Stratified flow over sills.

Abstract

A feature of many coastal waters is the presence of topographic irregularities, such as ridges, banks or sills, that inhibit or at least modify the movement of water past them. An important example occurs in the flow over sills in fjords; here the water is often strongly stratified due to river discharge, it may have a net shear due to gravitational circulation and the flow will be time dependent due to meteorological and tidal forcing. The topic is reviewed for the viewpoint of fjord oceanography, but the problem is much more general than this and has its origins in atmospheric studies such as airflow over mountains, as well as in certain aspects of classical hydraulics. (from paper)