Heat wave in western Canada accelerates glacier melt, experts say

VANCOUVER – A scorching heat wave in the last week of June in western Canada has left little mark, including fragile glaciers that are already melting at an accelerated rate, experts say.

VANCOUVER – A scorching heat wave in the last week of June in western Canada has left little mark, including fragile glaciers that are already melting at an accelerated rate, experts say.

Dozens of temperature records were shattered during the period, including a Canadian record of 49.6 ° C in Lytton, British Columbia, the day before a fire destroyed most of the community.

Brian Menounos, Canada Research Chair in Glacial Change at the University of Northern British Columbia, said that even at elevations of 3,000 meters it was about six degrees above the average.

“Hotter than anything we’ve seen so it was clearly a warm, warm enough event.”

He and other scientists are working to quantify the melting of glaciers caused by the heat wave, Menounos said.

Most of the glaciers in the mountains of Alberta and British Columbia “were not in good condition” and are expected to disappear by the turn of the century due to greenhouse gas emissions and climate change caused. by human activity, he said.

Jeffrey Kavanaugh, associate professor in the Faculty of Science at the University of Alberta, estimated that the ice melt during the so-called June thermal dome on the Wapta Icefield was three times greater than normal during of the past twelve years. The Wapta Icefield is the source of the Glacier and the Bow River.

He looked at the data from June 25 to July 4 and compared it to temperatures for the same interval over the previous 12 years.

The temperature only dropped below zero once during this period; all other nights it stayed as high as 7.5 C.

“Because the increase in melt during the thermal dome event melted the snowpack in many places and exposed the glacier ice, it changed the rate of melt for the remainder of the summer,” Kavanaugh said.

“So the melt will be increased compared to a normal summer. Even though temperatures are normal, we will see even more melt the rest of the summer than we would otherwise have. This is an impact that will continue through the summer. less until the snow falls and covers the glaciers again. ”

Menounos said the heat coincides with the summer solstice, when the northern hemisphere receives “maximum energy” from the sun.

“It was really kind of a one-two punch.”

Smoke from the hundreds of fires burning across the province is an additional issue, with soot increasing melting and a blanket of smoke that reduces sunlight but also traps heat to increase glacier thaw, a- he declared.

“It’s a complicated research topic that a lot of people are starting to study and trying to understand better,” Menounos added.

This rate of glacier melt is typically seen in late July and August, he said.

Glaciers will experience a “longer melt season” if temperatures stay above normal, he noted.

“Glaciologists worry every time you get conditions that are going to keep melting for, you know, substantial amounts of time.”

This report by The Canadian Press was first published on July 14, 2021.

Hina Alam, The Canadian Press


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