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Antarctica's under-ice terrain mapped in unprecedented detail
A groundbreaking new map has exposed the rugged topography beneath Antarctica's ice sheet, uncovering thousands of previously unknown hills, ridges, and deep channels that could shape the continent's response to climate change.
How the map was created
Researchers combined satellite imagery of Antarctica's icy surface with physics-based models of glacier movement to reconstruct the hidden bedrock. The team, led by Dr. Helen Ockenden of the University of Grenoble-Alpes, compared their findings with sparse radar surveys conducted from aircraft and ground expeditions.
"Previously, we relied on isolated radar tracks spaced tens of kilometers apart, leaving vast gaps in our knowledge," said glaciologist Prof. Robert Bingham of the University of Edinburgh, a co-author of the study. "This new approach fills those gaps by interpreting how ice flows over buried landforms, much like reading ripples on a river to infer submerged rocks."
Discoveries beneath the ice
The map reveals a dramatic landscape of mountain ranges, canyons, and tens of thousands of previously undetected hills and ridges. Among the most striking findings is a massive channel in the Maud Subglacial Basin, averaging 50 meters deep, 6 kilometers wide, and stretching nearly 400 kilometers-comparable to the distance between London and Newcastle.
"It's akin to seeing Mars' topography for the first time," Ockenden told BBC News. "Some features resemble familiar landscapes like Scotland's Highlands, while others are entirely alien."
Implications for climate science
The hidden terrain plays a critical role in regulating glacier flow and retreat. Ridges can stabilize ice, while valleys may accelerate melting as temperatures rise. The new data will refine computer models predicting Antarctica's contribution to sea-level rise, a major uncertainty in climate projections.
"This map gives us a clearer picture of how Antarctica's ice will behave in the future and how rapidly it may melt,"
Dr. Peter Fretwell, British Antarctic Survey
Fretwell, who was not involved in the study but has contributed to prior mapping efforts, called the work "a valuable step forward" that bridges gaps between existing surveys.
Limitations and next steps
While the map is the most detailed to date, uncertainties remain due to assumptions about ice flow dynamics. The composition of rocks and sediments beneath the ice also requires further study. Future surveys-combining satellite, aerial, and ground-based methods-will continue to refine the picture.
The study was published in the journal Science.
