An extreme scintillation event observed in the American sector during the geomagnetic storm of March 23-24, 2023

We report an extraordinary L-band scintillation event detected in the American sector on the night of March 23-24, 2023. The event was detected by GNSS-based ionospheric scintillation and total electron content (TEC) monitors (ScintPi) deployed at the Jicamarca Radio Observatory (JRO, ~-1° dip latitude), at the Costa Rica Institute of Technology (CRT, ~20° dip latitude), and at The University of Texas at Dallas (UTD, ~42° dip latitude).

The observations show strong L-Band scintillations in the pre- and post-midnight sector at JRO, a magnetic equatorial site where L-band scintillations are usually weak and confined to pre-midnight hours. The observations also show extremely intense amplitude L-band scintillations lasting for over 10 hours at CRT. Finally, the UTD monitor detected the rare occurrence of intense mid-latitude L-Band scintillation around local midnight.

TEC and rate of change of TEC index (ROTI) maps provided insight into the ionospheric conditions responsible for scintillation. These maps revealed that the observed scintillation event resulted from equatorial plasma bubble (EPB)-like ionospheric depletions extending to mid-latitudes.

The ScintPi observations quantify the scintillation impact of extreme EPB-like disturbances reaching mid-latitudes. We highlighted that the TEC maps also reveal a persistent enhancement of the equatorial ionization anomaly throughout the night, indicating the influence of disturbance electric fields and creating conditions conducive to severe L-band scintillation.

Acknowledgments: Work at UTD was supported by the National Science Foundation (Awards AGS- 2122639 and AGS- 2432609) and by NASA (80NSSC24K0563).