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Abstract Substorms produce rapid fluctuations in Global Navigation Satellite System (GNSS) signals, leading to degraded positioning performance at high latitudes. This study investigates the correlation of auroral structures on Global Positioning System (GPS) Precise Point Positioning (PPP) error during three substorm events with different strengths, showing that stronger substorms tend to produce larger position errors. Using a combination of GPS and auroral optical data from nearly 100 ground stations in Alaska, we identify spatial and temporal relations between phase fluctuations, total electron content enhancements, and PPP error. The most severe PPP error, reaching 50 m and losing position solution, occurred during the substorm expansion phase and was co‐located with discrete auroral arcs including the poleward boundary of the substorm bulge and auroral streamers. Moderate phase fluctuations and PPP error were also observed over diffuse aurora as a widespread feature of the auroral oval that has traditionally not been considered a significant contributor to scintillation. The vertical component of the position errors, which has practical significance for aviation applications, was larger than the horizontal position errors. These results indicate that high‐latitude GNSS degradation is related to substorm strength and active auroral forms, including both discrete and diffuse auroras. The results highlight the importance of considering various types of auroral forms in future mitigation strategies.
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Subauroral TEC Enhancement, GNSS Scintillation, and Positioning Error During STEVE
Abstract We report the first simultaneous observations of total electron content (TEC), radio signal scintillation, and precise point positioning (PPP) variation associated with Strong Thermal Emission Velocity Enhancement (STEVE) emissions during a 26 March 2008 storm‐time substorm. Despite that the mid‐latitude trough TEC decreases during the substorm overall, interestingly, we found an unexpected TEC enhancement (by ∼2 TECU) during STEVE. Enhancement of vertical TEC and phase scintillation was highly localized to STEVE within a thin latitudinal band of 1°. As STEVE shifted equatorward, TEC enhancement was found at and slightly poleward of the optical emission. PPP exhibited enhanced variation across a 3° latitudinal range around STEVE and indicated increased GNSS positioning error. We suggest that TEC enhancement during STEVE creates local TEC structures in the ionosphere that degrade Global Navigation Satellite Systems (GNSS) signals and PPP performance. The TEC enhancement may be created by particle precipitation, Pedersen drift across STEVE, neutral wind, or plasma instability.
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- PAR ID:
- 10612852
- Publisher / Repository:
- Journal of Geophysical Research
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Space Physics
- Volume:
- 129
- Issue:
- 12
- ISSN:
- 2169-9380
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1029/2024JA033345
