Glacial to Holocene South African precipitation changes associated with Agulhas warm water transport.

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It is expected that Quaternary surface-ocean temperature variations around South Africa were pivotal for changes in rainfall over the continent. Therefore, SAPAC will study the importance of the warm Mosambique and Agulhas Current, as well as the cold Benguela Current, for last glacial to Holocene changes in South African precipitation. Planktonic foraminiferal oxygen isotope and minor element (Mg/Ca, Ba/Ca) records will be generated in combination with ketone unsaturation ratios for comparison with records of fluvial supply of land-derived material at decadal to centennial resolution off the major rivers of South Africa, the Orange, Limpopo, and Sambezi. These records should allow identification of temperature variability in the two different current systems, as well as changes in river runoff as a recorder of higher or lower precipitation during periods of rapid climate variability. The combination of new marine paleoenvironmental data sets from two cruises (M57-1 and M63- 1) will for the first time unravel the degree of correspondence in rapid climate variability between surface currents and between runoff variations of major rivers in eastern and western South Africa. Finally, this should allow identification of linkages between continental precipitation and subtropical ocean climate change, which is important basic knowledge required to better understand the role of rapid oceanic circulation changes under warm climate and cold conditions for the hydrological cycle over South Africa.