Researchers have discovered a surprising fact about the Ross Ice Shelf in Antarctica: it moves forward several centimeters once or twice a day due to the Whillans Ice Stream, a fast-moving river of ice. This revelation highlights an unknown aspect of ice shelf dynamics and raises concerns about its long-term stability in the face of climate change.
Published in Geophysical Research Letters, the study reveals that the Whillans Ice Stream exhibits stop-and-go motion, unlike most glaciers that move slowly. The lack of water lubrication beneath the stream may cause it to intermittently stick and release built-up pressure in sudden bursts. These sudden shifts exert pressure on the Ross Ice Shelf, similar to tremors along earthquake faults.
While daily movements are not directly linked to human-induced warming, they could contribute to weakening the Ross Ice Shelf. Ice shelves act as barriers, slowing the flow of glaciers and ice streams into the ocean. If the Ross Ice Shelf weakens and breaks apart, it could accelerate ice melt rates and sea level rise. Scientists are closely monitoring the situation.
The research team emphasizes that icequakes and fractures are natural events on ice shelves but will be vigilant in observing the Ross Ice Shelf for signs of disintegration, similar to past occurrences with smaller ice shelves. This study underscores the complex and dynamic nature of Antarctic ice shelves and highlights the need for ongoing research to understand their future under a changing climate.