Stationary and Slowly Propagating Waves in a Venus-Like AGCM: Roles of Topography in Venus' Atmospheric Dynamics

Topography and solar heating are incorporated in our Venus-like AGCM. Superrotation is fully developed at the cloud top. Stationary waves and slowly propagating waves with phase velocities of about 0 m/s are predominant because of the topographic and thermal forcings. The topography leads to the north-south asymmetries of the angular momentum and the vertical EP flux in the lower atmosphere. Since the winds near the surface are weak and the static stability is low, the vertical eddy momentum flux of stationary mountain wave with phase velocity of 0 m/s is not large near Maxwell Montes at high latitude. Rather than the stationary wave, slowly propagating waves produce large vertical EP flux. In the equatorial region where Aphrodite Terra is located, the vertical eddy momentum flux of stationary wave is locally predominant near the surface.