A fifth of Canada’s glaciers could be gone by the end of the century, a casualty of global warming that would drive a 3.5cm rise in sea levels, a study found on Thursday.
“Even if we only assume moderate global warming, it is still highly likely that the ice is going to melt at an alarming rate,” said lead author Jan Lenaerts, a meteorologist at Utrecht University in the Netherlands.
And “the chances of it growing back are very slim,” he said.
He said the process was both irreversible and self-reinforcing — because the snow and ice in the tundra and in the waters of northern Canada currently help reflect away some of the sun’s heat.
As they disappear, a larger portion of the suns rays will be absorbed by the water and land, which will cause temperatures to soar.
If Canada’s glaciers shrink by 20 percent, as under this scenario, that would correspond to an average global temperature rise of 3°C.
However, the temperature jump in the glacial regions of northern Canada would be far higher: 8°C, according to estimates by Lenaerts, who emphasized that this is not even a worst-case scenario.
The scientists urged policymakers to consider the prospect, saying that since 2000, the temperature in Canada’s Arctic Archipelago has risen by 1°C to 2°C, and the volume of ice has significantly diminished.
Over the least 20 years, sea level has risen on average by more than 5.3cm. Most of that increase has been attributed to the thermal expansion of water, with just a fifth coming from the melting of the polar ice caps, according to an international study published in November last year in the US journal Science.