Vladimir Truhlik¹, Dieter Bilitza^2,3, Philip G Richards⁴, Dmytro V. Kotov⁵, Ludmila Triskova⁶ and Maryna O. Shulha⁵, (1)Institute of Atmospheric Physics CAS, Department of Ionosphere and Aeronomy, Praha, Czech Republic, (2)George Mason University Fairfax, Department of Physics and Astronomy, Fairfax, VA, United States, (3)NASA Goddard Space Flight Center, Code 672, Greenbelt, MD, United States, (4)The University of Alabama in Huntsville, Huntsville, AL, United States, (5)Institute of Ionosphere, Kharkiv, Ukraine, (6)Institute Atmospheric Physics CAS, Department of Ionosphere and Aeronomy, Praha, Czech Republic