The Long Summer: How Climate Changed Civilization
The Long Summer: How Climate Changed Civilization – Review
Many of the chronological questions that previously existed, such as why the Mayan civilization collapsed, have since been fully explained by long term climate change, particularly drought. I am unsure what Fagan’s special purpose was in writing this book, which isn’t very systematic, but certainly much of it is interesting. Fagan’s major problem is what to do about currently providing the facts and kind of longer term climate change; consequently he can be potentially confusing, so I recommend this book as a possible follow on to Fred Pearce’s great book, “With Speed and Violence: Why Scientists Fear Tipping Points in Climate Change”. Fagan is also concerned with brief term climate change (lack of a year or two or even perhaps the Biblical 7 years) and how civilizations survived to survive them. When geographic areas were way below potential population densities, survival usually involved mobility, and/or receiving benefit of less popular foods. When population densities were high, food storage, and the ability to take benefit of food in other areas through empires, kin relationships or trade offered answers. The strongest section of the book is Fagan’s imagining of what life was like in Cro-Magnon Europe, before and during a warming period, and in the earliest Mesopotamian and Egyptian settlements. Among the many pieces of information in the book is that the quantity of animal protein that humans can safely consume without long term health consequences, even when life expectancy is relatively short, is fifty per cents; the percent requires to be even lower for pregnant women. Another nugget that struck me is that nomads in arid areas can herd cattle rather than sheep or goats because cattle can survive longer without water. I don’t completely trust Fagan as to accuracy. On p.42 he contradicts himself in successive paragraphs as to the Siberian climate between 20,000 and 18,000. He discusses how farming spread into Europe without any mention of what genetic analysis has to say (issue is whether people went or practices were copied). And as I reportedly said, his discussion of climate is sometimes muddled.