An international group of scientists, led by **David Amblàs**, from the **Consolidated Research Group in Marine Geosciences at the University of Barcelona**, together with **Riccardo Arosio**, from the **University College Cork (Ireland)**, conducted the most comprehensive survey to date of **submarine canyons in the Antarctic region**, revealing the existence of **332 formations**, five times more than previously estimated.
This discovery, based on **high-resolution bathymetric data**, substantially modifies the current knowledge about the **seafloor topography in the Southern Ocean**, with relevant implications for **ocean circulation, glacier melting**, and ultimately, the evolution of **global climate change**.
## Submarine canyons as sediment and energy corridors
**Submarine canyons** are **steep depressions on the ocean floor** through which **sediments, nutrients, and marine currents** flow.
Globally, over **10,000 canyons** have been recorded, although only **27% of the ocean floor** has been mapped with sufficient precision. It is likely that their actual number is significantly higher.
In the Antarctic region, researchers found that these structures are **more extensive, numerous, and deeper** than previously thought, thanks to the **persistent action of continental glaciers** that transport vast amounts of **sedimentary material** to the seafloor.
According to **Amblàs**, a professor in the **Department of Earth and Ocean Dynamics at the [University of Barcelona](https://web.ub.edu/es/)**, the formation of these canyons is mainly due to **turbidity currents**, that is, **dense flows of sediment-laden water** that descend forcefully down steep slopes.
**Antarctica**, with its unique combination of **steep relief and glacial deposits**, favors the development of **massive structures**, even more imposing than those found in other regions of the planet.
## Regional differences in Antarctic submarine relief
The study is based on the second version of the **International Bathymetric Chart of the Southern Ocean (IBCSO)**, the most precise map to date of the **Antarctic seafloor**. Using a semi-automated methodology developed by the team, **15 morphometric parameters** were analyzed to identify **different typologies** among the canyons located in the eastern and western sectors of the continent.
As explained by **Arosio**, this is the first time that **significant regional differences** have been documented: canyons on the **eastern side** exhibit **U-shaped branching forms**, associated with **long histories of glacial activity and prolonged sedimentation**, while those in the **western sector** are **steeper, shorter, and V-shaped**, suggesting a different and possibly more recent geological dynamics.
For **Amblàs**, these variations reflect an **earlier and more persistent formation of the eastern ice cap**, a hypothesis that until now was only supported by sedimentary records but finds new evidence through **large-scale underwater geographic recognition**.
## The role of Antarctic submarine canyons in thermal exchange and global circulation
**Antarctic submarine canyons** play a key role in **planetary climate regulation**, by facilitating the **exchange of water masses between the continental shelf and the ocean depths**.
On one hand, they channel **Antarctic Bottom Water (AABW)**—cold and dense—towards the deep layers, fueling the **thermohaline circulation** that redistributes heat worldwide.
On the other hand, they allow **warmer currents**, such as the **Circumpolar Deep Water (CDW)**, to flow under the ice shelves, accelerating their **melting** and contributing to **sea level rise**.
However, **current climate models**—even those used by the **IPCC**—do not adequately integrate these processes.
“The dynamics that generate these canyons, such as vertical mixing of waters or localized channeling of currents, exceed the resolution of existing global models,” warns Arosio. This deficiency represents a **critical limitation in accurately predicting** the behavior of the **Southern Ocean** in the face of global warming.
## More exploration and better models: pending challenges
Given this scenario, scientists emphasize the need to **expand detailed bathymetry** in unexplored areas, where there may be **unknown formations** with significant effects on the oceanic and climatic system.
They also propose a greater **integration of observational data**, both **in situ and satellite**, and the improvement of **numerical models** to incorporate the **local physical variables** that operate in these submarine valleys.
“Without a faithful representation of these mechanisms, projections about the future of climate and sea level will remain uncertain,” conclude Amblàs and Arosio. Their work not only redefines the **map of the Southern Ocean**, but also raises a crucial question: **how many more secrets do the Antarctic depths hold**, and how could they transform our understanding of the planet?.
