This review, offered for the first time in the Russian scientific literature, is devoted to various aspects of the problem of the space weather impact on ground-based technological systems. Particular attention is paid to hazards to operation of power transmission lines, railway automation, and pipelines caused by geomagnetically induced currents (GIC) during geomagnetic disturbances. The review provides information on the main characteristics of geomagnetic field variability, on rapid field variations during various space weather mani-festations. The fundamentals of modeling geoelectric field disturbances based on magnetotelluric sounding algorithms are presented. The approaches to the assessment of possible extreme values of GIC are considered. Information about economic effects of space weather and GIC is collected. The current state and prospects of space weather forecasting, risk assessment for technological systems from GIC impact are discussed. While in space geophysics various models for predicting the intensity of magnetic storms and their related geomagnetic disturbances from observations of the interplanetary medium are being actively developed, these models cannot be directly used to predict the intensity and position of GIC since the description of the geomagnetic field variability requires the development of additional models. Revealing the fine structure of fast geomagnetic variations during storms and substorms and their induced GIC bursts appeared to be important not only from a practical point of view, but also for the development of fundamentals of near-Earth space dynamics. Unlike highly specialized papers on geophysical aspects of geomagnetic variations and engineering aspects of the GIC impact on operation of industrial transformers, the review is designed for a wider scientific and technical audience without sacrificing the scientific level of presentation. In other words, the geophysical part of the review is written for engineers, and the engineering part is written for geophysicists. Despite the evident applied orientation of the studies under consideration, they are not limited to purely engineering application of space geophysics results to the calculation of possible risks for technological systems, but also pose a number of fundamental scientific problems
Extreme Space Weather Impact: An Emergency Management Perspective