The second largest ice sheet on Earth is melting extremely

For the study, the scientists compared the altitude measurements of the satellite missions CryoSat-2 of the European Space Agency (ESA) and ICESat-2 of the American space agency NASA for the first time.

CryoSat-2 measures the height of the ice on the Greenland ice sheet using radar, while ICE-Sat-2 uses laser. Radar has the advantage that it penetrates clouds, so it can also be used when the sky is cloudy.

However, the radar frequencies used penetrate snow surfaces up to ten meters, making the measurement relatively inaccurate and requiring improvement through correction calculations. The laser, on the other hand, measures the snow and ice surface quite accurately, but only when the sky is virtually cloudless. Since the start of the ICESat-2 mission in 2018, there have been parallel measurements of both systems.

Overall, the differences explain only about six percent of the observed trend.

Reduction of the ice height by 11.6 centimeters
Using measurement data from the two satellite systems from 2018 to 2022, researchers determined an average decrease in ice height of 11.6 centimeters per year across the entire ice sheet. However, this melting was very unevenly distributed: in the large inner area it was only 6.3 centimeters, in the peripheral areas 54.3 centimeters, so about nine times as much.

Further findings:

• For the period 2010 to 2022, scientists calculated an average annual ice loss of 79 cubic kilometers inland and 117 cubic kilometers in peripheral areas.

• This total of 196 cubic kilometers per year results in a volume loss of 2,352 cubic kilometers for the entire study period. This is almost the same amount of water as Africa’s largest lake, Lake Victoria, with a volume of 2,760 cubic kilometers.

• According to a 2023 study, melting Greenland ice has caused global sea levels to rise by 13.6 millimeters since 1992.