The Results of Long-Term Observations of Electric Fields in the Atmosphere during the 2018‒2020 Eruption of Ebeko Volcano

The gradient of potential in the atmospheric electric field was recorded in the town of Severo-Kurilsk in order to study the formation of 3D electric charges in eruption clouds due to explosions during the 2018–2020 eruptions of Ebeko Volcano. A total of 179 cases were recorded in which the eruption cloud was propagating under cloudless conditions (or nearly so) accompanied by responses in the variations of electric potential in the atmosphere. Four characteristic types of response have been identified in the variations of atmospheric electric field potential. It is shown that the type of recorded response was controlled by the conditions of propagation for the eruption cloud relative to the recording site, as well as being influenced by mutual positions of the charges in the lower and upper regions of the eruption cloud at the time the response was recorded. The eruption cloud was dominated by a negative 3D electric charge localized in the upper region of the eruption cloud, while the positive 3D electric charge was localized in the lower region. The field observations are in agreement with the results of numerical simulation.