1. a TNO Defence, Security and Safety , Oude Waalsdorperweg 63, P.O. Box 96864, 2509, JG, The Hague, The Netherlands
2. b University of Toulon-Var , LSEET-LEPI, bât F, BP20132, 83957, La Garde Cedex, France
3. c Atmospheric Optics Group (GOA), University of Valladolid , Prado de la Magdalena s/n, 47071, Valladolid, Spain
4. d TNO B&O , Princetonlaan 6, Postbus 80015, 3508, TA, Utrecht, The Netherlands
5. e Finnish Meteorological Institute (FMI), Climate Change Unit , Erik Palmenin Aukio 1, P.O. Box 503, FI-00101, Helsinki, Finland
6. f University of Helsinki, Department of Physics , P.O. Box 64, FI-00014, Helsinki, Finland
7. g Royal Netherlands Meteorological Institute (KNMI) , Wilhelminalaan 10, Postbus 201, 3730, AE, De Bilt, The Netherlands