Canada fires prompt US air quality alerts as smoke blankets major cities

In Canada, one fire in northern Ontario forced residents from local First Nations to evacuate, with one chief saying that her community has been "burnt to ashes". There are currently 858 fires actively burning in Canada, including 30 new fires on Thursday, according to the Canadian Wildland Fire Information System.

The vast majority are burning out of control.

The large cluster of fires affecting northwestern areas of Ontario are responsible for sending thick plumes of smoke and poor air quality across Thunder Bay and Toronto, with lower concentrations of smoke high in the atmosphere drifting over the Great Lakes and above New York with hazy skies and redder sunrise and sunsets likely.

The far-reaching impacts of wildfire smoke – and how to protect yourself In western regions of New York state, the air quality on Thursday is considered "very unhealthy", while in the New York City metro area the air quality is "unhealthy".

New York has extended its heat emergency plans and activated its air quality emergency protocols - with hundreds of cooling centers and KN95 masks being made available citywide. In Ontario, there will be quite widespread thunderstorms over the next few days, but the rain may not be enough to make much of a difference.

Air quality in the Midwestern city of Detroit is currently the worst in the world, Swiss air quality tracker IQAir said, followed by Minneapolis, Chicago and Toronto.

Republican lawmakers in the state of Michigan have penned an open letter , external to Canadian Prime Minister Mark Carney asking for better management of the country's wildfires, expressing frustration for a third year in a row.

"A year has passed, the season has come around again, and nothing has changed except that our patience has run out," said the letter, signed by four state House representatives .

Wildfires are a part of the natural life cycle of Canada's vast boreal forest, but they have become more frequent since 2015, said Laura Chasmer, a professor of geography and the environment at the University of Western Ontario.

"This is associated with some of the extreme climate warming that we've been seeing, and the atmospheric drying of the surface," she said.

Fires in the past burned more frequently in western Canada, but recent years have seen that trend migrate eastward, with large fires now burning in Ontario, Quebec and Atlantic provinces, Prof Chasmer said, leading to more noticeable smoke in densely populated cities like Toronto and New York.

She added that this has strained firefighting efforts in Canada, whose primary focus is to ensure the flames don't spread to nearby towns. Putting out the fires completely is "very difficult", Prof Chasmer noted, due to their scope and intensity.

He added his government is "in close communication" with provinces and local communities. Meanwhile, Ontario Premier Doug Ford dismissed criticism of his government's handling of the fires, noting that over 150 fire crews are on the ground battling the blaze. "We will spend whatever it takes," Ford said.

In addition to the hazardous smoke, the wildfires in northern Ontario have forced dozens from local First Nations communities to evacuate, with videos showing some fleeing the remote area by boat.

Namaygoosisagagun First Nation Chief Helen Paavola told local news outlet CityNews in an interview that an aerial flyover showed that her community has been "burnt to ashes". "All the homes are gone," she said on Thursday. "There's nothing left."

America's blame game over Canada's wildfire smoke misses the point, experts say