Climate Change’s Psychological Impact

Early one morning in March 2019, armed hunters from the Dogon ethnic group surrounded the small village of Sobane-Kou in Mali, West Africa. Tensions were mounting between the Fulani and Dogon groups, who were at odds over how to use the village’s surrounding lands. The Fulani were herders, whereas the Dogon tended to farm, and a centuries-long conflict was boiling over as extreme heat, drought, and flooding made it more difficult to do either. 

By the next day, the Dogon hunters had burned swaths of the village and killed 175 Fulani residents. 

The damage doesn’t stop there. Global mental health advocates say these traumatic events can echo through a lifetime, fueling psychological distress and exacerbating underlying conditions like anxiety and depression. And some people go on to develop post-traumatic stress disorder. 

The Fulani massacre led Mental Health adjunct professor Jura Augustinavicius, and International Health associate Molly Lasater to investigate the layered consequences of a warming planet on psychological well-being. These effects will be felt most strongly in low-resource countries where climate change can worsen existing conflicts and humanitarian situations, and where mental health needs already often go unmet. 

To mitigate some of global warming’s worst psychological effects, researchers like Lasater and others are now pushing for mental health to be a focus in climate policy and interventions. 

A ‘Threat Multiplier’ 

A longtime resident of California, Lasater, PhD ’18, MPH ’14, is no stranger to the effects of climate change. She has seen friends lose their houses to wildfires and how such devastation can impact a person. 

“You always have this looming fear,” she says. Survivors of California’s 2018 Camp wildfire were diagnosed with PTSD at a rate on par with war veterans.  

But slower-onset climate change effects—like drought, rising sea levels, land cover change, and increasing temperatures—can cause stress over time that can ignite into violence like the 2019 Fulani massacre. 

What’s more, growing research shows that extreme heat can provoke aggression and increase suicide risk. In this way, climate change becomes a “threat multiplier” for mental illness, says Lasater. 

“Where poverty, unstable employment, fragile infrastructure, conflict, geographic vulnerability to extreme weather events, or food insecurity exist, there’s a greater likelihood of loss of livelihood, loss of life, or loss of a sense of control, which all have negative mental health consequences,” adds Department of Mental Health chair Pamela Collins, MD, MPH. 

Yet scientific research currently offers few solutions. Lasater and Augustinavicius are collaborating with researchers at the University of Sciences, Techniques, and Technologies of Bamako in Mali to change that. 

“Social, cultural, economic, and other environmental factors all sit in that pathway between climate change exposures and mental health outcomes,” says Augustinavicius, PhD ’17, MHS ’14, the principal investigator on the project and also an assistant professor at the School of Population and Global Health at McGill University. 

To untangle those influences, the research group is using system dynamics—an engineering approach that involves understanding complex systems through the relationships of their interconnected parts—to analyze the layered mental health impact of factors like farmer-herder conflicts, land use changes, weather patterns, and food availability in Mali. Lasater and Augustinavicius are working with local stakeholders to identify data on weather, physical and mental health, social and health services, and resource access to advance the work.  

Their aim is to begin to tease out how climate-related factors contribute to feedback loops of displacement, conflicts, and migration in the region that threaten physical and mental health. With the data, the researchers hope to better understand how these environmental changes ripple out to mental health and, ultimately, to incorporate interventions. 

New Policies and Interventions 

“My long-term goal is to think about integrated programs,” Augustinavicius says. These might directly address psychological well-being—such as a campaign to raise awareness of mental health impacts of climate change—or support well-being through more indirect routes, such as ensuring that people with psychosocial disabilities can access to early warning systems.  

Still, mental health and climate policies are “very nascent,” says Alessandro Massazza, an adviser at United for Global Mental Health and an honorary research fellow at the Centre for Global Mental Health at the London School of Hygiene & Tropical Medicine. For example, the action plans for reducing emissions and adapting to climate impacts submitted every five years by parties to the Paris Agreement rarely mention mental health.  

Massazza urges governments and policymakers to consider mental health when drafting climate policies. He points to South Australia’s heat warning system as one success story. The region’s action plan mandates notifying those with existing mental conditions of extreme heatwaves, via a phone call, and conducting a welfare check if there is no response. It also provides free mental health support to emergency workers involved in climate-related disasters.  

On a local scale, Lasater advocates for strengthening physical and mental health services, promoting community support, and destigmatizing mental health—services that are best accompanied by other efforts, like vaccination, nutritional support, and climate change mitigation and adaptation programs. 

Why Mental Health Matters 

With climate change threatening people’s physical safety, lives, and livelihood, focusing on mental health may seem like a Band-Aid solution.  

But “the distinction between physical and mental health is, to a degree, quite arbitrary,” says Massazza. An oft-cited example is that depression can make people with HIV less likely to take their HIV medication, or make it harder for them to access HIV services. Connections like these make climate change’s status as a “threat multiplier” even more acute, as the mental health impacts could also influence physical health. 

And all of this comes with a hefty price tag: A 2023 Annals of Global Health study found that mental disorders due to climate, pollution, and environment-related causes could cost the global economy $47 billion annually by 2030. 

But more importantly, says Augustinavicius, preserving mental health is key to staying resilient in the face of a changing planet. “Mental health and well-being are really at the core of our humanity,” she says. “And that means they're also at the core of our ability to address this problem.”