Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 113887 10.12737/stp-121202613 zggcgw Results of current research Results of current research Results of current research Probabilistic assessment of geomagnetically induced current levels based on auroral localization and structure data Probabilistic assessment of geomagnetically induced current levels based on auroral localization and structure data Воробьев Андрей Владимирович Vorobev Andrey Vladimirovich geomagnet@list.ru https://orcid.org/0000-0002-6476-9471 Соловьёв Анатолий Александрович Soloviev Anatoly Aleksandrovich rjes@wdcb.ru

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 Воробьева Гульнара Равильевна Vorobeva Gulnara Ravilevna gulnara.vorobeva@gmail.com Лапин Александр Николаевич Lapin Aleksandr Nikolaevich meccos160@yandex.ru Геофизический центр РАН Москва Россия Geophysical Center RAS Moscow Russian Federation Уфимский университет науки и технологий Уфа Россия Ufa University of Science and Technology Ufa Russian Federation Геофизический центр РАН Москва Россия Geophysical Center RAS Moscow Russian Federation Институт физики Земли им. О.Ю. Шмидта РАН Москва Россия Schmidt Institute of Physics of the Earth, RAS Moscow Russian Federation Уфимский университет науки и технологий Уфа Россия Ufa University of Science and Technology Ufa Russian Federation Уфимский университет науки и технологий Уфа Россия Ufa University of Science and Technology Ufa Russian Federation 25 03 2026 25 03 2026 12 1 114 122 05 05 2025 14 07 2025 https://zh-szf.ru/en/nauka/article/113887/view

Development of new probabilistic and statistical models for operational assessment of technospheric risks caused by space weather impacts on high-latitude power systems is a relevant research task with significant practical applications. Such models are of the greatest practical importance in polar and subpolar regions with insufficient availability of reliable and accurate geomagnetic data sources. This paper presents an original approach to hardware-free (without specialized equipment) assessment of geomagnetically induced current (GIC) levels in power systems of the Russian Arctic zone by interpreting visually observable auroral features as natural indicators of space weather conditions. Using the case study of the 330 kV Vykhodnoy substation in the Severny Transit main power grid, a stable statistical relationship is demonstrated between the auroral observation area, auroral structure, and GIC levels in high-latitude power systems. It is established that during periods of discrete auroras the probability of GIC exceeding 10 A is over 7.5 %, whereas for diffuse auroras this probability is only 0.31 %. In the absence or scarcity of instrumental measurement data, the developed models can be employed to estimate the likelihood of extreme GIC in Arctic power distribution systems and grids, relying solely on visual natural indicators. The practical application of the proposed models in certain scenarios may improve decision-making efficiency in situations with low situational awareness in the relevant field

Development of new probabilistic and statistical models for operational assessment of technospheric risks caused by space weather impacts on high-latitude power systems is a relevant research task with significant practical applications. Such models are of the greatest practical importance in polar and subpolar regions with insufficient availability of reliable and accurate geomagnetic data sources. This paper presents an original approach to hardware-free (without specialized equipment) assessment of geomagnetically induced current (GIC) levels in power systems of the Russian Arctic zone by interpreting visually observable auroral features as natural indicators of space weather conditions. Using the case study of the 330 kV Vykhodnoy substation in the Severny Transit main power grid, a stable statistical relationship is demonstrated between the auroral observation area, auroral structure, and GIC levels in high-latitude power systems. It is established that during periods of discrete auroras the probability of GIC exceeding 10 A is over 7.5 %, whereas for diffuse auroras this probability is only 0.31 %. In the absence or scarcity of instrumental measurement data, the developed models can be employed to estimate the likelihood of extreme GIC in Arctic power distribution systems and grids, relying solely on visual natural indicators. The practical application of the proposed models in certain scenarios may improve decision-making efficiency in situations with low situational awareness in the relevant field

 geomagnetic variations space weather high-latitude power grids statistical models geomagnetic variations space weather high-latitude power grids statistical models The work was financially supported by the Russian Science Foundation (Project No. 21-77-30010-P) The work was financially supported by the Russian Science Foundation (Project No. 21-77-30010-P)

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