Air quality modelling over Bogota, Colombia: Combined techniques to estimate and evaluate emission inventories

Erika Zarate (1) , Luis Carlos Belalcazar (2) , Alain Clappier (3) , Veronica Manzi (2) , Hubert van den Bergh (1)

1 LPAS - EPFL Air and Soil Pollution Laboratory
2 UNIANDES - Departamento de Ingeniería Civil y Ambiental [Univ de los Andes Colombia]
3 LPAS - EPFL Air and Soil Pollution Laboratory

Two versions of the Emission Inventory (EI) are generated for the city of Bogota, Colombia. In the first version (EI-1), CORINAIR traffic emission factors (EFs) are used. In the second (EI-2), bulk traffic EFs calculated for the city, using in situ measurements and inverse modelling techniques at street level, are used. EI-2 traffic emissions are 5, 4 and 3 times bigger than the corresponding values in EI-1, for CO, PM10 and NMVOCs, respectively. The main goal of this study consists in evaluating the two versions of the EI when introduced into a mesoscale air quality model. The AOT (accumulated exposure over a threshold) index is calculated for comparison between observed and simulated concentrations of primary pollutants. Simulated concentrations using EI-2 are closer to the observed values. This comparison allows us to extract some conclusions of the methodology used to calculate the EFs. Local factors like the driving behavior, the altitude, vehicle technology and an aged fleet cannot be totally included and corrected in the standard methodologies, and seem to be more important than obtaining very detailed and precise information on the classification of the fleet or driving speeds. Under financially limited and fast changing situations, as in the case of many developing countries, a simple methodology to estimate bulk traffic EFs and to evaluate the EI, is of utmost importance. The use of combined techniques such as in situ measurements to estimate bulk traffic EFs, and further evaluation of the inventories with numerical models, proved to be a useful tool for this purpose.

Mots clés: Bogota; Emission Inventory; real-world emissions; urban air pollution; air quality management

Domaines: Sciences de l'Homme et Société; Océan, Atmosphère

Erika Zarate, Luis Carlos Belalcazar, Alain Clappier, Veronica Manzi, Hubert van den Bergh. Air quality modelling over Bogota, Colombia: Combined techniques to estimate and evaluate emission inventories. Atmospheric Environment, 2007, 41 (29), pp.6302-6318. ⟨10.1016/j.atmosenv.2007.03.011⟩. ⟨halshs-00545912⟩