Scientists Detect 360 Hidden Earthquakes From Collapsing Antarctic Icebergs
Finn's Take· TL;DR- Scientists detected 360 previously unknown earthquakes from collapsing icebergs at Thwaites Glacier using new seismic monitoring methods on Antarctica.
- Thwaites Glacier could raise sea levels by 3 meters if it collapses and trigger a chain reaction destabilizing West Antarctica.
- Glacial earthquakes produce low-frequency seismic waves invisible to traditional detection, providing crucial data satellites alone cannot capture about ice instability.
The Sound of Ice Collapse
Deep beneath Antarctica's frozen landscape, the seismic echoes of capsizing icebergs falling from Thwaites Glacier have been detected for the first time . These aren't ordinary earthquakes caused by shifting tectonic plates. Instead, they're the violent reverberations of massive ice chunks breaking away from one of Earth's most dangerous glaciers, then capsizing and clashing violently with the "mother" glacier, generating strong mechanical ground vibrations that propagate thousands of kilometres from the origin .
Using a revolutionary approach, researcher Thanh-Son Pham placed seismic detectors directly on Antarctica rather than relying on distant global networks. His search turned up more than 360 glacier seismic events, most of which are not yet included in any earthquake catalogue . About two-thirds of the events – 245 out of 362 – were located near the marine end of Thwaites , the glacier scientists ominously call the "Doomsday Glacier."
Why This Glacier Matters
If it were to collapse completely it would raise global sea levels by 3 meters (10 feet), and it also has the potential to fall apart rapidly . But Thwaites isn't just massive—it's strategically positioned as a natural dam. The glacier currently helps hold back neighbouring ice systems; its failure could trigger a chain reaction, leading to far greater ice loss across West Antarctica .
What makes these newly detected earthquakes particularly alarming is their timing. The most prolific period of glacial earthquakes at Thwaites, between 2018 and 2020, coincides with a period of accelerated flow of the glacier's ice tongue towards the sea . Unlike Greenland's glacial earthquakes, which follow predictable seasonal patterns, the glacial earthquakes near Thwaites seem to take place in parallel with a period of accelerated flow of the glacier's ice tongue toward the sea rather than simply responding to warmer air temperatures.
The Science Behind Ice Quakes
A glacial earthquake is created when tall, thin icebergs fall off the end of a glacier into the ocean. What makes glacial earthquakes unique is that they do not generate any high-frequency seismic waves . This characteristic made them nearly invisible to traditional earthquake detection methods until scientists learned what to listen for.
Glacial earthquakes are a newly discovered type of seismic event that produces low-frequency waves, with a magnitude of around 5. They were first detected in 2003 and are mainly caused by the collapse of large icebergs . The phenomenon was initially discovered in Greenland, but scientists assumed that glacial earthquakes take place in Antarctica as well, they have been much harder to detect because they are of much lower magnitude than those that occur in Greenland .
Looking Ahead
The discovery opens new possibilities for monitoring Antarctica's rapidly changing ice sheet. The newly detected earthquakes provide a rare window into processes that satellites alone cannot fully capture. While satellite images can show surface changes and ice speed, they cannot "hear" what is happening when icebergs detach, roll, and collide with the ocean. Seismic data fills this gap .
The detection of glacial earthquakes associated with iceberg calving at Thwaites Glacier could help answer several important research questions. These include a fundamental question about the potential instability of the Thwaites Glacier due to the interaction of the ocean, ice and solid ground near where it meets the sea. Better understanding may hold the key to resolving the current large uncertainty in the projected sea-level rise over the next couple of centuries .
As ocean temperatures continue rising and ice sheets respond in increasingly unpredictable ways, these seismic signatures may become our early warning system for catastrophic ice loss. The hundreds of hidden earthquakes now revealed suggest that Antarctica's transformation is happening faster and more dramatically than satellites alone could show us.