First, climate change was blamed for coastal flooding and wildfires. The links seemed intuitive and the effects observable. But more recently, studies have probed its connection to farther afield things, like lower SAT scores and upticks in suicide rates. Now, a new report says warmer temperatures associated with the phenomenon could also be behind seasonal increases in fatal car crashes – and maybe even violent crime.
The reason for the impending social breakdown: Hotter weather makes people more sluggish, so police officers will be less willing to get out of their cars and make traffic stops as temperatures soar.
Building on this general – if oversimply stated – premise, a trio of professors from Harvard and MIT say in a paper released Monday that more frequent heat waves brought by climate change have a direct impact on law enforcement.
The study, published in the Proceedings of the National Academy of Sciences, also suggested that health inspectors – responsible for checking restaurants and roaming large processing plants and other industrial food facilities – are not immune to heat-induced indolence.
But it gets worse.
The study points out that such lethargy couldn't come at a more inconvenient time: Hot temperatures are associated with more deadly crashes, more violent crime and more health violations, meaning that police and health inspectors become less vigilant just when they're needed most.
"Do these meteorological conditions simultaneously amplify the public health risks officers are tasked with overseeing, like violent crime and vehicular crashes," the authors ask in the study. "Previous studies have found a predominately linear relationship between higher temperatures and increases in violent crime."
Those findings, they say, point to a "regulatory gap between marginal officer effort and the marginal added occurrence of violent crime at high temperatures." Less oversight, in other words, may lead to more crashes and more crime.
Scientists suspect that hot weather causes drivers to feel more fatigue, perhaps leading to more crashes. Meanwhile, bacteria thrive in warmer temperatures, which could explain the greater rate of health violations in summer. And workers at plants might also be less fastidious because they, too, are bearing the brunt of extreme heat.
"This in no way is a blame situation – in some respects it's an empathetic thing," says Harvard professor and study co-author Dustin Tingley. "These are folks who are going out and doing their jobs to protect the rest of us. And under extreme conditions, that's a really challenging job."
There is a seasonal offset: Climate change is fostering less-cold winters, meaning police and health inspectors are more active during those periods than in years past. Drivers should also think twice before trying to blame their next fender bender on global warming – much of the association remains correlation rather than causation, although the body of evidence is mounting.
Nonetheless, Tingley and his coauthors say they hope the results will spur agencies to consider more closely how to help their workers – whether cops or health inspectors or elsewhere – cope with the heat.
"It's an open question whether these agencies have the capacity to do that," Tingley says. "If people have better air conditioning, these things could dissipate. But that ignores the broader message that climate change is real and that it impacts people's performance."
That said, whether blaming climate change after a fender-bender or convincing mom and dad that global warming was behind the grade on that last test is an advisable strategy was outside the scope of the study.