health
Wildfire smoke has reversed US progress toward ozone air quality, study finds
Since 2015, fires have undone years of effort to reduce ozone levels, underscoring a growing public health crisis

TL;DR
- 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.