The MICTM model has originally been developed at Meteorological Institute, University of Hamburg based on the mesoscale chemistry model MECTM (Grawe, 2005). MICTM is using MITRAS output for the meteorology and employs the same non-uniform grid (areas between 100x100 m2 and 1000x1000 m2 ). Prognostic equations are solved for several pollutants (e.g. NOx, O3, SO2 , NH3, Pb, nitrate, sulphate). The dry deposition is calculated from a resistance model, it depends on pollution and land use characteristics. Chemical transformations are included in the model using the RADM2 gas phase chemistry from Stockwell et al.,. The lateral model boundaries are open or MICTM uses results of a coarser model (e.g. mesoscale model MECTM). At the model top constant concentration values are prescribed. By using meteorology output of MITRAS, MICTM may be employed to calculate pollutant concentrations in the air and the deposition to the ground within street canyons or forests dependent on the emissions. Studies on biogenic emissions may be performed.