WASHINGTON, D.C. — A new report has found that large-scale, climate-fueled wildfires are reversing decades of progress in improving air quality across the United States. The study, published by the University of Chicago’s Air Quality Life Index (AQLI), highlights a concerning trend: smoke from increasingly intense and prolonged fires is negating the gains made by landmark environmental policies like the Clean Air Act, posing a significant risk to public health. The report concluded that wildfire smoke has undone roughly 25 percent of the country’s clean air improvements since the year 2000.
The Hazy Truth about Air Pollution
The primary threat from wildfire smoke is fine particulate matter, known as PM2.5. These microscopic particles can travel hundreds or even thousands of miles and, once inhaled, penetrate deep into the lungs and even the bloodstream. This can lead to a host of serious health problems, including respiratory issues like asthma and bronchitis, as well as cardiovascular events like heart attacks and strokes. The AQLI report states that the impact of particulate pollution on life expectancy is comparable to that of smoking.
The report noted a sharp increase in unhealthy air days in 2023, particularly in the Midwest and East Coast, which bore the brunt of smoke from Canada’s record-breaking fire season. For the first time in a decade, counties in Ohio, Wisconsin, Pennsylvania, and Illinois replaced California counties as having some of the most polluted air in the nation. The findings underscore how a regional environmental problem can quickly become a widespread public health crisis due to climate-driven weather patterns.
Michael Greenstone, the University of Chicago professor who created the AQLI, emphasized the direct link between human activity and the current crisis.
“It’s correct to think of this air pollution from the wildfires as, kind of, the ghost of fossil fuels past,” Greenstone told CBS News. “The point we’re trying to make is that CO2 that’s released when we use fossil fuels, both historically and today, it stays up in the atmosphere for centuries, and it raises temperatures… What we’re seeing is an important consequence of that, which is, it’s going to increase the incidence of wildfires going forward.”
A Reversal of Progress
For more than half a century, the U.S. has made remarkable progress in cleaning its air, largely through the implementation of the Clean Air Act and regulations on industrial emissions and vehicle pollution. According to the U.S. Environmental Protection Agency (EPA), these efforts have led to significant reductions in criteria pollutants, improving public health and life expectancy. However, the new AQLI study demonstrates that this progress is being undermined by a new source of pollution: climate-fueled wildfires.
The increase in wildfire-related PM2.5 is particularly concerning because it is difficult to control. Unlike industrial emissions from a factory, which can be regulated, the spread of wildfire smoke is dictated by wind and weather, making it a challenging public health issue. The EPA and other agencies provide real-time air quality data and health recommendations through the AirNow program, but these measures can only help people protect themselves, not address the root cause.
Scientists and environmentalists are calling for a two-pronged approach to address the issue: more aggressive action to combat climate change, which is driving the fire intensity and frequency, and better forest management to reduce fire risk. As the planet warms, hotter, drier conditions are making landscapes more susceptible to large-scale fires, a feedback loop that continues to worsen air quality and put more people at risk. The new report serves as a stark warning that without a concerted effort to address climate change, the health of millions of Americans will continue to be compromised by the “ghost of fossil fuels past.”