A warming climate may carry a sneaky effect on mental health. A Stanford University-led research team warns in a study published today that hotter temperatures are raising the risk of suicide.
Going back to the early 19th century, scientists, sociologists and poets all noticed more people die by suicide in spring. That’s caused other teams to investigate sunlight’s influence on mental health and the connection between allergies and suicide.
Marshall Burke, an associate professor of earth systems sciences at Stanford, worked with colleagues at UC Berkeley and an international team to amass decades of death records for the U.S. and Mexico, and localized temperature records. They found that when temperatures rose about 2 degrees Fahrenheit in a given location and given month, deaths by suicide rose by about 1 percent.
“Even a one percent effect - if multiplied across many people in the United States - implies a very large additional health burden from increasing temperature,” says Burke.
Globally, nearly 800,000 people die by suicide each year, according to the World Health Organization. Suicides in the United States and Mexico represent abut 7% of the total. In the United States, suicide is a top-ten leading cause of death, and in the most recent 17 years on record, the nation’s overall suicide rate has increased 28%, according to the National Institute of Mental Health.