Prediction of Equatorial Plasma Bubble Formation Using Ionosonde Observations From India

Abstract

Prediction of equatorial plasma bubbles (EPBs) is a need of the hour for many modern navigation/communication applications. In this paper, we demonstrate an ionosonde based technique for the prediction of EPB formation overhead and its robustness using a large ionosonde data set, covering diverse solar flux and geomagnetic conditions, from three low-latitude Indian stations, namely, Trivandrum, Sriharikota and Gadanki. The technique relies on localized upwelling at the bottomside F layer, characterized by the second time derivative of the base height of the F layer observed by ionosonde, as the prime criterion deciding whether EPB will be formed overhead or not. Results show that prediction for the formation of EPB over an ionosonde station can be made with an accuracy of 99.86%. The accuracy of prediction of EPB formation over a station using data from a nearby station separated by 3.2° in longitude, however, is found to be only 83.87%, underlining the crucial role of longitudinally localized background ionospheric conditions at the bottom of the F region. We discuss the prospective of the present technique and propose a cost effective approach for developing an effective EPB prediction strategy.