Sensitivity of Atmospheric Chemistry/Aerosols Model Coupled to

Recent studies show effect of atmospheric chemistry and aerosols on climate on regional and local scales. For the purpose of qualifying and quantifying the magnitude of climate forcing due to tropospheric ozone on regional scale, the development of coupling of regional climate model and chemistry/aerosol model was started for the EC 6FP Projects QUANTIFY and CECILIA. Climate is calculated using model RegCM while chemistry is solved by model CAMx. A preprocessor utility was developed on the department for transforming RegCM provided fields to CAMx input fields and format. Meteorological fields generated by RegCM drive CAMx transport and dry/wet deposition.

As the first step, the distribution of pollutants is simulated off-line in the model couple. There is critical issue of the emission inventories available when going to very high resolution of 10 km as scheduled in framework of CECILIA Project. Sensitivity of the model couple to the high resolution land use with emphasis to the possible changes of biogenic emissions and interactions with the other sources of emissions is studied for the EC projects QUANTIFY and CECILIA. Results of the ozone and its precursors concentrations are compared with measured data for reanalysis driven run. Long period runs of one way coupled climate/chemistry/aerosol models have been completed in this project with further studies of on-line impact implementation in regional climate simulations.

The concept of effective emission indices is applied to introduce the difference between the real emission effects and emission diluted in the scale of model grid for ship emission effect parameterization for project QUANTIFY. Sensitivity of the inclusion of this technique on the chemistry will be presented.