Simulated Sensitivity of an August 2022 Arctic Cyclone–Sea-Ice Interaction Event to Various Sea-Ice and Ocean Configurations

The ability to resolve interactions between synoptic-scale Arctic cyclones (ACs) and sea ice in numerical models is hypothesized to be important for AC prediction. This hypothesis stems from the fact that lower-level winds and sea-ice morphology influence spatial distributions of sensible heat fluxes (SHFs), which play a key role in AC evolution. SHFs are dependent on sea-ice and ocean properties, so representing these properties accurately in numerical models is expected to be important for predicting AC evolution. Representing sea-ice and ocean properties accurately in numerical models is difficult, and the sensitivity of AC–sea-ice processes to sea-ice and ocean properties is uncertain.

An investigation of the sensitivity of AC–sea-ice processes and AC predictions to various sea-ice and ocean configurations in polar-modified Weather Research and Forecasting Model simulations during an AC–sea-ice interaction event is presented. The AC involved in the AC–sea-ice interaction event occurred during 15–27 August 2022. The AC featured an upper-level trough, a cold-core structure, fronts, and a low-level jet.

Downward SHFs, which reduce lower-level potential temperature, over sea ice were stronger in simulations using spatially varying sea-ice concentrations (SIC-based simulations) compared with simulations using binary sea-ice masks (mask-based simulations). As the AC moved over sea ice, AC intensity became weaker in SIC-based simulations than in mask-based simulations. As the AC intensity difference between SIC- and mask-based simulations emerged, lower-level vorticity generation due to vortex stretching near the AC center was weaker in SIC-based simulations than in mask-based simulations.