Irkutsk, Russian Federation
Irkutsk, Russian Federation
Irkutsk, Russian Federation
We have detected an anomalous electron density Ne increase in winter months in Irkutsk in some years of the period 2003–2014. This effect was manifested when we compared the experimental values obtained by the Irkutsk ionosonde with model calculations at F1-layer heights (120–200 km). Two anomalous time zones have been found. The first was observed in the period 2003–2006 near solar minimum. In this zone, 2003 is the year of maximum manifestation of the winter Ne increase over the entire research period. The second anomalous zone — 2012, 2013, 2014 — was detected during solar maximum. We have explored possible causes of the Ne change in winter at the F1-layer heights in all the years under study. We have found that the main factor causing the winter increase in Ne is significant geomagnetic disturbances in the above time periods.
electron density, winter increase in Ne, geomagnetic activity
1. Buresova D., Lastovicka J. Changes in the F1 region electron density during geomagnetic storms at low solar activity. J. Atmos. Solar-Terr. Phys. 2001, vol. 63, pp. 537-544. DOI:https://doi.org/10.1016/S1364-6826(00)00167-X.
2. Buresova D., Lastovicka J., Altadill D., Miro G. Daytime electron density at the F1-region in Europe during geomagnetic storms. Ann. Geophys. 2002, vol. 20, pp. 1007-1021. DOI:https://doi.org/10.5194/angeo-20-1007-2002.
3. Goncharenko L. Salah J. Crowley G., Paxton L.J., Zhang Y., Coster A., Rideout W., et al. Large variations in the thermosphere and ionosphere during minor geomagnetic disturbances in April 2002 and their association with IMF By. J. Geophys. Res. 2006, vol. 111, A03303. DOI:https://doi.org/10.1029/2004JA010683.
4. Kushnarenko G.P., Kuznetsova G.M., Yakovleva O.E. Geomagnetic storm effects at F1 layer altitudes in various periods of solar activity (Irkutsk station). Geomagnetism and Aeronomy. 2018, vol. 58, no. 2, pp. 201-206. DOI:https://doi.org/10.1134/S0016793218020135.
5. Lastovicka J. Monitoring and forecasting of ionospheric space weather effects of geomagnetic storms. J. Atmos. Solar-Terr. Phys. 2002, vol. 64, pp. 697-705. DOI:https://doi.org/10.1016/S1364-6826(02)00031-7.
6. Lastovicka J. On the role of solar and geomagnetic activity in long-term trends in the atmosphere-ionosphere system. J. Atmos Solar-Terr. Phys. 2005, vol. 67, pp. 83-92. DOI:https://doi.org/10.1016/j.jastp.2004.07.019.
7. Panasyuk M.I., Kuznetsov S.N., Lazutin L.L., Alexeev I.I., Antonova A.E., Belenkaya E.S., Bobrovnikov S.Yu., Veselovsky I.S., et al. Magnetic storms in October 2003. Cosmic Res. 2004, vol. 42, no. 5, pp. 489-534. DOI:https://doi.org/10.1023/BCOSM.0000046230.62353.61.
8. Physics of the Upper Atmosphere. Ratcliffe J.A. (ed.) London, Academic Press, 1960, 597 p.
9. 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, pp. 1469. DOI:https://doi.org/10.1029/2002JA009430.
10. Polekh N.M., Chernigovskaya M.A., Yakovleva O.E. On the formation of the F1 layer during sudden stratospheric warming. Solar-Terr. Phys. 2019, vol. 5, no. 3, pp. 117-127. DOI:https://doi.org/10.12737/stp-53201914.
11. Polyakov V.M., Shchepkin L.A., Kazimirovsky E.S., Kokourov V.D. Ionosfernye protsessy [Ionospheric processes]. Novosibirsk, Nauka Publ., 1968, 536 p. (In Russian).
12. Ratovsky K.G., Klimenko M.V., Klimenko V.V., Chirik N.V., Korenkova N.A., Kotova D.S. Geomagnetic storm aftereffects: statistical analysis and theoretical explanation. Solar-Terr. Phys. 2018, vol. 4, no. 4, pp. 26-32. DOI:https://doi.org/10.12737/stp-44201804.
13. Shchepkin L.A., Klimov N.N. Termosfera Zemli [The Earth thermosphere]. Moscow, Nauka Publ., 1980, 220 p. (In Russian).
14. 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).
15. Shchepkin L.A., Kushnarenko G.P., Kuznetsova G.M. Annual electron density variations in F1 region of ionosphere. Solnechno-zemnaya fizika [Solar-Terr. Phys]. 2005, vol. 7, pp. 62-65. (In Russian).
16. Shchepkin L.A., Kuznetsova G.M., Kushnarenko G.P., Ratovsky K.G. The interpretation of electron density measurements with using semi-empirical model. Solnechno-zemnaya fizika [Solar-Terr. Phys]. 2007, vol. 10, pp. 89-92. (In Russian).
17. Shchepkin L.A., Kuznetsova G.M., Kushnarenko G.P., Ratovsky K.G. Approximation of electron density measurements data in middle ionosphere during the low solar activity. Solnechno-zemnaya fizika [Solar-Terr. Phys]. 2008, vol. 11, pp. 66-69. (In Russian).
18. Shchepkin L.A., Kushnarenko G.P., Kuznetsova G.M. Model description of electron concentration in the middle ionosphere. Solnechno-zemnaya fizika [Solar-Terr. Phys]. 2009, vol. 13, pp. 14-18. (In Russian).
19. 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. DOI:https://doi.org/10.1023/A:1004931416167.
20. Whitten R., Poppoff I. Osnovy aeronomii [Fundamentals of Aeronomy]. Leningrad, Gydrometeoizdat Publ., 1977, 408 p. (In Russian). English edition: Whitten R.C., Poppoff I.G. Fundamentals of Aeronomy. New York, John Wiley & Sons, Inc., 1971, 462 p.
21. Yasyukevich Y., Yasyukevich A., Ratovsky K., Kli-menko M., Klimenko V., Chirik N. Winter anomaly in NmF2 and TEC: when and where it can occur. J. Space Weather Space Clim. 2018, vol. 8, no. A45. DOI:https://doi.org/10.1051/swsc/2018036.
22. URL: http//ckp-rf.ru/ckp/3056 (accessed 31 March 2021).
23. URL: http//wdc.kugi.kyoto-u.ac.jp (accessed 31 March 2021).
24. Bilitza D., Altadill D., Truhlik V., Shubin V., Galkin I., Reinisch B., Huang X. International Reference Ionosphere 2016: From ionospheric climate to real-time weather predictions. Space Weather. 2017, vol. 15, pp. 418-429. DOI:https://doi.org/10.1002/2016SW001593.
