Fires rage this past May in Slave Lake, Alta., where 7,000 people had to flee as the inferno raced into town. The forest-fire season has been starting earlier and lasting longer in recent years.
Wildfires, which already burn more than 350 million hectares globally causing an estimated 340,000 deaths, will double in number in the near future, leading forest-fire experts have warned.
And the northwest could be hit the hardest, with some projections saying British Columbia and Alaska will have five or six times as many fires, says Mike Flannigan, a professor of renewable resources at the University of Alberta and senior research scientist with Natural Resources Canada.
"A warmer world's going to see more fires," Dr. Flannigan said during a presentation at the American Association for the Advancement of Science annual conference in Vancouver this weekend.
Dr. Flannigan, an expert on fire and the potential impact of climatic change, said not only will there be more fires in the future – but they will be more intense too, with many being too big and too hot to stop using traditional fire fighting methods.
"It's going to be incredibly difficult in the future to manage forest fires because the intensity of forest fires is going to be increasing," he said.
"If a fire is intense, you cannot attack the head of the fire: You have to attack the flanks. If a fire is intense, aerial suppression is no longer effective, so even modern fire management agencies, like Canada, the United States and Australia, among the best in the world will be extremely challenged, and I would argue that the standard way of doing fire management will no longer be effective in the future," Dr. Flannigan said.
"And that doesn't even begin to address many parts of the globe where they have traditional fire-suppression approaches, which will be completely overwhelmed. So the risk to life and infrastructure is only going to increase under climate change."
Dr. Flannigan said when fires become too intense, they simply can't be stopped head on, and he noted we have already seen fires like that in the Alberta community of Slave Lake, where 7,000 people had to flee last year as the fire raced into the town, and the Okanagan fire that burned more than 200 homes in Kelowna in 2003.
Dr. Flannigan said the forest-fire season in Alberta starts earlier and lasts longer because of climate change, and that trend is expected to continue.
"The warmer it is the longer the fire season, the warmer it is the more lightning we have … and the warmer it is the drier our fuels are … the needles, the leaves the grass, and it will be easier for fires to start and spread," said Dr. Flannigan.
He said fire-smart programs – such as one in B.C. that promotes the clearing of forest-fire threats that surround communities – are one way to prepare for changing conditions.
But in the end, he said, people may just have to accept that there will be more forest-fire smoke in the air, as fire crews are forced to stand back and let the more intense fires burn themselves out.
That could lead to increased health problems.
Fay Johnston, a research fellow at the University of Tasmania, Hobart, Australia, said "landscape fires," which includes forest fires, grass fires and fires set to clear land, kill an estimated 340,000 people annually around the globe.
Dr. Johnston said a team of scientists from the United States, Canada and Australia came up with that figure recently.
"Our aim was to get a rough estimate, a ballpark figure. … Almost half of these deaths were in Africa … and the other part of the world which had a huge impact from fires was Southeast Asia, and it was roughly 100,000 in Southeast Asia, with the remainder more evenly distributed over the globe," she said.
Dr. Johnston said medical conditions linked to the inhalation of smoke is what causes most forest-fire-related deaths.
Mark Hume