TITLE:
Is There an Earthquake Weather?
AUTHORS:
Michel Parrot, Jean-Louis Pinçon
KEYWORDS:
Data Processing, Earthquake, Whistler, Ionosphere
JOURNAL NAME:
Open Journal of Earthquake Research,
Vol.9 No.2,
March
12,
2020
ABSTRACT: The aim of this study is to check if there is a relationship between the seismic activity and the whistlers observed by the micro-satellite DEMETER. Whistlers are the waves emitted by lightning strokes during thunderstorm activity. They use to propagate in the Earth-ionosphere waveguide but also in the ionosphere and the magnetosphere mainly along the magnetic field lines. Due to this reason we have checked the whistler occurrence not close to earthquake epicenters but close to the magnetically conjugate point of these epicenters at the satellite altitude. The number of whistlers is given by a neural network in operation onboard the satellite. It appears that the whistler amplitude is attenuated at the satellite altitude around the magnetic equator. It is why we have removed the earthquakes occurring at low geomagnetic latitudes in the statistic. The whistler rate is normalized with a background value to take into account the seasons and the epicenter locations. A superposed epoch method is used to display the results between -15 and +5 days around the earthquake day and up to 1000 km from the conjugate point of the epicenters. It is shown that the whistler rate is higher the day before the earthquake at a distance less than 200 km. It would be unrealistic to believe in the possibility to use this study for earthquake prediction because everyday thunderstorm activity reliably masks seismic effects. But it is further evidence that there is a lithosphere-atmosphere-ionosphere coupling at the time of the seismic activity.