No respite for Canadian glaciers

(Vancouver) Atop a mountain overlooking Metro Vancouver, hidden at the bottom of a north-facing ravine, the region’s last glacier is melting at full speed.


The Coquitlam Glacier has survived in its hiding place for 4,000 or 5,000 years on the east side of the Coquitlam watershed.

Researchers warn, however, that it is one of thousands of glaciers that are melting faster than expected across Canada due to climate change, which could have implications for ecosystems, climate regulation, water supply water and tourism.

“It’s hanging on, but right now it’s disappearing very quickly, that’s for sure,” said hydrologist Peter Marshall of the Metro Vancouver water utility.

Mr. Marshall and his team are monitoring the glacier with lights and lasers, and their results are disturbing.

Between 2015 and 2018, the glacier lost about 50 centimeters per year. But since then, the pace has picked up to 2.25 meters per year. If the disappearance of the glacier is anticipated, this fivefold increase is astonishing, especially since it coincides with years of heavy snowfall, Marshall said.

“With above average snow cover, we thought it might slow down (the melting) a little bit, but I think the long, hot, dry summers that we have had for the past five or seven years have really accelerated the change” , he explained.

In 20 or 30 years, “we will officially say that there are no more glaciers in our region,” Marshall said, before warning that it could happen even sooner.

The Coquitlam Glacier is one of many glaciers in western Canada being monitored by researchers as warming temperatures and soot from wildfires contribute to melting.

Mark Ednie, a glaciologist with Natural Resources Canada, explains that Canadian glaciers play a special role in regulating the global climate, since the country has more square kilometers of glaciers than any other region of the globe except Antarctica and Greenland.

And those of British Columbia, Yukon and Alberta stand out for the speed of their melting.

“The melting of glaciers in western Canada and the northern United States is one of the fastest in the world, so that’s very, very telling,” Ednie said.

Western Canadian glaciers are a crucial source of water, feeding waterways like the Bow and North Saskatchewan rivers. With melting glaciers, water levels and quality will decline, which could potentially have a big impact on people in these areas, he added.

Mr. Ednie likens glaciers to reservoirs or banks of water. Right now we’re removing water that was stored in the 1800s, he said. “But at some point very soon,” he said, the melting of glaciers will peak, and then the flow to streams and rivers will decrease.

“We have to be prepared for that,” Mr. Ednie warned, noting that the impacts will be felt from hydroelectricity to agriculture. Understanding what is happening and preparing for the future is my central message. »

Mr. Ednie is one of three members of the National Glaciology Project, which is run by the federal government. He and his colleagues travel by helicopter and on skis to visit and measure the same ten glaciers at least twice a year.

Like the Coquitlam Glacier, it has seen alarming results. In Alberta, in Banff National Park, the Peyto Glacier retreated nearly 200 horizontal meters in 2021 after losing just 500 meters in the previous ten years, he revealed.

“We’re really coming to the end point of the disintegration of this glacier,” Ednie said.

Brian Menounos, the holder of the Canada Research Chair in Glacier Evolution, says he fell in love with glaciers during his youth, while hiking in the Austrian Alps.

“It was spectacularly beautiful. The ice cream in particular. I always tell my students it’s the most precious mineral on earth,” said Menounos, who teaches at the University of Northern British Columbia.

The role of glaciers in supplying rivers and streams with water after the snow has melted is crucial. Their disappearance would have dramatic consequences for salmon and other species, indigenous cultures, the economy and tourism, he added.

And while glaciers in western Canada don’t contribute much to sea level rise, neither do the ice caps and ice fields in the eastern Canadian Arctic. , which has global implications.

“This should be another unmistakable wake-up call that needs to be acted on now and decarbonized quickly,” Menounos said.

But the threats continue to multiply, he stressed. Last year was the so-called ‘heat dome’, which was followed by wildfires that deposited black soot on the white surface of the glaciers, causing them to absorb more heat. .

This year, the snowfalls were abundant, but the summer and the hot season stretched until October.

“It is a particular meteorological event. But if you put all these annual anomalies end to end, it gives a much more accelerated melt than what we usually see, he said. If I had to sum it all up, I would say there is no respite for glaciers. »

And despite everything we know about the vulnerability of glaciers, there are still many that we don’t know.

For example, only recently has it been accepted that forest fires and their role in reflecting light contribute significantly to melting, he said.

Mr. Menounos added that there is an urgent need to invest in research to obtain the data that will help us understand the impacts and develop better responses.

“We need to improve our ability to effectively monitor glaciers in British Columbia, Alberta and elsewhere,” he said.


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