| Summary: | A simple box model of a a high-latitude two-layer ocean, first developed by Martinson et al., 1981, is applied to four Arctic regions connected together: the Greenland Sea, the Norwegian Sea, the Arctic Ocean, and the Greenland Gyre. The latter, in fact, is a small convective region embedded in the northwest corner of the Norwegian Sea region. The model for each region consists of a thermodynamic ice layer that covers two layers of salty water which can, under specific conditions, become statically unstable and hence create a state of active overturning. The system is forced by monthly mean atmospheric temperatures in the four regions, as well as by continental runoffs and by inflows from adjacent oceans. The model predicts the ice thickness, and the temperature and salinity of the water in the upper layer for the four regions. Also determined are the water temperature and salinity for the lower layer in the Arctic Ocean box. The convective state of any given region, i.e., whether it is in an active overturning mode or not, is also obtained continuously. The different output variables of the model, which are the response to climatological forcing conditions, compare favourably with observed data. In this control run, the Arctic Ocean region is characterized by continuous ice cover only during winter, and the Norwegian Sea region never forms an ice cover. Another feature of the model is the winter time occurrence of convective overturning in the upper 200 m in the Greenland Gyre region. (Abstract shortened by UMI.)
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