On Big Waves Under Polar Lows Based on Altimeter Measurements and Model Simulations

Results of investigations of surface waves generated by Polar Lows (PLs) in the Barents and Norwegian seas are presented. A parametric wave model originally developed in [1] is applied to reproduce surface waves in Arctic seas generated under non-stationary and non-uniform wind field of PLs, observed by altimeters. The ERA-5 wind field reanalysis is used as the input parameter. The solution of model equations provides hourly fields of wave parameters (significant wave height, SWH, mean wavelength, and mean direction) on the regular grid. Satellite altimeter observations and analysis of model simulations reveal appearance of abnormal high surface waves, resulting from the group velocity resonance between developing waves and moving wind field. This resonance effect (or effect of wave trapping) occurs when the zone of strong wind inside the PL is located in the right sector, where the direction of the wind velocity coincides with PL heading.