Study raises concerns over rate of deglaciation in Western Canada

Researchers at UBC have predicted that the volume of glaciers in Western Canada will shrink by an alarming 70 per cent by the year 2100.

The study, which focused on Alberta and British Columbia, involved collaboration between UBC, the University of Iceland, the University of Victoria and UNBC. The research showed that the volume of glaciers in Western Canada will decrease by 70 per cent over the next 85 years.

Some regions were predicted to experience greater changes than others. The interior and parts of The Rockies will see losses greater than 90 per cent, while the coast is expected to experience relatively less volume loss.

By combining high-resolution, three-dimensional, physics-based models with previously used simulations, the researchers predicted the rate of change in both thickness and area covered by glaciers. Temperature change predictions from multiple studies were included in the model.

“We were really concerned about being able to present this information clearly so that people would wish to act on [it]” said Garry Clarke, the study's lead author and professor emeritus of glaciology at UBC. “People can see the glaciers and recognize them, and recognize that they’re changing, it’s the same message [as before] but in a much more powerful form.”

The analyses were conducted for four emissions scenarios published by the Intergovernmental Panel on Climate Change. These scenarios approximate the effect of different levels of air pollutant emissions on our atmosphere and represent a range of possible governmental climate policies. Generally, the four scenarios are: the effects of emissions decreases by 2100, the effects stabilize by 2100, the effects approach a peak by 2100 and the effects continue to rise through 2100.

Predicted change in glacial volume was dependent on the emissions scenario. Up to about 2050, the glaciers in Western Canada will decrease in volume regardless of emissions. However, the extent to which the glaciers melt in the latter half of the century will depend on how much we are able to curb our production of air pollutants and greenhouse gases.

Currently our emissions match those of the highest impact scenario. “The influence of [this scenario] is so large that glaciers will be the least of our worries at that point, the planet will be unrecognizable,” said Clarke. “The most important thing to do is to get off the high [emissions] path and the sooner you do it, the better things are.”

The broad impact of deglaciation ranges from negative effects on ecosystems, agriculture, forestry, alpine tourism, sea levels and water quality. The flow of meltwater into our rivers in the late summer is important for maintaining reservoir levels, controlling water temperatures and preserving aquatic species.

Decreased glacier runoff will also limit hydroelectric producing power which will have major economic impacts. Peak ice volume loss is predicted to occur between 2020 and 2040.

“We are quite keen to see this kind of work done in other parts of the world,” said Clarke when asked about future of this type of glacial modelling. “We know that the serious places for glacier loss on human populations would be Central Asia and South America because they do have quite a high dependency on melt from glaciers to survive.”