Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 46568 10.2205/2020ES000749 ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Variability of ionospheric TEC at low latitude station,Hyderabad during medium solar activity Variability of ionospheric TEC at low latitude station,Hyderabad during medium solar activity Bhardwaj Shivangi Bhardwaj Shivangi Khan Parvaiz A Khan Parvaiz A Manssori Azad A Manssori Azad A azadahmad199@gmail.com Ahmad Rafi Ahmad Rafi Purohit P K Purohit P K Sri Sai University ru Sri Sai University ru Govt. Degree College for Women ru Govt. Degree College for Women ru Govt. P. G. College ru Govt. P. G. College ru National Institute of Technical Teachers’ Training and Research ru National Institute of Technical Teachers’ Training and Research ru National Institute of Technical Teachers’ Training and Research ru National Institute of Technical Teachers’ Training and Research ru 21 2 29 10 2021 https://ras.editorum.ru/en/nauka/article/46568/view

The successful operation of communicational and navigational applications requires knowledgeof state and behaviour of ionosphere as well as spatial and temporal changes taking place init. With this view, we have studied the variability and changes in the low latitude ionosphereby considering a low latitude Indian station Hyderabad (17.41∘N, 78.55∘E). The variabilityis studied during the year 2014, by using the space borne Global Positioning System (GPS)observations. From GPS observations an important parameter; Total Electron Content (TEC)is obtained, which represents the integral electron density of the ionosphere and is widely usedin studies concerning ionospheric variability. We have studied how the ionospheric conditionsat Hyderabad change from hour to hour, day to day, month to month and season to season. Wefound that ionosphere over Hyderabad exhibits significant, interesting and regular variability.Although, the trends followed by the ionospheric changes are similar, but the magnitude ofpeak values differ on different time scales. Finally we have compared the variability of observedor actual values of TEC with the corresponding values predicted by International ReferenceIonosphere (IRI) model-2016 and found good agreement between hourly values, while IRImodel overestimates or underestimates the daily values.

The successful operation of communicational and navigational applications requires knowledgeof state and behaviour of ionosphere as well as spatial and temporal changes taking place init. With this view, we have studied the variability and changes in the low latitude ionosphereby considering a low latitude Indian station Hyderabad (17.41∘N, 78.55∘E). The variabilityis studied during the year 2014, by using the space borne Global Positioning System (GPS)observations. From GPS observations an important parameter; Total Electron Content (TEC)is obtained, which represents the integral electron density of the ionosphere and is widely usedin studies concerning ionospheric variability. We have studied how the ionospheric conditionsat Hyderabad change from hour to hour, day to day, month to month and season to season. Wefound that ionosphere over Hyderabad exhibits significant, interesting and regular variability.Although, the trends followed by the ionospheric changes are similar, but the magnitude ofpeak values differ on different time scales. Finally we have compared the variability of observedor actual values of TEC with the corresponding values predicted by International ReferenceIonosphere (IRI) model-2016 and found good agreement between hourly values, while IRImodel overestimates or underestimates the daily values.

 Ionospheric variability Total Electron Content International Reference Ionosphere-2016 model Ionospheric variability Total Electron Content International Reference Ionosphere-2016 model The authors are thankful to online data servers like SOPAC and CCMC-NASA for the data used in the study. We are also highly thankful to the anonymous reviewer for his valuable comments and suggestions

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