Observations and model computations are compared of the Umov – Poynting vector (UPV) in the Schumann resonance (SR) band during the eruption of Tonga volcano on Jan. 15, 2022. The volcanogenic SR signals were recorded at the dual site: at the Cumiana observatory (44.96° N and 7.42° E) in the vertical electric field component and at the Sos Enattosobservatory (40.47° N, 9.48° E) in the two orthogonal ELF components of horizontal magnetic field. Initially, we present computations in the update model of the Earth – ionosphere cavity with the global lightning stroke distribution found by the Worldwide Lightning Location Network (WWLLN), which demonstrates the workability of our approach. The hodographs of UPV were obtained in the frequency (formally rigorous) and the time domain during the major phase of eruption. The positions of both of them suitably agree with each other and indicate on the wave arrival from the compact area around volcano during the major phase of Tonga eruption. The UPV magnitude indicates that the contribution from the Tonga volcano has elevated the observed level of ELF power flux by the factor of six relative to the quiet condition.
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