• Vladimir A. Srećković University of Belgrade, Institute of Physics, Belgrade
  • Desanka M. Šulić Union — Nikola Tesla University, Belgrade
  • Veljko Vujčić University of Belgrade, Faculty of Organizational Sciences, Belgrade; Astronomical Observatory, Belgrade
  • Darko Jevremović Astronomical Observatory, Belgrade
  • Yaroslav Vyklyuk Bukovinian University, Department of Computer Systems and Technologies, Chernivtsi



solar activity, solar flares, terrestrial atmosphere, electron density


Solar flare X-ray energy can cause strong enhancements of the electron density in the Earth’s atmosphere. This intense solar radiation and activity can cause sudden ionospheric disturbances (SIDs) and further create ground telecommunication interferences, blackouts as well as some natural disasters and caused considerable material damage. The focus of this contribution is on the study of these changes induced by solar X-ray flares using narrowband Very Low Frequency (VLF, 3–30 kHz) and Low Frequency (LF, 30–300 kHz) radio signal analysis. The model computation and simulation were applied to acquire the electron density enhancement induced by intense solar radiation. The obtained results confirmed the successful use of applied technique for detecting space weather phenomena such as solar explosive events as well for describing and modeling the ionospheric electron density which are important as the part of electric terrestrial-conductor environment through which external-solar wind (SW) electrons can pass and cause natural disasters on the ground like fires.

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How to Cite

Srećković, V. A., Šulić, D. M., Vujčić, V., Jevremović, D., & Vyklyuk, Y. (2017). THE EFFECTS OF SOLAR ACTIVITY: ELECTRONS IN THE TERRESTRIAL LOWER IONOSPHERE. Journal of the Geographical Institute “Jovan Cvijić” SASA, 67(3), 221–233.