Application of GNSS networks to detect and analyze atmospheric-induced ionospheric disturbances coincident with earthquakes and tsunamis

Traveling ionospheric disturbances (TIDs) induced by acoustic-gravity waves(AGWs) in the neutral atmosphere are subsequently observable in trans-ionospheric Global Navigation Satellite System (GNSS) measurements. Disruptive events on the Earth´s surface, such as earthquakes, tsunamis and large explosions are one source of these disturbances. In this study, we apply a wavelet method to enhance the cross-correlation technique for detecting the presence of TIDs in dual frequency IEC time series collected from GNSS networks. Data were collected after the March 11, 2011 earthquake in Japan and the February 27, 2010 earthquake in Chile. Both earthquakes produced large tsunamis. Through use of the wavelet coherence analysis, we are able to find major a wave train, present in the data collected from these networks, with two dominant frequency bands.