The Swiss air quality tracker IQAir says at one point on Wednesday Toronto had the world’s worst air quality. The city was later joined by Chicago and Detroit as smoke and haze from wildfires drifted south. The haze almost obscured Toronto’s skyline.
As it did earlier in June, the smoke has led to a number of closures and cancellations. People with respiratory issues are being warned to stay indoors.
“As of today there are 67 wildfires ongoing in Ontario and a number of those are not anywhere near being under control," said Steve LaForet, fire chief of Windsor. "One or two rains are not going to make the environment bounce back. It takes a long time and a lot of water to make things moist and resistant from fires.”
More than 70 fires are also burning in northern Quebec adding to the haze.
The smoky conditions have also spread to the U.S., including the Great Lakes area, and as far south and west as Missouri and Kentucky.
The Environmental Protection Agency listed Detroit’s air quality as "hazardous." The smoke has also drifted into New York, southern Illinois, Indiana, and Ohio. The haze has even reached as far as Europe, but air quality there has not been affected as much as in North America.
President Joe Biden has said the wildfires in Canada are clear evidence of climate change.
Environment Canada says air quality will improve for some areas of Ontario and Quebec Thursday night but in some regions, the unhealthy air is expected to last for days.