The temporal dynamics of crop yield responses to climate change in East Africa

There is general consensus that the impacts of climate change on agriculture will add significantly to the development challenges of ensuring food security and reducing poverty, particularly in Africa. It is often assumed that these changes will influence agriculture at a broad scale, such that regional or country recommendations might cope with the results. To refute this we use high-resolution methods to generate characteristic daily weather data for a combination of different SRES (Special Report on Emissions Scenarios) and Global Circulation Models to drive detailed simulation models of maize and bean crops. For the East African region, we find that there are considerable differences in crop response and that there is substantial spatial and temporal variation in this response. The analysis suggests that the impacts on households will be neither linear nor constant through time. The results argue strongly against the idea of spatially contiguous and large “development domains” for identifying and implementing adaptation options. Rather, they underline the crucial importance of localized, community-based efforts to increase local adaptive capacity and take advantage of changes that may lead to increased crop and livestock productivity and to buffer the situations where increased stresses are likely to occur