On the earthquake effects in the regime of ionospheric Alfvén resonances

Earthquakes can affect various parameters of the upper atmosphere above the epicenter. Ionospheric Alfvén resonances are known to be very sensitive to the state of the ionospheric layers. They are observed only for magnetically quiet conditions, so that an impact from earthquakes can easily destroy the resonance structure of waves. Starting from this consideration we searched for seismic effects in the behaviour of ionospheric Alfvén resonances using the data from a mid-latitude observational point. Our study revealed various examples of the ionospheric response to earthquake impacts. The results are given in the paper.