lise-van-susterenAs part of the Year of Climate Change and Health, psychiatrist and environmental activist Dr. Lise Van Susteren discussed the challenges climate change poses to mental health at this month’s “Building Mental Wellness and Psychosocial Resilience for Climate Change” workshop. Van Susteren is co-founder of the Climate Psychiatry Alliance and is on the advisory board of the Center for Health and the Global Environment at T. H. Chan School of Public Health at Harvard University. We’ve adapted her remarks for the blog post below.

In the last two decades, severe weather events like storms, floods, wildfires and extreme heat have wounded, displaced or required emergency assistance for 4 billion people. Half a million have died. When the place you call home burns down, blows away, or floods; when you lose your possessions, maybe your pets, your livelihood; when you see injuries illness and death, the mix of fear, anger, sorrow and trauma can easily send you to a breaking point.

Mental health professionals are seeing a full range of psychiatric disorders emerge in these situations. Major depression, anxiety, PTSD, suicide, a rise in drug and alcohol abuse and domestic violence emerge as people attempt to cope. Following Hurricane Katrina, 49 percent of survivors developed an anxiety or mood disorder and one in six developed PTSD. Suicide and suicidal ideation more than doubled.

But climate change is about more than severe weather events. Rising temperatures, elevated sea levels and changing precipitation patterns can cause chronic stress that leads to conflict. According to findings in the journal Science, for each standard deviation of increased temperature and rainfall, we can expect a 4 percent increase in conflict between individuals and a 14 percent increase in conflict among groups. As resources become scarcer and the competition for them becomes fiercer, fragile nations can fail and refugee crises increase.

Every 1 degree centigrade rise in temperature above 86 degrees Fahrenheit results in an average 10 percent decline in crop yields for wheat, rice and corn. Considering this fact alone, it’s easy to understand the stress that comes from the resulting economic strain and food insecurity. Drought from persistent high temperature is driving up suicides among farmers in India, rural Australia and South Africa. It is leading to rationing and water wars in the U.S. — compounded by crumbling infrastructure highlighted by the Flint, Michigan, water contamination crisis.

This is a global concern, as 15 of the 16 hottest years on record have occurred since 2001, and 2017 may be on track to be the hottest year ever. Higher temperatures and less rainfall dry out land and lead to an increase in the number and severity of wildfires. The smoke from wildfires is extremely toxic, impairing both our respiratory and cardiac functions at a distance of hundreds of miles. High temperatures from climate change favor the formation of ground-level ozone, which has a wide range of health impacts — a direct corrosive effect on lung tissue, cardiac functioning, cancers, even lifelong diminished lung volume in children. Higher C02 levels are responsible for longer and more intense allergy seasons.

Polluted air causes inflammation of brain tissue. Multiple lines of evidence support the role of neuro-inflammation in classic psychiatric illness, such as major depressive disorders, bipolar disorder, schizophrenia, obsessive-compulsive disorder and in dementia, Parkinson’s Disease and ALS. Children and the elderly are particularly vulnerable. The American Psychological Association reported that children exposed to small particles of chemicals in the air were more likely to have symptoms of anxiety or depression. Emergency room visits for anxiety and suicide threats are significantly higher on days with poor air quality.

Also, we should not underestimate the toll that loss of wildlife — an estimated 40 percent over the last 50 years — has on human health and well-being. Climate change is harming entire ecosystems. While adaptation has always been a cornerstone of evolution, conditions are now changing so fast that nature, in many instances, is unable to keep up. High levels of C02 dissolve into our oceans, causing increased acidification. The increasingly acidic (and warm) waters harm coral reefs and other marine life. Dubbed the oceans’ “nurseries,” three out of five marine animals depend on the coral reefs as part of their food web. More than a billion people rely on food from the ocean as their primary source of protein.

And tens of millions of Americans alone live along coastlines. By the estimates of Columbia adjunct professor James Hansen, global sea levels could rise by 10 to 13 feet in another 50 to 150 years. Climate change evokes a profound sense of anxiety from feelings of powerlessness. As climate trauma and chronic stress cause and exacerbates mental health and other conditions, we must steel ourselves with resolve and resilience. We must take the empowering action of conducting a “personal inventory” of our own carbon footprint to see where we can contribute to the solution.