{"NOAAStudyId":"2491","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":"2006-07-01","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-2491.xml","doi":null,"earliestYearBP":12220,"earliestYearCE":-10270,"entryId":"noaa-icecore-2491","funding":[],"investigators":"Schaefer, H.; Whiticar, M.J.; Brook, E.J.; Petrenko, V.V.; Ferretti, D.F.; Severinghaus, J.","mostRecentYearBP":11360,"mostRecentYearCE":-9410,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/2491","originalSource":null,"publication":[{"abstract":null,"author":null,"citation":"Schaefer, H., M.J. Whiticar, E.J. Brook, V.V. Petrenko, D.F. Ferretti, and J.P. Severinghaus.  2006.  Ice Record of d13C for Atmospheric CH4 Across the Younger DryasŋPreboreal Transition. Science, Vol. 313, pp. 1109-1112, 25 August 2006.","edition":null,"identifier":null,"issue":null,"journal":"Science","pages":null,"pubRank":"1","pubYear":2006,"reportNumber":null,"title":"Ice Record of d13C for Atmospheric CH4 Across the Younger DryasŋPreboreal Transition","type":"publication","volume":null}],"reconstruction":"N","scienceKeywords":null,"site":[{"NOAASiteId":"20012","geo":{"geoType":"Feature","geometry":{"coordinates":["69.48","-50.8"],"type":"POINT"},"properties":{"easternmostLongitude":"-50.8","maxElevationMeters":null,"minElevationMeters":null,"northernmostLatitude":"69.48","southernmostLatitude":"69.48","westernmostLongitude":"-50.8"}},"locationName":"Continent>North America>Greenland","mappable":"Y","paleoData":[{"NOAADataTableId":"38157","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>ice core>carbon isotopes","earth science>paleoclimate>ice core>atmospheric gas"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/pakitsoq2006d13ch4.txt","linkText":"pakitsoq2006d13ch4.txt","urlDescription":"Data","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>notes"},{"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":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"calendar kiloyear before present","cvWhat":"age variable>age>gas age"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"gas chromatography","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":"corrected","cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"gas chromatography","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":null,"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 VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":"corrected","cvError":"one standard error","cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"gas chromatography","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":"corrected","cvError":"one standard error","cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":null,"cvDataType":"CLIMATE FORCING|ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"gas chromatography","cvSeasonality":null,"cvShortName":null,"cvUnit":"parts per billion","cvWhat":"chemical composition>compound>organic compound>hydrocarbon>alkane>n-alkane>methane"},{"cvAdditionalInfo":null,"cvDataType":"CLIMATE FORCING|ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"parts per billion","cvWhat":"chemical composition>compound>organic compound>hydrocarbon>alkane>n-alkane>methane"}]}],"dataTableName":"Pakitsoq d13C,CH4 Schaefer2006","dataTableNotes":"A total of 82 ice samples from Pakitsoq were analyzed for d13CH4 of enclosed air. The estimated range in age per sample is ca. 25 - 35 yr, which includes both sample thickness and gas age distribution due to diffusion and bubble enclosure. For replicate measurements (multiple ice samples of equal age) we report mean values with standard errors. For single measurements we show analytical precision as derived from the standard ice measurements during that measurement period. Several kinds of visible post-depositional features in the ice, such as fractures, layers or occlusions of dust, as well as certain bubble free bands, were associated with anomalously high values for both [CH4] and d13CH4, compared to surrounding unaffected samples. 11 samples were rejected from the final data set for this reason.\r\nPakitsoq age scale: The gas age scale used for assigning dates according to location in the sample profile is derived by comparison of three geochemical records from Pakitsoq and GISP2. Start and end points of prominent fluctuations in d15N, CH4, and d18Oice observed in Pakitsoq were matched with corresponding events recorded in GISP2.\r\nThe tie points are:\r\n(i) the start and peak of the end-of-YD d15N increase; \r\n(ii) the start and end of the Allerød – YD CH4 decline; \r\n(iii) the d18Oice minimum during the intra-Allerød cold period; and \r\n(iv) the d18Oice drop into the YD and rise into the PB. \r\nThe corresponding ages of the GISP2 age scale were corrected by -80 yr to match the date of 11,570 yrBP for the end-of-YD event derived from tree ring ages and assigned to the Pakitsoq inflection points as fixed ages. Between these dates, which are apart by 500 yr at the most, age was interpolated linearly.","earliestYear":12220,"earliestYearBP":12220,"earliestYearCE":-10270,"mostRecentYear":11360,"mostRecentYearBP":11360,"mostRecentYearCE":-9410,"species":[],"timeUnit":"cal yr BP"}],"siteName":"Pakitsoq outcrop"}],"studyCode":null,"studyName":"Pakitsoq outcrop - Methane Carbon Isotope Data","studyNotes":null,"version":"1.0","xmlId":"1254"}