Wildfire smoke could lessen air quality around Ottawa

A haze of smoke is possible this week as strong winds and wildfires in the west push smoke toward eastern Ontario and western Quebec.

Wildfires have been raging in Alberta, Saskatchewan, Manitoba and northern Ontario, forcing thousands of people out of their homes and causing air quality warnings from northern B.C. to Thunder Bay.

Environment Canada is predicting an Air Quality Health Index risk of 4 or moderate for Tuesday and Wednesday in local hubs Belleville, Cornwall, Gatineau, Kingston and Ottawa.

People at high risk — such as those with lung conditions or who are very young or very old — should consider rescheduling outdoor activities if they experience symptoms.

According to warning preparedness meteorologist Geoff Coulson, it won't be enough to issue an air quality statement, but it could be noticeable. 

"It certainly looks like the sunshine could be fairly hazy," Coulson said.

Environment Canada issues air quality statements when concentrations of particulate matter are above 60 micrograms per cubic metre. He expects it will fluctuate locally between 10 and 50 over the coming days.

In 2023, the Air Quality Health Index for Ottawa reached 10+, the top of the scale. Environment Canada is not yet predicting the same level of risk.

"This could still be a concern as we go to the end of the work week and into the weekend, so [it's] obviously a situation that the forecasters will be monitoring closely."

A high air quality risk means at-risk people should scale back strenuous outdoor activities, while others should watch for symptoms and adjust accordingly.

Those very high risks seen two years ago mean people should try to avoid strenuous outdoor activities, especially those with health conditions.

Fires create a perfect storm

Meteorologists say the situation to the west could get worse: escalating fires can raise temperatures, which can cause stronger winds, causing fires to spread farther. 

"It's kind of a positive feedback loop situation," climatologist Tanzina Mohsin told CBC Radio's All In A Day on Monday.

Those winds, according to Environment Canada, can also push smoke and other pollutants elsewhere.

An early start to the wildfire season, along with a lack of rain in areas affected by the fires, have contributed to their strength, she said.

As the fires continue, Environment Canada encourages residents to monitor the air quality forecast and take measures to protect themselves if they are at risk or conditions worsen.