ABSTRACT
Climatic records from equatorial eastern Africa and subtropical southern Africa have shown that both temperature and the amount of rainfall have varied over the past millennium. Moreover, the rainfall pattern in these two regions varied inversely over long periods of time. Droughts started abruptly and were of multidecadal to multicentennial length, and the changes in the hydrological budget were of large amplitude. Changing water resources in semiarid regions clearly must have had regional influences on both ecological and socioeconomic processes. Through a detailed analysis of the historical and paleoclimatic evidence from southern and eastern Africa covering the past millennium, one sees that, depending on their vulnerability, climatic variability can have an immense impact on societies, sometimes positive and sometimes disastrous.
