The Impact of 11 May 2024 Great Geomagnetic Storm on the Plasma Distribution Over the Indian Equatorial/Low Latitude Ionospheric Region

Abstract

This study investigates the effects of the great geomagnetic storm of May 10–11, 2024, on the plasma density distribution in the ionosphere over the Indian equatorial and low-latitude regions. We utilized Vertical Total Electron Content (VTEC) as a proxy to understand the plasma density distribution. In conjunction with the equatorward neutral wind from the auroral region, the strom generated strong convective electric fields, penetrating down to the dip-equator, played a cruicial role in causing VTEC reduction at night (main phase) and enhancement during the day (recovery phase) on 11 May. Simultaneously, a decrease in VTEC of over 60% was observed in Bhopal, an equatorial ionization anomaly crest region. Undulations in the VTEC at the dip-equator correlated well with interplanetary electric field (IEFy) and magnetic field ($\Delta$H) fluctuations. Analysis of the AE index suggests a strong equatorward wind surge due to intense auroral heating during the storm. Since the great storm occurred at night over India, meridional wind circulation played a prominent role. This study highlights the need for a more detailed analysis using multiple instruments and models to understand the response of the Indian equatorial and low-latitude regions during geomagnetic storms.