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At 14:46 local time on March 11, 2011, a magnitude 9.0 earthquake occurred off the coast of northeast Japan. This earthquake generated a tsunami that struck Japan as well as various locations around the Pacific Ocean. With the participation of about 300 researchers from throughout Japan, joint research groups conducted a tsunami survey along a 2,000 km stretch of the Japanese coast. More than 5,200 locations have been surveyed to date, generating the largest tsunami survey dataset in the world. The inundation height and run-up height were surveyed by laser, GPS, and other instruments, and the tidal correction has been accurately adjusted using a tidal database and a numerical simulation for Tohoku, an area where tide gauges were destroyed by the tsunami. Based on the survey dataset, the regional and local scale analyses were conducted to understand the basic characteristics of this event. Maximum run-up heights greater than 10 m are distributed along 500 km of coast in direct distance. The affected area of this event was several times larger than historically recorded in Tohoku. The mean inundation height in the southern Sanriku region is 10-15 m and there are several peaks of inundation along the coast from the northern to middle part of Sanriku. [ABSTRACT FROM AUTHOR]

The behavior of the 2011 Tohoku earthquake tsunami in Tokyo Bay and its resultant damage to the coasts are studied using a field survey, an analysis of observed tsunami wave profiles and numerical hindcasting using FVCOM and Delft3D-Flow. The field survey reveals that the tsunami caused several fishery ports to overflow, and unexpectedly large inundation and run-up heights of 2.84 m and 2.91 m were recorded in Funabashi Fishery Port and Shin-Futtsu Fishery Port, respectively. Examining the observed tsunami wave profiles, the tsunami wave entered the bay with a maximum height of approximately 0.9 m for the second wave and a period of approximately 60 min, propagating along the major axis of the bay with almost uniform height. Numerical hindcasting results using both the models are fairly consistent with the measurements, revealing that the tsunami wave heights are locally amplified in ports because of wave reflection, water accumulation due to their narrow and enclosed shape, and, to some extent, the harbor resonance. Heavy damage to seaweed farming was also observed, especially around the Futtsu Cape and the northern part of the Banzu tidal flat, which numerical analysis attributes to the appearance of large hydraulic resistance on seaweed net. [ABSTRACT FROM AUTHOR]

No abstract received. [ABSTRACT FROM AUTHOR]