The σyy model for the equatorial electrojet presented earlier is revised by including a meridional current system, thus making the current density divergence‐free. Using a spherical harmonic expansion for the geomagnetic field, a model electrojet is constructed for each of the longitudes of 0°, 40°, 80°, 180°, and 280°E. It is shown that the essential feature of the meridional current system is the existence of two current loops, one on each side of the dip equator and with an equatorward current in the lower E region, an upward current over the dip equator, and a return current flowing in the upper E region. The intensities of the electrojet and the associated meridional current are significantly dependent on longitude, being strongest over Peru and weakest over India. The new model predicts a reversed (westward) current in a thin, narrow layer located at several degrees off the dip equator, which is due to a reversal of the vertical polarization field. The meridional current loop creates a toroidal magnetic field of an intensity comparable with that of the main electrojet.

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The existence of highly correlated quasi‐biennial variations in the geomagnetic field and in solar activity is demonstrated. The analysis uses a numerical filter technique applied to monthly averages of the geomagnetic horizontal component and of the Zurich relative sunspot number. Striking correlations are found between the quasi‐biennial geomagnetic variations determined from several magnetic observatories located at widely different longitudes, indicating the worldwide nature of the obtained variation. The correlation coefficient between the filtered Dst index and the filtered relative sunspot number is found to be –0.79 at confidence level >99% with a time lag of 4 months, solar activity preceding the Dst variation. The correlation between the unfiltered data of Dst and those of the sunspot number is also high with a similar time lag. Such a time lag has not been discussed in the literature, and a further study is required to establish the mode of sun‐earth relationship that gives this time delay.

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