Home Glaciers Extreme summer heat wave hit West Kootenay ice fields hard – BC News

Extreme summer heat wave hit West Kootenay ice fields hard – BC News


John Boivin, reporter with the Local Journalism Initiative, Valley Voice – | History: 346822

Scientists studying the West Kootenay glaciers say local ice fields have lost millions of tonnes of mass this summer, heightening fears about their long-term survival.

“It’s scary, but it’s not unexpected,” said Dr. Brian Menounos, internationally renowned glaciologist at the University of Northern BC. “Climatologists have been talking about it for several decades. “

“This is not good news for glaciers.”

Climatologists say the relationship is clear: The end result of adding thermal energy to the atmosphere is the melting of snow and ice.

Menounos uses historical and real-time satellite images to map changes in the surface elevation of glaciers around the Earth. He says the preliminary analysis of the aerial overflights this summer shows a huge loss for the Kokanee Glacier. The surface of the ice field has sunk approximately 2.7 meters from 2020 levels.

“This year for this particular glacier has been particularly bad,” he says. “These measurements show that over the past year, the Kokanee Glacier has lost about two meters of water equivalent. It is a very strong year of mass loss.

Kokanee Glacier is at the center of the 320 square kilometer Kokanee Glacier Park and feeds over 30 lakes and countless streams that feed Kootenay Lake and the Columbia River system.

A combination of factors led to the massive loss of ice. The drought that lasted for months in the region reduced snow levels. This thinner snowpack was then lifted off the top of the glaciers by the extreme “heat dome” in July, leaving the main glacier ice exposed for the remainder of the summer.

Melting was occurring even atop the highest peaks in British Columbia, Menounos explains.

“It quickly melted that blanket of snow and exposed the ice to a much longer melt season,” he says. The soot from forest fires covering the ice fields also contributed to the melting. “On top of that, you’re changing the degree of reflection of those surfaces by the massive wildfires we’ve had this summer in British Columbia.”

Denver’s new glacier: gone by 2030?

The Valley Voice asked Menounos to check the condition of the New Denver Glacier – a small ice field in Valhalla Provincial Park – to see if he could determine the effects of summer. The results were worrying.

“Really, over the last decade or so, we’ve seen a fivefold increase in the rate of thinning on this particular glacier,” he says. “He went from a neutral equilibrium – gaining as much as he lost each year – to losing an average of half a meter of water each year.

“I don’t expect this to stop.”

If this glacier continues to lose ice – and because of climate change, this is the most likely scenario – it could disappear as early as 2030, he says.

“Probably in my lifetime, certainly in my children’s lifetimes, this glacier will cease to exist,” he says. “And it will be one of the glaciers that I wouldn’t be surprised to lose by the end of this decade.”

The loss of the New Denver Glacier will not mean the end of the watershed, Menounos says. Annual snowfall is expected to keep the water system flowing.

“The disappearance of the New Denver Glacier… will not necessarily affect the area of ​​runoff defined by seasonal snow or non-solid precipitation,” he says. “But now is the time, the heat stress that will occur if we lose our snow and ice. We are simply subjecting aquatic ecosystems to substantial stress, and they are already feeling the stress of a number of factors. “

The ice field is like a reservoir of cold, and without it, the ecosystem loses an important balance.

“They are Mother Nature’s natural reservoir, perfectly suited to release water when needed,” he says. “Unfortunately, our actions – greenhouse gas emissions from the use of fossil fuels – cause these reservoirs to release water far too soon and we are depleting these reservoirs.

“If you remove this thermal buffer capacity from glaciers, you end up in a situation where these aquatic ecosystems are going to change,” Menounos said.

The fate of the New Denver and Kokanee glaciers is no different than that of the more than 16,000 glaciers and glacierettes in British Columbia, and the hundreds of thousands of people around the world that Menounos’ team studied. Their work, published in the journal Nature this spring, found that the rate of thawing of the world’s ice fields quadrupled between 2000 and 2019.

“We’re at the point where greenhouse gas emissions continue to operate as usual, we won’t see a simple linear increase, but we expect the temperature rise to accelerate,” he says. “By 2040-2050, you start to see a dramatic increase in temperatures.”

Glaciers are a crucial source of fresh water, here and around the world. More than a billion people could face water shortages due to the loss of glaciers, the Nature study suggests.

“It is essential to quickly reduce greenhouse gas emissions. It must be done now, ”says Menounos. “If you cut the CO2 tomorrow, there is still a lag in removing this excess carbon dioxide from the atmosphere. Stop it now and you will still see an increase.

We must all do our part if we are to change a bleak future, he says.

“One of the strengths people need to understand is that we all play a part in the solutions, and it’s not necessarily about looking at things like recycling – which is important – but we have to look at our fashions. life and see what other sacrifices we are willing to make. do, ”he says. “Some of the actions we are taking here will affect less fortunate nations and people need to understand that.”