Climate Change Refugees (extended version)
Human-induced climate and hydrologic change is likely to make many parts of the world uninhabitable, or at least uneconomic. Even if there are some "winners" from climate change—perhaps farmers in high-latitude farm regions where the growing season will be extended by warmer temperatures—there will also be large numbers of undeniable losers. Over the course of a few decades, if not sooner, hundreds of millions of people may be compelled to relocate because of environmental pressures.
To a significant extent, water will be the most important determinant of these population movements. Dramatic changes in the relationship between water and society will be widespread, as emphasized in the new report from Working Group II of the Inter-Governmental Panel on Climate Change. These shifts may include rising sea levels, stronger tropical cyclones, the loss of soil moisture under higher temperatures, more intense precipitation and flooding, more frequent droughts, the melting of glaciers and the changing seasonality of snowmelt. Combined with the human-induced depletion of groundwater sources by pumping, and the extensive pollution of rivers and lakes, mass migrations may be unavoidable.