Hundreds of millions of people across the globe are experiencing the impact of climate change. In the United States, hurricanes, heat waves, wildfires, droughts, and flooding — all likely intensified by a warming atmosphere — are exacting a devastating toll on communities in every region. Without drastic action, these events will only increase in scale and frequency.
Climate change also affects our health, both physical and mental. And while health care systems have an important role to play in combatting climate change, climate change deeply affects them as well. Hospitals, health centers, and other providers shoulder the burden of caring for people experiencing the health consequences of climate change. Health care facilities also often face disruptions to their operations in the form of power outages or flooding, that inhibit the delivery of high-quality care.
How does climate change affect physical and mental health?
Physical health. The toll of extreme climate events on our physical health has been well documented. Worldwide, more than 5 million deaths each year are linked to abnormally hot and cold temperatures.
Air pollution produced by wildfires is associated with respiratory and cardiovascular illness. In 2019 alone, fine particulate matter in the atmosphere resulted in at least 1.8 million deaths globally. Extremely hot weather and heat waves can lead to heat stroke and exhaustion and worsen chronic health conditions. As temperatures rise, research shows that approximately 5,600 heat-related deaths occurred each year from 1997–2006 in 297 counties where more than 60 percent of Americans live. The June 2021 heat wave in the Pacific Northwest led to 600 excess deaths in Washington and Oregon in one week alone.
Floods, the most common natural disaster, cause injuries and drownings and spread waterborne disease. In 2016, floods — excluding the landslides often caused by them — affected more than 74 million people globally.
The list goes on. More frequent and more intense hurricanes are creating widespread death, destruction, and displacement. Hurricane Katrina, which devastated the U.S. Gulf Coast in 2005, contributed to the loss of nearly 2,000 lives and displaced some 1.5 million residents.
The true toll of climate change, however, is difficult to measure. It also contributes to homelessness, hunger, and disruptions to education and the economy — all of which can have a profound negative impact on health. Moreover, these impacts aren’t just immediate: they have long-term implications for individuals and entire populations.
Mental health. Each year since 2008, an average of more than 20 million people worldwide are forced to move because of weather-related events. The impacts on mental health caused by such trauma and loss are harder to quantify than the effects on physical health. But they are no less acute.
Flooding and prolonged droughts, for example, have been associated with elevated levels of anxiety, depression, and posttraumatic stress disorder. Extreme heat can fuel mood and anxiety disorders and lead to suicide, interpersonal violence, and aggression. Alterations to the natural environment can cause grief, emotional pain, and disorientation; they can also lead to poor work performance, lower self-esteem, and harm interpersonal relationships. Geographic displacement, which could be brought about by climate change, can produce distress, anxiety, and depression — and can even weaken social cohesion.
How does climate change affect the health care system?
Climate change affects every aspect of the health care system, as Renee Salas and colleagues have described in Health Affairs. Global warming hampers access to health services as well as the quality of services provided. It can lead to major financial losses for health care delivery systems. Climate change also exacerbates existing inequities in health and health care.
Costs. As climate change and air pollution worsen the health of millions more people each year, it also pushes up health care costs. Health care systems are responsible for caring for the people facing immediate impacts, as well as people with new or exacerbated chronic conditions, like cardiovascular or respiratory illness. One study of 10 climate events from 2012 in the U.S. revealed that the health-related costs, including hospital admissions, emergency department visits, other medical costs and lost wages totaled $10 billion in 2018 dollars.
Equity. Climate change does not affect people equally; in fact, it deepens preexisting inequities by taking the greatest toll on those already at heightened risk. Exposure to climate-related stressors, individual sensitivity, and the ability to adapt all play a part in determining vulnerability to climate change. The people in gravest danger are:
- low-income people
- people of color, especially Indigenous communities
- workers in certain hazardous occupations, such as first responders and construction workers
- people living in environmentally fragile areas
- people with preexisting health conditions
- older adults
- people with disabilities
- people who are experiencing homelessness.
Research shows that extreme weather events like hurricanes are associated with long-term racial disparities and can even reverse previous equity gains. For example, Black survivors of Hurricane Katrina have more frequently reported hurricane-related problems with personal health, emotional well-being, and household finances. And the racially discriminatory practice of redlining, which stretches back more than 80 years, continues to shape environmental disparities: people of color in the U.S. are more likely to live in communities with higher rates of air pollution.
Access. Extreme climate events lead to health system disruption. Hospitals may need to be evacuated, facilities may be damaged or closed, power outages may disrupt care, and damaged roads or transit systems may prevent people from getting to health facilities. When Hurricane Sandy struck New York City in 2012, Bellevue Hospital, which serves more than 500,000 patients annually, was forced to close temporarily and move patients elsewhere.
Quality. When some hospitals are forced to close, others can become stretched beyond their capacity. Overcrowding and the boarding of patients in emergency departments are associated with decreased quality of care. In addition, disruptions to the supply chain may reduce the availability of critical medicines or medical devices. When Hurricane Maria damaged a key saline manufacturing plant in Puerto Rico, it led to dire shortages of a critical medical supply in both the territory and the rest of the U.S.
How does climate change impact the health care workforce?
Health care professionals experience the physical and mental health risks of climate change more acutely than the general population. Climate change not only disrupts their lives but also makes their jobs more challenging, raising the risk of burnout. Storms, floods, wildfires, and other extreme events often prevent them from traveling to health care facilities. As more people get sick because of climate change, there will be a greater need for a larger, climate-ready workforce.
Because climate risks to health care may be new to some parts of the U.S., it’s vital for the health care workforce to be trained in identifying and addressing these risks. In the event of health system disruption, the workforce needs to quickly adapt to delivering care under highly challenging circumstances. One study from Australia found that in a region inhabited by underserved populations, the effects of climate change were causing a third of health care workers to consider moving elsewhere.
What’s the bottom line?
When people are displaced, injured, or made ill by climate change, it’s mainly up to health systems to deal with the altered and increased health burden. Building resilience, like investing in resources to prepare for climate change and taking steps to reduce health care’s contribution to climate change, are therefore vital to ensuring the U.S. health system can meet the ever-increasing needs of all Americans.