The Grapevine

Suicides In US, Mexico Could Increase Due To Global Warming

After analyzing data regarding temperatures and suicide in the regions, researchers suggested climate change could lead to an increase in suicide rates across the United States and Mexico.

The findings of the new study were published in the journal Nature Climate Change on July 23.

Given the temperatures we are expected to hit by the year 2050, researchers have estimated suicide rates could increase by 1.4 percent in the U.S. and by 2.3 percent in Mexico i.e. an additional 21,000 cases.

"When talking about climate change, it’s often easy to think in abstractions," said Marshall Burke, assistant professor of Earth system science in the School of Earth, Energy & Environmental Sciences at Stanford University. "But the thousands of additional suicides that are likely to occur as a result of unmitigated climate change are not just a number, they represent tragic losses for families across the country."

Over the years, from as far back as the 1800s, trends have revealed the number of suicides is higher during warmer seasons such as summer and spring. Texas, one of the hottest states in the country, was found to have a high suicide rate. Furthermore, the numbers have been on the rise, according to recent data.

But establishing a prominent factor has been challenging as unemployment rates, daylight exposure and many other factors can be hard to separate. Some experts suggest sunlight can increase serotonin levels, which might increase aggressive behavior in people diagnosed with depression. Similarly, another theory put forward involves the impact of seasonal allergies and inflammation.

"Hotter temperatures are clearly not the only, nor the most important, risk factor for suicide," Burke stated. "But our findings suggest that warming can have a surprisingly large impact on suicide risk, and this matters for both our understanding of mental health as well as for what we should expect as temperatures continue to warm."

For the new study, the research team analyzed decades' worth of data regarding temperature and suicides across thousands of counties and municipalities in the U.S. and Mexico. They also examined the kind of language used on social media. The incidence of certain words (such as "lonely," "trapped" or "suicidal") was measured in more than half a billion tweets.

According to the press release, the research team found "strong evidence that hotter weather increases both suicide rates and the use of depressive language on social media."

When examining the literature on conflict and violence, it was found people fought more during hotter temperatures, said Solomon Hsiang, study co-author and associate professor at the University of California, Berkeley. 

"Now we see that in addition to hurting others, some individuals hurt themselves. It appears that heat profoundly affects the human mind and how we decide to inflict harm," he added.

If you have thoughts of suicide, confidential help is available for free at the National Suicide Prevention Lifeline. Call 1-800-273-8255. The line is available 24 hours, every day.