In a fascinating revelation, researchers studying the Ross Ice Shelf in Antarctica have uncovered a phenomenon where elastic waves cause the entire sheet to lurch forward once or twice a day. This unexpected discovery sheds light on the dynamic nature of ice shelves and their response to changing environmental conditions.
The Ross Ice Shelf, the largest in Antarctica and roughly the size of France, experiences these significant movements triggered by the Whillans Ice Stream, a fast-flowing belt of ice in the West Antarctic Ice Sheet. Geophysicist Doug Wiens from Washington University in St. Louis explains that the entire shelf suddenly moves about 6 to 8 centimeters (2.4 to 3.1 inches) due to a slip on the ice stream that flows into it.
These slip events, akin to movements along fault lines before earthquakes, occur as pressure builds up when ice moves at different speeds across the stream and is then released. Despite the substantial movement, it happens over several minutes and is imperceptible without instrumentation, highlighting the importance of scientific monitoring.
The study, based on measurements taken by embedded seismographs in 2014, reveals that these slip events can cause movements of up to 40 centimeters in just a few minutes, impacting the stability of the Ross Ice Shelf. While not directly attributed to human-induced global warming, understanding these phenomena is crucial for assessing the long-term stability of Antarctic ice shelves amidst ongoing climate change.
The potential disintegration of the Ross Ice Shelf could have far-reaching consequences, affecting ice cover across the region and contributing to sea-level rise. As researchers continue to monitor these developments, the study underscores the need for ongoing research to comprehend the complexities of Antarctica’s ice dynamics and their implications for the planet’s future.
“At this point, icequakes and fractures are just part of the normal life of the ice shelf,” notes Wiens, emphasizing the need for vigilance in studying and protecting these vital components of Earth’s cryosphere.
Edited by Dr. Brijendra Kumar Mishra, (Founder- DiCAF)