{"NOAAStudyId":"23690","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":"2018-03-23","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-23690.xml","doi":null,"earliestYearBP":1867200,"earliestYearCE":-1865250,"entryId":"noaa-lake-23690","funding":[{"fundingAgency":"US National Science Foundation","fundingGrant":"EAR 1123942, EAR 1338553, BCS 1241859"},{"fundingAgency":"International Continental Scientific Drilling Program (ICDP)","fundingGrant":null}],"investigators":"Lupien, R.L.; Russell, J.M.; Feibel, C.; Beck, C.; Castañeda, I.S.; Deino, A.L.; Cohen, A.S.","mostRecentYearBP":1378900,"mostRecentYearCE":-1376950,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/23690","originalSource":null,"publication":[{"abstract":"Climate is thought to play a critical role in human evolution; however, this hypothesis is difficult to test due to a lack of long, high-quality paleoclimate records from key hominin fossil locales. To address this issue, we analyzed organic geochemical indicators of climate in a drill core from West Turkana, Kenya that spans ~1.9-1.4 Ma, an interval that includes several important hominin evolutionary transitions. We analyzed the hydrogen isotopic composition of terrestrial plant waxes (dDwax) to reconstruct orbital-timescale changes in regional hydrology and their relationship with global climate forcings and the hominin fossil record. Our data indicate little change in the long-term mean hydroclimate during this interval, in contrast to inferred changes in the level of Lake Turkana, suggesting that lake level may be responding dominantly to deltaic progradation or tectonically-driven changes in basin configuration as opposed to hydroclimate. Time-series spectral analyses of the isotopic data reveal strong precession-band (21 kyr) periodicity, indicating that regional hydroclimate was strongly affected by changes in insolation. We observe an interval of particularly high-amplitude hydrologic variation at ~1.7 Ma, which occurs during a time of high orbital eccentricity hence large changes in processionally-driven insolation amplitude. This interval overlaps with multiple hominin species turnovers, the appearance of new stone tool technology, and hominin dispersal out of Africa, supporting the notion that climate variability played an important role in hominin evolution.","author":{"name":"R.L. Lupien, J.M. Russell, C. Feibel, C. Beck, I. Castañeda, A. Deino, A.S. Cohen"},"citation":"R.L. Lupien, J.M. Russell, C. Feibel, C. Beck, I. Castañeda, A. Deino, A.S. Cohen. 2018. A leaf wax biomarker record of early Pleistocene hydroclimate from West Turkana, Kenya. Quaternary Science Reviews, 186, 225-235. doi: 10.1016/j.quascirev.2018.03.012","edition":null,"identifier":{"id":"10.1016/j.quascirev.2018.03.012","type":"doi","url":"http://dx.doi.org/10.1016/j.quascirev.2018.03.012"},"issue":null,"journal":"Quaternary Science Reviews","pages":"225-235","pubRank":"1","pubYear":2018,"reportNumber":null,"title":"A leaf wax biomarker record of early Pleistocene hydroclimate from West Turkana, Kenya","type":"publication","volume":"186"}],"reconstruction":"Y","scienceKeywords":null,"site":[{"NOAASiteId":"57617","geo":{"geoType":"Feature","geometry":{"coordinates":["4.1097","35.8718"],"type":"POINT"},"properties":{"easternmostLongitude":"35.8718","maxElevationMeters":"404","minElevationMeters":"404","northernmostLatitude":"4.1097","southernmostLatitude":"4.1097","westernmostLongitude":"35.8718"}},"locationName":"Continent>Africa>Eastern Africa>Kenya","mappable":"Y","paleoData":[{"NOAADataTableId":"35514","coreLengthMeters":216,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>hydrogen isotopes","earth science>paleoclimate>paleolimnology>carbon isotopes"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/wturkana2018iso.txt","linkText":"West Turkana Leaf Wax Hydrogen and Carbon Isotope Data","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":"meter","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":"million years ago","cvWhat":"age variable>age"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"chemical composition>compound>organic compound>organooxygen compound>fatty acid>n-alkanoic acid>C28 n-alkanoic acid","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 2H"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"chemical composition>compound>organic compound>organooxygen compound>fatty acid>n-alkanoic acid>C28 n-alkanoic acid","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":"derived from a linear mixing model of the d13Cwax","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>isotope ratio>delta 13C","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"percent","cvWhat":"earth system variable>ecosystem variable>ecosystem quantity>C3 plants"},{"cvAdditionalInfo":"derived following methods in Konecky et al. 2016","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>precipitation","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 2H"}]}],"dataTableName":"WestTurkana2018iso","dataTableNotes":null,"earliestYear":1867200,"earliestYearBP":1867200,"earliestYearCE":-1865250,"mostRecentYear":1378900,"mostRecentYearBP":1378900,"mostRecentYearCE":-1376950,"species":[],"timeUnit":"cal yr BP"}],"siteName":"West Turkana HSPDP-WTK13-1A"}],"studyCode":null,"studyName":"West Turkana, Kenya 1.9-1.4 Ma Leaf Wax Hydrogen and Carbon Isotope Data","studyNotes":"Hydrogen and carbon isotopes of higher plant leaf waxes (dDwax and d13Cwax) from West Turkana, Kenya, covering ~1.9-1.4 Ma.","version":"1.0","xmlId":"21854"}