Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 15174 10.12737/24278 Results of current research Results of current research Results of current research Long-term variations in the neutral gas composition of the thermosphere over Norilsk (2003–2013) Long-term variations in the neutral gas composition of the thermosphere over Norilsk (2003–2013) Кушнаренко Галина Петровна Kushnarenko Galina Petrovna kusch@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Яковлева Ольга Евгеньевна Yakovleva Olga Evgenyevna yakovleva@iszf.ru Кузнецова Галина Михайловна Kuznetsova Galina Mihaylovna kuz@iszf.irk.ru Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation 23 01 2017 23 01 2017 2 4 118 125 https://zh-szf.ru/en/nauka/article/15174/view

Seasonal variations in relative values of the main gas components of the thermosphere [O]/[N2] and [O2]/[O] were obtained at the station Norilsk during the period 2003–2013. Estimates were made using a technique we devel-oped and data from the Norilsk digisonde (69° N, 88° E) for heights below the ionospheric F1-layer peak height under quiet and disturbed geomagnetic conditions in different seasons. We established that the [O2]/[O] ratio under quiet and disturbed geomagnetic conditions in all seasons by the end of 2013 decreased from 10 to 20 % relative to the values of 2003. The [O]/[N2] ratio for the same conditions increased to 17 %.

Seasonal variations in relative values of the main gas components of the thermosphere [O]/[N2] and [O2]/[O] were obtained at the station Norilsk during the period 2003–2013. Estimates were made using a technique we devel-oped and data from the Norilsk digisonde (69° N, 88° E) for heights below the ionospheric F1-layer peak height under quiet and disturbed geomagnetic conditions in different seasons. We established that the [O2]/[O] ratio under quiet and disturbed geomagnetic conditions in all seasons by the end of 2013 decreased from 10 to 20 % relative to the values of 2003. The [O]/[N2] ratio for the same conditions increased to 17 %.

 Thermospheric gas components Geomagnetic disturbances Seasonal variations Thermospheric gas components Geomagnetic disturbances Seasonal variations

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