Observational and Model Impact of Tonga Volcano Eruption on Schumann Resonance

Abstract

Tonga volcano eruption on 15 January 2022 was accompanied by an unprecedentedly high lightning activity in the volcano plume which significantly exceeded the lightning activity level of the whole globe. We compare model computations with the observed effect of the Tonga volcano eruption on the global electromagnetic Schumann resonance (SR). This SR disturbance was detected at many observatories covering the whole globe. SR power spectral density was computed using the updated model of the Earth-ionosphere cavity, with the global lightning detections recorded by the World Wide Lightning Location Network, as a source. The modeled dynamics of the SR disturbances during Tonga eruption agrees qualitatively and quantitatively with SR recordings from six globally separated observatories. Unprecedentedly high lightning activity during the active phase of eruption caused significant suppression of the global lightning detection rate without noticeable effect on real global thunderstorm activity.