Programme by Session

We use the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) to study the variability of the magnetosphere-ionosphere (MI) field-aligned currents (FACs) associated with substorms. We report on a new phenomenon that has been observed with AMPERE: the formation of an additional region 2 (R2) current, predominantly in the dusk sector. Such events are associated with substorm onset, hence we propose that this new R2 FAC is formed by plasma injections into the inner magnetosphere during the substorm expansion phase. In this talk, we focus on the interhemispheric conjugacy, or otherwise, of the observed FACs, and on the seasonal dependence of the conjugacy, for the years 2010 to 2016.