A new study has revealed an intriguing phenomenon in Antarctica, showing that the massive Ross Ice Shelf moves forward several centimetres once or twice a day. This movement is caused by the Whillans Ice Stream, a fast-flowing river of ice that occasionally becomes stuck and then surges ahead. This discovery sheds light on a previously unknown aspect of ice shelf dynamics and raises concerns about the long-term stability of the Ross Ice Shelf in the face of climate change.
Published in Geophysical Research Letters, the research highlights that unlike most glaciers that move slowly, the Whillans Ice Stream experiences a stop-and-go motion. The lack of water lubrication beneath the stream may be causing it to intermittently stick and release built-up pressure in sudden bursts, pushing against the Ross Ice Shelf.
Although the daily movements are not directly linked to human-caused warming, they could potentially weaken the Ross Ice Shelf. Ice shelves play a crucial role in slowing the flow of glaciers and ice streams into the ocean, so any weakening or breaking apart of the Ross Ice Shelf could accelerate ice melt rates and contribute to sea level rise.
The research team is closely monitoring the situation, emphasizing that icequakes and fractures are natural occurrences on ice shelves. However, they will be vigilant for any signs of disintegration, similar to what has happened to smaller ice shelves in the past. This study underscores the complex and dynamic nature of Antarctic ice shelves and highlights the importance of continued research to understand their future under the changing climate.