Scientists record fastest Antarctic glacier retreat in modern history

A glacier on the eastern edge of the Antarctic Peninsula has undergone the fastest recorded retreat in modern history, losing nearly half its length in just two months, according to a landmark study co-authored by Swansea University researchers.

The findings, published in Nature Geoscience, reveal that Hektoria Glacier shed eight kilometres of ice at a pace not seen since the end of the last ice age.

The international research team, led by the University of Colorado Boulder, found that the glacier’s rapid retreat was driven by the shape of the land beneath it. Hektoria was resting on an “ice plain” — a flat bed of rock lying below sea level — which allowed large sections of ice to collapse once the retreat began.

Although Hektoria covers only 115 square miles, slightly smaller than the city of Swansea, scientists say its sudden collapse offers a stark warning. Similar conditions exist below much larger Antarctic glaciers, whose destabilisation could accelerate global sea level rise.

Professor Adrian Luckman, glaciologist at Swansea University and co-author of the study, said the observations were unprecedented. “Glaciers don’t usually retreat this fast,” he said. “The circumstances may be a little particular, but this scale of ice loss shows what may happen elsewhere in Antarctica, where glaciers are lightly grounded and sea ice loses its grip.”

He added that even the historical record offers few parallels. “Although the paleo record indicates some very rapid retreats in the past, the pace of retreat of Hektoria Glacier and its neighbours is unprecedented in the observational record. This is the latest chapter in a sequence of events which started with the collapse of the Larsen B Ice Shelf 23 years ago.”

Researchers used satellite imagery and seismic instruments to chart the glacier’s disintegration, identifying multiple grounding lines — the points where ice transitions from resting on land to floating at sea. Their movement underscored the vulnerability of ice plains to warming oceans. Seismic sensors also picked up “glacier earthquakes”: tremors linked to sudden, large-scale ice movement, confirming that grounded ice was being lost and directly contributing to rising seas.

Dr Ted Scambos, Senior Research Scientist at CU Boulder’s Earth Science and Observation Center, said the findings widened the scope of potential risk. “This kind of lightning-fast retreat really changes what’s possible for other, larger glaciers on the continent,” he said. “If the same conditions are set up in some of the other areas, it could greatly speed up sea level rise from the continent.”

You can read the full paper here.