Hundreds of Quakes Shake Antarctica’s Thwaites Glacier

Scientists have recorded hundreds of icequakes over the past decade near Antarctica, linked to the breaking and flipping of massive icebergs.

Seismologists have documented more than 360 icequakes in Antarctica between 2010 and 2023, with 245 of these concentrated near the Thwaites Glacier’s seaward edge, famously dubbed the “Doomsday Glacier.”

Icequakes occur when giant icebergs detach from the ice shelf, overturn, and crash into the continental ice, generating seismic waves that can travel vast distances. Unlike typical earthquakes, these icequakes lack high-frequency waves, making them difficult to detect through global seismic networks.

The latest study relied on data from local Antarctic seismic stations, capturing events that had previously gone unrecorded.

Similar icequake activity has been studied in Greenland, showing strong seasonal patterns that peak at the end of summer. However, Thwaites Glacier’s icequakes showed no direct correlation with seasonal air temperature changes.

The most intense activity was recorded between 2018 and 2020, coinciding with an accelerated flow of the glacier tongue toward the sea, confirmed by satellite imagery. Researchers suggest that oceanic processes, such as the influence of relatively warm water at the glacier’s base, may be the primary drivers behind iceberg detachment and the resulting icequakes.

A second cluster of seismic events was observed near Pine Island Glacier, though their origin remains unclear as the epicentres were tens of kilometres offshore.

Scientists stress that this data is crucial for assessing the stability of Thwaites Glacier, as its potential collapse could significantly raise global sea levels. They emphasise that further research is needed to understand how short-term ocean conditions affect glacial processes.