Variations of geomagnetic H, D, and Z field intensities on quiet days at west african latitudes

Abstract

In the framework of the French participation to the International Equatorial Electrojet Year (IEEY), a network of ten electro-magnetic stations was installed at African latitudes. These stations measured digitally the three components of the magnetic field and the two components of the telluric electric field, and operated over a period of 20 months. The magnetic data are used to study the variations of geomagnetic H, D, and Z field intensities on quiet days. Night-time variations in all the three geomagnetic elements were observed, which suggests there is a night-time current in the West African dip equatorial latitudes. The pattern of variations observed in H element, which peaks around noon, is seen to be due to the equatorial electrojet current. A reverse current called the counter electrojet current was noticed on some days.