For decades, scientists have worked to predict how fast Antarctica’s ice is melting—and how much it will raise global sea levels. But a hidden influence beneath the ice could be speeding up the flow of ice into the ocean.
New research published in
Nature Communications, reveals that water flowing beneath the Antarctic Ice Sheet, known as subglacial water, plays a much bigger role in ice loss than current models assume.
Streams of subglacial water in Antarctica come from melting at the base where it grinds against the bedrock. The water acts to lubricate the flow of the ice.
Computer models that are used to make projections about the future behaviour of the Antarctic Ice Sheet don’t include the physical processes controlling subglacial water, instead making assumptions about it’s properties.
“By directly comparing these different assumptions in one model, we found that projections can vary threefold. Our study highlights how these assumptions about subglacial water — particularly near the ice sheet margin where the grounded ice becomes floating — strongly influence sea-level rise projections.”, says
Rupert Gladstone who is one of the authors of the article.
The first author of the recent study
Chen Zhao says that without a realistic representation of the evolving properties of subglacial water, models may greatly over or underestimate the risks of ice loss and the timing of tipping points — critical thresholds where ice loss becomes unstoppable — by decades.
“As the world races to prepare for rising seas, integrating dynamic subglacial water systems into ice sheet models is more critical than ever.”, researchers conclude.
Open access article
Subglacial water amplifies Antarctic contributions to sea-level rise in Nature Communications 16, Article number: 3187 (2025).
More information:
Rupert Gladstone, University Researcher
Arctic Centre at the University of Lapland
rupert.gladstone(@)ulapland.fi