When Jeff Goodell first encountered the term geoengineering, he had a vague sense that it involved outlandish schemes to counteract global warming. As a journalist, he was deeply sceptical. But he was also intrigued. The planet was in trouble. Could geoengineers help?As Goodell shows in this bracing book, even if we could muster the political will for it, cutting greenhouse-gas emissions alone may not be enough to reduce the risk of climate catastrophe. This has led some scientists to pursue extreme solutions: huge contraptions that would suck CO2 from the air, machines that would brighten clouds and deflect sunlight away from the earth, even artificial volcanoes that would spray heat-reflecting particles into the atmosphere.Here, Goodell explores the scientific, political, financial, and moral aspects of geoengineering. Thoroughly reported and convincingly argued, How to Cool the Planet is a compelling tale of scientific hubris and technical daring. But it is also a thoughtful, even-handed look at a deeply complex and controversial issue. Its a book that will surely jump-start the next big debate about the future of life on earth.