Remote Sensing of Environment, 7 January 2022
The compounding effects of climate change are particularly evident in Western Canada, where this detailed study of glaciers in Alberta and British Columbia found that ice loss was seven times faster between 2011-2020 than between 1984-2010. This extreme loss was even more pronounced for small and low-altitude glaciers in regions such as Vancouver Island, on the southwest coast of British Columbia, where glaciers melted 32 times faster. Vancouver Island glaciers are at a lower altitude than most coastal mountain regions. While they received increased levels of precipitation during this period, temperatures above freezing higher up these mountainsides due to global warming caused precipitation that previously might have fallen as snow, instead to come down as rain. This accelerated glacier melting further, and did not allow any substantial snow cover to accumulate over the top of the Island’s mountains. These factors together greatly accelerated glacier ice loss and retreat: there were 55 glaciers on Vancouver Island in 1984; today, only 38 remain. Glaciers represent a critical source of stored freshwater in western Canada; they allow local communities to generate hydroelectric power, and moderate extreme temperatures such as this past summer’s heat wave in the region. Authors emphasize that this glacier ice loss from western Canada is likely irreversible, and will continue accelerating unless global emissions are quickly and dramatically reduced.