Air Quality is increasing due to a changing environment. A changing environment means higher air temperatures and changing humidity, which in turn impact wildfire activity and ozone formation.
Increasing wildfire activity creates more smoke
As the atmosphere warms, so do surface temperatures that affect the rate of evaporation in dense wilderness areas. Longer dry spells and lowered humidity also contribute to the drying out of vegetative fuel layers necessary for large wildfires. As soil and vegetation dry more quickly and more completely than in past seasons, wildfires are able to ignite more easily and get out of control more rapidly. This leads to more large fires that emit fine particulate matter (PM2.5) that negatively impacts air quality and threatens human health.
The ‘climate penalty’ of ground-level ozone
Ozone has what is referred to as a ‘climate-penalty’, where surface levels increase due to shifting meteorological conditions that are conducive to ozone formation. High temperatures, low humidity, and their contributions to moisture balance or vapor pressure deficit are all well documented to promote increased ozone levels. High temperatures speed up the chemical reactions that form ozone and can cause local vegetation to release more ozone precursors, such as isoprene. Low levels of humidity can extend the lifetime of ozone (while high humidity promotes ozone depletion), and vapor pressure deficit directly modulates the uptake of ozone by trees through the opening and closing of stomata. Learn more