What We Know about Climate Change

The vast majority of scientists agree that human activity has significantly increasedgreenhouse gases in the atmosphere--most dramatically since the 1970s. In February 2007 theIntergovernmental Panel on Climate Change found that global warming is "unequivocal" andthat human-produced carbon dioxide and other greenhouse gases are chiefly to blame, to a certaintyof more than 90 percent. Yet global warming skeptics and ill-informed elected officials continue todismiss this broad scientific consensus. In What We Know About Climate Change, MIT atmosphericscientist Kerry Emanuel outlines the basic science of global warming and how the current consensushas emerged. Although it is impossible to predict exactly when the most dramatic effects of globalwarming will be felt, he argues, we can be confident that we face real dangers. Emanuel, whose workwas widely cited in media coverage of Hurricane Katrina, warns that global warming will contributeto an increase in the intensity and power of hurricanes and flooding and more rapidly advancingdeserts. But just as our actions have created the looming crisis, so too might they avert it.Emanuel calls for urgent action to reduce greenhouse gases and criticizes the media for playing downthe dangers of global warming (and, in search of "balance," quoting extremists who denyits existence). An afterword by environmental policy experts Judith Layzer and William Moomawdiscusses how the United States could lead the way in the policy changes required to deal withglobal warming. Kerry Emanuel is Professor of Atmospheric Science in the Department of Earth,Atmospheric, and Planetary Science at MIT. He is the author of Divine Wind: The History and Scienceof Hurricanes and Atmospheric Convection. In May 2006 he was named one of Time magazine's "Time100: The People Who Shape Our World."

Kerry Emanuel is Professor of Atmospheric Science in the Department of Earth, Atmospheric, and Planetary Science at MIT. He is the author of Divine Wind: The History and Science of Hurricanes and Atmospheric Convection. In May 2006 he was named one of Time magazine's "Time 100: The People Who Shape Our World."