The Vavilov dome, slipping into the sea glacier on the Northern Earth in the Russian Arctic, has accelerated several tens of times to 25 meters a day since 2015, having lost 4.5 cubic kilometers of ice a year. This is reported by an international group of scientists whose article is published in the journal Earth and Planetary Science Letters.
The glacial dome of Vavilov is on the island of the October Revolution of the archipelago of the Northern Earth, and its language from the west side is gradually pushed into the sea. The authors of the article write that the speed with which this occurs recently has not previously been observed on any glacier, and this raises doubts that other glaciers that are now stable and can not undergo the same mass loss.
“In the warming climate, the acceleration of glaciers is increasing, but the rate of ice loss on the Vavilov dome is extreme and unprecedented … We have never seen anything like this, and we had as many new issues as we managed to resolve. Now we are working on a model of this situation to better understand the physics of what is happening, “said study lead author Mike Willis of the University of Colorado in Boulder, whose words are cited by the press office.
Scientists used images of the company’s DigitalGlobe satellites in order to assess the speed of the glacier’s tongue. They found out that until 2010 the glacier moved slowly, several centimeters per day, after which it began to accelerate gradually and by 2015 “accelerated” to 25 meters per day. The authors of the article believe that the acceleration of a normally stable glacier, protected from precipitation by the dry climate of the polar desert, was due to the fact that his tongue moved to more slippery bottom sediments and began to accelerate, gradually podaplivaya water under the glacier, which, in turn, still more accelerated it (so there is a positive feedback).
Now the glacier is moving at a speed of 5 to 10 meters per day. If 30 years before the acceleration, he advanced two kilometers and lost approximately 1.2 cubic kilometers of volume, then in one year from 2015 to 2016 he advanced four kilometers, became approximately 100 meters thinner and lost 4.5 cubic kilometers of ice. Scientists warn that due to climate change and warming in the Arctic, Vavilov’s cupola is unlikely to recover the lost mass of ice.
Simultaneously with the international research, a Russian publication is being prepared for publication, about which N + 1 was told by its co-author, a leading researcher of the Glaciology Department of the Institute of Geography of the Russian Academy of Sciences Gennady Nosenko. The materials provided by Nosenko say that Russian scientists analyzed 28 space images taken between 1963 and 2017, airborne radar data and literature.
According to estimates by Russian scientists, the gradual acceleration of the glacier began as early as the 1980s, when from 12 meters per year it passed to 100 meters a year at the beginning of the two thousandths. The maximum rate of glacier advance – 9.2 kilometers per year – was recorded in 2016. “From 1963 to 2017, the edge of the glacier advanced by 11.7 kilometers, and its area increased by 134.1 square kilometers (47 percent relative to the area in 1963), which was accompanied by the spreading up the glacier of the zone of tension cracks,” it says in the article.
Scientists from the Institute of Geography of the Russian Academy of Sciences also suggest that the acceleration of the glacier was associated with unstable marine sediments and positive feedback from the water under the glacier. In addition, the increase in speed contributed to the abnormally warm 2012.
Earlier climatologists from Austria and Germany showed that at the current level of the average annual temperature of the atmosphere, the volume of glaciers is very far from the steady state. This means that measures to reduce greenhouse gas emissions will not stop the melting of glaciers, but will only slow it down a little.