Implications of climate change and anthropogenic activity for the water security of West African river basins

West Africa experiences some of the most extreme climatic variability anywhere in the world. The 1970s and 1980s saw drought triggering regional-scale famine; in more recent years, a recovery in rainfall totals has led to devastating flood events, such as those seen across the region in 2009. Knowledge of the potential impact of future climate and anthropogenic change on water resources, food production and ecosystem services for highly vulnerable populations is essential to water planners, managers and policy makers. The GWAVA water resources model provides key information on the potential scale of water deficits and/or surpluses across West Africa for the present and future climate using 29 Global Circulation Models from the CMIP5 ensemble. Areas of concern are highlighted, and mitigating strategies explored, such as supplementary irrigation or use of more drought-tolerant crops, as sustainable ways in which to support climate-compatible development in the region. Analysis considers the role of current policy on the allocation of water resources in West Africa, and how a changing future climate may impact these policies and the region’s growing population.