As record wildfires raged in areas around the world this summer—from Greece to Canada to Indonesia—California’s consistent exposure to wildfire smoke is proving its deadly toll. AQLI’s most recent report shows that out of the top 10 most polluted U.S. counties, 9 of them were in California in 2022.

Residents of California’s Central Valley are now consistently exposed to average particulate pollution (PM2.5) levels above both the WHO guideline and the nation’s own air quality standard. The most polluted county in California in 2022 was Kern County, where residents stand to gain 8.4 months if the WHO guideline was met. As the planet becomes hotter, drier soil and drought conditions expose more areas to wildfire risks. As this past wildfire season proved, California is not the only home to rampant wildfires. They have run rampant in regions throughout the world, from Canada and Greece to Indonesia and the Congo Basin. Each wildfire brings a surge in PM2.5 levels, exposing the communities near them to harm. Given the role climate change will play in exacerbating air pollution, with an increase in extreme wildfires being a poignant example, it is imperative that policies continue to be introduced to reduce the burning of fossil fuels.