Long term ionospheric TEC variation over high latitude region during 24th solar cycle

Abstract

The long term variation of Ionospheric Total electron content (ITEC) has been examined over high latitude region during inclination phase of 24th solar cycle and it has been observed that solar cycle, seasonal and geomagnetic activity has a prominent effect on ITEC. The ITEC data has been acquired with the help of Novatel make Global Ionospheric Scintillation and TEC monitoring (GISTM) system installed at Indian permanent scientific base “Maitri” [70°46'00”S 11°43’56” E], Antarctica. To investigate the vulnerability of Vertical Total Electron Content (VTEC) upon the sunspot numbers (SSN), linear and quadratic regression method has been used and it has been found that quadratic relation grant better correlation between VTEC and SSN. Further, during the investigation of ITEC seasonal variation, it is watched that VTEC and SSN follows better agreement during summer seasons as compared to winter and equinox seasons. However, an extraordniray agrrement has been noticed during the solar minimum phase (2010). Meanwhile, during the study of quiet days throughout the considered time frame i.e. 2010 to 2014, an improved correlation has been found between VTEC and SSN. During the long term study of ITEC, a saturation effect has been also observed during maximum phase (2014) of the 24th solar cycle.