Mesospheric concentric gravity waves generated by multiple convective storms over the North American Great Plain

We employ convective plume and ray-trace models to simulate the GW-induced OH intensity perturbations from convective plumes, clusters and complexes. We find that the results using the background model wind (radiosonde/TIME-GCM) agree well with the late-time observations, when the images are dominated by southwestward, short-wavelength, high-frequency GWs. These late-time GWs propagate against the background wind, and have λh ∼ 30--40 km and periods of τ ∼ 20-30 min.

The OH intensity perturbations are enhanced because the vertical wavelengths λz increased, T '/ T ¯ increased, and the vertical velocity perturbations w' decreased (because the GWs were near their reflection levels). We also find that these short-wavelength GWs were created ∼5 h earlier by an extremely energetic, deep convective plume in South Dakota, thereby showing that small-scale, convective GWs directly link the troposphere and mesopause region.