The interaction of thermally excited gravity waves with mean flows

It is shown that the thermal excitation of internal gravity waves in a semi‐infinite atmosphere will lead to mean accelerations of the fluid within the region of excitation. While accelerations both in the direction of and opposite to the wave's phase speed are produced, the mean density weighted acceleration is opposite to the phase speed's direction. The mechanism involved is studied for a wide variety of cases, and explicitly applied to the examination of the mean flows resulting from thermal tides on Venus and the Earth. The procedure for studying the nonlinear evolution of flows is developed for cases with and without damping, and the results are applied to a discussion of the evolution of the observed 4‐day circulation on Venus.

Notes

Alfred P. Sloan Foundation Fellow.