{"NOAAStudyId":"25311","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":"2018-10-01","dataPublisher":"NOAA","dataType":"PALEOLIMNOLOGY","dataTypeInformation":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/lake","difMetadataLink":"http://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-lake-25311.xml","doi":null,"earliestYearBP":7730,"earliestYearCE":-5780,"entryId":"noaa-lake-25311","funding":[{"fundingAgency":"US National Science Foundation","fundingGrant":"1108306, 1107411"}],"investigators":"Lasher, G.E.; Axford, Y.; McFarlin, J.M.; Kelly, M.A.; Osterberg, E.; Berkelhammer, M.B.","mostRecentYearBP":-64,"mostRecentYearCE":2014,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/25311","originalSource":null,"publication":[{"abstract":"Reconstructions of Holocene lake water isotopic composition based upon subfossil aquatic organic material offer new insights into Arctic climate. We present quantitative estimates of warmth during the Holocene Thermal Maximum in northwest Greenland, inferred from oxygen isotopes of chironomid head capsules and aquatic moss preserved in lake sediments. d18O values of chironomids from surface sediments of multiple Greenland lakes indicate that these subfossil remains record the d18O values of the lake water in which they grow. Our lake water d18O reconstruction is supported by downcore agreement with d18O values in aquatic moss and chironomid remains. d18O of both organic materials from Secret Lake decrease after 4 ka (ka = thousands of years ago) by 3 permil into the Neoglacial. We argue that lake water at Secret Lake primarily reflects precipitation d18O values, which is strongly correlated with air temperature in NW Greenland, and that this signal is biased towards summer and early autumn conditions. Other factors may have influenced Secret Lake d18O values through the Holocene, including evaporation of lake water and changing seasonality and source of precipitation. The maximum early Holocene summer and early autumn-biased temperature anomaly at Secret Lake is 2.5-4C warmer than present from 7.7 (the beginning of our record) to ~6 ka. The maximum late Holocene cold anomaly (which includes the Little Ice Age) is 1.5-3C colder than present. These ranges of possible temperature anomalies reflect uncertainty in the d18O - temperature relationship for precipitation at the study site through the Holocene.","author":{"name":"G. Everett Lasher, Yarrow Axford, Jamie M. McFarlin, Meredith A. Kelly, Erich C.Osterberg, Max B. Berkelhammer"},"citation":"G. Everett Lasher, Yarrow Axford, Jamie M. McFarlin, Meredith A. Kelly, Erich C.Osterberg, Max B. Berkelhammer. 2017. Holocene temperatures and isotopes of precipitation in Northwest Greenland recorded in lacustrine organic materials. Quaternary Science Reviews, 170, 44-55. doi: 10.1016/j.quascirev.2017.06.016","edition":null,"identifier":{"id":"10.1016/j.quascirev.2017.06.016","type":"doi","url":"http://dx.doi.org/10.1016/j.quascirev.2017.06.016"},"issue":null,"journal":"Quaternary Science Reviews","pages":"44-55","pubRank":"1","pubYear":2017,"reportNumber":null,"title":"Holocene temperatures and isotopes of precipitation in Northwest Greenland recorded in lacustrine organic materials","type":"publication","volume":"170"}],"reconstruction":"Y","scienceKeywords":null,"site":[{"NOAASiteId":"57738","geo":{"geoType":"Feature","geometry":{"coordinates":["76.58021","-68.65907"],"type":"POINT"},"properties":{"easternmostLongitude":"-68.65907","maxElevationMeters":"250","minElevationMeters":"250","northernmostLatitude":"76.58021","southernmostLatitude":"76.58021","westernmostLongitude":"-68.65907"}},"locationName":"Continent>North America>Greenland","mappable":"Y","paleoData":[{"NOAADataTableId":"37133","coreLengthMeters":1,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>oxygen isotopes","earth science>paleoclimate>paleolimnology>reconstruction"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/greenland/secret2017.txt","linkText":"Secret Lake Chironomid d18O and Inferred Temperature","urlDescription":"NOAA Template File","variables":[{"cvAdditionalInfo":null,"cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"centimeter","cvWhat":"depth variable>depth"},{"cvAdditionalInfo":null,"cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"calendar year before present","cvWhat":"age variable>age"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>organism>midge","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VSMOW","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":"sample_d18O_chiron - 22.4 per mil (methods outlined in Lasher et al. 2017","cvDataType":"PALEOLIMNOLOGY","cvDetail":"differenced","cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>lake water","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VSMOW","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":"3 point moving average of sample_age values","cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"calendar year before present","cvWhat":"age variable>age"},{"cvAdditionalInfo":"3 point moving average of sample_d18O_chiron values","cvDataType":"PALEOLIMNOLOGY","cvDetail":"averaged","cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>organism>midge","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VSMOW","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":"3 point moving average of sample_inferred_lw_d18O values","cvDataType":"PALEOLIMNOLOGY","cvDetail":"averaged","cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>lake water","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VSMOW","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":"Global temp-d18O: reconstruction_d18O relative to depth 0 (age -64 cal yr BP) / 0.67","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":"anomalized","cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>isotope ratio>delta 18O","cvMethod":"regression analysis","cvSeasonality":"annual","cvShortName":null,"cvUnit":"degree Celsius","cvWhat":"earth system variable>temperature variable>temperature"},{"cvAdditionalInfo":"Thule annual temp-d18O: reconstruction_d18O relative to depth 0 (age -64 cal yr BP) / 0.44","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":"anomalized","cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>isotope ratio>delta 18O","cvMethod":"regression analysis","cvSeasonality":"annual","cvShortName":null,"cvUnit":"degree Celsius","cvWhat":"earth system variable>temperature variable>maximum temperature"},{"cvAdditionalInfo":"Thule summer temp-d18O: reconstruction_d18O relative to depth 0 (age -64 cal yr BP) / 0.59","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":"anomalized","cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>isotope ratio>delta 18O","cvMethod":"regression analysis","cvSeasonality":"3-month period>Jun-Aug","cvShortName":null,"cvUnit":"degree Celsius","cvWhat":"earth system variable>temperature variable>temperature"}]}],"dataTableName":"14-SEC-N1","dataTableNotes":null,"earliestYear":7730,"earliestYearBP":7730,"earliestYearCE":-5780,"mostRecentYear":-64,"mostRecentYearBP":-64,"mostRecentYearCE":2014,"species":[],"timeUnit":"cal yr BP"}],"siteName":"Secret Lake"}],"studyCode":null,"studyName":"Secret Lake, NW Greenland Holocene Chironomid d18O and Inferred Temperature","studyNotes":"Oxygen isotope record measured on chironomid head capsule macrofossils, with inferred temperatures","version":"1.0","xmlId":"23494"}