Investigation of Tsunami Propagation Characteristics in River and on Land Induced by the Great East Japan Earthquake 2011

Abstract

The Great East Japan Earthquake of March 11, 2011 generated a massive tsunami wave that severely damaged coastal areas of Japan. Furthermore, the wave propagated into rivers, causing damage upstream far from shore. Videos recorded during this tsunami event were collected and analyzed to estimate the celerity of tsunami propagation in river and on the land. The result shows good comparison with estimation based on theoretical approaches that use water level measurement data. It was found that the tsunami celerity in river is approximately 25–30 km/h, and moved upstream with gradual deceleration. However, wave celerity on land was decreased significantly due to debris and dominant ground friction. The propagation trend in river mainstream and floodplain behaves differently in the location where the mainstream is not parallel to the embankment. Tsunami discharge and velocity in a river induced by tsunami wave were estimated based on continuity equation using the measured water level variation along the Sunaoshi River. The maximum estimated discharge is approximately 152 m3/s with the maximum velocity of 1.4 m/s.

River channel evolution and tsunami impacts recorded in local sedimentary archives – the ‘Fiume Morto’ at Ostia Antica (Tiber River, Italy)

“…From recent research, it is well‐known that the inland propagation of tsunami or tsunami‐like waves may especially occur in the course of rivers (e.g. Adityawan et al ., ; Japan tsunami). Along the Mazaro River in south‐western Sicily, a 2014 meteorological event induced ca 1·5 m high tsunami‐like waves that advanced nearly 1·2 km upstream, flooding the local promenade (Šepić et al ., ).…”

Evaluation of Celerity and Velocity for Tsunami Propagation Into Rivers

“…The tsunami wave in rivers arrived early at the river upstream area. The difference of tsunami impact on land and rivers can be seen clearly (Adityawan et al, 2012). The tsunami intrusion into rivers is also an important tsunami phenomenon that is closely related to secondary disaster such as the tsunami infiltration and overflow over the river embankment into an unexpected area in the upstream part of the river.…”

Effects on river macroinvertebrate communities of tsunami propagation after the 2011 Great East Japan Earthquake

“…The energy generated in the ocean is transformed into kinetic energy in shallow waters, resulting in high-velocity reverse water flow in rivers. Based on video images taken during the 2011 tsunami on the Sendai Plane, Adityawan et al (2012) estimated that the wave velocity reached 25-30 km h À1 (=0.69-0.83 m s À1 ) between 1.5 and 4.5 km upstream of the river mouth, with a small reduction further upstream along the corridors. In land areas, the velocity displayed a distinct reduction with distance from the shoreline due to resistance to the flow on the ground (e.g.…”