Sergey Khaykin¹, Martina Kraemer², Elisabeth J Moyer³, Alexey Lykov⁴, Silvia Bucci⁵, Armin Afchine², Stephan Borrmann⁶, Francesco Cairo⁷, Benjamin Clouser³, Francesco D’Amato⁸, Bernad Legras⁹, Velentin Mitev¹⁰, Renaud Matthey¹¹, Fabrizio Ravegnani⁷, Christian Rolf¹², Alexey Ulanovsky¹³, Silvia Viciani⁸, C Michael Volk¹⁴, Vladimir A Yushkov¹³, Fred Stroh¹⁵ and StratoClim aircraft campaign team, (1)LATMOS/IPSL, UVSQ, Sorbonne Université, CNRS, Paris Cedex 05, France, (2)Forschungszentrum Juelich, Juelich, Germany, (3)University of Chicago, Geophysical Sciences, Chicago, IL, United States, (4)Central Aerological Observatory of RosHydroMet, Dolgoprudny, Russia, (5)Laboratoire de Météorologie Dynamique ENS, Paris, France, (6)Johannes Gutenberg University, Max Planck Institute for Chemistry, Particle Chemistry, Mainz, Germany, (7)Institute of Atmospheric Science and Climate, ISAC-CNR, Rome, Italy, (8)CNR-INO National Institute of Optics, Florence, Italy, (9)Laboratoire de Météorologie Dynamique Palaiseau, Palaiseau Cedex, France, (10)Centre Suisse d’Electronique et de Microtechnique Neuchatel, Neuchatel, Switzerland, (11)LTF-University of Neuchatel, Neuchatel, Switzerland, (12)Forschungszentrum Juelich, IEK-7, Juelich, Germany, (13)Central Aerological Observatory of RosHydroMet, Moscow, Russia, (14)Institute for Atmospheric and Environmental Research, University of Wuppertal, Wuppertal, Germany, (15)Forschungszentrum Juelich, Jülich, Germany