Arctic torn to pieces as heat triggers landslides

Queen's University researchers watched in awe and dismay this summer as landslides blamed on climate change mangled wide swaths of a remote Arctic valley in mere hours.

"When a week was up the landscape had been torn to pieces in dozens of places. We were surprised by both the speed and the scale of the changes," said geography professor Scott Lamoureux.

He warned that such large-scale environmental upheaval could throw fragile Arctic ecosystems off-kilter by interfering with the flow of vital organic material and nutrients carried by water during the brief summer months.

"We expected this would happen in the future to some extent but to see it taking place already is a bit of a shock," Lamoureux said.

Lamoureux leads a Queen's University research team probing the impact of climate change on water quality in a 20-square-kilometre region at the southern end of Melville Island in the western Arctic.

The study began in 2003 and this spring expanded to include scientists from the University of Toronto.

The findings sound a warning for other areas of the Arctic, some warmer than the Melville Island locale.

Federal government surveys have concluded permafrost lies beneath about half the land mass of Canada, extending as much as 700 metres deep in the Arctic archipelago.

Lamoureux said the landslides were triggered in the last week of July after unprecedented high summer temperatures caused the permafrost on Melville to melt down as far as a metre, 20 times deeper than normal.

This excess water acted like a layer of ball bearings, letting the soil on top slide down the valley slopes.

"It was like a rug coming down and then piling up in the river channel in folds.

"Along one 200-metre stretch, it shifted the entire river bed to the other side," Lamoureux said.

Records going back to the 1950s show daytime highs averaging about 5C in July, but this past summer, temperatures regularly reached 15C and sometimes 20C, Lamoureux said.

"There were dozens of these slow-motion landslides. You couldn't see them move over a period of minutes, but they covered 50 or 60 metres in a day.

"One flowed down a good two kilometres from a ridge to the valley floor," he said.

The ecological upheaval most probably continued after the Queen's researchers left on Aug. 1, Lamoureux said, but he has been unsuccessful in obtaining satellite images to check on the final extent of the damage.

The geography professor said having before and after measurements of water flow and quality from the site is "scientific serendipity."

"From an experimental standpoint, we couldn't ask for a better situation," he said.

Also excited by the development is U of T professor Myrna Simpson, a specialist in environmental chemistry who joined the Melville Island project this year when the federal government provided nearly $700,000 as part of International Polar Year funding.

In her lab on the university's Scarborough campus, Simpson analyzes how carbon-based organic material ages differently in the Arctic compared to temperate zones.

"We're learning a lot of really new things," she said.