The Winds of Change by Eugene Linden

At the end of the last century, Jared Diamond provoked a great deal of debate with his Pulitzer Prize-winning Guns, Germs, and Steel, in which he argued that the success of a civilization (and particularly European civilization) is not based on cultural or racial superiority, but environmental factors that are largely out of human control. Even if Diamond is correct (I have no basis for taking sides, as I have yet to read what I'm sure will be a fascinating text), it is no surprise that many were taken aback by a theory that removes so much credit for worldly success from human agency. It would rather undermine the power and purpose of most work previously done by political scientists, economists, and anthropologists.

In The Winds of Change, Eugene Linden posits another element he thinks has received insufficient attention as an influence of human civilization: rapid climate change. He argues that "[e]merging evidence suggests that climate may well be a serial killer of colonies and even civilizations," but notes that this notion has met considerable resistance from the academic establishment:

Many historians, archaeologists, and anthropologists dispute the role of climate as a factor in history. John Steinberg, the UCLA archaeologist, put this reaction succinctly: "Most archaeologists are anthropologists at heart, and most anthropologists hate the assertion that human are not in control of their destiny."

For every example of a historical collapse coincident with a dramatic shift in climate, there is an archaeologist or historian who will argue that technological, cultural, political, or economic factors were more important. In the course of this book, I will try to fairly represent these counterarguments. Climate history if still a very young field.

Indeed, Linden makes clear that most of the meaningful work has been done in just the last couple decades, as the technology has advanced to allow analysis of the climate record with sufficient specificity to connect it to human history. These advances have led Linden and others to two conclusions. The first is that climate change can occur much more quickly than previously believed:

The 1990s saw an extraordinarily rapid advance in the understanding of past climates, and this advance in understanding the past precipitated a dramatic shift in the paradigm of how climate changes. As Peter deMenocal puts it, "When I began my Ph.D. in 1986, the conventional wisdom was that it took one thousand years to end an ice age. By the time I finished in 1991, that figure had been reduced by an order of magnitude to one hundred years. Just two years later, Richard Alley showed that climate could change from warm to glacial conditions in two to five years."

Linden's second conclusion is that rapid climate change has been a significant factor in the decline of several colonies and civilizations in human history. In the book's initial chapters, Linden walks through a series of examples where he thinks this has occurred. The first, and most speculative, was a dramatic cooling 8,200 years ago, just "as tribes in the Levant began to build the first protocities, develop agriculture, and organize themselves into complex societies." Linden, backed by the arguments of Harvard archaeologist Ofer Bar-Yosef, suggests this "cold event stopped this process in its tracks, interrupting the progress of the first stirrings of civilization," not to be restarted in full until the rise of the first Mesopotamian civilizations, three thousand years later.

There is more evidence to support Linden's argument that the downfall of the Akkadian civilization can be traced to rapid climate change. In addition to the Greenland ice core which has served as one of the foundational pieces of evidence in the field, "dozens of other records have surfaced or been developed that confirm that 2200 B.C. was a period of drought in the Middle East and dramatic climate change around the world." This date is key, because it connects to the abandonment of one of the Akkadian's great cities, Tell Leilan:

One day, when workers were constructing a wall in part of the acropolis, work simply stopped. Half-dressed blocks were abandoned; other materials were left scattered about. Workmen had dropped what they were working on and left in a hurry.

What were they fleeing? Invaders? A plague? Most probably they were fleeing starvation. Those left behind did not fare very well. Excavations reveal a very large spike in infant burials in the years after 2200 B.C. Building that wall was possibly the last act of construction in Tell Leilan for the next three hundred years.

Other chapters are devoted to the fall of the Mayans and the Norse abandonment of their colonies on Greenland. After these historical examples, Linden offers a neat venture into the nature of the scientific process, with one chapter devoted to ice and one to mud (with interesting tidbits about scientist's competitive loyalty to their own source material). Unfortunately, Linden tends to repeat himself quite a bit. He offers bits of evidence as new information in late chapters, apparently forgetting he had already discussed the same data. It's a bit annoying considering the book has less than 300 pages.

One other minor irritation has to do with Linden's calendar scheme. He can't seem to decide whether to use the Christian calendar (500 B.C.) or simply date things from the time the book was written (2500 B.P.). Even worse, he sometimes changes back and forth. On a single page describing the fall of the Akkadian Empire, he dates the abandonment of Tell Leilan to "4200 B.P.," "2200 B.C.," and "4,200 years ago." He even confuses himself, at one point listing "4200 B.C." as the relevant date. It's not that I particularly care which dating system he uses, though the "before present" system seems silly as it requires the reader to know when the book was written. I just want a little consistency.

After an extended discussion of El Niño (including a startlingly connection to 19th century famines in India), Linden turns to present-day climate change, what he calls "The Elephant in the Room." He begins with a riff on the ebb and flow of public opinion over the past two decades, in contrast to the growing unanimity in scientific circles. He has particular ire for the media's portrayal of climate issues:

The standard climate-change template for the national media usually begins with a peg--a collapsing ice shelf, a heat wave, retreating glaciers, devastating hurricanes--and then offers a scientist who ties the event to a warming globe. The story usually includes a recapitulation of the basic science (which eats up a good deal of the story), a bit on the many unknowns of future climate changes, and then gives the naysayers a chance to dispute the notion that climate change is a threat... With so much space given over to the rudimentary science and venting by naysayers, the public was left with the impression that there was active debate about the threat long after the scientific community reached consensus.

Sounds a lot like the way the media has been treating the current election, right? Start with an event, say, John McCain lying about something. Give a Democrat a chance to discuss it, give a Republican a chance to obfuscate, deplore the ugly state of modern campaigning, then fail completely to point out that John McCain was, in fact, lying. The profession is, in John Marshall's terms, fundamentally corrupt.

Still, as valid as Linden's 40 page discussion of the global warming crisis may be, it is an awkward fit at the end of this book. While he does connect the crisis to current research being done concerning the possible shutdown of thermohaline circulation, it feels like an extended editorial on the author's frustration with the public and politicians. Well-founded frustration, sure, but the first 200 pages of the book were an introduction to scientific theories regarding rapid climate change and historical examples that had no roots in human activity. So while human activity is surely dramatically influencing the current climate at present, Linden's book actually seems to demonstrate how catastrophically our climate can change without any help from us.