A sudden shift in the wind at a critical time of day was all it took to send a wildfire out of control through Fort McMurray, forcing more than 80,000 people out of their homes in what has become the biggest natural disaster in Canadian history.
Earlier this week, Darby Allen, the regional fire chief for the area, minced no words when he was asked what might happen now that more than 1,600 homes have been destroyed.
''This is a really dirty fire,'' he said. ''There are certainly areas within the city which have not been burned, but this fire will look for them and it will take them.''
The media line now is that fire experts saw this coming five years ago when one of the Flattop Complex fires tore through the Alberta town of Slave Lake in 2011, forcing everyone to leave on a moment's notice. A report released shortly after predicted that something similar could happen again, and its authors made 21 recommendations to prepare for the possibility.
But fire scientists and fire managers actually saw this coming back in 2009 when 70 of them gathered in Victoria to address the issue of climate change and what impact it was going to have on the forest fire situation in Canada. Each one of them was already well aware that fires were burning bigger, hotter, faster, and in more unpredictable ways than ever before.
''We're exceeding thresholds all the time,'' said Mike Flannigan, who was at the time a research scientist with the Canadian Forest Service. ''We'd better start acting soon.''
''We let 150 wildfires burn each year and we need to be more transparent about that,'' said Judi Beck, Manager of Fire Management for BC Wildfire Management Branch. ''The public needs to know what we can and can't do.''
Gordon Miller, a director general with the Canadian Forest Service, summed it up succinctly, saying, ''More fires mean more communities will be at risk.''
'Strongest signal yet'
Flannigan is now a professor and research scientist at the University of Alberta. He remembers the meeting well because the participants were so bluntly honest about what they knew, what they didn't know, and what needed to be done.
''Many of us saw a Fort McMurray-like situation coming back then and even earlier, but frankly none of us expected anything as horrific as what has happened there this week. This is a signal, one of many, and the strongest we've seen yet, that suggests that the fire situation is going to get a lot worse, and that in some cases, there will not be much we can do about it other than evacuate communities.''
Flannigan declined to say whether enough has been done to prevent or better manage what has happened in Fort McMurray. ''Things are much too raw right now,'' he said, ''and we don't have all of the information and facts yet.''
But some Fort McMurray residents are beginning to question why it happened and why it took so long to tell people to get out. ''They evacuated us so late,'' resident Crystal Mercredi told CBC's The Current. ''So late that people were stuck in traffic and people were calling the radio station, saying... 'We're bumper-to-bumper. We can't move. Come and save us...we're sitting ducks.''' Another woman couldn't believe the elementary school that her child attended was evacuated just an hour before it burned down.
It's not that no one has been listening. This year, governments started preparing for the fire season a month earlier, as the Flattop report recommended. And efforts are underway to make many communities fire smart.
$9 billion catastrophe
But the fact is many decision-makers have been in denial or slow to move in addressing the fact that climate change is the new dragon in the forest, and that El Niño events like this year's make these dragons more volatile. The Alberta government this year reduced the fire prevention and management budget by $14.6 million.
Along with B.C. Premier Christy Clark, Saskatchewan Premier Brad Wall wants a national fire strategy but he refuses to accept the fact that something needs to be done to address climate change, which is the main reason why the area burned in Canada each year has doubled since the 1970s and why the number of fires is likely to double or even triple in the decades to come. Alberta Premier Rachel Notley is sincere about addressing climate change, but not at the expense of ramping up oil sands and fossil fuel production, which is driving climate change.
It's skewed logic when you look at the numbers the Bank of Montreal put out on Thursday. Its economists predict that insurance claims arising from the Fort McMurray fires could be as high as $9 billion. And that's just a small part of a bigger picture that's been emerging.
Since 2011, boreal forest fires in Canada, the United States and Russia have destroyed more trees than all that were burned in the rainforests of the world. Canada and the U.S. now rank second and fourth among countries with the greatest amount of annual tree loss. Russia, which is home to the world's biggest boreal forest, tops the list.
The growing cost of fighting wildfires is already overwhelming the ability of governments to manage their forests. For the first time, the government of Alberta couldn't fight all of the fires it wanted to fight in 2015 even though it brought in help from Mexico and Australia at one point to save some oil sands operations. And for the first time in Canada, wildfire management costs associated with the fires of 2015 topped the $1-billion mark.
Climate change: the big dry out
There are a number of reasons why fires are going to burn bigger, hotter, faster, and more often in the future. There are more people living and working in the boreal forest, and like it or not, people start a lot of fires -- more than half that occur in Canada. And in fighting fires so religiously to protect valuable timber, oil sands, pipelines and communities, we've created an unnaturally large amount of old growth forest in the boreal, where spruce and pine are prevalent and highly combustible.
But there isn't an expert out there who doubts that climate change is the biggest reason why we're losing the battle to control wildfires.
For every one degree of warming, there needs to be 15 per cent more precipitation to keep the fine combustible fuels on the ground sufficiently moist. So if temperatures rise by about three degrees by the end of the century, which is as conservative an estimate as there is, we'll need 45 per cent more rain. Flannigan says there is nothing in the climate models that suggest we'll come close. In fact, we're likely to get less precipitation in some areas.
More heat is also going to result in more lighting, which currently accounts for 85 per cent of the area burned in Canada. Typically, lightning occurs in clusters where there can be 50 to 100 strikes in a day. But increasingly we're seeing lightning events such as the one that occurred in Alaska last year when a slow-moving storm unleashed 50,000 lightning strikes in just five days. More than five million acres of trees were destroyed in a fire season that turned out to be second worst in the state's history. No one had ever seen anything like it.
What's more, insects like the mountain pine beetle and the spruce bark beetle that kill or weaken mature spruce and pine will continue to proliferate in these warmer environments, adding fuel for combustion.
One way to mitigate the problem is to let more fires burn. But in Alberta where there are so many oil sands, pipelines and fracking operations, that's almost impossible to do.
Letting fires burn in more remote places is also risky because there's the potential that it will get out of control. The only way to stop a fire like that is to light another one in front of it to starve it of fuel.
This can only be done when the winds are relatively calm and when there is a break in the topography that allows fire fighters to anchor in.
Will oil sands combust?
The chances of oil sands bitumen catching fire are remote because it is mixed with sand and very difficult to ignite. Most of it is buried in subterranean conditions where there is very little oxygen to feed a fire. What's more worrisome is the peat that lies beneath the boreal forest. If a forest fire is sufficiently hot enough, it can burn deep into the peat and smoulder through the winter, potentially destroying seedlings and re-igniting once the snow melts in spring.
Ted Schuur has spent the better part of his career making the connection between climate change and wildfires. If more fires begin to burn through layers of moss, leaves, and other organic materials that insulate permafrost from surface heat, says the Northern Arizona University scientist, they could release vast amounts of carbon as there is twice as much carbon trapped in permafrost as in the atmosphere.
''As more and more of this carbon is released from the permafrost, temperatures are going to rise even faster,'' he says. ''Permafrost carbon may not be as visible as changes in sea ice, but you can bet that big changes are happening there and it's going to have a big impact on the future.''
Some experts are now talking about the possibility of a 3.5-million-hectare fire that will exceed anything we have seen in North America in the past 150 years.
Chinchaga as recurring nightmare
No one knows what such a fire would look like, but the Chinchaga Firestorm of 1950 gives us an idea. It burned for 222 days and torched a stretch of forest that was 280 kilometres long.
It had been an exceptionally hot spring, just as it has been in western Canada this year, when a small wildfire ignited in northern British Columbia. Firefighters were too busy battling other fires to do anything about a little fire like this, which was remote and relatively far from human settlement.
Within a few days though, it crossed into the wildlands of Alberta where the tinder dry forest went on forever. A giant pall of smoke from the blaze led some people in the south to believe that an atomic bomb had exploded.
It was not an alien invasion, a volcanic eruption or an eclipse of the sun as others suspected. At one point though, flights in Canada and the U.S. had to be cancelled. In Buffalo, Pittsburgh, Cleveland, Fort Erie and many towns in New York, it was so dark at mid-day that lights in baseball fields, including those at Yankee Stadium, had to be turned on. Smoke from the fire travelled all the way to Europe. Some Danish people were so jittery when they woke up to see a blue sun rising over the horizon that they went to the bank to withdraw their life savings.
It wasn't just people who were affected. One farmer in Jamestown, New York, described how his chickens, which had fanned out for their midday foraging, "suddenly realized they were being caught by darkness, so they scurried back across the cow yard in more than usual earnest, their heads moving in delayed jerks.''
Astronomer Carl Sagan was so intrigued by the Chinchaga fire that he looked into the event to see how it might fit into his concept of a ''nuclear winter.''
According to Flannigan and fire expert Cordy Tymstra, who recently wrote a book on the fire, Chinchaga changed the way we fight fires. But they also say that the time has come to rethink much of what we have learned since then because there will be many more fires, and more assets -- small towns, oil fields, pipelines, mines, lodges, and endangered species -- that will be in the line of fire.
"I liken Slave Lake and Fort McMurray to a bloody nose," says Flannigan. "Sometimes we need to suffer several bloody noses before we change our behaviour."
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