Parameterization Treatments of Vertical Exchange Model for Chemical Species in the troposphere
对流层物质垂直交换模式中的参数化处理

In order to study the contributions of the parameterization forms of the variation of vertical eddy diffusivity (Kz)with height in the troposphere (TL) to the vertical exchange of chemical species, comparative numerical simulation for 5 different Kz patterns is carried out with "high resolution mode! for species exchange within the troposphere" (EM3) and OSCAR 4. The results show that both high frequency turbulence influenced by the relative motion of the earth's surface in planetary boundary layer (PBL) and various shear turbulence derived from dynamical and thermodynamic processes in TL above PBL are better described by KKZ pattern; both vertical motion and Kz play an important role in transporting species from the lower PBL up to the upper TL and from the source level down to the bottom PBL; the vertical motion is intermittent in temporal and spatial distribution, but Kz is continuous in the whole TL. Kz can make greater contribution to vertical exchange of species than the mean vertical motion.