The Ionospheric Response During the Super Geomagnetic Storm on May 10–11, 2024

Abstract

The ionospheric response in the Americas and Asia region was studied during the super geomagnetic storm on 10–11 May, 2024, characterized by a minimum Dst of −412 nT. Global Navigation Satellite System receivers at $100°W$ and $100°E$ were utilized to study total electron content. Additionally, electron density profiles from Constellation Observing System for Meteorology Ionosphere and Climate occultation, foF2 from ionosondes, vertical ion drift from JULIA Medium Power radar, latitudinal distribution of electron density from Swarm B, and the [O/N2] ratios from TIMED/GUVI were also analyzed. The ionosphere in the Americas exhibited a positive storm, while Asia showed a negative storm. The presence of prompt penetration electric field and the equatorward wind surge were indicated by the increased upward ion drift and the enhancement of equatorial ionospheric anomalies (EIA). The observations of [O/N2] confirm the existence of equatorward expansion of neutral atmosphere, and the time delay of $\Delta TEC$ peak at mid-latitudes was related to the equatorward wind surge. For the first time, we investigated the dominant physical mechanism of ionospheric disturbance at different latitudes by analyzing the variation of $\Delta TEC$ peak time with latitude. The estimated speed of disturbance winds was approximately 660 m/s at $50°N$ and 150 m/s at $37°N$. The positive storm was likely caused by the disturbance dynamo electric field and wind convergence in both regions during the recovery phase.