Contemporary Climate Change of the African Monsoon Systems

Purpose of Review

Our current understanding of current climate change in the West African, East African, and Congo Basin monsoon systems is reviewed. The detection of observed trends, the analysis of the physical processes of change, and model projections are discussed.

Recent Findings

An increase in Sahel precipitation has been associated with a summer intensification and northward shift of the West African monsoon system as a response to amplified warming over the Sahara. Declines in the boreal spring rains over East Africa, and in spring and summer rains in the Congo Basin, are also reported in the literature but with less corroboration through physical analysis and model projections. Confident analysis and accurate simulation are hampered by a relative scarcity of observations in these regions.

Summary

The West African monsoon system is trending to bring more precipitation to the Sahel in summer, and some is delivered through increasingly intense rainfall events. It is not yet clear whether recent trends observed in the East African and Congo Basin monsoon systems can be expected to persist as the global climate continues to warm. We cannot expect these monsoon systems to change linearly through the twenty-first century because, as the ocean basins warm at different rates and with different distributions, different forcing factors may become dominant.