For the Inuit of Labrador in Canada, climate disaster has already arrived. These indigenous people form an intense bond with their land, hunting for food and fur. “People like to go out on the land to feel good,” says Noah Nochasak in the documentary Lament for the Land. “If they can’t go out on the land, travel a long ways to feel good, they don’t feel like people.”

The Inuit’s lands, though, are warming twice as fast as the global average, imperiling the ice they rely on to travel. In the fall, hunters tend to get stuck in the community, because ice hasn’t fully formed up—and again, in the spring, when things are melting. Climate change is making these ice transition periods even longer.

“During those times historically, there has been some increases in suicide or suicide attempts or ideation in the communities,” says Ashlee Cunsolo, a health geographer who has studied the region. “There is a lot of concern among the mental health practitioners. What does that mean if this time is lengthened from two weeks to eight weeks?”

It’s known as ecological grief—the mourning of ecosystems and species and ways of life that are disappearing as the planet warms. But it isn’t just hitting the Inuit. As our planet plays host to rising seas, more intense storms, and higher temperatures, those conditions will support a growing international mental health crisis.

“Things like depression, anxiety, post traumatic stress disorder, substance abuse, domestic abuse, all these things tend to go up in the aftermath of a natural disasters,” says psychologist Susan Clayton of the College of Wooster, co-author of an extensive report on climate change and mental health. “As we have more natural disasters, one would expect to also have increases in those kinds of mental health consequences.”

Take Hurricane Katrina. In its aftermath, a sample of survivors found one in six met the criteria for PTSD. Rates of suicide and suicidal thoughts doubled. And especially in refugee situations, those mental health challenges can be intimately tied to physical health, compounding the harm. “When people are moving to places they bring diseases with them that the home population might not be immune to, and on the flip side these people are moving into places where they might not have immunity to the diseases in the new place,” says Jonathan Patz, director of the Global Health Institute at the University of Wisconsin.

Even those whose homes aren’t directly threatened by sea level rise or fiercer hurricanes aren’t immune. By the end of the century, the average American will have to endure four to eight times the number of 95+ degree days. Arizonans will get it particularly bad: Their number of 95+ degree days a year will leap from an average of 116 to over 200. And several studies have made a link between higher temperatures and higher rates of suicide.

One particularly data-intensive survey recently published in Nature Climate Change compiled temperatures and suicide statistics on the county level for the US, and municipality level for Mexico. They compared these granular regions not with each other, but with themselves—so the average monthly temperature in Palo Alto in July 2009 versus July 2010. This controlled for differences between locations in factors like poverty rates or gun ownership rates, both of which have been tied to suicide rates.

The uptick in suicide rates the researchers found may be small—a rise of 2 percent in Mexico and .7 percent in the US for every additional degree Celsius in average monthly temperature—and the relationship is far from simple. Rates of suicide fluctuate around the world, and where those suicide rates are highest, the temperature isn’t necessarily the highest. But extrapolated forward, the impact on public health could be devastating. “The fact that our results are so consistent across different socioeconomic strata, across different populations, suggests a common biological response,” says Stanford economist Marshall Burke, lead author of the study.