SENSITIVITY ANALYSIS OF AN OPERATIONAL ADVANCED GAUSSIAN MODEL TO DIFFERENT TURBULENT REGIMES

A non-reactive air pollution model evaluating ground level concentrati on is presented. It relies on a new Gaussian for mutation (LUPINI R. a nd TIRABASSI T., J. Appl. Meteor., 20 (1981) 565-570; TIRABASSI T. and RIZZA U., Atmos. Environ., 28 (1994) 611-615) for transport and verti cal diffusion in the Atmospheric Boundary Layer (ABL). In this formula tion, the source height is replaced by a virtual height expressed by s imple functions of meteorological variables. The model accepts a gener al profile of wind u(z) and eddy diffusivity coefficient K-2. The late ral dispersion coefficient is based on Taylor's theory (TAYLOR G. I., Proc. London Math. Sec., 20 (1921) 196-204). The turbulence in the ABL is subdivided into various regimes, each characterized by different p arameters for length and velocity scales. The model performances under unstable conditions have been tested utilizing two different data set s.