YELLOWKNIFE - The Northwest Territories is bracing for another hot wildfire season as a new report details last year's record-breaking burns.
"It's grim," Environment Minister Michael Miltenberger said. "This year could be as bad or worse than last year.
"It's hopefully not a precursor for the new normal."
According to the fire season report released Tuesday, about 3.4 million hectares of forest burned last year in the N.W.T.
That's an area more than five times the size of Toronto and almost twice the average annual burn for all of Canada. At their worst, the fires were spreading at nine kilometres an hour, the speed of a brisk jog.
The situation was so bad that some firefighters had to work 19 days without a break. Air quality in Yellowknife was below standards for much of July. The territory's firefighting budget had to be increased eightfold.
Scientists tracked the ash around the world.
"All the weather indicators tell us there hasn't been a huge improvement," Miltenberger said.
The southern end of the territory didn't get much rain last fall or yet this spring. The winter snowpack is gone. Drought indexes are the worst they've ever been.
It's part of a pattern across North America as climate change takes hold, said Mike Flannigan, a University of Alberta scientist who's been studying those impacts for more than a decade.
"We are having more fires because of human-caused climate change," he said.
Temperatures in the N.W.T. are rising faster than almost anywhere else on Earth. Warmer temperatures extend the fire season, cause more lightning and dry out the forest — all factors that increase the risk.
But Flannigan said some scientists believe climate change has created new weather patterns that also favour wildfires.
As climate change reduces the temperature gradient between the Arctic and mid-latitudes, the strength of a high-altitude river of air called the jet stream fades. Several published papers have argued that causes the jet stream to stray from a straight west-to-east path to wobbling up and down the continent.
When that happens, weather patterns can get stuck in place. Last summer, the N.W.T. got stuck with a high-pressure ridge that lasted weeks and consistently pushed warm, dry air out over the forest.
"I don't care how much rain you've had, if you give me a week of upper-ridge warm dry weather, you can have a fire problem," Flannigan said.
"Fire is driven by extremes. If we see more extremes because of this meandering jet stream, we're going to see a lot more fire."
Miltenberger said the territory is changing its approach to firefighting.
It plans to increase its public communications and safety procedures. It will revamp its operations to ensure a firefighting effort can expand quickly to meet a growing threat.
The report suggests crews could attack fires at a much earlier stage to prevent them from getting out of hand.
It's a new world, said Miltenberger.
"It's a world where some of the old rules don't apply and you have to be very aware and quick and nimble and be prepared to address your strategy. The strategies of old may not apply."
— By Bob Weber in Edmonton. Follow him on Twitter at @row1960.