Researcher Hans Joachim Schellnhuber’s group published reports that suggest that even modest climate change might drastically affect the living conditions of billions of people, whether through water scarcity, crop shortages or extremes of weather.
Regions most at risk from water scarcity include parts of the southern United States, the Mediterranean and the Middle East. By contrast, India, tropical Africa and high latitudes in the Northern Hemisphere can expect to receive more water in a warming world. In addition, drought conditions are likely to become more frequent and severe in some parts of South America, western and central Europe, central Africa and Australia, another project team reports.

Flood risk is less clear-cut, but river-flow simulations from global hydrology and land-surface models did show an increase in flood hazard in more than half of the world.