A Hotter Climate May Boost Conflict, From Shootings to Wars

In this episode of Generation Anthropocene, scientists explore the link between rising temperatures and aggression

Climate change is raising the stakes for human conflict. GBlakeley/iStock

It's a common enough axiom: when temperatures rise, tempers flare. And as climate change progresses, we can expect more extreme weather conditions around the world, from more intense storms to hotter summers—even now, heat waves are roasting the U.S. East Coast, the Pacific Northwest and the Middle East. In response, scientists are examining how rising temperatures are influencing conflict, both between individuals and on the national level. Are we headed for a future filled with more murders, skirmishes and outright war?

This week Generation Anthropocene producer Leslie Chang speaks with Stanford professor Marshall Burke, who studies how environmental change affects society. In a recent publication, Burke and his team analyzed multiple previous studies of the interaction between climate and conflict covering several disciplines. Their statistical approach revealed that the interplay goes far beyond anecdotal evidence.

"In 21 out of 21 studies, we saw a positive relationship between temperature and conflict. … The likelihood of that happening by chance is less than one in a million, right? So, this thing is real," Burke says.

One study the team looked at showed how abnormally hot summers affect police performance—when it's warmer than average, police perform worse on training exercises that involve decision-making while shooting. Other studies examined the link between changing climate and the collapse of historic civilizations, such as the Maya and the Anasazi. The team admits, though, that tracing the exact ways climate change triggers conflict is still a challenge, as many factors can influence a given scenario. Listen to the full episode to hear Burke's thoughts on possible mechanisms and what we can do about them.

Also in this episode, producer Mike Osborne examines the controversial idea of geoengineering, in which humans not only influence the climate but actually try to control it.

"Despite some recent movements, such as the EPA regulations of coal-fired power plants, there's still an expectation that globally greenhouse gas emissions will continue to go up for some decades," says guest Ken Caldeira, a climate scientist at Stanford. "This has led people to think, well, if the policy community doesn't get its act together with regard to greenhouse gas emissions in a timely enough fashion, is there something that could be done if bad things start to happen?"

Proposals for geoengineering range from slurping up excess carbon dioxide to injecting particles into the atmosphere to counteract greenhouse warming. The hitch is that no one knows for sure how effective such actions might be, or how any one nation's deliberate actions to fix the problem might affect global systems. Hear Caldeira's thoughts on the pros and cons of geoengineering in the full episode above.

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