Regional Description – Africa and Madagascar

The palaeoclimate archives of tropical and marginal-tropical Africa and their interpretation are presented and critically discussed. The importance of the geomorphological, sedimentological, and pedological archives, in addition to Quaternary glaciations, for climate reconstruction is particularly emphasized and related to Quaternary marine environmental reconstructions. Quaternary climate and landscape change can be better reconstructed in Africa than in Latin America because (i) the African continent extends over 8000 km on either side of the equator to ca. 35° to the north and south, (ii) more than three-quarters of its area lie within the tropics (23.5° N and S), (iii) major mountain systems neither meridional (like the Andes of South America) nor latitudinal cross the continent, and (iv) the change from hot and humid tropical equatorial rainforest to the extremely arid desert is exemplary. The climatic and vegetation zones are interrupted in their latitudinal formation only in the mountains of East Africa. Early and middle Quaternary palaeoclimate archives (e.g. lake formations, moraines, speleothems, dunes) provide evidence of thermal and hygric climate fluctuations since the early Quaternary, which were much greater than the climate changes of the last glacial cycle. Cold phases are characterized by greater aridity in the lowlands. Warm phases (interglacials) were more humid; since Marine Isotope Stage 11, 400,000 years ago, warm-stage humidity decreased. The orbital and solar influence on large and small climate variations is documented by many different palaeoclimate archives. Terrestrial African palaeoclimate records document Arctic influence north of the equator and Antarctic influence in southern Africa. Climate modeling rarely considers the terrestrial palaeoclimate data of the African tropics. The extent to which climate influenced human cultures is shown using the example of the Sahara and East Africa.