Recently, a study published in Geophysical Research Letters showed that scientists discovered hundreds of previously unrecorded icequakes in Antarctica, and most of the events occurred near the Thwaites Glacier, which is undergoing rapid change.
Icequakes are the mechanical vibrations caused to the ground when huge chunks of ice break off the edge of a glacier and crash into the ocean. Although these seismic signals have been monitored in the Northern Hemisphere for many years, the detection of such activities in Antarctica has been slow due to technical difficulties. Researchers from the Australian National University successfully identified more than 360 icequake events that occurred between 2010 and 2023 by using local seismic stations in Antarctica.
Thwaites Glacier has been nicknamed the "Doomsday Glacier" because of its potentially huge impact on sea level rise. The study found that of the 362 events monitored, about two-thirds occurred on the ocean side of Thwaites Glacier. Different from the seasonal pattern that icequakes often show in the Northern Hemisphere, the active period of icequakes at Thwaites Glacier is highly consistent with the phase when the ice tongue accelerates towards the ocean, which indicates that marine environmental conditions may have a short-term dramatic impact on the stability of the glacier. In addition, the study also detected another icequake cluster near Pine Island Glacier, but because it is far away from the coastline, its cause still needs to be further explored.
This discovery provides new data support for researchers to evaluate the stability of the "Doomsday Glacier". Experts believe that deepening the understanding of the interaction between glaciers, oceans, and solid ground will help reduce the prediction bias of sea level rise in the next few centuries, and is of great significance for addressing the challenges posed by global climate change.