{"NOAAStudyId":"15615","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":"2013-12-05","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-15615.xml","doi":null,"earliestYearBP":108159,"earliestYearCE":-106209,"entryId":"noaa-icecore-15615","funding":[],"investigators":"Rasmussen, S.O.; Abbott, P.M.; Blunier, T.; Bourne, A.J.; Brook, E.J.; Buchardt, S.L.; Buizert, C.; Chappellaz, J.A.; Clausen, H.B.; Cook, E.; Dahl-Jensen, D.; Davies, S.M.; Guillevic, M.; Kipfstuhl, S.; Laepple, T.; Seierstad, I.K.; Severinghaus, J.; Steffensen, J.P.; Stowasser, C.; Svensson, A.M.; Vallelonga, P.; Vinther, B.M.; Wilhelms, F.; Winstrup, M.","mostRecentYearBP":0,"mostRecentYearCE":1950,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/15615","originalSource":null,"publication":[{"abstract":"A stratigraphy-based chronology for the North Greenland Eemian Ice Drilling (NEEM) ice core has been derived by transferring the annual layer counted Greenland Ice Core Chronology 2005 (GICC05) and its model extension (GICC05modelext) from the NGRIP core to the NEEM core using 787 match points of mainly volcanic origin identified in the electrical conductivity measurement (ECM) and dielectrical profiling (DEP) records. Tephra horizons found in both the NEEM and NGRIP ice cores are used to test the matching based on ECM and DEP and provide five additional horizons used for the timescale transfer.\r\n\r\nA thinning function reflecting the accumulated strain along the core has been determined using a Dansgaard-Johnsen flow model and an isotope-dependent accumulation rate parameterization. Flow parameters are determined from Monte Carlo analysis constrained by the observed depth-age horizons.\r\n\r\nIn order to construct a chronology for the gas phase, the ice age-gas age difference (D-age) has been reconstructed using a coupled firn densification-heat diffusion model. Temperature and accumulation inputs to the D-age model, initially derived from the water isotope proxies, have been adjusted to optimize the fit to timing constraints from d15N of nitrogen and high-resolution methane data during the abrupt onset of Greenland interstadials.\r\n\r\nThe ice and gas chronologies and the corresponding thinning function represent the first chronology for the NEEM core, named GICC05modelext-NEEM-1. Based on both the flow and firn modelling results, the accumulation history for the NEEM site has been reconstructed. Together, the timescale and accumulation reconstruction provide the necessary basis for further analysis of the records from NEEM.\r\n","author":{"name":"Rasmussen, S.O., Abbott, P.M., Blunier, T., Bourne, A.J., Brook, E., Buchardt, S.L., Buizert, C., Chappellaz, J., Clausen, H.B., Cook, E., Dahl-Jensen, D., Davies, S.M., Guillevic, M., Kipfstuhl, S., Laepple, T., Seierstad, I.K., Severinghaus, J.P., Steffensen, J.P., Stowasser, C., Svensson, A., Vallelonga, P., Vinther, B.M., Wilhelms, F., and Winstrup, M."},"citation":"Rasmussen, S.O., Abbott, P.M., Blunier, T., Bourne, A.J., Brook, E., Buchardt, S.L., Buizert, C., Chappellaz, J., Clausen, H.B., Cook, E., Dahl-Jensen, D., Davies, S.M., Guillevic, M., Kipfstuhl, S., Laepple, T., Seierstad, I.K., Severinghaus, J.P., Steffensen, J.P., Stowasser, C., Svensson, A., Vallelonga, P., Vinther, B.M., Wilhelms, F., and Winstrup, M. 2013. A first chronology for the North Greenland Eemian Ice Drilling (NEEM) ice core. Climate of the Past, 9(6), 2713-2730. doi: 10.5194/cp-9-2713-2013","edition":null,"identifier":{"id":"10.5194/cp-9-2713-2013","type":"doi","url":"http://dx.doi.org/10.5194/cp-9-2713-2013"},"issue":"6","journal":"Climate of the Past","pages":"2713-2730","pubRank":"1","pubYear":2013,"reportNumber":null,"title":"A first chronology for the North Greenland Eemian Ice Drilling (NEEM) ice core","type":"publication","volume":"9"}],"reconstruction":"N","scienceKeywords":["Dansgaard-Oeschger cycles"],"site":[{"NOAASiteId":"53299","geo":{"geoType":"Feature","geometry":{"coordinates":["77.45","-51.06"],"type":"POINT"},"properties":{"easternmostLongitude":"-51.06","maxElevationMeters":null,"minElevationMeters":null,"northernmostLatitude":"77.45","southernmostLatitude":"77.45","westernmostLongitude":"-51.06"}},"locationName":"Continent>North America>Greenland","mappable":"Y","paleoData":[{"NOAADataTableId":"25599","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>ice core>age control"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/ngrip/ngrip2013ecm.txt","linkText":"ngrip2013ecm.txt","urlDescription":"Data","variables":[{"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":"hydrologic material>bulk ice","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"microequivalent per kilogram","cvWhat":"chemical composition>element or single-element molecule>hydrogen>hydrogen ions"}]},{"NOAAKeywords":["earth science>paleoclimate>ice core>age control"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/ngrip/ngrip2013dep.txt","linkText":"ngrip2013dep.txt","urlDescription":"Data","variables":[{"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":"hydrologic material>bulk ice","cvMethod":"dielectric profiling","cvSeasonality":null,"cvShortName":null,"cvUnit":"siemens per meter","cvWhat":"electrical property>electrical conductivity"}]},{"NOAAKeywords":["earth science>paleoclimate>ice core>age control"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/neem/2013-12-05GICC05modelext-NEEM-1.xls","linkText":"2013-12-05GICC05modelext-NEEM-1.xls","urlDescription":"Data","variables":[]},{"NOAAKeywords":["earth science>paleoclimate>ice core>age control"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/neem/lsce-neem-d15n-mis3-guillevic2013.txt","linkText":"lsce-neem-d15n-mis3-guillevic2013.txt","urlDescription":"Data","variables":[{"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":"averaged","cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil AIR","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"}]},{"NOAAKeywords":["earth science>paleoclimate>ice core>age control"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/neem/neem2013dep.txt","linkText":"neem2013dep.txt","urlDescription":"Data","variables":[{"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":"hydrologic material>bulk ice","cvMethod":"dielectric profiling","cvSeasonality":null,"cvShortName":null,"cvUnit":"siemens per meter","cvWhat":"electrical property>electrical conductivity"}]},{"NOAAKeywords":["earth science>paleoclimate>ice core>age control"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/neem/neem2013ecm.txt","linkText":"neem2013ecm.txt","urlDescription":"Data","variables":[{"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":"hydrologic material>bulk ice","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"microequivalent per kilogram","cvWhat":"chemical composition>element or single-element molecule>hydrogen>hydrogen ions"}]},{"NOAAKeywords":["earth science>paleoclimate>ice core>age control"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/neem/2013-12-05GICC05modelext-NEEM-1.txt","linkText":"2013-12-05GICC05modelext-NEEM-1.txt","urlDescription":"Data","variables":[{"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":"present defined as 2000 A.D.","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"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>bulk ice","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"meter per year","cvWhat":"formation property>formation rate>accumulation rate"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":"one standard deviation","cvFormat":"Numeric","cvMaterial":"hydrologic material>bulk ice","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"meter per year","cvWhat":"formation property>formation rate>accumulation rate"}]}],"dataTableName":"NEEM-1-2013","dataTableNotes":null,"earliestYear":108159,"earliestYearBP":108159,"earliestYearCE":-106209,"mostRecentYear":0,"mostRecentYearBP":0,"mostRecentYearCE":1950,"species":[],"timeUnit":"cal yr BP"}],"siteName":"NEEM"}],"studyCode":null,"studyName":"NEEM Ice Core NEEM-1 Time Scale","studyNotes":"NEEM-1 ice core time scale with match points to NGRIP1 and NGRIP2 ice cores and the GICC05 timescale.  Also included are NEEM and NGRIP DEP and ECM data, and NEEM d15N.  Original Excel file contains the ice and gas time scales and all the info needed to construct it: match points, delta age calculations, flow model results, and accumulation rate results.  A text version contains the same information, and additional text files contain the NEEM and NGRIP DEP, ECM, and d15N data series, presented in WDC Paleo text format.  ","version":"1.0","xmlId":"13418"}