Background
Warm Atlantic Water flows northward in the eastern Nordic Seas toward the Arctic Ocean. Along this pathway atmospheric cooling leads to water mass transformation. The Atlantic Water then leaves the surface in Fram Strait between Greenland and Svalbard in a region where the horizontal density gradient at the surface is large. The properties that are set in Fram Strait affect both the mid-depth interior Arctic Ocean and the overflow water forming North Atlantic Deep Water. We have deployed three moorings in a triangle in Fram Strait to resolve submesoscale gradients in this last region of water mass transformation of the Atlantic Water. Here we advertise a Postdoc position at AWI that will analyze this unique mooring data set. A particular focus will be on quantifying the temporal variability from hours to seasons of submesoscale gradients in the surface mixed layer in Fram Strait. Dynamical analyses will reveal the processes participating in the transformation of Atlantic Water. You may participate in shipboard work in Denmark Strait and Fram Strait in 2026 (mooring deployment and recovery). Historical data from those areas may also be analyzed to better quantify the background conditions in which the novel submesoscale resolving observations are embedded. You’ll be part of the DFG-AEI collaborative project MIXSED; more details on the position can be found here http://www.mixsed.uni-hamburg.de/news.html.
Your Tasks
Performing research to achieve the goals of the MIXSED project Participation in research cruise(s) and data acquisition at sea Processing, documenting, and analysing oceanographic data Collaborating with project partners to interpret physical oceanographic data, especially a Postdoc at the University of Hamburg who will perform similar analyses using data from the bottom mixed layer near Denmark Strait Leading the publication and presentation of the research results
Your Profile
PhD in physical oceanography, climate physics, or a related discipline Strong background in physics, especially (geophysical) fluid dynamics Strong programming skills in e.g. Matlab or Python Experience with (ship-based) field work and analysis of simulated or sensor-derived data is an asset Very good spoken and written English (approximately equivalent to CEFR level C1)
We offer
Access to state-of-the-art observational data sets in the polar regions which combine process-oriented observations with long-term observations maintained since 1997 Supervision during the analysis of the data and the publication and dissemination of the results At-sea supervision in how such observational campaigns to the polar regions are implemented with the aim for the Postdoc to be group leader in at least one polar expedition A large network of collaborators both within AWI and across the MIXSED project Support in career development
More details:
One of the source regions of North Atlantic Deep Water is the Nordic Seas. Water flows northward in the Norwegian Atlantic Slope and Front Currents and gets cooled and densified by strong atmospheric heat loss. This water then leaves the surface in Fram Strait between Greenland and Svalbard in a region where the horizontal density gradient at the surface is large. The water then flows southward and eventually crosses the Denmark Strait upon which it descends along the seafloor as a gravity plume. Along this pathway the water is subject to water mass transformation associated with submesoscale instabilities: In Fram Strait those submesoscale instabilities take place in the surface mixed layer and south of Denmark Strait those submesoscale instabilities take place in the bottom mixed layer, where the strong flow also affects sedimentation. A collaborative project funded by the German Deutsche Forschungsgemeinschaft (DFG) and the Spanish Agencia Estatal de Investigación (AEI) called Mixsed (“Mixing and Sediment Dynamics”) aims to understand this water mass transformation. The Alfred Wegener Institute (AWI) (PI Wilken-Jon von Appen) has deployed a mooring array resolving submesoscale gradients in the surface mixed layer in the eastern Fram Strait in summer 2024 which will be recovered in summer 2026. The University of Hamburg (PI Eleanor Frajka-Williams) will deploy a mooring array resolving submesoscale gradients in the bottom mixed layer south of Denmark Strait for spring to fall 2026. Further shipboard activities in Denmark Strait will target associated sediment dynamics (PIs David Amblas, Anna Sànchez Vidal, Maria Dolores Pérez Hernández). Here (https://jobs.awi.de/Vacancies/2027/Description/2) we advertise a Postdoc position within MixSed work package 1 (http://www.mixsed.uni-hamburg.de/research/workpackage-1.html) at AWI that will analyze the mooring data in Fram Strait. A particular focus will be on quantifying the temporal variability from hours to seasons of the submesoscale gradients in the surface mixed layer in Fram Strait. This will be used for dynamical analyses (for example the analyses might be similar to these studies: DOI:10.1175/JPO-D-18-0253.1, DOI:10.1175/JPO-D-21-0099.1, DOI:10.1175/JPO-D-15-0170.1) revealing processes participating in the water mass transformation. The Postdoc may participate in the shipboard work in Denmark Strait and Fram Strait in 2026 (mooring deployment and recovery). Historical data from those areas may also be analyzed to better quantify the background conditions that the novel submesoscale resolving observations are embedded in. The Postdoc will closely collaborate with the PIs and with a Postdoc at the University of Hamburg who will perform similar analyses using the data from the bottom mixed layer in Denmark Strait.