Detecting ionospheric TEC perturbations caused by natural hazards using a global network of GPS receivers: The Tohoku case study

Abstract

Recent advances in GPS data processing have demonstrated that ground-based GPS receivers are capable of detecting ionospheric TEC perturbations caused by surface-generated Rayleigh, acoustic and gravity waves. There have been a number of publications discussing TEC perturbations immediately following the M 9.0 Tohoku earthquake in Japan on March 11, 2011. Most investigators have focused on the ionospheric responses up to a few hours following the earthquake and tsunami. In our research, in addition to March 11, 2011 we investigate global ionospheric TEC perturbations a day before and after the event. We also compare indices of geomagnetic activity on all three days with perturbations in TEC, revealing strong geomagnetic storm conditions that are also apparent in processed GEONET TEC observations. In addition to the traveling ionospheric disturbances (TIDs) produced by the earthquake and tsunami, we also detect "regular" TIDs across Japan about 5 hours following the Tohoku event, concluding these are likely due to geomagnetic activity. The variety of observed TEC perturbations are consistent with tsunami-generated gravity waves, auroral activity, regular TIDs and equatorial fluctuations induced by increased geomagnetic activity. We demonstrate our capabilities to monitor TEC fluctuations using JPL's real-time Global Assimilative Ionospheric Model (GAIM) system. We show that a real-time global TEC monitoring network is able to detect the acoustic and gravity waves generated by the earthquake and tsunami. With additional real-time stations deployed, this new capability has the potential to provide real-time monitoring of TEC perturbations that could potentially serve as a plug-in to enhance existing early warning systems.

Dynamics of vertical ionospheric inhomogeneities over Irkutsk during 06:00–06:20UT 11/03/2011 caused by Tohoku earthquake

“…Ionospheric effects of the Tohoku earthquake are currently the subject of many papers. Above all, it is papers analyzing data from dense networks of GPS-receivers, located on the Asian territory (Akhoondzadeh, 2012;Kakinami et al, 2011;Astafyeva et al, 2013;Hao et al, 2012;Komjathy et al, 2012;Liu, 2012;Occhipinti et al, 2011;Ogawa et al, 2012;Ouzounov et al, 2011;Saito et al, 2011;Tsugawa et al, 2011) and data from the SuperDARN radar, located on the Hokkaido island (Nishitani et al, 2011;Ogawa et al, 2012). These instruments have the best temporal resolution -from several seconds to 2 minutes, enabling to monitor the highly dynamic processes.…”

Ionospheric Anomaly due to the volcanic eruption in Colima, Mexico, 06 January 2013: Two-Dimensional Principal Component Analysis

“…According to the statements in the section one, studies of TEC disturbance suggest some possible explanations for eruption-related TEC anomalies. The effect of shock acoustic wave is a possible cause from the work of Komjathy et al [2012]. To confirm this, Afraimovich et al [2001] researched how shock acoustic waves produced by earthquakes affect the ionosphere.…”

“…However, our study focuses on the ionospheric response due to volcanic eruptions [Argelia et al, 2004;Dautermann et al, 2009aDautermann et al, , 2009bZlotnicki et al, 2010;Komjathy et al, 2012]. Similar ionospheric disturbances caused by volcanic eruptions have been documented in North and South America.…”

“…However, determining a method of predicting volcanic eruptions remains a largely unsolved problem. Komjathy et al [2012] has mentioned that volcanic eruptions generate acoustic and gravitational waves that can cause TEC perturbations. At ionospheric heights, the coupling between neutral particles and free electrons induces electron density fluctuations.…”

Detection of ionospheric disturbances driven by the 2014 Chile tsunami using GPS total electron content in New Zealand

“…However, both Doppler sounding networks and altimetry satellites have limited coverage, which make it difficult to study the propagation characteristics of TIDs in detail. With the progress of high-density global positioning system (GPS) stations network, the GPS TEC data have been widely used in ionospheric monitoring and tsunami detection [Artru et al, 2005;Liu et al, 2006b;DasGupta et al, 2006;Rolland et al, 2010;Liu et al, 2011;Makela et al, 2011;Tsugawa et al, 2011;Galvan et al, 2012;Komjathy et al, 2012;Occhipinti et al, 2013;Tang et al, 2015].…”