COMPARATIVE STUDY OF EQUATORIAL PLASMA BUBBLES DURING QUIET AND STORM PERIODS

Abstract

Equatorial Plasma Bubbles (EPBs) are localized plasma density depletions that significantly affect radio wave propagation and satellite-based navigation. This study presents a comparative analysis of EPB occurrence during geomagnetically quiet and storm periods using data from ground-based GPS receivers and ionosondes over the South Asian longitudinal sector from 2010 to 2022. The investigation focuses on temporal occurrence, spatial characteristics, and the role of geophysical drivers such as the Dst and Kp indices. Results reveal a statistically significant increase in EPB activity post-sunset during storm periods, particularly influenced by prompt penetration electric fields (PPEFs) and disturbance dynamo effects. This study improves understanding of equatorial ionospheric irregularities, enhancing space weather forecasting and GNSS reliability.