Trends in exhaust emissions from in-use Mexico City vehicles, 2000–2006. A remote sensing study

Schifter, I.; Díaz, Luis A.; Rodriguez, R.; Duran, J; Chávez, Othón González

doi:10.1007/s10661-007-9781-4

Cited by 21 publications

(22 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 2 shows a comparison of the gasoline fleet average fuelbased emission factors presented in this work (using the excess plume of CO+CO 2 ) with those measured by remote sensing in 2000 and 2006 in Mexico City (Schifter et al, 2003(Schifter et al, , 2008 Although gasoline emissions in Mexico City could, in principle, tend to be higher than in US cities because of its location at higher altitude (∼2200 m a.s.l. ), vehicles are generally provided with a mechanism for compensating the effect of altitude on air density.…”

Section: Comparison Of On-road and Cross-road (Remote Sensing) Resultsmentioning

confidence: 98%

“…Even using the wider range of 0.13-0.21 for the VOC/CO mass ratio measured by remote sensing in 2006 from Schifter et al (2008), both the total VOC emissions estimated this way and the emissions directly derived from the remote sensing study indicate an overall underprediction of VOC emissions from mobile sources of a factor between 1.4 and 1.9. The emissions estimated from on-road and remote sensing measurements do not include evaporative or cold start emissions.…”

Section: Vocs Emissionsmentioning

confidence: 91%

“…Using the reported fuel-based emission factors from Bishop and Stedman (2008), the VOC/CO mass ratio of mobile emissions in US cities increased from 0. (Schifter et al, 2008).…”

Section: Vocs Emissionsmentioning

confidence: 99%

See 2 more Smart Citations

Evaluation of mobile emissions contributions to Mexico City's emissions inventory using on-road and cross-road emission measurements and ambient data

et al. 2009

View full text Add to dashboard Cite

Abstract. Mobile emissions represent a significant fraction of the total anthropogenic emissions burden in the Mexico City Metropolitan Area (MCMA) and, therefore, it is crucial to use top-down techniques informed by on-road exhaust measurements to evaluate and improve traditional bottom-up official emissions inventory (EI) for the city. We present the measurements of on-road fleet-average emission factors obtained using the Aerodyne mobile laboratory in the MCMA in March 2006 as part of the MILAGRO/MCMA-2006 field campaign. A comparison of our on-road emission measurements with those obtained in 2003 using essentially the same measurement techniques and analysis methods indicates that, in the three year span, NO emission factors remain within the measured variability ranges whereas emission factors of aldehydes and aromatics species were reduced for all sampled driving conditions.We use a top-down fuel-based approach to evaluate the mobile emissions from the gasoline fleet estimated in the bottom-up official 2006 MCMA mobile sources. Within the range of measurement uncertainties, we found probable slight overpredictions of mean EI estimates on the order of 20-28% for CO and 14-20% for NO. However, we identify a probable EI discrepancy of VOC mobile emissions between 1.4 and 1.9; although estimated benzene and toluene mobile emissions in the inventory seem to be well within the uncertainties of the corresponding emissions estimates. Aldehydes mobile emissions in the inventory, however, seem to be unCorrespondence to: M. Zavala (miguelz@mce2.org) derpredicted by factors of 3 for HCHO and 2 for CH 3 CHO. Our on-road measurement-based estimate of annual emissions of organic mass from PM 1 particles suggests a severe underprediction (larger than a factor of 4) of PM 2.5 mobile emissions in the inventory.Analyses of ambient CO, NO x and CO/NO x concentration trends in the MCMA indicate that the early morning ambient CO/NO x ratio has decreased at a rate of about 1.9 ppm/ppm/year over the last two decades due to reductions in CO levels rather than by NO x . These trends, together with the analysis of fuel sales and fleet size, suggest that the relative contribution of diesel vehicles to overall NO x levels has increased over time in the city. Despite the impressive increase in the size of the vehicle fleet between 2000 and 2006, the early morning ambient concentrations of CO and NO x have not increased accordingly, probably due to the reported low removal rates of older vehicles, which do not have emissions control technologies, and partially due to the much lower emissions from newer gasoline vehicles. This indicates that an emission-based air quality improvement strategy targeting large reductions of emissions from mobile sources should be directed towards a significant increase of the removal rate of older, highly-polluting, vehicles.

show abstract

Section: Comparison Of On-road and Cross-road (Remote Sensing) Resultsmentioning

confidence: 98%

Section: Vocs Emissionsmentioning

confidence: 91%

See 1 more Smart Citation

Evaluation of mobile emissions contributions to Mexico City's emissions inventory using on-road and cross-road emission measurements and ambient data

et al. 2009

View full text Add to dashboard Cite

show abstract

“…b Total VOCs emissions from the inventory include evaporative emissions. The corresponding on-road VOC's are inferred rather than measured scaling CO emissions by a remote-sensing-based VOC/CO ratio (Schifter et al, 2008). Estimated organic mass of particles in the non-refractory PM 1 range.…”

Section: Mobile Emissions Measurementsmentioning

confidence: 99%

An overview of the MILAGRO 2006 Campaign: Mexico City emissions and their transport and transformation

et al. 2010

View full text Add to dashboard Cite

Abstract. MILAGRO (Megacity Initiative: Local And Global Research Observations) is an international collaborative project to examine the behavior and the export of atmospheric emissions from a megacity. The Mexico City Metropolitan Area (MCMA) -one of the world's largest megacities and North America's most populous city -was selected as the case study to characterize the sources, concentrations, transport, and transformation processes of the gases and fine particles emitted to the MCMA atmosphere and to evaluate the regional and global impacts of these emissions. The findings of this study are relevant to the evolution and impacts of pollution from many other megacities.The measurement phase consisted of a month-long series of carefully coordinated observations of the chemistry and physics of the atmosphere in and near Mexico City duringCorrespondence to: L. T. Molina (ltmolina@mit.edu) March 2006, using a wide range of instruments at ground sites, on aircraft and satellites, and enlisting over 450 scientists from 150 institutions in 30 countries. Three ground supersites were set up to examine the evolution of the primary emitted gases and fine particles. Additional platforms in or near Mexico City included mobile vans containing scientific laboratories and mobile and stationary upward-looking lidars. Seven instrumented research aircraft provided information about the atmosphere over a large region and at various altitudes. Satellite-based instruments peered down into the atmosphere, providing even larger geographical coverage. The overall campaign was complemented by meteorological forecasting and numerical simulations, satellite observations and surface networks. Together, these research observations have provided the most comprehensive characterization of the MCMA's urban and regional atmospheric composition and chemistry that will take years to analyze and evaluate fully.Published by Copernicus Publications on behalf of the European Geosciences Union. L. T. Molina et al.: Mexico City emissions and their transport and transformationIn this paper we review over 120 papers resulting from the MILAGRO/INTEX-B Campaign that have been published or submitted, as well as relevant papers from the earlier MCMA-2003 Campaign, with the aim of providing a road map for the scientific community interested in understanding the emissions from a megacity such as the MCMA and their impacts on air quality and climate. This paper describes the measurements performed during MILAGRO and the results obtained on MCMA's atmospheric meteorology and dynamics, emissions of gases and fine particles, sources and concentrations of volatile organic compounds, urban and regional photochemistry, ambient particulate matter, aerosol radiative properties, urban plume characterization, and health studies. A summary of key findings from the field study is presented.

show abstract

“…More recent measurements of emissions factors from mobile sources in Mexico City under realworld driving conditions were obtained using remote sensing techniques (Schifter et al, 2003c(Schifter et al, , 2008, and mobile laboratory measurement techniques in the dedicated MCMA-2002MCMA- /2003 and MILAGRO/MCMA-2006 field campaigns (Jiang et al, 2005;Rogers et al, 2006;Zavala et al, 2006Zavala et al, , 2009aThornhill et al, 2010). These studies provided valuable information on the chemical composition of gases and PM emitted from mobile sources in Mexico City and highlighted the important contributions of emissions from diesel-powered vehicles to pollutants concentration levels in Mexico City.…”

Section: Introductionmentioning

confidence: 99%

Analysis of model-based PM2.5 emission factors for on-road mobile sources in Mexico

Zavala¹,

Barrera²,

Morante³

et al. 2013

Atmósfera

View full text Add to dashboard Cite

RESUMENSe investigan los resultados del empleo del modelo US-EPA MOVES2010a para calcular los factores de emisión del parque vehicular mexicano, y se comparan dichos resultados con las estimaciones del Inventario Nacional de Emisiones de México (INEM) de 2005. El estudio muestra que los factores de emisión PM2.5 basados en modelos, actualizados a partir de estudios recientes, pueden tener un impacto significativo en la estimación de emisiones de PM2.5 procedentes de fuentes móviles en México. Porcentajes mayores de vehículos antiguos tienden a incrementar las estimaciones de emisiones PM2.5 cuando se utiliza el modelo MOVES2010a en comparación con las del INEM 2005; sin embargo, el impacto global sobre las emisiones de material particulado varía según la cantidad y antigüedad de los vehículos, y de acuerdo con los porcentajes de vehículos antiguos impulsados por diesel y gasolina en el parque vehicular de cada entidad federativa. Los resultados también indican que las estimaciones de PM2.5 con MOVES2010a fueron particularmente sensibles a la velocidad vehicular, la temperatura ambiente y el contenido de azufre, pero no a la humedad relativa. Hay una gran necesidad de comprender las características del material particulado fino emitido por vehículos impulsados por diesel o gasolina en las principales zonas urbanas de México. ABSTRACTThis study investigates the effects of using the US-EPA MOVES2010a model for estimating PM2.5 emission factors in the Mexican vehicle fleet; the results are compared with the current PM2.5 emissions estimates in the 2005 Mexican National Emissions Inventory (MNEI). Our results show that model-based PM2.5 emissions factors updated from recent studies can have significant impacts on the estimated PM2.5 emissions from mobile sources in Mexico. Higher fractions of older vehicles tend to increase PM2.5 emissions estimates using MOVES2010a with respect to the 2005 MNEI estimates; however, the overall impact on PM emissions varies depending on the vehicle population and vehicle age composition for each Mexican state fleet. These effects are primarily driven by the higher PM2.5 emission factors from the gasoline-powered vehicles and by the high fractions of older gasoline and diesel vehicles. The results also indicate that the estimated MOVES2010a PM2.5 emission factors for Mexico were particularly sensitive to vehicle speed, ambient temperature and sulfur content, but not the relative humidity. There is a strong need to better understand the characteristics of fine particulate matter (PM) emitted from gasoline and diesel-powered vehicles in major urban areas in Mexico.Keywords: PM2.5 emission factors, mobile sources, emissions inventory.Atmósfera 26(1), 109-124 (2013) 110 M. Zavala et al. IntroductionThe effects of atmospheric particulate matter (PM) on human health have been well documented in recent years; the overall literature provides reasonably compelling evidence that ambient PM air pollution contributes to cardiopulmonary morbidity and mortality (e.g., Pope, 2010). There is also e...

show abstract

Trends in exhaust emissions from in-use Mexico City vehicles, 2000–2006. A remote sensing study

Cited by 21 publications

References 13 publications

Evaluation of mobile emissions contributions to Mexico City's emissions inventory using on-road and cross-road emission measurements and ambient data

Evaluation of mobile emissions contributions to Mexico City's emissions inventory using on-road and cross-road emission measurements and ambient data

An overview of the MILAGRO 2006 Campaign: Mexico City emissions and their transport and transformation

Analysis of model-based PM2.5 emission factors for on-road mobile sources in Mexico

Contact Info

Product

Resources

About