About two weeks ago, a massive iceberg calved from the Antarctic Ice Sheet. As the only research vessel nearby, the Polarstern took the opportunity to enter the area between the iceberg and the Brunt Ice Shelf.
The first images from the seafloor show a great level of biodiversity in an area that was covered by thick ice for decades. The sediment samples gathered are expected to provide more detailed insights into the ecosystem, while a geochemical analysis of the water samples collected will allow conclusions to be drawn regarding the nutrient content and ocean currents.
The German research icebreaker Polarstern is the only research vessel on site, and penetrated the gap between the iceberg and the shelf edge, to explore the seafloor that has been covered by hundreds of metres of ice for decades. Experts from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) and their international partners arrived on scene shortly after the calving event.
Gale-force winds had initially kept the Polarstern from reaching the region, but on the weekend 13/14 March 2021, more favourable weather conditions led the captain to give a green light for making a circuit of the iceberg and exploring the surrounding area.
German Federal Research Minister Anja Karliczek underlined the importance of this mission, which is made possible through the institutional funding of the AWI by the Federal Ministry of Education and Research, as follows:
It is a unique opportunity offered to researchers on board Polarstern to explore the Antarctic Ice Sheet. I am grateful to the crew of the Polarstern for taking on the associated hardships and also risks. Polar research makes a decisive contribution to better understanding and foreseeing climate change and its consequences for our earth. We need this knowledge in order to be able to take effective countermeasures against climate change. The effects of climate change in Antarctica, among others, are worrying
To date, climate change has especially warmed West Antarctica; the global temperature rise hasn’t yet affected East Antarctica. However, climate models predict that, during this century, the air temperature will also rise over the East Antarctic Weddell Sea, negatively affecting the sea ice. In turn, such changes could produce fundamental transformations of the hydrography. The Antarctic is currently losing ice mass at a higher rate than before 2000, as the AWI experts have observed.
In order to create simulations, researchers need data from the regions in question. Accordingly, the Alfred Wegener Institute has conducted regular Polarstern expeditions to the Antarctic Weddell Sea since the 1980s. In this regard, the seafloor, ocean, ice and atmosphere are investigated, with different focus areas, depending on the respective expedition.
The experts found that, despite being permanently covered with ice for decades, the seafloor is home to impressive biodiversity. The deep-sea research team observed numerous organisms that had settled on stones of various sizes, surrounded by a silty landscape. The stones hail from the Antarctic continent and are transported to the ocean by glaciers.
The deep-sea team photographed and filmed this surprisingly species-rich ecosystem for the first time using the OFOBS (Ocean Floor Observation and Bathymetry System).
In the future, new technologies like autonomous underwater robots will be used to investigate such habitats.
