Ruminations

Blog dedicated primarily to randomly selected news items; comments reflecting personal perceptions

Wednesday, July 18, 2018

Canada's Diminishing Glaciers

"I've actually been able to see with my own eyes, to the point where there were some areas I couldn't recognize between years."
"One year you're Ski-Dooing over the ridges of these ice shelves, and then you go back the year after and [it's] like a city of icebergs."
"What I saw when I was measuring was 100 percent of glaciers retreating. They all retreated. Nothing is growing."
"I don't see snow surviving throughout the summer. You need that year-long snow to be able to accumulate and create more ice and I just don't see that."
"Over 50 percent of the glaciers are completely in the ablation zone, [where] 100 percent of the glacier area is undergoing melt. No part of that glacier is creating more ice."
"It is a big change."
Adrienne White, glaciologist, University of Ottawa
An iceberg floating in the Baffin Bay above the Arctic Circle dwarfs the Canadian Coast Guard icebreaker Louis S. St-Laurent on July 10, 2008. (Jonathan Hayward/CP)

Until the mid-1990s average temperature in the Arctic climbed about 0.12 degrees for each decade that passed, so what researcher-glaciologist Adrienne White discovered throughout her seven years of intensive study of the shrinking of glaciers in the Canadian High Arctic is not a recent phenomenon, although the rate of shrinkage has accelerated. From 1995 to 2016 glacier shrinkage had sped up to an increase of 0.78 degrees per decade.

Ms. White's work is similar to the kind of research undertaken in an earlier era discovering that Ellesmere Island's glaciers were in shrink mode; her work builds on that of the studies of decades before she began her own observations. According to the results she has observed the rate of warming is on the increase, but it had not yet been known whether the retreat of the ice has also been speeding up. Her work has taken place along the northern reaches of Ellesmere Island.

She has been busy through seven field seasons in cataloguing and studying over 1,700 glaciers on the High Arctic island to take note of their condition, assembling data derived both from her on-the-ground observations and from satellite imagery, each supporting the other in her final conclusions.
Of the 1,773 glaciers under her observation, 1,353 gave notice of significant shrinkage between 2000 and 2016; all were seen to have been diminished in size.
Ms. White examined the condition of glaciers on land, and as they flowed into the ocean, at ice shelves floating atop the sea and their shrinking presence validates her conclusions. This has been happening throughout the Arctic region, as well as at the South Pole, with Antarctica's immense ice cap and glaciers also losing significant mass. The Canadian Arctic is known to be experiencing some of the swiftest climate warming occurring anywhere on the planet. Ellesmere Island's annual average temperature has seen an increase of 3.6 degrees.

Through Ms. White's research, glaciers were found to have lost over 1,700 square kilometres, a loss of close to six percent over a sixteen year time frame, and what is being lost is likely to be a permanent loss; most glaciers, the experts feel, will never recover their former size. Moreover, according to data acquired from other areas in the Arctic, rising temperatures indicate that elevation required for snow to remain through the summer has also risen by 300 metres.

Most of Elesmere's glaciers are no longer in a sufficiently high range to enable them to accumulate snow, and without that accumulation due to higher temperatures prevailing, their capacity to grow has been critically hampered.
Ice floats in Slidre Fjord outside the Eureka weather station on Ellesmere Island, Nunavut, on July 24, 2006. New research finds that hundreds of glaciers in Canada's High Arctic are shrinking and that many are likely fated to disappear. (Jeff McIntosh/CP)

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