1. Université Grenoble-Alpes, CNRS, IRD, INP, INRAE, IGE, Grenoble, France;
2. Institute for Atmospheric and Earth System Research/Physics, University of Helsinki, Helsinki, Finland;
3. The Climate and Environmental Research Institute NILU, Kjeller, Norway;
4. IMT Nord Europe, Institut Mines-Télécom, Université Lille, Centre for Energy and Environment, Lille, France;
5. National Observatory of Athens, Athens, Greece;
6. Institute of Energy and Climate Research, IEK-8: Troposphere, Forschungszentrum Jülich GmbH, Jülich, Germany;
7. Department of Physics, University of Cologne, Cologne, Germany;
8. Environmental Radioactivity and Aerosol Technology for Atmospheric and Climate ImpacT Lab, INRaSTES, National Centre for Scientific Research Demokritos, Attiki, Greece;
9. ACTRIS ERIC, Helsinki, Finland;
10. Finnish Meteorological Institute, Helsinki, Finland;
11. Centre National de Recherche Scientifique, Laboratoire de Météorologie Physique, Aubière, France;
12. Consiglio Nazionale delle Ricerche-Istituto di Metodologie per l’Analisi Ambientale, Tito Scalo, Italy;
13. Andalusian Institute for Earth System Research (IISTA-CEAMA), University of Granada, Granada, Spain;
14. Leibniz Institute for Tropospheric Research (TROPOS), Leipzig, Germany;
15. Meteorological Observatory Hohenpeissenberg, Deutscher Wetterdienst, Hohenpeissenberg, Germany;
16. Royal Belgian Institute for Space Aeronomy (BIRA-IASB), Brussels, Belgium;
17. Institut National de l’Environnement Industriel et des Risques, Verneuil-en-Halatte, France;
18. Institut Pierre Simon Laplace, CNRS, Institut Polytechnique de Paris, Palaiseau, France;
19. Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research, Eggenstein-Leopoldshafen, Germany;
20. Institute for Atmospheric and Environmental Research, University of Wuppertal, Wuppertal, Germany;
21. Medical University of Innsbruck, Innsbruck, Austria;
22. LuftBlick OG, Innsbruck, Austria;
23. GeoSphere Austria, Department Sonnblick Observatory, Vienna, Austria;
24. National Institute of R&D for Optoelectronics, Măgurele, Romania;
25. Université Paris Est Créteil and Université Paris Cité, CNRS, LISA, Créteil, France;
26. Institute for Geophysics and Meteorology, University of Cologne, Cologne, Germany;
27. European Commission, Joint Research Centre, Ispra, Varese, Italy;
28. Empa, Laboratory for Air Pollution/Environmental Technology, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland;
29. Ludwig-Maximilian University of Munich, Munich, Germany;
30. University of Warsaw, Faculty of Physics, Institute of Geophysics, Warsaw, Poland;
31. Royal Netherlands Meteorological Institute (KNMI), De Bilt, Netherlands;
32. CommSensLab, Department TSC, Universitat Politècnica de Catalunya, Barcelona, Spain;
33. Paul Scherrer Institute, Laboratory of Atmospheric Chemistry, Villigen, Switzerland;
34. University of Crete, Heraklion, Greece;
35. Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia, Bulgaria;
36. Institute of Geophysics Polish Academy of Sciences, Warsaw, Poland;
37. Climate and Atmosphere Research Center, The Cyprus Institute, Nicosia, Cyprus;
38. Department of Environmental Science, Aarhus University, iCLIMATE, ARC, Aarhus, Denmark;
39. Department of Physics, Lund University, Lund, Sweden;
40. National Centre for Atmospheric Science, Leeds, United Kingdom;
41. University of Manchester, Manchester, United Kingdom;
42. Institute of Chemical Process Fundamentals of CAS, Prague, Czech Republic;
43. Natural Resources Institute, Helsinki, Finland;
44. Czech Hydrometeorological Institute, Prague, Czech Republic