Topside Low‐Latitude Ionospheric Response to the 10–11 May 2024 Super Geomagnetic Storm as Observed by Swarm: The Strongest Storm‐Time Super‐Fountain During the Swarm Era?

Abstract

The current study explores how the topside equatorial and low-latitude ionosphere responded to the super geomagnetic storm on 10–11 May 2024, using in situ data from the Swarm constellation. During the storm's main phase, enhancements in the EIA (equatorial ionization anomaly) were observed, forming strong super-fountains. The EIAs were extended toward latitudes beyond ±30° of the magnetic equator, with the crests of the EIAs being shifted to ∼25° of the magnetic equator on both hemispheres during the main phase of the storm. Swarm-A observed the strongest storm-time super-fountain during its entire age (2013-present) with nearly 500% increase in the crest density compared to the quiet-time conditions. During the recovery phase, the EIA was suppressed entirely, and density crests were observed over the magnetic equator, and troughs were observed at locations around ∼10° – 15°of magnetic dip latitude.