The autonomous submarine (AUV) "Ran" was deployed on risky missions under the floating glaciers of Antarctica. During one of these missions, the seven-metre-long submersible, which can measure and document its surroundings in the water, was lost in January 2024.
"The data we obtained during the Ran expeditions is unique in the world and of great value for international research. At the same time, they are associated with high risks, and we knew that something like this could happen. Personally, I think this is a better ending than gathering dust in a garage," said Anna Wåhlin, polar researcher and professor at the University of Gothenburg, as the submarine disappeared under the Antarctic ice forever.
Gigantic "Doomsday" glacier
The Thwaites Glacier in Antarctica is gigantic and is sometimes referred to as the "Doomsday Glacier" because it has the potential to raise global sea levels by several metres if it were to melt completely. Ran's measurements have attracted a great deal of attention, and not just among polar researchers.
"This was the second time we took "Ran" to Thwaites Glacier to document the area under the ice. Thanks to our submarine, we were the first researchers in the world to enter the Thwaites Glacier in 2019, and during the last expedition we visited the same area again. Even though you can see the melting and movements in the ice from satellite data, this gives us close-up images of the underside of the ice and information about exactly what mechanisms are behind the melting," says Anna Wåhlin.
Thanks to a major donation from the Voice of the Ocean Foundation (VOTO) and funds from an insurance company, the University of Gothenburg will be able to purchase a new AUV, which is scheduled for delivery in the winter of 2026/2027. The new submarine, named "Ran II", will have the same capacity as its predecessor, but will be equipped with an optimised decision support system for emergencies and improved navigation. The improvements will increase both safety and precision in hard-to-reach environments such as under glaciers, under sea ice and near the seabed.
At the same time, the University of Gothenburg and Voice of the Ocean are entering into a close collaboration that will enable researchers to use "Ran II" for studies in nearby areas, such as the Baltic Sea. Through VOTO's Ocean Support initiative, researchers will have access to advanced marine technology, autonomous platforms and high-quality data, which will accelerate the development of modern marine research.
Submarine in the service of science
In 2019, Swedish researchers carried out the first measurements under the infamous Thwaites Glacier, also known as the "Doomsday" glacier, and detected, among other things, inflows of warmer, saline water into the glacier. The submersible also collected some of the highest-resolution data ever obtained from the Antarctic continental shelf, enabling studies of processes that were active when the ice retreated around 100 years ago. Using multibeam echosounders, the underside of the ice was mapped with high precision, and in 2022 "Ran" carried out the first complete mapping of the underside of a glacier, finding previously unknown structures. These indicate local and/or periodic melting processes deep under the ice, a breakthrough that has opened up a new interdisciplinary field of research.
