1. Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Bremerhaven, Germany
2. Johannes Gutenberg University Mainz, Institute for Atmospheric Physics, Mainz, Germany
3. Max Planck Institute for Chemistry, Particle Chemistry Department, Mainz, Germany
4. Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research, Jülich, Germany
5. Air Quality Research Division, Environment and Climate Change Canada, Toronto, Canada