Иркутск, Россия
Иркутск, Россия
Иркутск, Россия
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
1. Belov A.V., Gaidash S.P. Anomalously low solar and geomagnetic activities in 2007. Geomagnetizm i aeronomiya [Geomagnetism and Aeronomy]. 2009, vol. 49, no. 5, pp. 595-602. (In Russian).
2. Emmert J.T., Lean J.L., Picone J.M. Record low thermospheric density during the 2008 solar minimum. Geophys. Res. Lett. 2010, vol. 37, L12102. DOI:https://doi.org/10.1029/2010GL043671.
3. Hedin A.E. MSIS-86 thermospheric model. J. Geophys. Res. 1987, vol. 92, no. A5, pp. 4649-4662.
4. Kushnarenko G.P., Kuznetsova G.M., Kolpakova O.E. Estimations of ratios of dominant gas components during strong and moderate geomagnetic disturbances in periods of solar activity decay and minimum. Solnechno-zemnaya fizika [Solar-Terrestrial Physics]. 2011, iss. 19, pp. 134-139. (In Russian).
5. Kushnarenko G.P., Yakovleva O.E., Kuznetsova G.M. Seasonal variations in ratios of main gas components of thermosphere in the solar activity last minimum (2007-2009). Solnechno-zemnaya fizika [Solar-Terrestrial Physics]. 2014, iss. 25, pp. 29-32. (In Russian).
6. Kushnarenko G.P., Yakovleva O.E., Kuznetsova G.M. Long-term variations in the neutral gas composition of the termosphere above Norilsk (2003-2013 гг.). Solnechno-zemnaya fizika [Solar-Terrestrial Physics]. 2016, vol. 2, no. 4, pp. 118-125. DOI:https://doi.org/10.12737/24278.
7. Picone J.M., Hedin A.E., Drob D.P., Aikin A.C. (GTD7-2000) NRLMSISE-00 Empirical model of the atmosphere: statistical comparisons and scientific issues. J. Geophys. Res. 2002, vol. 107, no. A12, p. 1469. DOI:https://doi.org/10.1029/2002JA009430.
8. Shchepkin L.A., Kushnarenko G.P., Freizon I.A., Kuznetsova G.M. The electron density connection with the thermospheric state in the middle ionosphere. Geomagnetizm i aeronomiya [Geomagnetism and Aeronomy]. 1997, vol. 37, no. 5, pp. 106-113. (In Russian).
9. Solomon S.C., Woods T.N., Didkovsky L.V., Emmert J.T., Qian L. Anomalously low solar extreme ultraviolet irradiance and thermospheric density during solar minimum. Geophys. Res. Lett. 2010, vol. 37, L16103. DOI:https://doi.org/10.1029/2010GL044468.
10. Tobiska W.K., Eparvier F.G. EUV97: Improvements to EUV irradiance modeling in the soft X-rays and EUV. Solar Phys. 1998, vol. 147, no. 1, pp. 147-159.
11. Yakovleva O.E., Kushnarenko G.P., Kuznetsova G.M. The main gas components of the thermosphere [O]/[N2] and [O2]/[O] in the years of minimum solar activity (2007-2009) at the station Norilsk. Trudy Mezhdunarodnoi Baykalskoi molodezhnoi nauchnoi shkoly po fundamentalnoi fizike i konferentsii molodykh uchenykh “Vzaimodeystvie poley i izlucheniya s veshchestvom” [Proceedings of Baikal Young Scientist’s International School on Fundamental Physics and Young Scientist’s Conference “Interaction of Fields and Radiation with Matter”]. Irkutsk, 2015, рр. 209-211. (In Russian).
12. URL: http://ckp-rf.ru/ckp/3056 (accessed at January 31, 2020).
13. URL: http://guvitimed.jhuapl.edu (accessed at January 31, 2020).
14. URL: http://wdc.kugi.kyoto-u.ac.jp (accessed at January 31, 2020).