Scattering of VHF transmitter signals by seismic-related electric discharges in the troposphere

• VHF electromagnetic wave is scattered on the random discharges in the troposphere.
• Electric discharges caused by disturbances of electric current.
• Current disturbances are occurred by charged aerosols injection during seismicity.
• Scattered wave significant exceeds the field of diffracted wave over horizon.

The scattering of VHF electromagnetic waves by random electric discharges occurring in the troposphere over a seismic region has been considered, which are caused by the disturbances of electric current in the global atmosphere–ionosphere circuit. Current disturbances are connected with the injection of charged aerosols as a result of the lifting of soil gases during earthquake preparation. It is shown that the electric field of disturbed current can reach a breakdown value at the altitudes 5–10 km. The method for calculating the mean value of electromagnetic wave fields scattered by the random discharges has been elaborated, which show that the electric field of scattered wave exceeds significantly that of diffracted wave over the horizon. The results of our theory are confirmed by the observational data of VHF transmitter signals over the horizon during earthquake preparation.