Beyond Mitigation: Planning for Climate Change Adaptation

Abstract

Consider the floods, plagues, famines, and other calamities we can expect from climate change, and an apocalyptic prophecy might come to mind, perhaps rightfully so. An expert panel convened to assess risks from climate change put it this way in the 16 May 2009 issue of The Lancet: Should global mean temperatures rise an additional 5–6°C, “more than a billion people could be dispersed in environmental mass migration. . . . An additional 2 billion would be water stressed while billions more would face hunger or starvation. The risk of armed conflict would rise. Public health systems around the world would be damaged, some to the point of collapse.” Alarming scenarios like this have fueled efforts to lower heat-trapping greenhouse gas emissions and limit future impacts [see “Climate Change Abatement Strategies: Which Way Is the Wind Blowing?” p. A296 this issue]. But more recently, scientists have acknowledged that some degree of global warming is now inevitable. “Climate change models tell us that even if we blocked all emissions now, the amounts of greenhouse gases already in the atmosphere would raise global temperatures by an additional 2°C by 2100,” says Robert Corell, vice president of the John Heinz III Center for Science, Economics, and Environment, in Washington, DC. In light of this probability, Corell says, mitigation has begun sharing the global policy stage with a new challenge: how to adapt to climate change that is already under way.