Spatio-temporal evolution of the West African monsoon during the last deglaciation

On the basis of a multi‐proxy data set from the Gulf of Guinea (eastern equatorial Atlantic) we reconstruct the spatio‐temporal evolution of the West African monsoon (WAM) and present evidence for a decoupling between latitudinal shifts of the rain belt and WAM intensification. The onset of deglacial monsoon invigoration at ∼16,600 years before present lagged northward migration of a weak rainfall zone by ∼2800 years. Conversely, during the Younger Dryas (YD) time interval, WAM precipitation was severely reduced but we find no evidence for a large‐scale retreat of the rainfall front. This observation is not in agreement with the hypothesis of a large‐scale shift of the intertropical convergence zone south of the tropical WAM region during the YD. Our results can be better reconciled with the newly emerging concept of a strong influence of Tropical Easterly and African Easterly Jets on modern WAM. Key Points Spatio‐temporal evolution of regional climate Our results challenges existting notion about west african monsoon evolution Our finding is consistent with emerging picture of modern climate of West Africa