{"NOAAStudyId":"17826","contactInfo":{"address":"325 Broadway, E/NE31","city":"Boulder","constraints":"Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site.","country":"USA","dataCenterUrl":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data","email":"paleo@noaa.gov","fax":"303-497-6513","longName":"National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce ","phone":"303-497-6280","postalCode":"80305-3328","shortName":"DOC/NOAA/NESDIS/NCEI","state":"CO","type":"CONTACT INFORMATION"},"contributionDate":"1997-11-30","dataPublisher":"NOAA","dataType":"ICE CORES","dataTypeInformation":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/ice-core","difMetadataLink":"http://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-icecore-17826.xml","doi":null,"earliestYearBP":38646,"earliestYearCE":-36696,"entryId":"noaa-icecore-17826","funding":[],"investigators":"Sowers, T.; Brook, E.J.; Etheridge, D.M.; Blunier, T.; Fuchs, A.; Leuenberger, M.; Chappellaz, J.A.; Barnola, J.M.; Wahlen, M.; Deck, B.; Weyhenmeyer, C.","mostRecentYearBP":169,"mostRecentYearCE":1781,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/17826","originalSource":null,"publication":[{"abstract":"We undertook an interlaboratory comparison of techniques used to extract and analyze trapped gases in ice cores. The intercomparison included analyses of standard reference gases and samples of ice from the Greenland Ice Sheet Project 2 (GISP2) site. Concentrations of CO2, CH4, the d18O of O2, the d15N of N2, and the O2/N2, and Ar/N2 ratios were measured in air standards and ice core samples. The standard reference scales for CO2 and CH4 were consistent at the +/-2% level. The dO2/N2 and d18O of O2 measurements showed substantial deviations between the two laboratories able to measure these ratios. The deviations are probably related to errors associated with calibration of the working standards. The dArN2 and d15N of N2 measurements were consistent. Five laboratories analyzed the CH4 concentration in a 4.2-m section of the GISP2 ice core. The average of 20 discrete CH4 measurements was 748+/-10 parts per billion by volume (ppbv). The standard deviation of these measurements was close to the total analytical uncertainty associated with the measurements. In all cases, those laboratories employing a dry extraction technique determined higher CH4 values than laboratories using a wet extraction technique. The origin of this difference is unclear but may involve uncertainties associated with blank corrections. Analyses of the CO2 concentration of trapped gases showed extreme variations which cannot be explained by analytical uncertainties alone. Three laboratories measured the [CO2] on 21 discrete depths yielding an average value of 283+/-13 parts per million by volume (ppmv). In this case, the standard deviation was roughly a factor of 2 greater than the analytical uncertainties. We believe the variability in the measured [CO2] results from impurities in the ice which may have compromised the [CO2] of trapped gases in Greenland ice.","author":{"name":"Todd Sowers, Ed Brook, David Etheridge, Thomas Blunier, Andreas Fuchs, Markus Leuenberger, Jerome Chappellaz, Jean Marc Barnola, Martin Wahlen, Bruce Deck, Connie Weyhenmeyer"},"citation":"Todd Sowers, Ed Brook, David Etheridge, Thomas Blunier, Andreas Fuchs, Markus Leuenberger, Jerome Chappellaz, Jean Marc Barnola, Martin Wahlen, Bruce Deck, Connie Weyhenmeyer. 1997. An interlaboratory comparison of techniques for extracting and analyzing trapped gases in ice cores. Journal of Geophysical Research: Oceans, 102(C12), 26527-26538. doi: 10.1029/97JC00633","edition":null,"identifier":{"id":"10.1029/97JC00633","type":"doi","url":"http://dx.doi.org/10.1029/97JC00633"},"issue":"C12","journal":"Journal of Geophysical Research: Oceans","pages":"26527-26538","pubRank":"1","pubYear":1997,"reportNumber":null,"title":"An interlaboratory comparison of techniques for extracting and analyzing trapped gases in ice cores","type":"publication","volume":"102"}],"reconstruction":"N","scienceKeywords":null,"site":[{"NOAASiteId":"19978","geo":{"geoType":"Feature","geometry":{"coordinates":["72.6","-38.5"],"type":"POINT"},"properties":{"easternmostLongitude":"-38.5","maxElevationMeters":"3200","minElevationMeters":"3200","northernmostLatitude":"72.6","southernmostLatitude":"72.6","westernmostLongitude":"-38.5"}},"locationName":"Continent>North America>Greenland","mappable":"Y","paleoData":[{"NOAADataTableId":"28144","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>ice core>atmospheric gas"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/gases/gascomp.txt","linkText":"GISP2 Extraction methods for nitrogen and oxygen isotopes","urlDescription":"Data File","variables":[{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":null,"cvWhat":"sampling metadata>sample identification"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"meter","cvWhat":"depth variable>depth"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"chemical composition>element or single-element molecule>nitrogen gas","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"chemical composition>element or single-element molecule>nitrogen gas","cvMethod":"wet extraction","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"chemical composition>element or single-element molecule>oxygen gas","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":null,"cvDataType":"ICE 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spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":"gravitationally corrected","cvDataType":"ICE CORES","cvDetail":"corrected","cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"wet extraction","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"}]},{"NOAAKeywords":["earth science>paleoclimate>ice core>atmospheric gas"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/gases/gas.txt","linkText":"GISP2 Isotope Concentrations in Trapped Air","urlDescription":"Data File","variables":[{"cvAdditionalInfo":"gravitationally corrected","cvDataType":"ICE CORES","cvDetail":"corrected","cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>element or compound ratio>delta CO2/N2"},{"cvAdditionalInfo":"gravitationally corrected","cvDataType":"ICE CORES","cvDetail":"corrected","cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>element or compound ratio>delta O2/Ar"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"calendar year before present","cvWhat":"age variable>age>ice age at sample end"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"calendar year before present","cvWhat":"age variable>age>ice age at sample start"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"meter","cvWhat":"depth variable>depth>depth at sample start"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"meter","cvWhat":"depth variable>depth>depth at sample end"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"chemical composition>element or single-element molecule>nitrogen gas","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"chemical composition>element or single-element molecule>oxygen gas","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":"gravitationally corrected","cvDataType":"ICE CORES","cvDetail":"corrected","cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":"gravitationally corrected","cvDataType":"ICE CORES","cvDetail":"corrected","cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>element or compound ratio>delta O2/N2"},{"cvAdditionalInfo":"gravitationally corrected","cvDataType":"ICE CORES","cvDetail":"corrected","cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>element or compound ratio>delta Ar/N2"}]}],"dataTableName":"GISP21997GasIso","dataTableNotes":null,"earliestYear":38646,"earliestYearBP":38646,"earliestYearCE":-36696,"mostRecentYear":169,"mostRecentYearBP":169,"mostRecentYearCE":1781,"species":[],"timeUnit":"cal yr BP"}],"siteName":"GISP2"}],"studyCode":null,"studyName":"GISP2 Ice Core Isotope Concentrations in Trapped Air","studyNotes":"Gas isotopes from 72 - 2235 meters depth.  All data are presented using\nthe delta notation where the standard is the present day atmosphere. The\nnumbers in the column headings refer to the mass of the gas in question\n(ie. 32=16 O2, oxygen, 28=14 N2, nitrogen, 40=argon, 44 = CO2).","version":"1.0","xmlId":"15519"}