The Forgiving Air is the authoritative, up-to-date scientific guide to global change for which nonscientists have been waiting. Our planet's climate has been changing naturally since the Earth came into existence, but its nearly six billion inhabitants have become such a potent force that their influence on the global environment rivals that of Mother Nature. The ozone hole, the enhanced greenhouse effect, acid rain, air pollution in all its manifestations - these are the result of human activity, and now we have an unparalleled opportunity to understand why and how they occur. Highlighting the interrelatedness of human technology and environmental change, Somerville stresses the importance of an educated public in a world where the role of science is increasingly critical. He clarifies the pressing environmental issues and vividly covers related topics, from the chemical composition of the atmosphere to the specifics of computer modeling. The Forgiving Air is also rich in historical anecdotes and information about the scientists whose work has advanced our understanding. Somerville includes the fascinating story of the scientists who in 1974 predicted damage to the ozone layer from man-made chemicals. Their theoretical prediction, made a decade before the Antarctic ozone hole was discovered, caused intensive controversy in scientific circles and, especially, in the political world. At first the scientists were criticized and their work was belittled by the powerful and wealthy industry that made the offending chemicals. Today, however, it is clear that the science was right and that the ozone layer was in grave danger. One result has been an unprecedented series of international agreements to halt production of ozone-destroying chemicals. In 1995, the overwhelming importance of this research, which is detailed in The Forgiving Air, was recognized with the awarding of the Nobel Prize in Chemistry to three scientists who carried out pioneering studies in atmospheric ozone. If science has much to contribute to the making of wise public policy, it is ultimately the public and its representatives who must evaluate and act on scientists' recommendations. Thanks to Somerville's accessible, reader-friendly approach, we can be informed observers of these problems that crucially affect us all, and participants in their solution as well.