Climate change will significantly alter West African summer monsoon precipitation. By the end of the century, a zonal contrast will emerge, with increased precipitation in the central Sahel and decreased precipitation in the western Sahel. This contrast arises from opposing fast and slow responses to greenhouse gas increases. The fast response, driven by enhanced radiative warming, dominates initially. The study highlights that mitigation strategies can effectively reduce climate change's impact on Sahel precipitation within decades by dampening this fast response. This timescale decomposition also improves understanding of climate model prediction uncertainties in Africa.

Paul-Arthur Monerie, Benjamin Pohl, Marco Gaetani