Meridional Currents of the Equatorial Electrojet

Abstract The equatorial electrojet (EEJ) is a prominent eastward geomagnetic current flowing at the dayside magnetic dip equator, peaking just before noon. Associated meridional currents also flow perpendicular to the main current, predicted through modeling and observed in rocket measurements. While these currents help explain some of the observed intensity of the EEJ, any further relationship between the two currents is poorly understood. This research proposes that the intensification of the EEJ is at least partially due to this meridional current system. To explore this hypothesis, data from several ground magnetic stations near the dip equator in Southeast Asia was analyzed. Principal component analysis was used to isolate the signature of the proposed meridional current structure. The analysis revealed a signal corresponding to the proposed meridional current structure that was also linked to the intensification of the EEJ. Future efforts will focus on elucidating mechanisms for the observed current system.