"Most books and articles about climate change focus on two important questions. First, what will growing emissions of greenhouse gases (GHGs) mean for the climate over the coming decades? By how much will temperatures increase and sea levels rise? And what will be the economic and social damage resulting from these changes? Second, what should be done to avert climate change? By how much and how rapidly should GHG emissions be reduced? Is a carbon tax the best policy tool, and if so, how large should the tax be? But two additional questions are equally important. First, while we might agree on what should be done, we must ask what will be done to avert climate change. Is it realistic to expect worldwide emissions to fall rapidly enough to prevent severe climate change? Second, if we conclude it is not realistic, so that higher temperatures and rising sea levels are likely, what should we do? What actions should we take now to reduce the likely impact of climate change? These questions are the focus of this book. I explain how and why there is considerable uncertainty over what might happen. We might be lucky and experience only mild climate change, but counting on good luck is not smart policy. I show that given the economic and political realities, it is simply not realistic to expect the GHG emission reductions needed to avert substantial global warming. We should therefore invest now in adaptation to reduce the possible impacts of warming, and I show how that can be done"--