Greenland and Antarctica have lost 11.3 trillion tonnes of ice between 1979 and 2023, contributing 3.14 centimetres to global sea-level rise, according to a new analysis published in Scientific Data.
The findings come from the Ice Sheet Mass Balance Intercomparison Exercise (IMBIE), an international collaboration supported by the European Space Agency (ESA) and NASA that combines and reconciles measurements from multiple satellite missions to build a long-term record of ice-sheet change.
IMBIE researchers drew on data from 27 satellite missions and analysed 42 independent surveys, producing a record that goes back to 1972 for Greenland and 1979 for Antarctica. The work aims to make different observational methods comparable, including satellite altimetry, gravity measurements, and radar and optical tracking of glacier movement.
While surface melting is widely associated with ice loss, the study reports that most of the long-term decline has been driven by faster glacier flow. According to the analysis, 84% of the combined ice loss was due to glaciers accelerating and discharging more ice into the ocean, while 16% was caused by surface melting.
Inès Otosaka from Northumbria University, who led the study, said, “By reaching back to the 1970s, we can now see how the ice sheets have changed across half a century. More than four-fifths of the ice lost was discharged into the ocean by faster-flowing glaciers, rather than melted at the surface – which tells us the long-term trend is being driven by the dynamic response of the ice sheets to a warming ocean.”
The study found Greenland contributed 1.81 centimetres of sea-level rise over the period examined, compared with 1.33 centimetres from Antarctica. It also states that together the two ice sheets are now responsible for around a quarter of global sea-level rise.
Andrew Shepherd, also from Northumbria University and founder of IMBIE, said, “Just over three centimetres of sea-level rise may sound small, but that puts another six to nine million people at risk of coastal flooding and erosion. With the ice sheets set to lose much more ice in the decades ahead, global assessments like IMBIE are vital to protecting communities impacted by climate change.”
The analysis indicates ice losses accelerated from the 1990s. It reports Greenland’s annual ice loss rose from around 60 billion tonnes in the 1980s to 264 billion tonnes in the 2010s, while Antarctica’s annual losses increased from around 48 billion tonnes to 202 billion tonnes over the same periods.
The study also notes a recent slowdown in overall ice loss from 2020 to 2023, attributed to unusually high snowfall in East Antarctica and relatively mild summers in Greenland reducing surface melt. Researchers caution that these patterns represent short-term variability rather than a reversal, with the ice sheets still in net loss overall.
Beyond historical accounting, the findings highlight ongoing uncertainty in sea-level projections. The report states that high-end estimates of global sea-level rise by 2150 increase by a factor of 2.6 when the risk of ice-sheet instability is included, underscoring the importance of sustained satellite monitoring and long-term climate datasets.
ESA’s Clement Albergel said, “The ability to assess the present-day state of our planet’s ice sheets and understand the dominant drivers of change so comprehensively, is only possible through sustained Earth observation and the long-term climate data records developed through research programmes such as ESA’s Climate Change Initiative.”
ESA’s Diego Fernandez said, “These findings demonstrate the fundamental importance of international scientific collaboration in addressing the major environmental changes of our time. In the years ahead, novel missions such as CRISTAL and ROSE-L will be critical to building on this work, enabling advanced monitoring of the rapid changes now affecting ice sheets and helping us better understand an evolving climate system in which abrupt and irreversible change can no longer be ruled out.”
