A Numerical Experiment on the Lee Cyclogenesis of Qinghai–Xizang Plateau in a Six–level Limited Area Model

The present model, including more physical processes, is a six-level primitive equation model for Asia area with efficient and accurate numerical techniques for the computations of pressure gradient force and the initial fields in the vicinity of mountains in σ–coordinate. The numerical experiments on the cyclogenesis of Qinghai-Xizang Plateau are performed successfully by using the present model with the initial condition based on objective analysis data on 11th July, 1981. More interesting simulation results are displayed, and they show that the dynamic influence of Qinghai-Xizang Plateau is an important role to the lee cyclogenesis with low-level south–westerly jet stream in southwestern China. The results also that unless the consideration of mountain effects (or reducing the orographic height by the factor of 0.5 in the model) the simulations are failure