Laboratory studies of orographic effects in rotating and stratified flows

This article reviews some aspects of the roles that laboratory experiments have played in the study of orographic effects in the Earth's atmosphere an d oceans. The review focuses on, but is not restricted to, physical systems for which the effects of both background stratification and rotation are i mportant. In the past, such laboratory studies have been largely decoupled from attempts to make quantitative comparisons with the results of numerica l-model studies or observations from field programs. Rather, they have been used mostly in the important task of better understanding the physics of r otating and stratified flows. Furthermore, most laboratory experiments conc erned with the effects of orography on either homogeneous or stratified rot ating fluids have considered laminar flows, whereas their counterpart flows in the atmosphere and ocean are turbulent. We argue that laboratory invest igations are likely to be more useful in addressing critical environmental problems if the studies are more closely allied with numerical-modeling eff orts. The latter, in turn, should be tied to field projects, with the overa ll objective of improving our ability to predict the behavior of natural sy stems. In this same spirit, we conclude that far more attention should be g iven to the laboratory simulation of the turbulent characteristics of natur al flows. The availability of rapidly developing technology to acquire and analyze laboratory data provides the capability necessary to support the in creasingly important roles that laboratory experiments can play in understa nding and predicting the behavior of our natural environment.