NORTHWEST TERRITORIES
Some people point to climate change as one possible reason for this year's spate of forest fires in the NWT.

David Phillips, a senior climatologist with Environment Canada in Toronto, says the Mackenzie region of the NWT has seen the highest rise in annual average temperature in Canada. - photo courtesy of David Phillips, Environment Canada

However, David Phillips, arguably Canada's best-known climatologist, is not quite ready to assign blame to climate change.

"I think it's easy to sort of suggest that it may very well be climate change, but I think, when it comes right down to it, it's a bit difficult to prove in a scientific way," he said of the forest fires during a telephone interview with News/North last week.

"I think, for example, what you're going through now is because it's been so dry and warm in the last little while, and that will create a situation to bring on forest fires," said the senior climatologist with Environment Canada in Toronto.

Phillips said, in a sense, the NWT is not getting enough weather, which to a climatologist means storms.

"You're really having no weather, that's the problem," he said. "If you had some weather, this wouldn't be an issue."

Phillips noted western North America has been dominated for a long time by a ridge of high pressure.

"It's almost as if you're into a weather-free zone," he said. "It's almost as if weather is discouraged from coming into this area."

In recent years, there has been a "slowdown" of conditions, he said, noting some have related that to a "loopy and diving" jet stream.

Phillips said areas get the same weather, but it is changing in terms of duration, intensity and the area affected, and can even sometimes be out of season.

It means the possibility can't be ruled out that, by next summer, people in the NWT may be complaining because it won't stop raining, he said. "The new norm is to expect the unexpected. Expect these wild swings."

The climatologist also noted there have been "spitting" amounts of rainfall in the Mackenzie region this summer, such as 6.3 mm in Yellowknife between June 1 and July 15, when there would normally be 44 mm in that time period.

As for what all this means for forest fires in the future, Phillips said it may be a sign of things to come. "It's not a shock to think that what we're seeing this year may very well be almost the dress rehearsal, be almost the opening act, to what will be commonplace in the years to come."

As for the rest of this summer, Phillips said there is no improvement to be seen in the weather models, which predict warmer-than-normal temperatures for August and September.

"Relief doesn't seem in sight from our seasonal forecast and, in terms of the long-term picture, it's something that I think the people in the North are going to have to deal with," he said. "This is not just a one-off. This is not just the 100-year storm, so to speak."

Although the lack of rain may or may not not be attributable to climate change, Phillips has the numbers to show the Mackenzie region – the area draining into the Mackenzie River – has become hotter over the decades, and in fact has warmed up the most in Canada.

The world on average has warmed by about 0.9 of a degree Celsius in the last 100 years, he noted. "It doesn't seem like a lot, but that's unprecedented in terms of the speed of the change globally. Now, most of that has occurred in, say, the last 30 years, but that's the average over the 100 years."

However, Phillips said Canada has warmed up twice as much as the rest of the planet, and the Mackenzie region even more, and that is based on the past 67 years of reliable temperature readings for the whole country.

Canada's average annual temperature has warmed by 1.6 C, while the Mackenzie has warmed by 2.6 C.

"They are dramatic," Phillips said of the temperature rise in the NWT. "You guys are burning up. I can't emphasize enough that in my business a tenth of a degree, a half a degree, is a sea change."

There are variations by season in the Mackenzie region. The average winter temperature has increased by about 4.5 C over the 67 years, while the summer increase has been 1.7 C.

Phillips said the warming in the Mackenzie region is among the fastest on the planet with the only comparable area perhaps being northeastern Siberia.

As for why the Mackenzie region has seen such an increase in temperature, Phillips offers a number of possible explanations.

One is the area's continental climate, which warms up faster than a marine climate.

Plus, he noted the Mackenzie region's surface snow, ice and permafrost have taken a beating. "So when you lose that kind of reflective surface, well then the surface that you're left with absorbs the radiation and warms up, and so this increases temperatures."