The scientific work in SUPERFLOW is divided into 3 work packages, related to i) observations, ii) high-resolution, realistic numerical simulations, and iii) idealised modelling.
i) I processed and quality-controlled observations of hydrography and ocean currents from moorings that had been deployed northeast of Iceland and in the northwestern Iceland Sea. Together with shipboard hydrographic observations from this area, we investigated where dense water that supplies the lower limb of the AMOC may be formed in the Iceland Sea, what role air-sea interaction plays in determining the density of newly formed water, and by what pathways this dense water is transported toward the Greenland-Scotland Ridge.
ii) I evaluated a high-resolution, realistic numerical simulation for the Nordic Seas against the available moored hydrographic and velocity time series and historical hydrographic observations. Furthermore, we conducted experiments with synthetic floats by releasing particles and following their trajectories to study the upstream and downstream pathways of the dense-water currents north of Iceland in the numerical simulation. From the assessment of the numerical simulation, we concluded that the model does not seem suitable to determine the pathways and volume transports of the deep currents on the slope north of Iceland. However, as surface currents have previously been shown to be represented well in this model, I now co-supervise one PhD and one MSc student who use this simulation to investigate the surface-intensified East Greenland Current in the western Nordic Seas.
iii) To understand the dynamics of dense-water currents north of Iceland, we used a simple, 2-layer idealised model and investigated the formation of dense slope currents and their flow around an island. The island is connected to submarine ridges on its eastern and western side. In our set-up, we introduced a source of dense water in the north of the domain that supplies the deep layer. This results in transport of dense water around the island in the south of the domain and across the submarine ridges. In particular, we are interested in the role of eddies in transporting the dense water toward the slope and forming the boundary currents, and how the deep currents partition to cross the eastern and western ridge.
So far, I have (co-)authored four publications that are related to the project (two additional manuscripts are currently under review). I have presented my work at 10 international conferences and workshops. In particular, the annual Arctic-Subarctic Ocean Fluxes workshop provided an excellent platform for establishing and continuing scientific collaborations in the community for regional, process-oriented studies in the subpolar regions.
For the outreach component of the project, we published our findings in a scientific journal for kids and teenagers. This paper, which had been reviewed by teenagers, formed the basis for a classroom lesson with a DIY-experiment we developed for high-school students. The material for the lesson has been published online and was presented at a teacher’s conference.
