A Study on the Variation of Total Electron Content During Geomagnetic Storm of October 2016:- The Case of High Latitude Regions

n this study We utilized GPS - based TEC data from four ground based stations: Thule, Greenland and Ny-Alesund, Norway in the Northern hemisphere, and Syogo and Palmer in the Southern Hemisphere. While earlier studies have explored storm-time TEC fluctuations caused by mechanisms such as prompt penetration Electric fields (PPEF), disturbance dynamo effects , and thermospheric composition changes, high-latitude ionospheric behaivor- particularly during this specific storm has received relatively little attention. Furthermore, important irregularities like ploar cap patches and subauroral ion drifts remain underexplored in hemispheric comparisons. This work fills a critical gap by presenting a comparative , high-resolution analysis of Vertical TEC in both hemispheres, integrating key geophysical drivers such as Polar cap index, AE(AL/AU) indices, IMF Bz, and SYM-H. Results reveal distinct hemispheric responses: VTEC peaks at ∼ 19 TECU (Thule), ∼ 10 TECU (Ny-Ålesund), ∼ 21 TECU (Syowa), and ∼ 22 TECU (Palmer), with stronger variability observed in SH stations. These differences are attributed to enhanced solar EUV exposure, hemispheric magnetic field assymetries, and intensified particle precipitation during storm-time electrodynamic conditions. By providing new insights into the dynamics of magnetosphere-ionosphere coupling during geomagnetic storms. This study contributes to a more comprehensive understanding of high-latitude space weather effects and sets the stage for future modeling and monitoring efforts.