COMPARATIVE STUDY OF IONOSPHERIC SCINTILLATIONS ACROSS LOW AND MID-LATITUDES

Abstract

Ionospheric scintillations—rapid fluctuations in the amplitude and phase of trans-ionospheric radio signals—pose significant threats to communication and navigation systems, particularly those relying on GNSS technologies. These phenomena are strongly influenced by geomagnetic latitude, local time, season, and solar activity. This study presents a comparative analysis of ionospheric scintillation characteristics across low- and mid-latitude regions, focusing on Pakistan and adjacent countries. Scintillation data collected from GNSS receivers in Karachi (low-latitude), Islamabad (transition zone), and Gilgit (mid-latitude) from 2010 to 2023 were analyzed. Key parameters such as the S4 index and phase scintillation index (σϕ) were examined alongside TEC and geomagnetic indices. The results demonstrate distinct seasonal, diurnal, and storm-time patterns in both latitudinal domains, with low-latitude stations showing intense post-sunset scintillations and mid-latitude stations exhibiting sporadic events during geomagnetic storms. Understanding these latitudinal dependencies enhances our capability to mitigate GNSS signal degradation in operational systems.