Climate Change Conflicts
BenIAM in comments points to a report on Post-Conflict Environmental Assessment in Sudan by the United Nations Environment Programme. Chapter 4 (pdf), recommendable also for its pictures, says:
The scale of historical climate change as recorded in Northern Darfur is almost unprecedented: the reduction in rainfall has turned millions of hectares of already marginal semi-desert grazing land into desert. The impact of climate change is considered to be directly related to the conflict in the region, as desertification has added significantly to the stress on the livelihoods of pastoralist societies, forcing them to move south to find pasture.
That seems to be the central point of what the conflict in Darfur and neighboring Chad is about. Millions of people are moving away from land that turned to desert and conflict naturally arises when they ‘invade’ other people’s land. Economic shocks caused by a lack of a rainfall are the major cause (pdf) of civil wars in sub- Saharan Africa.