We present outcomes of our collaborative research between tsunami engineering laboratory, Tohoku University and the Willis Research Network (WRN) on global tsunami risk assessment since 2010. First we assessed tsunami hazards in Indian Ocean and west Pacific from major earthquakes based on historical records. After the 2011 Japan tsunami, various kind of fragility functions were developed for human casualty, buildings, marine vessels, etc based on the actual data. Especially, detailed tsunami hazard assessments were performed in many areas using fine bathymetry and topography data all over Japan including hazards from the worst case tsunamigenic earthquakes provided by central government and local governments in Hokkaido, Japan Sea and Nankai Trough. These results from the detailed hazard and vulnerability assessment were used for detailed tsunami risk in Japan. The Willis’s Japan tsunami model was then first released in December 2014. The model have been updating based on the updated or revised tsunami sources model and fragility functions. Detailed tsunami hazards from potential tsunami events in the Bay of Bengal, South China Sea and some parts of Indonesia were also performed in 2014. In October 2016, our contribution on the historical and future tsunami hazard assessment in global scale based on historical records over the last 400 years was conducted as an activity to increase tsunami awareness as part of World Tsunami Awareness Day. The current activities are to extend the target areas in Japan to Okinawa and assessing disaster risk reduction based on the present and planned tsunami countermeasures. We present the outcomes of the collaborative research done since 2010 by the Tsunami Engineering Laboratory of Tohoku University and the Willis Research Network (WRN) on global tsunami risk assessment. First, we assessed, based on historical records, the tsunami hazards in the Indian Ocean and western Pacific from major earthquakes. Since the 2011 Japan tsunami, various kinds of fragility functions have been developed for human casualties, buildings, marine vessels, etc., based on the actual data. Detailed tsunami hazard assessments have been performed in many areas of Japan using fine bathymetry and topography data from all over Japan, including data on hazards from the worst-case tsunamigenic earthquakes. These data have been provided by the Cabinet Office, Japan. The results from the detailed hazard and vulnerability assessments were used for detailed tsunami risk assessments in Japan. The Willis Japan tsunami model was then released in December 2014. The model has been updated based on the updated or revised tsunami source model and fragility functions. Detailed tsunami hazards from potential tsunami events in the Bay of Bengal, South China Sea, and some parts of Indonesia were also performed in 2014. In October 2016, our contribution to the historical and future tsunami hazard assessment on a global scale based on historical records over the last 400 years was conducted as an activity to increase tsunami awareness as part of World Tsunami Awareness Day. The current activities are to extend the target areas in Japan to Okinawa and to assess the disaster risk reduction based on the present and planned tsunami countermeasures.

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