Eleni Marinou, Vassilis Amiridis, Peristera Paschou, Alexandra Tsekeri, Ioanna Tsikoudi, Kaliopi-Artemis Voudouri, Anna Gialitaki, Maria Tsichla, Kyriaki Papachristopoulou, Dimitra Kouklaki, Iliana Koutsoupi, National Observatory of Athens (NOA), Greece; Elina Giannakaki, University of Athens (UoA), Greece; Stelios Kazadzis, Physics and Meteorology Observatorium of Davos (PMOD), Switzerland; Dimitris Balis, Kostantinos Michailidis, Georgia Peletidou, Aristotle University of Thessaloniki (AUTH), Greece; Anca Nemuc, Doina Nicolae, National Institute of Research & Development for Optoelectronics (INOE), Romania; Grisa Močnik, University of Nova Gorica (UNG), Slovenia; Franco Marenco, Maria Kezoudi, The Cyprus Institute (CyI), Cyprus; Silke Gross, Martin Wirth, Florian Ewald, German Aerospace Center (DLR), Germany; Ewan O'Connor, Ville Vakkari, Dmitri Moisseev, Finnish Meteorological Institute (FMI), Finland; Pavlos Kollias, Stony Brook University, United States; Lucia Mona, Nikos Papagiannopoulous, Marco Rosoldi, Consiglio Nazionale delle Ricerche (CNR), Italy; Rodanthi-Elisavet Mamouri, Dragos Ene, Cyprus University of Technology (CUT), Cyprus; Athina Floutsi, Holger Baars, Leibniz Institute for Tropospheric Research (TROPOS), Germany