Projections of regional changes in surface air temperature and precipitation for the greater Nile River basin and northern Africa are presented. The probabilistic projections are obtained through a technique that combines projections of the MIT Integrated Global System Model with climate-change patterns of the Intergovernmental Panel on Climate Change. Overall, the most consistent response to climate policy is seen in the distributions of temperature change. For precipitation, the predominant climate stabilization response is to reduce the likelihood of modal change. To quantify risks of climate change, the study data can be vetted through a chain of impact models.