1. Aerosol Physics Laboratory, Physics Unit, Tampere University, 33720 Tampere, Finland
2. IVL Swedish Environmental Research Institute, 41133 Gothenburg, Sweden
3. Atmospheric Composition Research, Finnish Meteorological Institute, 00101 Helsinki, Finland
4. Aix Marseille University, CNRS, LCE, 13331 Marseille, France
5. Department of Earth, Space and Environment, Chalmers University of Technology, 41296 Gothenburg, Sweden