The above-average temperatures that result from climate change are worrying for many reasons—and, according to a study published this week in Nature Climate Change, an increase in suicide rates is among them.
The study, which used data from the United States and Mexico across multiple decades, found that suicide rates rose when monthly average temperatures increased by one degree Celsius. The rate went up by 9.7 percent in U.S. counties, and 2.1 percent in Mexican municipalities. Using these rates, the study's authors project that climate change, on its current course, could lead to between 9,000 and 40,000 additional suicides by 2050. That rate change, they note, is "comparable to the estimated impact of economic recessions, suicide prevention programmes or gun restriction laws."
The study is not the first to point out a link between suicide rates and natural disasters—the latter of which are growing more frequent and severe due to climate change. Take post-Hurricane Katrina New Orleans as an example: In the first 10 months after the 2005 hurricane, New Orleanians committed suicide at close to three times the previous rate.
Puerto Rico has also seen higher suicide rates since Hurricane Maria. Though no comprehensive study has yet been conducted, one report shows suicides increased by 29 percent in 2017 (the year Maria hit) compared to 2016. NBC News reports that more than 5,000 people experiencing suicidal ideation called a government crisis line in Puerto Rico between September of 2017 and January of 2018.
Stress and trauma following natural disasters are factors in the increased suicide rates that follow those events. When it comes to higher temperatures, according to the new study, the heat may have neurological effects, in turn affecting overall mental health.
Climate change also has profound economic consequences—for example, food insecurity—which can in turn further affect individuals' mental health. The American Psychological Association notes that long-term climate change affects "agriculture, infrastructure and livability, which in turn affect occupations and quality of life and can force people to migrate."
Suicide is the tenth leading cause of death in the U.S., according to the Centers for Disease Control and Prevention. It's impossible to say how much climate change has affected or will affect that rate, but the authors of the new study note that the "large magnitude" of their results "adds further impetus to better understand why temperature affects suicide and to implement policies to mitigate future temperature rise."
A 2017 report from the American Psychological Association offers several recommendations for helping individuals "prepare for and recover from climate change-related mental trauma." These include cultivating coping skills, maintaining meaningful practices and healthy habits, and connecting with family and community.