Alma-Ata, Kazakhstan
Alma-Ata, Kazakhstan
Alma-Ata, Kazakhstan
The paper presents the results of a study of the behavior of ionospheric parameters of the total electron content, I(t), and electron density in the maximum F2 layer, Nm, over Almaty (Kazakhstan) [43.25° N; 76.92° E] in 1999–2013. The time interval under study covers different solar activity levels. We have shown that at F10.7>175 in summer and at F10.7>225 in winter there is a saturation effect, i.e. with increasing solar activity level values of I(t) do not increase. The observed nonlinear relationship between the total electron content of the ionosphere and the solar radiation flux F10.7 results from the nonlinear relationship between the solar ultraviolet radiation and the solar radiation flux. The study of the variability of the mid-latitude ionosphere parameters during different solar and geomagnetic activity levels has shown that the standard deviation ç(x) and average shift Xave of I(t) and Nm fluctuations relative to the quiet level weakly depend on solar activity, but greatly depend on geomagnetic activity when F10.7<100.
total electron content, solar activity, ionosphere
1. Afraimovich E.L., Perevalova N.P. GPS-monitoring verkhnei atmosfery Zemli [GPS-Monitoring of the Upper Atmosphere of the Earth]. Irkutsk, ISTP SB RAS, 2006, 480 p. (In Russian).
2. Araujo-Pradere E.A., Fuller-Rowell T.J., Codrescu M.V., Bilitza D. Characteristics of the ionospheric variability as a function of season, latitude, local time, and geomagnetic ac¬tivity. Radio Sci. 2005, vol. 40, RS5009. DOI: 10.1029/ 2004RS003179.
3. Balan N., Bailey G.J., Jayachandran B. Ionospheric evi¬dence for a nonlinear relationship between the solar e.u.v. and 10.7 cm fluxes during an intense solar cycle. Planet. Space Sci. 1993, vol. 41, no. 2, pp. 141-145. DOI:https://doi.org/10.1016/0032-0633(93)90043-2.
4. Bolaji O.S., Adebiyi S.J., Fashae J.B. Characterization of ionospheric irregularities at different longitudes during quiet and disturbed geomagnetic conditions. Atmos. Solar-Terr. Phys. 2019. vol. 182, pp. 93-100. DOI:https://doi.org/10.1016/j.jastp. 2018.11.007.
5. Bruevich E.A., Bruevich V.V., Yakunina G.V. Cyclic variations in the solar radiation fluxes at the beginning of the 21st century. Moscow University Physics Bulletin. 2018, vol. 72, no. 2, pp. 216-222.
6. Deminov M.G., Deminova G.F., Zherebtsov G.A., Pirog O.M., Polekh N.M. Variability of parameters of the F2-layer maximum in the quiet midlatitude ionosphere under low solar activity: 1. Sta¬tistical properties. Geomagnetism and Aeronomy. 2011, vol. 51, no. 3, pp. 348-355. DOI: 10.1134/ S0016793211020058.
7. Deminov M.G., Deminova G.F., Zherebtsov G.A., Polekh N.M. Properties of the F2-layer maximum density variability over Irkutsk under different levels of the solar and geomag¬netic activity. Solar-Terrestrial Physics. 2015, vol. 1, no. 1, rr. 56-62. DOI:https://doi.org/10.12737/6558. (In Russian).
8. Essex E.A., Klobuchar J.A. Mid-latitude nighttime in¬creases in the total electron content of the ionosphere. J. Geophys. Res. 1980, vol. 85, no. A11, pp. 6011-6020. DOI: 10.1029/ JA085iA11p06011.
9. Gulyaeva T.L. Modification of solar activity indices in the International Reference Ionosphere IRI and IRI-Plas models due to recent revision of sunspot number time series. Solar-Terrestrial Physics. 2016, vol. 2, no. 3, rr. 87-98. DOI:https://doi.org/10.12737/22287.
10. Ishkov V.N. Tekushchii 24 tsikl solnechnoi aktivnosti: evolyutsiya, osobennosti, aktivnye yavleniya, prognoz razvitiya [The current 24th cycle of solar activity: evolution, characteristics, active phenomena, development forecast]. Polar 2012. http://www.izmiran.ru/POLAR2012/REPORTS/POLAR_ 212_Ischkov.pdf (accessed 13 May 2019).
11. Mandrikova O., Polozov Y., Fetisova N., Zalyaev T. Analysis of the dynamics of ionospheric parameters during periods of increased solar activity and magnetic storms. J. Atmos. Solar-Terr. Phys. 2018, vol. 181, pp. 116-126. DOI:https://doi.org/10.1016/j.jastp. 2018.10.019.
12. Mannucci A.J., Wilson B.D., Yuan D.N., Ho C.H., Lindqwister U.J., Runge T.F. A global mapping technique for GPS-derived ionosphere TEC meas¬urements. Radio Sci. 1998, vol. 33, no. 3, pp. 565-582. DOI:https://doi.org/10.1029/97RS02707.
13. Mukasheva S.N. Morfologiya povedeniya integral'nogo elektronnogo soderzhaniya ionosfery nad Kazakhstanom (po dannym transionosfernogo zondirovaniya). Dis. … kand. fiz.-mat. nauk [Morphology of the behavior of the integrated elec¬tron content of the ionosphere over Kazakhstan (according to TRANS-ionospheric sounding) Dr. phys. and math. sci. diss.]. Almaty, 1999, 120 p. (In Russian).
14. Schaer S., Beutler G., Rothacher M. Mapping and pre¬dicting the ionosphere. Proc. of the IGS AC. Workshop. Darmstadt, Germany. February 9-11. 1998a, pp. 307-320.
15. Schaer S., Gurtner W., Feltens J. IONEX: The Ionosphere Map Exchange Format Version1. Proc. of the IGS AC. Workshop. Darmstadt, Germany. February 9-11. 1998b, pp. 233-247.
16. Shi H., Zhang D., Liu Y., Hao Y. Analysis of the iono¬spheric variability based on wavelet decomposition. Sci. China Tech. Sci. 2014, vol. 58, iss. 1, pp. 174-180. DOI: 10.1007/ s11431-014-5709-8.
17. Shreedevi P.R., Choudhary R.K., Yadav S., Thampi S.V., Ajesh A. Varia¬tion of the TEC at a dip equatorial station, Trivandrum and a mid latitude station, Hanle during the descending phase of the solar cycle 24(2014-2016). J. Atmos. Solar-Terr. Phys. 2018, vol. 179, pp. 425-434. DOI:https://doi.org/10.1016/j.jastp. 2018.09.010.
18. Titheridge J.E. The electron content of the southern mid-latitude ionsphere, 1965-1971. J. Atmos. Solar-Terr. Phys. 1973, vol. 35, pp. 981-1001. DOI:https://doi.org/10.1016/0021-9169(73) 90077-9.
19. Tobiska W.K. Revised solar extreme ultraviolet flux model. J. Atmos. Solar-Terr. Phys. 1991, vol. 53, pp. 1005-1018. DOI:https://doi.org/10.1016/0021-9169(91)90046-A.
20. URL: http://www.swpc.noaa.gov (accessed May 20, 2019).
21. URL: ftp://cddis.gsfc.nasa.gov/pub/gps/products/ionex (accessed May 20, 2019).
