Multi‐Instrumental Observation of Storm‐Induced Ionospheric Plasma Bubbles at Equatorial and Middle Latitudes

Abstract

AbstractJune solstice is considered as a period with the lowest probability to observe typical equatorial plasma bubbles (EPBs) in the postsunset period. The severe geomagnetic storm on 22–23 June 2015 has drastically changed the situation. Penetrating electric fields associated with a long‐lasting southward IMF support favorable conditions for postsunset EPBs generation in the dusk equatorial ionosphere for several hours. As a result, the storm‐induced EPBs were progressively developed over a great longitudinal range following the sunset terminator. The affected area has a large longitudinal range of ~100° in the American sector and a rather localized zone of ~20° in longitude in the African sector. Plasma depletions of equatorial origin were registered at midlatitudes (30°–40° magnetic latitude) of both hemispheres in the African and American longitudinal sectors. We examine global features of the large‐scale plasma depletion by using a combination of ground‐based and space‐borne measurements—ground‐based Global Positioning System/Global Navigation Satellite System (GPS/GNSS) networks, Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) GPS Radio Occultation (RO), Swarm upward looking GPS data, and in situ plasma density observations provided by Swarm, Communications/Navigation Outage Forecasting System (C/NOFS), and Defense Meteorological Satellite Program (DMSP) missions. Joint analysis of the satellite observations revealed that these storm‐induced EPBs structures had extended over 500 km in altitude, at least from ~350 to ~850 km. These irregularities caused strong amplitude and phase scintillations of GPS/GNSS signals for ground‐based and space‐borne (COSMIC RO) measurements and seriously affected performance of navigation‐based services.