Chapter 6 Experimental Reality of Geostrophic Adjustment

Abstract

Publisher Summary This chapter describes experimental reality of geostrophic adjustment. The rotating shallow water model (RSW) is probably the most pedagogical and useful model to understand geophysical fluid dynamics. The main purpose is to understand which dynamical processes are filtered out by the RSW model while they occur sometimes in real experiment. Even if the RSW equations are based on drastic assumptions (hydrostatic balance, quasibidimensionality, and weak dissipation), it is a surprisingly good model of many phenomena in the atmosphere and the ocean. The rapidity of the geostrophic adjustment does not depend on the size or the amplitude of the initial unbalance state. Therefore, the existence of a mean adjusted state does not depend on the presence of fast wave motion. However, the inertia–gravity waves detected in the experiment have a dispersive behavior because of the finite value of the aspect ratio parameter α.