ANALYSIS OF THE INTER-TRANSFOMATION OF EQUIVALENT BAROTROPIC AND BAROCLINIC ROSSBY WAVES

By using the low-spectral model simplified from quasi-geostrophic approximation two-level model,we obtained the result that the equivalent barotropic state is an equilibrium state of the atmosphere in that model,and discussed the conditions needed for existing the Rossby wave possessing the equivalent barotropic structure.And then we derived the oscillation equation reflecting the phase change of Rossby wave between higher and lower levels from the basic state of equivalent barotropic stationary Rossby wave,indicating the relations between the change of difference of phase at higher and lower levels and the disturbance of vertical shear,the amplitude disturbance of the part of waves of stream function and thermal wind stream function on the average level(A' and B').It is concluded that the inter-transformation exists between Rossby waves possessing the equivalent barotropic and baroclinic structure.