This book is a thorough introduction to climate science and global change. The author is a geologist who has spent much of his life investigating the climate of Earth from a time when it was warm and dinosaurs roamed the land, to today's changing climate. Bill Hay takes you on a journey to understand how the climate system works. He explores how humans are unintentionally conducting a grand uncontrolled experiment which is leading to unanticipated changes. We follow the twisting path of seemingly unrelated discoveries in physics, chemistry, biology, geology, and even mathematics to learn how they led to our present knowledge of how our planet works. He explains why the weather is becoming increasingly chaotic as our planet warms at a rate far faster than at any time in its geologic past. He speculates on possible future outcomes, and suggests that nature itself may make some unexpected course corrections. Although the book is written for the layman with little knowledge of science or mathematics, it includes information from many diverse fields to provide even those actively working in the field of climatology with a broader view of this developing drama. Experimenting on a Small Planet is a must read for anyone having more than a casual interest in global warming and climate change - one of the most important and challenging issues of our time. This new edition includes actual data from climate science into 2021. Numerous Powerpoint slides can be downloaded to allow lecturers and teachers to more effectively use the book as a basis for climate change education.