88th Annual Meeting (20-24 January 2008)

Tuesday, 22 January 2008: 9:00 AM
Coupling atmospheric chemistry/aerosols to regional climate model in high resolution
230 (Ernest N. Morial Convention Center)
Tomas Halenka, Charles Univ., Prague, Czech Republic; and P. Huszar and M. Belda
Recently the effects of climate change on air-quality and vice-versa are studied quite extensively. In fact, even at regional and local scale especially the impact of climate change on the atmospheric composition and photochemical smog formation conditions can be significant when expecting e.g. more frequent appearance of heat waves etc. For the purpose of qualifying and quantifying the magnitude of such effects and to study the potential of climate forcing due to atmospheric chemistry/aerosols on regional scale, the development of coupling of regional climate model and chemistry/aerosol model has been started recently on the Department of Meteorology and Environmental Protection, Faculty of Mathematics and Physics, Charles University in Prague. For this coupling, existing regional climate model and chemistry transport model are used. Regional climate simulations are calculated using model RegCM while chemistry and aerosols are solved by model CAMx. Meteorological fields generated by RegCM drive CAMx transport, dry/wet deposition as well as the chemistry of the species. A pre-processor utility was developed on the department for transforming RegCM provided fields to CAMx input fields and format. As the first step, off-line one way coupling enable the simulation of distribution of pollutants over longer period of years. There is critical issue of the emission inventories available when going to very high resolution of 10 km as scheduled in framework of ongoing EC FP6 project CECILIA. Long period runs of one way coupled climate/chemistry/aerosol models are scheduled in this project with further studies of on-line impact implementation in regional climate simulations. At this moment, one way coupling on lower resolution is compared with the high resolution simulation at 10 km nested into the lower resolution run to have better boundary conditions both for meteorology and chemistry for year 2000. Reasonable improvement of the results can be seen with respect to lower resolution run and departures from measured values on selected air-quality stations. Sensitivity of the model couple to the development of urban and industrialized areas, transportation as well as the impact of changes in natural emissions due to land use changes for the central Europe is studied for the EC projects QUANTIFY and CECILIA as well.

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