Convectively Coupled Equatorial Waves in a Global Storm-Resolving Model

We show how, in convection resolving configurations of the Icosahedral Non-hydrostatic Model (ICON), reducing the fall speeds of rain and ice leads to a stronger gravity wave group and a weaker moisture mode group of of Convectively Coupled Equatorial Waves (CCEWs). Reductions in these fall speeds upscale from the grid scale to the synoptic and planetary scales of CCEWs mediated by the frequency of different types of convection. Reducing the fall speeds leads to increases in the frequency of shallow and stratiform convection and to decreases in the frequency of deep convection. In turn, these changes in convection are reflected in the ability of the model to develop the tilt and top-heaviness of CCEWs, which ultimately leads to their better representation in ICON. Our findings suggest a representation of CCEWs within ICON that agrees with their observed multiscale structure and provides further support for the classification of CCEWs.