Thermal Effects of the Tibetan Plateau on Rossby Waves from the Diabatic Quasi-Geostrophic Equations of Motion

From the diabatic quasi-geostrophic equations of motion, the authors analyze the characteristics ofdiabatic Rossby waves including the thermal effects of the Tibetan Plateau. When the basic zonal flow isbarotropic, it is demonstrated that the cooling of the Tibetan Plateau in winter not only facilitates themeridional propagation of Rossby waves but is an important driving mechanism of the intraseasonaloscillations in middle and high latitudes. When the basic zonal flow is baroclinic, it is found that the coolingof the Tibetan Plateau in winter facilitates the instability of Rossby waves, while in summer there is athreshold for the influence of the heating of the Tibetan Plateau on the stability of Rossby waves.