{"NOAAStudyId":"21890","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":"2017-04-02","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-21890.xml","doi":null,"earliestYearBP":1277346,"earliestYearCE":-1275396,"entryId":"noaa-lake-21890","funding":[{"fundingAgency":"US National Science Foundation","fundingGrant":"EAR-902714"}],"investigators":"Johnson, T.C.; Werne, J.P.; Brown, E.T.; Abbott, A.; Berke, M.A.; Steinman, B.; Halbur, J.; Contreras, S.; Grosshuesch, S.; Deino, A.L.; Scholz, C.A.; Lyons, R.P.; Schouten, S.; Sinninghe Damsté, J.S.","mostRecentYearBP":361,"mostRecentYearCE":1589,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/21890","originalSource":null,"publication":[{"abstract":"African climate is generally considered to have evolved towards progressively drier conditions over the past few million years, with increased variability as glacial-interglacial change intensified worldwide. Palaeoclimate records derived mainly from northern Africa exhibit a 100,000-year (eccentricity) cycle overprinted on a pronounced 20,000-year (precession) beat, driven by orbital forcing of summer insolation, global ice volume and long-lived atmospheric greenhouse gases. Here we present a 1.3-million-year-long climate history from the Lake Malawi basin (10-14S in eastern Africa), which displays strong 100,000-year (eccentricity) cycles of temperature and rainfall following the Mid-Pleistocene Transition around 900,000 years ago. Interglacial periods were relatively warm and moist, while ice ages were cool and dry. The Malawi record shows limited evidence for precessional variability, which we attribute to the opposing effects of austral summer insolation and the temporal/spatial pattern of sea surface temperature in the Indian Ocean. The temperature history of the Malawi basin, at least for the past 500,000 years, strongly resembles past changes in atmospheric carbon dioxide and terrigenous dust flux in the tropical Pacific Ocean, but not in global ice volume. Climate in this sector of eastern Africa (unlike northern Africa) evolved from a predominantly arid environment with high-frequency variability to generally wetter conditions with more prolonged wet and dry intervals.","author":{"name":"T.C. Johnson, J.P. Werne, E.T. Brown, A. Abbott, M. Berke, B.A. Steinman, J. Halbur, S. Contreras, S. Grosshuesch, A. Deino, C.A. Scholz, R.P. Lyons, S. Schouten, and J.S. Sinninghe Damste"},"citation":"T.C. Johnson, J.P. Werne, E.T. Brown, A. Abbott, M. Berke, B.A. Steinman, J. Halbur, S. Contreras, S. Grosshuesch, A. Deino, C.A. Scholz, R.P. Lyons, S. Schouten, and J.S. Sinninghe Damste. 2016. A progressively wetter climate in southern East Africa over the past 1.3 million years. Nature, 537(7619), 220-224. doi: 10.1038/nature19065","edition":null,"identifier":{"id":"10.1038/nature19065","type":"doi","url":"http://dx.doi.org/10.1038/nature19065"},"issue":"7619","journal":"Nature","pages":"220-224","pubRank":"1","pubYear":2016,"reportNumber":null,"title":"A progressively wetter climate in southern East Africa over the past 1.3 million years","type":"publication","volume":"537"}],"reconstruction":"Y","scienceKeywords":null,"site":[{"NOAASiteId":"56660","geo":{"geoType":"Feature","geometry":{"coordinates":["-11.29389","34.43722"],"type":"POINT"},"properties":{"easternmostLongitude":"34.43722","maxElevationMeters":"500","minElevationMeters":"500","northernmostLatitude":"-11.29389","southernmostLatitude":"-11.29389","westernmostLongitude":"34.43722"}},"locationName":"Continent>Africa>Eastern Africa>Malawi","mappable":"Y","paleoData":[{"NOAADataTableId":"32924","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>geochemistry","earth science>paleoclimate>paleolimnology>reconstruction"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/malawi2016temp.txt","linkText":"Lake Malawi TEX86 Paleotemperature","urlDescription":"Formatted Text Data File","variables":[{"cvAdditionalInfo":"*indicates an assigned less extraneous LL drop in line with surrounding values","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Character","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":null,"cvWhat":"sampling metadata>notes"},{"cvAdditionalInfo":"meters below lake floor","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":"calendar year before present","cvWhat":"age variable>age"},{"cvAdditionalInfo":"C&S 2015; based on TEX86","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>organic compound index>glycerol dialkyl glycerol tetraether index","cvMethod":null,"cvSeasonality":"annual","cvShortName":null,"cvUnit":"degree Celsius","cvWhat":"earth system variable>temperature variable>temperature>lake water temperature>lake surface temperature"},{"cvAdditionalInfo":"meters relative to modern lake level","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"meter","cvWhat":"earth system variable>hydrographic variable>lake level"},{"cvAdditionalInfo":"meters relative to modern lake level;  Lake Level is not allowed to rise above present overflowing level","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":"corrected","cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"meter","cvWhat":"earth system variable>hydrographic variable>lake level"},{"cvAdditionalInfo":"C&S 2015; lapse-rate corrected; based on TEX86","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":"corrected","cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>organic compound index>glycerol dialkyl glycerol tetraether index","cvMethod":null,"cvSeasonality":"annual","cvShortName":null,"cvUnit":"degree Celsius","cvWhat":"earth system variable>temperature variable>temperature>lake water temperature>lake surface temperature"},{"cvAdditionalInfo":"C&S 2015; this is the basis for the tuning to LR04 with known ages as pointers; 5 point smoothed; based on TEX86","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":"smoothed","cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>organic compound index>glycerol dialkyl glycerol tetraether index","cvMethod":null,"cvSeasonality":"annual","cvShortName":null,"cvUnit":"degree Celsius","cvWhat":"earth system variable>temperature variable>temperature>lake water temperature>lake surface temperature"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"dimensionless","cvWhat":"chemical composition>compound>organic compound>organic compound index>tetraether index of 86 carbon atoms"},{"cvAdditionalInfo":"\" Lyons; First PC of f four sediment parameters: natural gamma radiation\"\",\"\" C/N ratio and δ13C of bulk organic matter\"\",\"\" and reflected colour of the core digital image. \"","cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"dimensionless","cvWhat":"statistical variable>multivariate eigenvector-based variable>principal component"}]},{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>geochemistry","earth science>paleoclimate>paleolimnology>reconstruction"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/malawi2016.xlsx","linkText":"Lake Malawi All Data","urlDescription":"Excel Data File","variables":[]}],"dataTableName":"Malawi2016temp","dataTableNotes":null,"earliestYear":1277346,"earliestYearBP":1277346,"earliestYearCE":-1275396,"mostRecentYear":361,"mostRecentYearBP":361,"mostRecentYearCE":1589,"species":[],"timeUnit":"cal yr BP"},{"NOAADataTableId":"32925","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>geochemistry","earth science>paleoclimate>paleolimnology>reconstruction"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/malawi2016temprs.txt","linkText":"Lake Malawi TEX86 Paleotemperature Rescaled","urlDescription":"Formatted Text Data File","variables":[{"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":"AgeScale rescaling of Corrected Temps using Pointers for pointers; based on TEX86","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>organic compound index>glycerol dialkyl glycerol tetraether index","cvMethod":null,"cvSeasonality":"annual","cvShortName":null,"cvUnit":"degree Celsius","cvWhat":"earth system variable>temperature variable>temperature>lake water temperature>lake surface temperature"},{"cvAdditionalInfo":"AgeScale rescaling of Crrcted Temps using Pointers for pointers; 5 point smooth; based on TEX86","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":"smoothed","cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>organic compound index>glycerol dialkyl glycerol tetraether index","cvMethod":null,"cvSeasonality":"annual","cvShortName":null,"cvUnit":"degree Celsius","cvWhat":"earth system variable>temperature variable>temperature>lake water temperature>lake surface temperature"}]},{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>geochemistry","earth science>paleoclimate>paleolimnology>reconstruction"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/malawi2016.xlsx","linkText":"Lake Malawi All Data","urlDescription":"Excel Data File","variables":[]}],"dataTableName":"Malawi2016temprs","dataTableNotes":null,"earliestYear":1277346,"earliestYearBP":1277346,"earliestYearCE":-1275396,"mostRecentYear":361,"mostRecentYearBP":361,"mostRecentYearCE":1589,"species":[],"timeUnit":"cal yr BP"},{"NOAADataTableId":"32926","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>geochemistry"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/malawi2016ca.txt","linkText":"Lake Malawi Calcium Data","urlDescription":"Formatted Text Data File","variables":[{"cvAdditionalInfo":"meters below lake floor","cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"meter","cvWhat":"depth variable>depth"},{"cvAdditionalInfo":"20 point smoothed; 1000 counts per minute","cvDataType":"PALEOLIMNOLOGY","cvDetail":"smoothed","cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"count per minute","cvWhat":"chemical composition>element or single-element molecule>calcium"}]}],"dataTableName":"Malawi2016Ca","dataTableNotes":null,"earliestYear":1277346,"earliestYearBP":1277346,"earliestYearCE":-1275396,"mostRecentYear":11210,"mostRecentYearBP":11210,"mostRecentYearCE":-9260,"species":[],"timeUnit":"cal yr BP"}],"siteName":"Lake Malawi, core GLAD7-MAL05-1"}],"studyCode":null,"studyName":"Lake Malawi, East Africa 1.3 Million Year TEX86 Paleotemperature","studyNotes":"TEX86 paleotemperature and Ca abundance (XRF) data from sediments collected in Lake Malawi, East Africa for the past 1.3 million years. 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