Magnetic storm effects on equatorial electrojet

It is shown that the magnetic storms cause significant decrease of the electrojet current during the daytime hours at both the Indian as well as the American longitudes. In the American sectors the increase of Aurora index AE seems to be large during the decrease of the electrojet current but in the Indian sectors no such effect is seen. It is suggested that at, anti-Sq electric field is imposed at all longitudes during the magnetic storm period This causes a significantly larger decrease of Delta H at equatoria electroJet station than at off-equatorial low latitude station due to large conductivities in the equatorial ionosphere. At night hours the storm effects are same at equatorial and low latitudes due to the absence of E region ionizations and hence of the enhanced conductivities over the equator.