Effect of meteor ionization on sporadic-E observed at Jicamarca

Abstract

Relatively little progress has been made in the study of equatorial Sporadic-E when compared to the study of mid-latitude Sporadic-E. Indeed, it is unclear if Sporadic-E has been observed at all near the geomagnetic equator using any technique other than the ionosonde. In particular, there have been no reports of Sporadic-E observed using the Jicamarca Radio Observatory (JRO) 50 MHz radar. The overwhelming—in SNR terms—presence of the nearly ubiquitous Equatorial Electrojet (EEJ) is the likely reason Sporadic-E has not been reported at JRO as well as at other similar radars near the geomagnetic equator. We present here what we believe to be the first Sporadic-E (defined here as altitude-narrow E-region layers that last tens of minutes) observations from JRO. The structure and characteristics of these equatorial Sporadic-E layers is compared with their mid-latitude counterparts. We also demonstrate the immediate effect of meteor-produced ionization on the formation and evolution of the equatorial Sporadic-E layers.