Experimental Evidence on the Dependence of the Standard GPS Phase Scintillation Index on the Ionospheric Plasma Drift Around Noon Sector of the Polar Ionosphere

• Published in: Journal of Geophysical Research: Space Physics
• Main Authors: Wang, Y., Zhang, Q.-H., Jayachandran, P. T., Moen, J., Xing, Z.-Y., Chadwick, R., Ma, Y.-Z., Ruohoniemi, J. M., Lester, M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union (AGU), Wiley 2018
• Subjects: Science & Technology; Physical Sciences; Astronomy & Astrophysics; SCALE IRREGULARITIES; CONVECTION; LATITUDES; SUPERDARN; REGIONS; Arctic; Canada; Norway; Lester; Moen; Canadian High Arctic Ionospheric Network
• Online Access: https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2017JA024805; http://hdl.handle.net/2381/42656; https://doi.org/10.1002/2017JA024805

The file associated with this record is under embargo until 6 months after publication, in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above. First experimental proof of a clear and strong dependence of the standard phase scintillation index (σφ) derived using Global Positioning System measurements on the ionospheric plasma flow around the noon sector of polar ionosphere is presented. σφ shows a strong linear dependence on the plasma drift speed measured by the Super Dual Auroral Radar Network radars, whereas the amplitude scintillation index (S4) does not. This observed dependence can be explained as a consequence of Fresnel frequency dependence of the relative drift and the used constant cutoff frequency (0.1 Hz) to detrend the data for obtaining standard σφ. The lack of dependence of S4 on the drift speed possibly eliminates the plasma instability mechanism(s) involved as a cause of the dependence. These observations further confirm that the standard phase scintillation index is much more sensitive to plasma flow; therefore, utmost care must be taken when identifying phase scintillation (diffractive phase variations) from refractive (deterministic) phase variations, especially in the polar region where the ionospheric plasma drift is much larger than in equatorial and midlatitude regions. This work in China is supported by the National Natural Science Foundation (grants 41574138, 41274149, and 41604139), the young top‐notch talent program of the “National High‐level personnel of special support program (Ten Thousand Talent Program),” and the Shandong Provincial Natural Science Foundation (grant JQ201412) and the Chinese meridian project. All the GPS data used in this work were provided by the Canadian High Arctic Ionospheric Network (CHAIN); the official website is http://chain.physics.unb.ca/chain/. Infrastructure funding for CHAIN was provided by the Canada Foundation for Innovation (CFI) and the New Brunswick Innovation Foundation (NBIF). CHAIN and its operation are conducted in collaboration with the Canadian Space Agency (CSA). Science funding is provided by the Natural Sciences and Engineering Research Council of Canada (NSERC). J. Moen is supported by the Research Council of Norway grant 230996. M. Lester acknowledges support from STFC grant ST/K001000/1 and NERC grant NE/K011766/1. We greatly appreciate the Physics department of University of New Brunswick for establishing and running CHAIN and sharing scintillation data through database http://chain.physics.unb.ca/chain/pages/gps/). We also sincerely acknowledge Virginia Tech. for providing SuperDARN radar data through website (http://vt.superdarn.org/tiki‐index.php). SuperDARN is a collection of radars funded by national scientific funding agencies of Australia, Canada, China, France, Japan, South Africa, UK, and United States. The Kapuskasing HF radar is operating by Virginia Tech., and the Saskatoon HF radar is maintaining by University of Saskatchewan. The authors also wish to thank the International Space Science Institute in Beijing (ISSI‐BJ) for supporting and hosting the meeting of the International Team on “Multiple‐instrument observations and simulations of the dynamical processes associated with polar cap patches/aurora and their associated scintillations,” during which the discussions leading/contributing to this publication were held. Peer-reviewed Publisher Version