First observations of super plasma bubbles in Europe

Ionospheric plasma bubbles of equatorial origin have never been registered at midlatitudes in Europe. During the 22–23 June 2015 geomagnetic storm the prompt penetration electric fields caused the occurrence of plasma bite-outs in the postsunset sector over low latitudes of Western Africa and large-scale plasma bubbles extended toward Europe. For the first time, using multisite GPS and Global Navigation Satellite System observations (~1500 stations), the super plasma bubble signatures were registered in Europe. They were observed more than 8 h (20–04 UT) and covered a broad area within 30°–40°N and 20°W–10°E. These unique results were confirmed by measurements on board Swarm and DMSP satellites and ground-based absolute total electron content observations. Occurrence of the super plasma bubbles in Europe affected Global Navigation Satellite Systems measurements over a number of stations in Spain, Portugal, southern France, and Italy and led to performance degradation of the European Geostationary Navigation Overlay Service.