Irkutsk, Russian Federation
Irkutsk, Russian Federation
Irkutsk, Russian Federation
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.
gas component ratios, geomagnetic disturbances
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