The atmosphere below 200 km over Norilsk at solar minimum and maximum

We have obtained seasonal variations in relative values of the main thermospheric gas components [O]/[N2] and [O2]/[O] during solar maximum. We have used our method and measurements made with the Norilsk digisonde (69.4° N, 88.1° E) at heights of the ionospheric layer F1 (120-200 km) in quiet and disturbed geomagnetic conditions. We have compared [O]/[N2] and [O2]/[O] ratios during solar maximum with the corresponding values for the long period of solar minimum (2007-2009) in Norilsk. The relative content of atomic oxygen particles has been found to increase during solar maximum by more than 35 % in winter and autumn on quiet and disturbed days. In spring and summer, the atmosphere is enriched with molecular oxygen particles by 20 % both on quiet and disturbed days of solar maximum as compared to the conditions of solar minimum.