So the Sahel, where people really die when drought happens, could be wetter in a globally warmed world, according to new research by a team led by Reindert J. Haarsma of the Royal Netherlands Meteorological Institute:

We hypothesize that through this mechanism greenhouse warming will cause an increase in Sahel rainfall, because the warming is expected to be more prominent over the summer continents than over the oceans. This has been confirmed using an ensemble of 62 coupled model runs forced with a business as usual scenario. The ensemble mean increase in Sahel rainfall between 1980 and 2080 is about 1–2 mm day−1 (25–50 percent) during July–September, thereby strongly reducing the probability of prolonged droughts.