A key concept this textbook explores is the reign of chaos, the actual facts about chaotic weather during the dry, cool periods known as ice ages. It is no accident that the entire history of human civilization took place within a wet / warm period. In geological terms these favorable climate cycles occur about 10% of the time. The other 90% of the time consistent agriculture is nearly impossible. If you have any desire to explore climate science, begin here.
One of the best sources of historical climate data for the past 100,000 years is the ice covering Greenland. Alley describes the process of digging into the ice and what they have discovered so far. Dramatic climate shifts in the past were driven by much smaller changes in atmospheric energy than we have experienced over the past 60 years. Abrupt world-wide climate change in the past has taken place over three to five years, and is likely to do so again. Fascinating facts from Alley and his team.
Hansen wrote this book because of his concerns about the future world his grandchildren would inhabit. He shares basic physics explanations, as well as his thoughts about possible future climate issues. After decades of studying the physics of our atmosphere and greenhouse gases, he is certain that we are facing radical environmental changes in the immediate future. He holds degrees in Mathematics, Astronomy, and Physics, and began his career analyzing the atmosphere of Venus for NASA. Following that work he shifted to studying the atmosphere of Earth and the greenhouse effect.