Widespread food shortages in the developing world resulting from changing weather patterns; disease outbreaks; mass migration as people abandon farms because of failing crops; populations fleeing coastal areas because of sea level rises. Each of these is a potential byproduct of climate change.

Whether they will all come to pass, and the extent of the likely damage to the climate, are matters of scientific and political debate. But even if only a few of these predictions come true, the world can expect to see much greater political and economic instability in already hard-hit regions.