Killer climate: More Americans are dying from extreme heat

The September equinox marks the end of summer in the northern hemisphere, and with it comes the end of the threat of extreme heat and its significant health impacts for this season. Yet, climate change is supercharging our environment in such ways as making our summer days and nights much hotter, more frequently, and for longer periods of time.

This means the number of people at risk for heat-related injury and death is increasing every year in line with a warming planet. This week’s announcement that large parts of the globe have passed the 2-degree Celsius threshold we have been fearing gives an urgency to concerns about the many health impacts of climate change and the need for bold and more urgent action. 

Just as rising heat is impacting health, hurricanes and other severe storms are also becoming more intense and frequent due to the changing climate. Hurricane season might not officially end until late November, but we have already seen how destructive storms like Hurricane Dorian can be to our communities and their health.

The health impacts of climate change demand our attention, and it’s important to understand how climate changes health. Extreme heat, for example, causes a variety of serious health-related conditions, including severe dehydration, heat syncope and heat stroke. Increasingly frequent heat waves can also exacerbate respiratory and cardiovascular disorders, resulting in hospitalization and even premature death. Exposure to extreme heat kills more people in the U.S. than any other weather-related threat. One estimate predicts approximately 3,400 more premature deaths each year in the U.S. due to extreme heat by 2050. 

The burden of heat-related illness and death disproportionately affects climate-sensitive populations like the very old and very young, pregnant women, the chronically ill, minorities, low-income families and people who work outdoors, such as migrant and construction workers. The very factors that cause worse health among these populations — unhealthy air, water and living conditions, heat, drought, flooding and mental health stresses — are exacerbated by the adverse effects of a worsening climate. Heat-related illness is also costly to the health care system. One heat wave can cost as much as $179 million in medical visits to emergency departments, outpatient clinics and hospitals.

What do we do about this? Heat-related and other impacts of climate change on health are significantly moderated by individual and community vulnerability and resilience. Two critical components of climate vulnerability are pre-existing health status and living conditions. In the United States, these factors are shaped by economics and the distribution of money, power, social policies and politics at the global, national, state and local levels. They differ by place, race, education level and employment, as a result of historical disinvestment in some communities, discriminatory practices and policies over time, structural racism, higher pollution burdens and lesser access to resources for health.

Some low-income communities and communities of color are disproportionately affected by the health impacts of climate change due to the lack of availability or affordability of air conditioning and/or substandard housing conditions. For example, living in an apartment that has windows nailed shut to prevent forced entry can unintentionally put residents at higher risk to extreme exposure. 

Where you live matters and determines your health. This is because your zip code determines the quality of and access to schools, jobs, housing, grocery stores, community safety and green spaces. It also determines your exposure to elevated temperatures. The built environment of a community plays a role in the severity of heat-related events because of the urban heat island effect.

Black communities tend to have fewer trees and more heat-trapping pavement, and “the rate of heat-related deaths in African Americans is 150–200% greater than that for non-Hispanic Whites.” Researchers at the University of California, Berkeley reported that people of color were as much as 52 percent more likely to live in parts of the city that were the warmest. Studies that have mapped the heat patterns over several urban areas have found that lower-income communities are as much as 10 degrees hotter than wealthier communities. 

Mitigating the effects of climate change through aggressive actions to reduce our carbon footprints must happen now. But adaptation and an urgent focus on better land use is equally essential to address this climate emergency that is affecting our most vulnerable populations.

In the short term, extreme heat adaptation requires strong partnerships between public health, planners and risk communicators to respond with proactive measures to get people out of the heat. Those measures will only succeed via a range of community tools such as cooling centers, water distribution, fan and air-conditioning unit distribution and even relocation of at-risk people. Most importantly, offering communities a voice in the decision making of interventions applied to their turf is critical to the successful treatment of the interventions.

The ultimate goal must be to ensure all of our communities are walkable, bikeable, green and cool — and, therefore, healthy.

Georges C. Benjamin, M.D., is the executive director of the American Public Health Association.