NHESSD Natural Hazards and Earth System Sciences Discussions NHESSD Nat. Hazards Earth Syst. Sci. Discuss. 2195-9269 Göttingen, Germany 10.5194/nhess-2016-11 First GPS TEC maps of ionospheric disturbances induced by reflected tsunami waves: The Tohoku case study Tang L. 1 2 Zhao Y. 1 An J. 3 Key Laboratory of Earthquake Geodesy, Institute of Seismology, China Earthquake Administration, Wuhan 430071, China School of Geodesy and Geomatics, Wuhan University, Wuhan 430079, China Chinese Antarctic Center of Surveying and Mapping, Wuhan University, Wuhan 430079, China 26 01 2016 2016 1 14 Copyright: © 2016 L. Tang et al. 2016 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://nhess.copernicus.org/preprints/nhess-2016-11/ The full text article is available as a PDF file from https://nhess.copernicus.org/preprints/nhess-2016-11/nhess-2016-11.pdf

The straight tsunami waves from epicenter can be reflected when they reach to coasts or underwater obstacles. In this study, we present the first ionospheric maps of reflected tsunami signature caused by the great 11 March 2011 Tohoku earthquake using the dense GPS network GEONET in Japan. We observed tsunami-like travelling ionospheric disturbances (TIDs) with similar propagation characteristics in terms of waveform, horizontal velocity, direction, period and arrival time compared to the reflected tsunami at the sea-level, indicating the TIDs are induced by the reflected tsunami. The results confirm the atmospheric internal gravity waves (IGWs) produced by reflected tsunami can also propagate upward to the atmosphere and interact with the plasma at the ionospheric height.