Smoke from wildfires in Canada has engulfed the East Coast, cloaking cities in a hazy smog and putting some 100 million people under air quality alerts. More than 400 fires are burning in British Columbia, Alberta, Quebec, and Ontario, and half are uncontrolled. New York City became home to the worst air quality in the world. Philadelphia has also issued a code-red alert, advising people to stay indoors, and the plumes may continue inundating the region for several more days to come, with the smoke stretching through Washington, DC, and down to Atlanta, Georgia.
In the United States, supercharged wildfires once seemed like a uniquely West Coast problem, like the 2018 Camp Fire which obliterated the California town of Paradise. A range of factors contributed to that massive blaze, including the region’s legacy of fire suppression, which allowed dead brush to pile up. Climate change means that hotter temperatures dry that brush out, so it burns catastrophically. That’s also the problem in Canada right now. The number of fires is only slightly above the average for this time of year, but “the size of the fires and the intensity of fires has significantly increased,” says Mike Flannigan, a professor of wildland fire at Thompson Rivers University in British Columbia.