Tuesday, 18 April 2017 16:36

'It scares me': Permafrost thaw in Canadian Arctic sign of global trend

Canada is melting.

Like a popsicle taken out of the freezer and left on the counter, the permanently frozen ground in the northern reaches of this country is thawing at an ever-faster rate.

Half of Canada is blanketed in some form of permafrost, including patches in the northern reaches of Ontario and the Prairie provinces.

But in many places, including around Inuvik, NWT, as much as 90 per cent of this "ground" is actually frozen water. (The rest is dirt, rocks and decomposed organic material that was once trees, shrubs, even animals.)

For years now, buildings in Inuvik have been gradually sinking into the ground as it softens. Others are so unstable, they are literally sliding off their foundations.

"You can really see the effect of the permafrost," said Inuvik mayor Jim McDonald, standing in front of two warehouses built in the 1980s that are now unsafe to enter and are slated for demolition.

"The seasonal thaw is getting deeper now, and that wreaks havoc."

This is where a local problem becomes a global concern.

Scientists in the Northwest Territories, Alaska and Siberia are now realizing that as the ground under them melts, it will not only make life harder for the people living in the Arctic, but will in fact speed up climate change around the globe.

Temperature swings

The World Meteorological Organisation says the globe is now in uncharted territory, with temperatures in 2016 the hottest ever recorded.

Effects of climate change can be difficult to spot for most Canadians, but not in Inuvik.

Jim McDonald has lived here his whole life — his father helped build the town when it was created from scratch in the 1950s.

He said that in the Mackenzie River Delta, the cold used to set in by October and stay that way into May. Temperatures would regularly dip to -40 and remain there for weeks at a time.

But McDonald said that in recent years, winters are much warmer and much shorter. It's also more unpredictable. Wild temperature swings are common.

The thaw is destroying buildings, forcing construction crews to change their methods. Buildings used to be hoisted on stilts sunk five or six metres into the ground. Nowadays, said McDonald, "they're finding that they have to go down in the 15- or 20-metre range to get a stable enough foundation."

In melting the permafrost, the changing climate is not only unsettling buildings but making transportation in the region more difficult.

For decades, the community of Tuktoyaktuk, on the shore of the Arctic Ocean, has relied on an ice road from Inuvik in winter. But because of warmer temperatures, the road's season is shorter and faces periodic closures as the ice shifts and becomes unstable.

This spring it will close for good, to be replaced by a permanent gravel road that will be known as the Inuvik-Tuktoyaktuk Highway.

'It scares me'

Above the Arctic Circle, the permafrost hasn't melted since at least the last Ice Age, more than 10,000 years ago. 

No one knows exactly what it will unleash when it melts. But no one thinks it will be good.

At the very least, it's changing the landscape. The Mackenzie Delta is a maze of small lakes and broad hillsides. People who live in Inuvik say they don't have to travel far from town in the summer to see craters that formed when the surface layer of land simply collapsed. 

They also see entire hillsides that have slid away, and have found entire lakes that have drained — as well as others that have been newly formed.

When permafrost thaws, all the organic material previously trapped in it releases methane into the atmosphere.

"It scares me," said Kumari Karunaratne, a permafrost expert who works for the Northwest Territories Geological Survey. "This methane that's being released is being released over huge areas across the north. And it's continually seeping out."

Methane is a greenhouse gas that is 25 times more potent than carbon dioxide. So, as climate change speeds up the permafrost melt, the permafrost melt will exacerbate climate change.

By exactly how much, it's impossible to say. Karunaratne won't even try to guess, because measuring it is difficult and imprecise. The area where it's happening is vast and much of it remains uninhabited and unexplored.

But there are dramatic examples that show just how much methane is bubbling up from underground. Some lakes in the Arctic are so full of it, if you punch a hole in the ice you can light the escaping gas on fire.

YouTube has videos of researchers and others doing it in Alaska and Siberia. But the same thing is happening in the Northwest Territories.

Unleashing other problems

There are other problems, too.

Last summer in Siberia, the unusually intense summer heat melted the permafrost, exposing a reindeer carcass that had been embedded in it. 

That carcass was infected with anthrax, a deadly bacteria that had been locked in the ice. A 12-year-old boy died after being infected and at least eight others were sickened.

It opens up the possibility that other dangers could be unleashed.

Siberian researchers say a gravesite in one town contains bodies of people who died of smallpox in the 1890s. They were buried in the soil just above the permafrost, which is now melting. That's raising fears that smallpox, which was eradicated globally in 1977, could make a comeback.

Sergey Netesov, chief of the virology laboratory at Novosibirsk State University, told the Siberian Times newspaper that there are thousands of graves in the region — some human, some cattle. 

The recent anthrax outbreak, he said, is "reason enough to finance research into the diagnostics and prevention of exceptionally dangerous infections."

Whether that happens or not, people in the Northwest Territories know they have no power to stop climate change. 

Global temperatures are already at record levels and the polar regions are feeling the effects more dramatically than anywhere else.

"There are really remarkable changes that are happening in a short amount of time," said Karunaratne.

Link: http://www.cbc.ca/news/canada/north/it-scares-me-permafrost-thaw-in-canadian-arctic-sign-of-global-trend-1.4069173