During the active space weather periods, the transfer of solar wind energy and momentum to Earth's magnetosphere-ionosphere system leads to a variety of neutral and electrodynamical processes causing severe disturbances in the ionosphere. The equatorial Ionosphere is one of the most vulnerable regions that exhibit dramatic changes in electron density distribution during this period. During geomagnetic storms, the particle and joule heating at high latitudes drives a global scale thermospheric wind dynamo, generally known as Ionospheric Disturbance Dynamo (IDD) (Blanc & Richmond, 1980). Further, the high latitude region 1 and region 2 field-aligned currents also induce strong convection and overshielding electric fields which penetrates promptly to the equatorial ionosphere, known as Prompt Penetration Electric Field (PPEF) (Kikuchi et al., 1996(Kikuchi et al., , 2000Nishida, 1968). The electric field perturbation associated with the above processes (IDD, strong convection, and overshielding electric fields) as well as neutral disturbances can significantly alter the electron density distribution of equatorial and low latitude ionosphere (

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