USAP-DC

{"dp_type": "Dataset", "free_text": "Greenhouse Gas"}

[{"awards": "1643716 Buizert, Christo", "bounds_geometry": ["POLYGON((-180 -67,-144 -67,-108 -67,-72 -67,-36 -67,0 -67,36 -67,72 -67,108 -67,144 -67,180 -67,180 -69.3,180 -71.6,180 -73.9,180 -76.2,180 -78.5,180 -80.8,180 -83.1,180 -85.4,180 -87.7,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.7,-180 -85.4,-180 -83.1,-180 -80.8,-180 -78.5,-180 -76.2,-180 -73.9,-180 -71.6,-180 -69.3,-180 -67))"], "date_created": "Mon, 22 May 2023 00:00:00 GMT", "description": "We have reconstructed the atmospheric N2O mole fraction and its isotopic composition by combining data from ice cores, firn air, and atmospheric samples. The mole fraction reconstruction extends back to 1000 CE using ice cores, firn air, and atmospheric sampling; and the isotopic reconstruction extends back to 1900 CE using only firn air data. We have incorporated both newly measured and previously published data. We present new data for the mole fraction, d15Nbulk, d18O, and d15NSP values from the Styx (East Antarctica) firn air, and mole fraction from the North Greenland Eemian Ice drilling Project (NEEM) firn air. We have used published records from the Styx and NEEM ice cores, direct atmospheric measurements from the NOAA global sampling network, and firn air data, giving a total of 11 sites for N2O mole fraction, 12 sites for d15Nbulk, 11 sites for d18O, and 8 sites for d15NSP values.\r\n", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctic; Antarctica; Anthropogenic Emission; Atmosphere; Greenhouse Gas; Greenland; Ice Core Data; Nitrification And Denitrification Processes; Nitrous Oxide; Site-Specific 15N Isotopomer; Styx Glacier", "locations": "Antarctic; Greenland; Antarctica; Styx Glacier", "north": -67.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Ghosh, Sambit; Toyoda, Sakae ; Buizert, Christo ; Langenfelds, Ray L ; Yoshida, Naohiro ; Joong Kim, Seong; Ahn, Jinho ; Etheridge, David", "project_titles": "Collaborative Research: Reconstructing Carbon-14 of Atmospheric Carbon Monoxide from Law Dome, Antarctica to Constrain Long-Term Hydroxyl Radical Variability", "projects": [{"proj_uid": "p0010341", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing Carbon-14 of Atmospheric Carbon Monoxide from Law Dome, Antarctica to Constrain Long-Term Hydroxyl Radical Variability"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Concentration and isotopic composition of atmospheric N2O over the last century", "uid": "601693", "west": -180.0}, {"awards": "1443263 Higgins, John; 1443276 Brook, Edward", "bounds_geometry": ["POLYGON((159 -75.67,159.025 -75.67,159.05 -75.67,159.075 -75.67,159.1 -75.67,159.125 -75.67,159.15 -75.67,159.175 -75.67,159.2 -75.67,159.225 -75.67,159.25 -75.67,159.25 -75.786,159.25 -75.902,159.25 -76.018,159.25 -76.134,159.25 -76.25,159.25 -76.366,159.25 -76.482,159.25 -76.598,159.25 -76.714,159.25 -76.83,159.225 -76.83,159.2 -76.83,159.175 -76.83,159.15 -76.83,159.125 -76.83,159.1 -76.83,159.075 -76.83,159.05 -76.83,159.025 -76.83,159 -76.83,159 -76.714,159 -76.598,159 -76.482,159 -76.366,159 -76.25,159 -76.134,159 -76.018,159 -75.902,159 -75.786,159 -75.67))"], "date_created": "Wed, 20 Jan 2021 00:00:00 GMT", "description": "This file includes the concentration of carbon dioxide (CO2) and methane (CH4) in the trapped air from the S27 ice core collected in Allan Hills Blue Ice Area.", "east": 159.25, "geometry": ["POINT(159.125 -76.25)"], "keywords": "Allan Hills; Antarctica; Blue Ice; Carbon Dioxide; Ice Core; Methane", "locations": "Allan Hills; Antarctica; Antarctica", "north": -75.67, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Yan, Yuzhen; Brook, Edward J.", "project_titles": "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", "projects": [{"proj_uid": "p0000760", "repository": "USAP-DC", "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"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.83, "title": "Greenhouse gas composition in the Allan Hills S27 ice core", "uid": "601425", "west": 159.0}, {"awards": "1443263 Higgins, John", "bounds_geometry": ["POINT(159.35507 -76.73286)"], "date_created": "Wed, 14 Aug 2019 00:00:00 GMT", "description": "This file includes the concentration methane (CH4) in Allan Hills ice cores (ALHIC1502 and ALHIC1503).", "east": 159.35507, "geometry": ["POINT(159.35507 -76.73286)"], "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", "locations": "Allan Hills; Antarctica", "north": -76.73286, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Yan, Yuzhen; Bender, Michael; Brook, Edward J.; Higgins, John", "project_titles": "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", "projects": [{"proj_uid": "p0000760", "repository": "USAP-DC", "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"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.73286, "title": "Methane concentration in Allan Hills ice cores", "uid": "601203", "west": 159.35507}, {"awards": "0944197 Waddington, Edwin", "bounds_geometry": ["POINT(-112.1115 -79.481)"], "date_created": "Tue, 28 Mar 2017 00:00:00 GMT", "description": "The West Antarctic Ice Sheet Divide (WAIS Divide, WD) ice core is a newly drilled, high-accumulation deep ice core that provides Antarctic climate records of the past ~68 ka at unprecedented temporal resolution. The upper 2850 m (back to 31.2 ka BP) have been dated using annual-layer counting. Here we present a chronology for the deep part of the core (67.8-31.2 ka BP), which is based on stratigraphic matching to annual-layer-counted Greenland ice cores using globally well-mixed atmospheric methane. We calculate the WD gas age-ice age difference (Delta age) using a combination of firn densification modeling, ice-flow modeling, and a data set of d15N-N2, a proxy for past firn column thickness. The largest Delta age at WD occurs during the Last Glacial Maximum, and is 525 +/- 120 years. Internally consistent solutions can be found only when assuming little to no influence of impurity content on densification rates, contrary to a recently proposed hypothesis. We synchronize the WD chronology to a linearly scaled version of the layer-counted Greenland Ice Core Chronology (GICC05), which brings the age of Dansgaard-Oeschger (DO) events into agreement with the U/Th absolutely dated Hulu Cave speleothem record. The small Delta age at WD provides valuable opportunities to investigate the timing of atmospheric greenhouse gas variations relative to Antarctic climate, as well as the interhemispheric phasing of the \\\"bipolar seesaw\\\".\n\nWe present the WD2014 chronology for the upper part (0-2850 m; 31.2 ka BP) of the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core. The chronology is based on counting of annual layers observed in the chemical, dust and electrical conductivity records. These layers are caused by seasonal changes in the source, transport, and deposition of aerosols. The measurements were interpreted manually and with the aid of two automated methods. We validated the chronology by comparing to two high-accuracy, absolutely dated chronologies. For the Holocene, the cosmogenic isotope records of 10Be from WAIS Divide and 14C for IntCal13 demonstrated that WD2014 was consistently accurate to better than 0.5% of the age. For the glacial period, comparisons to the Hulu Cave chronology demonstrated that WD2014 had an accuracy of better than 1% of the age at three abrupt climate change events between 27 and 31ka. WD2014 has consistently younger ages than Greenland ice core chronologies during most of the Holocene. For the Younger Dryas-Preboreal transition (11.595 ka; 24 years younger) and the Bolling-Allerod Warming (14.621 ka; 7 years younger), WD2014 ages are within the combined uncertainties of the timescales. Given its high accuracy, WD2014 can become a reference chronology for the Southern Hemisphere, with synchronization to other chronologies feasible using high-quality proxies of volcanism, solar activity, atmospheric mineral dust, and atmospheric methane concentrations.", "east": -112.1115, "geometry": ["POINT(-112.1115 -79.481)"], "keywords": "Antarctica; Depth-Age-Model; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.481, "nsf_funding_programs": null, "persons": "Fudge, T. J.", "project_titles": "Collaborative Research: Establishing the Chronology and Histories of Accumulation and Ice Dynamics for the WAIS Divide Core", "projects": [{"proj_uid": "p0000026", "repository": "USAP-DC", "title": "Collaborative Research: Establishing the Chronology and Histories of Accumulation and Ice Dynamics for the WAIS Divide Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "WD2014: Timescale for WAIS Divide Core 2006 A (WDC-06A)", "uid": "601015", "west": -112.1115}, {"awards": "1245821 Brook, Edward", "bounds_geometry": ["POINT(162.167 -77.733)"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This award supports a project to use the Taylor Glacier, Antarctica, ablation zone to collect ice samples for a range of paleoenvironmental studies. A record of carbon-14 of atmospheric methane (14CH4) will be obtained for the last deglaciation and the Early Holocene, together with a supporting record of CH4 stable isotopes. In-situ cosmogenic 14C content and partitioning of 14C between different species (14CH4, C-14 carbon monoxide (14CO) and C-14 carbon dioxide (14CO2)) will be determined with unprecedented precision in ice from the surface down to ~67 m. Further age-mapping of the ablating ice stratigraphy will take place using a combination of CH4, CO2, and delta 18O of oxygen gas and H2O stable isotopes. High precision, high-resolution records of CO2, delta 13C of CO2, nitrous oxide (N2O) and N2O isotopes will be obtained for the last deglaciation and intervals during the last glacial period. The potential of 14CO2 and Krypton-81 (81Kr) as absolute dating tools for glacial ice will be investigated. The intellectual merit of proposed work includes the fact that the response of natural methane sources to continuing global warming is uncertain, and available evidence is insufficient to rule out the possibility of catastrophic releases from large 14C-depleted reservoirs such as CH4 clathrates and permafrost. The proposed paleoatmospheric 14CH4 record will improve our understanding of the possible magnitude and timing of CH4 release from these reservoirs during a large climatic warming. A thorough understanding of in-situ cosmogenic 14C in glacial ice (production rates by different mechanisms and partitioning between species) is currently lacking. Such an understanding will likely enable the use of in-situ 14CO in ice at accumulation sites as a reliable, uncomplicated tracer of the past cosmic ray flux and possibly past solar activity, as well as the use of 14CO2 at both ice accumulation and ice ablation sites as an absolute dating tool. Significant gaps remain in our understanding of the natural carbon cycle, as well as in its responses to global climate change. The proposed high-resolution, high-precision records of delta 13C of CO2 would provide new information on carbon cycle changes both during times of rising CO2 in a warming climate and falling CO2 in a cooling climate. N2O is an important greenhouse gas that increased by ~30% during the last deglaciation. The causes of this increase are still largely uncertain, and the proposed high-precision record of N2O concentration and isotopes would provide further insights into N2O source changes in a warming world. The broader impacts of proposed work include an improvement in our understanding of the response of these greenhouse gas budgets to global warming and inform societally important model projections of future climate change. The continued age-mapping of Taylor Glacier ablation ice will add value to this high-quality, easily accessible archive of natural environmental variability. Establishing 14CO as a robust new tracer for past cosmic ray flux would inform paleoclimate studies and constitute a valuable contribution to the study of the societally important issue of climate change. The proposed work will contribute to the development of new laboratory and field analytical systems. The data from the study will be made available to the scientific community and the broad public through the NSIDC and NOAA Paleoclimatology data centers. 1 graduate student each will be trained at UR, OSU and SIO, and the work will contribute to the training of a postdoc at OSU. 3 UR undergraduates will be involved in fieldwork and research. The work will support a new, junior UR faculty member, Petrenko. All PIs have a strong history of and commitment to scientific outreach in the forms of media interviews, participation in filming of field projects, as well as speaking to schools and the public about their research, and will continue these activities as part of the proposed work. This award has field work in Antarctica.", "east": 162.167, "geometry": ["POINT(162.167 -77.733)"], "keywords": "Antarctica; Atmosphere; Geochemistry; Ice Core Records; Isotope; Paleoclimate; Taylor Glacier; Transantarctic Mountains", "locations": "Taylor Glacier; Transantarctic Mountains; Antarctica", "north": -77.733, "nsf_funding_programs": null, "persons": "Brook, Edward J.", "project_titles": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "projects": [{"proj_uid": "p0000283", "repository": "USAP-DC", "title": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.733, "title": "The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "uid": "600163", "west": 162.167}, {"awards": "0838849 Bender, Michael", "bounds_geometry": ["POLYGON((159.16667 -76.66667,159.19167 -76.66667,159.21667 -76.66667,159.24167 -76.66667,159.26667 -76.66667,159.29167 -76.66667,159.31667 -76.66667,159.34167 -76.66667,159.36667 -76.66667,159.39167 -76.66667,159.41667 -76.66667,159.41667 -76.673336,159.41667 -76.680002,159.41667 -76.686668,159.41667 -76.693334,159.41667 -76.7,159.41667 -76.706666,159.41667 -76.713332,159.41667 -76.719998,159.41667 -76.726664,159.41667 -76.73333,159.39167 -76.73333,159.36667 -76.73333,159.34167 -76.73333,159.31667 -76.73333,159.29167 -76.73333,159.26667 -76.73333,159.24167 -76.73333,159.21667 -76.73333,159.19167 -76.73333,159.16667 -76.73333,159.16667 -76.726664,159.16667 -76.719998,159.16667 -76.713332,159.16667 -76.706666,159.16667 -76.7,159.16667 -76.693334,159.16667 -76.686668,159.16667 -76.680002,159.16667 -76.673336,159.16667 -76.66667))"], "date_created": "Wed, 01 Jan 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 \u0027International Climate Park\u0027 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.\n", "east": 159.41667, "geometry": ["POINT(159.29167 -76.7)"], "keywords": "Allan Hills; Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Ice Core Records; Paleoclimate; Solid Earth", "locations": "Allan Hills; Antarctica", "north": -76.66667, "nsf_funding_programs": null, "persons": "Bender, Michael", "project_titles": "Collaborative Research: Exploring A 2 Million + Year Ice Climate Archive-Allan Hills Blue Ice Area (2MBIA)", "projects": [{"proj_uid": "p0000046", "repository": "USAP-DC", "title": "Collaborative Research: Exploring A 2 Million + Year Ice Climate Archive-Allan Hills Blue Ice Area (2MBIA)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.73333, "title": "Exploring A 2 Million + Year Ice Climate Archive-Allan Hills Blue Ice Area (2MBIA)", "uid": "600099", "west": 159.16667}, {"awards": "0739780 Taylor, Kendrick", "bounds_geometry": ["POINT(-112.117 -79.666)"], "date_created": "Sat, 01 Jan 2011 00:00:00 GMT", "description": "This award supports a project to develop a 2,000-year high-temporal resolution record of biomass burning from the analysis of black carbon in the WAIS Divide bedrock ice core. Pilot data for the WAIS WD05A core demonstrates that we now have the ability to reconstruct this record with minimal impact on the amount of ice available for other projects. The intellectual merit of this project is that black carbon (BC) aerosols result solely from combustion and play a critical but poorly quantified role in global climate forcing and the carbon cycle. When incorporated into snow and ice, BC increases absorption of solar radiation making seasonal snow packs, mountain glaciers, polar ice sheets, and sea ice much more vulnerable to climate warming. BC emissions in the Southern Hemisphere are dominated by biomass burning in the tropical regions of Southern Africa, South America and South Asia. Biomass burning, which results from both climate and human activities, alters the atmospheric composition of greenhouse gases, aerosols and perturbs key biogeochemical cycles. A long-term record of biomass burning is needed to aid in the interpretation of ice core gas composition and will provide important information regarding human impacts on the environment and climate before instrumental records.", "east": -112.117, "geometry": ["POINT(-112.117 -79.666)"], "keywords": "Antarctica; Atmosphere; Black Carbon; Chemistry:ice; Chemistry:Ice; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.666, "nsf_funding_programs": null, "persons": "Taylor, Kendrick C.", "project_titles": "WAIS DIVIDE - High Temporal Resolution Black Carbon Record of Southern Hemisphere Biomass Burning", "projects": [{"proj_uid": "p0000022", "repository": "USAP-DC", "title": "WAIS DIVIDE - High Temporal Resolution Black Carbon Record of Southern Hemisphere Biomass Burning"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.666, "title": "WAIS DIVIDE - High Temporal Resolution Black Carbon Record of Southern Hemisphere Biomass Burning", "uid": "600142", "west": -112.117}]

View results on map Help on results map