ИСТИНА

Complex shorelines and coastal relief influence strongly on the wind speed. Since the Arctic is poorly covered by ground observations, one of the most reasonable approaches to investigate these events is hydrodynamical high-resolution modeling. In this work we are applying the COSMO-CLM model to reproduce wind field and characteristics in different rugged shore conditions. Some model experiments designed with the regional climate non-hydrostatic atmospheric model COSMO-CLM investigated the best configuration to reproduce mesoscale circulations in the Arctic coastal zones considering different relief conditions for example of the Kara Sea. Some mid-term experiments of three months timespan – Aug-Oct 2012 and Jul-Sep 2014 – were conducted over the Arctic domain and specially over the Kara Sea region using the downscaling approach with ~12 and ~3 km horizontal grids. Considering periods were characterized by some storm events. The focus of these experiments was to reproduce surface wind and wave characteristics in the best way, especially near the shorelines during storm events. Verification of different experiments showed the best configuration of COSMO-CLM with the “spectral nudging” technique and reducing the model time step. However, verification and detailed investigation of model runs raise a question about the quality of this verification, and how relevant are wind station data in different coastline and relief conditions. Therefore, an additional analysis carried out from synoptic overview to influence of coastline configuration on different mesoscales and for different regions. Malye Karmakuly (Novaya Zemlya island), Belyi and Dikson islands were considered as different examples to study wind and waves regime. Although the model could not describe all-scales dynamics using ~3 km resolution, it could simulate islands’ wind shadows, tip jets, downslope winds, vortex chains, etc. of different scales realistically. It justifies the further research could apply the finer resolution to learn detailed properties of mesoscale circulations and extreme winds. This analysis has shown a need to investigate these circulations using numerical modelling to predict it better.