A vast and previously hidden world has been uncovered beneath Antarctica icy perimeter, revealing a network of 332 submarine canyons that are reshaping scientists’ understanding of ocean currents and the pace of global sea-level rise. A new, highly detailed map of the Antarctic seafloor, published in the journal Marine Geology, shows that these immense geological features are key conduits for the flow of water, heat, and sediment, directly influencing the melting of ice shelves.
A Dynamic Seafloor Revealed
The research, which utilized high-resolution bathymetric data from over 40 international expeditions, identified five times more canyons than had ever been catalogued before. The study found a dramatic contrast between the eastern and western margins of the continent.
East Antarctica is crisscrossed with complex, U-shaped canyons that suggest long-term glacial activity. In contrast, West Antarctica features shorter, steeper, and straighter canyons, a finding that supports models suggesting this region is more vulnerable to rapid melting, a major concern for future sea-level projections.
Climate Conveyor Belts
These submarine canyons are not just passive features; they act as dynamic conduits or “climate conveyer belts.” They funnel dense, salty water from the continental shelf into the deep Southern Ocean, a process critical for forming Antarctic Bottom Water, which powers the planet’s global thermohaline circulation.
However the canyons also have a more alarming role: they can carry warmer, deep-ocean water back toward the coast and underneath ice shelves, triggering basal melting from below. This process is already a major factor in the thinning of key glacial zones, which hold enough ice to significantly raise global sea levels.
The discovery has serious implications for climate modeling. According to the researchers, many current global sea-level projections have likely underestimated the pace and scale of ice loss by treating the Antarctic seafloor as relatively featureless. The new data will allow scientists to improve predictive models and provide more accurate risk assessments for coastal communities around the world.