Wildfire smoke has reversed US progress toward ozone air quality, study finds

Article excerpt

Wildfires have erased a decade of American progress in reducing ground-level ozone, according to research published Thursday in Science. Since 2015, the blazes have pumped enough pollution into the atmosphere to undo years of regulatory gains, creating a crisis that public health officials say is far more severe than previously understood. The fires have already been linked to tens of thousands of premature deaths across the US and North America, but their air-quality damage extends well beyond those casualty counts, they've essentially handed back all the ozone reductions that environmental regulations fought hard to achieve.