Ionospheric response to geomagnetic storm

Coronal mass ejections (CMEs) is undoubtedly the most spectacular transient events that cause an intense to extreme magnetic storms due to the occurrence of magnetic reconnection between the interplanetary magnetic field (IMF) and the geomagnetic field.  These storms occur due to the input of solar wind energy, which is sudden, into the magnetosphere-ionosphere-thermosphere system. Generally, a geomagnetic storm occurs following a Coronal Mass Ejection (CME) when the polarization of Interplanetary Magnetic Field (IMF) Bz changes from northward to southward, remain southward for several hours and reconnects with the Earth's magnetic field. The sources of geomagnetic storms may be divided into two categories based on their solar wind drivers, namely, CME and CIR. During geomagnetic storms, electric fields of solar wind origin penetrate the magnetosphere and equatorial ionosphere. Based on these fact, a report of ionospheric response to geomagnetic storm are investigated by analyzing ionograms to provide essential information needed to understand the factors that influence ionospheric dynamics. Its importance is attributed to its effects on the radio waves propagation between satellites and ground-based receivers, which in its turn affect global navigation and positioning systems. In this workshop, I will present the investigation of ionospheric response to CMEs, and disturbance drifts using a model to verify the combine effect of Prompt penetration of electric field (PPEF) and Disturbance dynamo electric field (DDEF) that produce significant changes in the equatorial ionosphere. Finally, Solar wind parameters, geomagnetic indices, O / N2 ratios retrieved by GUVI instrument onboard the TIMED satellite and TEC observations will be analyzed and discussed to verify the changes in the neutral atmospheric composition during the disturbances.