The Simulation of Vertical Diffusion for the Surface Release in the Convective Boundary Layer
对流边界层中地面源的铅直扩散模拟

It was found that the mode of maximum concentration descended for the elevated releases, bot lifted for the near-surface releases in the convective boundary layer (CBL). The mechanism which causes this oposite geometric figures is analysed. It is believed that either the diffusion of elevated releases or that of near surface releases can be simulated by a same random diffusion model, provided the characteristics of the vertical turbulence in the CBL can be simulated properly. Therefore, the model used to simulate the diffusion of elevated releases by authors before is used to the simulation of near-surface releases, and the satisfactory result is obtained as well. This confirms the effectiveness of the model further. The model is examined by the Thomson's criteria. The theoretical reasonableness and the application limits of the model is discussed.