An unmanned submarine exploring the depths reported strange formations near the ice West Antarctica. The car has driven almost 16 kilometers Dotson platformwhere it disappeared from radar after mapping the area.
A study led by Professor Anna Wolin, an ocean physicist from the University of Gothenburg, made it possible to obtain detailed maps of the base of the ice mass. This data provides more evidence of melting leading to sea level rise.
Ran submarines contribute to new knowledge about Antarctic glaciers. Photo: Anna Wåhlin/University of Gothenburg.
Mission under the Antarctic seabed
The submarine, called Ran, operated autonomously for several weeks, without real-time communication due to the inability to transmit signals through hundreds of meters of ice cover. In the campaign held in 2022, the car remained 27 days in operation and managed to go about 18 kilometers into a hidden cavity under the platform.
The submarine used an advanced multi-beam sonar system to image the underside of the ice. Photo: Anna Wåhlin/Science Advances
The goal was to understand why the east side of Dotson melts more slowly, while the west side melts faster. According to the research team, “the work sought to explain the strong contrast between the eastern side, which is thicker and more stable, and the western side, which is thinner and more vulnerable.”
For this, a high-precision sonar was used, with the help of which it was possible to map more than 140 square kilometers of frozen basean area completely inaccessible until now.
Objects unknown to science
The collected data revealed a hidden landscape consisting of terraces, cavities and depressions with unusual shapes. The researchers identified step-like platforms, along with drop-shaped depressions up to 300 meters long, as well as channels and eroded surfaces, as well as smoother areas in areas where the currents are stronger.
An illustration of the processes described in the Dotson Ice Shelf article. Photo: Science Advances
These structures do not appear on satellite images, which explains why they have remained hidden. It was also found that warm ocean water known as Deep Circumpolar Currentplays a key role. This flow transports heat to the base of the ice and creates irregular weathering, concentrated especially on the western side.
Widening cracks
“The wound also recorded full-thickness fractures, many of which had widened and softened at their base as a result of melting,” the study detailed in Science Advances. In these narrow spaces, water circulates faster, which increases erosion and accelerates ice loss.
Another of the most important findings was the presence of faults that cross the entire platform. These cracks, some of which have been visible since the 1990s, show signs of having widened as a result of contact with warmer water.
Scientists warn that these channels act as pathways that concentrate heat at specific points, a phenomenon that current climate models cannot accurately capture.
Disappears into the depths
After completing several successful missions, the submarine was sent again to expand the maps obtained. However, on this last expedition, the team finally lost contact.
“Seeing Ran disappear into the dark and go on her mission for over 24 hours without contact is disturbing,” Anna Wolin said. The vehicle did not arrive at the collection point, and efforts to locate it were unsuccessful.
The reasons for his disappearance have not been confirmed. The researchers believe that technical failures or a collision with ice structures are possible, although there is no conclusive evidence.
