USAP-DC

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

[{"awards": "2037963 Smith, Heidi", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 11 Oct 2022 00:00:00 GMT", "description": "Glacial ice cores serve as a museum back in time, providing detailed records of past climatic conditions. In addition to chronological records such as temperature, chemistry and gas composition, ice provides a unique environment for preserving microbes and other biological materials through time. These microbes provide invaluable insight into the physiological capabilities necessary for survival in the Earths cryosphere and other icy planetary bodies, yet little is known about them. This award supports fundamental research into the activity of microbes in ice, and directly supports major research priorities regarding Antarctic biota identified in the 2015 National Academies of Sciences, Engineering, and Medicine report, A Strategic Vision for NSF Investments in Antarctic and Southern Ocean Research. The broader impacts of this work are that it will be relevant to researchers across paleoclimate and biological fields. It will support two early career researchers, a graduate and an undergraduate student who will conduct laboratory analyses, participate in outreach activities, publish papers in scientific journals and present at conferences. \r\n\r\nThis work will use previously collected ice cores to investigate englacial microbial activity from the Holocene back to the Last Glacial Maximum from the blue ice area of Taylor Glacier, Antarctica. The proposal identified making significant contributions to 1) investing how Antarctic organisms evolve and adapt to changing environment, 2) understanding how microbes alter the preservation of paleorecord-relevant gas and trace element information in ice cores, and 3) identifying microbial life in cores and their activity in relation to dust depositional events. Two recently developed complementary techniques (bio-orthogonal noncanonical amino acid tagging and deuterium isotope probing) in combination with Raman Confocal Microspectroscopy will be used to assess and quantify microbial activity in ice. During phase one of the project, these methods will be optimized using deaccessioned ice cores available at the National Science Foundations Ice Core Facility. In phase two, ice cores in a time series from the Taylor Glacier will be analyzed for geochemistry and microbial activity. Research results will provide a comprehensive view of englacial microbial communities, including their metabolic diversity and activity, and the effect of geochemical parameters on microbial assemblages from different climate periods. Given the dearth of information available on englacial microbial communities, the results of this research will be of particular significance.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Microbial Activity; LABORATORY; Paleoclimate; CAMP; Taylor Glacier; Microbiology; Alaska; ICE CORE RECORDS", "locations": "CAMP; Alaska; Taylor Glacier", "north": null, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Smith, Heidi; Foreman, Christine; Dieser, Markus", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "Life in Ice: Probing Microbial Englacial Activity through Time", "uid": "p0010385", "west": null}, {"awards": "1644118 Dunbar, Robert", "bounds_geometry": "POLYGON((-108 -73,-107.3 -73,-106.6 -73,-105.9 -73,-105.2 -73,-104.5 -73,-103.8 -73,-103.1 -73,-102.4 -73,-101.7 -73,-101 -73,-101 -73.3,-101 -73.6,-101 -73.9,-101 -74.2,-101 -74.5,-101 -74.8,-101 -75.1,-101 -75.4,-101 -75.7,-101 -76,-101.7 -76,-102.4 -76,-103.1 -76,-103.8 -76,-104.5 -76,-105.2 -76,-105.9 -76,-106.6 -76,-107.3 -76,-108 -76,-108 -75.7,-108 -75.4,-108 -75.1,-108 -74.8,-108 -74.5,-108 -74.2,-108 -73.9,-108 -73.6,-108 -73.3,-108 -73))", "dataset_titles": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020", "datasets": [{"dataset_uid": "601611", "doi": "10.15784/601611", "keywords": "Amundsen Sea; Antarctica; Chemistry:Water; CTD; D18O; NBP0001; NBP0702; NBP0901; NBP1901; NBP2002; Oceans; Oxygen Isotope; R/v Nathaniel B. Palmer; Seawater Isotope; Southern Ocean", "people": "Hennig, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020", "url": "https://www.usap-dc.org/view/dataset/601611"}], "date_created": "Wed, 21 Sep 2022 00:00:00 GMT", "description": "Estimating Antarctic ice sheet growth or loss is important to predicting future sea level rise. Such estimates rely on field measurements or remotely sensed based observations of the ice sheet surface, ice margins, and or ice shelves. This work examines the introduction of freshwater into the ocean to surrounding Antarctica to track meltwater from continental ice. Polar ice is depleted in two stable isotopes, 18O and D, deuterium, relative to Southern Ocean seawater and precipitation. Measurements of seawater isotopic composition in conjunction with precise observations of seawater temperature and salinity, will permit discrimination of freshwater derived from melting glacial ice from that derived from regional precipitation or sea ice melt.\u003cbr/\u003e\u003cbr/\u003eThis research describes an accepted method for determining rates and locations of meltwater entering the oceans from polar ice sheets. As isotopic and salinity perturbations are cumulative in many Antarctic coastal seas, the method allows for the detection of any marked acceleration in meltwater introduction in specific regions, using samples collected and analyzed over a period of years to decades. Impact of the project derives from use of an independent method capable of constraining knowledge about current ice sheet melt rates, their stability and potential impact on sea level rise. The project allows for sample collection taken from foreign vessels of opportunity sailing in Antarctic waters, and subsequent sharing and interpretation of data. Research partners include the U.S., Korea, China, New Zealand, the United Kingdom, and Germany. Participating collaborators will collect seawater samples for isotopic and salinity analysis at Stanford University. USAP cruises will concentrate on sampling the Ross Sea, and the West Antarctic. The work plan includes interpretation of isotopic data using box model and mixing curve analyses as well as using isotope enabled ROMS (Regional Ocean Modeling System) models. The broader impacts of the research will include development of an educational module that illustrates the scientific method and how ocean observations help society understand how Earth is changing.", "east": -101.0, "geometry": "POINT(-104.5 -74.5)", "instruments": null, "is_usap_dc": true, "keywords": "Stable Isotopes; WATER TEMPERATURE; SALINITY; Oxygen Isotope; Meltwater Inventory; Pine Island Bay; OCEAN CHEMISTRY", "locations": "Pine Island Bay", "north": -73.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Dunbar, Robert", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.0, "title": "Estimation of Antarctic Ice Melt using Stable Isotopic Analyses of Seawater", "uid": "p0010380", "west": -108.0}, {"awards": "2035580 Aarons, Sarah; 2035637 Tabor, Clay", "bounds_geometry": null, "dataset_titles": "Concentration and flux of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area.; Oxygen and hydrogen isotope compositions of ice from ALHIC1903 drilled at the Allan Hills Blue Ice Area.; Rare earth elemental concentrations of leached ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area.; Strontium and neodymium isotope compositions of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area.", "datasets": [{"dataset_uid": "601751", "doi": "10.15784/601751", "keywords": "ALHIC1903; Allan Hills; Antarctica; Deuterium; Glaciology; Hydrogen; Ice; Ice Core Data; Ice Core Records; Isotope; Oxygen; Snow/ice; Snow/Ice; Water", "people": "Carter, Austin", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Oxygen and hydrogen isotope compositions of ice from ALHIC1903 drilled at the Allan Hills Blue Ice Area.", "url": "https://www.usap-dc.org/view/dataset/601751"}, {"dataset_uid": "601750", "doi": "10.15784/601750", "keywords": "ALHIC1903; Allan Hills; Antarctica; Blue Ice; Dust; Glaciology; Ice Core Records; Leach; Rare Earth Element; Snow/ice; Snow/Ice", "people": "Carter, Austin", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Rare earth elemental concentrations of leached ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area.", "url": "https://www.usap-dc.org/view/dataset/601750"}, {"dataset_uid": "601749", "doi": "10.15784/601749", "keywords": "ALHIC1903; Allan Hills; Antarctica; Dust; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Isotope; Nd; Neodymium; Snow/ice; Snow/Ice; Sr; Strontium", "people": "Carter, Austin", "repository": "USAP-DC", "science_program": null, "title": "Strontium and neodymium isotope compositions of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area.", "url": "https://www.usap-dc.org/view/dataset/601749"}, {"dataset_uid": "601748", "doi": "10.15784/601748", "keywords": "ALHIC1903; Allan Hills; Antarctica; Blue Ice; Concentration; Dust; Flux; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Snow/ice; Snow/Ice", "people": "Carter, Austin", "repository": "USAP-DC", "science_program": null, "title": "Concentration and flux of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area.", "url": "https://www.usap-dc.org/view/dataset/601748"}], "date_created": "Wed, 06 Oct 2021 00:00:00 GMT", "description": "The spatial extent of the West Antarctic Ice Sheet during the last interglacial period (129,000 to 116,000 years ago) is currently unknown, yet this information is fundamental to projections of the future stability of the ice sheet in a warming climate. Paleoclimate records and proxy evidence such as dust can inform on past environmental conditions and ice-sheet coverage. This project will combine new, high-sensitivity geochemical measurements of dust from Antarctic ice collected at Allan Hills with existing water isotope records to document climate and environmental changes through the last interglacial period. These changes will then be compared with Earth-system model simulations of dust and water isotopes to determine past conditions and constrain the sensitivity of the West Antarctic Ice Sheet to warming. The project will test the hypothesis that the uncharacteristically volcanic dust composition observed at another peripheral ice core site at Taylor Glacier during the last interglacial period is related to changes in the spatial extent of the West Antarctic Ice Sheet.\r\n\r\nThis project aims to characterize mineral dust transport during the penultimate glacial-interglacial transition. The team will apply high-precision geochemical techniques to the high-volume, high-resolution ice core drilled at the Allan Hills site in combination with Earth system model simulations to: (1) determine if the volcanic dust signature found in interglacial ice from Taylor Glacier is also found at Allan Hills, (2) determine the likely dust source(s) to this site during the last interglacial, and (3) probe the atmospheric and environmental changes during the last interglacial with a diminished West Antarctic Ice Sheet. The team will develop a suite of measurements on previously drilled ice from Allan Hills, including isotopic compositions of Strontium and Neodymium, trace element concentrations, dust-size distribution, and imaging of ice-core dust to confirm the original signal observed and provide a broader spatial reconstruction of dust transport. In tandem, the team will conduct Earth system modeling with prognostic dust and water-isotope capability to test the sensitivity of dust transport under several plausible ice-sheet and freshwater-flux configurations. By comparing dust reconstruction and model simulations, the team aims to elucidate the driving mechanisms behind dust transport during the last interglacial period.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "MICROPARTICLE CONCENTRATION; FIELD SURVEYS; GEOCHEMISTRY; ICE EXTENT; Amd/Us; USA/NSF; PALEOCLIMATE RECONSTRUCTIONS; AMD; Allan Hills; ICE CORE RECORDS; USAP-DC", "locations": "Allan Hills", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Aarons, Sarah; Tabor, Clay", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Peripheral East Antarctic ice as a unique recorder of climate variability during the Last Interglacial", "uid": "p0010270", "west": null}, {"awards": "1807522 Jones, Tyler", "bounds_geometry": "POINT(-112.085 -79.467)", "dataset_titles": "Mid-Holocene high-resolution water isotope time series for the WAIS Divide ice core; Seasonal temperatures in West Antarctica during the Holocene ; Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "datasets": [{"dataset_uid": "601603", "doi": "10.15784/601603", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Seasonality; Seasonal Temperatures; Temperature; Water Isotopes; West Antarctic Ice Sheet", "people": "Jones, Tyler R.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Seasonal temperatures in West Antarctica during the Holocene ", "url": "https://www.usap-dc.org/view/dataset/601603"}, {"dataset_uid": "601326", "doi": "10.15784/601326", "keywords": "Antarctica; Delta 18O; Delta Deuterium; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Snow/ice; Snow/Ice; WAIS Divide Ice Core; Water Isotopes; West Antarctic Ice Sheet", "people": "White, James; Jones, Tyler R.; Vaughn, Bruce; Morris, Valerie", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Mid-Holocene high-resolution water isotope time series for the WAIS Divide ice core", "url": "https://www.usap-dc.org/view/dataset/601326"}, {"dataset_uid": "601274", "doi": "10.15784/601274", "keywords": "Antarctica; Delta 18O; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Snow/ice; Snow/Ice; WAIS Divide; WAIS Divide Ice Core; West Antarctic Ice Sheet", "people": "Jones, Tyler R.; White, James; Vaughn, Bruce; Bradley, Elizabeth; Morris, Valerie; Price, Michael; Garland, Joshua", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "url": "https://www.usap-dc.org/view/dataset/601274"}], "date_created": "Tue, 26 May 2020 00:00:00 GMT", "description": "Ice cores contain detailed accounts of Earth\u0027s climate history. The collection of an ice core can be logistically challenging, and extraction of data from the core can be time-consuming as well as susceptible to both human and machine error. Furthermore, locked in measurements from ice cores is information that scientists have not yet found ways to recover. This project will apply techniques from information theory to ice-core data to unlock that information. The primary goal is to demonstrate that information theory can (a) identify regions of a specific ice-core record that are in need of further analysis and (b) provide some specific guidance for that analysis. A secondary goal is to demonstrate that information theory has practical and scientific utility for studies of past climate. This project aims to use information theory in two distinct ways: first, to identify regions of a core where information appears to be damaged or missing, perhaps due to human and/or machine error. In the segment of the West Antarctic Ice Sheet Divide core that is 5000-8000 years old, for instance, information-theoretic methods reveal significant levels of noise, probably due to a laboratory instrument, and something that was not visible in the raw data. This is a particularly important segment of the record, as it contains valuable clues about climatic shifts and the onset of the Holocene. Targeted re-sampling of this segment of the core and reanalysis with newer laboratory apparatus could resolve the data issues. The second way in which information theory can potentially aid in ice-core analysis is by extracting climate signals from the data--such as the accumulation rate at the core site over the period of its formation. This quantity usually requires significant time and effort to produce, but information theory could help to streamline that process.This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -112.085, "geometry": "POINT(-112.085 -79.467)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "AMD; West Antarctic Ice Sheet; ISOTOPES; Amd/Us; USAP-DC; USA/NSF; Water Isotopes; WAIS Divide Ice Core; Deuterium; LABORATORY", "locations": "West Antarctic Ice Sheet", "north": -79.467, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Garland, Joshua; Jones, Tyler R.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.467, "title": "Collaborative Research: Targeted resampling of deep polar ice cores using information theory", "uid": "p0010100", "west": -112.085}, {"awards": "1443105 Steig, Eric", "bounds_geometry": "POINT(0 -90)", "dataset_titles": "Continuous-flow measurements of the complete water isotope ratios (D/H, 17O/16O, 18O/16) from the South Pole ice core; South Pole high resolution ice core water stable isotope record for dD, d18O; South Pole Ice Core Holocene Major Ion Dataset; SP19 Gas Chronology; Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "datasets": [{"dataset_uid": "601399", "doi": "10.15784/601399", "keywords": "Antarctica; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Holocene Major Ion Dataset", "url": "https://www.usap-dc.org/view/dataset/601399"}, {"dataset_uid": "601239", "doi": "10.15784/601239", "keywords": "Antarctica; Cavity Ring Down Spectrometers; Delta 18O; Delta Deuterium; Deuterium Isotopes; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core; Ice Core Chemistry; Ice Core Data; Oxygen Isotope; Snow/ice; Snow/Ice; Stable Isotopes", "people": "Kahle, Emma; Schauer, Andrew; Jones, Tyler R.; Vaughn, Bruce; Morris, Valerie; White, James; Steig, Eric J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole high resolution ice core water stable isotope record for dD, d18O", "url": "https://www.usap-dc.org/view/dataset/601239"}, {"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}, {"dataset_uid": "601396", "doi": "10.15784/601396", "keywords": "Accumulation; Antarctica; Diffusion Length; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Dynamic; Layer Thinning; Oxygen Isotope; South Pole; SPICEcore; Temperature", "people": "Epifanio, Jenna; Jones, Tyler R.; Steig, Eric J.; Conway, Howard; Kahle, Emma; Buizert, Christo; Vaughn, Bruce; Waddington, Edwin D.; Morris, Valerie; Koutnik, Michelle; Schauer, Andrew; White, James; Stevens, Max; Fudge, T. J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "url": "https://www.usap-dc.org/view/dataset/601396"}, {"dataset_uid": "601429", "doi": "10.15784/601429", "keywords": "Antarctica; Climate; Deuterium; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hydrogen; Ice; Ice Core; Ice Core Chemistry; Oxygen; Paleoclimate; Snow/ice; Snow/Ice; South Pole; Stable Isotopes", "people": "Jones, Tyler R.; Steig, Eric J.; Schauer, Andrew; Kahle, Emma; Morris, Valerie; Vaughn, Bruce; White, James", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Continuous-flow measurements of the complete water isotope ratios (D/H, 17O/16O, 18O/16) from the South Pole ice core", "url": "https://www.usap-dc.org/view/dataset/601429"}], "date_created": "Sun, 17 Nov 2019 00:00:00 GMT", "description": "This project will develop a record of the stable-isotope ratios of water from an ice core at the South Pole, Antarctica. Water-isotope ratio measurements provide a means to determine variability in temperature through time. South Pole is distinct from most other locations in Antarctica in showing no warming in recent decades, but little is known about temperature variability in this location prior to the installation of weather stations in 1957. The measurements made as part of this project will result in a much longer temperature record, extending at least 40,000 years, aiding our ability to understand what controls Antarctic climate, and improving projections of future Antarctic climate change. Data from this project will be critical to other investigators working on the South Pole ice core, and of general interest to other scientists and the public. Data will be provided rapidly to other investigators and made public as soon as possible.\u003cbr/\u003e\u003cbr/\u003eThis project will obtain records of the stable-isotope ratios of water on the ice core currently being obtained at South Pole. The core will reach a depth of 1500 m and an age of 40,000 years. The project will use laser spectroscopy to obtain both an ultra-high-resolution record of oxygen 18/16 and deuterium-hydrogen ratios, and a lower-resolution record of oxygen 17/16 ratios. The high-resolution measurements will be used to aid in dating the core, and to provide estimates of isotope diffusion that constrain the process of firn densification. The novel 17/16 measurement provides additional constraints on the isotope fractionation due to the temperature-dependent supersaturation ratio, which affects the fractionation of water during the liquid-solid condensate transition. Together, these techniques will allow for improved accuracy in the use of the water isotope ratios as proxies for ice-sheet temperature, sea-surface temperature, and atmospheric circulation. The result will be a record of decadal through centennial and millennial scale climate change in a climatically distinct region in East Antarctica that has not been previously sampled by deep ice coring. The project will support a graduate student who will be co-advised by faculty at the University of Washington and the University of Colorado, and will be involved in all aspects of the work.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "SPICEcore; D18O; LABORATORY; OXYGEN ISOTOPE ANALYSIS; Oxygen Isotope; South Pole; USAP-DC; GLACIERS/ICE SHEETS; Antarctica; AMD; FIELD INVESTIGATION; Ice Core", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Steig, Eric J.; White, James", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: Record of the Triple-oxygen Isotope and Hydrogen Isotope Composition of Ice from an Ice Core at South Pole", "uid": "p0010065", "west": 0.0}, {"awards": "1443306 Mayewski, Paul; 1443263 Higgins, John", "bounds_geometry": null, "dataset_titles": "Carbon dioxide concentration and its stable carbon isotope composition in Allan Hills ice cores; Elemental and isotopic composition of heavy noble gases in Allan Hills ice cores; Elemental and isotopic composition of nitrogen, oxygen, and argon in Allan Hills ice cores; Greenhouse gas composition in the Allan Hills S27 ice core; Methane concentration in Allan Hills ice cores; Stable isotope composition of the trapped air in the Allan Hills S27 ice core; Stable water isotope data for the AH-1502 ice core drilled at the Allan Hills Blue ice area; Stable water isotope data for the AH-1503 ice core drilled at the Allan Hills Blue ice area; Stable water isotope data for the surface samples collected at the Allan Hills Blue ice area", "datasets": [{"dataset_uid": "601203", "doi": "10.15784/601203", "keywords": "Allan Hills; Allan Hills Project; Antarctica; Chemistry:ice; Chemistry:Ice; Gas Chromatography; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenhouse Gas; Ice; Ice Core Data; Ice Core Gas Records; Methane; Snow/ice; Snow/Ice", "people": "Higgins, John; Bender, Michael; Brook, Edward J.; Yan, Yuzhen", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Methane concentration in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601203"}, {"dataset_uid": "601512", "doi": "10.15784/601512", "keywords": "Allan Hills; Antarctica; Blue Ice; Ice Core; Ice Core Gas Records; Isotope; Nitrogen; Oxygen", "people": "Yan, Yuzhen; Higgins, John; Bender, Michael", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable isotope composition of the trapped air in the Allan Hills S27 ice core", "url": "https://www.usap-dc.org/view/dataset/601512"}, {"dataset_uid": "601201", "doi": "10.15784/601201", "keywords": "Allan Hills; Allan Hills Project; Antarctica; Argon; Chemistry:ice; Chemistry:Ice; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Data; Ice Core Gas Records; Krypton; Mass Spectrometer; Noble Gas; Snow/ice; Snow/Ice; Xenon", "people": "Severinghaus, Jeffrey P.; Bender, Michael; Higgins, John; Ng, Jessica; Yan, Yuzhen", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Elemental and isotopic composition of heavy noble gases in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601201"}, {"dataset_uid": "601483", "doi": "10.15784/601483", "keywords": "Allan Hills; Antarctica; Argon; Ice; Ice Core Data; Ice Core Gas Records; Isotope; Mass Spectrometry; Nitrogen; Oxygen", "people": "Bender, Michael; Higgins, John; Yan, Yuzhen", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Elemental and isotopic composition of nitrogen, oxygen, and argon in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601483"}, {"dataset_uid": "601130", "doi": "10.15784/601130", "keywords": "Allan Hills; Allan Hills Project; Antarctica; Blue Ice; Chemistry:ice; Chemistry:Ice; Delta 18O; Delta Deuterium; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Gas Records; Ice Core Records; Oxygen; Snow/ice; Snow/Ice; Stable Water Isotopes; Transantarctic Mountains", "people": "Mayewski, Paul A.; Yan, Yuzhen; Introne, Douglas; Kurbatov, Andrei V.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable water isotope data for the surface samples collected at the Allan Hills Blue ice area", "url": "https://www.usap-dc.org/view/dataset/601130"}, {"dataset_uid": "601129", "doi": "10.15784/601129", "keywords": "Allan Hills; Allan Hills Project; Antarctica; Blue Ice; Delta 18O; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Isotope Data; Oxygen; Snow/ice; Snow/Ice; Stable Water Isotopes; Transantarctic Mountains", "people": "Kurbatov, Andrei V.; Yan, Yuzhen; Introne, Douglas; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable water isotope data for the AH-1502 ice core drilled at the Allan Hills Blue ice area", "url": "https://www.usap-dc.org/view/dataset/601129"}, {"dataset_uid": "601128", "doi": "10.15784/601128", "keywords": "Allan Hills; Antarctica; Blue Ice; Chemistry:ice; Chemistry:Ice; Delta 18O; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope Record; Mass Spectrometry; Stable Water Isotopes", "people": "Kurbatov, Andrei V.; Yan, Yuzhen; Introne, Douglas; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable water isotope data for the AH-1503 ice core drilled at the Allan Hills Blue ice area", "url": "https://www.usap-dc.org/view/dataset/601128"}, {"dataset_uid": "601425", "doi": "10.15784/601425", "keywords": "Allan Hills; Antarctica; Blue Ice; Carbon Dioxide; Ice Core; Methane", "people": "Yan, Yuzhen; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Greenhouse gas composition in the Allan Hills S27 ice core", "url": "https://www.usap-dc.org/view/dataset/601425"}, {"dataset_uid": "601202", "doi": "10.15784/601202", "keywords": "Allan Hills; Allan Hills Project; Antarctica; Carbon Dioxide; Carbon Isotopes; Chemistry:ice; Chemistry:Ice; CO2; Gas Chromatography; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Data; Ice Core Gas Records; Ice Core Records; Mass Spectrometer; Mass Spectrometry; Methane; Snow/ice; Snow/Ice", "people": "Higgins, John; Yan, Yuzhen; Brook, Edward J.; Bender, Michael", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Carbon dioxide concentration and its stable carbon isotope composition in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601202"}], "date_created": "Thu, 18 Oct 2018 00:00:00 GMT", "description": "Bubbles of ancient air trapped in ice cores permit the direct reconstruction of atmospheric composition and allow us to link greenhouse gases and global climate over the last 800,000 years. Previous field expeditions to the Allan Hills blue ice area, Antarctica, have recovered ice cores that date to one million years, the oldest ice cores yet recovered from Antarctica. These records have revealed that interglacial CO2 concentrations decreased by 800,000 years ago and that, in the warmer world 1 million years ago, CO2 and Antarctic temperature were linked as during the last 800,000 years. This project will return to the Allan Hills blue ice area to recover additional ice cores that date to 1 million years or older. The climate records developed from the drilled ice cores will provide new insights into the chemical composition of the atmosphere and Antarctic climate during times of comparable or even greater warmth than the present day. Our results will help answer questions about issues associated with anthropogenic change. These include the relationship between temperature change and the mass balance of Antarctic ice; precipitation and aridity variations associated with radiatively forced climate change; and the climate significance of sea ice extent. The project will entrain two graduate students and a postdoctoral scholar, and will conduct outreach including workshops to engage teachers in carbon science and ice cores.\u003cbr/\u003e\u003cbr/\u003eBetween about 2.8-0.9 million years ago, Earth\u0027s climate was characterized by 40,000-year cycles, driven or paced by changes in the tilt of Earth\u0027s spin axis. Much is known about the \"40,000-year\" world from studies of deep-sea sediments, but our understanding of climate change during this period is incomplete because we lack records of Antarctic climate and direct records of atmospheric greenhouse gas concentrations. We propose to address these issues by building on our recent studies of ancient ice from the Main Ice Field, Allan Hills, Antarctica. During previous field seasons we recovered ice extending, discontinuously, from 0.1-1.0 million years old. Ice was dated by measuring the 40Ar/38Ar (Argon) ratio of the trapped gases. Our discovery of million year-old ice demonstrates that there is gas-record-quality ice from the 40,000-year world in the Allan Hills Main Ice Field. We have identified two different sites, each overlying bedrock at ~ 200 m depth, that are attractive targets for coring ice dating to 1 million years and older. This project aims to core the ice at these two sites, re-occupy a previous site with million year-old ice and drill it down to the bedrock, and generate 10-20 short (~10-meter) cores in areas where our previous work and terrestrial meteorite ages suggest ancient surface ice. We plan to date the ice using the 40Ar/38Ar ages of trapped Argon. We also plan to characterize the continuity of our cores by measuring the deuterium and oxygen isotope ratios in the ice, methane, ratios of Oxygen and Argon to Nitrogen in trapped gas, the Nitrogen-15 isotope (d15N) of Nitrogen, and the Oxygen-18 isotope (d18O) of Oxygen. As the ice may be stratigraphically disturbed, these measurements will provide diagnostic properties for assessing the continuity of the ice-core records. Successful retrieval of ice older than one million years will provide the opportunity for follow-up work to measure the CO2 concentration and other properties within the ice to inform on the temperature history of the Allan Hills region, dust sources and source-area aridity, moisture sources, densification conditions, global average ocean temperature, and greenhouse gas concentrations. We will analyze the data in the context of leading hypotheses of the 40,000-year world and the Mid-Pleistocene Transition to the 100,000-year world. We expect to advance understanding of climate dynamics during these periods.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Amd/Us; AMD; Allan Hills; USA/NSF; FIELD INVESTIGATION; USAP-DC; Ice Core; LABORATORY", "locations": "Allan Hills", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Mayewski, Paul A.; Kurbatov, Andrei V.; Higgins, John; Bender, Michael", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": null, "title": "Collaborative Research: Window into the World with 40,000-year Glacial Cycles from Climate Records in Million Year-old Ice from the Allan Hills Blue Ice Area", "uid": "p0000760", "west": null}, {"awards": "0838849 Bender, Michael; 0838843 Kurbatov, Andrei", "bounds_geometry": "POLYGON((159.16667 -76.66667,159.19167 -76.66667,159.21667 -76.66667,159.24167 -76.66667,159.26667 -76.66667,159.29167 -76.66667,159.31667 -76.66667,159.34167 -76.66667,159.36667 -76.66667,159.39167 -76.66667,159.41667 -76.66667,159.41667 -76.673336,159.41667 -76.680002,159.41667 -76.686668,159.41667 -76.693334,159.41667 -76.7,159.41667 -76.706666,159.41667 -76.713332,159.41667 -76.719998,159.41667 -76.726664,159.41667 -76.73333,159.39167 -76.73333,159.36667 -76.73333,159.34167 -76.73333,159.31667 -76.73333,159.29167 -76.73333,159.26667 -76.73333,159.24167 -76.73333,159.21667 -76.73333,159.19167 -76.73333,159.16667 -76.73333,159.16667 -76.726664,159.16667 -76.719998,159.16667 -76.713332,159.16667 -76.706666,159.16667 -76.7,159.16667 -76.693334,159.16667 -76.686668,159.16667 -76.680002,159.16667 -76.673336,159.16667 -76.66667))", "dataset_titles": "Allan Hills Stable Water Isotopes; Exploring A 2 Million + Year Ice Climate Archive-Allan Hills Blue Ice Area (2MBIA)", "datasets": [{"dataset_uid": "609541", "doi": "10.7265/N5NP22DF", "keywords": "Allan Hills; Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Isotope", "people": "Spaulding, Nicole; Mayewski, Paul A.; Introne, Douglas; Kurbatov, Andrei V.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Allan Hills Stable Water Isotopes", "url": "https://www.usap-dc.org/view/dataset/609541"}, {"dataset_uid": "600099", "doi": "10.15784/600099", "keywords": "Allan Hills; Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Ice Core Records; Paleoclimate; Solid Earth", "people": "Bender, Michael", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Exploring A 2 Million + Year Ice Climate Archive-Allan Hills Blue Ice Area (2MBIA)", "url": "https://www.usap-dc.org/view/dataset/600099"}], "date_created": "Wed, 10 Dec 2014 00:00:00 GMT", "description": "This award supports a project to generate an absolute timescale for the Allan Hills Blue Ice Area (BIA), and then to reconstruct details of past climate changes and greenhouse gas concentrations for certain time periods back to 2.5 Ma. Ice ages will be determined by applying emerging methods for absolute and relative dating of trapped air bubbles (based on Argon-40/Argon-38, delta-18O of O2, and the O2/N2 ratio). To demonstrate the potential of the Allan Hills BIAs as a paleoclimate archive trenches and ice cores will be collected for age intervals corresponding to 110-140 ka, 1 Ma, and 2.5 Ma. During the proposed two field seasons a total of 6x100 m and additional 15 m cores will be combined with trenching. The intellectual merit of the proposed activity is that the results of this work will extend the landmark work of EPICA and other deep ice coring efforts, which give records dating back to 0.8 Ma, and will complement work planned by IPICS to drill a continuous Antarctic ice core extending to 1.5 Ma. The results will help to advance understanding of major climate regimes and transitions that took place between 0-2.5 Ma, including the 40 kyr world and the mid-Pleistocene climate transition. A major long-term scientific goal is to provide a transformative approach to the collection of paleoclimate records by establishing an \"International Climate Park\" in the Allan Hills BIA that would enable sampling of large quantities of known age ice as old as 2.5 Ma, by any interested American or foreign investigator. The broader impacts resulting from the proposed activity include training students who are well versed in advanced field, laboratory and numerical modeling methods combining geochemistry, glaciology, and paleoclimatology. We will include material relevant to our proposed research in our ongoing efforts in local education and in our outreach efforts for media. The University of Maine already has cyberinfrastructure, using state of the art web-based technology, which can provide a wide community of scientists with fast access to the results of our research. The work will contribute to the broad array of climate change studies that is informing worldwide understanding of natural and anthropogenic forced climate change, and the options for responding. This award has field work in Antarctica.", "east": 159.41667, "geometry": "POINT(159.29167 -76.7)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "GROUND-BASED OBSERVATIONS; LABORATORY; Deuterium Isotopes; Not provided; Oxygen Isotope", "locations": null, "north": -76.66667, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Spaulding, Nicole; Introne, Douglas; Bender, Michael; Kurbatov, Andrei V.; Mayewski, Paul A.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.73333, "title": "Collaborative Research: Exploring A 2 Million + Year Ice Climate Archive-Allan Hills Blue Ice Area (2MBIA)", "uid": "p0000046", "west": 159.16667}, {"awards": "0537661 Cuffey, Kurt; 0537593 White, James; 0537930 Steig, Eric", "bounds_geometry": "POINT(-112.08 -79.47)", "dataset_titles": "Stable Isotope Lab at INSTAAR, University of Colorado; WAIS ice core isotope data #342, 347, 348, 349, 350, 351 (full data link not provided)", "datasets": [{"dataset_uid": "000140", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "WAIS ice core isotope data #342, 347, 348, 349, 350, 351 (full data link not provided)", "url": "http://www.waisdivide.unh.edu/"}, {"dataset_uid": "002561", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Stable Isotope Lab at INSTAAR, University of Colorado", "url": "http://instaar.colorado.edu/sil/about/index.php"}], "date_created": "Mon, 09 Apr 2012 00:00:00 GMT", "description": "This award supports analyses of stable isotopes of water, dD, d18O and deuterium excess in the proposed West Antarctic Ice Sheet Divide (WAIS) deep ice core. The project will produce a continuous and high-resolution reconstruction of stable isotope ratios for the new core. dD and d18O values provide estimates of temperature change at the ice core site. Deuterium excess provides estimates of ocean surface conditions, such as sea surface temperature, at the moisture source areas. This new ice core is ideally situated to address questions ranging from ice sheet stability to abrupt climate change. WAIS Divide has high enough snowfall rates to record climate changes on annual to decadal time scales. It should also have ice old enough to capture the last interglacial period in detail. The West Antarctic ice sheet is the subject of great scrutiny as our modern climate warms and sea level rises. What are the prospects for added sea level rise from ice released by this ice sheet? Understanding how this ice sheet has responded to climate change in the past, which the data collected in this project will help to assess, is critical to answering this question. The high temporal resolution available in the WAIS Divide core will provide the best available basis for inter-comparison of millennial-scale climate changes between the poles, and thus a better understanding of the spatial expression and dynamics of rapid climate change events. Finally, the location of this core in the Pacific sector of West Antarctica makes it well situated for examining the influence of the tropical Pacific on Antarctica climate, on longer timescales than are available from the instrumental climate record. Analyses will include the measurement of sub-annually resolved isotope variations in the uppermost parts of the core, measurements at annual resolution throughout the last 10,000 years and during periods of rapid climate change prior to that, and measurements at 50-year resolution throughout the entire length of the core that is collected and processed during the period of this grant. We anticipate that this will be about half of the full core expected to be drilled. In terms of broader impacts, the PIs will share the advising of two graduate students, who will make this ice core the focus of their thesis projects. It will be done in an innovative multi-campus approach designed to foster a broader educational experience. As noted above, the data and interpretations generated by this proposal will address climate change questions not only of direct and immediate scientific interest, but also of direct and immediate policy interest.", "east": -112.08, "geometry": "POINT(-112.08 -79.47)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES", "is_usap_dc": true, "keywords": "West Antarctic Ice Sheet Divide; Not provided; Ice Core; WAIS Divide; LABORATORY; FIELD SURVEYS; Isotope; FIELD INVESTIGATION; Antarctica; West Antarctica; Stable Isotope Ratios; Antarctic; Ice Sheet; Deuterium", "locations": "WAIS Divide; West Antarctica; Antarctic; Antarctica; West Antarctic Ice Sheet Divide", "north": -79.47, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "White, James; Steig, Eric J.; Cuffey, Kurt M.; Souney, Joseph Jr.; Vaughn, Bruce", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "Project website", "repositories": "Project website", "science_programs": null, "south": -79.47, "title": "Collaborative Research: Stable Isotopes of Ice in the WAIS Divide Deep Ice Core", "uid": "p0000294", "west": -112.08}, {"awards": "0739598 Aydin, Murat; 0739491 Sowers, Todd", "bounds_geometry": null, "dataset_titles": "Alkanes in Firn Air Samples, Antarctica and Greenland; Methane Isotopes in South Pole Firn Air, 2008", "datasets": [{"dataset_uid": "609504", "doi": "10.7265/N5X9287C", "keywords": "Antarctica; Arctic; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Greenland; Snow/ice; Snow/Ice; South Pole; WAIS Divide", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": null, "title": "Alkanes in Firn Air Samples, Antarctica and Greenland", "url": "https://www.usap-dc.org/view/dataset/609504"}, {"dataset_uid": "609502", "doi": "10.7265/N55T3HFP", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Isotope; Paleoclimate; Snow/ice; Snow/Ice; South Pole", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": null, "title": "Methane Isotopes in South Pole Firn Air, 2008", "url": "https://www.usap-dc.org/view/dataset/609502"}], "date_created": "Thu, 18 Aug 2011 00:00:00 GMT", "description": "This award supports a project to make measurements of methane and other trace gases in firn air collected at South Pole, Antarctica. The analyses will include: methane isotopes (delta-13CH4 and delta-DCH4), light non-methane hydrocarbons (ethane, propane, and n-butane), sulfur gases (COS, CS2), and methyl halides (CH3Cl and CH3Br). The atmospheric burdens of these trace gases reflect changes in atmospheric OH, biomass burning, biogenic activity in terrestrial, oceanic, and wetland ecosystems, and industrial/agricultural activity. The goal of this project is to develop atmospheric histories for these trace gases over the last century through examination of depth profiles of these gases in South Pole firn air. The project will involve two phases: 1) a field campaign at South Pole, Antarctica to drill two firn holes and fill a total of ~200 flasks from depths reaching 120 m, 2) analysis of firn air at University of California, Irvine, Penn State University, and several other collaborating laboratories. Atmospheric histories will be inferred from the measurements using a one dimensional advective/diffusive model of firn air transport. This study will provide new information about the recent changes in atmospheric levels of these gases, providing about a 90 year long time series record that connects the earlier surface and firn air measurements to present day. The project will also explore the possibility of in- situ production of light non-methane hydrocarbons in firn air that is relevant to the interpretation of ice core records. The broader impacts of this research are that it has the potential for significant societal impact by improving our understanding of climate change and man\u0027s input to the atmosphere. The results of this work will be disseminated through the peer review process, and will contribute to environmental assessments, such as the Inter-governmental Panel on Climate Change (IPCC) Climate Assessment and the Word Meteorological Organization (WMO) Stratospheric Ozone Assessment. This research will provide educational opportunities for graduate and undergraduate students, and will contribute to a teacher training program for K-12 teachers in minority school districts.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GC-MS", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; Isotope; Firn Air Chemistry; Firn Air Isotope Measurements; Not provided; LABORATORY; South Pole; Firn; Delta 13C; Carbon-13; Mass Spectrometer; Deuterium; Mass Spectrometry; Firn Air Samples; Carbon; Gas Chromatography; Polar Firn Air; GROUND-BASED OBSERVATIONS; Methane; Antarctica; Firn Air Isotopes; Delta Deuterium; FIELD SURVEYS; Firn Air; Chromatography; Methane Isotopes; Carbon Isotopes; Stable Isotopes", "locations": "Antarctica; South Pole", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Aydin, Murat; Saltzman, Eric; Sowers, Todd A.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Methane Isotopes, Hydrocarbons, and other Trace Gases in South Pole Firn Air", "uid": "p0000162", "west": null}, {"awards": "0538657 Severinghaus, Jeffrey", "bounds_geometry": null, "dataset_titles": "Borehole Temperature Measurement in WDC05A in January 2008 and January 2009; d15N and d18O of air in the WAIS Divide ice core; Low-res d15N and d18O of O2 in the WAIS Divide 06A Deep Core; Ultra-High Resolution LA-ICP-MS Results: DO-21 Rapid Warming Event; WAIS Divide d18Oatm and Siple Dome/WAIS Divide composite and individual delta epsilon LAND", "datasets": [{"dataset_uid": "609637", "doi": "10.7265/N5B27S7S", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Temperature; WAIS Divide; WAIS Divide Ice Core", "people": "Severinghaus, Jeffrey P.; Orsi, Anais J.", "repository": "USAP-DC", "science_program": null, "title": "Borehole Temperature Measurement in WDC05A in January 2008 and January 2009", "url": "https://www.usap-dc.org/view/dataset/609637"}, {"dataset_uid": "601747", "doi": "10.15784/601747", "keywords": "Antarctica; Delta 15N; Delta 18O; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Gas Records; Ice Core Records; Isotope; Nitrogen; Nitrogen Isotopes; Oxygen; Oxygen Isotope; Snow/ice; Snow/Ice; WAIS; WAIS Divide", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "d15N and d18O of air in the WAIS Divide ice core", "url": "https://www.usap-dc.org/view/dataset/601747"}, {"dataset_uid": "609660", "doi": "10.7265/N5S46PWD", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Low-res d15N and d18O of O2 in the WAIS Divide 06A Deep Core", "url": "https://www.usap-dc.org/view/dataset/609660"}, {"dataset_uid": "601041", "doi": "10.15784/601041", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Gas; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; WAIS Divide Ice Core", "people": "Severinghaus, Jeffrey P.; Seltzer, Alan", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide d18Oatm and Siple Dome/WAIS Divide composite and individual delta epsilon LAND", "url": "https://www.usap-dc.org/view/dataset/601041"}, {"dataset_uid": "609635", "doi": "10.7265/N51J97PS", "keywords": "Arctic; Geochemistry; GISP; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate", "people": "Haines, Skylar; Kurbatov, Andrei V.; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": null, "title": "Ultra-High Resolution LA-ICP-MS Results: DO-21 Rapid Warming Event", "url": "https://www.usap-dc.org/view/dataset/609635"}], "date_created": "Thu, 08 Jul 2010 00:00:00 GMT", "description": "0538657\u003cbr/\u003eSeveringhaus\u003cbr/\u003eThis award supports a project to develop high-resolution (20-yr) nitrogen and oxygen isotope records on trapped gases in the WAIS Divide ice core (Antarctica), with a comparison record for chronological purposes in the GISP2 (Greenland) ice core. The main scientific objective is to provide an independent temperature-change record for the past 100,000 years in West Antarctica that is not subject to the uncertainty inherent in ice isotopes (18O and deuterium), the classical paleothermometer. Nitrogen isotopes (Delta 15N) in air bubbles in glacial ice record rapid surface temperature change because of thermal fractionation of air in the porous firn layer, and this isotopic anomaly is recorded in bubbles as the firn becomes ice. Using this gas-based temperature-change record, in combination with methane data as interpolar stratigraphic markers, the proposed work will define the precise relative timing of abrupt warming in Greenland and abrupt cooling at the WAIS Divide site during the millennial-scale climatic oscillations of Marine Isotopic Stage 3 (30-70 kyr BP) and the last glacial termination. The nitrogen isotope record also provides constraints on past firn thickness, which inform temperature and accumulation rate histories from the ice core. A search for possible solar-related cycles will be conducted with the WAIS Divide Holocene (Delta 15N.) Oxygen isotopes of O2 (Delta 18Oatm) are obtained as a byproduct of the (Delta 15N) measurement. The gas-isotopic records will enhance the value of other atmospheric gas measurements in WAIS Divide, which are expected to be of unprecedented quality. The high-resolution (Delta 18Oatm) records will provide chronological control for use by the international ice coring community and for surface glacier ice dating. Education of a graduate student, and training of a staff member in the laboratory, will contribute to the nation\u0027s human resource base. Outreach activities in the context of the International Polar Year will be enhanced. International collaboration is planned with the laboratory of LSCE, University of Paris.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e LA-ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Borehole Temperature; LABORATORY; Depth; Not provided; GROUND-BASED OBSERVATIONS; Wais Divide-project; Ice Core; WAIS Divide", "locations": "WAIS Divide", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Haines, Skylar; Mayewski, Paul A.; Orsi, Anais J.; Kurbatov, Andrei V.; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": null, "title": "Nitrogen and Oxygen Gas Isotopes in the WAIS Divide Ice Core as Constraints on Chronology, Temperature, and Accumulation Rate", "uid": "p0000036", "west": null}, {"awards": "0837988 Steig, Eric", "bounds_geometry": "POLYGON((-180 -65,-144 -65,-108 -65,-72 -65,-36 -65,0 -65,36 -65,72 -65,108 -65,144 -65,180 -65,180 -67.5,180 -70,180 -72.5,180 -75,180 -77.5,180 -80,180 -82.5,180 -85,180 -87.5,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.5,-180 -85,-180 -82.5,-180 -80,-180 -77.5,-180 -75,-180 -72.5,-180 -70,-180 -67.5,-180 -65))", "dataset_titles": "West Antarctica Ice Core and Climate Model Data", "datasets": [{"dataset_uid": "609536", "doi": "10.7265/N5QJ7F8B", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; WAIS Divide", "people": "Steig, Eric J.", "repository": "USAP-DC", "science_program": null, "title": "West Antarctica Ice Core and Climate Model Data", "url": "https://www.usap-dc.org/view/dataset/609536"}], "date_created": "Fri, 30 Apr 2010 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). \u003cbr/\u003e\u003cbr/\u003eThis award supports a project to reconstruct the past physical and chemical climate of Antarctica, with an emphasis on the region surrounding the Ross Sea Embayment, using \u003e60 ice cores collected in this region by US ITASE and by Australian, Brazilian, Chilean, and New Zealand ITASE teams. The ice core records are annually resolved and exceptionally well dated, and will provide, through the analyses of stable isotopes, major soluble ions and for some trace elements, instrumentally calibrated proxies for past temperature, precipitation, atmospheric circulation, chemistry of the atmosphere, sea ice extent, and volcanic activity. These records will be used to understand the role of solar, volcanic, and human forcing on Antarctic climate and to investigate the character of recent abrupt climate change over Antarctica in the context of broader Southern Hemisphere and global climate variability. The intellectual merit of the project is that ITASE has resulted in an array of ice core records, increasing the spatial resolution of observations of recent Antarctic climate variability by more than an order of magnitude and provides the basis for assessment of past and current change and establishes a framework for monitoring of future climate change in the Southern Hemisphere. This comes at a critical time as global record warming and other impacts are noted in the Southern Ocean, the Antarctic Peninsula, and on the Antarctic ice sheet. The broader impacts of the project are that Post-doctoral and graduate students involved in the project will benefit from exposure to observational and modeling approaches to climate change research and working meetings to be held at the two collaborating institutions plus other prominent climate change institutions. The results are of prime interest to the public and the media Websites hosted by the two collaborating institutions contain climate change position papers, scientific exchanges concerning current climate change issues, and scientific contribution series.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Deuterium Isotopes; Deuterium Excess; Not provided; GROUND-BASED OBSERVATIONS; Wais Divide-project", "locations": null, "north": -65.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Antarctic Climate Reconstruction Utilizing the US ITASE Ice Core Array (2009- 2012)", "uid": "p0000180", "west": -180.0}, {"awards": "0196105 Steig, Eric", "bounds_geometry": null, "dataset_titles": "US ITASE Stable Isotope Data, Antarctica", "datasets": [{"dataset_uid": "609425", "doi": "10.7265/N5NZ85MD", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Isotope; ITASE; Paleoclimate; WAIS", "people": "Steig, Eric J.", "repository": "USAP-DC", "science_program": "ITASE", "title": "US ITASE Stable Isotope Data, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609425"}], "date_created": "Thu, 01 Oct 2009 00:00:00 GMT", "description": "Not Available", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e AMS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e LIDAR/LASER SPECTROMETERS \u003e PALMS", "is_usap_dc": true, "keywords": "Isotope; Depth; Ice Core Gas Records; Ice Core; Ice Core Data; Ice Core Chemistry; LABORATORY; Firn Isotopes; FIELD SURVEYS; Deuterium; Ice Age; Oxygen Isotope; Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ITASE", "south": null, "title": "Stable Isotope Studies at West Antarctic ITASE Sites", "uid": "p0000013", "west": null}, {"awards": "0125579 Cuffey, Kurt; 0126202 Blankenship, Donald", "bounds_geometry": "POLYGON((160 -77.6,160.25 -77.6,160.5 -77.6,160.75 -77.6,161 -77.6,161.25 -77.6,161.5 -77.6,161.75 -77.6,162 -77.6,162.25 -77.6,162.5 -77.6,162.5 -77.63,162.5 -77.66,162.5 -77.69,162.5 -77.72,162.5 -77.75,162.5 -77.78,162.5 -77.81,162.5 -77.84,162.5 -77.87,162.5 -77.9,162.25 -77.9,162 -77.9,161.75 -77.9,161.5 -77.9,161.25 -77.9,161 -77.9,160.75 -77.9,160.5 -77.9,160.25 -77.9,160 -77.9,160 -77.87,160 -77.84,160 -77.81,160 -77.78,160 -77.75,160 -77.72,160 -77.69,160 -77.66,160 -77.63,160 -77.6))", "dataset_titles": "Ablation Rates of Taylor Glacier, Antarctica; Stable Isotopes of Ice on the Surface of Taylor Glacier, Antarctica; Surface Velocities of Taylor Glacier, Antarctica", "datasets": [{"dataset_uid": "609324", "doi": "10.7265/N5RV0KM7", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Velocity; Taylor Glacier", "people": "Cuffey, Kurt M.; Aciego, Sarah; Kavanaugh, Jeffrey; Bliss, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Surface Velocities of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609324"}, {"dataset_uid": "609326", "doi": "10.7265/N5N29TW8", "keywords": "Ablation Poles; Ablation Rates; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Taylor Glacier", "people": "Bliss, Andrew; Kavanaugh, Jeffrey; Cuffey, Kurt M.", "repository": "USAP-DC", "science_program": null, "title": "Ablation Rates of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609326"}, {"dataset_uid": "609323", "doi": "10.7265/N5WM1BBZ", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Isotope; Taylor Glacier", "people": "Bliss, Andrew; Cuffey, Kurt M.; Kavanaugh, Jeffrey; Aciego, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Stable Isotopes of Ice on the Surface of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609323"}], "date_created": "Tue, 13 Feb 2007 00:00:00 GMT", "description": "This award supports a project to significantly improve our understanding of how Taylor Glacier flows and responds to climate changes. Taylor Glacier drains the Taylor Dome region of the East Antarctic Ice Sheet and terminates in Taylor Valley, one of the Dry Valleys of Victoria Land. It provides a crucial and unique link between two intensively studied Antarctic environments: the Taylor Dome, from which a 130 kyr ice core paleoclimate record has recently been extracted, and the Dry Valleys, a pivotal Long-Term Ecological Research (LTER) site and a focus of research on geomorphology and glacial geology. The proposed work will thus make an important contribution to ongoing efforts to exploit the Taylor Dome - Dry Valleys system to build a uniquely comprehensive view of regional long-term environmental changes. The proposed work has two complementary components: field research and numerical modelling. Two field seasons will be used to measure velocity, surface strain rate, mass balance, ice thickness, glacier bed reflectance, and subglacial topography, along a nearly complete longitudinal transect of the Taylor Glacier, and along select cross-valley transects. This information will be used to constrain numerical models of ice and heat flow for the Taylor Dome - Taylor Glacier system. These calibrated models will be used to analyze the time-dependent response of the Taylor Glacier to climate changes. The synthesis of results will be aimed to improve understanding of the glacial geomorphology of Taylor Valley, and to illuminate impacts on the Taylor Valley lakes ecosystem. The project will have a major role in furthering the careers of a doctoral-level graduate student and a post-doctoral researcher.", "east": 162.5, "geometry": "POINT(161.25 -77.75)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Glacier; Glacier Surface; Glacier Surface Ablation; Ice Velocity; Velocity Measurements; Taylor Glacier; Isotope; GPS; Ice Sheet Elevation; Not provided; FIELD INVESTIGATION; Ice Surface Elevation; Ablation; Oxygen Isotope; Elevation; Deuterium; GROUND-BASED OBSERVATIONS; Glacier Surface Ablation Rate; Surface Elevation", "locations": "Taylor Glacier", "north": -77.6, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Bliss, Andrew; Kavanaugh, Jeffrey; Aciego, Sarah; Cuffey, Kurt M.; Morse, David L.; Blankenship, Donald D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.9, "title": "Collaborative Research: Dynamics and Climatic Response of the Taylor Glacier System", "uid": "p0000084", "west": 160.0}, {"awards": "0230452 Severinghaus, Jeffrey", "bounds_geometry": "POINT(124.5 -80.78)", "dataset_titles": "Antarctic megadunes", "datasets": [{"dataset_uid": "000191", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "Antarctic megadunes", "url": "http://nsidc.org/antarctica/megadunes/"}], "date_created": "Wed, 27 Sep 2006 00:00:00 GMT", "description": "This award supports a study of the chemical composition of air in the snow layer (firn) in a region of \"megadunes\" near Vostok station, Antarctica. It will test the hypothesis that a deep \"convective zone\" of vigorous wind-driven mixing can prevent gas fractionation in the upper one-third of the polar firn layer. In the megadunes, ultralow snow accumulation rates lead to structural changes (large grains, pipes, and cracks) that make the permeability of firn to air movement orders of magnitude higher than normal. The unknown thickness of the convective zone has hampered the interpretation of ice core 15N/14N and 40Ar/36Ar ratios as indicators of past firn thickness, which is a key constraint on the climatically important variables of temperature, accumulation rate, and gas age-ice age difference. Studying this \"extreme end-member\" example will better define the role of the convective zone in gas reconstructions. This study will pump air from a profile of ~20 depths in the firn, to definitively test for the presence of a convective zone based on the fit of observed 15 N/14N and 40Ar/36Ar to a molecular- and eddy-diffusion model. Permeability measurements on the core and 2-D air flow modeling (in collaboration with M. Albert) will permit a more physically realistic interpretation of the isotope data and will relate mixing vigor to air velocities. A new proxy indicator of convective zone thickness will be tested on firn and ice core bubble air, based on the principle that isotopes of slow-diffusing heavy noble gases (Kr, Xe) should be more affected by convection than isotopes of fast-diffusing N2 . These tools will be applied to a test of the hypothesis that the megadunes and a deep convective zone existed at the Vostok site during glacial periods, which would explain the anomalously low 15N/14N and 40Ar/36Ar in the Vostok ice core glacial periods. The broader impacts of this work include 1) clarification of phase relationships of greenhouse gases and temperature in ice core records, with implications for understanding of past and future climates, 2) education of one graduate student, and 3) building of collaborative relationships with five investigators.", "east": 124.5, "geometry": "POINT(124.5 -80.78)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS", "is_usap_dc": false, "keywords": "Antarctica; Methane; Carbon-14; Permeability; CO2; Firn Core; FIELD SURVEYS; Deuterium Excess; GROUND-BASED OBSERVATIONS; LABORATORY; Isotope; Ice Core Density; Firn Air; Megadunes; Ice Core; Not provided; FIELD INVESTIGATION", "locations": "Antarctica", "north": -80.78, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bauer, Rob; Albert, Mary R.; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "NSIDC", "repositories": "NSIDC", "science_programs": null, "south": -80.78, "title": "How Thick Is the Convective Zone: A Study of Firn Air in the Megadunes Near Vostok, Antarctica", "uid": "p0000097", "west": 124.5}, {"awards": "0125900 Sowers, Todd", "bounds_geometry": "POINT(-148.8 -81.7)", "dataset_titles": null, "datasets": null, "date_created": "Thu, 26 May 2005 00:00:00 GMT", "description": "0125900\u003cbr/\u003eSowers\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to improve the understanding of the biogeochemical processes that control CH4 emissions. Records of the concentration of methane in trapped gases in ice tell us about changes in atmospheric loading through time. Such records do not, however, provide information on the individual sources or sinks. One way to refine our understanding of the cycling of bioactive trace gases like methane is to use stable isotope records of trapped gases in ice cores. This project will measure the Deuterium/Hydrogen (D/H) ratio of methane trapped in shallow/recent ice (covering the last ~ 200 years) at Siple Dome, Antarctica. The proposed work will complement current efforts to measure the carbon-13 isotope ratio of methane in ice cores and will provide fundamental information on the various sources and sinks of atmospheric methane over the last 200 years.", "east": -148.8, "geometry": "POINT(-148.8 -81.7)", "instruments": null, "is_usap_dc": false, "keywords": "Siple Dome; Not provided; Ch4; Methane; Antarctica; Ice Core", "locations": "Siple Dome; Antarctica", "north": -81.7, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Sowers, Todd A.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -81.7, "title": "Constructing the first D/H record of atmospheric methane covering the last two centuries.", "uid": "p0000754", "west": -148.8}, {"awards": "0125981 Sowers, Todd", "bounds_geometry": "POLYGON((-180 -62.83,-144 -62.83,-108 -62.83,-72 -62.83,-36 -62.83,0 -62.83,36 -62.83,72 -62.83,108 -62.83,144 -62.83,180 -62.83,180 -65.547,180 -68.264,180 -70.981,180 -73.698,180 -76.415,180 -79.132,180 -81.849,180 -84.566,180 -87.283,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.283,-180 -84.566,-180 -81.849,-180 -79.132,-180 -76.415,-180 -73.698,-180 -70.981,-180 -68.264,-180 -65.547,-180 -62.83))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 05 May 2005 00:00:00 GMT", "description": "0125981\u003cbr/\u003eSowers\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to construct an isotopic record of atmospheric methane and nitrous oxide over the last century from South Pole firn air. Over the last 150 years, atmospheric methane and nitrous oxide concentrations have risen in response to increased emissions from various anthropogenic activities. As this trend is liable to continue in the foreseeable future, it is important to understand the biogeochemical processes that contribute to the emissions of these two greenhouse gases. In this context, records of the variations in the atmospheric loading of trace gases found in ice cores and interstitial spaces in the snow near the surface of the ice sheet (firn air) provide fundamental boundary conditions for reconstructing historical emission records. One way to improve our understanding of the cycling of bioactive trace gases and their emission records is to use stable isotope tracers, which have been recorded in the ice cores and firn air. This project will develop records of carbon-13 and deuterium isotope ratios of methane, as well as the nitrogen-15, oxygen-18 and the isotopomer composition of nitrous oxide trapped in firn air samples collected in January 2001 at the South Pole. These measurements will allow isotopic records of these atmospheric gases to be reconstructed throughout the 20th century. Such records will help to establish the relative contribution of individual sources with a higher degree of confidence than is currently available.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -62.83, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Sowers, Todd A.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -90.0, "title": "Generating an Isotopic Record of Atmospheric Methane and Nitrous Oxide Over the Last Century from South Pole Firn Air", "uid": "p0000086", "west": -180.0}, {"awards": "XXXXXXX Palais, Julie", "bounds_geometry": null, "dataset_titles": "Talos Dome Ice Core Deuterium Isotope Data", "datasets": [{"dataset_uid": "609252", "doi": "", "repository": "USAP-DC", "science_program": null, "title": "Talos Dome Ice Core Deuterium Isotope Data", "url": "http://www.usap-dc.org/view/dataset/609252"}], "date_created": "Fri, 27 Aug 2004 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; Talos Dome", "locations": "Talos Dome; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Stenni, Barbara; Jouzel, Jean", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "9526979 White, James", "bounds_geometry": null, "dataset_titles": "Siple Dome Core Date from Measurement of the d18O of Paleoatmospheric Oxygen", "datasets": [{"dataset_uid": "609123", "doi": "10.7265/N5TX3C95", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Bender, Michael; White, James", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Core Date from Measurement of the d18O of Paleoatmospheric Oxygen", "url": "https://www.usap-dc.org/view/dataset/609123"}], "date_created": "Mon, 16 Jun 2003 00:00:00 GMT", "description": "This award is for support for a program to measure the stable isotope (deuterium to hydrogen and oxygen-18 to oxygen-16) concentrations of ice cores retrieved from Siple Dome as part of the West Antarctic ice sheet program. In addition, the deuterium excess of samples from the Taylor Dome ice core will be determined. This project will approach the question of rapid climate change using ice cores to determine the history of temperature changes, moisture source changes, and elevational changes in the West Antarctic ice sheet. Results from ice cores taken to date in the interior of Antarctica (East and West) are surprisingly lacking in indications of abrupt climate changes, such as those that have been observed in the GISP2 ice core from Summit, Greenland. This work will address the question of whether rapid climate changes, which are known to have occurred in other parts of the southern hemi-sphere, may have also occurred in the coastal regions of West Antarctica. There is some indication from existing records of isotopes in ice cores that the West Antarctic ice sheet may have flushed ice in the past (as evidenced by large changes in elevation of the ice sheet).", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Antarctica; LABORATORY; WAISCORES; GROUND STATIONS; Siple Coast; Glaciology; Snow; D18O; Isotope; Thermometry; Ice Sheet; Siple; Accumulation; Ice Core; Siple Dome; Stratigraphy; Densification; GROUND-BASED OBSERVATIONS; Not provided", "locations": "Antarctica; Siple; Siple Coast; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "White, James; Bender, Michael", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Isotopic Measurements on the WAIS/Siple Dome Ice Cores", "uid": "p0000063", "west": null}, {"awards": "9615292 Wahlen, Martin", "bounds_geometry": null, "dataset_titles": "Carbon-Isotopic Composition of Atmospheric CO2 since the Last Glacial Maximum; Taylor Dome Ice Core Chemistry, Ion, and Isotope Data", "datasets": [{"dataset_uid": "609108", "doi": "10.7265/N54F1NN5", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "people": "Wahlen, Martin", "repository": "USAP-DC", "science_program": null, "title": "Carbon-Isotopic Composition of Atmospheric CO2 since the Last Glacial Maximum", "url": "https://www.usap-dc.org/view/dataset/609108"}, {"dataset_uid": "609246", "doi": "", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "people": "Indermuhle, A.; Steig, Eric J.; Sowers, Todd A.; Smith, Jesse; Brook, Edward J.; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Taylor Dome Ice Core Chemistry, Ion, and Isotope Data", "url": "https://www.usap-dc.org/view/dataset/609246"}], "date_created": "Tue, 01 Jan 2002 00:00:00 GMT", "description": "This award is for support of a program to reconstruct the record of atmospheric carbon dioxide (and the carbon-13 isotopes of carbon dioxide) over several intervals, including the Last Glacial Maximum-Holocene transition, interstadial episodes, the mid-Holocene, the last 1000 years and the penultimate glacial period, using ice from the Taylor Dome and Vostok ice cores. The major objective of this study is to investigate the phase relationship between variations of the greenhouse gases occluded in the ice cores and temperature changes (indicated by oxygen and deuterium isotopes) during the last deglaciation. In addition, the concentration of atmospheric carbon dioxide over the past 1000 years and during the mid-Holocene will be determined in these cores.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "USAP-DC; Ice Core; GROUND-BASED OBSERVATIONS; Carbon; Trapped Gases; Glaciology; GROUND STATIONS; Taylor Dome; Carbon Dioxide; Isotope; Antarctica; Nitrogen", "locations": "Antarctica; Taylor Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.; Wahlen, Martin; Smith, Jesse; Brook, Edward J.; Indermuhle, A.; Mayewski, Paul A.; Sowers, Todd A.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": null, "title": "Carbon Dioxide and Carbon Isotopes in the Taylor Dome and Vostok Ice Cores", "uid": "p0000153", "west": null}]

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