Séminaire
We have developed an atmospheric general circulation model (AGCM) for Venus on the basis of AFES (AGCM For the Earth Simulator) and performed a very high-resolution simulation. The highest model resolution is T159L120; 0.75 degree times 0.75 degree latitude and longitude grids with 120 vertical layers (Δz is about 1 km). In the model, the atmosphere is dry and forced by the solar heating with the diurnal change. Newtonian cooling that relaxes the temperature to the zonally uniform basic temperature which has a virtual static stability of Venus with almost neutral layers. At the initial state, fast zonal wind in a solid-body rotation is given. In this seminar, I will report several results newly obtained by this model. 1. Baroclinic instability; which appears in the cloud layer with small static stability and large vertical shear of the zonal flow. 2. Polar vortex; self-consistently generated by barotropic instability whose horizontal and vertical structure is consistent with the previous observations. 3. Kinetic energy spectra; which decreases by -5/3 power law in a range from wavenumber 4 to 45, whose range is different from that on Earth.
MP Lefebvre (0144272799)