Solar Wind–Ionosphere–Troposphere Coupling Via the Polar Branch of the Global Electric Circuit

Abstract It is believed that the global atmospheric electrical circuit (GEC) could provide a possible link between the space environment and terrestrial weather. The electric charge from electrified clouds is uniformly distributed on the highly conductive, compared to the air below, ionospheric shell. In the polar regions, an additional, rather variable electric potential arising in the local ionosphere due to the interaction of the solar wind and the interplanetary magnetic field with the Earth's magnetosphere is superimposed on the background maintained by global thunderstorm activity. At high latitudes, variable fluxes of energetic particles of galactic, solar, and magnetospheric origin ionize atmospheric gases. This leads to an increase in the conductivity of the air. It is the polar branch of the GEC that connects the troposphere, ionosphere, magnetosphere, and the Sun. The paper is partly a review of previously published results, supplemented by an original analysis based on atmospheric electric field data collected in Antarctica. The following issues are considered: (1) fair-weather conditions and the diurnal variation in polar atmospheric electric field, (2) factors influencing the polar branch of the GEC, including the evolution of the electric potential of ionospheric convection, (3) the relationship between the ground-based potential gradient, geomagnetic variations, and other parameters; the period of March 2015, during which a magnetic storm and cyclonic activity occurred, is considered as a case study, (4) a controversial issue of the possible influence of the IMF By on the tropospheric pressure, as predicted by the Mansurov effect; the severe space weather period of October–November 2003 is taken as an example, (5) the short- and long-term periodicities in the atmospheric potential gradient.