT(178.092415 -85.484875)", "instruments": null, "is_usap_dc": true, "keywords": "Transantarctic Mountains; GLACIERS/ICE SHEETS; AMD; GLACIER THICKNESS/ICE SHEET THICKNESS; GLACIER ELEVATION/ICE SHEET ELEVATION; NOT APPLICABLE; AMD/US; Antarctica", "locations": "Antarctica; Transantarctic Mountains", "north": -85.40705, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Balco, Gregory; Bromley, Gorden; BROMLEY, GORDON", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "ICE-D", "repositories": "ICE-D", "science_programs": null, "south": -85.5627, "title": "Collaborative Research: Potential Direct Geologic Constraint of Ice Sheet Thickness in the Central Transantarctic Mountains during the Pliocene Warm Period", "uid": "p0010153", "west": 172.77561}, {"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": "0838256 Todd, Claire; 0838784 Balco, Gregory; 0838783 Conway, Howard", "bounds_geometry": "POLYGON((-66.27517 -83.23921,-65.341961 -83.23921,-64.408752 -83.23921,-63.475543 -83.23921,-62.542334 -83.23921,-61.609125 -83.23921,-60.675916 -83.23921,-59.742707 -83.23921,-58.809498 -83.23921,-57.876289 -83.23921,-56.94308 -83.23921,-56.94308 -83.359865,-56.94308 -83.48052,-56.94308 -83.601175,-56.94308 -83.72183,-56.94308 -83.842485,-56.94308 -83.96314,-56.94308 -84.083795,-56.94308 -84.20445,-56.94308 -84.325105,-56.94308 -84.44576,-57.876289 -84.44576,-58.809498 -84.44576,-59.742707 -84.44576,-60.675916 -84.44576,-61.609125 -84.44576,-62.542334 -84.44576,-63.475543 -84.44576,-64.408752 -84.44576,-65.341961 -84.44576,-66.27517 -84.44576,-66.27517 -84.325105,-66.27517 -84.20445,-66.27517 -84.083795,-66.27517 -83.96314,-66.27517 -83.842485,-66.27517 -83.72183,-66.27517 -83.601175,-66.27517 -83.48052,-66.27517 -83.359865,-66.27517 -83.23921))", "dataset_titles": "Interface to observational data collected in this project and geologic age information derived therefrom. Dynamic content, continuously updated.; Web page linking to documents containing data collected in this project. Static content", "datasets": [{"dataset_uid": "200194", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Interface to observational data collected in this project and geologic age information derived therefrom. Dynamic content, continuously updated.", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200195", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Web page linking to documents containing data collected in this project. Static content", "url": "http://noblegas.berkeley.edu/~balcs/pensacola/"}], "date_created": "Sat, 19 Dec 2020 00:00:00 GMT", "description": "This award supports a project to find and date geologic evidence of past ice-marginal positions in the Pensacola Mountains, which border the Foundation Ice Stream at the head of the Weddell Sea embayment. The project will involve glacial geologic mapping and cosmogenic-nuclide surface exposure dating of glacially transported erratics. An ice-flow model will be used to link our exposure-dating results together in a glaciologically consistent way, and to relate them to regional LGM to Holocene elevation changes. A secondary focus of the project seeks to improve the effectiveness of exposure-dating methods in understanding ice sheet change. Changes in the location of the ice margin, and thus the exposure ages that record these changes, are controlled not only by regional ice sheet mass balance, but also by local effects on snow- and icefields immediately adjacent to the exposure-dating sites. This part of the project will combine glaciological observations near the present ice margin with targeted exposure- age sampling in an effort to better understand the processes controlling the ice margin location, and improve the interpretation of very recent exposure-age data as a record of latest Holocene to present ice sheet changes. The intellectual merit of the project is that it will provide direct geologic evidence of LGM-to-Holocene ice volume change in a region of Antarctica where no such evidence now exists. The broader impacts of the work involve both gathering information needed for accurate understanding of past and present global sea level change. Secondly, this project will help to develop and maintain the human and intellectual resources necessary for continued excellence in polar research and global change education, by linking experienced Antarctic researchers with early career scientists who seek to develop their expertise in both research and education. In addition, it brings together two early career scientists whose careers are focused at opposite ends of the research-education spectrum, thus facilitating better integration of research and education both in the careers of these scientists and in the outcome of this project. This award has field work in Antarctica.", "east": -56.94308, "geometry": "POINT(-61.609125 -83.842485)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; GLACIER THICKNESS/ICE SHEET THICKNESS; NOT APPLICABLE; GLACIER ELEVATION/ICE SHEET ELEVATION; Antarctica", "locations": "Antarctica", "north": -83.23921, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Balco, Gregory; Todd, Claire; Conway, Howard", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "ICE-D", "repositories": "ICE-D; PI website", "science_programs": null, "south": -84.44576, "title": "Collaborative Research: Last Glacial Maximum and Deglaciation Chronology for the Foundation Ice Stream and Southeastern Weddell Sea Embayment", "uid": "p0010151", "west": -66.27517}, {"awards": "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": "1443213 Kaplan, Michael; 1443433 Licht, Kathy", "bounds_geometry": "POLYGON((159 -83.8,159.5 -83.8,160 -83.8,160.5 -83.8,161 -83.8,161.5 -83.8,162 -83.8,162.5 -83.8,163 -83.8,163.5 -83.8,164 -83.8,164 -83.87,164 -83.94,164 -84.01,164 -84.08,164 -84.15,164 -84.22,164 -84.29,164 -84.36,164 -84.43,164 -84.5,163.5 -84.5,163 -84.5,162.5 -84.5,162 -84.5,161.5 -84.5,161 -84.5,160.5 -84.5,160 -84.5,159.5 -84.5,159 -84.5,159 -84.43,159 -84.36,159 -84.29,159 -84.22,159 -84.15,159 -84.08,159 -84.01,159 -83.94,159 -83.87,159 -83.8))", "dataset_titles": "10Be and 26Al cosmogenic nuclide surface exposure data; 3He input data", "datasets": [{"dataset_uid": "601375", "doi": "10.15784/601375", "keywords": "Antarctica; Cosmogenic Dating; Cryosphere; Transantarctic Mountains", "people": "Kaplan, Michael; Winckler, Gisela; Schaefer, Joerg", "repository": "USAP-DC", "science_program": null, "title": "10Be and 26Al cosmogenic nuclide surface exposure data", "url": "https://www.usap-dc.org/view/dataset/601375"}, {"dataset_uid": "601376", "doi": "10.15784/601376", "keywords": "Antarctica; Cryosphere; Transantarctic Mountains", "people": "Winckler, Gisela; Kaplan, Michael; Schaefer, Joerg", "repository": "USAP-DC", "science_program": null, "title": "3He input data", "url": "https://www.usap-dc.org/view/dataset/601376"}], "date_created": "Tue, 29 Sep 2020 00:00:00 GMT", "description": "Sediments deposited by the Antarctic ice sheet are an archive of its history with time and help geologists to determine how the remote interior of the ice sheet has changed over the past several hundred thousand years. This project will focus on the formation and dynamics of moraines (accumulations of dirt and rocks that are incorporated in the glacier surface or have been pushed along by the glacier as it moves) near the blue ice area of Mt. Achernar in the central Transantarctic Mountains in Antarctica.. The study will improve basic understanding of the formation of these moraines. Fieldwork at the site will focus on imaging the internal structure of the moraine to determine the processes by which it, and others like it, form over time. Additional analyses will include measurements of ice flow and collection of rock samples to determine the timing of debris deposition and the changes in the sources of sediments from deep within the Antarctic continent. The project will provide both graduate and undergraduate students training in paleoclimate studies, geology, and numerical modeling approaches. The broader impacts of the proposed work include hands on training in the Earth Sciences for graduate and undergraduate students, collaboration with colleagues in New Zealand and Sweden to provide an international research experience for students from the US, and three educational modules to be delivered by student researchers regarding Antarctica\u0027s role in global environments. The research is societally relevant and multidisciplinary and the topics are ideal for sharing with the public. All research findings will be made publicly available to others via timely publication in high-impact, peer-reviewed journals and all data will be submitted to the National Snow and Ice Data Center, and excess samples will be provided to the U.S. Polar Rock Repository.\u003cbr/\u003e\u003cbr/\u003eDirect observations of ice sheet history from the margins of Antarctica\u0027s polar plateau are essential for testing numerical ice sheet models, and the laterally extensive, blue-ice moraines of the Mt. Achernar Moraine complex in the central Transantarctic Mountains contain a unique and nearly untapped direct, quasi-continuous record of ice sheet change over multiple glacial cycles. The project objectives include improved understanding of processes and rates of blue ice moraine formation, as well as identifying the topographic, glaciological, and climatic controls on their evolution. Data to be collected with fieldwork in Antarctica include: imaging of internal ice structure with ground-penetrating radar, measurement of ice flow velocity and direction with a global positioning system (GPS) array, analysis of debris concentration and composition in glacier ice, state-of-the-art cosmogenic multi-nuclide analyses to determine exposure ages of moraine debris, mapping of trimlines and provenance analysis. Numerical model simulations, constrained by field data, will be used to evaluate the factors influencing changes in glacier flow that potentially impact the accumulation of the moraine debris. All together, the new data and modeling efforts will improve conceptual models of blue ice moraine formation, and thereby make them a more valuable proxy for developing a better understanding of the history of the ice sheet.", "east": 164.0, "geometry": "POINT(161.5 -84.15)", "instruments": null, "is_usap_dc": true, "keywords": "SEDIMENTS; GLACIAL PROCESSES; AMD/US; Mt. Achernar; ABLATION ZONES/ACCUMULATION ZONES; GLACIER ELEVATION/ICE SHEET ELEVATION; Antarctic Ice Sheet; Transantarctic Mountains; GLACIATION; USAP-DC; CONTINENT \u003e ANTARCTICA; ICE MOTION; AMD; LABORATORY", "locations": "Transantarctic Mountains; Antarctic Ice Sheet; CONTINENT \u003e ANTARCTICA; Mt. Achernar", "north": -83.8, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Kaplan, Michael; Schaefer, Joerg; Winckler, Gisela; Licht, Kathy", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.5, "title": "Collaborative Research: Multidisciplinary Analysis of Antarctic Blue Ice Moraine Formation and their Potential as Climate Archives over Multiple Glacial Cycles", "uid": "p0010131", "west": 159.0}, {"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": "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": "1341680 Sletten, Ronald", "bounds_geometry": "POLYGON((160 -77,160.2 -77,160.4 -77,160.6 -77,160.8 -77,161 -77,161.2 -77,161.4 -77,161.6 -77,161.8 -77,162 -77,162 -77.1,162 -77.2,162 -77.3,162 -77.4,162 -77.5,162 -77.6,162 -77.7,162 -77.8,162 -77.9,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,160.8 -78,160.6 -78,160.4 -78,160.2 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))", "dataset_titles": "Chemical and physical characterization of Beacon Valley and Victoria Valley permafrost cores", "datasets": [{"dataset_uid": "601247", "doi": "10.15784/601247", "keywords": "Aluminum-26; Antarctica; Be-10; Cosmogenic; Cryosphere; Dry Valleys; Geochemistry; Permafrost", "people": "Sletten, Ronald S.", "repository": "USAP-DC", "science_program": null, "title": "Chemical and physical characterization of Beacon Valley and Victoria Valley permafrost cores", "url": "https://www.usap-dc.org/view/dataset/601247"}], "date_created": "Thu, 21 Nov 2019 00:00:00 GMT", "description": "Intellectual Merit: This project will yield new information on the long term Antarctic climate and landscape evolution from measurements of cosmogenic nuclides in quartz sand from two unique permafrost cores collected in Beacon Valley, Antarctica. The two cores have already been drilled in ice-cemented, sand-rich permafrost at 5.5 and 30.6 meters depth, and are currently in cold storage at the University of Washington. The cores are believed to record the monotonic accumulation of sand that has been blown into lower Beacon Valley and inflated the surface over time. The rate of accumulation and any hiatus in the accumulation are believed to reflect in part the advance and retreat of the Taylor Glacier. Preliminary measurements of cosmogenically-produced beryllium (10Be) and aluminum (26Al) in quartz sand in the 5.5-meter depth core reveal that it has been accreting at a rate of 2.5 meters/Myr for the past million years. Furthermore, prior to that time, lower Beacon Valley was most likely covered (shielded from the atmosphere thereby having no or very low production of cosmogenic nuclides in quartz) by Taylor Glacier from 1 to 3.5 Myr BP. These preliminary measurements also suggest that the 30.6 meter core may provide a record of over 10 million years. The emphasis is the full characterization of the core and analysis of cosmogenic nuclides (including cosmogenic neon) in the 30.6 meter permafrost core to develop a burial history of the sands and potentially a record the waxing and waning of the Taylor Glacier. This will allow new tests of our current understanding of surface dynamics and climate history in the McMurdo Dry Valleys (MDV) based on the dated stratigraphy of eolian sand that has been accumulating and inflating the surface for millions of years. This is a new process of surface inflation whose extent has not been well documented, and holds the potential to develop a continuous history of surface burial and glacial expansion. This project will provide a new proxy for understanding the climatic history of the Dry Valleys and will test models for the evolution of permafrost in Beacon Valley.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003e\u003cbr/\u003eThe landscape history of the McMurdo Dry Valleys is important because geological deposits there comprise the richest terrestrial record available from Antarctica. By testing the current age model for these deposits, we will improve understanding of Antarctica?s role in global climate change. This project will train one graduate and one undergraduate student in geochemistry, geochronology, and glacial and periglacial geology. They will participate substantively in the research and are expected to develop their own original ideas. Results from this work will be incorporated into undergraduate and graduate teaching curricula, will be published in the peer reviewed literature, and the data will be made public.", "east": 162.0, "geometry": "POINT(161 -77.5)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; NOT APPLICABLE; BOREHOLES; Antarctica", "locations": "Antarctica", "north": -77.0, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Earth Sciences", "paleo_time": null, "persons": "Sletten, Ronald S.; Stone, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Ancient landscape-active Surfaces: Periglacial Hyperinflation in soils of Beacon Valley, Antarctica", "uid": "p0010068", "west": 160.0}, {"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": "1443346 Stone, John; 1443248 Hall, Brenda", "bounds_geometry": "POLYGON((-174 -84.2,-172.4 -84.2,-170.8 -84.2,-169.2 -84.2,-167.6 -84.2,-166 -84.2,-164.4 -84.2,-162.8 -84.2,-161.2 -84.2,-159.6 -84.2,-158 -84.2,-158 -84.36,-158 -84.52,-158 -84.68,-158 -84.84,-158 -85,-158 -85.16,-158 -85.32,-158 -85.48,-158 -85.64,-158 -85.8,-159.6 -85.8,-161.2 -85.8,-162.8 -85.8,-164.4 -85.8,-166 -85.8,-167.6 -85.8,-169.2 -85.8,-170.8 -85.8,-172.4 -85.8,-174 -85.8,-174 -85.64,-174 -85.48,-174 -85.32,-174 -85.16,-174 -85,-174 -84.84,-174 -84.68,-174 -84.52,-174 -84.36,-174 -84.2))", "dataset_titles": "Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast; Ice-D Antarctic Cosmogenic Nuclide database - site DUNCAN; Ice-D Antarctic Cosmogenic Nuclide database - site MAASON; Liv and Amundsen Glacier Radiocarbon Data", "datasets": [{"dataset_uid": "601226", "doi": "10.15784/601226", "keywords": "Antarctica; Be-10; Beryllium-10; Cosmogenic; Cosmogenic Dating; Cosmogenic Radionuclides; Cryosphere; Deglaciation; Glaciers/Ice Sheet; Glaciology; Liv Glacier; Rocks; Ross Ice Sheet; SURFACE EXPOSURE DATES; Transantarctic Mountains", "people": "Stone, John", "repository": "USAP-DC", "science_program": null, "title": "Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast", "url": "https://www.usap-dc.org/view/dataset/601226"}, {"dataset_uid": "200088", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Ice-D Antarctic Cosmogenic Nuclide database - site DUNCAN", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200087", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Ice-D Antarctic Cosmogenic Nuclide database - site MAASON", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "601208", "doi": "10.15784/601208", "keywords": "Antarctica; Carbon; Cryosphere; Glaciology; Holocene; Radiocarbon; Ross Embayment; Ross Sea; Transantarctic Mountains", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Liv and Amundsen Glacier Radiocarbon Data", "url": "https://www.usap-dc.org/view/dataset/601208"}], "date_created": "Thu, 05 Sep 2019 00:00:00 GMT", "description": "The response of the Antarctic Ice Sheet to future climatic changes is recognized as the greatest uncertainty in projections of future sea level. An understanding of past ice fluctuations affords insight into ice-sheet response to climate and sea-level change and thus is critical for improving sea-level predictions. This project will examine deglaciation of the southern Ross Sea over the past few thousand years to document oscillations in Antarctic ice volume during a period of relatively stable climate and sea level. We will help quantify changes in ice volume, improve understanding of the ice dynamics responsible, and examine the implications for future sea-level change. The project will train future scientists through participation of graduate students, as well as undergraduates who will develop research projects in our laboratories.\u003cbr/\u003e\u003cbr/\u003ePrevious research indicates rapid Ross Sea deglaciation as far south as Beardmore Glacier early in the Holocene epoch (which began approximately 11,700 years before present), followed by more gradual recession. However, deglaciation in the later half of the Holocene remains poorly constrained, with no chronological control on grounding-line migration between Beardmore and Scott Glaciers. Thus, we do not know if mid-Holocene recession drove the grounding line rapidly back to its present position at Scott Glacier, or if the ice sheet withdrew gradually in the absence of significant climate forcing or eustatic sea level change. The latter possibility raises concerns for future stability of the Ross Sea grounding line. To address this question, we will map and date glacial deposits on coastal mountains that constrain the thinning history of Liv and Amundsen Glaciers. By extending our chronology down to the level of floating ice at the mouths of these glaciers, we will date their thinning history from glacial maximum to present, as well as migration of the Ross Sea grounding line southwards along the Transantarctic Mountains. High-resolution dating will come from Beryllium-10 surface-exposure ages of erratics collected along elevation transects, as well as Carbon-14 dates of algae within shorelines from former ice-dammed ponds. Sites have been chosen specifically to allow close comparison of these two dating methods, which will afford constraints on Antarctic Beryllium-10 production rates.", "east": -158.0, "geometry": "POINT(-166 -85)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; NOT APPLICABLE; Antarctica; ICE SHEETS; USAP-DC", "locations": "Antarctica", "north": -84.2, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Hall, Brenda; Stone, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "ICE-D; USAP-DC", "science_programs": null, "south": -85.8, "title": "Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment", "uid": "p0010053", "west": -174.0}, {"awards": "1245899 Kowalewski, Douglas", "bounds_geometry": "POLYGON((-180 -70,-174 -70,-168 -70,-162 -70,-156 -70,-150 -70,-144 -70,-138 -70,-132 -70,-126 -70,-120 -70,-120 -71.5,-120 -73,-120 -74.5,-120 -76,-120 -77.5,-120 -79,-120 -80.5,-120 -82,-120 -83.5,-120 -85,-126 -85,-132 -85,-138 -85,-144 -85,-150 -85,-156 -85,-162 -85,-168 -85,-174 -85,180 -85,178 -85,176 -85,174 -85,172 -85,170 -85,168 -85,166 -85,164 -85,162 -85,160 -85,160 -83.5,160 -82,160 -80.5,160 -79,160 -77.5,160 -76,160 -74.5,160 -73,160 -71.5,160 -70,162 -70,164 -70,166 -70,168 -70,170 -70,172 -70,174 -70,176 -70,178 -70,-180 -70))", "dataset_titles": "Region Climate Model Output Plio-Pleistocene", "datasets": [{"dataset_uid": "601080", "doi": "10.15784/601080", "keywords": "Antarctica; Climate Model; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model; McMurdo; Paleoclimate; Ross Sea", "people": "Kowalewski, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Region Climate Model Output Plio-Pleistocene", "url": "https://www.usap-dc.org/view/dataset/601080"}], "date_created": "Tue, 16 Jan 2018 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to complement the ANDRILL marine record with a terrestrial project that will provide chronological control for past fluctuations of the West Antarctic Ice Sheet (WAIS) and alpine glaciers in McMurdo Sound. The project will develop high-resolution maps of drifts deposited from grounded marine-based ice and alpine glaciers on islands and peninsulas in McMurdo Sound. In addition, the PIs will acquire multi-clast/multi-nuclide cosmogenic analyses of these mapped drift sheets and alpine moraines and use regional climate modeling to shed light on the range of possible environmental conditions in the McMurdo region during periods of grounded ice expansion and recession. The PIs will make use of geological records for ice sheet and alpine glacier fluctuations preserved on the flanks of Mount Discovery, Black Island, and Brown Peninsula. Drifts deposited from grounded, marine-based ice will yield spatial constraints for former advances and retreats of the WAIS. Moraines from alpine glaciers, hypothesized to be of interglacial origin, could yield a first-order record of hydrologic change in the region. Synthesizing the field data, the team proposes to improve the resolution of existing regional-scale climate models for the Ross Embayment. The overall approach and anticipated results will provide the first steps towards linking the marine and terrestrial records in this critical sector of Antarctica.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eResults from the proposed work will be integrated with outreach programs at Boston University, Columbia University, and Worcester State University. The team will actively collaborate with the American Museum of Natural History to feature this project prominently in museum outreach. The team will also include a PolarTREC teacher as a member of the research team. The geomorphological results will be presented in 3D at Boston University?s Antarctic Digital Image Analyses Lab. The research will form the basis of a PhD dissertation at Boston University.", "east": -120.0, "geometry": "POINT(-160 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -70.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kowalewski, Douglas", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Collaborative Research: West Antarctic Ice Sheet stability, Alpine Glaciation, and Climate Variability: a Terrestrial Perspective from Cosmogenic-nuclide Dating in McMurdo Sound", "uid": "p0000391", "west": 160.0}, {"awards": "1341420 Balco, Gregory; 1341364 Todd, Claire; 1460449 Goehring, Brent", "bounds_geometry": "POLYGON((164.08 -74.6,164.0842 -74.6,164.0884 -74.6,164.0926 -74.6,164.0968 -74.6,164.101 -74.6,164.1052 -74.6,164.1094 -74.6,164.1136 -74.6,164.1178 -74.6,164.122 -74.6,164.122 -74.6023,164.122 -74.6046,164.122 -74.6069,164.122 -74.6092,164.122 -74.6115,164.122 -74.6138,164.122 -74.6161,164.122 -74.6184,164.122 -74.6207,164.122 -74.623,164.1178 -74.623,164.1136 -74.623,164.1094 -74.623,164.1052 -74.623,164.101 -74.623,164.0968 -74.623,164.0926 -74.623,164.0884 -74.623,164.0842 -74.623,164.08 -74.623,164.08 -74.6207,164.08 -74.6184,164.08 -74.6161,164.08 -74.6138,164.08 -74.6115,164.08 -74.6092,164.08 -74.6069,164.08 -74.6046,164.08 -74.6023,164.08 -74.6))", "dataset_titles": "Interface to observational data associated with exposure-age measurements and resulting calculated ages. Dynamic content, updated.", "datasets": [{"dataset_uid": "200196", "doi": null, "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Interface to observational data associated with exposure-age measurements and resulting calculated ages. Dynamic content, updated.", "url": "https://version2.ice-d.org/antarctica/nsf/"}], "date_created": "Wed, 18 Oct 2017 00:00:00 GMT", "description": "The investigators will map glacial deposits and date variations in glacier variability at several ice-free regions in northern Victoria Land, Antarctica. These data will constrain the nature and timing of past ice thickness changes for major glaciers that drain into the northwestern Ross Sea. This is important because during the Last Glacial Maximum (15,000 - 18,000 years ago) these glaciers were most likely flowing together with grounded ice from both the East and West Antarctic Ice Sheets that expanded across the Ross Sea continental shelf to near the present shelf edge. Thus, the thickness of these glaciers was most likely controlled in part by the extent and thickness of the Ross Sea ice sheet and ice shelf. The data the PIs propose to collect can provide constraints on the position of the grounding line in the western Ross Sea during the Last Glacial Maximum, the time that position was reached, and ice thickness changes that occurred after that time. The primary intellectual merit of this project will be to improve understanding of a period of Antarctic ice sheet history that is relatively unconstrained at present and also potentially important in understanding past ice sheet-sea level interactions. \u003cbr/\u003e\u003cbr/\u003eThis proposal will support an early career researcher\u0027s ongoing program of undergraduate education and research that is building a socio-economically diverse student body with students from backgrounds underrepresented in the geosciences. This proposal will also bring an early career researcher into Antarctic research.", "east": 164.122, "geometry": "POINT(164.101 -74.6115)", "instruments": null, "is_usap_dc": true, "keywords": "AMD/US; AMD; Cosmogenic Dating; LABORATORY; NSF; exposure-age; NOT APPLICABLE; Ross Sea", "locations": "Ross Sea", "north": -74.6, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Goehring, Brent; Balco, Gregory; Todd, Claire", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "ICE-D", "repositories": "ICE-D", "science_programs": null, "south": -74.623, "title": "Collaborative Research: Terrestrial Exposure-Age Constraints on the last Glacial Maximum Extent of the Antarctic Ice Sheet in the Western Ross Sea", "uid": "p0000306", "west": 164.08}, {"awards": "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": "1341284 Swanger, Kate", "bounds_geometry": "POLYGON((161 -77.5,161.2 -77.5,161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.2 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163 -77.525,163 -77.55,163 -77.575,163 -77.6,163 -77.625,163 -77.65,163 -77.675,163 -77.7,163 -77.725,163 -77.75,162.8 -77.75,162.6 -77.75,162.4 -77.75,162.2 -77.75,162 -77.75,161.8 -77.75,161.6 -77.75,161.4 -77.75,161.2 -77.75,161 -77.75,161 -77.725,161 -77.7,161 -77.675,161 -77.65,161 -77.625,161 -77.6,161 -77.575,161 -77.55,161 -77.525,161 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 09 Oct 2017 00:00:00 GMT", "description": "Paragraph for Laypersons:\u003cbr/\u003eThis research focuses on the history of rock glaciers and buried glacial ice in the McMurdo Dry Valleys region of Antarctica. Rock glaciers are flowing mixtures of ice and sediments common throughout alpine and high-latitude regions on Earth and Mars. Despite similar appearances, rock glaciers can form under highly variable environmental and hydrological conditions. The main research questions addressed here are: 1) what environmental and climatological conditions foster long-term preservation of rock glaciers in Antarctica, 2) what role do rock glaciers play in Antarctic landscape evolution and the local water cycle, and 3) what can rock glaciers reveal about the extent and timing of previous glacial advances? The project will involve two Antarctic field seasons to image the interior of Antarctic rock glaciers using ground-penetrating radar, to gather ice cores for chemical analyses, and to gather surface sediments for dating. The Dry Valleys host the world?s southernmost terrestrial ecosystem (soil, stream and lake micro-organisms and mosses); rock glaciers and ground-ice are an important and poorly-studied source of meltwater and nutrients for these ecosystems. This research will shed light on the glacial and hydrological history of the Dry Valleys region and the general environmental conditions the foster rock glaciers, features that generally occur in warmer and/or wetter locations. The research will provide support for five graduate/undergraduate students, who will actively gather data in the field, followed by interpretation, dissemination and presentation of the data. Additionally, the researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities. A series of time-lapse images of hydrological processes, and videos of researchers in the field, will serve as a dramatic centerpiece in community and school presentations.\u003cbr/\u003e\u003cbr/\u003eParagraph for Scientific Community:\u003cbr/\u003eRock glaciers are common in the McMurdo Dry Valleys, but are concentrated in a few isolated regions: western Taylor Valley, western Wright Valley, Pearse Valley and Bull Pass. The investigators hypothesize that the origin and age of these features varies by region: that rock glaciers in Pearse and Taylor valley originated as buried glacier ice, whereas rock glaciers in Wright Valley formed through permafrost processes, such as mobilization of ice-rich talus. To address these hypotheses, the project will: 1) develop relative and absolute chronologies for the rock glaciers through field mapping and optically stimulated luminescence dating of overlying sediments, 2) assess the origin of clean-ice cores through stable isotopic analyses, and 3) determine if present-day soil-moisture and temperature conditions are conducive to rock glacier formation/preservation. The proposed research will provide insight into the spatial and temporal distribution of buried glacier ice and melt-water-derived ground ice in the McMurdo Dry Valleys, with implications for glacial history, as well as the potential role of rock glaciers in the regional hydrologic cycle (and the role of ground-ice as a source for moisture and nutrient for local ecosystems). The project will provide general constraints on the climatic and hydrologic conditions that foster permafrost rock glaciers, features that generally occur under warmer and wetter conditions than those found in the present-day McMurdo Dry Valleys. The application of OSL and cosmogenic exposure\u003cbr/\u003edating is novel to rock glaciers, geomorphic features that have proven difficult to date, despite their ubiquity in Antarctica and their potential scientific importance. The research will provide support for five graduate/undergraduate students, who will participate in the field work, followed by interpretation, dissemination and presentation of the data. The researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities.", "east": 163.0, "geometry": "POINT(162 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Swanger, Kate", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.75, "title": "Origin and Climatic Significance of Rock Glaciers in the McMurdo Dry Valleys: Assessing Spatial and Temporal Variability", "uid": "p0000297", "west": 161.0}, {"awards": "1142002 Kaplan, Michael", "bounds_geometry": "POLYGON((-58 -63.7,-57.95 -63.7,-57.9 -63.7,-57.85 -63.7,-57.8 -63.7,-57.75 -63.7,-57.7 -63.7,-57.65 -63.7,-57.6 -63.7,-57.55 -63.7,-57.5 -63.7,-57.5 -63.73,-57.5 -63.76,-57.5 -63.79,-57.5 -63.82,-57.5 -63.85,-57.5 -63.88,-57.5 -63.91,-57.5 -63.94,-57.5 -63.97,-57.5 -64,-57.55 -64,-57.6 -64,-57.65 -64,-57.7 -64,-57.75 -64,-57.8 -64,-57.85 -64,-57.9 -64,-57.95 -64,-58 -64,-58 -63.97,-58 -63.94,-58 -63.91,-58 -63.88,-58 -63.85,-58 -63.82,-58 -63.79,-58 -63.76,-58 -63.73,-58 -63.7))", "dataset_titles": "10Be and 14C data from northern Antarctic Peninsula", "datasets": [{"dataset_uid": "601051", "doi": "10.15784/601051", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Glaciers/Ice Sheet; GPS; James Ross Island; Sample/Collection Description; Solid Earth", "people": "Kaplan, Michael", "repository": "USAP-DC", "science_program": null, "title": "10Be and 14C data from northern Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601051"}], "date_created": "Tue, 19 Sep 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to investigate last glacial maximum through Holocene glacial change on the northeastern Antarctic Peninsula, an area distinguished by dramatic ice shelf collapses and retreat of upstream glaciers. However, there is a lack of long-term context to know the relative significance of recent events over longer time scales. The PIs will obtain data on former ice margin positions, ice thicknesses, glacier retreat and thinning rates, and Holocene glacier change in the James Ross Island Archipelago and areas near the former Larsen-A ice shelf. These data include maximum- and minimum-limiting 14C and cosmogenic-nuclide exposure dates integrated with geomorphology and stratigraphy. Understanding the extent, nature, and history of glacial events is important for placing current changes in glacial extent into a long-term context. This research will also contribute to understanding the sensitivity of ice shelves and glaciers in this region to climate change. Records of changes in land-terminating glaciers will also address outstanding questions related to climate change since the LGM and through the Holocene. The PIs will collect samples during cooperative field projects with scientists of the Instituto Anta\u0026#769;rtico Argentino and the Korea Polar Research Institute planned as part of existing, larger, research projects.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe proposed work includes collaborations with Argentina and Korea. The PIs are currently involved in or are initiating education and outreach activities that will be incorporated into this project. These include interactions with the American Museum of Natural History, the United States Military Academy at West Point, and undergraduate involvement in their laboratories. This project provides a significant opportunity to engage the public as it focuses on an area where environmental changes are the object of attention in the popular media.", "east": -57.5, "geometry": "POINT(-57.75 -63.85)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; GLACIATION; Not provided", "locations": "Antarctic Peninsula", "north": -63.7, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": null, "persons": "Kaplan, Michael", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.0, "title": "Terrestrial Geological Context for Glacier Change in the Northeast Antarctica Peninsula", "uid": "p0000337", "west": -58.0}, {"awards": "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": "1043517 Clark, Peter; 1043485 Curtice, Josh; 1043018 Pollard, David", "bounds_geometry": "POLYGON((163.5 -77.57,163.685 -77.57,163.87 -77.57,164.055 -77.57,164.24 -77.57,164.425 -77.57,164.61 -77.57,164.795 -77.57,164.98 -77.57,165.165 -77.57,165.35 -77.57,165.35 -77.645,165.35 -77.72,165.35 -77.795,165.35 -77.87,165.35 -77.945,165.35 -78.02,165.35 -78.095,165.35 -78.17,165.35 -78.245,165.35 -78.32,165.165 -78.32,164.98 -78.32,164.795 -78.32,164.61 -78.32,164.425 -78.32,164.24 -78.32,164.055 -78.32,163.87 -78.32,163.685 -78.32,163.5 -78.32,163.5 -78.245,163.5 -78.17,163.5 -78.095,163.5 -78.02,163.5 -77.945,163.5 -77.87,163.5 -77.795,163.5 -77.72,163.5 -77.645,163.5 -77.57))", "dataset_titles": "A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea; Ice Sheet Model Output, West Antarctic Ice Sheet Deglaciation", "datasets": [{"dataset_uid": "600123", "doi": "10.15784/600123", "keywords": "Antarctica; Cosmogenic Dating; Cryosphere; Ross Sea; Sample/Collection Description; Southern Ocean; WAIS", "people": "Curtice, Josh; Kurz, Mark D.", "repository": "USAP-DC", "science_program": null, "title": "A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600123"}, {"dataset_uid": "609639", "doi": "10.7265/N5NC5Z53", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model", "people": "Pollard, David", "repository": "USAP-DC", "science_program": null, "title": "Ice Sheet Model Output, West Antarctic Ice Sheet Deglaciation", "url": "https://www.usap-dc.org/view/dataset/609639"}], "date_created": "Sat, 15 Oct 2016 00:00:00 GMT", "description": "1043517/Clark\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop a better understanding of the response of the WAIS to climate change. The timing of the last deglaciation of the western Ross Sea will be improved using in situ terrestrial cosmogenic nuclides (3He, 10Be, 14C, 26Al, 36Cl) to date glacial erratics at key areas and elevations along the western Ross Sea coast. A state-of-the art ice sheet-shelf model will be used to identify mechanisms of deglaciation of the Ross Sea sector of WAIS. The model results and forcing will be compared with observations including the new cosmogenic data proposed here, with the aim of better determining and understanding the history and causes of WAIS deglaciation in the Ross Sea. There is considerable uncertainty, however, in the history of grounding line retreat from its last glacial maximum position, and virtually nothing is known about the timing of ice- surface lowering prior to ~10,000 years ago. Given these uncertainties, we are currently unable to assess one of the most important questions regarding the last deglaciation of the global ice sheets, namely as to whether the Ross Sea sector of WAIS contributed significantly to meltwater pulse 1A (MWP-1A), an extraordinarily rapid (~500-year duration) episode of ~20 m sea-level rise that occurred ~14,500 years ago. The intellectual merit of this project is that recent observations of startling changes at the margins of the Greenland and Antarctic ice sheets indicate that dynamic responses to warming may play a much greater role in the future mass balance of ice sheets than considered in current numerical projections of sea level rise. The broader impacts of this work are that it has direct societal relevance to developing an improved understanding of the response of the West Antarctic ice sheet to current and possible future environmental changes including the sea-level response to glacier and ice sheet melting due to global warming. The PI will communicate results from this project to a variety of audiences through the publication of peer-reviewed papers and by giving talks to public audiences. Finally the project will support a graduate student and undergraduate students in all phases of field-work, laboratory work and data interpretation.", "east": 165.35, "geometry": "POINT(164.425 -77.945)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e DATA ANALYSIS \u003e ENVIRONMENTAL MODELING \u003e COMPUTER", "is_usap_dc": true, "keywords": "Ocean Depth; Not provided; AGDC-project; Model Output; Sea Level Rise; Surface Accumulation Rate; Surface Melt Rate; Ocean Melt Rate; Total Ice Volume; Modeling; Calving Rate; Total Ice Area; bed elevations; LABORATORY", "locations": null, "north": -77.57, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Pollard, David; Curtice, Josh; Clark, Peter; Kurz, Mark D.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.32, "title": "Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "uid": "p0000194", "west": 163.5}, {"awards": "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": "1142162 Stone, John", "bounds_geometry": "POLYGON((-104.14 -81.07,-102.24 -81.07,-100.34 -81.07,-98.44 -81.07,-96.54 -81.07,-94.64 -81.07,-92.74 -81.07,-90.84 -81.07,-88.94 -81.07,-87.04 -81.07,-85.14 -81.07,-85.14 -81.207,-85.14 -81.344,-85.14 -81.481,-85.14 -81.618,-85.14 -81.755,-85.14 -81.892,-85.14 -82.029,-85.14 -82.166,-85.14 -82.303,-85.14 -82.44,-87.04 -82.44,-88.94 -82.44,-90.84 -82.44,-92.74 -82.44,-94.64 -82.44,-96.54 -82.44,-98.44 -82.44,-100.34 -82.44,-102.24 -82.44,-104.14 -82.44,-104.14 -82.303,-104.14 -82.166,-104.14 -82.029,-104.14 -81.892,-104.14 -81.755,-104.14 -81.618,-104.14 -81.481,-104.14 -81.344,-104.14 -81.207,-104.14 -81.07))", "dataset_titles": "Cosmogenic nuclide data at ICE-D; Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "datasets": [{"dataset_uid": "600162", "doi": "10.15784/600162", "keywords": "Antarctica; Be-10; Chemistry:Rock; Cosmogenic Dating; Cryosphere; Glaciology; Nunataks; Sample/Collection Description; Solid Earth; Whitmore Mountains", "people": "Stone, John", "repository": "USAP-DC", "science_program": null, "title": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "url": "https://www.usap-dc.org/view/dataset/600162"}, {"dataset_uid": "200299", "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/"}], "date_created": "Wed, 16 Mar 2016 00:00:00 GMT", "description": "1142162/Stone\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to conduct a reconnaissance geological and radar-sounding study of promising sites in West Antarctica as a prelude to a future project to conduct subglacial cosmogenic nuclide measurements. Field work will take place in the Whitmore Mountains, close to the WAIS divide, and on the Nash and Pirrit Hills, downflow from the divide in the Weddell Sea drainage. At each site geological indicators of higher (and lower) ice levels in the past will be mapped and evidence of subglacial erosion or its absence will be documented. Elevation transects of both glacial erratics and adjacent bedrock samples will be collected to establish the timing of recent deglaciation at the sites and provide a complement to similar measurements on material from depth transects obtained by future subglacial drilling. At each site, bedrock ridges will be traced into the subsurface with closely-spaced ice-penetrating radar surveys, using a combination of instruments and frequencies to obtain meter-scale surface detail, using synthetic aperture techniques. Collectively the results will define prospective sites for subglacial sampling, and maximize the potential information to be obtained from such samples in future studies. The intellectual merit of this project is that measurements of cosmogenic nuclides in subglacial bedrock hold promise for resolving the questions of whether the West Antarctic ice sheet collapsed completely in the past, whether it is prone to repeated large deglaciations, and if so, what is their magnitude and frequency. Such studies will require careful choice of targets, to locate sites where bedrock geology is favorable, cosmogenic nuclide records are likely to have been protected from subglacial erosion, and the local ice-surface response is indicative of large-scale ice sheet behavior. The broader impacts of this work include helping to determine whether subglacial surfaces in West Antarctica were ever exposed to cosmic rays, which will provide unambiguous evidence for or against a smaller ice sheet in the past. This is an important step towards establishing whether the WAIS is vulnerable to collapse in future, and will ultimately help to address uncertainty in forecasting sea level change. The results will also provide ground truth for models of ice-sheet dynamics and long-term ice sheet evolution, and will help researchers use these models to identify paleoclimate conditions responsible for WAIS deglaciation. The education and training of students (both undergraduate and graduate students) will play an important role in the project, which will involve Antarctic fieldwork, technically challenging labwork, data collection and interpretation, and communication of the outcome to scientists and the general public.", "east": -85.14, "geometry": "POINT(-94.64 -81.755)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; Antarctica; ICE SHEETS", "locations": "Antarctica", "north": -81.07, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Stone, John; Conway, Howard; Winebrenner, Dale", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "ICE-D; USAP-DC", "science_programs": null, "south": -82.44, "title": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "uid": "p0000335", "west": -104.14}, {"awards": "1043724 Swanger, Kate", "bounds_geometry": "POLYGON((160.3 -77.4,160.52 -77.4,160.74 -77.4,160.96 -77.4,161.18 -77.4,161.4 -77.4,161.62 -77.4,161.84 -77.4,162.06 -77.4,162.28 -77.4,162.5 -77.4,162.5 -77.44,162.5 -77.48,162.5 -77.52,162.5 -77.56,162.5 -77.6,162.5 -77.64,162.5 -77.68,162.5 -77.72,162.5 -77.76,162.5 -77.8,162.28 -77.8,162.06 -77.8,161.84 -77.8,161.62 -77.8,161.4 -77.8,161.18 -77.8,160.96 -77.8,160.74 -77.8,160.52 -77.8,160.3 -77.8,160.3 -77.76,160.3 -77.72,160.3 -77.68,160.3 -77.64,160.3 -77.6,160.3 -77.56,160.3 -77.52,160.3 -77.48,160.3 -77.44,160.3 -77.4))", "dataset_titles": null, "datasets": null, "date_created": "Sat, 05 Dec 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to investigate the impact of earth surface processes on the application of cosmogenic exposure dating in Antarctica by combining multi-nuclide techniques, detailed field experiments, rock-mechanic studies, and climate modeling. They will analyze cosmogenic-nuclide inventories for a suite of six alpine-moraine systems in inland regions of the McMurdo Dry Valleys. This area is ideally suited for this study because 1) the targeted alpine moraine sequences are critically important in helping to reconstruct past temperature and precipitation values over the last several million years, 2) the production rates for cosmogenic nuclides are typically high and well-known, and 3) the complexity of surface processes is relatively low. Their work has two specific goals: to evaluate the effects of episodic geomorphic events in modulating cosmogenic inventories in surface rocks in polar deserts and to generate an alpine glacier chronology that will serve as a robust record of regional climate variation over the last several million years. A key objective is to produce a unique sampling strategy that yields consistent exposure-age results by minimizing the effects of episodic geomorphic events that obfuscate cosmogenic-nuclide chronologies. They will link their moraine chronology with regional-scale atmospheric models developed by collaborators at University of Massachusetts Amherst.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis research is interdisciplinary and includes two early career scientists. Results of this work will be used to enhance undergraduate education by engaging two female students in Antarctic field and summer research projects. Extended outreach includes development of virtual Antarctic field trips for Colgate University?s Ho Tung Visualization Laboratory and Boston University?s Antarctic Digital Image Analyses Laboratory. The PIs will continue to work with the Los Angeles Valley Community College, which serves students of mostly Hispanic origin as part of the PolarTREC program. This project will contribute to the collaboration between LDEO and several New York City public high schools within the Lamont-Doherty Secondary School Field Program.", "east": 162.5, "geometry": "POINT(161.4 -77.6)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.4, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Swanger, Kate", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.8, "title": "Collaborative Research: Multi-nuclide approach to systematically evaluate the scatter in surface exposure ages in Antarctica and to develop consistent alpine glacier chronologies", "uid": "p0000406", "west": 160.3}, {"awards": "1043706 Marchant, David", "bounds_geometry": "POLYGON((160 -76.5,160.45 -76.5,160.9 -76.5,161.35 -76.5,161.8 -76.5,162.25 -76.5,162.7 -76.5,163.15 -76.5,163.6 -76.5,164.05 -76.5,164.5 -76.5,164.5 -76.7,164.5 -76.9,164.5 -77.1,164.5 -77.3,164.5 -77.5,164.5 -77.7,164.5 -77.9,164.5 -78.1,164.5 -78.3,164.5 -78.5,164.05 -78.5,163.6 -78.5,163.15 -78.5,162.7 -78.5,162.25 -78.5,161.8 -78.5,161.35 -78.5,160.9 -78.5,160.45 -78.5,160 -78.5,160 -78.3,160 -78.1,160 -77.9,160 -77.7,160 -77.5,160 -77.3,160 -77.1,160 -76.9,160 -76.7,160 -76.5))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 23 Oct 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to investigate the impact of earth surface processes on the application of cosmogenic exposure dating in Antarctica by combining multi-nuclide techniques, detailed field experiments, rock-mechanic studies, and climate modeling. They will analyze cosmogenic-nuclide inventories for a suite of six alpine-moraine systems in inland regions of the McMurdo Dry Valleys. This area is ideally suited for this study because 1) the targeted alpine moraine sequences are critically important in helping to reconstruct past temperature and precipitation values over the last several million years, 2) the production rates for cosmogenic nuclides are typically high and well-known, and 3) the complexity of surface processes is relatively low. Their work has two specific goals: to evaluate the effects of episodic geomorphic events in modulating cosmogenic inventories in surface rocks in polar deserts and to generate an alpine glacier chronology that will serve as a robust record of regional climate variation over the last several million years. A key objective is to produce a unique sampling strategy that yields consistent exposure-age results by minimizing the effects of episodic geomorphic events that obfuscate cosmogenic-nuclide chronologies. They will link their moraine chronology with regional-scale atmospheric models developed by collaborators at University of Massachusetts Amherst.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis research is interdisciplinary and includes two early career scientists. Results of this work will be used to enhance undergraduate education by engaging two female students in Antarctic field and summer research projects. Extended outreach includes development of virtual Antarctic field trips for Colgate University?s Ho Tung Visualization Laboratory and Boston University?s Antarctic Digital Image Analyses Laboratory. The PIs will continue to work with the Los Angeles Valley Community College, which serves students of mostly Hispanic origin as part of the PolarTREC program. This project will contribute to the collaboration between LDEO and several New York City public high schools within the Lamont-Doherty Secondary School Field Program.", "east": 164.5, "geometry": "POINT(162.25 -77.5)", "instruments": null, "is_usap_dc": false, "keywords": "rock weathering; McMurdo Dry Valleys; Not provided", "locations": null, "north": -76.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Marchant, David", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -78.5, "title": "Collaborative Research: Multi-nuclide approach to systematically evaluate the scatter in surface exposure ages in Antarctica and to develop consistent alpine glacier chronologies", "uid": "p0000269", "west": 160.0}, {"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": "0944475 Kaplan, Michael", "bounds_geometry": "POLYGON((-149.7 -84.1,-118.61 -84.1,-87.52 -84.1,-56.43 -84.1,-25.34 -84.1,5.75 -84.1,36.84 -84.1,67.93 -84.1,99.02 -84.1,130.11 -84.1,161.2 -84.1,161.2 -84.43,161.2 -84.76,161.2 -85.09,161.2 -85.42,161.2 -85.75,161.2 -86.08,161.2 -86.41,161.2 -86.74,161.2 -87.07,161.2 -87.4,130.11 -87.4,99.02 -87.4,67.93 -87.4,36.84 -87.4,5.75 -87.4,-25.34 -87.4,-56.43 -87.4,-87.52 -87.4,-118.61 -87.4,-149.7 -87.4,-149.7 -87.07,-149.7 -86.74,-149.7 -86.41,-149.7 -86.08,-149.7 -85.75,-149.7 -85.42,-149.7 -85.09,-149.7 -84.76,-149.7 -84.43,-149.7 -84.1))", "dataset_titles": "Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "datasets": [{"dataset_uid": "600115", "doi": "10.15784/600115", "keywords": "Antarctica; Cosmogenic Dating; Cryosphere; Sample/Collection Description; Solid Earth; Transantarctic Mountains", "people": "Kaplan, Michael", "repository": "USAP-DC", "science_program": null, "title": "Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "url": "https://www.usap-dc.org/view/dataset/600115"}], "date_created": "Thu, 17 Jul 2014 00:00:00 GMT", "description": "The proposed work will investigate changes in the compositional variation of glacial tills over time across two concentric sequences of Pleistocene moraines located adjacent to the heads of East Antarctic outlet glaciers in the Transantarctic Mountains (TAM). The chronologic framework for this work will be generated from cosmogenic exposure ages of boulders on prominent morainal ridges. The PIs hypothesize that variations in till composition may indicate a change in ice flow direction or a change in the composition of the original source area, while ages of the moraines provide a long-term terrestrial perspective on ice sheet dynamics. Both results are vital for modeling experiments that aim to reconstruct the East Antarctic Ice Sheet and assess its role in the global climate system and its potential impact on global sea level rise. The variation of till compositions through time also allows for a more accurate interpretation of sediment cores from the Ross Sea and the Southern Ocean. Additionally, till exposures at the head of some East Antarctic outlet glaciers have been shown to contain subglacial material derived from East Antarctic bedrock, providing a window through the ice to view East Antarctica?s inaccessible bedrock. Till samples will be collected from two well-preserved sequences of moraine crests at Mt. Howe (head of Scott Glacier) and Mt. Achernar (between Beardmore and Nimrod Glaciers). Each size fraction in glacial till provides potentially valuable information, and the PIs will measure the petrography of the clast and sand fractions, quantitative X-ray diffraction on the crushed \u003c2mm fraction, elemental abundance of the silt/clay fraction, and U/Pb of detrital zircons in the sand fraction. Data collection will rely on established methods previously used in this region and the PIs will also explore new methods to assess their efficacy. On the same moraines crests sampled for provenance studies, the PIs will sample for cosmogenic surface exposure analyses to provide a chronologic framework at the sites for provenance changes through time. \u003cbr/\u003e\u003cbr/\u003eBroader Impact \u003cbr/\u003eThe proposed research involves graduate and undergraduate training in a diverse array of laboratory methods. Students and PIs will be make presentations to community and campus groups, as well as conduct interviews with local news outlets. The proposed work also establishes a new, potentially long-term, collaboration between scientists at IUPUI and LDEO and brings a new PI (Kaplan) into the field of Antarctic Earth Sciences.", "east": 161.2, "geometry": "POINT(5.75 -85.75)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION", "locations": null, "north": -84.1, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kaplan, Michael", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.4, "title": "Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "uid": "p0000459", "west": -149.7}, {"awards": "1142083 Kyle, Philip", "bounds_geometry": "POINT(167.15334 -77.529724)", "dataset_titles": "Database of Erebus cave field seasons; Icequakes at Erebus volcano, Antarctica; Mount Erebus Observatory GPS data; Mount Erebus Seismic Data; Mount Erebus Thermodynamic model code; Mount Erebus Volcano Observatory: Operations, Science and Outreach (MEVO-OSO); Seismic data used for high-resolution active-source seismic tomography", "datasets": [{"dataset_uid": "600381", "doi": "10.15784/600381", "keywords": "Antarctica; Cable Observatory; Cryosphere; Geology/Geophysics - Other; Infrared Imagery; IntraContinental Magmatism; MEVO; Mt Erebus; Photo/Video; Ross Island; Solid Earth; Thermal Camera; Volcano", "people": "Kyle, Philip; Oppenheimer, Clive", "repository": "USAP-DC", "science_program": "MEVO", "title": "Mount Erebus Volcano Observatory: Operations, Science and Outreach (MEVO-OSO)", "url": "https://www.usap-dc.org/view/dataset/600381"}, {"dataset_uid": "200032", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Mount Erebus Seismic Data", "url": "http://ds.iris.edu/mda/ER/"}, {"dataset_uid": "200031", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Mount Erebus Thermodynamic model code", "url": "https://github.com/kaylai/Iacovino2015_thermodynamic_model"}, {"dataset_uid": "200030", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Database of Erebus cave field seasons", "url": "https://github.com/foobarbecue/troggle"}, {"dataset_uid": "200027", "doi": "", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Mount Erebus Observatory GPS data", "url": "https://www.unavco.org/data/gps-gnss/data-access-methods/dai1/monument.php?mid=22083\u0026parent_link=Permanent\u0026pview=original"}, {"dataset_uid": "200033", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Icequakes at Erebus volcano, Antarctica", "url": "http://ds.iris.edu/mda/ZW/?timewindow=2007-2009http://ds.iris.edu/mda/Y4?timewindow=2008-2009http://ds.iris.edu/mda/ZO?timewindow=2011-2012"}, {"dataset_uid": "200034", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Seismic data used for high-resolution active-source seismic tomography", "url": "http://ds.iris.edu/mda/ZW/?timewindow=2007-2009http://ds.iris.edu/mda/Y4?timewindow=2008-2009http://ds.iris.edu/ds/nodes/dmc/forms/assembled-data/?dataset_report_number=09-015"}], "date_created": "Tue, 03 Sep 2013 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eMt. Erebus is one of only a handful of volcanoes worldwide that have lava lakes with readily observable and nearly continuous Strombolian explosive activity. Erebus is also unique in having a permanent convecting lava lake of anorthoclase phonolite magma. Over the years significant infrastructure has been established at the summit of Mt. Erebus as part of the Mount Erebus Volcano Observatory (MEVO), which serves as a natural laboratory to study a wide range of volcanic processes, especially magma degassing associated with an open convecting magma conduit. The PI proposes to continue operating MEVO for a further five years. The fundamental fundamental research objectives are: to understand diffuse flank degassing by using distributed temperature sensing and gas measurements in ice caves, to understand conduit processes, and to examine the environmental impact of volcanic emissions from Erebus on atmospheric and cryospheric environments. To examine conduit processes the PI will make simultaneous observations with video records, thermal imaging, measurements of gas emission rates and gas compositions, seismic, and infrasound data.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eAn important aspect of Erebus research is the education and training of students. Both graduate and undergraduate students will have the opportunity to work on MEVO data and deploy to the field site. In addition, this proposal will support a middle or high school science teacher for two field seasons. The PI will also continue working with various media organizations and filmmakers.", "east": 167.15334, "geometry": "POINT(167.15334 -77.529724)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e TIRS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e SPECTROMETERS \u003e FTIR SPECTROMETER; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e SPECTROMETERS \u003e DOAS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e LASER RANGING \u003e MOBLAS; IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e ELECTRON MICROPROBES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e PETROGRAPHIC MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e HRDI; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e TIRS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e INFRASONIC MICROPHONES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e AMS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e XRF; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-ES; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e LASER RANGING \u003e MOBLAS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e IRGA; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e SCANNING ELECTRON MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE CHAMBERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e SPECTROMETERS \u003e FTIR SPECTROMETER; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e MICROTOMOGRAPHY; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e SIMS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Vesuvius; lava lake; ICEQUAKES; Correlation; Strombolian eruptions; Backscattering; interferometry; Icequake coda; Degassing; thermal infrared camera; Volatiles; Magma convection; NSF; Thermodynamics; Volatile solubility; Optech; FLIR; Erebus; TREMORS; Holocene; volcanic gases; Phonolite; Vagrant; FTIR; SEISMICITY; Hydrogen emission; PASSCAL; USA/NSF; Mount Erebus; Phase equilibria; GROUND-BASED OBSERVATIONS; Alkaline volcanism; Viscosity; Infrasonic signals; Energy partitioning; cosmogenic nuclides; Active source; FIELD SURVEYS; Magma shells; OBSERVATION BASED; ERUPTIONS; MT. EREBUS; Ice caves; UV DOAS; Redox state; Anorthoclase; VOLCANO OBSERVATORY; Melt Inclusions; SEISMIC EVENTS; EARTHQUAKES; CRONUS; Explosion energy; Tomography; TLS; Radar spectra; IRIS; eruptive history; ANALYTICAL LAB", "locations": "Mount Erebus", "north": -77.529724, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kyle, Philip; Oppenheimer, Clive; Chaput, Julien; Jones, Laura; Fischer, Tobias", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e VOLCANO OBSERVATORY; OTHER \u003e MODELS \u003e OBSERVATION BASED; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "GitHub; IRIS; UNAVCO; USAP-DC", "science_programs": "MEVO", "south": -77.529724, "title": "Mount Erebus Volcano Observatory: Operations, Science and Outreach (MEVO-OSO)", "uid": "p0000383", "west": 167.15334}, {"awards": "0636818 Stone, John", "bounds_geometry": "POLYGON((-157 -85,-156 -85,-155 -85,-154 -85,-153 -85,-152 -85,-151 -85,-150 -85,-149 -85,-148 -85,-147 -85,-147 -85.3,-147 -85.6,-147 -85.9,-147 -86.2,-147 -86.5,-147 -86.8,-147 -87.1,-147 -87.4,-147 -87.7,-147 -88,-148 -88,-149 -88,-150 -88,-151 -88,-152 -88,-153 -88,-154 -88,-155 -88,-156 -88,-157 -88,-157 -87.7,-157 -87.4,-157 -87.1,-157 -86.8,-157 -86.5,-157 -86.2,-157 -85.9,-157 -85.6,-157 -85.3,-157 -85))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 05 Aug 2011 00:00:00 GMT", "description": "Hall/0636687\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to investigate late Pleistocene and Holocene changes in Scott Glacier, a key outlet glacier that flows directly into the Ross Sea just west of the present-day West Antarctic Ice Sheet (WAIS) grounding line. The overarching goals are to understand changes in WAIS configuration in the Ross Sea sector at and since the last glacial maximum (LGM) and to determine whether Holocene retreat observed in the Ross Embayment has ended or if it is still ongoing. To address these goals, moraine and drift sequences associated with Scott Glacier will be mapped and dated and ice thickness, surface velocity and surface mass balance will be measured to constrain an ice-flow model of the glacier. This model will be used to help interpret the dated geologic sequences. The intellectual merit of the project relates to gaining a better understanding of the West Antarctic Ice Sheet and how changing activity of fast-flowing outlet glaciers and ice streams exerts strong control on the mass balance of the ice sheet. Previous work suggests that grounding-line retreat in the Ross Sea continued into the late Holocene and left open the possibility of ongoing deglaciation as part of a long-term trend. Results from Reedy Glacier, an outlet glacier just behind the grounding line, suggest that retreat may have slowed substantially over the past 2000 years and perhaps even stopped. By coupling the work on Scott Glacier with recent data from Reedy Glacier, the grounding-line position will be bracketed and it should be possible to establish whether the retreat has truly ended or if it is ongoing. The broader impacts of the work relate to the societal relevance of an improved understanding of the West Antarctic ice sheet to establish how it will respond to current and possible future environmental changes. The work addresses this key goal of the West Antarctic Ice Sheet Initiative, as well as the International Polar Year focus on ice sheet history and dynamics. The work will develop future scientists through the education and training of one undergraduate and two Ph.D. students, interaction with K-12 students through classroom visits, web-based \u0027expedition\u0027 journals, letters from the field, and discussions with teachers. Results from this project will be posted with previous exposure dating results from Antarctica, on the University of Washington Cosmogenic Nuclide Lab website, which also provides information about chemical procedures and calculation methods to other scientists working with cosmogenic nuclides.", "east": -147.0, "geometry": "POINT(-152 -86.5)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -85.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Stone, John; Conway, Howard", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -88.0, "title": "Collaborative Research:Grounding-line Retreat in the Southern Ross Sea - Constraints from Scott Glacier", "uid": "p0000149", "west": -157.0}, {"awards": "0732467 Domack, Eugene", "bounds_geometry": null, "dataset_titles": "Cosmogenic-Nuclide Data at ICe-D; Expedition data of LMG0903; Expedition data of NBP1001; NBP1001 cruise data; Processed CTD 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 in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001", "datasets": [{"dataset_uid": "002715", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0903", "url": "https://www.rvdata.us/search/cruise/LMG0903"}, {"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": "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": "200297", "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": "002651", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1001", "url": "https://www.rvdata.us/search/cruise/NBP1001"}, {"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, 03 Mar 2011 00:00:00 GMT", "description": "This award supports a research cruise to perform geologic studies in the area under and surrounding the former Larsen B ice shelf, on the Antarctic Peninsula. The ice shelf\u0027s disintegration in 2002 coupled with the unique marine geology of the area make it possible to understand the conditions leading to ice shelf collapse. Bellwethers of climate change that reflect both oceanographic and atmospheric conditions, ice shelves also hold back glacial flow in key areas of the polar regions. Their collapse results in glacial surging and could cause rapid rise in global sea levels. This project characterizes the Larsen ice shelf\u0027s history and conditions leading to its collapse by determining: 1) the size of the Larsen B during warmer climates and higher sea levels back to the Eemian interglacial, 125,000 years ago; 2) the configuration of the Antarctic Peninsula ice sheet during the LGM and its subsequent retreat; 3) the causes of the Larsen B\u0027s stability through the Holocene, during which other shelves have come and gone; 4) the controls on the dynamics of ice shelf margins, especially the roles of surface melting and oceanic processes, and 5) the changes in sediment flux, both biogenic and lithogenic, after large ice shelf breakup. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eThe broader impacts include graduate and undergraduate education through research projects and workshops; outreach to the general public through a television documentary and websites, and international collaboration with scientists from Belgium, Spain, Argentina, Canada, Germany and the UK. The work also has important societal relevance. Improving our understanding of how ice shelves behave in a warming world will improve models of sea level rise.\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\".", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; 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; Larsen Ice Shelf; R/V NBP; Antarctic Peninsula; ICE SHEETS", "locations": "Antarctic Peninsula; Larsen Ice Shelf", "north": null, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Domack, Eugene Walter; Blanchette, Robert", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "ICE-D; R2R; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine and Quaternary Geosciences", "uid": "p0000841", "west": null}, {"awards": "0839042 Caffee, Marc", "bounds_geometry": "POINT(-112.085 -79.467)", "dataset_titles": "Cosmogenic 10Be in WAIS Divide Ice core, 1190-2453 m; Cosmogenic Radionuclides in the WAIS Divide Ice Core", "datasets": [{"dataset_uid": "600383", "doi": "10.15784/600383", "keywords": "Antarctica; Cosmogenic Radionuclides; Cryosphere; Geochronology; Glaciers/Ice Sheet; Glaciology; Hydrothermal Vent; WAIS divide; WAIS Divide Ice Core", "people": "Welten, Kees", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Cosmogenic Radionuclides in the WAIS Divide Ice Core", "url": "https://www.usap-dc.org/view/dataset/600383"}, {"dataset_uid": "601466", "doi": "10.15784/601466", "keywords": "Antarctica; Cryosphere; West Antarctic Ice Sheet", "people": "Welten, Kees; Caffee, M. W.; Nishiizumi, Kunihiko; Woodruff, T. E.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Cosmogenic 10Be in WAIS Divide Ice core, 1190-2453 m", "url": "https://www.usap-dc.org/view/dataset/601466"}], "date_created": "Thu, 01 Jul 2010 00:00:00 GMT", "description": "Caffee/0839042 \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 measure the concentration of the cosmogenic radionuclide, Beryllium-10 in the deep WAIS divide ice core. Since cosmogenic radionuclides are one of the key parameters used for absolute dating of the ice core and deriving paleoaccumulation rates, it is essential that these measurements be made quickly and efficiently, and that the information is disseminated as soon as the results are available. The intellectual merit of the project is that it will allow a comparison to be made between the core from WAIS Divide and previously measured cosmogenic radionuclide records from Arctic ice cores, particularly GISP2 and GRIP This project will enable scientists to delineate those processes acting at a local level from those that produce global effects and will provide independent chronological markers to aid in the reconstruction of the WAIS Divide ice core chronology. The cosmogenic 10Be profile can also be used to investigate the possible role of solar activity on climate. The direct comparison of radionuclide concentrations with paleoclimate records in ice cores from different sites will provide more insight in the timing and magnitude of solar forcing of climate. The broader impacts of this project include: (i) the formation of a multi-disciplinary team of collaborators for the interpretation of future analyses of cosmogenic radionuclide data from the WAIS divide and other ice cores. (ii) the involvement and training of graduate and undergraduate students in the large scale project of climate research through detailed studies of ice samples. (iii) the opportunity to highlight to a wide range of lab visitors and students from local K-12 schools the importance of ice core and climate change studies.\u003cbr/\u003e\u003cbr/\u003eThis award does not involve field work in Antarctica.", "east": -112.085, "geometry": "POINT(-112.085 -79.467)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e AMS", "is_usap_dc": false, "keywords": "Ice Core; Antarctica; Not provided; WAIS divide; radionuclides; accelerator mass spectrometry; Cosmogenic", "locations": "WAIS divide; Antarctica", "north": -79.467, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Welten, Kees; Nishiizumi, Kunihiko; Caffee, Marc; Woodruff, Thomas", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.467, "title": "Collaborative Research: Cosmogenic Radionuclides in the Deep WAIS Divide Core", "uid": "p0000103", "west": -112.085}, {"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": "0538683 Lal, Devendra", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Solar activity during the last millennium, estimated from cosmogenic in-situ C14 in South Pole and GISP2 ice cores", "datasets": [{"dataset_uid": "600058", "doi": "10.15784/600058", "keywords": "Antarctica; Carbon-14; Cosmos; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; solar activity; South Pole", "people": "Lal, Devendra", "repository": "USAP-DC", "science_program": null, "title": "Solar activity during the last millennium, estimated from cosmogenic in-situ C14 in South Pole and GISP2 ice cores", "url": "https://www.usap-dc.org/view/dataset/600058"}], "date_created": "Fri, 20 Feb 2009 00:00:00 GMT", "description": "0538683\u003cbr/\u003eLal\u003cbr/\u003eThis award supports a project to continue development of a new method for estimating solar activity in the past. It is based on measurements of the concentrations of in-situ produced C-14 in polar ice by cosmic rays, which depend only on (i) the cosmic ray flux, and (ii) ice accumulation rate. This is the only direct method available to date polar ice, since it does not involve any uncertain climatic transfer functions as are encountered in the applications of cosmogenic C-14 data in tree rings, or of Be-10 in ice and sediments. An important task is to improve on the temporal resolution during identified periods of high/low solar activity in the past 32 Kyr. The plan is to undertake a study of changes in the cosmic ray flux during the last millennium (1100-1825 A.D.), during which time 4 low and 1 high solar activity epoch has been identified from historical records. Sunspot data during most of these periods are sparse. Adequate ice samples are available from ice cores from the South Pole and from Summit, Greenland and a careful high resolution study of past solar activity levels during this period will be undertaken. The intellectual merit of the work includes providing independent verification of estimated solar activity levels from the two polar ice records of cosmic ray flux and greatly improve our understanding of solar-terrestrial relationships. \u003cbr/\u003eThe broader impacts include collaboration with other scientists who are experts in the application of the atmospheric cosmogenic C-14 and student training. Both undergraduates and a graduate student will be involved in the proposed research. Various forms of outreach will also be used to disseminate the results of this project, including public presentations and interactions with the media.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Lal, Devendra", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Solar Activity during the Last Millennium, Estimated from Cosmogenic in-situ 14C in South Pole and GISP2 Ice Cores", "uid": "p0000555", "west": -180.0}, {"awards": "0636629 Kurz, Mark", "bounds_geometry": "POLYGON((160.7 -77.8,161.06 -77.8,161.42 -77.8,161.78 -77.8,162.14 -77.8,162.5 -77.8,162.86 -77.8,163.22 -77.8,163.58 -77.8,163.94 -77.8,164.3 -77.8,164.3 -77.86,164.3 -77.92,164.3 -77.98,164.3 -78.04,164.3 -78.1,164.3 -78.16,164.3 -78.22,164.3 -78.28,164.3 -78.34,164.3 -78.4,163.94 -78.4,163.58 -78.4,163.22 -78.4,162.86 -78.4,162.5 -78.4,162.14 -78.4,161.78 -78.4,161.42 -78.4,161.06 -78.4,160.7 -78.4,160.7 -78.34,160.7 -78.28,160.7 -78.22,160.7 -78.16,160.7 -78.1,160.7 -78.04,160.7 -77.98,160.7 -77.92,160.7 -77.86,160.7 -77.8))", "dataset_titles": "Periglacial Landscape Evolution in Antarctic Lava Flows and Glacial Tills", "datasets": [{"dataset_uid": "600066", "doi": "10.15784/600066", "keywords": "Antarctica; Cosmogenic Radionuclides; Cryosphere; Dry Valleys; Geology/Geophysics - Other; Glaciology; LIDAR; Navigation; Sample/Collection Description", "people": "Soule, S. Adam; Kurz, Mark D.", "repository": "USAP-DC", "science_program": null, "title": "Periglacial Landscape Evolution in Antarctic Lava Flows and Glacial Tills", "url": "https://www.usap-dc.org/view/dataset/600066"}], "date_created": "Sun, 01 Feb 2009 00:00:00 GMT", "description": "This project uses cosmogenic nuclide dating and LIDAR studies of surface roughness to understand weathering and landscape evolution in the Dry Valleys of Antarctica. The work focuses on two processes: cryoturbation of frozen soils and the development of patterned, frozen ground on ancient lava flows. The approach includes innovative uses of He3 profiling. Results will also be applied to understanding the glacial history of the Dry Valleys. There are potential applications to understanding the history of the East Antarctic Ice Sheet and the formation of Martian landscapes. The broader impacts include graduate student education. As well, the work may contribute to our understanding of the history of the Antarctic ice sheets, which is important to modeling their behavior during global climate change.", "east": 164.3, "geometry": "POINT(162.5 -78.1)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION", "locations": null, "north": -77.8, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Soule, Samuel; Kurz, Mark D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.4, "title": "Periglacial Landscape Evolution in Antarctic Lava Flows and Glacial Tills", "uid": "p0000559", "west": 160.7}, {"awards": "0542293 Winckler, Gisela", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 17 Dec 2007 00:00:00 GMT", "description": "This Small Grant for Exploratory Research supports development of an innovative dating technique for application to ancient, relict ice bodies buried in the Western Dry Valleys of Antarctica. Dating of surrounding sediments and volcanic ashes indicates that these ice bodies may be up to six million years in age, offering the oldest direct atmospheric and climate records available. This SGER is a proof of concept to develop a new dating technique using beryllium (10Be) of cosmogenic origin from the atmosphere and extraterrestrial helium (3He) contained in interplanetary dust particles. Both tracers are deposited to the Earth\u0027s surface and likely incorporated into the ice matrix at constant rates. Radioactive decay of 10Be versus the stable extraterrestrial 3He signal may offer way to directly measure the age of the ice.\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": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": false, "keywords": "oldest ice on earth; IDP; cosmogenic nuclides; FIELD INVESTIGATION", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Winckler, Gisela", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": null, "title": "Direct Dating of Old Ice by Extraterrestrial Helium-3 and Atmospheric Beryllium-10 - A Proof of Concept", "uid": "p0000127", "west": null}, {"awards": "0338244 Schaefer, Joerg", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 10 Dec 2007 00:00:00 GMT", "description": "This project will determine the age, origin, and climatic significance of buried ice found in the western Dry Valleys of Antarctica. Previous studies indicate that this ice may be over a million years in age, making it by far the oldest ice yet discovered on Earth. An alternative view is that this ice is represents recently frozen groundwater. To distinguish between these hypotheses and characterize the ice, we are undertaking an interdisciplinary research program focused on: 1) understanding the surface processes that permit ice preservation; and 2) testing the efficacy of cosmogenic nuclides and 40Ar/39Ar analyses in dating both tills and volcanic ash associated with the ice. Our plan calls for the analysis of a minimum of six cosmogenic depth profiles to determine if and how cryoturbation reworks sublimation tills and assess the average rate of ice sublimation for three debris-covered glaciers. We will model through finite- element analyses at least three buried glaciers and compare flow rates with those based on radiometric dating of surface deposits. Ten ice cores will also be collected for measurement of d18O, dD, ice fabric, ice texture, total gas content/composition. Better understanding of surface processes above buried ice will permit researchers to gain access to a record of atmospheric and climate change that could well cover intervals that predate Quaternary time. The work may also add valuable insight into Martian history. In terms of broader impacts, we have recruited three female PhD students and developed interdisciplinary collaborations among geochemists at Columbia University, planetary geologists at Brown University, geomorphologists at Boston University, and numerical modelers at the University of Maine.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": false, "keywords": "FIELD INVESTIGATION", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Schaefer, Joerg", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Age, Origin and Climatic Significance of Buried Ice in the Western Dry Valleys, Antarctica", "uid": "p0000255", "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": "9909436 Farley, Kenneth", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 11 Jul 2007 00:00:00 GMT", "description": "9909436 \u003cbr/\u003eFarley\u003cbr/\u003e\u003cbr/\u003eThis award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an investigation of the uplift history of the Dry Valleys segment of the Transantarctic Mountains. The overall goal is to further constrain the exhumation history of the Transantarctic Mountains by using the newly developed apatite (U-Th)/He dating method on samples collected in vertical profiles. This approach, combined with existing apatite fission track information will constrain the rate and patterns of exhumation across the Transantarctic Mountains since their inception as a rift-flank uplift in the early Cenozoic.\u003cbr/\u003e\u003cbr/\u003eThis project will complement other projects and build on previous interpretations of the exhumation and tectonic history determined using apatite fission track thermochronology. It will bridge the gap between information on erosion rates determined from fission track thermochronology and from cosmogenic surface exposure dating and integrate the exhumation history of the mountains with their landscape evolution. As such, the results from this project will address an outstanding problem in Antarctic science; namely the stability of the East Antarctic Ice Sheet, and the timing of the transition from a \"warm\" dynamic ice sheet to a cold polar ice sheet. Highly relevant to this issue is the landscape evolution of the Transantarctic Mountains because many diverse lines of evidence for the rate of landscape evolution have been used to argue for a dynamic ice sheet up until either the Pliocene (the \"dynamic\" ice sheet model) or the middle Miocene (the \"stable\" ice sheet model). Understanding the past stability or dynamic fluctuations of the East Antarctic ice sheet with respect to the climate record is, of course, important for understanding how the present ice sheet may respond to global warming.\u003cbr/\u003e\u003cbr/\u003eThe specific objective of this project is to determine apatite (U-Th)/He age versus elevation trends for a number of vertical profiles from locations within the Transantarctic Mountain front and across the structural grain of the range. Fission track data already exist for all of these profiles, with apatite fission track ages ranging from 150-30 Ma. The greater precision of the (U-Th)/He technique and the fact it records information at lower temperatures (closure temperature of ~70 degrees Celsius; limits of 40-85 degrees Celsius for the He partial retention zone) will allow examination of the exhumation history of the TAM in more detail from ca 130 Ma to ~20 Ma. Another facet is to examine areas where Cretaceous exhumation is recorded and areas where the fission track profiles indicate periods of thermal and tectonic stability and minimal erosion throughout the Cretaceous. The variation of timing of the onset of more rapid exhumation accompanying uplift and formation of the Transantarctic Mountains in the early Cenozoic will also be examined.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Farley, Kenneth", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Exhumation of the Transantarctic Mountains: Constraints from (U-Th)/He Dating of Apatites", "uid": "p0000281", "west": null}, {"awards": "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": "9909484 Lal, Devendra", "bounds_geometry": "POINT(106.133 -76.083)", "dataset_titles": null, "datasets": null, "date_created": "Mon, 02 Oct 2006 00:00:00 GMT", "description": "This award is for support for three years of funding to develop a history of snow accumulation and physical processes occurring in the upper layers of ice deposited at several sites in Antarctica, using cosmogenic in-situ Carbon-14 (14C) and cosmogenic Beryllium-10 (10Be) as radiotracers. The proposed research emerges from recent studies of cosmogenic in-situ 14C in GISP2 Holocene and several Antarctic ice samples, which revealed marked differences in the 14C concentrations in the samples, compared to the theoretically expected values. The GISP2 samples have about the expected amount of 14C but the Antarctic samples are deficient by 30-50% or more. These results suggest that in slowly accumulating ice samples (such as occur in Antarctica), the cosmic ray implanted 14C is somehow partially lost, but quantitatively preserved in samples from areas of high accumulation. These results suggest that after deposition of the cosmogenic 14C, its concentration is decreased in firn due to processes such as recrystallization, sublimation/evaporation and redeposition. In order to quantify these processes, the atmospheric cosmogenic 10Be in ice samples will also be measured. Since 10Be and 14C have different responses to the firnification processes, their simultaneous study can help to elucidate the nature and importance of these processes. Samples from Taylor Dome, Vostok and Siple Dome will all be studied.", "east": 106.133, "geometry": "POINT(106.133 -76.083)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided; Cosmogenic 14 C ; Firn; Holocene; Taylor Dome; Vostok; Siple Dome; radiotracers; Carbon-14; 10Be; Accumulation processes", "locations": "Siple Dome; Taylor Dome; Vostok", "north": -76.083, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Lal, Devendra", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -76.083, "title": "Firn Accumulation Processes in Taylor Dome, Vostok and Siple Dome Ice Using Cosmogenic 14 C and 10Be as Tracers", "uid": "p0000732", "west": 106.133}, {"awards": "0126343 Nishiizumi, Kunihiko", "bounds_geometry": "POINT(-148.812 -81.6588)", "dataset_titles": "Cosmogenic Radionuclides in the Siple Dome A Ice Core", "datasets": [{"dataset_uid": "609307", "doi": "10.7265/N5XK8CGS", "keywords": "Antarctica; Cryosphere; Geochemistry; Geochronology; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Nishiizumi, Kunihiko; Finkel, R. C.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Cosmogenic Radionuclides in the Siple Dome A Ice Core", "url": "https://www.usap-dc.org/view/dataset/609307"}], "date_created": "Mon, 12 Jun 2006 00:00:00 GMT", "description": "This award supports a three-year renewal project to complete measurement of cosmogenic nuclides in the Siple Dome ice core as part of the West Antarctic ice core program. The investigators will continue to measure profiles of Beryllium-10 (half-life = 1.5x10 6 years) and Chlorine-36 (half-life = 3.0x10 5 years) in the entire ice core which spans the time period from the present to about 100 kyr. It will be particularly instructive to compare the Antarctic record with the detailed Arctic record that was measured by these investigators as part of the GISP2 project. This comparison will help separate global from local effects at the different drill sites. Cosmogenic radionuclides in polar ice cores have been used to study the long-term variations in several important geophysical variables, including solar activity, geomagnetic field strength, atmospheric circulation, snow accumulation rates, and others. The time series of nuclide concentrations resulting from this work will be applied to several problem areas: perfecting the ice core chronology, deducing the history of solar activity, deducing the history of variations in the geomagnetic field, and studying the possible role of solar variations on climate. Comparison of Beryllium-10 and Chlorine-36 profiles in different cores will allow us to improve the ice core chronology and directly compare ice cores from different regions of the globe. Additional comparison with the Carbon-14 record will allow correlation of the ice core paleoenvironment record to other, Carbon-14 dated, paleoclimate records.", "east": -148.812, "geometry": "POINT(-148.812 -81.6588)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e AMS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "AGDC; Ice Core Chemistry; Antarctica; Ice Core; Chlorine-36; Cosmogenic nuclide; OPP-0126343; GROUND STATIONS; Beryllium-10; Siple Dome; West Antarctica", "locations": "Antarctica; Siple Dome; West Antarctica", "north": -81.6588, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Finkel, R. C.; Nishiizumi, Kunihiko", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.6588, "title": "Cosmogenic Radionuclides in the Siple Dome Ice Core", "uid": "p0000358", "west": -148.812}, {"awards": null, "bounds_geometry": null, "dataset_titles": "Cosmogenic nuclide data for bedrock samples from the Ford Ranges, Marie Byrd Land, West Antarctica", "datasets": [{"dataset_uid": "600002", "doi": "", "repository": "USAP-DC", "science_program": null, "title": "Cosmogenic nuclide data for bedrock samples from the Ford Ranges, Marie Byrd Land, West Antarctica", "url": "http://www.usap-dc.org/view/dataset/600002"}], "date_created": "Wed, 06 Apr 2005 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": "Stone, John", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "9017827 Lal, Devendra", "bounds_geometry": null, "dataset_titles": "Dome C Ice Core Chemistry and Depth and Age Scale Data", "datasets": [{"dataset_uid": "609243", "doi": "", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Depth-Age; Dome C Ice Core; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate", "people": "Lal, Devendra; Lorius, Claude", "repository": "USAP-DC", "science_program": "Dome C Ice Core", "title": "Dome C Ice Core Chemistry and Depth and Age Scale Data", "url": "https://www.usap-dc.org/view/dataset/609243"}], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": "This award is for support of a study to establish a quantitative nuclear method for determination of Antarctic ablation and accumulation rates and to provide correction factors for the carbon 14 ages of ice samples dated using trapped carbon 14. Recent studies have established the presence of cosmogenic in-situ produced carbon 14 in polar ice. In conjunction with estimated carbon 14 production rates, measured concentrations of carbon 14 per gram of ice yield, ablation rates which are in good agreement with the values determined from stake measurements. Similar studies to determine accumulation rates have been tested and the estimates are consistent with previous studies. This study will expand the preliminary work done to date in order to improve the 14CO and 14CO2 vacuum extraction techniques, by lowering blank levels and by obtaining more complete separation of 14CO and 14CO2.", "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": "Lal, Devendra; Lorius, Claude; Lal, Devendra", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Dome C Ice Core", "south": null, "title": "Nuclear Studies of Accumulating and Ablation Ice Using Cosmogenic 14c", "uid": "p0000152", "west": null}]

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