Convectively generated gravity waves simulated by NAM-SCA

Abstract

Convectively generated gravity waves are an unresolved process in global models. However, parameterization of their effects is difficult because the parameterized wave spectrum must be linked to the convective source, which is itself parameterized. Here we use the NAM-SCA model (nonhydrostatic anelastic model with segmentally constant approximation), which is midway between a cloud-resolving model and convection parameterization. Unlike conventional convection parameterizations, NAM-SCA is built directly upon a nonhydrostatic anelastic model, and thus it describes dynamical processes consistently but in a “compressed” manner (i.e., with truncation via a spatiotemporal adaptive mesh) that fac..