{"NOAAStudyId":"17841","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-17841.xml","doi":null,"earliestYearBP":3995,"earliestYearCE":-2045,"entryId":"noaa-icecore-17841","funding":[],"investigators":"Clausen, H.B.; Hammer, C.U.; Hvidberg, C.S.; Dahl-Jensen, D.; Steffensen, J.P.; Kipfstuhl, J.; Legrand, M.","mostRecentYearBP":-34,"mostRecentYearCE":1984,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/17841","originalSource":null,"publication":[{"abstract":"Since 1980 the electrical conductivity method (ECM) has been used to infer volcanic acid signals in Greenland ice cores. The method reveals the great majority of major volcanic eruptions, including several known from historic records. Subsequent ion chromatographic analyses of the acid volcanic layers show the chemical composition, i.e., the concentration of the volcanic acids H2SO4, HCI, and HF plus, e.g., the nonvolcanically derived HNO3. While ECM data are available from a large number of shallow depth Greenland ice cores, covering the past 500-1500 years, only the Greenland Ice Core Project (GRIP), Greenland Ice Sheet Project 2 (GISP2), and Dye 3 deep ice cores exist for a detailed comparative study of volcanic signals in Greenland ice cores representing several thousand years. Comparison of the volcanic signals registered in the GRIP and GISP2 cores will be presented elsewhere. The latter cores were augered 30 km apart and essentially represent the same atmospheric conditions such as temperature, snow accumulation, and chemical composition of the air. Here we present a comparison between the major volcanic signals over the past 4000 years in the GRIP core from central Greenland and the Dye 3 core from SE Greenland in order to investigate the depositional differences. Many of the major signals are detected in both cores, but some of the differences in the records can be used to infer the latitudinal band of some eruption sites. Furthermore, the influence of the amount of annual precipitation and glaciological postdepositional processes on the volcanic signals is discussed.","author":{"name":"Henrik B. Clausen, Claus U. Hammer, Christine S. Hvidberg, Dorthe Dahl‐Jensen, Jorgen P. Steffensen, Josef Kipfstuhl, Michel Legrand"},"citation":"Henrik B. Clausen, Claus U. Hammer, Christine S. Hvidberg, Dorthe Dahl‐Jensen, Jorgen P. Steffensen, Josef Kipfstuhl, Michel Legrand. 1997. A comparison of the volcanic records over the past 4000 years from the Greenland Ice Core Project and Dye 3 Greenland ice cores. Journal of Geophysical Research: Oceans, 102(C12), 26707-26723. doi: 10.1029/97JC00587","edition":null,"identifier":{"id":"10.1029/97JC00587","type":"doi","url":"http://dx.doi.org/10.1029/97JC00587"},"issue":"C12","journal":"Journal of Geophysical Research: Oceans","pages":"26707-26723","pubRank":"1","pubYear":1997,"reportNumber":null,"title":"A comparison of the volcanic records over the past 4000 years from the Greenland Ice Core Project and Dye 3 Greenland ice cores","type":"publication","volume":"102"}],"reconstruction":"N","scienceKeywords":null,"site":[{"NOAASiteId":"19973","geo":{"geoType":"Feature","geometry":{"coordinates":["72.58","-37.63"],"type":"POINT"},"properties":{"easternmostLongitude":"-37.63","maxElevationMeters":null,"minElevationMeters":null,"northernmostLatitude":"72.58","southernmostLatitude":"72.58","westernmostLongitude":"-37.63"}},"locationName":"Continent>North America>Greenland","mappable":"Y","paleoData":[{"NOAADataTableId":"28160","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>ice core>chemistry"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/chem/gripacid.txt","linkText":"GRIP Acidity","urlDescription":"Data File","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":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":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"year","cvWhat":"sampling metadata>number of samples"},{"cvAdditionalInfo":"microequivalent H+ per kilogram","cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>bulk ice","cvMethod":"direct current electrical conductivity measurement","cvSeasonality":null,"cvShortName":null,"cvUnit":"microequivalent per kilogram","cvWhat":"electrical property>electrical conductivity"},{"cvAdditionalInfo":"microequivalent H+ per kilogram; background","cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>bulk ice","cvMethod":"direct current electrical conductivity measurement","cvSeasonality":null,"cvShortName":null,"cvUnit":"microequivalent per kilogram","cvWhat":"electrical property>electrical conductivity"},{"cvAdditionalInfo":"microequivalent H+ per kilogram; maximum","cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>bulk ice","cvMethod":"direct current electrical conductivity measurement","cvSeasonality":null,"cvShortName":null,"cvUnit":"microequivalent per kilogram","cvWhat":"electrical property>electrical conductivity"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>bulk ice","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"kilogram per square kilometer","cvWhat":"chemical composition>compound>inorganic compound>sulfuric acid"},{"cvAdditionalInfo":null,"cvDataType":"ICE CORES","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>bulk ice","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"megaton","cvWhat":"chemical composition>compound>inorganic compound>sulfuric acid"}]}],"dataTableName":"GRIP1997acid","dataTableNotes":null,"earliestYear":3995,"earliestYearBP":3995,"earliestYearCE":-2045,"mostRecentYear":-34,"mostRecentYearBP":-34,"mostRecentYearCE":1984,"species":[],"timeUnit":"cal yr BP"}],"siteName":"GRIP"}],"studyCode":null,"studyName":"GRIP Ice Core 4000 Year Acidity Data","studyNotes":"This file contains the GRIP acidity record, as calculated from electrical conductivity measurements.","version":"1.0","xmlId":"15549"}