The chemical composition of the atmospheric boundary layer and its evolution under the influence of anthhropic pollutant emissions are key issues in atmospheric sciences. Any change in the atmospheric composition has various important impact on, for instance, global warming, aerosol formation, and more generally atmospheric pollution. The air quality is strongly associated with the quality of life of the population. Therefore pollution phenomena have important social and economical impacts. The operational measurements of pollutant concentrations done by the air quality networks are used to inform the population and more and more to help decision-makers to take actions to improve the air quality. Nevertheless, these latter networks are only able to provide punctual measurements and these informations do not take into account the heterogeneity of the concentration fields. Moreover, the air quality of a certain location depends on synoptic situation, local meteorology, local emission and long-range transport of pollutants.

The complete set of these driving processes has to be integrated to address the chemical transformation of pollutants in the lower atmosphere, for instance as:

Therefore air quality constitutes an highly interdisciplinary issue including both boundary layer physics and tropospheric chemistry. With that respect, air quality modeling is one of the perfect tool for atmospheric environment management. It can be used to analyse pollution episodes or to determine the more efficient emission management for the decrease of secondary atmospheric pollutants formation.

Emission scenarios coupled with chemical transport modeling are of major importance for air quality management. Several issues can be investigated including local authorities goals (e.g., air quality management plans, atmospheric protection plans) and scientific applications (e.g., air quality analysis, transport and deposition study, improvement fuel processes). However, air quality modeling requiers at least three tools, i.e., a spatialized emission inventory, a meteorological model, and a chemical transport model.