A note on velocity fluctuations in drainage flows.

Abstract

This technical note discusses velocity fluctuations in drainage flows. Observations of such nocturnal flows have encountered surges or fluctuations in the downslope flow in a variety of locations. Many explanations for the phenomena have been offered, but the theory of compressional warming by Fleagle is most widely quoted. According to Fleagle, cooling accelerates the drainage flow, this producing an oscillation in the downslope flow. He developed a simple model of this process whose analytical solution exhibited this type of behaviour. It is the purpose of this note to make a simple extension of Fleagle's model in order to examine the impact of an external stratification on the ocillations. (A.B.)