We report the initial results of the statistical analysis of field-aligned currents FACs observed above the ionosphere by the~low-Earth polar-orbiting Swarm satellite. FACs are the main electrodynamic agent of the solar wind-magnetosphere-ionosphere coupling. FACs flow along the high-conducting geomagnetic field lines between the magnetospheric boundary layers and the auroral ionosphere. A series of the~Swarm-based statistical maps of large-scale FACs~are constructed, resolving the seasonal dependences of the FAC distribution under conditions of the northward and southward interplanetary magnetic field IMF, low solar activity and the total IMF strength of 1-2~nT on average. The conventional R0/R1/R2 system is the dominant feature in the dark and sunlit polar ionosphere. The upward/downward current densities are well balanced within a given hemisphere, demonstrating a reasonable rate of elevation, going from winter to summer and from positive to negative IMF. The FAC intensities are larger by a factor of 1.6 in the summer hemisphere in comparison to the winter hemisphere.
solar wind-magnetosphere-ionosphere interaction, field-aligned currents, statistical maps, Swarm satellites
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