Numerical Simulation of the formation and development of Vortices over the Qinghai-Xizang Plateau in Summer
Chen Bomin; Qian Zhengan and Zhang Lisheng(Lanzhou Institute of Plateau Atmospheric Physics, Chinese Academy of Sciences, Lanzhou 730000)
Ten schemes were designed by decreasing the Qinghai-Xizang Plateau terrain elevation,removing the sensible and latent heating on the surface and the latent heating in the air column, reducing the temperature lapse rate, enhancing the baroclinicity of the air column and canceling the fricnon at the surface and lateral the friction within the boundary layer. Then by using a limited -regionalnumerical model suitable for complex terrain regions and utilizing theFGGE level IIIb data, a set of 24 hour or 48 hour simulations were Performed for three typical vortexcases including the genesis and / or development stages in the summer of 1979. Finally, a conceptualmodel for the formation and development of the Qinghai-Xizang Plateau vortex was presented. Thevortex may be regarded as a local low pressure which strongly depends on the Qinghai-Xizang Plateauterrain and is dominated by stratification stability, the surface heating fluxes and latent heating in theair column.