Analysis of Ionospheric Responses During the Strong Geomagnetic Storm of 2024

Abstract

A major geomagnetic storm occurred on May 10–11, 2024, coinciding with Mother’s Day, and was classified as the most intense geomagnetic event since the 2003 "Halloween Storms". This storm induced significant disturbances in the magnetosphere–ionosphere system, driven by enhanced solar wind and interplanetary magnetic field (IMF) conditions. Observations from both ground-based instruments and low-Earth orbit satellites revealed a marked depletion in plasma density within the ionosphere, occurring within just a few hours after the onset of the storm. This depletion was particularly evident in the dawn and dusk sectors, where plasma flows were significantly suppressed. Ground-based measurements at magnetic latitudes above 50° also recorded substantial decreases in electron density. These geomagnetic variations were recorded by instruments installed at geomagnetic observatories. The initial depletion emerged near the polar cap during the early morning hours and subsequently expanded equatorward into the auroral and mid-latitude regions. The intense magnetospheric convection, driven by the storm-enhanced solar wind, is believed to have contributed to the erosion of the dayside plasmasphere, resulting in widespread plasma outflow and redistribution. The depleted ionospheric plasma density persisted for approximately three days post-storm before returning to pre-disturbance levels. Such ionospheric irregularities can critically affect space-based technologies, including satellite communications, GNSS-based navigation (e.g., GPS), and radio wave propagation. The instability of the ionosphere under geomagnetic storm conditions highlights the vulnerability of technological systems to extreme space weather events.