LATE HOLOCENE NEOGLACIAL EPISODES IN SOUTHERN SOUTH-AMERICA AND SOUTHERN AFRICA - A COMPARISON

Palaeoenvironmental evidence from existing late-Holocene palaeoenvironmental sequences suggests that important atmospheric and oceanographic changes took place during the last 5000 years in southern South America and southern Africa. Several oscillations were contemporary with three well-known Neoglacial episodes that occurred between about 4500 and 4000 BP, between 3000 and 2000 BP and during the last 1000 years. The scale of change involved during these climatic episodes consisted of temperature departures of 1-2 degrees C, and sea-level oscillations of +/- 1-2 m. In at least two winter rainfall regions, an increase in precipitation was concomitant with most of these Neoglacial episodes. Minor northward latitudinal shifts of frontal systems, and relatively strong atmospheric circulation, were probably involved in the detected climatological trends. Minor, but significant, expansions of polar waters into the Humboldt and Benguela Currents are probably additional, and important, role players during these Neoglacial phases. Further establishment of more palaeoenvironmental sequences is needed in order to generate and test explanatory models.