Preliminary Results of GPS Derived Total Electron Content Variations Over Indian Antarctica Station, Maitri as Part of International Polar Year

摘要

This study investigated the behavior of high latitude ionosphere and space weather effects on it, in term of Total Electron Content (TEC), from installed Global Positioning System (GPS) over the Indian base Station Maitri (70.65⁰ N Lat, 11.45⁰ E Long) at Antarctica during the low solar activity period 2008. The study is divided into three parts namely monthly, seasonal and mid polar day and mid polar night variations. We observed that TEC values are highest during the months of January and December as compare to June month, because during January and December months, there is 24 h sun light present (Polar days) whereas in the month of June there is no sun light (Polar night). During the study of seasonal variation s, in southern winter season i.e., May, June, July and August 2008. TEC values were lowest because ionization processes are very low due to absence of sunlight and in the southern summer season TEC values reach its highest due to presence of 24 h sunlight and maximum solar radiation present at this duration. During equinoxes the study shows that in the autumnal equinox period TEC disparity is low as compare to vernal equinox period. During autumnal equinox period sun goes towards the sunset point and hence solar ionization radiations decrease day by day, whereas in the vernal equinox period it is reverse i.e., sun goes towards sunrise and it is visible for maximum duration which causes increase in ionization process and TEC value again increases.