This paper describes a simple model for predicting compactness over a given area. The model incorporates equations of continuity and momentum. The momentum equation is based on a balance between air-ice stress, water–ice stress, Coriolis force, and internal ice resistance. Since our interest is in short-range small-scale prediction, as a first step we have neglected sources and sinks terms in the continuity equation and assumed ice to be a film of Newtonian highly-viscous fluid. The solution of a simple equilibrium formulation is used as initial conditions.
Surface winds over the area of interest are obtained from an available model developed on the basis of similarity theory. The compactness model has been applied for a few real cases in summer 1975 over the Beaufort Sea area. The preliminary results of the model are encouraging. The main advantage of this model is that it can run on mini-computers available at most forecasting centres.