This proposal is to continue investigation on topics of large scale circulation theory. With the aid of numerical and analytical models, Ierley has determined the effect of boundary conditions, western boundary layers and inertial jets on the vorticity balance of quasi-geostrophic (QG) ocean models. The main aspect of these studies is to comprehend the physical reasons for the features exhibited by the numerical solutions. Ierley has produced very valuable contributions to the theory of ocean circulation with his analysis of "q-driven" models, models in which the interior flow is determined by the advection and diffusion of potential vorticity. He will analyze very high resolution, low viscosity QG model solutions which show western boundary separation and intense inertial recirculation. This analysis is critical to interpret results of ocean models used for climatic studies.