GPS TEC and Phase Variations during Substorms and Auroral Breakups
Abstract
The ionospheric structure caused by precipitation of high energy particles can adversely affect the GPS by causing an increase in the total electron content (TEC) and rapid variations of the phase that can result in loss of lock. The phase variations, sometimes called scintillation, are intense just after substorm onsets and auroral breakups. Temporal and spatial changes of TEC and phase variations are investigated in the context of equivalent ionospheric currents derived from ground magnetometer network using the spherical elementary current system method. The relation of the GPS phase variations to auroral emission is also examined. The phase variation is computed for sampling rate of 50 Hz by specialized GPS scintillation receivers from the Canadian High Arctic Ionospheric Network (CHAIN). A proxy index of phase variation is obtained from dual frequency measurements of geodetic-quality GPS receivers sampling at 1 Hz, which include globally distributed receivers of RT-IGS network that are monitored by the Canadian Geodetic Survey in near-real-time. In general, large GPS phase variations map to regions of strong westward electrojet and to the poleward edge of the eastward electrojet. Following substorm onsets and auroral breakups, large phase variations associated with TEC enhancements map mainly to the upward Region 2 current or the equatorward edge of the downward Region 1 current at or near the Harang discontinuity region.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMSA43C3229P
- Keywords:
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- 2427 Ionosphere/atmosphere interactions;
- IONOSPHERE;
- 2435 Ionospheric disturbances;
- IONOSPHERE;
- 2736 Magnetosphere/ionosphere interactions;
- MAGNETOSPHERIC PHYSICS;
- 2794 Instruments and techniques;
- MAGNETOSPHERIC PHYSICS