سرى اسماعيل جبوري

Email: surajabory@yahoo.com

Abstract:

In this research the variation of Total Electron Content (TEC) obtained by using Global Position Satellite system (GPS) during the different kinds of geomagnetic storms. TEC data selected for years 2000-2010 (descending solar cycle 23 to ascending cycle 24), as available from Koyota Japan wdc. To find out the type of geomagnetic storms the Disturbance storm time (Dst) index was selected for the years (2000-2010) from the same site. Data from UK WDC are taken for the solar indices sunspots number (SSN), radio flux (F10.7) and ionosphere index parameter (IG12). The predicted TEC are calculated from IRI model, the TEC behavior was performed on data representing nearly 80 storm events from (2000-2010)  at location (33° N, 133° E) over Japan sector (mid-latitudes region). At the present work  all effects on TEC values were studied such as (magnetic storms, diurnal, and season). It found that geomagnetic storms effect on TEC  than in case there is no storm, and the TEC values proportionally with the strength of geomagnetic storms type. Comparing between the diurnal observed (GPS) TEC and predicted from (IRI-2007 model), it is found that, in general the IRI model shows a good correlation at no storm but there is more differ in major storms. The TEC reveals a high values at day time but minimum at the night due to solar effect, there is two or more than two peaks appeared (at day time) when two type of storms appeared in the same event due to drag of ionosphere from high to low latitudes. The seasonal effect of the TEC values especially in Spring it reveals a higher values than other seasons, in case