Signatures of Equatorial Plasma Bubbles and Ionospheric Scintillations from Magnetometer and GNSS Observations in the Indian Longitudes during the Space Weather Events of Early September 2017

Ram Kumar Vankadara (1) , Sampad Kumar Panda (1) , Christine Amory-Mazaudier (2, 3) , Rolland Fleury (4, 5) , Venkata Ratnam Devanaboyina (1) , Tarun Kumar Pant (6) , Punyawi Jamjareegulgarn (7) , Mohd Anul Haq (8) , Daniel Okoh (9, 10) , Gopi Krishna Seemala (11)

1 koneru laxmiah education foundation
2 LPP - Laboratoire de Physique des Plasmas
3 ICTP - Abdus Salam International Centre for Theoretical Physics [Trieste]
4 Lab-STICC - Laboratoire des sciences et techniques de l'information, de la communication et de la connaissance
5 IMT Atlantique - MO - Département Micro-Ondes
6 Space Physics Laboratory
7 KMITL - King Mongkut’s Institute of Technology Ladkrabang
8 Majmaah University
9 CAR-NSRDA - Center for Atmospheric Research [Nigéria]
10 African University of Science and Technology
11 IIG - Indian Institute of Geomagnetism [Navi Mumbai, India]

Scintillation due to ionospheric plasma irregularities remains a challenging task for the space science community as it can severely threaten the dynamic systems relying on space-based navigation services. In the present paper, we probe the ionospheric current and plasma irregularity characteristics from a latitudinal arrangement of magnetometers and Global Navigation Satellite System (GNSS) stations from the equator to the far low latitude location over the Indian longitudes, during the severe space weather events of 6–10 September 2017 that are associated with the strongest and consecutive solar flares in the 24th solar cycle. The night-time influence of partial ring current signatures in ASYH and the daytime influence of the disturbances in the ionospheric E region electric currents (Diono) are highlighted during the event. The total electron content (TEC) from the latitudinal GNSS observables indicate a perturbed equatorial ionization anomaly (EIA) condition on 7 September, due to a sequence of M-class solar flares and associated prompt penetration electric fields (PPEFs), whereas the suppressed EIA on 8 September with an inverted equatorial electrojet (EEJ) suggests the driving disturbance dynamo electric current (Ddyn) corresponding to disturbance dynamo electric fields (DDEFs) penetration in the E region and additional contributions from the plausible storm-time compositional changes (O/N2) in the F-region. The concurrent analysis of the Diono and EEJ strengths help in identifying the pre-reversal effect (PRE) condition to seed the development of equatorial plasma bubbles (EPBs) during the local evening sector on the storm day. The severity of ionospheric irregularities at different latitudes is revealed from the occurrence rate of the rate of change of TEC index (ROTI) variations. Further, the investigations of the hourly maximum absolute error (MAE) and root mean square error (RMSE) of ROTI from the reference quiet days’ levels and the timestamps of ROTI peak magnitudes substantiate the severity, latitudinal time lag in the peak of irregularity, and poleward expansion of EPBs and associated scintillations. The key findings from this study strengthen the understanding of evolution and the drifting characteristics of plasma irregularities over the Indian low latitudes.

Mots clés: space weather; storm-time electric currents; magnetometer; global navigation satellite system; rate of change of TEC index; ionospheric irregularity; equatorial plasma bubbles; scintillations; poleward drift

Domaines: Sciences de l'environnement

Ram Kumar Vankadara, Sampad Kumar Panda, Christine Amory-Mazaudier, Rolland Fleury, Venkata Ratnam Devanaboyina, et al.. Signatures of Equatorial Plasma Bubbles and Ionospheric Scintillations from Magnetometer and GNSS Observations in the Indian Longitudes during the Space Weather Events of Early September 2017. Remote Sensing, 2022, 14 (3), pp.652. ⟨10.3390/rs14030652⟩. ⟨hal-03597270⟩