Wildfire smoke has reversed US progress toward ozone air quality, study finds Recent research indicates that destructive wildfires have significantly increased emissions and led to tens of thousands of premature deaths, with their impact on air quality being greater than previously understood. Since 2015, these fires have reversed US progress toward ozone air quality standards, as worsening pollution from wildfire smoke has undone years of efforts to reduce emissions. The study highlights that mitigating climate change and implementing fire prevention measures are crucial steps for improving air quality and public health.

• Wildfires have significantly increased emissions and are linked to tens of thousands of premature deaths.
• Since 2015, wildfires have reversed US progress toward ozone air quality standards, undoing years of emission reduction efforts.
• Wildfire smoke contributes to ground-level ozone formation and can increase ozone levels hundreds of miles away.
• Despite reductions in human-caused ozone precursor emissions, surface ozone levels have plateaued, correlated with wildfire emissions.
• The study found ozone levels shifted from decreasing by 0.65 parts per billion (ppb) per year before 2015 to rising 0.13ppb annually after that year.
• Wildfire emissions are correlated with an estimated 318 premature deaths annually since 2013.
• The US Environmental Protection Agency’s monitoring stations cover only 2% of land in the continental US, necessitating new data analysis methods.
• Global heating is leading to more frequent and destructive wildfires worldwide.
• Wildfire smoke contains PM2.5, a pollutant linked to numerous health conditions and premature death.
• Addressing the climate crisis is presented as an important step to reducing pollution caused by wildfires.