1. Institute for Geosciences, Department of Meteorology, University of Bonn, and Laboratory for Clouds and Precipitation Exploration, Geoverbund ABC/J, Bonn, Germany
2. Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Campus Alpin, Garmisch-Partenkirchen, Germany
3. Agrosphere Institute (IBG-3), Forschungszentrum Jülich, Jülich, Germany
4. Institute for Space Sciences, Freie Universität Berlin, Berlin, Germany
5. Deutscher Wetterdienst, Frankfurt, Germany
6. Institute for Geosciences, Department of Meteorology, University of Bonn, Bonn, Germany