noaa-lake-5454 eng; USA utf8 dataset NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact NCEI Contact Information Information for contacts at NCEI. information pointOfContact NOAA World Data Service for Paleoclimatology Data Center Contact 828-271-4800 303-497-6513 325 Broadway, E/NE31 Boulder CO 80305-3328 USA paleo@noaa.gov pointOfContact 2024-05-02 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) NOAA/WDS Paleoclimatology - Lake Bosumtwi, Ghana Late Quaternary Magnetic Mineral Data 2007-01-01 publication doi:10.25921/149q-tg68 noaa-lake-5454 NCEI DSI 1200_02 NCEI DSI 1200_01 Peck, J.A. originator Peck, J.A. author Green, R.R. originator Green, R.R. author Shanahan, T.M. originator Shanahan, T.M. author King, J.W. originator King, J.W. author Overpeck, J.T. originator Overpeck, J.T. author Scholz, C.A. originator Scholz, C.A. author NOAA National Centers for Environmental Information publisher tableDigital This archived Paleoclimatology Study is available from the NOAA National Centers for Environmental Information (NCEI), under the World Data Service (WDS) for Paleoclimatology. The associated NCEI study type is Lake. The data include parameters of paleolimnology with a geographic location of Ghana, Western Africa. The time period coverage is from 26655 to -32 in calendar years before present (BP). See metadata information for parameter and study location details. Please cite this study when using the data. Records of past climate and environment derived from lake sediment records. Parameter keywords describe what was measured in this dataset. Additional summary information can be found in the abstracts of papers listed in the dataset citations. completed NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact NCEI Contact Information Information for contacts at NCEI. information pointOfContact NOAA World Data Service for Paleoclimatology Data Center Contact 828-271-4800 303-497-6513 325 Broadway, E/NE31 Boulder CO 80305-3328 USA paleo@noaa.gov pointOfContact https://www.ncei.noaa.gov/pub/data/paleo/webimages/pc-default-lake.png Paleoclimatology - Lake PNG Earth Science > Climate Indicators > Paleoclimate Indicators > Ocean/Lake Records theme Global Change Master Directory (GCMD) Science Keywords 2025 revision 22 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 22. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology earth science > paleoclimate > paleolimnology > magnetic susceptibility earth science > paleoclimate > paleolimnology > physical properties earth science > paleoclimate > paleolimnology > geochemistry theme Global Change Master Directory (GCMD) Science Keywords 2025 revision 22 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 22. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian What: sample identification; Material: null What: depth; Material: null What: depth; Material: null What: age; Material: null What: age; Material: null What: saturation isothermal remanent magnetization/saturation isothermal magnetization; Material: sediment What: coercivity; Material: sediment What: saturation isothermal remanent magnetization; Material: sediment What: coercivity of remanence/coercivity; Material: sediment What: S-ratio; Material: sediment What: coercivity of remanence; Material: sediment What: saturation isothermal remanent magnetization/initial magnetization slope; Material: sediment What: saturation isothermal magnetization; Material: sediment What: organic matter; Material: sediment What: age; Material: null What: age; Material: null What: volume magnetic susceptibility; Material: sediment What: initial magnetization slope; Material: sediment theme Paleoenvironmental Standard Terms (PaST) Thesaurus NOAA National Centers for Environmental Information https://www.ncei.noaa.gov/products/paleoclimatology/paleoenvironmental-standard-terms-thesaurus PaST Thesaurus information publisher Continent > Africa > Western Africa > Ghana > Lake Bosumtwi > LATITUDE 6.5 > LONGITUDE -1.4167 place DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce dataCentre Global Change Master Directory (GCMD) Data Center Keywords 2025 revision 22 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 22. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian otherRestrictions Cite as: Peck, J.A.; Green, R.R.; Shanahan, T.M.; King, J.W.; Overpeck, J.T.; Scholz, C.A. (2007-01-01): NOAA/WDS Paleoclimatology - Lake Bosumtwi, Ghana Late Quaternary Magnetic Mineral Data. [indicate subset used]. NOAA National Centers for Environmental Information. https://doi.org/10.25921/149q-tg68. Accessed [date]. otherRestrictions Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives. otherRestrictions Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose otherRestrictions None otherRestrictions 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. A magnetic mineral record of Late Quaternary tropical climate variability from Lake Bosumtwi, Ghana 2004 publication Peck, J.A., R.R. Green, T. Shanahan, J.W. King, J.T. Overpeck, C.A. Scholz author Palaeogeography, Palaeoclimatology, Palaeoecology publisher https://doi.org/10.1016/j.palaeo.2004.08.003 HTTPS Web Browser Associated Reference published 2004 Peck, J.A., R.R. Green, T. Shanahan, J.W. King, J.T. Overpeck, C.A. Scholz, 2004: A magnetic mineral record of Late Quaternary tropical climate variability from Lake Bosumtwi, Ghana. Palaeogeography, Palaeoclimatology, Palaeoecology, 215, 37-57, 10.1016/j.palaeo.2004.08.003 information crossReference sciencePaper eng; USA geoscientificInformation Date Range: 26655 cal yr BP to -32 cal yr BP; -1.4167 -1.4167 6.5 6.5 Study Coordinates 6.5 -1.4167 -24705 1982 STUDY NOTES: Lake Bosumtwi, Ghana (6°30'N, 1°25'W, 99m. elev.). In June, 2000, 19 piston cores were extracted from Lake Bosumtwi. Eight short piston cores (1N-8N), ranging from 108 to 134 cm in length, were used to capture the sediment-water interface. These cores were supplemented by two freeze cores obtained from the deepest portion of the lake. The remaining 11 longer cores, ranging from 5.5 to 10.9 m in length, did not preserve the sediment-water interface, but were correlated with the shorter cores using well-defined marker bands. Physical property logging of whole core volumetric magnetic susceptibility and gammaray attenuation (an estimation of wet bulk density) was conducted on the piston cores using an automated Geotek multisensor core logger. ABSTRACT SUPPLIED BY ORIGINATOR: We report magnetic hysteresis results from sediment cores obtained from Lake Bosumtwi, Ghana. As a hydrologically closed basin, the water budget of Lake Bosumtwi is extremely sensitive to changes in the precipitation/evapotranspiration balance. Lake Bosumtwi lies in the path of the seasonal migration of the intertropical convergence zone (ITCZ); hence, the lake is ideally situated to study monsoon variability in West Africa. Five distinctive magnetic mineral zones (A-E) were identified in the 11-m-long sediment cores that span the last 26,000 calendar years. Prior to 12 calendar (cal) ka, low concentrations of multidomain, high-coercivity magnetic minerals are present. Three prominent shifts towards very high concentrations of high-coercivity iron sulfide (greigite) magnetic minerals are centered at 12,470, 17,290, and 22,600 calendar years during the last glacial period (magnetic zones D1-3). Between 12 and 3.2 cal ka, there is an abrupt shift to moderately high concentrations of mixed multidomain and single-domain, low-coercivity minerals and an organic-rich sapropel lithology. Since 3.2 cal ka, the magnetic mineral parameters reveal a shift to increased amounts of high-coercivity magnetic minerals. These magnetic mineral zones document tropical climate variability on a variety of temporal scales. Glacial age sediments have a high-coercivity magnetic mineralogy due to increased aeolian dust transport from the Sahel to Lake Bosumtwi as well as postdepositional reductive diagenesis. During the last glacial period, the increased strength of Harmattan and North African continental trade winds, the southward depression of the ITCZ, and weakened summer monsoon strength resulted in increased regional aridity and greater dust flux out of Sahel source regions. The greigite-bearing D magnetic zones correspond to brief lowstands in the level of Lake Bosumtwi and likely represent periods of intensified aridity in West Africa. The D magnetic zones closely resemble the timing and duration of Heinrich events and suggest a hemispheric-scale climatic coupling between the tropics and poles. The well-documented African humid period (AHP) is characterized by abrupt shifts in magnetic parameters between 12 and 3.2 cal ka. Dust flux to Lake Bosumtwi is inferred to be very low during this humid interval due to the strengthening of the summer monsoon. Since 3.2 cal ka, the magnetic mineral parameters suggest increased aridity as compared to the AHP. This work demonstrates that the magnetic properties of Lake Bosumtwi sediment are a sensitive recorder of abrupt climate change of global significance. NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact NCEI Contact Information Information for contacts at NCEI. information distributor In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media. Contact NCEI for other distribution options and instructions. Native Format(s) https://doi.org/10.25921/149q-tg68 HTTPS Landing Page Metadata Landing Page NCEI landing page with general information and links to access the data. information https://www.ncei.noaa.gov/access/paleo-search/study/5454 HTTPS Web Browser NOAA Study Page Study page with data access information. search https://www.ncei.noaa.gov/products/paleoclimatology/lake HTTPS Information NCEI Lake Page General information for this data type. information https://www.ncei.noaa.gov/pub/data/paleo/paleolimnology/africa/bosumtwi2004-piston-noaa.txt HTTPS Download NCEI Direct Download Direct download links for dataset files. download https://www.ncei.noaa.gov/pub/data/paleo/paleolimnology/africa/bosumtwi2004-org-noaa.txt HTTPS Download NCEI Direct Download Direct download links for dataset files. download https://www.ncei.noaa.gov/pub/data/paleo/paleolimnology/africa/bosumtwi2004-magsus-noaa.txt HTTPS Download NCEI Direct Download Direct download links for dataset files. download https://www.ncei.noaa.gov/pub/data/paleo/paleolimnology/africa/bosumtwi2004-freeze-noaa.txt HTTPS Download NCEI Direct Download Direct download links for dataset files. download asNeeded This ISO metadata record was translated from DIF metadata using dif-9x-to-iso-19115-2.xsl Version: 2022-06-21