{"NOAAStudyId":"8663","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":"2010-01-01","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-8663.xml","doi":null,"earliestYearBP":8057,"earliestYearCE":-6107,"entryId":"noaa-lake-8663","funding":[],"investigators":"Clegg, B.F.; Hu, F.S.","mostRecentYearBP":-52,"mostRecentYearCE":2002,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/8663","originalSource":null,"publication":[{"abstract":"Understanding the ecological and socio-economic impacts of climatic warming requires knowledge of associated changes in moisture balance. Reconstructions of Holocene moisture-balance variation offer indispensible baseline information against which recent changes can be evaluated. In Alaska, little is known about variations in moisture balance during the middle- and late- Holocene. We analyzed Chara-stem encrustations in the sediments of Takahula Lake, south-central Brooks Range, for oxygen and carbon isotope composition to infer climatic change over the past 8000 years. To help constrain climatic interpretations of the sediment d18O record, we also analyzed water samples from Takahula and other lakes in the region for oxygen and hydrogen isotope composition. Results show that winter precipitation dominates the water balance of these lakes and that post-input evaporation is a key control of lake-water isotope composition of Takahula Lake. Stratigraphic patterns in Chara-d18O, supplemented by those in d13C and sediment lithology, reveal distinct changes in effective moisture (precipitation minus evaporation) over the past 8000 years. Effective moisture was relatively high from 8000 to 5000 cal. BP, with marked fluctuations between 6800 and 5000 cal. BP. It then decreased to reach a minimum around 4000 cal. BP and increased with fluctuations from 4000 to ~2500 cal. BP, followed by a decreasing trend toward the present that was interrupted by a wet Little Ice Age (centered at 400 cal. BP). Aridity during the 20th century was among the highest of the entire 8000-year record. The Chara-d18O values around 5600 cal. BP and around 400 cal. BP are up to 5ŋ lower than at present and ~2.3ŋ lower than that of the modern input water to the lake. These exceptionally low values suggest that factors other than effective moisture must have contributed to the pronounced variations in the Takahula Lake d18O record. These factors probably include increased winter precipitation related to the position and strength of the Aleutian Low, decreased temperatures, as well as increased lake-ice cover and associated reductions in evaporation. At millennial timescales, the temporal patterns of moisture-balance shifts at Takahula Lake are broadly coherent with those inferred from previous paleoclimate records from the region.","author":null,"citation":"Clegg, B.F., Hu, F.S. 2010. An oxygen-isotope record of Holocene climate change in the south-central Brooks Range, Alaska. Quaternary Science Reviews, 29, 928-939.","edition":null,"identifier":null,"issue":null,"journal":"Quaternary Science Reviews","pages":null,"pubRank":"1","pubYear":2010,"reportNumber":null,"title":"An oxygen-isotope record of Holocene climate change in the south-central Brooks Range, Alaska","type":"publication","volume":null}],"reconstruction":"N","scienceKeywords":null,"site":[{"NOAASiteId":"22960","geo":{"geoType":"Feature","geometry":{"coordinates":["67.35","-153.67"],"type":"POINT"},"properties":{"easternmostLongitude":"-153.67","maxElevationMeters":"275","minElevationMeters":"275","northernmostLatitude":"67.35","southernmostLatitude":"67.35","westernmostLongitude":"-153.67"}},"locationName":"Continent>North America>United States Of America>Alaska","mappable":"Y","paleoData":[{"NOAADataTableId":"12539","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>oxygen isotopes"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/northamerica/usa/alaska/takahula2010.xls","linkText":"takahula2010.xls","urlDescription":"Data","variables":[]},{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>oxygen isotopes"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/northamerica/usa/alaska/takahula2010.txt","linkText":"takahula2010.txt","urlDescription":"Data","variables":[{"cvAdditionalInfo":null,"cvDataType":"INSTRUMENTAL","cvDetail":null,"cvError":null,"cvFormat":"Character","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":null,"cvWhat":"sampling metadata>collection date"},{"cvAdditionalInfo":null,"cvDataType":"INSTRUMENTAL","cvDetail":null,"cvError":null,"cvFormat":"Character","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":null,"cvWhat":"sampling 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year before present","cvWhat":"age variable>age>age at sample end"},{"cvAdditionalInfo":"charophyte encrustation","cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>identified mineral>carbonate","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":"loss on ignition 950 degrees","cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":"loss on ignition","cvSeasonality":null,"cvShortName":null,"cvUnit":"gram per square centimeter per year","cvWhat":"geological material>identified mineral>carbonate>calcium carbonate"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"year Common Era","cvWhat":"age variable>age"},{"cvAdditionalInfo":"charophyte encrustation","cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>identified mineral>carbonate","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":null,"cvDataType":"INSTRUMENTAL","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>lake water","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VSMOW","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":null,"cvDataType":"INSTRUMENTAL","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>lake water","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VSMOW","cvWhat":"chemical composition>isotope>isotope ratio>delta 2H"},{"cvAdditionalInfo":null,"cvDataType":"INSTRUMENTAL","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"degree Fahrenheit","cvWhat":"earth system variable>temperature variable>temperature>air temperature"},{"cvAdditionalInfo":null,"cvDataType":"INSTRUMENTAL","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"degree Fahrenheit","cvWhat":"earth system variable>temperature variable>temperature>lake water temperature>lake surface temperature"},{"cvAdditionalInfo":null,"cvDataType":"INSTRUMENTAL","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"degree north","cvWhat":"sampling metadata>latitude"},{"cvAdditionalInfo":null,"cvDataType":"INSTRUMENTAL","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"degree east","cvWhat":"sampling metadata>longitude"}]}],"dataTableName":"Takahula Lake Core TAKAHULA","dataTableNotes":null,"earliestYear":8057,"earliestYearBP":8057,"earliestYearCE":-6107,"mostRecentYear":-52,"mostRecentYearBP":-52,"mostRecentYearCE":2002,"species":[],"timeUnit":"cal yr BP"}],"siteName":"Takahula Lake"}],"studyCode":null,"studyName":"Takahula Lake, Alaska 8,000 Year Stable Isotope Data","studyNotes":"Centennial resolution isotope and geochemical data for Takahula Lake, Alaska, for the past 8000 years, plus surface lake-water isotope data from other Brooks Range lakes. 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