An international group of scientists from the IMBIE project (Ice Sheet Mass Balance Inter-comparison Exercise) used the longest satellite observation record to date of changes in ice sheets and published the study in the journal Scientific Data. The authors call it the most complete picture to date of ice loss in Greenland and Antarctica and a new confirmation of the consequences of human-caused climate change.
From 1979 to 2023, according to data from 27 satellite missions, Greenland and Antarctica lost a total of 11.3 trillion tons of ice. Greenland accounted for about 60% of these losses, Antarctica for about 40%, although Greenland is roughly eight times smaller than Antarctica, and the melting is equivalent to a 3.14 cm rise in sea level worldwide.
The lead author of the study, climate scientist Ines Otosaka of Northumbria University in England, said that 11.3 trillion tons of ice would be enough to fill a cube 23 km high. She also noted that ice sheets now account for about 25% of all sea-level rise.
According to Otosaka, every additional centimeter of sea-level rise increases the annual risk of coastal flooding for 2–3 million people, and the combined contribution of ice loss in Greenland and Antarctica poses a flood and erosion threat to 6–9 million people worldwide. The scientists extended the satellite record back to the 1970s and concluded that ice loss began in the 1990s and has been increasing ever since, while the rate of melting between the 1980s and 2010s quadrupled.
The study also recorded a slowdown in losses in 2020–2023, but the authors consider it a short-term fluctuation rather than a reversal of the long-term trend. They pointed out that unusually heavy snowfall in East Antarctica offset part of the losses in other parts of the continent, while a relatively mild summer in Greenland reduced surface melting. At the same time, 84% of the lost ice came not from surface melting, but from accelerated glacier flow into the ocean, showing the decisive role of ice sheet response to ocean warming.
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