Wildfires are making the US smoggy again, reversing progress on cleaner air, study finds

Wildfires since 2015 have reversed a decade-long decline in U.S. smog levels, increasing ground-level ozone by 4% and contributing to an estimated 318 annual deaths. A University of Iowa study used AI to analyze limited EPA smog monitor data, revealing the trend reversal despite prior human-caused emissions reductions.