{"NOAAStudyId":"6070","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":"2000-01-01","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-6070.xml","doi":null,"earliestYearBP":1070,"earliestYearCE":880,"entryId":"noaa-lake-6070","funding":[],"investigators":"Verschuren, D.; Laird, K.R.; Cumming, B.F.","mostRecentYearBP":-44,"mostRecentYearCE":1994,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/6070","originalSource":null,"publication":[{"abstract":"Knowledge of natural long-term rainfall variability is essential for water-resource and land-use management in sub-humid regions of the world. In tropical Africa, data relevant to determining this variability are scarce because of the lack of long instrumental climate records and the limited potential of standard high-resolution proxy records such as tree rings and ice cores. Here we present a decade-scale reconstruction of rainfall and drought in equatorial east Africa over the past 1,100 years, based on lake-level and salinity fluctuations of Lake Naivasha (Kenya) inferred from three different palaeolimnological proxies: sediment stratigraphy and the species compositions of fossil diatom and midge assemblages. Our data indicate that, over the past millennium, equatorial east Africa has alternated between contrasting climate conditions, with significantly drier climate than today during the 'Medieval Warm Period' (~AD 1000-1270) and a relatively wet climate during the 'Little Ice Age' (~AD 1270-1850) which was interrupted by three prolonged dry episodes. We also find strong chronological links between the reconstructed history of natural long-term rainfall variation and the pre-colonial cultural history of east Africa, highlighting the importance of a detailed knowledge of natural long-term rainfall fluctuations for sustainable socio-economic development.","author":null,"citation":"Verschuren, D., K.R. Laird, and B.F. Cumming. 2000. Rainfall and drought in equatorial east Africa during the past 1,100 years. Nature, 403, 410-414. doi:10.1038/35000179.","edition":null,"identifier":{"id":"10.1038/35000179","type":"doi","url":"http://dx.doi.org/10.1038/35000179"},"issue":null,"journal":"Nature","pages":null,"pubRank":"1","pubYear":2000,"reportNumber":null,"title":"Rainfall and drought in equatorial east Africa during the past 1,100 years","type":"publication","volume":null}],"reconstruction":"Y","scienceKeywords":null,"site":[{"NOAASiteId":"19890","geo":{"geoType":"Feature","geometry":{"coordinates":["-.7635","36.408"],"type":"POINT"},"properties":{"easternmostLongitude":"36.408","maxElevationMeters":null,"minElevationMeters":null,"northernmostLatitude":"-0.7635","southernmostLatitude":"-0.7635","westernmostLongitude":"36.408"}},"locationName":"Continent>Africa>Eastern Africa>Kenya","mappable":"Y","paleoData":[{"NOAADataTableId":"8109","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth 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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":"year Common Era","cvWhat":"age variable>age"}]},{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>reconstruction"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/naivasha_chironomidsalinity.xls","linkText":"naivasha_chironomidsalinity.xls","urlDescription":"Data","variables":[]},{"NOAAKeywords":["earth 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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":"year Common Era","cvWhat":"age variable>age"}]},{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>reconstruction"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/naivasha_diatomsalinity.xls","linkText":"naivasha_diatomsalinity.xls","urlDescription":"Data","variables":[]},{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>lake level"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/naivasha_lakelevel.txt","linkText":"naivasha_lakelevel.txt","urlDescription":"Data","variables":[{"cvAdditionalInfo":null,"cvDataType":"LAKE LEVELS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Character","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":null,"cvWhat":"sampling metadata>notes"},{"cvAdditionalInfo":null,"cvDataType":"LAKE LEVELS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"centimeter","cvWhat":"depth variable>depth"},{"cvAdditionalInfo":null,"cvDataType":"LAKE LEVELS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"year Common Era","cvWhat":"age variable>age"},{"cvAdditionalInfo":"water depth","cvDataType":"LAKE LEVELS|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"}]},{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>lake level"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/naivasha_lakelevel.xls","linkText":"naivasha_lakelevel.xls","urlDescription":"Data","variables":[]},{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>lake level"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/readme_verschuren2000.txt","linkText":"readme_verschuren2000.txt","urlDescription":"Readme","variables":[]}],"dataTableName":"Crescent Island Crater, Lake Naivasha Core CRESCENT","dataTableNotes":null,"earliestYear":1070,"earliestYearBP":1070,"earliestYearCE":880,"mostRecentYear":-44,"mostRecentYearBP":-44,"mostRecentYearCE":1994,"species":[],"timeUnit":"cal yr BP"}],"siteName":"Crescent Island Crater, Lake Naivasha"}],"studyCode":null,"studyName":"Rainfall and drought in equatorial east Africa during the past 1,100 years","studyNotes":null,"version":"1.0","xmlId":"676"}