Two new studies warn that a hotter world will be a more violent one

As the planet warms, experts have increasingly sounded the alarm over the potential for increased climate-driven geopolitical conflict. Two new studies underscore how rising temperatures are likely to increase aggression and violent behavior at the individual level as well. They arrive at a similar conclusion using two very different data sets: crime in Los Angeles and terrorist attacks around the world.

The first study, released last month by the National Bureau of Economic Research, examines the relationship between daily high temperatures and incidents of violent crime in Los Angeles between 2010 and 2017. Criminologists have known for decades that murder and other violent crimes tend to be more frequent in the hot summer months. Here, for example, is a comparison between monthly homicides and average high temperatures in the city of Chicago.

The charts share the same general outline, peaking in July and then receding toward the winter months. But this simple correlation is complicated by a number of factors. Schools are out in summer, meaning many teens and young adults, who account for a disproportionate share of violent crime arrests, have more free time on their hands.

View the complete July 16 article by Christopher Ingraham on The Washington Post website here.