The Midwest has been drenched by rain and beset by floods. California is bracing for wildfires after several years of record-breaking burns. Hurricane season is just getting into gear in the Atlantic Ocean, which has been hit by more storms than usual over the past three years, and those storms have been above-average in intensity. Heat waves have been increasing across the country for decades. Just last weekend, New Yorkers were being warned to use less air conditioning to prevent blackouts — and to charge their phones for when the blackouts would inevitably happen.
After three summers in a row of major natural disaster headlines, there’s a good chance that if you aren’t currently experiencing a disaster, you’re bracing for one, wondering whether (or how) summer will strike. Public health organizations and media talk a lot about the “new normal” — the idea that, as climate changes, disasters that were once rare events are increasingly common. That could also translate to a new normal for mental health. What does it mean for our emotions when summer is spent waiting for something bad to happen?
There’s a short answer and a long answer to this question. The short version is, basically, we don’t know yet — but scientists are really interested in finding out. “You’ve probably seen all kinds of anecdotal reports of anxiety associated with climate change,” said Susan Clayton, professor of psychology at The College of Wooster. “But there’s not much concrete data we can refer to.”
That’s partly because the single, seemingly simple question is actually a tangle of ideas, and it’s not clear whether existing surveys tease them apart effectively. For instance, a December 2018 survey from the Yale and George Mason University climate change communication programs found that 69 percent of Americans are at least somewhat worried about global warming. But we don’t know much about what that means on a day-to-day basis, Clayton told me, or whether levels of concern change throughout the year. In other words, we don’t know how strongly nebulous fears about climate change map onto more specific fears about, say, this hurricane season. And we don’t know whether there’s a difference between an anxiety about simply living in a place where you’ve seen neighbors’ houses burn down in wildfires and an anxiety that the risk of losing your house is exacerbated by climate change.
But the question is still important, experts said. Based on what we do know about the mental health impacts of natural disasters and climate change, separately, it’s reasonable to suspect that there’s a mental health cost to watching climate-linked weather disasters play out year after year.
There’s definitely harm associated with experiencing a natural disaster. And much of the research on mental health and climate change have focused on linking disasters that have ties to changing climate with the effect those disasters have on survivors. We’ve previously reported on the health surveys that were underway in New Orleans before Hurricane Katrina hit; those surveys ended up helping scientists understand the far-reaching effects of stress and depression after a natural disaster. Rates of headaches and migraines, for example, jumped by 41 percent among survivors following that storm.
But scientists are also starting to accumulate evidence of climate change affecting emotions in ways they hadn’t anticipated. For instance, we used to believe that the people particularly worried or depressed about climate change were, primarily, people who were generally worried and depressed. But that doesn’t seem to be holding true, Clayton told me. It’s not just the people who are showing signs of underlying mental health issues — at least, not anymore.
Conversely, it’s pretty logical to assume that surviving a second climate-linked natural disaster might make someone extra anxious and exacerbate mental health issues caused by the first brush with danger. But that’s not necessarily true, said Carl Weems, professor of human development and family studies at Iowa State University. He has followed children who survived Hurricane Katrina and went on to experience Hurricane Gustav in 2008. He expected to see anxiety and PTSD symptoms go through the roof after the second storm hit. “But what we saw was an average decrease,” he said. “Gustav was a much more mild event. The evacuation was effective, the levees held.”
What’s more, Weems said, his subjects remember Katrina as less terrifying now than they did before going through the second hurricane. Memory, he told me, is pliable, and theirs seems to have changed in response to facing a fear and experiencing a better outcome.
And climate change can end up affecting mental health even if the weather you’re experiencing doesn’t register as a natural disaster. Last year, researchers at MIT published a paper connecting weather data with data from a mental health survey that had been conducted over the course of a decade. They found that as the places in which the surveys took place got hotter and wetter, the people surveyed were more likely to report mental health problems, such as stress or depression. Since 1970, average temperatures in every state have risen by at least 1.8 degrees Fahrenheit. A 1.8-degree increase in average maximum temperatures was associated with a 2 percentage point increase in reported rates of negative mental health.
This research doesn’t add up to a single clear narrative about the effects of chronic, long-term climate changes and repeat disasters. But one thing it does tell us is that you can’t necessarily rely on either of those things to change the way people relate to climate change from a policy perspective. If mental health can be affected by heat that isn’t clearly pegged as a disaster, and if experiencing disasters multiple times can end up making them seem like less of a big deal in retrospect, there probably isn’t a clear line connecting disaster to fear to action. Whether we feel bad and what we do about it are two different things.
Maggie Koerth-Baker is a senior science writer for FiveThirtyEight. @maggiekb1