The average annual amount of acres burned has been steadily increasing since Gleason, who conducted the research as a postdoctoral fellow at the Desert Research Institute, and her team cite two reasons for the earlier snowmelt. By increasing the concentration of airborne particulate matterwildfires can heighten the risk of lung disease, heart disease, and diabetes.
In San Francisco after the Camp Fireparticulate concentrations were 60 times the safe level, prompting school closures.
Acres burned in these U. Sincewildfires have shifted from burning shrub-lands to burning conifers. Arienzo, Nathan Chellman, Wendy M. Carbon released to the air adds to the burden of greenhouse gases already there, thus producing even more warming.
The study does not cover western grasslands. The number of megafires—fires that burn more thanacres square miles —has increased in the past two decades. But how have wildfire occurrences changed over the decades?