Real-time volcano monitoring using GNSS single-frequency receivers

• Published in: Journal of geophysical research. Solid earth 2015-12, Vol.120 (12), p.8551-8569
• Main Authors: Lee, Seung-Woo, Yun, Sung-Hyo, Kim, Do Hyeong, Lee, Dukkee, Lee, Young J., Schutz, Bob E.
• Format: Article
• Language: English
• Subjects: Case studies; Computer simulation; Data; Data processing; Deformation; Eruptions; Geophysics; Global navigation satellite system; GNSS; Inversions; Ionosphere; Ionospheric electron content; Monitoring; Navigation; Navigation satellites; Navigation systems; Owner operator; Real time; Receivers; Satellites; Solutions; Strategy; Volcano monitoring; Volcanoes; Water pollution
• ISSN: 2169-9313; 2169-9356
• DOI: 10.1002/2014JB011648

We present a real‐time volcano monitoring strategy that uses the Global Navigation Satellite System (GNSS), and we examine the performance of the strategy by processing simulated and real data and comparing the results with published solutions. The cost of implementing the strategy is reduced greatly by using single‐frequency GNSS receivers except for one dual‐frequency receiver that serves as a base receiver. Positions of the single‐frequency receivers are computed relative to the base receiver on an epoch‐by‐epoch basis using the high‐rate double‐difference (DD) GNSS technique, while the position of the base station is fixed to the values obtained with a deferred‐time precise point positioning technique and updated on a regular basis. Since the performance of the single‐frequency high‐rate DD technique depends on the conditions of the ionosphere over the monitoring area, the ionospheric total electron content is monitored using the dual‐frequency data from the base receiver. The surface deformation obtained with the high‐rate DD technique is eventually processed by a real‐time inversion filter based on the Mogi point source model. The performance of the real‐time volcano monitoring strategy is assessed through a set of tests and case studies, in which the data recorded during the 2007 eruption of Kilauea and the 2005 eruption of Augustine are processed in a simulated real‐time mode. The case studies show that the displacement time series obtained with the strategy seem to agree with those obtained with deferred‐time, dual‐frequency approaches at the level of 10–15 mm. Differences in the estimated volume change of the Mogi source between the real‐time inversion filter and previously reported works were in the range of 11 to 13% of the maximum volume changes of the cases examined. Key Points We present a real‐time volcano monitoring strategy using L1 GNSS receivers Performance of the strategy has been examined using tests and case studies The strategy can be an inexpensive alternative to dual‐frequency‐based strategies