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Abstract This study investigates midlatitude ionospheric variations during the super geomagnetic storm on 10–11 May 2024, utilizing multi‐instrument data from ground‐based sources (Global Navigation Satellite Systems receivers and a Fabry–Perot Interferometer) and space‐based measurements (Swarm and DMSP). We observed several distinct density gradient structures in the midlatitude ionosphere, with the main findings summarized as follows: (a) Significant zonal plasma density enhancements developed continuously in local dusk across the American‐Pacific‐Asian longitude sectors around geomagnetic latitude. These midlatitude peaks exhibited a wide longitudinal extension exceeding 150 and a prolonged duration of 12–15 hr during the late main phase and early recovery phase of the storm. (b) Strong storm‐enhanced density (SED) was observed in both hemispheres yet with different longitudinal and universal time preferences. In the Northern Hemisphere, significant SED occurred over the American longitude sector during 20:30–22:30 UT on May 10. In the Southern Hemisphere, pronounced SED was observed not only in the American longitudes during 20:30–22:30 UT on May 10 but also in the Australian longitude sector during 02:00–04:00 UT on May 11.
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This content will become publicly available on January 1, 2026
Multi-instrument observations of ionospheric super plasma bubbles in the European longitude sector during the 23–24 April 2023 severe geomagnetic storm
This study’s objective is to better specify the rare occurrence of super equatorial plasma bubbles in particular to the European longitude sector, detailing their spatio-temporal evolution, and better understanding pre-conditions for their development. Our comprehensive multi-instrument analysis combined ground-based and space observations from GNSS, ionosondes, and several satellite missions (COSMIC-2, GOLD, Swarm). We have investigated the ionospheric response to the 23–24 April 2023 severe geomagnetic storm and have shown the formation of super plasma bubbles expanding from equatorial latitudes to middle latitudes in the European/African sector during the main phase of the storm. Formation of these super bubbles was associated with storm-induced prompt penetration electric fields. We found that the area affected by the formation of numerous plasma bubbles covered more than 5000 km ranging from 30°W to 30°E in the Atlantic/African sector. The bubbles also had an impressive north-south extension, reaching as far poleward as ~30°–35° latitude in both hemispheres. After 20 UT on 23 April 2023, the zone with equatorial ionospheric irregularities reached Northern Africa, the Iberian Peninsula (Spain, Portugal) and the Mediterranean Sea in southern Europe, including areas of the Canary Islands (Spain) and the Azores and Madeira Islands (Portugal) in the Atlantic Ocean. The ionospheric irregularities persisted for 5–6 h and began to fade after ~01 UT on 24 April 2023. COSMIC-2 scintillation measurements showed intense amplitude scintillations (S4 above 0.8) across this entire region, indicating presence of small-scale ionospheric irregularities inside the extended plasma bubbles. During this storm, EGNOS (European Geostationary Navigation Overlay Service) experienced degraded performance, with significant navigation errors recorded at its southernmost stations in Northern Africa, Spain, Portugal, and their territories, which were affected by super plasma bubbles. This paper presents conclusive observational evidence showing development of the super plasma bubbles significantly expanding into the southern Europe and northern Africa region under geomagnetically disturbed conditions in April 2023.
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- Award ID(s):
- 2054356
- PAR ID:
- 10615435
- Publisher / Repository:
- EDP Sciences
- Date Published:
- Journal Name:
- Journal of Space Weather and Space Climate
- Volume:
- 15
- ISSN:
- 2115-7251
- Page Range / eLocation ID:
- 5
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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