{"NOAAStudyId":"8657","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":"2009-08-01","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-8657.xml","doi":null,"earliestYearBP":2559,"earliestYearCE":-609,"entryId":"noaa-lake-8657","funding":[],"investigators":"Shanahan, T.; Overpeck, J.T.; Anchukaitis, K.J.; Beck, J.W.; Cole, J.E.; Dettman, D.L.; Peck, J.A.; Scholz, C.A.; King, J.W.","mostRecentYearBP":-53,"mostRecentYearCE":2003,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/8657","originalSource":null,"publication":[{"abstract":"Although persistent drought in West Africa is well documented from the instrumental record and has been primarily attributed to changing Atlantic sea surface temperatures, little is known about the length, severity, and origin of drought before the 20th century. We combinedgeomorphic, isotopic, and geochemical evidence from the sediments of Lake Bosumtwi, Ghana, to reconstruct natural variability in the African monsoon over the past three millennia. We find that intervals of severe drought lasting for periods ranging from decades to centuries are characteristic of the monsoon and are linked to natural variations in Atlantic temperatures. Thus the severe drought of recent decades is not anomalous in the context of the past three millennia, indicating that the monsoon is capable of longer and more severe future droughts.","author":null,"citation":"Shanahan, T., Overpeck, J.T., Anchukaitis, K.J., Beck, J.W., Cole, J.E., Dettman, D.L., Peck, J.A., Scholz, C.A., King, J.W. 2009. Atlantic Forcing of Persistent Drought in West Africa. Science, 324.","edition":null,"identifier":null,"issue":null,"journal":"Science","pages":null,"pubRank":"1","pubYear":2009,"reportNumber":null,"title":"Atlantic Forcing of Persistent Drought in West Africa","type":"publication","volume":null}],"reconstruction":"Y","scienceKeywords":null,"site":[{"NOAASiteId":"8890","geo":{"geoType":"Feature","geometry":{"coordinates":["6.5","-1.4167"],"type":"POINT"},"properties":{"easternmostLongitude":"-1.4167","maxElevationMeters":"99","minElevationMeters":"99","northernmostLatitude":"6.5","southernmostLatitude":"6.5","westernmostLongitude":"-1.4167"}},"locationName":"Continent>Africa>Western Africa>Ghana","mappable":"Y","paleoData":[{"NOAADataTableId":"12532","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>geochemistry"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/africa/bosumtwi2009.txt","linkText":"bosumtwi2009.txt","urlDescription":"Data","variables":[{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":"x-ray fluorescence spectroscopy","cvSeasonality":null,"cvShortName":null,"cvUnit":"count per second","cvWhat":"chemical composition>element or single-element molecule>potassium"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":"x-ray fluorescence spectroscopy","cvSeasonality":null,"cvShortName":null,"cvUnit":"count per second","cvWhat":"chemical composition>element or single-element molecule>calcium"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":"x-ray fluorescence spectroscopy","cvSeasonality":null,"cvShortName":null,"cvUnit":"count per second","cvWhat":"chemical composition>element or single-element molecule>titanium"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":"x-ray fluorescence spectroscopy","cvSeasonality":null,"cvShortName":null,"cvUnit":"count per second","cvWhat":"chemical composition>element or single-element molecule>manganese"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":"x-ray fluorescence spectroscopy","cvSeasonality":null,"cvShortName":null,"cvUnit":"count per second","cvWhat":"chemical composition>element or single-element molecule>iron"},{"cvAdditionalInfo":"principal component #1 of element concentration","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"},{"cvAdditionalInfo":"principal component #2 of element concentration","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"},{"cvAdditionalInfo":"PC#1 of element concentration; detrended using 600 year 50% spline","cvDataType":"PALEOLIMNOLOGY","cvDetail":"detrended","cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"dimensionless","cvWhat":"statistical variable>multivariate eigenvector-based variable>principal component"},{"cvAdditionalInfo":"smoothed 10 year average","cvDataType":"CLIMATE RECONSTRUCTIONS|PALEOLIMNOLOGY","cvDetail":"smoothed","cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":"x-ray fluorescence spectroscopy","cvSeasonality":null,"cvShortName":null,"cvUnit":"count per second","cvWhat":"chemical composition>element or single-element molecule>silicon"},{"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":null,"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":null,"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":"smoothed 5 year average","cvDataType":"PALEOLIMNOLOGY","cvDetail":"smoothed","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":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":"x-ray fluorescence spectroscopy","cvSeasonality":null,"cvShortName":null,"cvUnit":"count per second","cvWhat":"chemical composition>element or single-element molecule>aluminum"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":"x-ray fluorescence spectroscopy","cvSeasonality":null,"cvShortName":null,"cvUnit":"count per second","cvWhat":"chemical composition>element or single-element molecule>silicon"}]},{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>geochemistry"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/africa/bosumtwi2009.xls","linkText":"bosumtwi2009.xls","urlDescription":"Data","variables":[]}],"dataTableName":"Lake Bosumtwi BOSUMTW d18O XRF","dataTableNotes":null,"earliestYear":2559,"earliestYearBP":2559,"earliestYearCE":-609,"mostRecentYear":-53,"mostRecentYearBP":-53,"mostRecentYearCE":2003,"species":[],"timeUnit":"cal yr BP"}],"siteName":"Lake Bosumtwi"}],"studyCode":null,"studyName":"Lake Bosumtwi 3,000 Year Laminated Sediment d18O and XRF Data","studyNotes":"Oxygen isotopes of authigenic lake carbonate, and micro-x-ray fluorescence (m-XRF) scanning of major element concentrations (Al, Si, K, Ti, Fe, and Ca) in laminated sediments from Lake Bosumtwi.","version":"1.0","xmlId":"2277"}