A NOTE ON OVERSTABILITY AND THE ELASTOID-INERTIA OSCILLATIONS OF KELVIN, SOLBERG, AND BJERKNES

Abstract

Results elucidating the mechanism by which overstable (oscillating) cellular convection occurs in rotating layers are given. There is a close connection with the elastoid-inertia oscillations in a rotating cylinder discussed by Kelvin, Solberg, and Bjerknes, and it is found that diffusion of heat by conduction acts in a deslabilizing way in the motion. Simple experiments in a rotating cylinder on the elastoid-inertia oscillations show a remarkably close agreement with the free periods calculated theoretically. This, in the field of meteorological experiments, is important in establishing close agreement with meteorological theory in a situation where the flow can be strongly ageostrophic.