USAP-DC

{"dp_type": "Project", "free_text": "Firn Isotopes"}

[{"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": "0440975 Severinghaus, Jeffrey", "bounds_geometry": "POINT(-119.533333 -80.016667)", "dataset_titles": "Nitrogen and Oxygen Gas Isotopes in the Siple Dome and Byrd Ice Cores, Antarctica", "datasets": [{"dataset_uid": "609407", "doi": "10.7265/N55X26V0", "keywords": "Antarctica; Arctic; Atmosphere; Byrd Glacier; Byrd Ice Core; Chemistry:fluid; Chemistry:Fluid; Geochemistry; GISP2; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Nitrogen and Oxygen Gas Isotopes in the Siple Dome and Byrd Ice Cores, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609407"}], "date_created": "Fri, 17 Jul 2009 00:00:00 GMT", "description": "The award supports the development of high-resolution nitrogen and oxygen isotope records on trapped gases in the Byrd and Siple Dome ice cores, and the Holocene part of the GISP2 ice core. The primary scientific goals of this work are to understand the enigmatic d15N anomalies seen thus far in the Siple Dome record at 15.3 ka and 35 ka, and to find other events that may occur in both cores. At these events, d15N of trapped air approaches zero, implying little or no gravitational fractionation of gases in the firn layer at the time of formation of the ice. These events may represent times of low accumulation rate and arid meteorological conditions, and thus may contain valuable information about the climatic history of West Antarctica. Alternatively, they may stem from crevassing and thus may reveal ice-dynamical processes. Finding the events in the Byrd core, which is located 500 km from Siple Dome, would place powerful constraints on their origin and significance. A second major goal is to explore the puzzling absence of the abrupt warming event at 22 ka (seen at Siple Dome) in the nearby Byrd 18O/16O record in the ice (d18Oice), and search for a possible correlative signal in Byrd d15N. A third goal takes advantage of the fact that precise measurements of the oxygen isotopic composition of atmospheric O2 (d18Oatm) are obtained as a byproduct of the d15N measurement. The proposed gas-isotopic measurements will underpin an integrated suite of West Antarctic climate and atmospheric gas records, which will ultimately include the WAIS Divide core. These records will help separate regional from global climate signals, and may place constraints on the cause of abrupt climate change. Education of two graduate students, and training of two staff members in the laboratory, contribute to the nation\u0027s human resource base. Education and outreach will be an important component of the project.", "east": -119.533333, "geometry": "POINT(-119.533333 -80.016667)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Antarctica; Firn Air Isotopes; Not provided; Nitrogen Isotopes; LABORATORY; Firn Isotopes; Paleoclimate; FIELD SURVEYS; Ice Core; Oxygen Isotope; FIELD INVESTIGATION; Siple Dome", "locations": "Antarctica; Siple Dome", "north": -80.016667, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; 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": "Siple Dome Ice Core", "south": -80.016667, "title": "Nitrogen and oxygen gas isotopes in the Siple Dome and Byrd ice cores", "uid": "p0000450", "west": -119.533333}, {"awards": "0440759 Sowers, Todd; 0440602 Saltzman, Eric; 0440701 Severinghaus, Jeffrey; 0440509 Battle, Mark; 0440498 White, James; 0440615 Brook, Edward J.", "bounds_geometry": "POINT(-112.085 -79.467)", "dataset_titles": "Gases in Firn Air and Shallow Ice at the WAIS Drilling Site, Antarctica; Ice Core Air Carbonyl Sulfide Measurements - SPRESSO Ice Core; Methane Isotopes from the WAIS Divide Ice Core; Surface Temperature Reconstruction from Borehole Temperature Measurement in WDC05A; WAIS ice core Methane Data, Carbon Dioxide Data", "datasets": [{"dataset_uid": "609638", "doi": "10.7265/N56971HF", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Temperature; WAIS Divide; WAIS Divide Ice Core", "people": "Orsi, Anais J.; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Surface Temperature Reconstruction from Borehole Temperature Measurement in WDC05A", "url": "https://www.usap-dc.org/view/dataset/609638"}, {"dataset_uid": "609412", "doi": "10.7265/N5251G40", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Snow/ice; Snow/Ice; WAIS Divide; WAIS Divide Ice Core", "people": "Saltzman, Eric", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Gases in Firn Air and Shallow Ice at the WAIS Drilling Site, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609412"}, {"dataset_uid": "609435", "doi": "10.7265/N5J67DW0", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Isotope; Methane; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Methane Isotopes from the WAIS Divide Ice Core", "url": "https://www.usap-dc.org/view/dataset/609435"}, {"dataset_uid": "609493", "doi": "10.7265/N5319SV3", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "people": "Mitchell, Logan E; McConnell, Joseph; Brook, Edward J.; Taylor, Kendrick C.; Sowers, Todd A.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS ice core Methane Data, Carbon Dioxide Data", "url": "https://www.usap-dc.org/view/dataset/609493"}, {"dataset_uid": "601357", "doi": "10.15784/601357", "keywords": "Antarctica; Atmospheric Gases; Gas Measurement; Ice Core; Ice Core Gas Records; Trace Gases", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": null, "title": "Ice Core Air Carbonyl Sulfide Measurements - SPRESSO Ice Core", "url": "https://www.usap-dc.org/view/dataset/601357"}], "date_created": "Tue, 03 Feb 2009 00:00:00 GMT", "description": "This award supports a project to measure the elemental and isotopic composition of firn air and occluded air in shallow boreholes and ice cores from the WAIS Divide site, the location of a deep ice-coring program planned for 2006-07 and subsequent seasons. The three primary objectives are: 1) to establish the nature of firn air movement and trapping at the site to aid interpretations of gas data from the deep core; 2) to expand the suite of atmospheric trace gas species that can be measured in ice and replicate existing records of other species; and 3) to inter-calibrate all collaborating labs to insure that compositional and isotopic data sets are inter-comparable. The program will be initiated with a shallow drilling program during the 05/06 field season which will recover two 300+m cores and firn air samples. The ice core and firn air will provide more than 700 years of atmospheric history that will be used to address a number of important questions related to atmospheric change over this time period. The research team consists of six US laboratories that also plan to participate in the deep core program. This collaborative research program has a number of advantages. First, the scientists will be able to coordinate sample allocation a priori to maximize the resolution and overlap of records of interrelated species. Second, sample registration will be exact, allowing direct comparison of all records. Third, a coherent data set will be produced at the same time and all PI.s will participate in interpreting and publishing the results. This will insure that the best possible understanding of gas records at the WAIS Divide site will be achieved, and that all work necessary to interpret the deep core is conducted in a timely fashion. The collaborative structure created by the proposal will encourage sharing of techniques, equipment, and ideas between the laboratories. The research will identify impacts of various industrial/agricultural activities and help to distinguish them from natural variations, and will include species for which there are no long records of anthropogenic impact. The work will also help to predict future atmospheric loadings. The project will contribute to training scientists at several levels, including seven undergraduates, two graduate students and one post doctoral fellow.", "east": -112.085, "geometry": "POINT(-112.085 -79.467)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GC-MS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e SPECTROMETERS \u003e SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS", "is_usap_dc": true, "keywords": "Ice Core Chemistry; WAIS Divide; Firn; LABORATORY; Ice Core; Firn Air Isotope Measurements; Shallow Firn Air; FIELD INVESTIGATION; Ice Core Gas Records; GROUND-BASED OBSERVATIONS; Firn Isotopes; Wais Divide-project; Gas Data; Polar Firn Air; Not provided; Trace Gas Species; Trapped Gases; West Antarctic Ice Sheet; Deep Core; Ice Sheet; Gas; Firn Air Isotopes; FIELD SURVEYS; Air Samples; Atmospheric Gases; Isotope; Cores; Atmosphere; Ice Core Data; Surface Temperatures; Firn Air; Borehole; Antarctica", "locations": "West Antarctic Ice Sheet; Antarctica; WAIS Divide", "north": -79.467, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Battle, Mark; Mischler, John; Saltzman, Eric; Aydin, Murat; White, James; Brook, Edward J.; Orsi, Anais J.; Severinghaus, Jeffrey P.; Sowers, Todd A.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.467, "title": "Collaborative Research: Gases in Firn Air and Shallow Ice at the Proposed WAIS Divide Drilling Site", "uid": "p0000368", "west": -112.085}, {"awards": "9526556 Sowers, Todd", "bounds_geometry": "POINT(-148.3023 -81.403)", "dataset_titles": "Carbon-13 Isotopic Composition of Atmospheric Methane in Firn Air, South Pole and Siple Dome, Antarctica", "datasets": [{"dataset_uid": "609310", "doi": "10.7265/N5ST7MR2", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Siple Dome; Snow/ice; Snow/Ice; South Pole", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Carbon-13 Isotopic Composition of Atmospheric Methane in Firn Air, South Pole and Siple Dome, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609310"}], "date_created": "Mon, 09 Jul 2007 00:00:00 GMT", "description": "This award is for support for a program to reconstruct records of the isotopic composition of paleoatmospheric methane and nitrous oxide covering the last 200,000 years. High resolution measurements of the carbon-13 isotopic composition of methane from shallow ice cores will help to determine the relative contributions of biogenic (wetlands, rice fields and ruminants) and abiogenic (biomass burning and natural gas) methane emissions which have caused the concentrations of this gas to increase at an exponential rate during the anthropogenic period. Isotopic data on methane and nitrous oxide over glacial/interglacial timescales will help determine the underlying cause of the large concentration variations that are known to occur. This project will make use of a new generation mass spectrometer which is capable of generating precise isotopic information on nanomolar quantities of methane and nitrous oxide, which means that samples can be 1000 times smaller than those needed for a standard isotope ratio instrument. The primary objective of the work is to further our understanding of the biogeochemical cycles of these two greenhouse gases throughout the anthropogenic period as well as over glacial interglacial timescales.", "east": -148.3023, "geometry": "POINT(-148.3023 -81.403)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Ice Core; Firn Air Isotope Measurements; Ice Core Chemistry; Firn Isotopes; Stable Isotopes; Methane; Carbon; Paleoclimate; LABORATORY; Siple Dome; Antarctica; Ice Core Data; Firn Air Isotopes; Antarctic Ice Sheet", "locations": "Antarctica; Antarctic Ice Sheet; Siple Dome", "north": -81.403, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Sowers, Todd A.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.403, "title": "Constructing Paleoatmospheric Records of the Isotopic Composition of Methane and Nitrous Oxide", "uid": "p0000611", "west": -148.3023}, {"awards": "0230260 Bender, Michael; 0230448 Severinghaus, Jeffrey", "bounds_geometry": "POLYGON((-75.34 86.6,-68.742 86.6,-62.144 86.6,-55.546 86.6,-48.948 86.6,-42.35 86.6,-35.752 86.6,-29.154 86.6,-22.556 86.6,-15.958 86.6,-9.36 86.6,-9.36 83.618,-9.36 80.636,-9.36 77.654,-9.36 74.672,-9.36 71.69,-9.36 68.708,-9.36 65.726,-9.36 62.744,-9.36 59.762,-9.36 56.78,-15.958 56.78,-22.556 56.78,-29.154 56.78,-35.752 56.78,-42.35 56.78,-48.948 56.78,-55.546 56.78,-62.144 56.78,-68.742 56.78,-75.34 56.78,-75.34 59.762,-75.34 62.744,-75.34 65.726,-75.34 68.708,-75.34 71.69,-75.34 74.672,-75.34 77.654,-75.34 80.636,-75.34 83.618,-75.34 86.6))", "dataset_titles": "Firn Air Inert Gas and Oxygen Observations from Siple Dome, 1996, and the South Pole, 2001; Trapped Gas Composition and Chronology of the Vostok Ice Core", "datasets": [{"dataset_uid": "609311", "doi": "10.7265/N5P26W12", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Lake Vostok; Paleoclimate; Vostok; Vostok Ice Core", "people": "Suwa, Makoto; Bender, Michael", "repository": "USAP-DC", "science_program": null, "title": "Trapped Gas Composition and Chronology of the Vostok Ice Core", "url": "https://www.usap-dc.org/view/dataset/609311"}, {"dataset_uid": "609290", "doi": "10.7265/N5FJ2DQC", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciology; Paleoclimate; Siple Dome; Snow/ice; Snow/Ice; South Pole", "people": "Bender, Michael; Severinghaus, Jeffrey P.; Battle, Mark", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Firn Air Inert Gas and Oxygen Observations from Siple Dome, 1996, and the South Pole, 2001", "url": "https://www.usap-dc.org/view/dataset/609290"}], "date_created": "Wed, 18 Jan 2006 00:00:00 GMT", "description": "High latitude deep ice cores contain fundamental records of polar temperatures, atmospheric dust loads (and continental aridity), greenhouse gas concentrations, the status of the biosphere, and other essential properties of past environments. An accurate chronology for these records is needed if their significance is to be fully realized. The dating challenge has stimulated efforts at orbital tuning. In this approach, one varies a timescale, within allowable limits, to optimize the match between a paleoenvironmental property and a curve of insolation through time. The ideal property would vary with time due to direct insolation forcing. It would be unaffected by complex climate feedbacks and teleconnections, and it would give a clean record with high signal/noise ratio. It is argued strongly that the O2/N2 ratio of ice core trapped gases is such a property, and evidence is presented that this property, whose atmospheric ratio is nearly constant, is tied to local summertime insolation. This award will support a project to analyze the O2/N2 ratios at 1 kyr intervals from ~ 115-400 ka in the Vostok ice core. Ancillary measurements will be made of Ar/N2, and Ne/N2 and heavy noble gas ratios, in order to understand bubble close-off fractionation and its manifestation in the Vostok trapped gas record. O2/N2 variations will be matched with summertime insolation at Vostok to achieve a high-accuracy chronology for the Vostok core. The Vostok and other correlatable climate records will then be reexamined to improve our understanding of the dynamics of Pleistocene climate change.", "east": 106.8, "geometry": "POINT(106.8 -72.4667)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Paleoclimate; Siple Dome; Ice Age; Shallow Firn Air; Firn Air Isotope Measurements; Polar Firn Air; Ice Sample Gas Integrity; Oxygen Isotope; Noble Gas; Ice Core Gas Records; Atmospheric Gases; Trapped Gases; Not provided; LABORATORY; Vostok; Firn Air Isotopes; Thermal Fractionation; Ice Core Chemistry; Trapped Air Bubbles; Ice Core; Antarctica; South Pole; Ice Core Data; GROUND-BASED OBSERVATIONS; Gas Age; Firn Isotopes", "locations": "Antarctica; Vostok; Siple Dome; South Pole", "north": -72.4667, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Battle, Mark; Bender, Michael; Suwa, Makoto; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -72.4667, "title": "Collaborative Research: Trapped Gas Composition and the Chronology of the Vostok Ice Core", "uid": "p0000257", "west": 106.8}, {"awards": "9725305 Severinghaus, Jeffrey", "bounds_geometry": null, "dataset_titles": "Firn Air Isotope and Temperature Measurements from Siple Dome and South Pole", "datasets": [{"dataset_uid": "609098", "doi": "10.7265/N51N7Z2P", "keywords": "Antarctica; Atmosphere; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciology; Isotope; Paleoclimate; Siple Dome; Snow/ice; Snow/Ice; South Pole; Temperature", "people": "Battle, Mark; Severinghaus, Jeffrey P.; Grachev, Alexi", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Firn Air Isotope and Temperature Measurements from Siple Dome and South Pole", "url": "https://www.usap-dc.org/view/dataset/609098"}], "date_created": "Mon, 01 Jan 2001 00:00:00 GMT", "description": "9725305 Severinghaus This award supports a project to develop and apply a new technique for quantifying temperature changes in the past based on the thermodynamic principle of thermal diffusion, in which gas mixtures in a temperature gradient become fractionated. Air in polar firn is fractionated by temperature gradients induced by abrupt climate change, and a record of this air is preserved in bubbles in the ice. The magnitude of the abrupt temperature change, the precise relative timing, and an estimate of the absolute temperature change can be determined. By providing a gas-phase stratigraphic marker of temperature change, the phasing of methane (with decadal precision) and hence widespread climate change (relative to local polar temperature changes) can be determined (across five abrupt warming events during the last glacial period).", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS", "is_usap_dc": true, "keywords": "Isotopic History; GROUND STATIONS; Thermal Diffusion; Firn Temperature Measurements; Not provided; Oxygen Isotope; Trapped Air Bubbles; Shallow Firn Air; Firn Air Isotope Measurements; Seasonal Temperature Gradients; Mass Spectrometry; GROUND-BASED OBSERVATIONS; Thermal Fractionation; Polar Firn Air; Isotopic Anomalies; Xenon; Atmospheric Gases; Argon Isotopes; Siple Dome; Krypton; Nitrogen Isotopes; Seasonal Temperature Changes; Antarctica; Ice Core Gas Records; Firn Air Isotopes; Mass Spectrometer; South Pole; Firn Isotopes; Borehole", "locations": "Antarctica; Siple Dome; South Pole", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Battle, Mark; Grachev, Alexi; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Thermal Fractionation of Firn Air and the Ice Core Record of Abrupt Interstadial Climate Change", "uid": "p0000160", "west": null}]

View results on map Help on results map