Author(s)

J. López

Abstract

Influence of the micrometeorological parameters in the estimation of the atmospheric dispersion using theAERMOD J. Lopez Programa de Investigacion del Medio Ambiente y Seguridad (PIMAS), Instituto Mexicano del Petrdleo, Mkxico. Abstract Results of a sensitivity analysis performed on the atmospheric dispersion algorithms of AERMOD with respect to the turbulence parameters in a tropical region are presented. It is also discussed the AERMOD behavior under high moisture and solar radiation meteorological conditions. The sensitivity analysis was carried out running AERMOD under different meteorological scenarios characteristic of a tropical region. Each one of the meteorological parameters, such as wind speed, temperature, friction velocity, convective velocity, Monin- Obukhov length, sensible heat flux, vertical gradient of temperature, and mixing height, was perturbed around a reference meteorological scenario. For each reference scenario, it was considered 37 perturbation levels. The sensitivity analysis shows that wind speed, friction velocity and convective scale velocity are the most relevant meteorological parameters in the estimation of the spatial distribution of the pollutant concentration. Although in a minor degree, it was found that Monin-Obukhov length is also important because it defines which algorithm would be used in according to the prevailing stability conditions. The AERMOD capability to simulate correctly the atmospheric dispersion phenomenon in a tropical region was evaluated by comparing the AERMOD estimates with air quality experimental data. In this case, the simulations were carried out using micrometeorological data and SO2 emission rates measured in situ. The air quality monitoring sites were located downwind from the source within a region where no other SO2 sources exist. Comparison between the model estimates and air quality data indicates that AERMOD can be considered as a good tool to evaluate the environmental impact in a tropical region.

Keywords