Smoke & Air Quality
Smoke & Populations
[from the text] The danger of catastrophic wildfires is increasing around the globe, with large fires occurring in Australia, Canada, Chile, Indonesia, Portugal, Russia, as well as in the United States over the past decade. A major driver globally is climate change, which is expected to increase the frequency and severity of wildfires because of drier fire seasons, warmer temperatures, reduced precipitation, and snowpack. Large forest fires in the western United States have been nearly 5 times as frequent on an annual basis as they were 50 years ago. These fires are burning more land area (Fig. 1) and requiring multi-week or month fire suppression campaigns. The wildfire season has also become much longer, as exemplified by the severe fires in California during November and December 2018 to 2019. The wildfire season in California typically ended in October when autumn rains began, but there has not been sufficient rain to prevent wildfires in the fall months when high winds occurred for the last several years.