We examine the ability of an ensemble of 10 Regional Climate Models (RCMs), driven by ERA-Interim reanalysis, in skillfully reproducing key features of present-day precipitation and temperature (1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008) over West Africa. We explore a wide range of time scales spanning seasonal climatologies, annual cycles and interannual variability, and a number of spatial scales covering the Sahel, the Gulf of Guinea and the entire West Africa. We find that the RCMs show acceptable performance in simulating the spatial distribution of the main precipitation and temperature features. The occurrence of the West African Monsoon jump, the intensification and northward shift of the Saharan Heat Low (SHL), during the course of the year, are shown to be realistic in most RCMs. They also capture the mean annual cycle of precipitation and temperature, including, single and double-peaked rainy seasons, in terms of timing and amplitude over the homogeneous sub-regions. However, we should emphasize that the RCMs exhibit some biases, which vary considerably in both magnitude and spatial extent from model to model. The interannual variability of seasonal anomalies is best reproduced in temperature rather than precipitation. The ensemble mean considerably improves the skill of most of the individual RCMs. This highlights the importance of performing multi-model assessment in properly estimating the response of the West African climate to global warming at seasonal, annual and interannual time scales.

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We present an analysis of observed and simulated June–July–August (JJA) West African climate during the last 2 decades of the 20th and 21st centuries. The National Center for Atmospheric Research coupled atmosphere‐ocean climate system model (CSM) simulation is compared to long‐term observations and National Centers for Environmental Prediction reanalysis with an emphasis on the wet season during the late 20th century. While there are significant improvements in the simulation of the African Easterly Jet (AEJ) and African easterly waves relative to the uncoupled Community Climate Model, version 3, biases still exist. These biases are related to a poor simulation of the Azores high, which extends into eastern Europe, allowing for cold air advection into North Africa. There is also little improvement in the upper troposphere Tropical Easterly Jet in the CSM, which is too weak and does not extend westward over the Atlantic Ocean. In the late 21st century, JJA summer temperatures in West Africa have warmed 1.5°–2.5°C relative to the 1951–1980 period. Moreover, the Sahelian region is wetter in the late 21st century in association with an increase in atmospheric moisture, stronger meridional winds from the Gulf of Guinea, and a slightly stronger AEJ.

A three-day workshop at Howard University examined scientific and social issues associated with climate research in West Africa. Climate variability land-use, climate change, and capacity building were discussed.

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