I stood on a rooftop in Vancouver’s Downtown Eastside last July, watching as outreach workers distributed water bottles to people seeking refuge in whatever shade they could find. The temperature had climbed to 34°C, and the unrelenting heat seemed to distort more than just the horizon. Agitation rippled through the community. A woman named Elaine, who has lived on these streets for nearly a decade, told me something I couldn’t shake.
“It’s not just about being hot,” she said, fanning herself with a folded newspaper. “The heat makes everything worse in my head. I can’t think straight, can’t sleep. My meds don’t even work the same.”
What Elaine was describing goes beyond physical discomfort. As our planet warms, researchers are uncovering alarming connections between rising temperatures and deteriorating mental health—a crisis that healthcare systems worldwide are woefully unprepared to address.
The research is compelling. A 2018 study published in Nature Climate Change analyzed data from over 2 million Americans and found that suicide rates rise by approximately 0.7% for each 1°C increase in monthly average temperature. When I spoke with Dr. Hasina Samji, an epidemiologist at Simon Fraser University who studies climate impacts on health, she wasn’t surprised.
“Heat stress affects brain function directly,” Dr. Samji explained. “It disrupts sleep, increases irritability, and can exacerbate existing mental health conditions. For many vulnerable populations, extreme heat events are becoming a significant mental health trigger.”
The effects go beyond those with diagnosed conditions. Emergency departments across British Columbia reported a 13% increase in mental health-related visits during last summer’s heat dome event compared to seasonal averages, according to data from the BC Centre for Disease Control.
For Indigenous communities in northern Canada, these impacts compound historical traumas. Last month, I traveled to a Dene community in the Northwest Territories, where unprecedented temperatures have disrupted traditional hunting practices and cultural activities.
“When the land changes, we change,” Elder Robert Beaulieu told me as we sat by Great Slave Lake. “Our young people already struggle with identity and purpose. Now the heat brings uncertainty about our future on this land. It weighs on the spirit.”
This mental health burden falls heaviest on those already marginalized. People experiencing homelessness, like Elaine, have nowhere to escape the heat. Those with serious mental illness often take medications that impair the body’s ability to regulate temperature. And many low-income neighborhoods lack green spaces that could provide crucial cooling effects.
Dr. Nick Watts, Chief Sustainability Officer at the UK’s National Health Service, recently warned that health systems are “flying blind” into a future where heat-related mental health impacts could overwhelm already stretched resources.
“We’re seeing a perfect storm,” Dr. Watts told me during a virtual interview. “As temperatures rise, we’ll need more mental health supports precisely when our healthcare workers are themselves struggling with climate impacts. Few countries have meaningfully prepared for this.”
The World Health Organization estimates that between 2030 and 2050, climate change will cause approximately 250,000 additional deaths per year. What’s often left unstated is how many millions more will suffer mental health consequences that may not be fatal but will significantly reduce quality of life and productivity.
Solutions require both immediate interventions and systemic change. Cities like Melbourne have begun identifying “cooling routes” and installing water fountains in high-risk neighborhoods. Phoenix has established cooling centers specifically designed to support those with mental health needs during extreme heat events.
In Canada, the Mental Health Commission has partnered with climate scientists to develop resources for healthcare providers, but implementation remains inconsistent. When I asked about heat preparedness at several Vancouver clinics, most staff admitted they had no specific protocols for supporting clients during extreme temperatures.
“We’re still treating this as an occasional emergency rather than a new normal,” said Dr. Maya Gislason, a health geographer at Simon Fraser University who studies climate justice. “Mental health services need complete redesign to function in our changing climate.”
For individuals like Elaine, these academic discussions feel disconnected from immediate needs. When I checked in with her during a follow-up visit in August, she had developed her own coping strategies—wetting a bandana to wear around her neck, finding basement locations where she could cool down, and adjusting her medication schedule with her doctor’s guidance.
“Nobody’s coming to save us,” she told me with surprising clarity. “We have to figure it out ourselves.”
As temperatures continue rising globally, her words reflect a harsh reality for millions. The intersection of climate change and mental health represents one of the most significant public health challenges of our time—one that demands immediate attention, substantial resources, and creative solutions that center the experiences of those most affected.
Walking back through the Downtown Eastside that evening, I noticed small acts of community care unfolding despite institutional gaps—neighbors sharing cold drinks, checking on elderly residents, creating improvised cooling stations with garden hoses. These grassroots responses offer lessons for formal systems that have been slow to adapt.
The heat-mental health connection forces us to reckon with climate change not as a future threat but as a current crisis already reshaping our collective wellbeing. The question isn’t whether extreme heat will impact global mental health—it already is. The question is whether we’ll respond with the urgency and compassion this moment demands.
