Climatology of Nighttime Equatorial Electrojet radar echoes at Jicamarca

The Equatorial Electrojet (EEJ) is a strong current of charged particles that circulates the Earth along the magnetic equator at E-region heights. Backscattered radar signals coming from plasma irregularities generated by the EEJ are measured routinely with the Jicamarca 50-MHz radar. Although numerous studies regarding the diurnal climatology of these echoes have been conducted[1,2] there is a notable lack of studies concerning their nighttime behavior.To address this gap, a statistical study of the occurrence and variation of the Nighttime Equatorial Electrojet radar echoes have been conducted. For this purpose, we have estimated he monthly averaged zonal and vertical drifts over Jicamarca as a function of local time, altitude, and season for years corresponding to different levels of solar activity (solar cycles 23 and 24). These metrics provide valuable insights into the typical behavior of EEJ echoes during nighttime.