Air quality modelling studies in Germany and Europe across scales

The problem of health risks associated with poor air quality in cities and metropolitan areas is rising in the perception of society. In order to improve air quality, a thorough understanding of different emission sources concerning transport, origin and composition as well as the microphysical and chemical processes involved is of crucial importance.

To assess air quality related issues, we set up a simulation system using the global to regional model system MECO(n), which allows entangling of chemical and physical interactions using a dynamical coupling approach from a global to regional domains down to a resolution of ∼7km. This provides us with a detailed picture of air quality in urbanised regions whilst maintaining a consistent representation and implementation of processes across the scales.

The model setup is evaluated using measurement data from the aerosol robotic network (AERONET) and satellite data from VIIRS instrument on board the polarorbiting Suomi NPP satellite. Moreover we compare our model to ground based measurements of gas species and particulate matter, which are taken from the databases of the Environmental Protection Agency of Rhineland-Palatinate. In this context the limits of the model with respect to aerosol processes especially in the boundary layer are discussed and the resulting limitations in comparing our model output to ground based measurements of particulate matter, specifically PM_2.5 and PM₁₀ are shown.

To demonstrate the flexibility of the model system two model applications relevant for air pollution issues in the Rhine-Main region are presented. The first investigates the direct influence of a localised reduction in anthropogenic emissions on the surrounding regions and the reducing region itself. The second explores deposition regions of kerosene, which is released by aircrafts during emergency fuel dumping event.