ABSTRACT:    Fast convective transport in the plasma sheet is more prevalent in the premidnight sector relative to postmidnight. Ionospheric convection exhibits related asymmetries - more flux circulates in the dusk cell than in the dawn cell, and the nightside convection throat is rotated toward premidnight when viewed over the North Pole. I will show, using global simulations of the solar wind-magnetosphere-ionosphere interaction, that the electrodynamic interaction between Earth's magnetosphere and ionosphere produces asymmetries resembling observed distributions in plasmasheet flows and ionospheric convection. The primary causal agent in the simulations is a meridional gradient in ionospheric Hall conductance which, through Cowling polarization, regulates the distributions of i) electrical currents flowing within and between the ionosphere and magnetotail and ii) the nightside reconnection rate and resulting dawn-dusk distribution of plasma sheet fast flows. The asymmetry disappears! in the simulation when the Hall conductance is taken to be uniform, and it reverses when the conductance is artificially depleted at auroral latitudes. The asymmetry in ionospheric flux circulation in the dawn and dusk convection cells is controlled by the night-to-day gradient in Hall conductance due primarily to EUV ionization.