An Unfiltered Primitive-Equation Model of the Upper Layers of the Pacific Ocean.
A resumption of work begun by Crowley to construct a model of stratified ocean circulations based on the unfiltered (or free-surface) primitive equations of motion. Solutions for temperature and velocity are sought to an initial value problem using an explicit, leapfrog, numerical scheme. This introduces the problem of initialization of unfiltered primitive equations for oceanic predictions, which represents a novel feature of the present study. Representative results from initialization and a 15-day prediction using climatological January initial and boundary data are presented. Specification of geostrophic and nondivergent initial data for prescribed temperature, followed by spin-up after the method of Sarkisyan, is found adequate to initialize the model without introducing unrealistic gravity-inertial oscillations. Use of a fixed value of bottom friction is effective in damping transients generated by the initial data. Spin-up is achieved in less than 90 simulated days, after which thermal imbalances generally exist. 84 pp. Ref.