RESUMO
A black carbon (BC) emission inventory for Mexico is presented. Estimate was performed by using two approaches, based on fuel consumption and emission factors in a top-down scheme, and the second from PM25 emission data and its correlation with black carbon by source category, assuming that black carbon=elemental carbon. Results show that black carbon emissions are in interval 53-473Gg using the fuel consumption approach and between 62 and 89 using the sector method. Black carbon key sources come from biomass burning in the rural sector, with 47 percent share to the National total. Mobile sources emissions account to 16% to the total. An opportunity to reduce, in the short-term, carbon dioxide equivalent (CO2-eq) emissions by reducing black carbon emissions would be obtained in reducing emissions mainly from biomass burning in rural housing sector and diesel emissions in the transport sector with important co-benefits in direct radiative forcing, public health and air quality.
Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Fuligem/análise , MéxicoRESUMO
Results of a field study on the efficiency of vapor recovery systems currently used in gasoline service stations in Mexico City are presented. Nine gasoline stations were studied, representing the several technologies available in Mexico City. The test was applied to a fixed vehicular fleet of approximately 10 private and public service vehicles. Each one of the gasoline service stations tested reported efficiencies above 80% in the recovery of vapor losses from gasoline which is the minimum permissible value by Mexican regulations. Implications to the emissions inventory are discussed. A second goal of this study was to measure the potential exposure of service attendants to three important components of gasoline: benzene; toluene; and xylenes. The influence of spatial location of personnel within the service station was also evaluated by measuring levels of the three compounds both at the refueling area and in the service station office. Results are discussed and compared to a previous study.
Assuntos
Poluição do Ar/prevenção & controle , Exposição Ambiental , Hidrocarbonetos/análise , Exposição Ocupacional , Saúde Pública , Emissões de Veículos/análise , Cidades , Monitoramento Ambiental/métodos , Humanos , México , Petróleo , Meios de Transporte , População Urbana , VolatilizaçãoRESUMO
Using an air quality model, two future urban scenarios induced by the construction of the new international airport for Mexico City are compared at a regional level. The air quality model couples the meteorology model MM5 and state-of-the-art photochemistry. The air quality comparison is made using metrics for the criterion gases selected for the study. From the two urban scenarios compared, the option for Tizayuca is moderately better than the option for Texcoco, because relative reductions in O3 and other photochemical pollutants are achieved over highly populated areas. Regardless of the site, the air quality for the central region of Mexico in the future will deteriorate. In the region of central Mexico, SO2 and NO2 will become important pollutants.