A glacier on the Eastern Antarctic Peninsula has experienced the quickest ice loss ever documented in modern times. Hektoria Glacier shortened by nearly half its length in just two months in 2023, shedding eight kilometers of ice. This rapid collapse, driven by its below-sea-level ice plain, raises concerns about accelerated sea level rise from larger Antarctic glaciers.
In 2023, Hektoria Glacier on the Eastern Antarctic Peninsula retreated at an unprecedented pace, losing nearly half its length in two months and shedding eight kilometers of ice, according to a study published in Nature Geoscience. The research, led by the University of Colorado Boulder and co-authored by Swansea University's Professor Adrian Luckman, highlights how the glacier's position on a flat, below-sea-level ice plain facilitated the rapid detachment of large ice slabs.
The glacier, which spans about 115 square miles—slightly smaller than Austin, Texas—had been stable until this event. Satellite images and seismic data revealed multiple grounding lines where the ice transitions from bedrock to floating on seawater, confirming the retreat involved grounded ice that directly contributes to sea level rise. Seismic measurements detected small glacier earthquakes from abrupt ice shifts, underscoring the grounded nature of the loss.
Professor Adrian Luckman explained: "Glaciers don't usually retreat this fast. 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 while past geological records show rapid retreats, "the pace of retreat of Hektoria Glacier and its neighbors is unprecedented in the observational record." This event follows the 2002 collapse of the Larsen B Ice Shelf, signaling ongoing instability in the region.
Dr. Ted Scambos, a senior research scientist at CU Boulder's Earth Science and Observation Center, warned: "This kind of lightning-fast retreat really changes what's possible for other, larger glaciers on the continent. If the same conditions are set up in some of the other areas, it could greatly speed up sea level rise from the continent."
The study emphasizes the need for continued monitoring of vulnerable glaciers to predict future ice loss and its global impacts.