As Canada burns, author of ‘Fire Weather’ sees the nation’s hotter future

John Vaillant: So much of the country is forested, and the country is so vast. We have to keep in mind … Canada is the second largest country — by area —in the world. And so the fires really burn on a different scale … you know, these can burn a thousand square miles and not even make the news.

There are so many downsides to climate change, but as the atmosphere warms, it actually generates more lightning. My understanding is with every degree of warming, you get about 12% more lightning. So, you can have very remote areas in Alaska or the far north of Canada where there are simply no human beings whatsoever, and many fires can be started there by lightning. But most fires, especially around settled [or] inhabited areas, about 80% of those fires are human caused, which means a carelessly managed campfire, a hot muffler, a spark coming off a chain … you know … hanging off a bumper on the road and flying into the dry grass. We are a flamboyant species and we have a lot of fire around us all the time and they get out of control.

Almost all fires start small and it really depends on the weather conditions.

Boreal forests, the northern forests of Canada and Alaska, are really the wettest biome on earth. In spite of that, the weather conditions for Fort McMurray, Alberta on May 2016, the relative humidity was 11%. You have to go to Death Valley in the month of July to find a comparable relative humidity. So, [you] find desertic dryness in the northern boreal after two years of drought. And then you break the temperature record for that day and put it up into the 90s. And then, you set it on fire.

Even with water bombers on it, almost immediately burned out of control. And once the heat starts billowing out of that fire, it starts generating its own wind and it starts throwing the embers. But [then] you have radiant heat, which is the invisible heat that tells you not to touch the candle; it moves at the speed of light. And the radiant heat coming out of this wall of flame sweeping into Fort McMurray was about 900 Fahrenheit. So that’s hotter than the planet Venus. And what that does is not only does it generate more wind, it desiccates everything in front of it for many hundreds of yards. So every tree, every house, everything is bone dry and then heated up past combustive temperatures. So, the moment an ember lands on it, again, it doesn’t just sizzle, it explodes into flame.

There’s a cumulative effect to climate change. We had the hottest year in recorded history in 2024 … 2023 was almost as hot as that. And as you raise the temperature of anything, you’re going to have more evaporation.

So, we’ve got four, or potentially five more months, of fire season for Canada. We’re really just getting started and we’re also just heating up. And we haven’t had proper snow pack in years. Rivers, bogs are all evaporating much more quickly than they normally would, and so all kinds of water levels are at record lows across western Canada. And, again, that just exacerbates the situation. You have this compound effect. And here’s quite an interesting detail … Maybe you’ve heard of zombie fires, also known as holdover fires.

It’s new to human observation. Mike Flanagan, a very well-respected fire scientist here in western Canada, has observed this, and he said, ‘You know, I’ve been studying this phenomenon since the 1970s, and I’ve never seen them make it through two winters.’ And so what you have then is this potential future scenario where there’s no longer a fire season. There’s just fire.

They’re burning almost like a coal seam fire, kind of perpetually smoldering underground. Think of the roots down there as these slow-burning fuses, and they just burn all winter long, and then when the snow cover is gone and the frost is gone, they can resurface to light up the duff, leaves and grass above them, and then move into the trees.

One of the really heartening byproducts of these fires is this incredible community response. When Fort McMurray was evacuated, almost 90,000 people were run out of there in an afternoon. It was the biggest, most rapid evacuation due to fire in modern times. And the rest of Canada opened their arms to those people. But when it keeps happening, it’s very taxing to the finances, to the social capital, to just the toothpaste supplies in local stores, when thousands of new people suddenly descend on a community. And while people are generous and helpful, there are limits.

[High Level, Alberta] has officially announced that they won’t be taking in fire refugees this season because they’ve done it for the past couple of seasons and it’s a small community, they don’t have a lot of margin. They’re basically saying we can’t handle it anymore. And it’s not because they’re selfish or don’t love their neighbors. It’s simply because their resources are exhausted. It’s also physically exhausting, looking after hundreds if not thousands of new people who might be traumatized, are certainly disoriented and need everything, because they’ve left everything behind.

This is another terrible test that climate change is imposing on us. We can handle disasters most of the time. But what we don’t do so well is serial disasters. They’re a terrible drain on every kind of resource. And they’re so demanding and so violent. And then there’s the trauma … that needs to be counted in terms of when we tally the costs of these events.

… I don’t think it’s about the warning system, but exit routes are a real issue. Many modern housing developments are built with only one road in and one road out. And if that road is compromised by fire and there isn’t an alternate route, people can become trapped. That’s a real issue in many Canadian communities, and I’m quite sure it is in many American communities, especially western ones.

When you look at where we were this time of year in 2023, we’re in that same place. We’ve burnt a colossal amount of area. Last count I heard was a couple of million acres. The smoke billowing out of the nation right now, and unfortunately, in the United States and across the Atlantic, is also record breaking. So we could have potentially a worst fire season than 2023, which was the worst in Canadian history. And there’s nothing to suggest that shouldn’t happen when you look at the fact that the world is hotter.