Modeling the High-Frequency Component of Arctic Sea Ice Drift and Deformation

Abstract

Abstract Buoy observations of sea ice drift show that sea ice motion and deformation contain substantial high-frequency variability at subdaily timescales. However, numerical simulations of the sea ice dynamics normally do not include processes on such short timescales. Instead, by applying traditional water-drag formulations for the ocean–sea ice boundary layer, the inertial frequencies tend to be omitted in the spectra of modeled sea ice motion and deformation due to fictitious ocean damping. Here a dynamic–thermodynamic sea ice model is presented that includes “inertial embedding” of the sea ice into the oceanic boundary layer to reproduce sea ice motion and deformation not only at daily and lower frequencies but also at subdaily frequencies up to 2 cycles per day and higher. Comparison with buoy data shows that the embedded model much more successfully simulates the observed sea ice motion in regard to the high-frequency component. The results demonstrate that both inertial embedding of the sea ice–oc...