The analyzes show that the correlation maximum occurs every 10 or 11 years, a period similar to the solar activity cycle.
There is a clear statistical correlation between global seismic activity and changes in the intensity of cosmic radiation recorded on the surface of our planet, which could help predict earthquakes. Surprisingly, it exhibits a periodicity that evades unequivocal physical interpretation. Strong earthquakes usually cause many human casualties and enormous material losses. The scale of the tragedy could be significantly reduced if we had the ability to predict the time and place of such catastrophic events. The CREDO project, started in 2016 by the Institute of Nuclear Physics of the Polish Academy of Sciences (FIP PAN) in Krakow, attempts to verify the previously known hypothesis that earthquakes could potentially be predicted by observing changes in… cosmic radiation. Statistical analyzes have shown that there is a correlation between the two phenomena, but it manifests characteristics that no one expected.
The international project CREDO (Cosmic Ray Extremely Distributed Observatory) is a virtual cosmic ray observatory, open to all, that collects and processes data not only from sophisticated scientific detectors, but also from a large number of smaller detectors, including find CMOS sensors in smartphones are leading the way (to turn a smartphone into a cosmic ray detector, just install the free CREDO Detector app).
One of CREDO’s main tasks is to monitor global changes in the flux of secondary cosmic radiation reaching the surface of our planet. This radiation is produced in the Earth’s stratosphere with greater intensity within the so-called Regener-Pfotzer maximum, where primary cosmic radiation particles collide with gas molecules in our atmosphere and initiate cascades of secondary particles. “At first glance, the idea that there is a link between earthquakes and cosmic radiation, in its primary form that comes to us mainly from the sun and deep space, may seem strange. However, its physical foundations are completely rational”, says Dr. Piotr. Homola (IFJ PAN and AstroCeNT CAMK PAN), CREDO coordinator and first author of the paper describing the discovery in the Journal of Atmospheric and Solar-Terrestrial Physics. The main idea here is the observation that eddy currents in our planet’s liquid core are responsible for generating Earth’s magnetic field. This field deflects the paths of charged particles of primary cosmic radiation. Thus, if large earthquakes were associated with perturbations in the flows of matter that drive the Earth’s dynamo, these perturbations would alter the magnetic field, which in turn would affect the trajectories of primary cosmic radiation particles in a way that depends on the dynamics of disturbances inside our planet.
CREDO physicists analyzed cosmic ray intensity data from two stations of the Neutron Monitor Database project (collected over the last half century) and the Pierre Auger Observatory (collected since 2005). The choice of observatories was determined by the fact that they are located on both sides of the equator and use different detection techniques. The analyzes included changes in solar activity, as described in the database maintained by the Solar Influences Data Analysis Center. Key information on Earth’s seismic activity was obtained in turn from the United States Geological Survey program. Analyzes were carried out using various statistical techniques. In each case, for the period studied, a clear correlation emerged between the changes in the intensity of secondary cosmic radiation and the sum of the magnitude of all earthquakes with magnitudes greater than or equal to 4. It is important to note that this correlation was only becomes apparent when the cosmic ray data is shifted 15 days forward relative to the seismic data. This is good news, as it suggests the possibility of detecting upcoming earthquakes well in advance. Unfortunately, it is not clear from the analyzes whether it will be possible to identify the locations of the cataclysms. Correlations between changes in cosmic ray intensity and earthquakes are not apparent in location-specific analyses. They only appear when seismic activity on a global scale is taken into account. This fact may mean that in the intensity changes of cosmic rays one can see a phenomenon to which our planet as a whole is subjected.
“In the scientific world, it is accepted that a discovery can be said to have been made when the statistical confidence level of the corroborating data reaches five sigma, or standard deviations. For the observed correlation, we got more than six sigma, which means less than a one in a trillion chance that the correlation is due to chance. Therefore, we have a very good statistical basis for stating that we have discovered a truly existing phenomenon. The only question is, is it really the one we expected? wonders Dr. Homola. Indeed, it turns out that the global nature of the observed phenomenon and the 15-day advance in seismic activity evident in cosmic radiation are not the only intriguing puzzles associated with the discovery. One big surprise is the large-scale periodicity of the correlation, a phenomenon that no one expected. The analyzes show that the correlation maximum occurs every 10 or 11 years, a period similar to the solar activity cycle. However, it does not coincide at all with the maximum activity of our star. In addition, there are other common periodicities of an unknown nature in both seismic and cosmic ray data. Examples include periodic changes in seismic activity and cosmic secondary radiation intensity during a cycle corresponding to Earth’s stellar day (equal to 24 hours minus ~236 seconds). Is it then that the cosmic-seismic correlations are caused by some factor that reaches us from outside the solar system, capable of simultaneously producing radiation and seismic effects? What conventional physical phenomenon alone could even qualitatively explain the apparent correlations?
The lack of classical explanations for the observed periodicities prompts consideration of the possible role of other less conventional phenomena. One of them could be the passage of the Earth through a stream of dark matter modulated by the sun and other massive bodies in our planetary system. Earth, with its large magnetic field, is an extremely sensitive particle detector, many times larger than detectors built by humans. Therefore, it is reasonable to allow the possibility that it may respond to phenomena that are invisible to existing measurement devices.