The little-explored region in northern Greenland was the last area of investigation that the Polarstern explored on three Arctic expeditions since the end of May 2025. In this largely unexplored sea area, a research team led by physical oceanographer Torsten Kanzow from the Alfred Wegener Institute was able to collect unique data on ocean circulation north and northeast of Greenland. In addition, a chain of six anchors was deployed there to carry out autonomous measurements for a whole year.
“We lack a fundamental understanding of the Arctic-wide circulation north and northeast of Greenland, where warm water is driving the melting of large glaciers. For example, it was not previously known whether there is a marginal current north of Greenland and in which direction it flows,” says Prof. Dr Torsten Kanzow, explaining why the region is of particular interest. The head of Physical Oceanography at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) adds: ‘Until now, there has been no structured oceanographic recording of the current conditions and the ecosystem in this region, which is covered by sea ice all year round. So we have broken new ground with this expedition and hope to be able to fill important gaps in our knowledge with the analyses.’
The measurements taken by the 50 scientific participants in the expedition were aimed at measuring the circulation of Arctic Atlantic water and polar surface water on the shelf and on the continental slope north of Greenland. The team also wanted to determine their connection to the East Greenland Current further south. At the same time, the connection between the current and stratification conditions and the marine ecosystems was investigated by sampling the distribution and relationships of nutrients, algae and zooplankton. Another important aspect of the measurement programme was to find out how the ocean-driven melting of retreating glaciers is influenced by Atlantic water and how glacier meltwater affects coastal circulation and the export of carbon to the open ocean.
‘Our measurement programmes were extremely successful. Initial results show that along the shelf edge north and northeast of Greenland, there is a current band at depths of a few hundred metres that transports warm Atlantic water from the Arctic Ocean southwards,’ reports the scientific leader of the expedition. There were initial indications that this water had travelled different paths in the Arctic Ocean before reaching the north Greenland coast.
Torsten Kanzow explains further: “In the area of ocean currents at the sea surface that transport cold and fairly fresh polar water masses, the picture was more complex: in the southern part of the measurement area, we found pronounced currents directed southwards (i.e. towards the Fram Strait), as expected. In the northern part, however, we found currents in the opposite direction (i.e. towards the Nares Strait between Greenland and the Canadian Archipelago). Subsequent analyses will provide information about the cause of this current and whether it is part of a current band that transports polar water masses west of Greenland out of the Arctic Ocean. These initial findings have helped us to deploy anchored continuous measurements, which we hope to recover next summer and which will then enable us to assess whether the initial findings from this voyage also apply over a whole
year.”
Announcement by the AWI Bremerhaven