{"dp_type": "Dataset", "free_text": "Methane Concentration"}
[{"awards": "1745006 Brook, Edward J.; 2019719 Brook, Edward", "bounds_geometry": ["POINT(159.356125 -76.732376)"], "date_created": "Mon, 06 Jan 2025 00:00:00 GMT", "description": "This dataset contains snapshots of carbon dioxide and methane concentrations, total air content, stable isotope measurements of carbon dioxide, as well as measurements of molecular oxygen and nitrogen and their stable isotopic signatures. Samples come from the ALHIC1901 ice core from the Allan Hills, Antarctica. Where possible, new ages have been assigned to previous measurements from the ALHIC1503 ice core. For samples containing excess CO2 from a secondary source, estimated atmospheric CO2 ranges are included. ", "east": 159.356125, "geometry": ["POINT(159.356125 -76.732376)"], "keywords": "Allan Hills; Antarctica; Blue Ice; Carbon Dioxide; Cryosphere; Methane", "locations": "Allan Hills; Allan Hills; Antarctica", "north": -76.732376, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Marks Peterson, Julia; Brook, Edward; Kalk, Michael; Hishamunda, Valens; Shackleton, Sarah; Severinghaus, Jeffrey P.", "project_titles": "Center for Oldest Ice Exploration; Collaborative research: Snapshots of Early and Mid-Pleistocene Climate and Atmospheric Composition from the Allan Hills Blue Ice Area ", "projects": [{"proj_uid": "p0010253", "repository": "USAP-DC", "title": "Collaborative research: Snapshots of Early and Mid-Pleistocene Climate and Atmospheric Composition from the Allan Hills Blue Ice Area "}, {"proj_uid": "p0010321", "repository": "USAP-DC", "title": "Center for Oldest Ice Exploration"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "COLDEX", "south": -76.732376, "title": "Snapshot record of CO2 and CH4 from the Allan Hills, Antarctica, ranging from 400,000 to 3 million years old", "uid": "601878", "west": 159.356125}, {"awards": "0944021 Brook, Edward J.", "bounds_geometry": ["POLYGON((-163 -79,-162.8 -79,-162.6 -79,-162.4 -79,-162.2 -79,-162 -79,-161.8 -79,-161.6 -79,-161.4 -79,-161.2 -79,-161 -79,-161 -79.05,-161 -79.1,-161 -79.15,-161 -79.2,-161 -79.25,-161 -79.3,-161 -79.35,-161 -79.4,-161 -79.45,-161 -79.5,-161.2 -79.5,-161.4 -79.5,-161.6 -79.5,-161.8 -79.5,-162 -79.5,-162.2 -79.5,-162.4 -79.5,-162.6 -79.5,-162.8 -79.5,-163 -79.5,-163 -79.45,-163 -79.4,-163 -79.35,-163 -79.3,-163 -79.25,-163 -79.2,-163 -79.15,-163 -79.1,-163 -79.05,-163 -79))"], "date_created": "Mon, 13 Jul 2020 00:00:00 GMT", "description": "Data archived here were used to create the Roosevelt Island Ice Core gas age and ice age time scales. Data include methane concentrations, nitrogen and oxygen isotope ratios of N2 and O2, total air content and the D/H ratio of the ice. Derived products included here include ice age and gas age time scales. ", "east": -161.0, "geometry": ["POINT(-162 -79.25)"], "keywords": "Antarctica; CO2; Ice Core; Roosevelt Island", "locations": "Antarctica; Roosevelt Island; Roosevelt Island", "north": -79.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Brook, Edward J.; Lee, James", "project_titles": "Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island", "projects": [{"proj_uid": "p0000272", "repository": "USAP-DC", "title": "Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.5, "title": "Roosevelt Island Ice Core Time Scale and Associated Data", "uid": "601359", "west": -163.0}, {"awards": "1643722 Brook, Edward J.", "bounds_geometry": ["POINT(180 -90)"], "date_created": "Wed, 03 Jun 2020 00:00:00 GMT", "description": "This data set contains measurements of atmospheric methane in the South Pole Ice core made at both Oregon State University and Penn State University, as well as a gas age time scale for the core. In both laboratories methane was measured using a melt-refreeze technique to liberate extracted air and using a gas chromatograph with flame ionization detection to quantify the methane concentration, by comparison to calibrated air standards. To construct the gas time scale abrupt changes in atmospheric methane during the glacial period and centennial methane variability during the Holocene were used to synchronize the South Pole gas record with analogous data from the West Antarctic Ice Sheet Divide ice core. Stratigraphic matching based on visual optimization was verified using an automated matching algorithm. The South Pole ice core recovers all expected changes in methane based on previous records. In combination with an existing ice age scale (Winski et al., 2019, Clim. Past, 15, 1793\u20131808) an independent estimate of the gas age-ice age difference is also provided. A full description of the data and gas age scale are provided in Epifanio et al., 2020 (Climate of the Past, 16, 2431-2444). ", "east": 180.0, "geometry": ["POINT(180 -90)"], "keywords": "Antarctica; Gas Chromatography; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; South Pole", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Brook, Edward J.", "project_titles": "A High Resolution Atmospheric Methane Record from the South Pole Ice Core", "projects": [{"proj_uid": "p0010102", "repository": "USAP-DC", "title": "A High Resolution Atmospheric Methane Record from the South Pole Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "South Pole Ice Core Methane Data and Gas Age Time Scale", "uid": "601329", "west": 180.0}, {"awards": "1443464 Sowers, Todd", "bounds_geometry": ["POINT(0 -90)"], "date_created": "Wed, 11 Dec 2019 00:00:00 GMT", "description": "The overiding goal for our collaborative project is to provide the necessary data to construct an accurate gas age scale all along the SPICE core. Downcore measurements of CH4 and other species would help to constrain the ice age - gas age difference all along the core that is a prerequisite for the construction of the gas age vs depth profile that is the backbone for all atmospheric reconstructions. ", "east": 0.0, "geometry": ["POINT(0 -90)"], "keywords": "Antarctica; Atmospheric CH4; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Data; Methane; Methane Concentration; Snow/ice; Snow/Ice; South Pole; SPICEcore", "locations": "South Pole; Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Sowers, Todd A.", "project_titles": "Collaborative Research: Inert Gas and Methane Based Climate Records throughout the South Pole Deep Ice Core", "projects": [{"proj_uid": "p0010005", "repository": "USAP-DC", "title": "Collaborative Research: Inert Gas and Methane Based Climate Records throughout the South Pole Deep Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "South Pole CH4 data for termination", "uid": "601230", "west": 0.0}, {"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": "Antarctica; WAIS Divide", "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": "0839031 Severinghaus, Jeffrey", "bounds_geometry": ["POINT(161.71965 -77.76165)"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This award supports a project to develop a precise gas-based chronology for an archive of large-volume samples of the ancient atmosphere, which would enable ultra-trace gas measurements that are currently precluded by sample size limitations of ice cores. The intellectual merit of the proposed work is that it will provide a critical test of the \u0027clathrate hypothesis\u0027 that methane clathrates contributed to the two abrupt atmospheric methane concentration increases during the last deglaciation 15 and 11 kyr ago. This approach employs large volumes of ice (\u003e1 ton) to measure carbon-14 on past atmospheric methane across the abrupt events. Carbon-14 is an ideal discriminator of fossil sources of methane to the atmosphere, because most methane sources (e.g., wetlands, termites, biomass burning) are rich in carbon-14, whereas clathrates and other fossil sources are devoid of carbon-14. The proposed work is a logical extension to Taylor Glacier, Antarctica, of an approach pioneered at the margin of the Greenland ice sheet over the past 7 years. The Greenland work found higher-than-expected carbon-14 values, likely due in part to contaminants stemming from the high impurity content of Greenland ice and the interaction of the ice with sediments from the glacier bed. The data also pointed to the possibility of a previously unknown process, in-situ cosmogenic production of carbon-14 methane (radiomethane) in the ice matrix. Antarctic ice in Taylor Glacier is orders of magnitude cleaner than the ice at the Greenland site, and is much colder and less stratigraphically disturbed, offering the potential for a clear resolution of this puzzle and a definitive test of the cosmogenic radiomethane hypothesis. Even if cosmogenic radiomethane in ice is found, it still may be possible to reconstruct atmospheric radiomethane with a correction enabled by a detailed understanding of the process, which will be sought by co-measuring carbon-14 in carbon monoxide and carbon dioxide. The broader impacts of the proposed work are that the clathrate test may shed light on the stability of the clathrate reservoir and its potential for climate feedbacks under human-induced warming. Development of Taylor Glacier as a \u0027horizontal ice core\u0027 would provide a community resource for other researchers. Education of one postdoc, one graduate student, and one undergraduate, would add to human resources. This award has field work in Antarctica.", "east": 161.71965, "geometry": ["POINT(161.71965 -77.76165)"], "keywords": "Antarctica; Cosmogenic; Geochemistry; Ice Core Records; Paleoclimate; Radiocarbon; Taylor Glacier; Transantarctic Mountains", "locations": "Taylor Glacier; Transantarctic Mountains; Antarctica", "north": -77.76165, "nsf_funding_programs": null, "persons": "Severinghaus, Jeffrey P.", "project_titles": "Collaborative Research: A \"Horizontal Ice Core\" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica", "projects": [{"proj_uid": "p0000099", "repository": "USAP-DC", "title": "Collaborative Research: A \"Horizontal Ice Core\" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.76165, "title": "Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica", "uid": "600165", "west": 161.71965}, {"awards": "1043518 Brook, Edward J.; 1142041 Brook, Edward J.; 0944552 Brook, Edward J.; 0839093 McConnell, Joseph; 1142166 McConnell, Joseph", "bounds_geometry": ["POINT(-112.05 -79.28)"], "date_created": "Thu, 23 Jul 2015 00:00:00 GMT", "description": "This data set contains methane concentrations from a West Antarctic Ice Sheet (WAIS) Divide ice core obtained by an online, continuous technique (Stowasser, et al. 2012). \u003cbr\u003e\u003c/br\u003e IMPORTANT NOTE: The experiment-time-integrated data are made available as a comprehensive archive of WAIS-Divide methane measurements. In the vast majority of cases the 2-yearly spline fit will be the most suitable for your application (Rhodes_Science_2015_WD_CH4_noaa-wdc-paleo (8).xlsx or Rhodes_Science_2015_WD_CH4_noaa-wdc-paleo.txt). \u003cbr\u003e \u003c/br\u003e For more detailed information on the 2 yearly cubic smoothing spline please refer to references listed, in particular, the Supplementary Material of Rhodes et al. (2015).", "east": -112.05, "geometry": ["POINT(-112.05 -79.28)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "locations": "Antarctica; WAIS Divide", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology", "persons": "McConnell, Joseph; Brook, Edward J.; Rhodes, Rachel", "project_titles": "Collaborative Research: Completing an ultra-high resolution methane record from the WAIS Divide ice core", "projects": [{"proj_uid": "p0000185", "repository": "USAP-DC", "title": "Collaborative Research: Completing an ultra-high resolution methane record from the WAIS Divide ice core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.28, "title": "Continuous, Ultra-high Resolution WAIS-Divide Ice Core Methane Record 9.8-67.2 ka BP", "uid": "609628", "west": -112.05}, {"awards": "0944584 Sowers, Todd; 0538578 Brook, Edward J.; 0538538 Sowers, Todd", "bounds_geometry": ["POINT(-38.5 72.6)", "POINT(-112.0865 -79.4676)"], "date_created": "Fri, 31 Jan 2014 00:00:00 GMT", "description": "This data set measures methane concentrations in ancient air trapped in the West Antarctic Ice Sheet (WAIS) Divide and Greenland Ice Sheet Project (GISP2) ice cores; presenting two, high-resolution ice core methane records of the past 2500 years, one from each pole. These measurements were used to reconstruct the methane Inter-Polar Difference (IPD) during the late Holocene. Also included are model results of methane emissions that were presented in the manuscript describing this data set.", "east": -38.5, "geometry": ["POINT(-38.5 72.6)", "POINT(-112.0865 -79.4676)"], "keywords": "Antarctica; Arctic; Chemistry:fluid; Chemistry:Fluid; Geochemistry; GISP2; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "locations": "Antarctica; WAIS Divide; Arctic", "north": 72.6, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Mitchell, Logan E", "project_titles": "Collaborative Research: Constructing an Ultra-high Resolution Atmospheric Methane Record for the Last 140,000 Years from WAIS Divide Core.", "projects": [{"proj_uid": "p0000025", "repository": "USAP-DC", "title": "Collaborative Research: Constructing an Ultra-high Resolution Atmospheric Methane Record for the Last 140,000 Years from WAIS Divide Core."}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.4676, "title": "Late Holocene Methane Concentrations from WAIS Divide and GISP2", "uid": "609586", "west": -112.0865}, {"awards": "0538538 Sowers, Todd", "bounds_geometry": ["POINT(-112.086483 -79.46763)"], "date_created": "Thu, 19 Apr 2012 00:00:00 GMT", "description": "This data set contains a high-resolution history of atmospheric methane (CH4) concentrations in parts per billion (ppb) from approximately 60 to 11,300 years before present (ybp), obtained in 2010 from the West Antarctic Ice Sheet (WAIS) Divide Ice Core WDC06A. Gas age is derived from the WDC06A-5 ice age scale.\n\nData are available via FTP as a Microsoft Excel file (.xlsx).", "east": -112.086483, "geometry": ["POINT(-112.086483 -79.46763)"], "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Methane; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "locations": "Antarctica; WAIS Divide", "north": -79.46763, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Sowers, Todd A.", "project_titles": "Collaborative Research: Constructing an Ultra-high Resolution Atmospheric Methane Record for the Last 140,000 Years from WAIS Divide Core.", "projects": [{"proj_uid": "p0000025", "repository": "USAP-DC", "title": "Collaborative Research: Constructing an Ultra-high Resolution Atmospheric Methane Record for the Last 140,000 Years from WAIS Divide Core."}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.46763, "title": "Methane Concentrations from the WAIS Divide Ice Core (WDC06A), 60 to 11,300 ybp", "uid": "609509", "west": -112.086483}, {"awards": "0739780 Taylor, Kendrick; 0538578 Brook, Edward J.; 0520523 Brook, Edward J.; 0538538 Sowers, Todd; 0538427 McConnell, Joseph", "bounds_geometry": ["POINT(112.09 -79.47)"], "date_created": "Fri, 27 May 2011 00:00:00 GMT", "description": "This data set provides a high-precision and high-resolution record of atmospheric methane from the West Antarctic Ice Sheet (WAIS) Divide ice core WDC05A, spanning the years 1000 to 1800 C.E. The data include methane (CH4) concentration measurements and ice age chronology. Methane concentration data include mean sample depth, gas age, mean concentration, and concentrations from individual measurements, at a temporal resolution of approximately nine years. Ice chronology data include depth and ice age.\n\nData are available via FTP, in Microsoft Excel (.xlsx) format.", "east": 112.09, "geometry": ["POINT(112.09 -79.47)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.47, "nsf_funding_programs": "Antarctic Glaciology", "persons": "McConnell, Joseph; Brook, Edward J.; Mitchell, Logan E; Sowers, Todd A.; Taylor, Kendrick C.", "project_titles": "Collaborative Research: Gases in Firn Air and Shallow Ice at the Proposed WAIS Divide Drilling Site", "projects": [{"proj_uid": "p0000368", "repository": "USAP-DC", "title": "Collaborative Research: Gases in Firn Air and Shallow Ice at the Proposed WAIS Divide Drilling Site"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.47, "title": "Methane Concentration and Chronology from the WAIS Divide Ice Core (WDC05A)", "uid": "609493", "west": 112.09}, {"awards": "0520523 Brook, Edward J.", "bounds_geometry": ["POINT(-38.466667 73.583333)", "POINT(-148.81 -81.65)"], "date_created": "Wed, 09 Dec 2009 00:00:00 GMT", "description": "This data set contains methane measurements made in trapped air in the Holocene sections of two ice cores: the Siple Dome ice core in Antarctica, and the Greenland Ice Sheet Project 2 (GISP2) ice core in Greenland. The measurements were made at Oregon State University between 2007 and 2009. Measurements were made relative to the NOAA04 methane concentration scale using a working standard internally calibrated to NOAA certified air standards. Concentrations are corrected for gravitational fractionation and solubility effects in the melt-refreeze extraction. Data are available via FTP in Microsoft Excel (.xls) format.", "east": -38.466667, "geometry": ["POINT(-38.466667 73.583333)", "POINT(-148.81 -81.65)"], "keywords": "Antarctica; Arctic; Chemistry:fluid; Chemistry:Fluid; Geochemistry; GISP2; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "locations": "Arctic; Antarctica; Siple Dome", "north": 73.583333, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Brook, Edward J.", "project_titles": "Collaborative Research: New insights into the Holocene methane budget from dual isotope systematics and a high resolution record of the interpolar gradient", "projects": [{"proj_uid": "p0000131", "repository": "USAP-DC", "title": "Collaborative Research: New insights into the Holocene methane budget from dual isotope systematics and a high resolution record of the interpolar gradient"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.65, "title": "Methane Measurements from the GISP2 and Siple Dome Ice Cores", "uid": "609440", "west": -148.81}, {"awards": "0126057 Brook, Edward J.", "bounds_geometry": ["POINT(-38.466667 72.5833333)"], "date_created": "Tue, 16 Dec 2008 00:00:00 GMT", "description": "This ice core data is archived at the World Data Center for Paleoclimatology and is available through the Ice Core Data Gateway. The data includes methane data from the Greenland Ice Sheet Project 2 (GISP2). GISP2 is an ice core project that drilled through the Greenland ice sheet and 1.55 meters into bedrock. The ice core is 3053.44 meters in depth, the deepest ice core recovered in the world at the time. The ice core was completed in 1993 after five years of drilling.\n\nMethane concentrations were determined by GC-FID using standards calibrated by NOAA CMDL. \t\t\t\t\t\nThe gas age time scales and analytical techniques are described in further detail in the publication.", "east": -38.466667, "geometry": ["POINT(-38.466667 72.5833333)"], "keywords": "Antarctica; Arctic; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; GISP2; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Methane; Paleoclimate; Taylor Dome", "locations": "Antarctica; Taylor Dome; Arctic", "north": 72.5833333, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Brook, Edward J.", "project_titles": "High Resolution Records of Atmospheric Methane in Ice Cores and Implications for Late Quaternary Climate Change", "projects": [{"proj_uid": "p0000034", "repository": "USAP-DC", "title": "High Resolution Records of Atmospheric Methane in Ice Cores and Implications for Late Quaternary Climate Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": 72.5833333, "title": "GISP2 (D Core) Methane Concentration Data", "uid": "609360", "west": -38.466667}, {"awards": "0512971 Brook, Edward J.", "bounds_geometry": ["POINT(-38.466667 72.5833333)"], "date_created": "Wed, 14 May 2003 00:00:00 GMT", "description": "The data include methane data from the Greenland Ice Sheet Project 2 (GISP2) B \u0026 D Cores. Gas ages were calculated according to the methods described in Brook et\nal. 1996, and are subject to change. Ice ages were calculated by by\nlinear interpolation from the Meese et al. timescale.\n", "east": -38.466667, "geometry": ["POINT(-38.466667 72.5833333)"], "keywords": "Arctic; Chemistry:fluid; Chemistry:Fluid; Chemistry:ice; Chemistry:Ice; Geochemistry; GISP2; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland; Ice Core Records; Methane; Paleoclimate", "locations": "Greenland; Arctic", "north": 72.5833333, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Brook, Edward J.", "project_titles": "High Resolution Records of Atmospheric Methane in Ice Cores and Implications for Late Quaternary Climate Change", "projects": [{"proj_uid": "p0000034", "repository": "USAP-DC", "title": "High Resolution Records of Atmospheric Methane in Ice Cores and Implications for Late Quaternary Climate Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": 72.5833333, "title": "GISP2 (B and D Core) Methane Concentrations", "uid": "609125", "west": -38.466667}]
X
X
Help on the Results MapX
This window can be dragged by its header, and can be resized from the bottom right corner.
Clicking the Layers button - the blue square in the top left of the Results Map - will display a list of map layers you can add or remove
from the currently displayed map view.
The Results Map and the Results Table
- The Results Map displays the centroids of the geographic bounds of all the results returned by the search.
- Results that are displayed in the current map view will be highlighted in blue and brought to the top of the Results Table.
- As the map is panned or zoomed, the highlighted rows in the table will update.
- If you click on a centroid on the map, it will turn yellow and display a popup with details for that project/dataset - including a link to the landing page. The bounds for the project(s)/dataset(s) selected will be displayed in red. The selected result(s) will be highlighted in red and brought to the top of the table.
- The default table sorting order is: Selected, Visible, Date (descending), but this can be changed by clicking on column headers in the table.
- Selecting Show on Map for an individual row will both display the geographic bounds for that result on a mini map, and also display the bounds and highlight the centroid on the Results Map.
- Clicking the 'Show boundaries' checkbox at the top of the Results Map will display all the bounds for the filtered results.
Defining a search area on the Results Map
- If you click on the Rectangle or Polygon icons in the top right of the Results Map, you can define a search area which will be added to any other search criteria already selected.
- After you have drawn a polygon, you can edit it using the Edit Geometry dropdown in the search form at the top.
- Clicking Clear in the map will clear any drawn polygon.
- Clicking Search in the map, or Search on the form will have the same effect.
- The returned results will be any projects/datasets with bounds that intersect the polygon.
- Use the Exclude project/datasets checkbox to exclude any projects/datasets that cover the whole Antarctic region.
Viewing map layers on the Results Map
To sort the table of search results, click the header of the column you wish to search by. To sort by multiple columns, hold down the shift key whilst selecting the sort columns in order.
Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
---|---|---|---|---|---|---|---|---|---|
Snapshot record of CO2 and CH4 from the Allan Hills, Antarctica, ranging from 400,000 to 3 million years old
|
1745006 2019719 |
2025-01-06 | Marks Peterson, Julia; Brook, Edward; Kalk, Michael; Hishamunda, Valens; Shackleton, Sarah; Severinghaus, Jeffrey P. |
Collaborative research: Snapshots of Early and Mid-Pleistocene Climate and Atmospheric Composition from the Allan Hills Blue Ice Area Center for Oldest Ice Exploration |
This dataset contains snapshots of carbon dioxide and methane concentrations, total air content, stable isotope measurements of carbon dioxide, as well as measurements of molecular oxygen and nitrogen and their stable isotopic signatures. Samples come from the ALHIC1901 ice core from the Allan Hills, Antarctica. Where possible, new ages have been assigned to previous measurements from the ALHIC1503 ice core. For samples containing excess CO2 from a secondary source, estimated atmospheric CO2 ranges are included. | ["POINT(159.356125 -76.732376)"] | ["POINT(159.356125 -76.732376)"] | false | false |
Roosevelt Island Ice Core Time Scale and Associated Data
|
0944021 |
2020-07-13 | Brook, Edward J.; Lee, James |
Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island |
Data archived here were used to create the Roosevelt Island Ice Core gas age and ice age time scales. Data include methane concentrations, nitrogen and oxygen isotope ratios of N2 and O2, total air content and the D/H ratio of the ice. Derived products included here include ice age and gas age time scales. | ["POLYGON((-163 -79,-162.8 -79,-162.6 -79,-162.4 -79,-162.2 -79,-162 -79,-161.8 -79,-161.6 -79,-161.4 -79,-161.2 -79,-161 -79,-161 -79.05,-161 -79.1,-161 -79.15,-161 -79.2,-161 -79.25,-161 -79.3,-161 -79.35,-161 -79.4,-161 -79.45,-161 -79.5,-161.2 -79.5,-161.4 -79.5,-161.6 -79.5,-161.8 -79.5,-162 -79.5,-162.2 -79.5,-162.4 -79.5,-162.6 -79.5,-162.8 -79.5,-163 -79.5,-163 -79.45,-163 -79.4,-163 -79.35,-163 -79.3,-163 -79.25,-163 -79.2,-163 -79.15,-163 -79.1,-163 -79.05,-163 -79))"] | ["POINT(-162 -79.25)"] | false | false |
South Pole Ice Core Methane Data and Gas Age Time Scale
|
1643722 |
2020-06-03 | Brook, Edward J. |
A High Resolution Atmospheric Methane Record from the South Pole Ice Core |
This data set contains measurements of atmospheric methane in the South Pole Ice core made at both Oregon State University and Penn State University, as well as a gas age time scale for the core. In both laboratories methane was measured using a melt-refreeze technique to liberate extracted air and using a gas chromatograph with flame ionization detection to quantify the methane concentration, by comparison to calibrated air standards. To construct the gas time scale abrupt changes in atmospheric methane during the glacial period and centennial methane variability during the Holocene were used to synchronize the South Pole gas record with analogous data from the West Antarctic Ice Sheet Divide ice core. Stratigraphic matching based on visual optimization was verified using an automated matching algorithm. The South Pole ice core recovers all expected changes in methane based on previous records. In combination with an existing ice age scale (Winski et al., 2019, Clim. Past, 15, 1793–1808) an independent estimate of the gas age-ice age difference is also provided. A full description of the data and gas age scale are provided in Epifanio et al., 2020 (Climate of the Past, 16, 2431-2444). | ["POINT(180 -90)"] | ["POINT(180 -90)"] | false | false |
South Pole CH4 data for termination
|
1443464 |
2019-12-11 | Sowers, Todd A. |
Collaborative Research: Inert Gas and Methane Based Climate Records throughout the South Pole Deep Ice Core |
The overiding goal for our collaborative project is to provide the necessary data to construct an accurate gas age scale all along the SPICE core. Downcore measurements of CH4 and other species would help to constrain the ice age - gas age difference all along the core that is a prerequisite for the construction of the gas age vs depth profile that is the backbone for all atmospheric reconstructions. | ["POINT(0 -90)"] | ["POINT(0 -90)"] | false | false |
Methane concentration in Allan Hills ice cores
|
1443263 |
2019-08-14 | Yan, Yuzhen; Bender, Michael; Brook, Edward J.; Higgins, John |
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 |
This file includes the concentration methane (CH4) in Allan Hills ice cores (ALHIC1502 and ALHIC1503). | ["POINT(159.35507 -76.73286)"] | ["POINT(159.35507 -76.73286)"] | false | false |
WD2014: Timescale for WAIS Divide Core 2006 A (WDC-06A)
|
0944197 |
2017-03-28 | Fudge, T. J. |
Collaborative Research: Establishing the Chronology and Histories of Accumulation and Ice Dynamics for the WAIS Divide Core |
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\". We 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. | ["POINT(-112.1115 -79.481)"] | ["POINT(-112.1115 -79.481)"] | false | false |
Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica
|
0839031 |
2016-01-01 | Severinghaus, Jeffrey P. |
Collaborative Research: A "Horizontal Ice Core" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica |
This award supports a project to develop a precise gas-based chronology for an archive of large-volume samples of the ancient atmosphere, which would enable ultra-trace gas measurements that are currently precluded by sample size limitations of ice cores. The intellectual merit of the proposed work is that it will provide a critical test of the 'clathrate hypothesis' that methane clathrates contributed to the two abrupt atmospheric methane concentration increases during the last deglaciation 15 and 11 kyr ago. This approach employs large volumes of ice (>1 ton) to measure carbon-14 on past atmospheric methane across the abrupt events. Carbon-14 is an ideal discriminator of fossil sources of methane to the atmosphere, because most methane sources (e.g., wetlands, termites, biomass burning) are rich in carbon-14, whereas clathrates and other fossil sources are devoid of carbon-14. The proposed work is a logical extension to Taylor Glacier, Antarctica, of an approach pioneered at the margin of the Greenland ice sheet over the past 7 years. The Greenland work found higher-than-expected carbon-14 values, likely due in part to contaminants stemming from the high impurity content of Greenland ice and the interaction of the ice with sediments from the glacier bed. The data also pointed to the possibility of a previously unknown process, in-situ cosmogenic production of carbon-14 methane (radiomethane) in the ice matrix. Antarctic ice in Taylor Glacier is orders of magnitude cleaner than the ice at the Greenland site, and is much colder and less stratigraphically disturbed, offering the potential for a clear resolution of this puzzle and a definitive test of the cosmogenic radiomethane hypothesis. Even if cosmogenic radiomethane in ice is found, it still may be possible to reconstruct atmospheric radiomethane with a correction enabled by a detailed understanding of the process, which will be sought by co-measuring carbon-14 in carbon monoxide and carbon dioxide. The broader impacts of the proposed work are that the clathrate test may shed light on the stability of the clathrate reservoir and its potential for climate feedbacks under human-induced warming. Development of Taylor Glacier as a 'horizontal ice core' would provide a community resource for other researchers. Education of one postdoc, one graduate student, and one undergraduate, would add to human resources. This award has field work in Antarctica. | ["POINT(161.71965 -77.76165)"] | ["POINT(161.71965 -77.76165)"] | false | false |
Continuous, Ultra-high Resolution WAIS-Divide Ice Core Methane Record 9.8-67.2 ka BP
|
1043518 1142041 0944552 0839093 1142166 |
2015-07-23 | McConnell, Joseph; Brook, Edward J.; Rhodes, Rachel |
Collaborative Research: Completing an ultra-high resolution methane record from the WAIS Divide ice core |
This data set contains methane concentrations from a West Antarctic Ice Sheet (WAIS) Divide ice core obtained by an online, continuous technique (Stowasser, et al. 2012). <br></br> IMPORTANT NOTE: The experiment-time-integrated data are made available as a comprehensive archive of WAIS-Divide methane measurements. In the vast majority of cases the 2-yearly spline fit will be the most suitable for your application (Rhodes_Science_2015_WD_CH4_noaa-wdc-paleo (8).xlsx or Rhodes_Science_2015_WD_CH4_noaa-wdc-paleo.txt). <br> </br> For more detailed information on the 2 yearly cubic smoothing spline please refer to references listed, in particular, the Supplementary Material of Rhodes et al. (2015). | ["POINT(-112.05 -79.28)"] | ["POINT(-112.05 -79.28)"] | false | false |
Late Holocene Methane Concentrations from WAIS Divide and GISP2
|
0944584 0538578 0538538 |
2014-01-31 | Mitchell, Logan E |
Collaborative Research: Constructing an Ultra-high Resolution Atmospheric Methane Record for the Last 140,000 Years from WAIS Divide Core. |
This data set measures methane concentrations in ancient air trapped in the West Antarctic Ice Sheet (WAIS) Divide and Greenland Ice Sheet Project (GISP2) ice cores; presenting two, high-resolution ice core methane records of the past 2500 years, one from each pole. These measurements were used to reconstruct the methane Inter-Polar Difference (IPD) during the late Holocene. Also included are model results of methane emissions that were presented in the manuscript describing this data set. | ["POINT(-38.5 72.6)", "POINT(-112.0865 -79.4676)"] | ["POINT(-38.5 72.6)", "POINT(-112.0865 -79.4676)"] | false | false |
Methane Concentrations from the WAIS Divide Ice Core (WDC06A), 60 to 11,300 ybp
|
0538538 |
2012-04-19 | Sowers, Todd A. |
Collaborative Research: Constructing an Ultra-high Resolution Atmospheric Methane Record for the Last 140,000 Years from WAIS Divide Core. |
This data set contains a high-resolution history of atmospheric methane (CH4) concentrations in parts per billion (ppb) from approximately 60 to 11,300 years before present (ybp), obtained in 2010 from the West Antarctic Ice Sheet (WAIS) Divide Ice Core WDC06A. Gas age is derived from the WDC06A-5 ice age scale. Data are available via FTP as a Microsoft Excel file (.xlsx). | ["POINT(-112.086483 -79.46763)"] | ["POINT(-112.086483 -79.46763)"] | false | false |
Methane Concentration and Chronology from the WAIS Divide Ice Core (WDC05A)
|
0739780 0538578 0520523 0538538 0538427 |
2011-05-27 | McConnell, Joseph; Brook, Edward J.; Mitchell, Logan E; Sowers, Todd A.; Taylor, Kendrick C. |
Collaborative Research: Gases in Firn Air and Shallow Ice at the Proposed WAIS Divide Drilling Site |
This data set provides a high-precision and high-resolution record of atmospheric methane from the West Antarctic Ice Sheet (WAIS) Divide ice core WDC05A, spanning the years 1000 to 1800 C.E. The data include methane (CH4) concentration measurements and ice age chronology. Methane concentration data include mean sample depth, gas age, mean concentration, and concentrations from individual measurements, at a temporal resolution of approximately nine years. Ice chronology data include depth and ice age. Data are available via FTP, in Microsoft Excel (.xlsx) format. | ["POINT(112.09 -79.47)"] | ["POINT(112.09 -79.47)"] | false | false |
Methane Measurements from the GISP2 and Siple Dome Ice Cores
|
0520523 |
2009-12-09 | Brook, Edward J. |
Collaborative Research: New insights into the Holocene methane budget from dual isotope systematics and a high resolution record of the interpolar gradient |
This data set contains methane measurements made in trapped air in the Holocene sections of two ice cores: the Siple Dome ice core in Antarctica, and the Greenland Ice Sheet Project 2 (GISP2) ice core in Greenland. The measurements were made at Oregon State University between 2007 and 2009. Measurements were made relative to the NOAA04 methane concentration scale using a working standard internally calibrated to NOAA certified air standards. Concentrations are corrected for gravitational fractionation and solubility effects in the melt-refreeze extraction. Data are available via FTP in Microsoft Excel (.xls) format. | ["POINT(-38.466667 73.583333)", "POINT(-148.81 -81.65)"] | ["POINT(-38.466667 73.583333)", "POINT(-148.81 -81.65)"] | false | false |
GISP2 (D Core) Methane Concentration Data
|
0126057 |
2008-12-16 | Brook, Edward J. |
High Resolution Records of Atmospheric Methane in Ice Cores and Implications for Late Quaternary Climate Change |
This ice core data is archived at the World Data Center for Paleoclimatology and is available through the Ice Core Data Gateway. The data includes methane data from the Greenland Ice Sheet Project 2 (GISP2). GISP2 is an ice core project that drilled through the Greenland ice sheet and 1.55 meters into bedrock. The ice core is 3053.44 meters in depth, the deepest ice core recovered in the world at the time. The ice core was completed in 1993 after five years of drilling. Methane concentrations were determined by GC-FID using standards calibrated by NOAA CMDL. The gas age time scales and analytical techniques are described in further detail in the publication. | ["POINT(-38.466667 72.5833333)"] | ["POINT(-38.466667 72.5833333)"] | false | false |
GISP2 (B and D Core) Methane Concentrations
|
0512971 |
2003-05-14 | Brook, Edward J. |
High Resolution Records of Atmospheric Methane in Ice Cores and Implications for Late Quaternary Climate Change |
The data include methane data from the Greenland Ice Sheet Project 2 (GISP2) B & D Cores. Gas ages were calculated according to the methods described in Brook et al. 1996, and are subject to change. Ice ages were calculated by by linear interpolation from the Meese et al. timescale. | ["POINT(-38.466667 72.5833333)"] | ["POINT(-38.466667 72.5833333)"] | false | false |