Diagnostics of geomagnetically-induced currents in high-tension electric transmission lines

The problem of geomagnetically-induced currents (GIC) effect on electrotechnical systems is topical as long as uninterrupted power distribution is critically important for all the spheres of human activity. Our investigations showed the possibility of GIC diagnostics based on the estimates of industrial current higher harmonics and showed that even harmonics correlate with the Earth magnetic field changes in a greater degree. However, the measurements carried out in 220 V network showed low and not always univocal correlation of the processes. Thus, we propose a technique for diagnostics of geomagnetically-induced currents in high-tension electric transmission lines**

Complex analysis of pre-seismic geoacoustic and electromagnetic emission signals

The article describes the results of complex analysis of pre-seismic signals of electromagnetic and geoacoustic radiation. We analyzed the frequency content of single sferics and geoacoustic impulses recorded before the Zhupanov earthquake that occurred on January 30, 2016. The signals were analyzed using sparse approximation method, in particular Adaptive Matched Pursuit. Background signals were studied together with pre-seismic ones. Distributions of frequencies, that are part of background and pre-seismic signals, were compared. Differences in the frequency content of pre-seismic sferics and geoacoustic impulses were found. The revealed features of pre-seismic signals in the future can be used in the design of systems for monitoring, forecasting and prevention of natural disasters. The research was supported by Russian Science Foundation (project No. 18-11-00087)

Principles of Creation of Local Network for Lightning Discharge Observations on Active Volcanoes of Kamchatka Peninsula

To investigate the thunderstorm activity according to electromagnetic radiation recorded data, it is necessary to create a local network which will be located near the Klyuchevskaya Sopka, Shiveluch and Tolbachik volcanoes. VLF direction finders, electric field sensors, synchronization system, auxiliary equipment will be installed at observation points. Based on the analysis of waveforms and spectral-temporal characteristics, the locations of radiation sources, their belonging to a certain class will be determined. The parameters, by which volcanic lightning differs from ordinary ones, will be determined. Examples of electromagnetic radiation occurring near the Shiveluch volcano are given. The information can be further used to monitor thunderstorm and volcanic activities.*

Registration of Atmospheric-Electric Effects from Volcanic Clouds on the Kamchatka Peninsula (Russia)

The paper is devoted to the description of observations over atmospheric and electric effects from volcanic eruptions on Kamchatka peninsula (Russia) and perspectives of their development. To collect information about atmospheric-electric effects accompanying the eruptions of Kamchatka volcanoes, three sensor networks and a VLF radio direction finding station are used. The World Wide Lightning Location Network (WWLLN) provides information on high-current lightning discharges that occur during the development of an eruptive cloud (EC). Variations in the electric field of the atmosphere (AEF E z ), during the passage of EC, were obtained by a network of electric field mills at the sites for volcanic activity observations. Seismic detector network was used to make precision reference to the eruptions. Based on the data obtained, a description is given of the dynamics of eruptions of the most active volcanoes in Kamchatka and the Northern Kuril Islands (Shiveluch, Bezymianny, Ebeko). The paper presents a simulation of the response of the atmospheric electric field, which showed that the approximation by the field of distributed charges makes it possible to estimate the volume charges of EC. The fact of a multi-stage volcanic thunderstorm is confirmed. The first stage is associated with the formation of an eruptive column, and the second with the emergence, development and transfer of EC. Registration of electrical and electromagnetic processes in eruptive clouds can be one of the components of complex observations of volcanic eruptions in order to assess the ash hazard for air transport

Life-Threatening Sochi Virus Infections, Russia

Sochi virus was recently identified as a new hantavirus genotype carried by the Black Sea field mouse, Apodemus ponticus. We evaluated 62 patients in Russia with Sochi virus infection. Most clinical cases were severe, and the case-fatality rate was as high as 14.5%