noaa-lake-17347 Lake Bosumtwi, Ghana Sediment Age Models Shanahan, T.M.; Peck, J.A.; McKay, N.P.; Heil, C.W.; King, J.E.; Forman, S.L.; Hoffmann, D.L.; Richards, D.A.; Overpeck, J.T.; Scholz, C.A. Lake Bosumtwi, Ghana Sediment Age Models 2014-10-19 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/17347 Investigator Shanahan, T.M. Investigator J.A. Peck Investigator N.P. McKay Investigator C.W. Heil Investigator J.E. King Investigator S.L. Forman Investigator D.L. Hoffmann Investigator D.A. Richards Investigator J.T. Overpeck Investigator C.A. Scholz earth science paleoclimate paleolimnology age control geoscientificInformation 500000 cal yr BP 0 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

325 Broadway, E/NE31

Boulder CO 80305-3328 USA online ASCII Timothy M. Shanahan, John A. Peck, Nicholas McKay, Clifford W. Heil Jr., John King, Steven L. Forman, Dirk L. Hoffmann, David A. Richards, Jonathan T. Overpeck, Christopher Scholz 2013 Quaternary Geochronology 15 47-60 10.1016/j.quageo.2012.12.001 http://www.sciencedirect.com/science/article/pii/S1871101412001872 Timothy M. Shanahan, J. Warren Beck, Jonathan T. Overpeck, Nicholas P. McKay, Jeffrey S. Pigati, John A. Peck, Christopher A. Scholz, Clifford W. Heil Jr., John King 2012 Palaeogeography, Palaeoclimatology, Palaeoecology 361-362 49-60 10.1016/j.palaeo.2012.08.001 http://www.sciencedirect.com/science/article/pii/S0031018212004415

The continuous 300-m long drill cores obtained from Lake Bosumtwi, Ghana represent one of the longest, continuous lacustrine sequences obtained from an extant lake, and contain an unprecedented record of late Quaternary climate change in West Africa. However, one of the main challenges associated with generating long paleoclimate time series from terrestrial records such as this is the development of accurate age-depth relationships because unlike marine records, lacustrine sequences cannot be tuned to global ice volume records via d18O stratigraphy. The Lake Bosumtwi record thus offers an excellent case study for examining the potential and the challenges associated with different geochronological techniques in lacustrine systems. In the present study, we use a combination of radiocarbon, optically stimulated luminescence and U-series dating and paleomagnetic excursions to generate a chronology for the upper ca. 150 ka of sedimentation at Lake Bosumtwi and employ a Bayesian approach to generate a continuous age-depth relationship. The resultant chronology is then used to test the effectiveness of tuning of an environmental magnetic proxy for dust against a well-dated record of high latitude dust. Our approach highlights the advantages of using multiple dating approaches, and the dangers of relying on too few age constraints when dating long sedimentary sequences. However, the excellent agreement between the different approaches over most of the record suggest that well-constrained age-depth models for long sedimentary sequences can be produced using this combination of approaches. Furthermore, our data provide support for extending the chronology beyond the limit of radiocarbon, U-series and OSL in the future using paleomagnetic excursions/reversals and tuning against well-dated high latitude paleoclimate records. STUDY NOTES: Lake Bosumtwi, Ghana sediment age models derived from 4 methods: Radiocarbon, U-series, Paleomagnetism, and Optically Stimulated Luminescence (OSL).

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/africa/bosumtwi2013age.txt Data File; Lake Bosumtwi Sediment Age Models USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11