Climate of the Past www.clim-past.net 1814-9324 1814-9332 4 4 2008 10.5194/cp-4-333-2008 http://www.clim-past.net/4/333/2008/ http://www.clim-past.net/4/333/2008/cp-4-333-2008.html http://www.clim-past.net/4/333/2008/cp-4-333-2008.pdf 333 344 2008-12-06 Mid-depth South Atlantic Ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO₂ A. J. Dickson a.j.dickson@dunelm.org.uk M. J. Leng M. A. Maslin Environmental Change Research Centre, Department of Geography, University College London, Pearson Building, Gower Street, London, WC1E 6BT, UK NERC Isotope Geosciences Laboratory, British Geological Survey, Keyworth, Nottingham, NG12 5GG, UK School of Geography, University of Nottingham, Nottingham, NG7 2RD, UK A detailed record of benthic foraminifera carbon isotopes from the intermediate-depth South East Atlantic margin shows little glacial-interglacial variability between MIS-12 to MIS-10, suggesting that Northern Atlantic deepwaters consistently penetrated to at least 30° S. Millennial-scale increases in either the mass or flux of northern-sourced deepwaters over the core site occurred alongside reductions in Lower North Atlantic Deep Water recorded in North Atlantic sediment cores and show that the lower and intermediate limb of the Atlantic deepwater convective cell oscillated in anti-phase during previous glacial periods. 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