Middle to Late Holocene Changes in Tropical Africa and Other Continents: Paleomonsoon and Sea Surface Temperature Variations

  • Jean Maley
Conference paper
Part of the NATO ASI Series book series (volume 49)

Abstract

In tropical Africa the transition from the Middle Holocene (ca. 7000 to 3800 years BP) climate to the Late Holocene (ca. 3800 BP to present) was abrupt and marked by major paleoenvironmental shifts. The sediment and lake level changes in forested equatorial belt of tropical Africa, in the Sahel and Sahara and in the tropical areas of other continents (India, Australia and South America) are interpreted in terms of paleoclimate based on comparison made between the African paleodata and some present-day rainfall anomalies. These anomalies are associated with sea surface temperature (SST) variations and are closely linked to the intensity of upwelling and trade winds. We conclude that the abrupt changes in the tropical belt at the beginning of the Late Holocene could be related to the variation of the Zonal Walker Circulation, mainly the El Niño-Southern Oscillation (ENSO. The SST opposition between northern and southern Atlantic Ocean has a major influence on climatic changes in tropical Africa. Moreover, the predicted global warming during the next century could lead in tropical Africa to climate induced large rain forest destructions.

Keywords

Cretaceous Hull Charcoal Gravel Hunt 

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© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Jean Maley
    • 1
  1. 1.Paléoenvironnements & Palynologie (CNRS/ISEM & ORSTOM)Université de Montpellier 2MontpellierFrance

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