Real-Time Detection of Tsunami Ionospheric Disturbances with a Stand-Alone GNSS Receiver: A Preliminary Feasibility Demonstration

Abstract

It is well known that tsunamis can produce gravity waves that propagate up to the ionosphere generating disturbed electron densities in the E and F regions. These ionospheric disturbances can be studied in detail using ionospheric total electron content (TEC) measurements collected by continuously operating ground-based receivers from the Global Navigation Satellite Systems (GNSS). Here, we present results using a new approach, named VARION (Variometric Approach for Real-Time Ionosphere Observation), and estimate slant TEC (sTEC) variations in a real-time scenario. Using the VARION algorithm we compute TEC variations at 56 GPS receivers in Hawaii as induced by the 2012 Haida Gwaii tsunami event. We observe TEC perturbations with amplitudes of up to 0.25 TEC units and traveling ionospheric perturbations (TIDs) moving away from the earthquake epicenter at an approximate speed of 316 m/s. We perform a wavelet analysis to analyze localized variations of power in the TEC time series and we find perturbation periods consistent with a tsunami typical deep ocean period. Finally, we present comparisons with the real-time tsunami MOST (Method of Splitting Tsunami) model produced by the NOAA Center for Tsunami Research and we observe variations in TEC that correlate in time and space with the tsunami waves.

Ionospheric Detection of Natural Hazards

“…CTID match the period, velocity, and propagation direction of the tsunamis causing them. Consequently, tracking CTID provides an opportunity to follow the propagation of tsunamis and can potentially be used for near‐real‐time tsunami warning systems (e.g., Najita et al, ; Savastano et al, ).…”

“…CTID match the period, velocity, and propagation direction of the tsunamis causing them. Consequently, tracking CTID provides an opportunity to follow the propagation of tsunamis and can potentially be used for near-real-time tsunami warning systems (e.g., Najita et al, 1974;Savastano et al, 2017). Hines (1972) and Peltier and Hines (1976) were the first who theoretically predicted that sea surface variations typical of tsunamis can seed internal gravity waves with amplitudes strong enough to generate ionospheric signatures.…”

“…However, despite numerous efforts, the classic methods still fail to correctly estimate the magnitude of large earthquakes (Mw > 8) in real time, and therefore, they also fail to correctly estimate the tsunami potential. In response to this need, it has recently been suggested that the ionosphere-based technique could, in future, present a novel approach for NH-detection in near-real time (e.g., Savastano et al, 2017). Huang et al (2019) have recently provided an extended review on ionospheric detection of explosive events.…”

Coseismic displacements on Ischia island, real-time GPS positioning constraints on earthquake source location

“…GPS data have proven the potential of early tsunami warning [Blewitt et al, 2007;Sobolev et al, 2007;Singh et al, 2012;Hoechner et al, 2013;Savastano et al, 2017]. In literature, so far, the focus is mainly on the advantages of the GPS data in recovering large earthquake parameters, but recently there is a growing interest in developing automated algorithms for real-time determinations of seismological parameters and deformation analysis for smaller seismic events [Melgar et al, 2015;Crowell et al, 2016].…”

Statistical Observation of Thunderstorm-Induced Ionospheric Gravity Waves above Low-Latitude Areas in the Northern Hemisphere

“…Here, we call the GW signals of ionospheric disturbances ionospheric GWs. Studies have shown that various origins, including solid earth events, such as earthquakes and tsunamis [6][7][8][9], and tropospheric weather events, such as typhoons, penetrative convections, and jet streams [10][11][12], can trigger GWs and propagate upwards to ionospheric height.…”