News and stories Based on Science Does global warming cause breathing problems?

Does global warming cause breathing problems?

Based on Science

In many regions, the warming climate is making air quality worse. Poorer air quality contributes to or may cause breathing problems and respiratory illnesses.

Health and Medicine

Pollution

Climate Change

Last update January 11, 2022

Global warming has been associated with an increase in the frequency of ground-level ozone episodes, leading to breathing problems.

Ozone is a gas made of three oxygen atoms joined together. When it forms high up in Earth’s atmosphere, it creates an ozone layer that shields us from some of the sun’s ultraviolet rays. But ozone can also form near Earth’s surface when sunlight drives reactions between certain gases in the air, namely, nitrogen oxides (NOx) and volatile organic compounds (VOCs). NOx and VOCs come from car exhaust, wildfires, and other sources.

Breathing ozone irritates the lungs and the rest of the respiratory system, leading to shortness of breath. It can also cause inflammation and make the lungs more susceptible to other triggers of inflammation, such as pollen and mold spores, sometimes leading to infections. Spikes in ground-level ozone are linked with increased hospitalizations for chronic obstructive pulmonary disease (COPD), pneumonia, asthma, allergies, and other lung problems. They are also associated with premature death. Long-term exposure to ozone is particularly linked with COPD. Globally, 11 percent of deaths from COPD in 2019—365,000 deaths—were associated with ozone exposure.

When it is warmer and sunnier, the chemical reactions involving NOx and VOCs speed up, creating more ozone. And warmer weather is often associated with more stagnant air, so on hot days people can be exposed to ground-level ozone for longer periods of time as the polluted air accumulates. In many regions, global warming leads to an increased risk of exposure to episodes of ground-level ozone.

Some extreme weather events create air pollution.

Droughts and wildfires are becoming more common in some locations as the climate warms, and these types of extreme weather events contribute to air pollution by increasing the amount of small particles in the air (called particulate matter) that can be inhaled. Droughts create conditions that are favorable for dust storms, which reduce air quality by increasing the amount of particulate matter in the air. Additionally, particulate matter can stay in the air during dry spells because there is less rain to remove them from the atmosphere. The particulate matter can irritate the airways of people who suffer from respiratory illnesses.

Dry, hot conditions are also conducive to the start and spread of wildfires and to longer wildfire seasons. Smoke from wildfires―which creates particulate matter, ozone, and other toxic gases and chemicals―has been linked to shortness of breath, asthma, and COPD. It has also been associated with premature deaths and low infant birth weight. Smoke can travel hundreds of miles, so the health effects from poor air quality can affect people far from the location of the fire.

Longer growing seasons and increased pollen production caused by global warming contribute to seasonal allergy suffering and asthma attacks.

With warmer temperatures and more carbon dioxide in the air, plants may produce more pollen, grow in more locations, and flower over a longer growing season. For example, the pollen production season for ragweed—the most common allergy-inducing plant in the United States—increased by 11–27 days in parts of the central U.S. and Canada between 1995 and 2011.

Longer growing seasons or greater volumes of pollen production mean people are exposed to more pollen in the environment. While it is not the only reason why people develop allergies or asthma, pollen exposure can increase the chance of developing hay fever or having an asthma attack. Research also suggests that there are interactions between pollen and air pollutants, such as ground-level ozone, NOx, and fine particulate matter, that make allergy suffering or asthma attacks more severe, more frequent, or both.

Certain people are especially vulnerable to these health effects.

The health toll of poor air quality is uneven across countries and societies. People living in less developed countries and in cities throughout the world tend to have the most polluted air. Wealth, distribution of income, public health infrastructure, and access to medical care affect the severity of the effects, but in any country, young children, older adults, and people with existing health problems face the highest health risks from poor air quality.

There are steps that you can take to reduce breathing problems from poor air quality.

Federal, state, tribal, and local governments in the United States collaborate to monitor and map air quality. They publish this information daily as the Air Quality Index (AQI). The AQI has six levels of concern to rank when outdoor air quality is hazardous to the health of different populations. By using the AQI to learn when outdoor air quality is poor in your area, you can stay inside and reduce your exposure to hazardous conditions.

The National Allergy Bureau provides the only certified pollen and mold counts in various portions of the United States, which can assist in providing information about the types and amount of pollen in your area.

In the longer term, there are steps we can take to reduce global warming and its impacts on society—including breathing problems from poor air quality—which begin with cutting back on greenhouse gas emissions.