Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 29515 10.12737/stp-52201916 Results of current research Results of current research Results of current research Geomagnetic disturbances at F1-layer heights under different solar activity conditions over Norilsk Geomagnetic disturbances at F1-layer heights under different solar activity conditions over Norilsk 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 5 2 113 115 https://naukaru.ru/en/nauka/article/29515/view

We analyze the influence of geomagnetic disturbances on the electron density Ne at Norilsk ionospheric station (69° N; 88° E) at F1-layer heights (120–200 km). For the analysis, we have selected 25 moderate and weak geomagnetic disturbances for two seasons — spring and fall — of 2003–2014. Using the Ne values obtained from measurements made with the Norilsk digisonde during this period, we analyze Ne variations during geomagnetic disturbances in spring and fall for a long period of time. We determine the effect of spring-fall asymmetry occurring in all solar activity phases and manifesting itself in a significant decrease in the electron density during the main phase of fall storms at all heights in comparison with quiet days: up to 2.6 times at a height of 200 km and slightly less at lower heights. This phenomenon is not observed during spring disturbances: Ne variations are much weaker.

We analyze the influence of geomagnetic disturbances on the electron density Ne at Norilsk ionospheric station (69° N; 88° E) at F1-layer heights (120–200 km). For the analysis, we have selected 25 moderate and weak geomagnetic disturbances for two seasons — spring and fall — of 2003–2014. Using the Ne values obtained from measurements made with the Norilsk digisonde during this period, we analyze Ne variations during geomagnetic disturbances in spring and fall for a long period of time. We determine the effect of spring-fall asymmetry occurring in all solar activity phases and manifesting itself in a significant decrease in the electron density during the main phase of fall storms at all heights in comparison with quiet days: up to 2.6 times at a height of 200 km and slightly less at lower heights. This phenomenon is not observed during spring disturbances: Ne variations are much weaker.

 geomagnetic disturbances electron density spring-fall asymmetry geomagnetic disturbances electron density spring-fall asymmetry

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