Record-Breaking Glacier Collapse in Antarctica: The Fastest in History Revealed!

A glacier on the eastern Antarctic Peninsula has made headlines for breaking speed records. The Hektoria Glacier retreated about five miles (8 kilometers) in just two months in late 2022, marking the fastest-known modern collapse of any grounded Antarctic glacier.

Research from Naomi Ochwat, a postdoctoral researcher at the Cooperative Institute for Research in Environmental Sciences, explains how this collapse happened. The glacier became buoyant over a flat seabed, causing it to break apart in big chunks. In November and December 2022, it retreated at a staggering rate of roughly half a mile per day.

Ochwat noted the alarming extent of the collapse when she and her team flew over Hektoria in early 2024. “If we only had one image every three months, we might not have realized how much ice had been lost,” she said.

Factors Behind the Collapse

The glacier’s rapid retreat can be linked to its grounding line—the point where it meets the seafloor. When this line shifts due to thinning ice or tides, it can destabilize the entire glacier. As Hektoria thinned enough to float, gravity and buoyancy led to its rapid fragmentation. Six glacial earthquakes were recorded, indicating significant ice movement and the breakage of large icebergs.

Satellite data revealed a sixfold increase in the glacier’s flow speed as it destabilized. Laser measurements showed thinning reaching about 262 feet (80 meters) per year. Interestingly, this retreat wasn’t driven by unusually warm ocean water; it was more about the loss of local fast ice, which usually helps stabilize the glacier by damping waves.

Historically, this isn’t the first time we’ve seen similar collapses. In 2002, the Larsen B Ice Shelf collapsed, leading to accelerated melting of tributary glaciers. Studies have shown that such shelf losses can prompt glaciers to thin and speed up their flow into the ocean.

Implications for Sea Levels

Though Hektoria isn’t the largest glacier in Antarctica, its rapid collapse raises concerns about sea-level rise. Ice plains like the one beneath Hektoria are found under several key glaciers. Past findings show that grounding line retreats can happen incredibly quickly—up to 2,000 feet per day in extreme cases.

Ted Scambos, a senior research scientist at CIRES, warns that similar conditions under larger glaciers could lead to significant sea-level increases sooner than expected.

Looking Ahead

Researchers are now focused on identifying other glaciers on flat beds beneath Antarctica. Using radar and satellite data, they hope to locate these “early-warning zones” where small changes could lead to large-scale collapses.

Models that predict glacier behavior need to account for sudden buoyancy events and possible surges in motion. Understanding these dynamics better could shift projections for sea-level rise by decades, especially for regions like West Antarctica that are near a tipping point.

By paying attention to how local ice dynamics, such as sea ice and ice mélange, return or vanish, scientists can better predict glacier behavior. This knowledge is integral to adjusting our approach to glacier modeling—addressing how they might rapidly collapse under the right (or rather, wrong) conditions.

The results of this research were published in Nature Geoscience. For more details, you can check the full study here.

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