Tens of thousands of people have been forced to flee their homes as forest fires rage across the country, sending a smoky haze billowing across much of the U.S. 

Approximately 4.3 million hectares (10.6 million acres) of land have already burned, which is roughly 15 times the annual average over the last decade. Warm, dry weather is expected to persist in the coming months. Currently, over 400 wildfires are burning across Canada, with over 200 of them deemed "out of control."

The fires have impacted mining operations in Canada and disrupted flights in the United States. On Thursday, the Toronto District School Board, Canada's largest, rescheduled or moved indoors all outside activities, including field trips and local school events.

Although wildfires are common in Canada, it is unusual for blazes to be burning simultaneously in the east and west, stretching firefighting resources, forcing the government to send in the military to help, and fueling concerns about the worsening consequences of climate change.

The U.S. has sent hundreds of firefighters to Canada over the past few weeks and has said more help is on its way. Canadian Prime Minister Justin Trudeau, who thanked Biden for U.S. help in a call on Wednesday, has blamed climate change for the unprecedented early-season wildfires.

South Africa, Australia and New Zealand have also offered assistance. According to European Commission President Ursula von der Leyen, France, Portugal and Spain are also sending more than 280 firefighters to Canada.

The wildfire season started unseasonably early in Alberta last month and burned a record area, and Nova Scotia continues to battle its largest-ever blaze. The flames have eased in Alberta, the center of Canada's oil and gas industry. However, more than 3,000 people remain under evacuation orders, and heat warnings are in effect in the south of the province.

(With input from Reuters.)

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