AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Modeling of Carbonaceous Aerosol in a European Megacity
CHRISTOS FOUNTOUKIS, Athanasios Megaritis, Ksakousti Skyllakou, Panagiotis Charalampidis, Christodoulos Pilinis, Spyros Pandis, Foundation for Research & Technology, Hellas
Abstract Number: 266 Working Group: Carbonaceous Aerosols in the Atmosphere
Abstract Three dimensional Eulerian Chemical Transport Models (CTMs) are often used for the design and assessment of air pollution mitigation policies. Grid resolution is a critical factor for these models since a large model grid size cannot capture inhomogeneities in emission rates, meteorology and land cover while a very small grid size makes the simulation inefficient due to the large computational cost. The lack of adequate resolution limits also the ability of the model to accurately simulate individual processes and their interactions. In this work, we use the regional CTM PMCAMx in a two-way nesting configuration (36 × 36 km grid resolution over Europe and 4 × 4 km over Paris) to study the impact of different grid resolutions on fine particulate matter predictions and analyze the sources and production of carbonaceous aerosol in a European metropolitan area of more than 10 million inhabitants. High time resolution AMS measurements were used to evaluate the performance of the model while high resolution (1 x 1 km) emissions are used. The differences between the two grid simulation results in the Paris area are, on average, small for all species during the summer period (July 2009). The 4-km grid simulation captures the average winter diurnal concentration of fine primary organic aerosol and black carbon better than the coarse grid. Particulate matter levels in the Paris megacity are strongly influenced by sources outside the city with the carbonaceous aerosol being mostly of non-fossil fuel origin. About 70% of the fine PM mass is transported into the megacity from continental Europe. Black carbon concentrations (both predicted and observed) are on the lower end of values encountered in megacities worldwide.