Equatorial electrojet and radio scintillations

Abstract

It is shown that the day-time scintillations of VHF radio waves at the equatorial station, Huancayo, are very small, of the order of 1-2 dB peak, during the equatorial electrojet condition. If the event of complete or partial counter-electrojet occurring either on quiet or during disturbed conditions is followed by the occurrence of blanketing type of Es, then only strong day-time scintillations are observed. Counter-electrojet events followed by only the absence of Es are not found to produce any additional scintillations. Thus the day-time VHF scintillations near the magnetic equatorial regions are due to the sharp plasma gradient associated with blanketing type of sporadic E region.