Model run with METROMS to evaluate open boundary conditions in CICE [idealized wind]

Support for time-varying open boundary conditions (OBC) have been developed for sea ice in the Los Alamos Sea Ice Model (CICE) by Pedro Duarte (NPI, Norway). This dataset is a result of using the coupled ocean (ROMS) and sea ice (CICE) modelling framework METROMS (https://github.com/metno/metroms) in order to test the effects of the above mentioned boundary conditions. The specific application of METROMS that was used was MET Norway's main forecasting system for the Barents Sea; the Barents-2.5km model; details about the model can be found at https://ocean.met.no/models.

The model was initialized from the TOPAZ4 model (Sakov et al., 2012) and was run for the period 2019.09.01 - 2019.09.20, one time without OBC and one time with OBC enabled using input data from TOPAZ4 at the boundaries. In both runs the model was set up realistically, but with the exception of idealized wind forcing. More specifically, the wind was blowing 10 m/s in the positive xi-direction until 2019-09.07 and then 10/m/s in the negative xi-direction for the rest of the simulation. The reasoning for this was to clearly demonstrate the effects of the OBC. Initially, the wind is blowing the ice away from the boundary and without using OBC for ice, it leaves open water in its path due to no information coming in through the boundary. With OBC enabled however, the simulation appear a lot more sensible with sea ice from TOPAZ4 coming in through the boundaries. When the wind switches to the opposite direction after 2019.09.07, on the case without OBC results in ice piling up at the boundary after some time. However, with OBC enabled, the ice exists the model domain.