Review:

# Role of Real-Time GNSS in Near-Field Tsunami Forecasting

## Yusaku Ohta^{*,†}, Takuya Inoue^{**}, Shunichi Koshimura^{**}, Satoshi Kawamoto^{***}, and Ryota Hino^{*}

^{*}Research Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science, Tohoku University

6-6 Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan

^{†}Corresponding author

^{**}International Research Institute of Disaster Science, Tohoku University, Sendai, Japan

^{***}Geospatial Information Authority of Japan, Tsukuba, Japan

This short paper reviews the role of real-time global navigation satellite system (GNSS) in near-field tsunami forecasting. Recent efforts highlight that coseismic fault model estimation based on real-time GNSS has contributed substantially to our understanding of large magnitude earthquakes and their fault expansions. We briefly introduce the history of use of real-time GNSS processing in the rapid estimation of the coseismic finite fault model. Additionally, we discuss our recent trials on the estimation of quasi real-time tsunami inundation based on real-time GNSS data. Obtained results clearly suggest the effectiveness of real-time GNSS for tsunami inundation estimation as the GNSS can capture fault expansion and its slip amount in a relatively accurate manner within a short time period. We also discuss the future prospects of using real-time GNSS data for tsunami warning including effective combination of different methods for more reliable forecasting.

*J. Disaster Res.*, Vol.13 No.3, pp. 453-459, 2018.

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