Abstract Equatorial electrojet (EEJ) and solar quiet (Sq) currents with one vortex each in either hemisphere are key components of the ionospheric dynamo currents, driving geomagnetic diurnal variations observed at Earth’s surface. However, the physical coupling between EEJ and Sq westward currents on the polar side of the vortex focus remains poorly understood. Here, we present observational evidence that there are significant correlations between EEJ variability and Sq westward currents variability in both morning and afternoon sectors, with correlation coefficients of −0.87 during March in the afternoon and −0.67 during May in the morning, respectively. The seasonal variations of the correlations exhibit a morning‐afternoon asymmetry. Specifically, the correlations in the afternoon are stronger during the hemispheric summer season, whereas in the morning correlations show a slightly semiannual variation that are stronger approximately during the equinoxes. The results are helpful for understanding of current closure and global ionospheric electrodynamics.

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