Abstract
The convective source and momentum flux spectra of a parameterization of convective gravity wave drag (GWDC) are validated in a three-dimensional spectral space using mesoscale numerical simulations for various ideal and real convective storms. From this, two important free parameters included in the GWDC parameterization—the moving speed of the convective source and the wave propagation direction—are determined. In the numerical simulations, the convective source spectrum shows nearly isotropic features in terms of magnitude, and its primary peak in any azimuthal direction occurs at a phase speed that equals the moving speed of the convective source in the same direction. It is found that the moving speed of the convective source is closely correlated with the basic-state wind averaged below 700 hPa (