Understanding of plasma irregularities induced by Space Weather

Abstract:

Gaining new knowledge on morphology and spatio-temporal dynamics of the ionospheric plasma irregularities, their dependences on geophysical factors, is an important and challenging task. The plasma irregularities that occurred at high, middle and low latitudes have different physical mechanisms of their origin and development. The objectives of this study are to analyze features of the ionospheric irregularities’ development at midlatitudes during severe geomagnetic storms and to estimate physical drivers leading to these structures’ generation. During geomagnetic storms, plasma irregularities occurring at midlatitudes have typically an auroral origin and resulted from energetic particles precipitations in subauroral region. However, an unpredictable extreme event is an occurrence of plasma irregularities of equatorial origin at midlatitudes. The storm-induced prompt penetration electric fields can cause an occurrence of the severe plasma bite-outs in the post-sunset sector over equatorial latitudes and development of large-scale plasma bubbles extended toward midlatitudes. Development of such super plasma bubbles can cause GNSS performance degradation. We analyze an occurrence and evolution of the ionospheric plasma irregularities during the 22–23 June 2015 geomagnetic storm. We examine global features of the large-scale plasma depletion by using a combination of ground-based and space-borne measurements - ground-based GNSS networks, COSMIC GPS RO, Swarm GPS and in-situ observations, and in situ data from onboard the C/NOFS satellite. It was investigated relationships between space weather drivers and processes of plasma irregularities development in order to reviled global drivers originated these processes. We also demonstrate to which extent an integration of independent but compatible modern ground-based and space-borne observations can support studies on the origin and dynamics of ionospheric plasma irregularities in a view of the COSMIC-2 mission.