Abstract While low and high‐latitude ionospheric scintillation have been extensively reported, significantly less information is available about the properties of and conditions leading to mid‐latitude scintillations. Here, we report and discuss scintillation observations made in the Southern United States (UT Dallas, 32.99°N, 96.76°W, 43.2°N dip latitude) on June 1st, 2013. The measurements were made by a specialized dual‐frequency GPS‐based scintillation monitor which allowed us to determine main properties of this mid‐latitude scintillation event. Additionally, simultaneous airglow observations and ionospheric total electron content (TEC) maps provided insight on the conditions leading to observed scintillations. Moderate amplitude scintillations (S4>∼0.4) occurred in both L1 and L2C signals, and severe (S4 > ∼0.8) events occurred in L2C signals at low (<30°) elevation angles. Phase scintillation accompanied amplitude fadings, with maximum σϕvalues exceeding 0.5 radians in L2C. We also show that the observed phase scintillation magnitudes increased with amplitude scintillation severity. Decorrelation times were mostly between 0.25 and 1.25 s, with mean value around 0.65 s for both L1 and L2C. Frequency scaling of S4matched fairly well the predictions of weak scattering theory but held for observations of moderate and strong amplitude scintillation as well. Scintillation occurred during the main phase of a modest magnetic storm that, nevertheless, prompted an extreme equatorward movement of the mid‐latitude trough and large background TEC enhancements over the US. Scintillations, however, occurred within TEC and airglow depletions observed over Texas. Finally, scintillation properties including severity and rapidity, and associated TEC signatures are comparable to those associated with equatorial spread F.
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On the Extraordinary L‐Band Scintillation Event Observed in the American Sector During the 23–24 March 2023 Geomagnetic Storm
Abstract We report an extraordinary L‐band scintillation event detected in the American sector on the night of 23–24 March 2023. The event was detected using observations distributed from the magnetic equator to mid latitudes. The observations were made by ionospheric scintillation and total electron content (TEC) monitors 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 intense pre‐ and post‐midnight scintillations at JRO, a magnetic equatorial site where L‐band scintillation is typically weak and limited to pre‐midnight hours. The observations also show long‐lasting extremely intense L‐band scintillations detected by the CRT monitor. Additionally, the rare occurrence of intense mid‐latitude scintillation was detected by the UTD monitor around local midnight. Understanding of the ionospheric conditions leading to scintillation was assisted by TEC and rate of change of TEC index (ROTI) maps. The maps showed that the observed scintillation event was caused by equatorial plasma bubble (EPB)‐like ionospheric depletions reaching mid latitudes. TEC maps also showed the occurrence of an enhanced equatorial ionization anomaly throughout the night indicating the action of disturbance electric fields and creating conditions that favor the occurrence of severe scintillation. Additionally, the ROTI maps confirm the occurrence of pre‐ and post‐midnight EPBs that can explain the long duration of low latitude scintillation. The observations describe the spatio‐temporal variation and quantify the severity of the scintillation impact of EPB‐like disturbances reaching mid latitudes.
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- PAR ID:
- 10614818
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Space Weather
- Volume:
- 23
- Issue:
- 6
- ISSN:
- 1542-7390
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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