Heat Increases Crime

Why Heat Increases Aggression

This topic has implications for those living in cities as well as for people in rural areas. I wanted to talk a bit about the relationship between heat and crime. While it has been establishes that cities are safer than rural areas, both types of areas experience spikes in crime during heat waves and during warmer months in general. 

One of the first studies about heat and aggression was this one shown in the graph. As you can see, hotter weather tends to lead to more riots. Similar studies have been conducted in many cities. Houston, TX for example studied the increase in murder rates that tend to occur during the summer months. So interesting, but what exactly is it that makes people more aggressive in the heat?

Heat Increases Testosterone Production: The hotter it is outside, the more the body naturally produces testosterone. Particularly in men, testosterone production is linked to aggression. The more testosterone a person has, the more statistically likely they are to act in an aggressive way. 

Increased Time Outside: When temperatures rise, more people come out from their homes. Interactions between people increase and alone this enough can increase the likelihood that someone will be involved in a crime. When there are more people in an area, the percentage of people committing crimes may stay the same, but total crimes may increase. Heat almost artificially boosts population by bringing people together.

More Irritable: This one is perhaps the most subjective, but lots of people struggle to sleep when it is too hot. Many people do not have air conditioners and so in the summer have to sleep in extreme temperatures. Heat can make it harder to fall asleep, leading to less sleep per night. When people get less sleep they tend to be more short tempered and irritable. This can lead people to act in more aggressive ways towards others.