A new scientific atlas has just redrawn the map of Antarctica’s seafloor—and what it reveals could alter how researchers model sea-level rise, ocean circulation, and the continent’s past. The study, published in Marine Geology and led by researchers from the University of Barcelona and University College Cork, identifies 332 previously unmapped submarine canyons hiding beneath the Antarctic margin—five times more than previously recognized.
This extensive canyon system, now the most detailed of its kind, opens a new window into how ice sheets and deep ocean dynamics have shaped the polar environment over millions of years—and how they continue to influence global climate systems today.
Mapping the Unseen Depths of Antarctica
Using high-resolution bathymetric data collected from over 40 international expeditions, the researchers compiled the first standardized and continent-wide map of Antarctica’s submarine canyon networks. Many of these deep underwater features remained undetected until now due to the challenges of collecting sonar data beneath floating ice shelves and over vast, remote regions.
Some of the newly identified canyons plunge to depths of over 4,000 meters, acting as underwater highways that funnel sediments, nutrients, and water masses between the continental shelf and the deep ocean. Their size and complexity, scientists say, match or exceed some of the planet’s largest known submarine canyons.
“This is the first time we have a coherent view of these systems across the entire Antarctic margin,” said Dr. David Amblàs from the University of Barcelona. “These features are not only widespread, but they are deeply connected to past and present ice dynamics.”
East vs. West: A Tale of Two Antarctic Landscapes
The study shows a clear contrast between East and West Antarctica—a difference that could be key to understanding how each region has responded to past climate changes. In the eastern part, canyon systems are often branched and extensive, with multiple tributary channels merging into a main path. This configuration suggests a long geological history, shaped by stable, persistent ice sheets.
On the other hand, the western margin features canyons that are steeper, straighter, and shorter—signs of more recent or episodic glacial activity. This aligns with current scientific models showing that West Antarctica has experienced more dynamic ice movement and is currently more vulnerable to rapid melting.
According to co-author Dr. Alan Condron from Woods Hole Oceanographic Institution, these structural differences help scientists “reconstruct the ice flow history” and refine models used to predict how these massive ice systems may respond to warming temperatures.
Why These Canyons Matter for the Planet’s Oceans
Beyond their geological interest, the submarine canyons play a crucial role in how Antarctic waters move and mix. Acting as conduits, they channel dense, salty water formed on the continental shelf into the deeper parts of the Southern Ocean. This process drives global thermohaline circulation, which in turn regulates temperatures and nutrient distribution across vast swaths of the planet’s oceans.
But the movement isn’t one-way. Warm water from deeper ocean layers can also travel up the canyons, reaching under ice shelves and accelerating melting from below. This interaction is now seen as a key factor in the destabilization of ice shelves, particularly in West Antarctica.
“This canyon-driven water exchange is not a minor side process—it’s central to how heat reaches the ice and how fresh meltwater escapes into the ocean,” explained Dr. Condron.
Feeding Better Data Into Climate Models
With climate models increasingly focused on regional processes, the newly revealed canyon systems provide a missing piece of the puzzle. Until now, many models simplified Antarctica’s seafloor as relatively featureless, failing to account for how submarine topography shapes water movement, sediment flow, and ice-ocean interactions.
This detailed map changes that. By incorporating the shape, depth, and layout of these canyon networks into predictive simulations, scientists can now more accurately estimate how ice loss might progress—and how quickly it might contribute to global sea-level rise.
According to the research team, this isn’t just about understanding the past. These canyons could determine whether melting from inland glaciers reaches the ocean quickly or stays locked in place. That distinction has real consequences for coastal cities and ecosystems worldwide.
Source link
