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John Pomeroy first visited Athabasca Glacier in Jasper National Park about 45 years ago, when it was located just 40 yards from the parking lot.

A University of Saskatchewan hydrologist who has conducted research on the glacier now describes it as a long walk to get to the ice.

“It has changed significantly over this period and continues to regress,” Pomeroy said. “Lake Sunwapta was formed after the 1950s as a result of ice retreating over a long period of time. It was the only lake below the glacier, and now three proglacial lakes have formed in the last decade.”

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The Athabasca Glacier itself melted more than 40 centimeters in one week in September and about five meters last year. In Banff National Park, Peyto Glacier has melted 4.7 meters this year by the end of August, down slightly from the 2023 6.5 meters it reached then.

Although warmer temperatures are the main culprit, smoke from wildfires darkens the surface of glaciers, which reduces the reflectance of sunlight, also called albedo.

Glaciers should reflect about 30 percent of solar radiation, but in recent years the Athabasca Glacier reflected only 15 percent.

“I don’t know if the fires that hit the town of Jasper affected the glacier,” Pomeroy said. “Prevailing winds tend to carry smoke eastward, so it tends to be upland fires in British Columbia that impact it more than localized fires in Jasper National Park.”

According to a 2022 study, darkening ice could increase the glacier’s melting rate by up to 10 percent after the smoke clears.

Scientists determined the incidence based on precise measurements during forest fires on the Athabasca Glacier that occurred over a six-year period. They also used satellites to measure ice reflectivity for the glacier and the entire Columbia Ice Field.

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“Ice melt does not increase while smoke is still in the sky, but once the smoke clears and ash settles on the glacier, the glacier remains dark for many months,” Pomeroy said. “And the algae grows on the ice, which holds all the soot particles in place in the ice crystals and can keep them there for years, so the meltwater from the fire actually melts a year after the fire.”

He added that bus tours offered on Athabasca Glacier were largely melt-free, noting that tire cleaning on those buses was effective and that the concentration of residual diesel exhaust was not sufficient to darken the ice.

Glaciers help with ‘drought protection’

Pomeroy estimated that the Athabasca Glacier would disappear by the end of the century, and the Peyto Glacier could disappear within a decade.

According to Pomeroy, glaciers help “drought-proof” mountain rivers during the hottest and driest weather. This benefits downstream communities, provides cold water for trout and salmon to thrive, and provides more consistent hydropower generation.

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But he estimated that by 2085, the Athabasca River’s flow in the town of Jasper would decline by 14 percent overall, with August flows dropping to one-fourth of current levels.

“So much of it comes from glacier melt,” he said. “If we look even to 2040 – so really not that far away, 15 years from now – we will see that flows will be down by 40 percent in August.”

He added that large glaciers like those in the Columbia Icefield modify the climate around them, and as they shrink, the region and other parts of Canada will experience more warming, which could lead to more wildfires.

Greenhouse gas emissions need to be reduced, says hydrologist

Pomeroy noted that the only way to protect glaciers is to protect the climate, which means reducing greenhouse gas emissions.

“We are putting the planet in a state that has not been seen since humanity evolved as a species, which is destroying our natural landscapes, our natural water resources and our natural life support systems, and making our communities uninhabitable in many places. , so there is a sense of urgency here,” he said.

“We need to get the situation under control very quickly. We may still not be able to save the Athabasca Glacier, but we can save the Columbia Ice Field, and maybe we will still be able to keep rivers flowing and everything else we need to sustain life.

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