Abstract
In this paper we provide significant evidence that the sun is a principal agent provoking seismic activity. In particular the aim of the studies presented is to examine the possible relation of the coronal hole (CH) driven high speed solar wind streams (HSSs) with seismicity We performed several statistical studies of solar space and seismological data between 1980 and 2017 as well as a study for a long time interval from the year 1900 until the year 2017. (A1) Concerning the period 1980–2017 among other results we found that the earthquakes (EQs) with M ≥ 83 between 2010–2017 (including the catastrophic earthquakes of Japan 2011 (M91) Sumatra 2012 (M86) and Chile 2015 (M83)) occurred during times of large coronal holes as seen by the Solar Dynamics Observatory (SDO) satellite and were related with CH-driven HSSs observed by the ACE spacecraft several weeks or a few months before the EQ occurrences. (A2) Further research on the hypothesis of the possible HSS-EQ relationship revealed a surprising novel finding: a power spectrum analysis suggests that during the decay phase of the SCC22 and SC23 and at the maximum of SC23 the values of the global seismic (M ≥ 6) energy output shows a periodic variation of ~27 days, which is the mean rotational period of the Sun. (A3) Moderate (not strong) storms in general precede the great EQs. (B) The study of the data for the time interval 1900–2017 revealed that: (1) all of the giant (M ≥ 85) EQs occurred during the decay minimum and the rising phase of the solar cycle or in the maximum phase but at times of a strong reduction of the monthly averaged sunspot number: Chile M95 1960 EQ – Alaska M92 1964 EQ – Sumatra M91 2004 EQ (decay phase) Japan M91 2011 EQ (rising phase of the "strange" SC24) (2) the global energy release of all EQs with magnitudes M ≥ 55 show the highest values during the decay phase of the solar cycle and in particular three years after the solar maximum and (3) a very significant negative correlation (rS = −042p < 10−4) was found between the SSN and the number of earthquakes with M ≥ 7 during the period 1930–2010 during times of moderate and high amplitude solar cycles. (C) Another result of our study is that the comparison of the yearly numbers of great (M ≥ 7) EQs with the SSN fails to provide correct statistical results whereas this is possible for the global seismic energy or the giant EQs. (D) Finally we infer that the case and statistical studies presented in this paper strongly suggest a close relation between CH-associated HSSs and seismic activity. We present some observational evidence that most probably Alfvèn waves mediate the interaction of CH-driven HSSs with seismicity.
Highlights
The Sun is the principal energy source in our solar system and, the agent of many physical processes taking place in Earth’s magnetosphere [11,100,131], ionosphere [2,94], atmosphere [43,51,91], lithosphere [5,82,110] and biosphere [15,84]
Given that in our case study of the M9.1 (M9.3) Sumatra 2004 catastrophic EQ we found that the time-sifted sequences of high speed solar wind streams (HSSs) and great EQs before the giant one of December 26 [5] which occurred during the decay phase of Solar cycle 23, at a time of a large coronal hole, we wanted to examine the hypothesis that such solarspace conditions show a systematic relationship with the giant EQs and with global seismicity
The 16 giant (M ≥ 8.5) EQs which we examined in this study, as well as the peaks in the seismic energy output during the years 1900–2017 were recorded during the decay phase of the solar cycle, or at times of reduced Sunspot Number (SSN) during the maximum phase
Summary
The Sun is the principal energy source in our solar system and, the agent of many physical processes taking place in Earth’s magnetosphere [11,100,131], ionosphere [2,94], atmosphere [43,51,91], lithosphere [5,82,110] and biosphere [15,84]. In this paper we investigate, beside the 11-year cycle of the SSN, the possible relationship of the CH-driven HSSs with seismic activity, and, in particular, the possible effect of the ∼27-day mean solar rotation period on seismological data. For this reason, after a description of the instruments used in this study A variety of studies presented in this paper provide good evidence that CH-driven HSSs (most often during the decay phase of the solar cycle) make a significant contribution in provoking giant earthquakes and enhance global seismicity.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
