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Geomagnetically induced current (GIC) is determined by variations of the geomagnetic field. Predominantly geomagnetic field disturbances are oriented in the N-S direction, and produced by variations of the E-W ionospheric electrojet intensity. Thus, such disturbances seemingly do not induce any significant GIC in a N-S oriented system. However, the GIC-recording system deployed by Polar Geophysical Institute in Kola Peninsula in the electric power lines elongated in the N-S direction recorded quite significant GIC during magnetic storms and substorms. A relative contribution of geomagnetic disturbances into GIC enhancements is examined using simultaneous data from the PGI GIC-recording stations and near-by IMAGE magnetometers for several geomagnetic storms and substorms. We apply various techniques to characterize the geomagnetic field variability: the vector mapping of time series, and a measure of time variations of vector angle cosines. These techniques have shown that the equivalent ionospheric currents and GICs fluctuate not just in E-W direction, but chaotically in both E-W and N-S directions. These fluctuations cannot be described by variations of the auroral electrojet intensity only, but an adequate GIC model must take into account fast changing small-scale current systems embedded into large-scale ionospheric electrojet.