Lake Sibaya, South Africa 1800 Year Diatom Hydrological Data Stager, J.C.; Ryves, D.B.; King, C.D.; Madson, J.; Hazzard, M.; Neumann, F.H.; Maud, R. Stager, J.C. Ryves, D.B. King, C.D. Madson, J. Hazzard, M. Neumann, F.H. Maud, R. hydrology earth science/paleoclimate/climate reconstructions|paleolimnology (age,null,null,year Common Era,null,climate reconstructions|paleolimnology,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleolimnology (age,null,null,calendar year before present,null,climate reconstructions|paleolimnology,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleolimnology (electrical conductivity,diatom assemblage|lake water,null,microsiemens per centimeter,null,climate reconstructions|paleolimnology,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleolimnology (depth,null,null,centimeter,null,climate reconstructions|paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology (total planktic diatoms,null,null,percent,null,paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology earth science/paleoclimate/paleolimnology earth science/paleoclimate/paleolimnology (Lake Sibaya>LATITUDE -27.3333>LONGITUDE 32.6) The late Holocene history of the South African summer rainfall zone offers insights into the effects of climate on ecosystems and human societies, as well as into the accuracy of model projections of the future. However, some important aspects of this region's climatic history remain unresolved. Here we present new high-resolution diatom records representing hydrological fluctuations at Lake Sibaya, KwaZulu-Natal, during the last 1800 years. The cores were dated with 14C, 210Pb, 137Cs, and exotic pollen, and were sampled at increments of 1-22 years. A low stand ending ~AD 150 was followed by additional decadal to century-scale droughts, most notably ~AD 1540-1760, and several periods of markedly wetter conditions ~AD 220-290, AD 790-830, AD 1470-1540, and AD 1760-1860. The Medieval Climate Anomaly was generally wetter than average and the Little Ice Age was generally drier, but hydroclimate during both intervals was highly variable. These records confirm that local tree ring and stalagmite gray scale series represent rainfall variability, but they also show that widely cited stable isotope series from Makapansgat do not represent past climate as clearly. Because many interpretations of the climatic history of southern Africa have been influenced by those isotope data, we re-examine late Holocene precipitation variability in the summer rainfall zone, and also address model projections of future precipitation in the region. STUDY NOTES: Diatom record of core SIB-B collected from 16 m depth in the western arm of Lake Sibaya in 2004. Age model based on AMS dating of pollen fractions and bulk organic sediments, and stratigraphic matching with additional cores dated with lead-210, cesium-137, and exotic pollen (see manuscript for details). Higher percent planktonic diatoms ("diat-p%") taken to indicate qualitatively wetter conditions that would be likely to favor planktonic over benthic taxa due to higher lake level, suspended sediments in water column, and/or nutrient enrichment from enhanced runoff. Planktonic taxa: Aulacoseira, long Nitzschia, Synedra cf. acus and S. cf. tenera. Diatom-based conductivity estimates ("diat_cond") intended for qualitative use, with lower conductivity assumed to represent wetter climatic conditions. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Stager, J.C. Investigator : Ryves, D.B. Investigator : King, C.D. Investigator : Madson, J. Investigator : Hazzard, M. Investigator : Neumann, F.H. Investigator : Maud, R. 2013-06-27 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/14629 https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/africa/sibaya2013.txt https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/africa/sibaya2013.txt English https://www.ncdc.noaa.gov/paleo/study/14629 https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/africa/sibaya2013.txt J. Curt Stager, David B. Ryves, Christiaan King, Jerome Madson, Matthew Hazzard, Frank H. Neumann, Rodney Maud. 2013. Late Holocene precipitation variability in the summer rainfall region of South Africa. Quaternary Science Reviews, Vol. 67, pp. 105-120. DOI: 10.1016/j.quascirev.2013.01.022 START YEAR: 1802 cal yr BP * END YEAR: 60 cal yr BP 32.6 -27.3333 32.6 -27.3333