The Dynamics of Oceanic Fronts. Part II: Shelf Water Structure Due to Freshwater Discharge

Abstract

Abstract In Part I of this series, a framework was introduced for the study of oceanic frontal dynamics. The dynamics was studied by posing an initial value problem, starting with a near-surface discharge of buoyant water with a prescribed density deficit into an ambient stationary fluid of uniform density. An essential aspect of the framework was the identification of the proper length scales: an inertial length scale L0, a buoyancy length scale h0 and a diffusive length scale hv. In Part I, the horizontal and vertical dimensions were scaled by L0 and h0, respectively; and two dimensionless parameters were formed, viz., Ro = L0/h0 and E = (hv/h0)2. It was shown in Part I that under this scaling, the normalized equations depended on E only for Ro sufficiently large. The solution for E small, i.e., for the almost inviscid case, was given in Part I; and the equilibrium state was discussed in a frame of reference in which the front was stationary. In this paper, we present the solution for large E. It will b...