A new, long-term analysis shows Greenland and Antarctica are losing most ice not mainly from surface melting, but because glaciers are flowing faster into the ocean, with Ocean-driven melt driving much of the loss in Antarctica.

About 84 percent of the observed acceleration in ice loss since the 1980s is due to faster glacier flow, while 16 percent comes from surface melt, indicating a larger role for ocean-driven processes than previously thought.

Greenland’s mass loss in the 2010s was shaped by significant surface melt, but two-thirds of total loss came from discharge into the ocean.

The upward trend in ice loss is robust, confirmed across 45 surveys and 27 satellites, strengthening confidence in the findings.

Future work will focus on regional-scale analyses to map spatial differences in how ice sheets respond to climate factors.

scientists warn of potential tipping points and abrupt, nonlinear ice-sheet changes that could accelerate sea-level rise and complicate coastal risk planning.

Key instabilities of concern include marine ice sheet instability and marine ice cliff instability, which could drive large future losses, especially in Antarctica.

While the exact trajectory remains uncertain, the long-term trend of rising ice loss underscores the urgency of addressing climate change.

Melt accelerated notably in the 2010s, with a temporary lull around 2020–2023 due to weather variations, though the upward trend resumed afterward.

A temporary slowdown from 2020 to 2023 occurred due to record snowfall in East Antarctica and milder Greenland summers, but the underlying trend of increasing discharge persists.

Researchers say the acceleration has resumed after the lull, indicating a persistent upward trajectory in ice loss.

The study, conducted by an international collaboration led by the European Space Agency and using NASA satellite data, extends Greenland ice records back to the early 1970s and Antarctica back to the late 1970s.