Towns built on permafrost most at risk as temperatures rise in High Arctic

On Nunavut's Melville Island, where temperatures soared to more than 20 C this past July, a thick layer of cold, gooey topsoil sloughed off and flowed down a slope, much to the shock of a team of researchers camping nearby.

At the valley bottom, where the landslide finally stopped, a series of new ridges formed. Thick mounds of soil were deposited along 200 metres of a river channel, damming the river and changing its flow.

From one day from the next, the landscape was torn apart and transformed as once-frozen soil melted and slipped, like "a carpet down slopes," says Dr. Scott Lamoureux of Queen's University.

In Nunavut, permafrost melt could lead to huge problems for people, plants and animals, with additional damage on roads, pipelines and airstrips, he says.

Damage from melting permafrost will likely be less severe in places like Iqaluit or Rankin Inlet, which are largely built on bedrock, but Cambridge Bay and Kugluktuk are among the Nunavut communities that could suffer from this kind of disturbance.

In Cambridge Bay and Kugluktuk, elders have said for years that permafrost is melting, with vegetation growing in places where ice used to be common.

"Land is crumbling into the ocean. Whole riverbanks are crumbling into the river, also other embankments around the coast… the permafrost is melting in and around the community as well as along the whole coast," said Tommy Pigalak of Kugluktuk in 2003.

Natural Resources Canada recently funded an Adaptive Decision and Planning Tools (ADAPT) project to help Cambridge Bay, as well as Baker Lake and Pond Inlet, plan for climate change.

Permafrost melt may also have an impact on resource development on Melville Island. In the 1960s and 70s, gas was discovered on the island and, at that time, there were even plans to build a deepwater port and a pipeline to Ontario.

Warmer temperatures in the future could make it economically feasible to liquefy Melville Island's natural gas and ship it through the ice-free Northwest Passage or by other means.

Lamoureux says that permafrost research from Melville Island could assist decisions about how to develop gas and oil there. "Careful engineering" will be key to sound development practices because wells, docks, buildings and airstrips must be built to resist the impacts of permafrost melt.

Having studied Melville Island every summer for the past five years, Lamoureux's team of researchers now plan to return to investigate and document what happens there over the longer term.

Their camp is on the south-central coast of the island, not far from the border with the Northwest Territories. The nearest landmark is Winter Harbour, where the British explorer Sir William Pary once wintered over in the early 1800s and Joseph-Elzéar Bernier claimed the High Arctic islands for Canada in 1909.

If longer term warming occurs on Melville Island, sovereignty will be the least of the island's worries. If the thawed layer becomes even deeper, Lamoureux says, this will result in more movement and erosion.

In the Sahka republic of Siberia, melting permafrost has already turned solid land to mud in many villages, with disastrous results. More than 500 private and public buildings have buckled due to permafrost melt in the city of Yakutsk.

Lamoureux says permafrost melt can also have a huge impact on water quality. He and the other researchers watched the rivers affected by landslides change from clear to turbid and muddy.

"We just don't know what this means in terms of ecological impacts," he said.

These changes could affect fish or the breeding grounds of Melville Island of a small Arctic goose, the Gray Brant goose, already considered one of the smallest and more rare goose stocks in the world.

Another danger may also lie below the surface of Melville Island, where thawing soil could release greenhouse gases, including carbon dioxide and methane, into the atmosphere.

Researchers say this release of gas could have a serious effect on the climate and increase the rate of global warming, a phenomenon Lamoureux's team is also looking at.

Further to the north, Ward Hunt Lake, the most northerly lake in Canada, is also changing.

Ward Hunt Lake remained solid ice for thousands of years, but a melted moat of water now forms in the lake for about two months a year.

And studies show this ice melt, which probably started near the beginning of the industrial age 200 years ago, means tiny, green plants can thrive in the lake water.

Last summer, researchers with Laval university dove down below four metres of ice cover to retrieve sediment cores from the lake bottom.

Analysis confirmed the existence of aquatic life associated with warmer melt seasons in the top sections of the core.

The presence of this algae is "a warning flash" of climate change, said one of the authors of a paper called "Abrupt changes in extreme northern Canada," published in the Sept. 28 edition of the Geophysical Research Letters journal.

Previously, researchers have reported the break-off of a huge ice shelf from northern Ellesmere and the disappearance of 40 ponds at Ellesmere Island's Cape Herschel.

"These are the cold places in the Canadian Arctic and we are starting to see these impacts. That's the surprising part," Lamoureux says. "To see this in an extreme, cold climate suggests there will be no place on earth that's not vulnerable to change."