Vertically propagating atmospheric gravity waves (GWs) play a major role transporting energy and momentum throughout the atmosphere, which in turn has a significant impact on global scale flows, weather patterns, and climate. The resolution requirements of large scale numerical weather and climate simulations is such that it is impossible to directly model smaller scale GWs and their dissipation directly, and instead their impacts on the global flow must be introduced by a parameterization scheme. It is of particular interest, then, to study these smaller scale dynamics with the goal of improving their parameterization in larger scale models.

This study employes a finite-volume anelastic numerical model to simulate vertical GW propagation through an inversion in the mean temperature. The goal of this work is to quantify the impact of the inversion layer (IL) on the transmission and reflection of a variety of incident GWs. Two broad GW characteristics are considered. The first is wave amplitude. For waves of significant amplitude, wave instability, breaking and dissipation occurs at the IL hampering wave transmission. The second characteristic considered is the IL length scale. At linear amplitudes it is seen that for horizontal wavelengths smaller than the IL scale nearly the entire wave is ducted and reflected, while for larger horizontal scales there is a significant amount of transmission. This is true of both linear and nonlinear interactions and seems to partly ignore vertical wave scales. The wave's vertical scale also plays a role in GW transmission, though in a more indirect manner – through their influence on instability processes at the IL.

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*email: b.laughman@gats-inc.com
*Preference: Oral