Antarctica is on course to lose more ice than it gains this century regardless of whether humanity meets its most ambitious climate targets, according to a new study published in the journal Nature Geoscience. The findings suggest that extra snowfall from warmer, wetter air — long considered a potential counterweight to ice loss — will not be enough to offset the melting driven by warming oceans, dealing a blow to hopes that Antarctica’s contribution to sea-level rise could be limited in the near term.
The frozen continent holds enough ice to raise global sea levels by approximately 190 feet (58 meters). Around 1 billion people currently live in coastal areas, with roughly 100 million living within one meter of sea level. The research team, comprising data scientists, glaciologists, and oceanographers, used a machine-learning model trained on a large international archive of Antarctic ice simulations to rapidly test hundreds of thousands of possible futures — a scale of analysis previously impossible due to the computing time required for individual simulations. Results were then filtered against two decades of satellite data tracking changes in the ice sheet’s mass. Only scenarios consistent with observed changes since 2002 were retained, and they all pointed in the same direction: net ice loss.
The study identifies three physical factors as most consequential for projecting future sea-level rise from Antarctica: how ice shelves respond to a warming ocean, how ice slides over the underlying bedrock, and how quickly the surrounding ocean and atmosphere warm.
In a high-emissions scenario, the researchers describe a potential cascade in which warming oceans thin ice shelves, weakened shelves break apart, and glaciers behind them accelerate into the sea. That chain of events could contribute up to 10 inches (25 centimeters) of sea-level rise from Antarctica alone by 2100 — enough to permanently flood the homes of more than 10 million people.Even under the Paris Agreement’s most ambitious 1.5°C target, Antarctica is projected to add to the sea-level rise already being driven by the melting Greenland ice sheet, mountain glaciers, and the thermal expansion of warming ocean water.
The researchers are clear about the limits of their findings. Several processes — including how ice fractures and breaks, and how subglacial lakes and rivers evolve — are not yet captured in existing simulations, meaning the machine-learning model cannot account for them. These gaps could alter projections of how quickly Antarctic ice reaches the sea. Nevertheless, the study’s authors say the work provides a faster and more systematic way to evaluate the range of plausible futures, offering a stronger scientific foundation for the planning decisions that coastal communities around the world are already being forced to make.