Daytime F Region Echoes at Equatorial Ionization Anomaly Crest during Geomagnetic Quiet Period: Observations from Multi-Instruments

Overview & Synopsis

F region echoes associated with small-scale irregularity are generally observed during nighttime by VHF radar. During daytime, some cases of F region echoes were reported for the past several decades. The possible reason of the daytime F region echoes generation is still unclear. By using Qujing VHF radar, we observed daytime F region echo phenomena at equatorial ionization anomaly crest. Simultaneous observations of ionospheric disturbance and atmospheric gravity wave activities revealed that daytime F region echoes could be excited by ionospheric disturbance during the strong atmospheric gravity wave activities. Our results provided the observational evidence of links among different ionospheric disturbance in the daytime region of China.