10:15 AM - 10:30 AM
[PCG21-12] Small-scale disturbances reproduced by AFES for Venus
(Atmospheric general circulation model For the Earth Simulator)
Keywords:Venus, GCM, Waves
Starting from this idealized superrotation, the model atmosphere reaches a quasi-equilibrium state within 1 Earth year. This state is stably maintained for more than 10 Earth years. The zonal-mean zonal flow with weak midlatitude jets has almost constant velocity of 120 m/s in latitudes between 45°S and 45°N at the cloud top levels, which agrees very well with observations. We have investigated small-scale disturbances reproduced in the model. In the cloud layer, baroclinic waves develop continuously at midlatitudes and generate Rossby-type waves at the cloud top (Sugimoto et al., 2014b). At the polar region, warm polar vortex zonally surrounded by a cold latitude band (cold collar) appears successfully (Ando et al., 2016). As for horizontal kinetic energy spectra, divergent component is broadly (k > 10) larger than rotational component compared with that on Earth (Kashimura et al., in preparation). In the presentation, the relation between small-scale gravity waves and large-scale thermal tides will be also shown.