Abstract
Wind tunnel experiments are frequently carried out as a useful method for atmospheric environ-mental prediction.
Specially gas diffusion in the complex terrain and around ground structures entails the model experiment. This paper describes simulation of field meteorological condition in the wind tunnel and examples of diffusion phenomena clarified with use of flow and diffusion visualization. Meteorological factors reproduced are atmospheric stability and wind direction fluctuation, the simulation technique of which is now under technical development in our institute.