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.

Explore the Data

Areas of Focus: Environment
Definition
Environment
Producing and using energy damages people’s health and the environment. EPIC research is quantifying the social costs of energy choices and uncovering policies that help protect health while facilitating growth.
Air Pollution
Definition
Air Pollution
Air pollution from fossil fuel combustion poses a grave threat to human health worldwide. EPIC research is using real-world data to calculate the effects of air pollution on human health...
Clean Air Program
Definition
Clean Air Program
The Clean Air Program works to bring actionable air pollution information, its impact on our health, and effective policy solutions to communities around the world.
AQLI
Definition
AQLI
Particulate air pollution is one of the most serious risks to human health globally. To help communicate those risks, the Air Quality Life Index (AQLI) converts particulate air pollution into...