On Geoseismic Noise and Helioseismic Oscillations

Abstract—In their paper published in Izvestiya, Physics of the Solid Earth, G.A. Sobolev et al. (2020) discussed the results of their study. Firstly, it is noted that the most important element of the magnetic storm affecting seismicity is the Pc5 geomagnetic pulsations. In the context of magnetohydrodynamics, Pc5 are interpreted as standing Alfvén waves. It is perhaps the Alfvén waves that induce oscillations recorded by the authors of the cited paper. Secondly, it is hypothesized that the Pc5 spectrum is contributed by solar 5-min oscillations known in helioseismology. Thus, it is likely that there is yet another channel through which the Sun may affect the Earth and, inter alia, the Earth’s seismicity. Special focus is placed on the question of instrumental noise.