Drylands are highly sensitive to changes in precipitation and evapotranspiration. Potential evapotranspiration  is projected to increase in all regions globally, under all RCPs, as a result of increasing temperatures and surface water vapour deficit . Simulations based on coupled land surface, energy, and water and vegetation models in the Central Sahel showed a strong response of the water budget. Under +2℃ and +4℃ warming scenarios, decreased evapotranspiration, runoff and drainage were found for all scenarios, except those with the highest precipitation .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report