Variation of Electromagnetic Waves, Electric Field and Magnetic Field in F region due to Earthquake

Abstract

Reliable, repeatable earthquake forecast is a subject surrounded by controversy and skepticism. What is clear is that reliable
forecast would be a critical tool for effective earthquake disaster management. It is proposed that satellites and ground-based facilities may detect earthquake precursors in the F region of Ionosphere a few hours or days before the main shock. It is proposed that, due to the anisotropy of atmospheric conductivity at heights greater than 60 km, the large-scale, high-intensity (ca. 1000 V m-1) vertical electric field appearing at seismically active regions a few days before strong earthquakes can penetrate into the ionosphere and create specific irregularities of electron concentration in this region (Pulinets et al. 1998). This anomalous quasistatic electric field generated on the ground in a seismo-active zone is detected through the seismogenic variations in the near-Earth plasma due to the high conductivity along the geomagnetic field lines. Several observations were made of Very Low Frequency (VLF) emissions 
apparently associated with earthquakes, which were recorded independently at ground-based stations and on satellites. Data were
analyzed for those cases when both intense (Ms> 5) earthquakes occurred in the region close to the satellite longitude and the satellite was operating in the VLF mode. A statistical analysis, based on the enhancement of wave intensity at the time of earthquakes and using GEOS-2 data, seems to indicate that there is a (possibly indirect) association between seismic activity and some of the VLF emissions observed at the satellite. Ionospheric measurements made from the ground also showed an increase of the critical frequencyf0Esof the sporadic layer Eswhen earthquakes occurred nearby. As, there is a change of electromagnetic waves & electric field due to earthquake in F region so, change of magnetic field should be there due to earthquake. Magnetic Field Change can be detected by satellite and the human lives and the properties can be defending from earthquake.