Mexico City air quality: a qualitative review of gas and aerosol measurements (1960-2000)

Mexico City, one of the largest cities in the world, has a major problem wi th high levels of anthropogenic gases and aerosols. Some facets of this pro blem have been studied through measurements made during the past 40 years. These measurements are reviewed and evaluated with respect to physical proc esses that underlie the primary and secondary formation of gases and aeroso ls, their spatial and temporal evolution as well as their potential impact on the local and regional environment. Past measurements are heavily biased towards certain locations and time periods, and are of limited use for und erstanding fundamental processes that govern the formation and evolution of the principal pollutants. Recommendations are made whereby the measurement database could be expanded to better represent the characteristics of Mexi co City gases and aerosols and to contribute to mitigation strategies that would lessen the environmental impact of these pollutants. (C) 2001 Elsevie r Science Ltd. All rights reserved.