Violence Linked to Higher Temperatures


Cops anywhere can tell you that when the temperature rises, so does the crime rate. So what’s going to happen when the whole planet gets hotter? The answer gleaned by a recent analysis of 60 detailed studies covering a time span from 10,000 BC to the present is, well, pretty grim. The authors of “Quantifying the Influence of Climate on Human Conflict,” published in Science, conclude there is a strong causal link, not just a coincidental one, between warmer temperatures and violence—and the problem is not only one of crime, but also of war. Even a relatively slight increase from the current norm (say, a jump of less than one degree in Africa) can lead to a 4 percent increase in violence among individuals, and a frightening 14 percent increase in violence among groups. By 2050, those numbers could double or quadruple. The evidence comes from a lot of different angles—archeology, criminology, economics, geography, history, political science, and psychology—and the authors concede that climate is not the only, or even the primary, cause of conflict. But it is one that “appears to extend across the world, throughout history, and at all scales of social organization.”