NASA study: Wildfire smoke worsens ozone pollution, erasing years of air quality gains across US

A NASA-supported study published in Science found that wildfire smoke has significantly worsened ground-level ozone pollution across much of the contiguous United States over the last decade. Researchers used deep learning to analyze data from 2003 to 2024, finding that wildfires offset nearly four years of ozone-control progress nationally, with larger setbacks in the West and Midwest. The study showed that after 2015, gains from reducing ozone-forming pollutants slowed or reversed in many areas due to wildfire contributions. In the Midwest alone, wildfires erased about 5.3 years of progress since 2015. The 2023 Canadian wildfires demonstrated how smoke can travel thousands of miles, with ozone increases stretching across the Midwest into the Northeast and South. Researchers estimated that wildfire-driven ozone contributed to an additional 318 premature deaths per year after 2013, a 46% increase over the previous decade. From 2022 to 2024, wildfires exposed an extra 43 million Americans to conditions failing federal air quality standards for ozone. The team developed FireAQ, a decision-support system using satellite data to help officials track smoke-related pollution during fire season.