noaa-lakelevel-17677 The seismic-stratigraphic record of lake-level fluctuations in Lake Challa: hydrological stability and change in equatorial East-Africa over the last 140 kyr Moernaut, J.; Verschuren, D.; Charlet, F; Kristen, I.; Fagot, M.; De Batist, M. The seismic-stratigraphic record of lake-level fluctuations in Lake Challa: hydrological stability and change in equatorial East-Africa over the last 140 kyr 2014-12-19 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/17677 Investigator J. Moernaut Investigator D. Verschuren Investigator F Charlet Investigator I. Kristen Investigator M. Fagot Investigator M. De Batist earth science paleoclimate lake levels|paleolimnology lake level,null,null,dimensionless,null,lake levels|paleolimnology,null,null,N,values used in plot earth science paleoclimate lake levels|paleolimnology notes,null,null,null,null,lake levels|paleolimnology,null,null,C,null earth science paleoclimate lake levels|paleolimnology age at sample end,null,null,calendar kiloyear before present,null,lake levels|paleolimnology,null,null,N,maximum age earth science paleoclimate lake levels|paleolimnology age at sample start,null,null,calendar kiloyear before present,null,lake levels|paleolimnology,null,null,N,maximum age earth science paleoclimate lake levels|paleolimnology lake level,null,null,dimensionless,null,lake levels|paleolimnology,null,null,C,null earth science paleoclimate lake levels|paleolimnology age at sample start,null,null,calendar kiloyear before present,null,lake levels|paleolimnology,null,null,N,null earth science paleoclimate lake levels|paleolimnology age at sample start,null,null,calendar kiloyear before present,null,lake levels|paleolimnology,null,null,N,minimum age earth science paleoclimate lake levels|paleolimnology age at sample end,null,null,calendar kiloyear before present,null,lake levels|paleolimnology,null,null,N,minimum age earth science paleoclimate lake levels|paleolimnology age at sample end,null,null,calendar kiloyear before present,null,lake levels|paleolimnology,null,null,N,null earth science paleoclimate lake levels geoscientificInformation Monsoon 127710 cal yr BP -60 cal yr BP Complete -3.3167 -3.3167 37.7 37.7 880 880 Continent Africa Eastern Africa Kenya Lake Challa>LATITUDE -3.3167>LONGITUDE 37.7 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 Moernaut, J.; Verschuren, D.; Charlet, F.; Kristen, I.;Fagot, M.; De Batist, M. 2010 Earth and Planetary Science Letters 290 (1-2) 214-223

Seismic-reflection data from crater lake Challa(Mt. Kilimanjaro, equatorial East Africa) reveal a ~210-m thick sedimentary infill containing distinct seismic-stratigraphic signatures of late-Quaternary lake-level fluctuations. Extrapolation of a well-constrained age model on the cored upper part of the sequence suggests that these lake-level fluctuations represent a detailed and continuous record of moisture-balance variation inequatorial East Africa over the last 140 kyr. This record indicates that the most severe aridity occurred during peak Penultimate glaciation immediately before ~128 kyr BP (coeval with Heinrich event 11) and during a Last Interglacial ‘megadrought’ period between ~114 and ~97 kyr BP; in comparison, Last Glacial Maximum (LGM) aridity was modest. It was preceded by ~75 000 years of relatively stable and moist climate conditions interrupted by eleven short-lived dry spells, five of which match the timing of Heinrich events 2 to 6. Climate history near the East African equator reflects variation in the precessional forcing of monsoon rainfall modulated by orbital eccentricity, but precession-driven moisture fluctuations were less extreme than those observed in northern and southern tropical Africa. The near-continuous moist climate from ~97 to 20.5 kyr BP recorded in the Lake Challa record contrasts with the trend towards greater aridity after ~70 kyr BP documented in equatorial West Africa. This long period of moist glacial climate and a short, relatively modest LGM drought can be attributed to greater independence of western Indian Ocean monsoon dynamics from northern high-latitude glaciation than those in the tropical Atlantic Ocean. This rather persistent moist glacial climate regime may have helped maintain high biodiversity in the tropical forest ecosystems of the Eastern Arc mountains in Tanzania. STUDY NOTES: Lake Challa 130kyr lake-level reconstruction. Reconstruction based on the succession of draped (highstand) and focused (lowstand) units in seismic stratigraphy, and landslide deposits (lowstands); see Moernaut et al. (2010), Earth and Planetary Science Letters 290, 214-223. Contact: Dirk Verschuren, dirk.verschuren@UGent.be

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/lakelevels/africa/eastafrica/moernaut2010-lakechalla.txt Lake Levels Data; moernaut2010-lakechalla.txt USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11