Timing and amplitude of the dessication of Sahel at the end of African Humid Period: Senegal case study

Abstract

Available archives of past environments and climates in Senegal are relatively limited in number and concentrated in “Niayes” coastal area. The review of available data for the 6 ka–2 ka period presented here provides a major contribution, revealing that the end of AHP occurred in two successive stages. A first dry event was dated at 4.5 ka. However, its impact was considerably attenuated in this region due to specific conditions on the Atlantic coast, compared to other areas of the Sahel. Depending on the site, gallery forests were either minimally affected or, conversely, replaced by wooded grasslands. After a brief return to humid conditions, the Niayes region experienced dessication at 2.5 ka, with the drying up of water bodies and dramatic disruption of the gallery forests.