As I looked west from Vancouver Island last summer, the sunset wasn’t the brilliant orange I’d expected but rather a muted crimson smudge – the telltale sign of wildfire smoke already pushing across hundreds of kilometers of forest and mountain. For communities like Toronto, sitting thousands of kilometers from active fire zones, such hazy intrusions can seem bewildering. Yet they’ve become increasingly common.
The atmospheric river of smoke that’s expected to reach Toronto this week follows a now-familiar pattern. Environment Canada meteorologist Gerald Cheng confirmed yesterday that wildfire smoke from Saskatchewan and Manitoba has already begun its journey eastward, with air quality expected to deteriorate noticeably by Wednesday.
“We’re looking at particulate matter concentrations potentially reaching the ‘moderate risk’ category on the Air Quality Health Index,” Cheng explained during our phone conversation. “It won’t be as severe as what we witnessed last summer, but sensitive groups should still exercise caution.”
Last June, Torontonians woke to apocalyptic orange skies as smoke from Quebec wildfires blanketed the city, pushing the Air Quality Health Index beyond 10 – the highest possible rating. School recesses were canceled, outdoor events postponed, and N95 masks became a common sight on downtown streets.
Dr. Sarah Levitt, a respirologist at Toronto General Hospital, has observed the health impacts firsthand. “After these smoke events, we typically see a 20 to 30 percent increase in emergency department visits for respiratory complaints,” she told me when I visited her clinic last month. “It’s not just people with pre-existing conditions either – healthy individuals report headaches, irritated eyes, and difficulty breathing during prolonged exposure.”
The science behind smoke’s continental journey is relatively straightforward. When massive wildfires generate intense heat, they create their own weather systems that can push smoke particles high into the atmosphere. Once aloft, these microscopic particles – many smaller than 2.5 micrometers, known as PM2.5 – can travel thousands of kilometers on prevailing winds. Upper-level jet streams can transport this smoky cargo across provinces and even international borders before it eventually descends.
What’s changed is the frequency and intensity of these events. A 2023 study published in Environmental Research Letters found that Canadians’ exposure to wildfire smoke has increased by approximately 40 percent over the past decade. Climate scientists attribute this rise to warmer temperatures and changing precipitation patterns that create more favorable conditions for forest fires.
For Maria Constandinou, a mother of two in Toronto’s east end, these smoke events have necessitated new family protocols. “We invested in HEPA air purifiers after last summer,” she said while watching her children at Withrow Park. “I keep a close eye on the air quality app now, just like I check the weather. We’ve had to cancel soccer practices and birthday parties because of air quality warnings.”
The City of Toronto has enhanced its response capabilities following last year’s smoke crisis. Public health officials now maintain a specialized wildfire smoke response plan that includes alert systems for vulnerable populations, coordination with school boards, and expanded clean air shelter capacity.
“We learned valuable lessons last summer,” acknowledged Dr. Vinita Dubey, Toronto’s Associate Medical Officer of Health. “Our primary message to residents is to stay informed and prepared. When air quality deteriorates, limit outdoor activities, keep windows closed, and use air conditioning if available.”
Indigenous knowledge keepers note that while wildfires have always been part of North American forest cycles, their character has changed dramatically. “Our Elders talk about controlled burning as medicine for the land,” explained Clayton Shirt, an Anishinaabe fire keeper I met during a ceremony near Georgian Bay last month. “But what we’re seeing now – these megafires burning hotter and spreading faster – this is the land in distress, responding to how we’ve managed forests and changed the climate.”
Environment Canada predicts this week’s smoke event will last approximately 48 to 72 hours before a weather system pushes the haze northeastward. While it’s expected to be less severe than previous episodes, health officials still recommend that children, seniors, pregnant women, and those with heart or lung conditions take precautions.
Dr. Levitt suggests keeping indoor air as clean as possible during smoke events. “Beyond keeping windows closed, limit activities that generate indoor pollutants like cooking without ventilation or burning candles,” she advised. “If you must go outside, a properly fitted N95 mask offers significant protection against fine particulate matter.”
As I watch the forecast maps showing the smoke’s eastward progression, I’m reminded of conversations with fire ecologists who emphasize that these events represent our new reality. The interconnectedness of our continent’s airshed means that fires burning in remote forests increasingly affect population centers thousands of kilometers away.
For Torontonians preparing for this week’s hazy skies, the smoke serves as a distant but tangible reminder of our changing climate – and the growing need for both personal adaptation and broader systemic change.
