Articles | Volume 31, issue 5
Ann. Geophys., 31, 805–816, 2013
Ann. Geophys., 31, 805–816, 2013

Regular paper 06 May 2013

Regular paper | 06 May 2013

GPS phase scintillation and proxy index at high latitudes during a moderate geomagnetic storm

P. Prikryl1, R. Ghoddousi-Fard2, B. S. R. Kunduri3, E. G. Thomas3, A. J. Coster4, P. T. Jayachandran5, E. Spanswick6, and D. W. Danskin7 P. Prikryl et al.
  • 1Communications Research Centre, Ottawa, ON, Canada
  • 2Geodetic Survey Division, Natural Resources Canada, Ottawa, ON, Canada
  • 3Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, VA, USA
  • 4Haystack Observatory, Massachusetts Institute of Technology, Westford, MA, USA
  • 5Physics Dept, University of New Brunswick, Fredericton, NB, Canada
  • 6Department of Physics and Astronomy, University of Calgary, AB, Canada
  • 7Geomagnetic Laboratory, Natural Resources Canada, Ottawa, ON, Canada

Abstract. The amplitude and phase scintillation indices are customarily obtained by specialised GPS Ionospheric Scintillation and TEC Monitors (GISTMs) from L1 signal recorded at the rate of 50 Hz. The scintillation indices S4 and σΦ are stored in real time from an array of high-rate scintillation receivers of the Canadian High Arctic Ionospheric Network (CHAIN). Ionospheric phase scintillation was observed at high latitudes during a moderate geomagnetic storm (Dst = −61 nT) that was caused by a moderate solar wind plasma stream compounded with the impact of two coronal mass ejections. The most intense phase scintillation (σΦ ~ 1 rad) occurred in the cusp and the polar cap where it was co-located with a strong ionospheric convection, an extended tongue of ionisation and dense polar cap patches that were observed with ionosondes and HF radars. At sub-auroral latitudes, a sub-auroral polarisation stream that was observed by mid-latitude radars was associated with weak scintillation (defined arbitrarily as σΦ < 0.5 rad). In the auroral zone, moderate scintillation coincided with auroral breakups observed by an all-sky imager, a riometer and a magnetometer in Yellowknife. To overcome the limited geographic coverage by GISTMs other GNSS data sampled at 1 Hz can be used to obtain scintillation proxy indices. In this study, a phase scintillation proxy index (delta phase rate, DPR) is obtained from 1-Hz data from CHAIN and other GPS receivers. The 50-Hz and 1-Hz phase scintillation indices are correlated. The percentage occurrences of σΦ > 0.1 rad and DPR > 2 mm s−1, both mapped as a function of magnetic latitude and magnetic local time, are very similar.