1. CNR-Institute of Atmospheric Pollution Research, Division of Rende; UNICAL-Polifunzionale; Rende Italy
2. Dipartimento di Fisica; Università della Calabria; Rende Italy
3. U. S. Environmental Protection Agency, Office of Research and Development; Research Triangle Park; Durham NC USA
4. Department of Environmental Science; Aarhus University; Roskilde Denmark
5. Norwegian Institute for Air Research (NILU); Kjeller Norway
6. NCAS, National Centre for Atmospheric Sciences; University of York; York UK
7. Cape Point GAW Station, Climate and Environment Research and Monitoring; South African Weather Service; Stellenbosch South Africa
8. University Grenoble Alpes, CNRS, IRD, IGE; Grenoble France
9. Now at Institute for Data, Systems, and Society; Massachusetts Institute of Technology; Cambridge MA USA
10. CNR-Institute of Atmospheric Pollution Research; Area della Ricerca di Roma 1; Monterotondo Italy