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Home / Science / The recent decline in glacial losses in the Arctic is twice as high as in the previous 60 years

The recent decline in glacial losses in the Arctic is twice as high as in the previous 60 years



On the Hall Island, Franz Josef Land, a Landsat 7 image, from July 1
7, 2002 shows a strong ice cover on land and in the surrounding sea. The Landsat 8 image, mid-September 23, 2013 reveals far less ice cover, while the Landsat 8 image right on September 12, 2016 shows significantly lower glacier coverage. Credit: Cornell University

Geophysicists studying glacier changes in the Russian Arctic have found that the speed of ice mass loss has almost doubled over the last ten years compared to the records of the past 60 years, according to a study published on April 24 in Remote Sensing Surroundings.

The scientists focused on Franz Josef Land, a glaciated Russian island group in the Kara and Barents Seas – among the northernmost and most remote plots of land on earth. They examined the archipelago with high-resolution optical satellite imagery provided by the National Geospatial Intelligence Agency to study glacier dynamics.

"The glaciers there are increasing in area and height as the recent rate of ice loss increases, compared to the long-term ice loss rate," said lead researcher Whyjay Zheng, Cornell PhD student in Geophysics. The shrinking glaciers have discovered at least one new island, he added.

From 1953 to 2010, the average rate of ice surface loss was 18 centimeters per year. From 2011 to 2015, the decline in the ice surface was 32 centimeters (13 inches) per year, equivalent to a water loss of 4.43 gigatons per year, Zheng said. In perspective, so much water would raise the level of Cayuga Lake (the longest of the 38-mile New York Finger Lakes) and flood the cities of Ithaca and Seneca Falls.

The Arctic has been warming up lately for decades, but glaciers in the region react in different ways. "Previous studies have shown that glaciers in northern Canada seem to shrink faster than in some parts of northern Russia," said lead author Matt Pritchard, Cornell professor of geophysics.

"Our work is coming closer Look at the Russian glaciers to understand why they react differently to a warming Arctic than glaciers in other parts of the Arctic: Why are the glaciers in Franz Josef Land faster between 2011 and 2015? As in previous decades, temperature changes have dropped, "said Pritchard.

Zheng said a scientific saying that the glacier change in the Arctic should be slow, because the temperatures are low, the ice is very cold and melts slower than elsewhere. "We find that ice is changing faster than we thought before," Zheng said. "The temperature in the Arctic is changing faster than anywhere else in the world."

Co-author Michael Willis, assistant professor of geoscience and former research scientist at the Cornell University of Colorado, helped Zheng process the satellite data on paper, "Accelerated Glacier Mass Loss on Franz Josef Land, Russian Arctic."

Other co-authors include Paul Tepes, University of Edinburgh, Scotland; Noel Gourmelen, Université de Strasbourg, France; and Toby Benham and Julian Dowdeswell, University of Cambridge, England.


Further information:
Canadian glaciers contribute significantly to the sea-level change today

Further information:
Whyjay Zheng et al. Accelerated Glacier Mass Loss on Franz Josef Land, Russian Arctic, Remote Sensing of the Environment (2018). DOI: 10.1016 / j.rs.2018.04.004

Provided by:
Cornell University


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