The IMADA-AVER Boundary Layer Experiment in the Mexico City Area

Air pollution is a major concern in Mexico City, where high population density (approximately 19 million people in 1000 km), generally light synoptic winds, sheltering by nearby mountains, multiple pollution sources, and strong insolation (which leads to the photochemical formation of ozone) combine to produce frequent episodes of poor air quality (Collins and Scott 1993). As part of an ongoing series of projects to investigate the causes and characteristics of the pollution problem and to develop mitigation methods for it, a field experiment was carried out in the Mexico City area from 24 February through 22 March 1997. The experiment was part of a research program entitled Investigacion sobre Materia Particulada y Deterioro Atmosferico-Aerosol and Visibility Research (IMADA-AVER) and was jointly sponsored by Petróleos Mexicanos (PEMEX) through the Instituto Mexicano del Petróleo (IMP) and the U.S. Department of Energy’s (DOE) Office of Biological and Environmental Research. The objective of the program was to identify the nature and causes of high PM 2.5 and PM 10 concentrations (particles with aerodynamic diameters less than 2.5 and 10 μm, respectively), visibility impairment, and high ozone levels The IMADA-AVER Boundary Layer Experiment in the Mexico City Area