A new study has found that Greenland and Antarctica have collectively lost 11.3 trillion metric tons of ice since the 1970s, contributing to a global sea level rise of more than 3 centimeters (1.2 inches) since 1979. This research, based on the longest satellite record assembled to date, shows that most of this ice loss has been caused by glaciers speeding up and releasing more ice into the ocean, rather than by surface melting. The Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE) Team, a group of international polar scientists, combined data from 42 independent satellite surveys and 27 satellite missions, with records dating back to 1972 for Greenland and 1979 for Antarctica. Between 1979 and 2023, the total ice loss amounted to 11,309 billion metric tons, with Greenland being the primary contributor. Antarctica added 13.3 millimeters (0.5 inches) to the sea level rise. About 84% of the combined ice loss was due to glaciers accelerating and discharging more ice into the ocean, while 16% resulted from surface melting. These ice sheets are now responsible for about a quarter of all global sea level rise. The study, led by researchers from Northumbria University, the University of Washington Applied Physics Laboratory, and supported by the European Space Agency (ESA) and NASA, was published in the journal Scientific Data. It found that ice loss has increased significantly since the 1990s. Greenland's rate of loss rose from about 60 billion metric tons per year in the 1980s to 264 billion metric tons in the 2010s. Similarly, Antarctica's rate increased from around 48 billion metric tons per year in the 1980s to 202 billion metric tons in the 2010s. West Antarctica, particularly the Pine Island and Thwaites glaciers, has seen a steady increase in ice discharge over each decade of the record. While the most recent years (2020–2023) saw a temporary slowdown in ice loss, scientists suggest this was due to record snowfall in East Antarctica and milder summers in Greenland. They caution, however, that these are short-term fluctuations and not a reversal of the long-term trend. The study highlights the central role of ice sheets in future sea level rise, noting that their response to a warming climate is the largest source of uncertainty in sea level projections. Including the risk of ice-sheet instability, high-end estimates of global sea level rise by 2150 could be up to 2.6 times higher than previously thought. The study also stresses the importance of continuing long-term satellite monitoring to better understand and predict risks for coastal communities. Scientists note that the melting of polar ice sheets is accelerating, with about five-sixths of the melt driven by warmer ocean waters rather than surface melting. Since 1979, global sea levels have risen by about 3.1 centimeters, with each additional centimeter putting 2 to 3 million more people at risk of flooding annually. The use of data from both European and NASA satellites has provided a more comprehensive historical analysis, showing that ice sheets were relatively stable in the 1970s, 1980s, and into the 1990s, but the rate of melting has increased significantly in the 2010s. Despite a temporary slowdown from 2020 to 2023, the trend of increasing ice loss has resumed, with scientists warning that dynamic processes like glacier acceleration could lead to sudden, irreversible changes in ice sheet stability.