Abstract
On March 11, 2011, the Great East Japan Earthquake generated huge tsunami waves, and severe devastating damages have been induced on the East Japan coastal area. Several video images taken during this tsunami event in Sendai Plane were collected and analyzed to estimate celerity of tsunami propagated into river and land area. It was found that the tsunami celerity in river attained to 25km/h to 30km/h with slow reduction in the upstream direction, whereas in the land area, celerity shows distinct reduction with distance from the shoreline due to predominant resistance on the ground. Furthermore, tsunami-induced velocity is estimated from measured water level variation along the Sunaoshi River. Temporal variation of velocity is successfully estimated along the river by applying the conservation equation.
