'Not a good situation': B.C. heat wave concerning for glacier scientist

Vancouver -

B.C.'s recent heat wave has caused more concern about the future of the province's roughly 17,000 glaciers.

At the height of the "heat dome" that hovered over the province in late June, dozens of temperature records were broken, including some that had stood for more than 100 years.

The abnormally high temperatures were present at higher elevations, as well, and that's concerning to scientists like Brian Menounos.

Menounos is Canada research chair in glacier change at the University of Northern British Columbia, and he says the timing of the heat dome is what made it particularly damaging to the province's glaciers.

"Later in the summer we do get the occasional warm period, but this early in the season, it's not a good situation simply because we can rapidly reduce and thin the seasonal snow that's protecting the underlying ice lower down on the glaciers," Menounos said.

Even at elevations as high as 3,000 metres, researchers are seeing snow start to saturate with water and pools begin to form on glaciers.

This is concerning in two ways, according to Menounos. First, the loss of the seasonal snow that was sitting on top of the glaciers will leave the ice beneath it exposed to the sun for a longer period of time this summer.

Second, as the glaciers melt, their colour changes and they reflect less energy than fresh snow does. That change can serve to speed up the melting process, Menounos said.

"At the end of the heat dome, we had strong convection, which led to wildfires," he added. "The wildfires can also introduce a complicating effect. That is, they start to, in some cases, introduce soot, which is optically dark and allows more energy (to be absorbed) high up in the glaciers as well."

Glaciers are an important part of the hydrology of Western Canada, Menounos said, noting that they typically supply lakes and rivers in the late summer after the snow from the previous winter has melted.

He described them as a "buffer" against negative effects fish and other wildlife might experience during dry summers.

They're also one of the parts of the natural world that is most obviously susceptible to climate change, Menounos said.

He said research has shown that - under a "moderate emissions" scenario - B.C. should expect to lose roughly 70 per cent of the total volume of its glaciers by the end of the century.

"It is a concern," he said. "I don't think we as a society need any more indications that we have perturbed Earth's climate system."