|July 18, 2018|
Hundreds of Arctic glaciers shrinking, disappearing into 'city of icebergs,' study says
|The statistics in her recently published paper say it all: hundreds of glaciers in Canada's High Arctic are shrinking and many are likely to disappear completely.|
But for Adrienne White, seven field seasons along the northern reaches of Ellesmere Island give the numbers real-world immediacy.
"I've been actually able to see with my own eyes, to the point where there were some areas I couldn't recognize between years," said White, a University of Ottawa glaciologist.
"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."
White has catalogued and studied the condition of more than 1,700 glaciers on the High Arctic island, both on the ground and from satellite imagery. She looked at glaciers on land and flowing into the ocean as well as at ice shelves floating on top of the sea.
Out of 1,773 glaciers, 1,353 shrank significantly between 2000 and 2016. All of them shrank a little bit, said White.
"What I saw when I was measuring was 100 per cent of glaciers retreating," she said. "They all retreated. Nothing is growing."
White found glaciers lost more than 1,700 square kilometres. That's a loss of almost six per cent over a period of 16 years.
Most of these glaciers probably aren't coming back.
Glaciers not accumulating snow
The Canadian Arctic is experiencing some of the fastest climate warming anywhere on Earth. The annual average temperature on Ellesmere Island has increased by 3.6 degrees.
Data from other points in the Arctic suggest rising temperatures mean the elevation needed for snow to last through the summer has risen by 300 metres.
White found most of Ellesmere's glaciers are no longer high enough to accumulate snow.
"I don't see snow surviving throughout the summer," she said. "You need that year-long snow to be able to accumulate and create more ice and I just don't see that.
"Over 50 per cent of the glaciers are completely in the ablation zone, [where] 100 per cent of the glacier area is undergoing melt. No part of that glacier is creating more ice."
White's work echoes earlier research that found Ellesmere's glaciers began shrinking several decades before her study began.
Although she's not able to say whether that retreat is speeding up, the rate of warming is increasing.
Until the mid-1990s, the average temperature climbed about 0.12 degrees per decade. From 1995 to 2016, the increase was 0.78 degrees per decade.
It's hard to say what the consequences of shrinking glaciers will be, said White. There will be some impact on sea-level rise and the melting ice is likely to release more and larger icebergs into the water, she said.
Little is known about the area, which is so remote that until recently it couldn't even be found on Google Earth. One thing is certain, though, said White.
"It is a big change."