A newly discovered subglacial water network is playing a significant role in how Antarctica’s ice sheets move toward the ocean. Using advanced computer models, researchers have mapped the hidden plumbing system beneath the Antarctic ice sheet, revealing how water channels influence glacier speed and contribute to sea level rise.
The study, published in Geophysical Research Letters, highlights the importance of subglacial hydrology in shaping ice dynamics. “The model has revealed that the lowest effective pressures are in the interior of the continent and under the outlet glaciers along the ice sheet’s edge,” the researchers noted. This means that ice is moving more quickly, raising concerns about the long-term stability of the West Antarctic Ice Sheet.
How Water Beneath the Ice Is Reshaping Antarctica
Deep beneath the Antarctic ice, pressurized water is actively altering the movement of glaciers. The study, led by Shivani Ehrenfeucht, a glaciologist at the Georgia Institute of Technology, combines two computational models to better understand how subglacial water networks influence the Antarctic ice sheet’s movement.
The researchers merged the Glacier Drainage System Model, which tracks the movement of water under ice sheets, with the Ice-sheet and Sea-level System Model, which simulates how glaciers flow and change in response to climate factors. The result is a comprehensive map of Antarctica’s hidden water systems, showing how underground channels shape ice flow.
Neil Ross, a geophysicist at Newcastle University who was not involved in the study, explains that the new model allows scientists to “identify where water is underneath the ice, or model where the water would be underneath the ice, where it’s particularly thick and the pressures are high enough to enable the ice to slide and to flow faster.”
The Connection Between Ice Shelves and Accelerating Melt
The study also underscores the critical role of Antarctica’s floating ice shelves, which act as natural barriers slowing the movement of ice toward the ocean. However, these shelves are melting at an alarming rate, weakening their ability to hold back glaciers.
“If these platforms of ice melt, more ice could flow from the bedrock into the ocean and contribute to sea level rise,” researchers noted. Many of the newly identified subglacial channels align with areas where ice shelves are already thinning due to warm ocean currents, suggesting that freshwater flow from these channels could be speeding up ice loss.
The model accurately predicted the locations of several known subglacial lakes in West Antarctica, as well as large underground water channels that transport melted ice to the ocean. Some of these channels, researchers suggest, may be contributing to the rapid melt rates observed along the Amundsen Sea Embayment, a region already experiencing significant glacial retreat.
An Urgent Warning for the Future
Current projections estimate that Antarctic ice loss could raise global sea levels by up to 30 centimeters (12 inches) by 2100. This new study suggests that the process may be happening faster than previously expected, as the presence of extensive underground water networks could be accelerating ice movement toward the ocean.
Rupert Gladstone, a glaciologist at the University of Lapland in Finland, explains that as subglacial pressure decreases, ice becomes more mobile. “As that approaches zero, we’re approaching the situation where the ice is basically free, floating on the base of water,” he said.
The discovery of this hidden Antarctic plumbing system is a major breakthrough in glacial research, shedding light on how subglacial water dynamics influence the future of ice sheets. Scientists now plan to conduct further field studies to verify the model’s predictions and determine whether similar subglacial water networks exist in other polar regions.
The study is published in Geophysical Research Letters.
