Title: Influence of high-model grid resolution on photochemical modelling in very complex terrains

Authors: Pedro Jimenez, Oriol Jorba, Rene Parra, Jose M. Baldasano

Addresses: Laboratory of Environmental Modeling, Universitat Politecnica de Catalunya (UPC), Av. Diagonal 647, 08028 Barcelona, Spain. ' Laboratory of Environmental Modeling, Universitat Politecnica de Catalunya (UPC), Av. Diagonal 647, 08028 Barcelona, Spain. ' Laboratory of Environmental Modeling, Universitat Politecnica de Catalunya (UPC), Av. Diagonal 647, 08028 Barcelona, Spain. ' Laboratory of Environmental Modeling, Universitat Politecnica de Catalunya (UPC), Av. Diagonal 647, 08028 Barcelona, Spain

Abstract: The study of photochemical pollution in very complex terrains, such as the Northeastern Iberian Peninsula (NEIP), is primarily influenced by local topography. This kind of study demands a high spatial resolution. In order to illustrate the influence of the grid resolution on tropospheric ozone levels, several simulations were carried out with MM5-EMICAT2000-CMAQ model using horizontal resolutions ranging from 8, 4 and 2 km and with 6 or 16 vertical layers during an episode of photochemical pollution (13–16 August 2000). High resolutions lead to improve discrete and categorical statistical parameters when evaluating the model against meteorological and air quality data. Results show that coarser grids tend to present a homogeneous and smoothened behaviour of wind flows. Also, results do not manage to describe the particularities of the circulations of the region. Coarser simulations underestimate maximum ozone levels since the grid resolution highly influences the formation and loss processes of ozone.

Keywords: air quality modelling; model evaluation; grid resolution; very complex terrains; atmospheric dispersion modelling; photochemical modelling; air pollution; photochemical pollution; Spain; tropospheric ozone levels; simulation; meteorological data; pollutant concentration.

DOI: 10.1504/IJEP.2005.007393

International Journal of Environment and Pollution, 2005 Vol.24 No.1/2/3/4, pp.180 - 200

Published online: 15 Jul 2005 *

Full-text access for editors Access for subscribers Purchase this article Comment on this article