The comprehensive two dimensional advection-diffusion numerical models for primary and secondary pollutants of an urban area source and point source with mesoscale wind are presented. The different removal mechanisms of the primary and secondary pollutants have been taken into account through different parameters like (i) removal by chemical reaction of chemically reactive primary pollutants (ii) removal by means of gravitational settling of larger particles (iii) removal by wet deposition by means of rainout/washout (iv) removal by dry deposition due to absorption by ground surface terrain...