Modelling the generation of gravity waves by a maritime continent thunderstorm

Observed wind and temperature profiles are used to initialize a model calculation of a maritime continent thunderstorm, and the numerical solution is used to explore the effect of tropospheric shear on the gravity-wave generation. The resultant convective system is qualitatively similar to that observed. The modelled gravity waves propagate away from the cloud with wave-fronts that are approximately circular, implying that the convective clouds do not generate waves which propagate in a preferred direction. The gravity-wave generation is related to the oscillation of the convective updraughts about their level of neutral buoyancy. While the general features of the gravity waves are similar in most respects to a previous study which used an idealized wind profile, the frequency of the gravity waves is Doppler-shifted by the tropospheric wind shear. The result is a much broader power spectrum in comparison to the idealized cases.