Abstract

There is abundant evidence of wetter conditions in the Sahara during the early- to mid-Holocene, but a paucity of high-resolution spatial and temporal rainfall reconstructions, which has impeded the robust understanding of climate and archaeology. North of 28oN there is a particular lack of rainfall records, which limits testing of the processes controlling climate change in the sub-tropics. I will be sharing the results (from students in my group) of stalagmite records from inland, north-west Sahara – south of the Atlas Mountains – which demonstrate peak increased rainfall between 8.7-4.3 kyr BP. The location, timing, and oxygen isotopes of this stalagmite growth, when compared to other records, demonstrate that subtropical rainfall continues after the decline of the West African Monsoon. We propose that this rainfall is driven by an increased North-South interhemispheric temperature anomaly, shifting the ITCZ northwards and increasing tropical-plume rainfall in the South of Atlas region. This rainfall supported a significant increase in the region’s population during the Neolithic. Improved habitability and increased recharge to rivers flowing south through the Sahara will have facilitated connections, during a key period in the development of land use and animal production.