The effects of global warming are now a reality. Global warming played a major role in Hurricane Katrina, and its impact on agriculture and climate can jeopardize entire regional economic systems. Drawing on interviews with scientists and exploring the most up-to-date research, William Sweet examines what the United States can do to prevent further global warming. Rather than focusing on cutting oil consumption, which Sweet argues is expensive and not realistic, the United States should concentrate on drastically reducing its use of coal. Explaining in more practical terms, Sweet asks readers whether they'd rather pay $6 to $8 per gallon for gasoline or shut down the country's 100 dirtiest coal-based power plants. Coal-fired plants, which currently produce more than half of the electricity in the United States, emit dangerous amounts of carbon into the atmosphere. Sweet explains how a mixture of more environmentally sound technologies - wind turbines, natural gas, and nuclear reactors - can effectively replace coal plants, and how dramatic improvements in technology have made nuclear power cleaner, safer, and more efficient. Sweet cuts through the confusion and controversies that surround global warming, fossil fuels, and nuclear power. He offers portraits of scientists and explains the dramatic advances made by climate science. Sweet also addresses various political and economic issues associated with global warming, including the reality of reducing emissions from automobiles, the efficacy of taxing energy consumption, and the responsibility of the United States in reducing greenhouse gases.