''Earth's Climate: Past and Future'' works as either a nonmajors introduction to Earth system science or climate change, or as a majors/graduate-level overview of the processes and techniques in climate science. Written from a multidisciplinary perspective by a researcher/instructor in the field, the text summarizes the major lessons to be learned from 550 million years of climate changes, as a way of evaluating the climatological impact on and by humans in this century. The book also looks ahead to possible effects during the next several centuries of fossil fuel use.