The study of survey materials taken on the surface of Antarctica, obtained using a laser device installed on the ICESat-2 satellite, showed the disappearance of a large lake in June 2019.
Where did the water in the amount of 600-750 million cubic meters disappear in less than a week. In its place, a crater-like depression formed with an area of about 11 square kilometers with an accumulation of broken ice that previously covered the surface of the lake.
In this basin, which scientists called the “Ice Valley”, in the summer season of 2020, meltwater began to collect again, forming a new lake, and it was found that its area is much smaller than the area of the previous lake. .
Researchers from the Scripps Institution of Oceanography at the University of California at San Diego and the Institute for Marine and Antarctic Studies at the University of Tasmania set out to reconstruct the history of events and explain such mysterious shifts on the surface of the icy continent.
Having studied all the observations, one way or another connected with the formation and disappearance of the lake, the experts came to the conclusion that the water accumulating in the deep lake opened a crack in the ice shelf under the lake and flowed into the ocean. This process is known as hydraulic fracturing.
The scientists explained that hydraulic fracturing is a fairly common phenomenon that leads to the collapse of small ice shelves on the Antarctic Peninsula, where meltwater forms small lakes on the surface of the glaciers during the austral summer. The above process was more complex, since the thickness of the Amiri glacier, on which the lake was formed, was about 1.4 km.
Researchers believe it’s too early to conclude that the lake’s drying up is linked to climate change. This sudden event appears to be the culmination of decades of meltwater accumulating and storing it under an insulating ice cap.
According to scientists, the future of the drained lake is still unclear. In the 2020 melt season, water began to accumulate again, but then its level decreased. Researchers believe that the crack under the lake opens from time to time.