Effects of the global economic crisis on the emissions of air pollutants and environmental policies in Mexico City

摘要

The financial markets registered historical losses due to the 2008 global economic crisis. The prime causes are well-known and its direct consequences have become poignantly evident: economic recession unleashing daily-increments in unemployment figures, breakdown of industries , and governments and, last but not least, accentuated poverty increments. Nevertheless some consequences are no so evident: the question arises, what will the global crisis effects be on the environment? Will the air quality management programs be affected? In this work we analyze the consequences, challenges and opportunities related with the global economic crisis and the Air Quality Management, taking as a case study the Green Plan of Mexico City. With the aim to evaluate the Green Plan actions related with air quality, several econometric models were developed for each type of vehicle considering the emission inventory. The economic variables were obtained with serial times using the published studies of the Bank of Mexico and the National Institute of Geography and Informatics (INEGI). Car withdrawal curves were obtained with multiple linear regressions and empirical models using data from the Mexico City's Ministry of Environment (SMADF). Emission factor tables were constructed based in material balances for carbon dioxide emissions and other pollutants. These models allow the evaluation, analyses and observation of the economic variables on the emission inventory. The econometric models related to car sales (national and imported) showed the different stages of the Mexican economic crisis development. The relationship with the vehicle market behavior allowed the analysis of the crisis effects on the air pollution and greenhouse gas emissions. The findings show that aging of the vehicle fleet is and will be one of the consequences of the crisis. In Mexico City's Metropolitan Area, during 2007 and 2008, approximately 242.774 and 176.036 tons of additional pollutants were emitted, respectively, as well as around 900,000 additional greenhouse gases each year increasing up to 2.6%, 8.2%, 2% and 35% the O_3, CO_2, CH_4 and N_2O concentrations respectively due to the effect of the vehicle fleet aging; the point is, this situation could well continue until the economy recovers. Several projections were performed to implement the Strategic Environmental Assessment (SEA) with the aim to promote this practice in the environmental management system in Mexico to contribute to an efficient use of resources and improve decision-making. It is necessary to create an environmental management system that actually leads us to sustainability, especially in transport policy as it had been recommended by the OECD in its 2003 assessment.