noaa-lake-8657 Lake Bosumtwi 3,000 Year Laminated Sediment d18O and XRF Data 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. Lake Bosumtwi 3,000 Year Laminated Sediment d18O and XRF Data 2009-08-01 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/8657 Investigator T. Shanahan Investigator J.T. Overpeck Investigator K.J. Anchukaitis Investigator J.W. Beck Investigator J.E. Cole Investigator D.L. Dettman Investigator J.A. Peck Investigator C.A. Scholz Investigator J.W. King earth science paleoclimate paleolimnology manganese,sediment,null,count per second,null,paleolimnology,null,x-ray fluorescence spectroscopy,N,null earth science paleoclimate paleolimnology iron,sediment,null,count per second,null,paleolimnology,null,x-ray fluorescence spectroscopy,N,null earth science paleoclimate paleolimnology aluminum,sediment,null,count per second,null,paleolimnology,null,x-ray fluorescence spectroscopy,N,null earth science paleoclimate paleolimnology principal component,null,null,dimensionless,null,paleolimnology,null,null,N,principal component #2 of element concentration earth science paleoclimate climate reconstructions|paleolimnology silicon,sediment,null,count per second,null,climate reconstructions|paleolimnology,smoothed,x-ray fluorescence spectroscopy,N,smoothed 10 year average earth science paleoclimate paleolimnology principal component,null,null,dimensionless,null,paleolimnology,detrended,null,N,PC#1 of element concentration; detrended using 600 year 50% spline earth science paleoclimate paleolimnology delta 18O,carbonate,null,per mil VPDB,null,paleolimnology,smoothed,isotope ratio mass spectrometry,N,smoothed 5 year average earth science paleoclimate paleolimnology calcium,sediment,null,count per second,null,paleolimnology,null,x-ray fluorescence spectroscopy,N,null earth science paleoclimate paleolimnology age,null,null,year Common Era,null,paleolimnology,null,null,N,null earth science paleoclimate paleolimnology potassium,sediment,null,count per second,null,paleolimnology,null,x-ray fluorescence spectroscopy,N,null earth science paleoclimate paleolimnology principal component,null,null,dimensionless,null,paleolimnology,null,null,N,principal component #1 of element concentration earth science paleoclimate paleolimnology titanium,sediment,null,count per second,null,paleolimnology,null,x-ray fluorescence spectroscopy,N,null earth science paleoclimate paleolimnology age,null,null,calendar year before present,null,paleolimnology,null,null,N,null earth science paleoclimate paleolimnology delta 18O,carbonate,null,per mil VPDB,null,paleolimnology,null,isotope ratio mass spectrometry,N,null earth science paleoclimate paleolimnology silicon,sediment,null,count per second,null,paleolimnology,null,x-ray fluorescence spectroscopy,N,null earth science paleoclimate paleolimnology geochemistry geoscientificInformation 2559 cal yr BP -53 cal yr BP Complete 6.5 6.5 -1.4167 -1.4167 99 99 Continent Africa Western Africa Ghana Lake Bosumtwi>LATITUDE 6.5>LONGITUDE -1.4167 None 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. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII 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.

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. STUDY NOTES: 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.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/africa/bosumtwi2009.xls GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/africa/bosumtwi2009.txt USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11