Радиофизика и электроника (Mar 2015)

DISTURBANCES OF LOWER IONOSPHERE ABOVE CENTER OF EARTHQUAKE AND ANOMALY IN THE GLOBAL ELECTROMAGNETIC RESONANCE SIGNAL PART 1. MODELS OF IONOSPHERE

  • A. P. Nickolaenko,
  • M. Hayakawa

DOI
https://doi.org/10.15407/rej2015.01.032
Journal volume & issue
Vol. 20, no. 1
pp. 32 – 39

Abstract

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We model an effect on the Schumann resonance signal recorded in Japan of the ionosphere non-uniformity centered above the earthquake at Taiwan. Changes in the resonance spectrum occur due to interference of the direct radio wave with one reflected from the ionosphere modification above the earthquake. The first part addresses typical models of ELF radio propagation constant and connects it with the vertical profile of atmospheric conductivity. The profile with a knee is analyzed, which is widely used for modeling the Schumann resonance. The four models are included suggested in literature for obtaining the frequency dependence of complex propagation constant of ELF radio waves. It is assumed that the pre-seismic and seismic activity locally reduces the height of the lower-boundary of the ionosphere above the earthquake. The maximum reduction reaches 20 km, and the horizontally symmetric perturbation is described by Gaussian curve having the scale of 1 000 km.

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