A layered model of the study circulation in the South Pacific Ocean is constructed along the lines of Luyten, Pedlosky and Stommel, and driven by the mean annual wind stress distributions computed by Hellerman and Rosenatein. The results of the model agree quite well with published maps of topography of...
A simple parameterization of mixing processes originally developed by Kraus and Turner (1967) is included in a two-dimensional, two-layer theory of wind-driven coastal upwelling. Mixed-layer deepening is a competition between entrainment due to wind stirring, stabilization due to surface beating, and upwelling vertical velocity. For longshore winds favorable to upwelling,...
A theory of a two-dimensional wind-driven diabatic ocean mixed layer with strong horizontal gradients is formulated analytically. An equation that allows the relaxation of the strict Ekman balance—Coriolis force against wind stress—is derived from a careful consideration of the cross-gradient momentum balance. The relaxation scale depends implicitly on mixed-layer depth...
The materiality and neutrality of neutral density and several forms of orthobaric density are calculated and compared using a simple idealization of the warm-sphere water mass properties of the Atlantic Ocean. Materiality is the value of the material derivative, expressed as a quasi-vertical velocity, following the motion of each of...
An improved bound is obtained for the radius of the semicircle in the complex plane containing the complex phase speed of baroclinically unstable plane wave disturbances. In the limit of long waves, this bound contains a term increasing with β and decreasing with the mean stratification (i.e., decreasing with the...
The evolution of the covariance of two tracers involves a quantity called codissipation, proportional to the covariance of the gradients of the two tracers, and analogous to the dissipation of tracer variance. The evolution of the variance of a composite tracer—a linear combination of two simple, primary tracers—depends on the“composite...
A layered model of steady geostrophic ocean circulation driven by wind stress and buoyancy flux at the surface is derived. Potential vorticity, or thickness, of the two near-surface layers is driven by Ekman pumping and buoyancy pumping. The latter is represented as a flow of mass proportional to the modified...
The one-dimensional bulk mixed-layer model of Niiler (1975) is extended to two (or three) dimensions to take account of horizontal variation in wind stress on mixed-layer dynamics. Both surface stirring (Kraus and Turner, 1967) and bulk shear (Pollard et al., 1973) entrainment mechanisms are included. The development of horizontal structure...
The forms of the primitive equations of motion and continuity are obtained when an arbitrary thermodynamic state variable--restricted only to be vertically monotonic--is used as the vertical coordinate. Natural generalizations of the Montgomery and Exner functions suggest themselves. For a multicomponent fluid like seawater the dependence of the coordinate on...
The thermobaric nonlinearity in the equation of state for seawater density—namely, the dependence of thermal expansibility on pressure—coupled with spatial variation of the oceanic temperature–salinity (θ–s) relation generates a nonlinear behavior in the buoyant force that can counter the linear dispersion of baroclinic Rossby waves and produce solitary waves. A...