The Greenland ice sheet is shrinking by an average of 196 cubic kilometers per year, with a peak of 464 cubic kilometers between 2010 and 2022, a research team from the University of Leeds reports in the journal „Geophysical Research Letters".
For the study, scientists have for the first time analyzed height measurements from the satellites „CryoSat-2“ of the European Space Agency ESA and „ICESat-2“ of the American space agency NASA. „CryoSat-2“ uses radar to measure the height of the ice on the Greenland ice sheet, and „ICE-Sat-2" - lasers.
The advantage of radar radiation is that it penetrates through clouds, which means that it can also be used when the sky is cloudy. However, the radar frequencies used penetrate up to ten meters into the snow surfaces, which makes the measurement relatively inaccurate and requires correction calculations. The laser, on the other hand, measures the surface of snow and ice quite accurately - but only when the sky is almost cloudless.
A big loss
Based on the data from the measurements of the two satellite systems, the researchers found that the height of the ice decreased during the period 2018 - 2022 by an average of 11.6 centimeters per year, with the melting being distributed very unevenly: in the large inner zone it was only 6.3 centimeters, and in the outer zones - 54.3 centimeters, i.e. about nine times more.
For the period 2010-2022, scientists calculated an average annual ice loss of 79 cubic km in the inner zone and 117 cubic km in the peripheral regions. This total of 196 cubic km per year results in a volume loss of 2,352 cubic km over the entire study period - almost as much as the volume of water in Africa's largest Lake Victoria.
According to a 2023 study, the melting of Greenland's ice has led to a rise in global sea levels of 13.6 millimeters since 1992. According to ESA calculations, the complete melting of this ice sheet would lead to a rise in sea levels of about seven meters.
"Greenland belongs to us"
Greenland is the second largest ice sheet on Earth - only Antarctica is larger. The sparsely populated Greenland is a largely autonomous part of the Kingdom of Denmark.
During his first term, future US President Donald Trump caused a stir with his intention for the US to buy the island. At the time, Greenland's Prime Minister Mute Borup Egede clarified that the island was not for sale: “Greenland belongs to us, it is not for sale and will never be for sale.“