What you need to know
- Climate change is causing weather conditions that are increasingly harmful to our lungs.
- A recent study found that dangerous events caused by high heat and humidity have become more common.
- Extreme heat, poor air quality, and intensified allergy seasons brought on by climate change can create respiratory issues and worsen existing lung conditions.
The weather can have unexpected impacts on your lungs’ short and long-term health. Climate change has increased the frequency of “wet bulb” events, which occur in hot weather when high humidity prevents sweat from evaporating and cooling the body.
“These are, in my opinion, one of the scariest byproducts of climate change,” said Maiya May, a science communicator and host of PBS’s Weathered: Earth’s Extremes, in a June video.
She emphasized that though wet bulb events have been “relatively rare historically,” they are becoming more common due to climate change.
Recent research suggests that the level of humid heat that humans can tolerate is much lower than previously believed. A March study found that as humidity rose, temperatures as low as 79 degrees Fahrenheit put humans at risk of damaging effects from heat.
At the current rate of global warming, much of the world’s population will face wet bulb events within a decade. Here’s what that means for the health of your lungs.
Extreme heat makes breathing harder
You may find yourself working to catch your breath in hot weather. That’s because breathing in hot air can cause narrowing of the airways (bronchoconstriction). When airways are tighter, you may start to wheeze, cough, and struggle to breathe, similar to an asthma attack.
Humidity increases the risk of bronchoconstriction in warm weather, especially for people with existing respiratory conditions like asthma and chronic obstructive pulmonary disease.
High temperature can cause “lung sunburn”
Similar to how unprotected exposure to the sun damages skin cells and causes sunburn, prolonged exposure to heat and air pollution damages the lungs. “Lung sunburn” occurs when ozone, an air pollutant worsened by heat, causes lung irritation and inflammation.
“It’s not like a direct burn on the lung,” Angela Tin, board member of the Illinois Pollution Control Board, told the Indianapolis Star in 2023, when she led the American Lung Association’s Clean Air Initiative. “It’s high heat causing high ozone and then prolonged exposure can affect the lungs.”
Warmer temperatures worsen allergies
Climate change has led to higher levels of pollen and longer allergy seasons, contributing to lung irritation and breathing problems.
“Climate change fuels a perfect storm of conditions that make allergy season worse for people with pollen allergy,” said Kenneth Mendez, president and chief executive officer of the Asthma and Allergy Foundation, in a 2024 statement.
“Now, we see both more days of exposure to pollen and higher daily pollen counts leading to more intense, longer-lasting symptoms.”
Around a quarter of adults and a fifth of children in the United States have seasonal allergies, most caused by pollen.
Extreme temperatures worsen existing lung issues
Many factors intensified by climate change—heat, humidity, pollen, air pollution—can also worsen respiratory diseases like asthma and chronic obstructive pulmonary disease. Extreme heat and pollution can trigger flare-ups of both conditions and worsen symptoms like shortness of breath.
Notably, extreme cold can also trigger lung conditions. Like hot air, cold air can cause irritation and narrowing of the airways. Cold weather is also associated with a rise in respiratory viruses like the cold and flu, which can be particularly dangerous for people with existing lung issues.
How to keep your lungs safe in the changing climate
Monitor local weather and air quality: The CDC’s HeatRisk tracker allows you to monitor local heat and air quality conditions and offers tips to stay safe based on your zip code. Additionally, AirNow.gov provides real-time air quality alerts through EnviroFlash, an automated email and text message notification system.
Be aware of individual risks: According to the American Lung Association, those who are at increased risk from high heat include “outdoor workers, the elderly, children, pregnant individuals, individuals with pre-existing health conditions (including people with lung disease), people experiencing homelessness, individuals living in manufactured [mobile] homes, and those living in low-income communities.”
Have a plan to stay cool: Take steps to protect against extreme weather and air quality conditions that can harm your lungs. Stay indoors if possible, and drink plenty of fluids. If you don’t have access to air conditioning, find a cooling station. If you have to go outside, wear loose-fitting and light-colored clothing, stay in the shade, and avoid strenuous physical activities.
For more information about lung health in any weather, talk to your health care provider.