A coupled ice-ocean model in the pan Arctic and North Atlantic Ocean: simulations of seasonal cycle

A coupled ice-ocean model (CIOM) is configured for the pan Arctic and North Atlantic Ocean (PANAO) with a 27.5km resolution. The model is driven by the monthly atmospheric climatology averaged from the 40-year NCEP reanalysis (1958-1997). The ocean model is the Princeton Ocean Model (POM), while the sea ice model is based on a full thermodyanical and dynamical model with plastic-viscous rheology. A sea ice model with multi-category in sea ice thickness is utilized. We first focus on seasonal cycles of sea ice and ocean circulation. This model reasonably reproduces seasonal cycles of both sea ice and ocean. Climatological sea ice areas derived from historical data are used to validate the ice model performance. The simulated sea ice cover reaches a maximum of 14 x10 km in winter and a minimum of 6.7 x10 km in summer, which are close to the 95-year climatology with a maximum of 13.3 x10 km in winter and a minimum of 7 x10 km in summer. The simulated general circulation in the Arctic Ocean, the GIN s eas, and northern North Atlantic Ocean are qualitatively consistent with historical mapping. We found that the winter low salinity or freshwater content in Canada Basin tends to converge due to the strong anticyclonic atmospheric circulation that drives the anticyclonic ocean surface current, while summer low salinity or freshwater tends to spread inside the Arctic and exports out of the Arctic, due to the relaxing wind field. We also found that the warm, the saline Atlantic Water intrudes farther into the Arctic in winter than summer due to prevailing winter wind stress over the northern North Atlantic that is controlled by the Icelandic Low. Seasonal cycles of temperature and salinity at several selected representative locations reveals regional features that characterize different water mass properties.