Major volcanic eruptions are emitting huge amounts of ash particles and gaseous precursors of secondary aerosols into the atmosphere. These particles can endanger air traffic and they have an impact on climate and most probably also on weather. The particles are interacting with atmospheric radiation and they can modify the formation of cloud by several physical processes.
For those reasons there exists a great interest of atmospheric scientist and end users to forecast the spatial and temporal distribution of particles of volcanic origin. This is one of the main focal points of the DFG Forschergruppe VolImpact.
The presentation will explain how these forecasts are currently done and where the main problems are. It will highlight which physical and chemical processes are of importance, where Mie theory helps to improve the forecast quality, and where it fails.