An atmosphere-chemistry model on the meso-γ scale: model description and evaluation.

A meso-γ scale non-hydrostatic atmospheric model has been extended to determine gas-phase chemistry, transport, emission and deposition of chemical trace species. This coupled atmosphere-chemistry model calculates meteorological and chemical processes simultaneously. The model is nested into a coarser regional atmosphere-chemistry model which, in turn, is embedded in an even coarser framework. According to the evaluation case, the chain of mesoscale atmosphere-chemistry models is applied to the regions of Europe, Germany and Berlin-Brandenburg, respectively. The model performance is evaluated using time series of meteorological and chemical measurements and aircraft observations. The evaluation shows that the meteorological and chemical simulation reproduces reality excellent under urban conditions. But the amount of rural and upper level ozone is generally too low. [ABSTRACT FROM AUTHOR]