A coupled ice-ocean modeling study of the northwest Atlantic Ocean

[1] A coupled ice-ocean modeling system is developed for the northwest Atlantic Ocean based on the second version of the Los Alamos sea ice model and a regional ocean circulation model. The coupled ice-ocean system differs from other coupled systems for the same region mainly in two ways. First, the semi-prognostic method suggested by Sheng et al. [ 2001] is used in the ocean component. This method adjusts the momentum equation of the ocean component to reduce drift of the modeled ocean state, allowing us to carry out a multiyear simulation. Second, the sea ice component uses the elastic-viscous-plastic ice rheology developed by Hunke and Dukowicz [1997] and Winton's [2000] three-layer thermodynamics. The coupled system is forced by climatological monthly mean atmospheric forcing at the atmosphere/ocean, atmosphere/ice interface, and oceanic forcing at the model open boundaries. The system is integrated for 3 years. Model results from the third year compare favorably with the observations in the region. The coupled system reproduces reasonably well the phase and magnitude of the annual cycle of sea ice. We demonstrate the effect of the ice heat capacity, previously unaccounted for in earlier model results of this region, in delaying the springtime sea-ice melt on the Labrador and Newfoundland Shelves.