The Arctic ice cap is destabilizing at an unprecedented rate

Satellite images revealing a destabilizing Arctic ice cap at an "unexpected and unprecedented" speed have led scientists to question the long-term stability of some of the Earth's polar ice caps.

An accelerated video using the images shows a portion of the Vavilov Ice Cap in northern Russia, thinning and slowly extending into the Kara Sea from 1985 to 2010, when the process began to take place. accelerate. Between 2015 and 2016, the deterioration has increased considerably and the ice front has spread over more than 5 kilometers into the sea.

The images and data appear in the multi-institutional and multinational study titled "Massive Destabilization of an Arctic Ice Cap," published in the journal Earth and Planetary Science Letters.

"The glacier has increased its speed by 300 to reach more than 20 meters per day in 2016. While some glaciers in the world are periodically deforming with similar increases, nothing has been recorded in Vavilov," said Matthew Pritchard, professor. Earth Science and Atmosphere, who co-authored the study with PhD students Whyjay Zheng and William Durkin.

The study was led by Michael Willis, an assistant professor of geological sciences at the University of Colorado, a former research associate at Cornell.

Unlike fast-moving glaciers, it is thought that ice caps that are primarily frozen at the source rock are stable and respond slowly to climate change. The rapid deterioration of Vavilov's ice cap has led scientists to wonder whether it was simply an anomaly or whether other polar ice caps might be subject to accelerated changes.

"On all the glaciers we examined in Russia, Vavilov really stands out as being abnormal. Given the geometry of the Vavilov Ice Cap, low annual mass losses and the lack of breaking records, it was a glacier that we expected to maintain, "Durkin said.

The research team reconstructed the deterioration of the ice cap using remote sensing technology from a constellation of satellites and high resolution topographic maps of the Arctic region.

The authors of the study believe that the accelerated change observed in the ice cap in 2010 began with a slow process, as the glacier progressed for decades from land to ocean. According to the research team, the bed beneath the offshore portion of the glacier probably consists of saturated marine sediments with a low coefficient of friction, which has accelerated the movement and leads to the glacier which is rapidly pouring into the sea from April 2015.

"Since 2016, the glacier has slowed down, but is still moving faster than its long-term average. We continue to monitor the glacier and develop models of what happened and what could be the future of the ice cap, "said Pritchard, who added that the Vavilov may not be able to recover. its previous state due to global warming of the Earth.

According to the study, glaciers and ice caps at high latitudes cover about 450,000 square kilometers of the planet and retain a 30-centimeter increase potential of the sea level. The Vavilov ice cap has lost about 4.5 cubic kilometers of equivalent water between 2015 and 2016. This represents about half the volume of Cayuga Lake, or enough water to provide about 370 years of domestic use of the lake. water to the metropolitan area of ​​Ithaca, according to the research team. .

Syl Kacapyr is responsible for public relations and content for the College of Engineering.