KINETIC-ENERGY ANALYSIS OF AN EDDY RESOLVING, PRIMITIVE EQUATION MODEL OF THE NORTH-ATLANTIC

As part of the World Ocean Circulation Experiment community modelling effort, a realistic primitive equation model of the North Atlantic Ocean has been implemented with a resolution high enough to allow the generation of eddies. In the present paper, the kinetic energy of the model ocean circulation is analyzed. The eddy kinetic energy distribution in the model shows a good agreement with data in the western Atlantic but a deficit in the eastern Atlantic, especially at periods of about 100 days. Kinetic energy balances are computed to allow comparison between the primitive equation model and previous quasi-geostrophic eddy resolving models. Essential instability mechanisms are present in both cases, but they are not efficient enough in the primitive equation model, which is too viscous and lacks the inertial character of quasi-geostrophic solutions. Our study therefore emphasizes the need for even higher resolution models.