Is there anyone who is not familiar with the concept of global warming? Or, if one wants to use a less politically charged term, climate change? Anthropologist Brian Fagan, who has made a career out of bringing strong scholarship about the human past to the general public, takes up the challenge of explaining to a mass audience what was identified among historians as the medieval warming period lasting between about 800 and 1300 C.E.
During that period Europe enjoyed some of its greatest success, allowed by the production of much larger harvests than ever known before. Those surpluses fostered a much greater diversity of population—not everyone had to be a subsistence farmer any longer—it allowed for the development of cities, the creation of more stable kingdoms, and the funding of great public works projects. In that last category I could point to such cathedrals as that in Chartres.
Not every part of the world enjoyed such a warm period. Global warming may be the term we tend to use, but while the global climate did change not all of it was about warming. In many other parts of the world there were changing water and air currents that proved detrimental to the civilizations living there.
Drought led to crop failures, which led to malnutrition, which led to mass migrations and wars of survival. The Native American civilization in the American Southwest essentially collapsed, so did the Mayan empire. The reality of climate change effected every aspect of human actions around the globes, some for the positive as in Europe, but as often as not in a detrimental manner.
Fagan progresses civilization by civilization to catalog the nature of the changes. He never stops emphasizing the droughts that transformed, or destroyed, so many of these cultures. He also links this to current global climate change. Yes, we are seeing warming in many critical areas, but this is not uniform. What we are seeing mostly, however, is what was also recorded during the medieval warming period, considerable drought and wide fluctuations in temperature as well as more violent weather patterns than previously the norm.
With a global population so large, and the prospect of sustained global warming, Fagan believes that we are in for drastic consequences of climate change in the twenty-first century, especially among the 2.8 billion humans who live in areas where we are already seeing pressure on the water system.