Perhaps you’ve seen the news: “Hotter Weather Actually Makes Us Want to Kill Each Other.”
That’s the snappy title that The Atlantic used to describe a new academic paper that looks at the relationship between climate change and human conflict.
A joint effort between public policy and economics wonks at Berkeley and Princeton, the meta-study (or study of other studies), recently published in Science, is a multidisciplinary sift through some 60 pieces of academic literature—from history and archeology, economics and political science, criminology and psychology—which comes to the unambiguous (if unsurprising) conclusion that bad weather tends to bring out the worst in all of us. Needless to say, it also brought contentious commentary.
Whether the violence is interpersonal (as measured by an uptick in violent crime, road rage incidents, or beanballs thrown during a baseball game) or intergroup (civil wars in West Africa, ethnic violence in India), conflict, the study claims, tends to flare up with dramatic fluctuations in weather patterns. This was generally found to be true of cold snaps, dry spells, and periods of unexpected rain, but nowhere was the connection between nasty weather and nasty behavior so consistent as with unusual spikes in temperatures. Out of the 27 studies that looked at modern incidents of conflict, all 27 found a positive correlation between hot weather and hot tempers.
Since the publication of the Atlantic article—and innumerable follow-up pieces from such outlets as CNN, NPR, and The Guardian—the report has, as with all things that brush up against the subject of global warming, attracted a certain amount of criticism. The study confuses weather and climate. The data is cherry picked. What does baseball have to do with witch hunts in Tanzania, anyway?
Marshall Burke, a Ph.D. candidate at Berkeley and one of the co-authors of the study along with Solomon Hsiang and Edward Miguel, responds to these points in a blog post published last Friday in which he addresses eleven of the “FHC” (that is, “Frequently Heard Criticisms”) of the study. You can read his lengthy defense (and some additional back-and-forth in comment section) for yourself, but when I spoke to Burke last Friday afternoon, I simply asked him if he was surprised by the controversy.
“Journalists are doing the normal thing that journalists do by showing that there’s a debate within the literature,” Burke said. “It’s not that we don’t disagree, but it suggests that there’s more debate than there really is. I’m buddies with a lot of these people.”
The “most reasonable” criticism, he says, “is the question of how you link our results to future climate change.”
Certainly the paper’s moment in the limelight has almost nothing to do with what it tells us about the past and everything to do with what it might portend for the future. If climate change—particularly, warmer weather—corresponds to a spike in murdering, pillaging, warmaking, and beanballing, does this graph-strewn academic paper read like a warning of dystopic things to come? Here, Burke and his co-authors are careful to keep their prophecizing in check.
“If future societies can figure out how to adapt to climate changes in ways that we haven’t been able to, then sure, our results don’t mean much,” says Burke. “But I will say that that is a dangerous assumption to make. Based on our results, we can’t just assume that people will get better at adapting.”