Air quality modeling associated with emission scenarios has become an important tool for air quality management. The set-up of realistic emission scenarios requires accurate emission inventories including the whole methodology used to calculate the emissions. This means a good description of the source characteristics including a detailed composition of the emitted fluxes. Two main approaches are used. The so-called bottom-up approach that relies on the modification of the characteristics of the sources and the top-down approach whose goal is generally to reach standard pollutant concentration levels.

Figure 1: General method of impact assessment using emission reference and scenarios.

The main purpose of my Ph.D. thesis was to study the effects on the air quality of using reformulated and oxygenated gasoline fuel blends. This work intended to address the impacts of these fuels on the emissions of primary and secondary pollutants with respect to the specific European car fleet and VOC emissions. Indeed, since the systematic use of fossil carbon as energetic resource, the quality of the atmospheric environment is dramatically degrading. More and more major cities are concerned with the increase of the occurrence of photochemical pollution episodes. One of the main anthropogenic sources of pollutants is road traffic. The use of alternative fuels has been suggested, at the end of the eighties, in order to improve urban air quality by reducing combustion-related pollution. Reformulating the fuel content, e.g. lowering the fraction of aromatic compounds, and using oxygenated additives such as the Ethyl Tertio-Butyl Ether (ETBE) modify the composition of the emissions leading to reductions some of the most reactive pollutants. The effects were evaluated building the appropriate emission inventories, modeling the air quality for a given polluted episode and performing prospective air quality simulations using the emission scenarios.

I am pursuing this line of research working on improving the methods used to create emission inventories but also on how to extract sub-grid scale variability of emission fluxes and to transfer this information to the upper atmospheric levels.

References:

• Vinuesa J.-F., Ph. Mirabel, and J.-L. Ponche, 2003: Air quality effects of using reformulated and oxygenated gasoline fuel blends: application to the Strasbourg area. Atmospheric Environment, 37, 1757-1774.
• Ponche J.-L. , and J.-F. Vinuesa, 2005: Emission scenarios for air quality management and applications at local and regional scales including the effects of the future European emission regulation (2015) for the upper Rhine valley, Atmospheric Chemistry and Physics, 5, 999-1014.
• Vinuesa J.-F., Ph. Mirabel, and J.-L. Ponche, 2006: Impacts of using reformulated and oxygenated fuel blends on the regional air quality of the upper Rhine valley, Atmospheric Chemistry and Physics, 6, 2161-2176.
• Samaali M. , S. François, J.-F. Vinuesa, and J.-L. Ponche, 2007: A new tool for processing atmospheric emission inventories: technical aspects and application to the ESCOMPTE study area, Environmental Modeling and Software, 22, 1765-1774.
• Galmarini S. , J.-F. Vinuesa, and A. Martilli, 2007: Modelling the impact of sub-grid scale emission variability on upper-air concentration, Atmospheric Chemistry and Physics Discussions, 7, 12289- 12326.