Climate change may increase violence, new study finds


(CBS News) A new study found that climate change may cause people to be more violent.

The study draws a link between increased rates of domestic violence, assault and other violent crimes and a warming climate and says that aggression can be associated with higher temperatures.

Researchers re-analyzed 60 studies from recent decades that look at human behavior going back as far as 10,000 years ago. They considered violence on a large scale, such as war, and on a smaller scale such as aggression in baseball stadiums during the summer.

"Scientists found that as soon as you move off of the average of either temperature or rainfall by a certain amount you get an uptick in small-scale violence, one-on-one or little bar brawls of 4 percent, and you get large-scale violence increasing 14 percent," said Time magazine senior science editor Jeffrey Kluger on "CBS This Morning: Saturday." "And that's where you talk about governments collapsing and large-scale riots."

The study said that a global temperature increase of just 2 degrees Celsius could increase inter-group conflicts, such as civil wars, by more than 50 percent.

"By the time we get to 2050, if we don't start to bring back CO2 now, that's where we'll be, and we're facing that kind of unrest down the line," said Kluger. "One of the things to keep in mind, also, is this is worse in areas, say, with worse economies and parts of the developing world because they're on a razor's edge to begin with, so any disruption is going to be enough to tip them."

However, Kluger said that there could be other variables and it might not just be about increased heat.

"Summer, for example, has always been a time of increased crime, increased domestic violence, increased riots in cities, but how do you control for the fact that there's more hours of daylight, which means more time to be outside making mischief; kids are on the street, and you have more kids who are out of school," said Kluger. "And yet we also know personally that in a hot subway station we're more short-tempered, in a traffic jam we're more short-tempered. Studies show that police officers on shooting ranges tend to shoot their guns more precipitously when it's too hot in the shooting range."

For Jeffery Kluger's full interview, watch the video in the player above.