If you’ve driven the Icefields Parkway between Jasper and Lake Louise, chances are you’ve stopped at the toe - or what used to be the toe - of the Athabasca Glacier. The Athabasca is one of several large valley glaciers that originates from the Columbia Icefield, which straddles the border of British Columbia and Alberta in the Canadian Rockies. The terminus of the Athabasca Glacier has retreated over 1500 metres since the 1900s, and glacier melt sends approximately 13 million cubic metres of water per year down the Upper Athabasca River. For context, that’s more water than the entire City of Prince George uses in a single year.
Satellite observations also tell us that the Athabasca Glacier has thinned, slowed down, and its exposed ice surface has darkened considerably in recent years. And as we see this story repeated across the globe, the United Nations recently declared 2025 as the International Year of Glacier Preservation, and March 21 as the World Day for Glaciers. The reason for the global demise of mountain glaciers is simple enough: small increases in temperature caused by human emissions of greenhouse gases. It’s been estimated that mean annual temperatures at the Athabasca Glacier increased by only 0.5°C between 1965 and 2018, but this is enough to increase rates of snow and ice melt in summer, decrease overall snow accumulations in winter, and increase the length of the melt season. As a result, the glacier surface accumulates greater concentrations of dust, pollution, and wildfire ash. The darker surface melts faster, and the now-exposed bedrock radiates heat back towards the glacier, which is locked into a feedback cycle of increasing glacier melt triggered by small changes in temperature.
Continued increases in global temperature (again, due to the burning of fossil fuels) will result in the loss of 70% of the glacier volume in the region by 2100, which will have major consequences for rivers and ecosystems and people living downstream. The Upper Athabasca River, sourced directly from snow and ice melt on the Athabasca Glacier, could see August streamflows decline by 60% by the end of this century. So this March 21st on World Glacier Day, think about the glaciers you’ve encountered in your travels, or in your rivers, and try to imagine a world without them, and what it might take to prevent that from happening.
UNBC students heading towards the toe of the Athabasca Glacier during the 2024 Physical Geography Field School (photo: J. Shea).