A 2-dimensional advection-diffusion ocean model with anisotropic diffusion
Charles A. Lin · Geophysical & Astrophysical Fluid Dynamics · 1990
A 2-dimensional steady state latitude/depth advective-diffusive ocean model is formulated. The advecting flow is an idealized thermohaline circulation with upwelling at the low latitudes and downwelling at the high latitudes. Diffusion may occur along geopotential co-ordinates, or along isopycnal surfaces with a constant slope. The latter introduces an anistropy in the governing advection-diffusion equation for a passive tracer. The model is forced at the top with a specified tracer distribution. The sides and bottom are insulating. The equation is scaled to yield two non-dimensional parameters: the Peclet number(Pe), and an isopycnal slope parameter(γ). General results are derived analytically for the diffusive limit(Pe→0). A parameter study is carried out using numerical integration for the non-diffusive cases(Pe≠0). The results are interpreted in terms of the diffusive and advective fluxes, and the homogenization properties of the tracer field.