The 2011 Great East Japan Earthquake/Tsunami was a magnitude 9.0 Mw event that destroyed most structural tsunami countermeasures. However, approximately 90% of the estimated population at risk from the tsunami survived due to rapid evacuation to higher ground or inland. In this paper, we introduce an evacuation model integrated with a numerical simulation of a tsunami and a casualty estimation evaluation. The model was developed in Netlogo, a multi-agent programming language and modeling environment for simulating complex phenomena. GIS data are used as spatial input information for road and shelter locations. Tsunami departure curves are used as the start time for agents deciding to evacuate in the model. Pedestrians and car drivers decide their own goals and search for a suitable route through algorithms that are also used in the video game and artificial intelligence fields. Bottleneck identification, shelter demand, and casualty estimation are some of the applications of the simulator. A case study of the model is presented for the village of Arahama in the Sendai plain area of Miyagi Prefecture in Japan. A stochastic simulation with 1,000 repetitions of evacuation resulted in a mean of 82.1% (SD=3.0%) of the population evacuated, including a total average of 498 agents evacuating to a multi-story shelter. The results agree with the reported outcome of 90% evacuation and 520 sheltered evacuees in the event. The proposed model shows the capability of exploring individual parameters and outcomes. The model allows observation of the behavior of individuals in the complex process of tsunami evacuation. This tool is important for the future evaluation of evacuation feasibility and shelter demand analysis.

Tsunami fragility (fragility curve, or fragility function) is a new measure, we propose, for estimating structural damage and fatalities due to tsunami attack, by integrating satellite remote sensing, field survey, numerical modeling, and historical data analysis with geographic information system (GIS). Tsunami fragility is expressed as the structural damage probability or fatality ratio related to hydrodynamic features of tsunami inundation flow, such as inundation depth, current velocity and hydrodynamic force. It expands the capability of estimating potential tsunami damage in a quantitative manner.

The Lisbon Earthquake of November 1, 1755, one of the most catastrophic events that has ever occurred in Portugal, Spain, or Morocco, caused severe damage and many casualties. The tsunami generated by this earthquake is well documented in historical accounts, it was reported throughout the North Atlantic Ocean, as it reached not only Portugal, Spain, and Morocco, but also the Madeira and Azores Archipelagos, England, Ireland, and the Caribbean. In spite of the importance of this event, the source of the tsunami remains unknown. In this paper, the authors reevaluate some of the historical tsunami travel times obtained by previous authors. Based on these times, wave ray analysis is used to determine the location of the tsunami source area. These results, combined with turbidites obtained by previous authors at the Tagus and Horseshoe Abyssal Plains, lead to the conclusion that the source of the 1755 Lisbon Tsunami could be located in the area of the Gorringe Bank. Then, a hydrodynamic simulation is carried out with this area presupposed as the source. The numerical model results provide good agreement when compared with both historical and sedimental records. However, in the past, the Gorringe Bank has been dismissed as the source of this tsunami for several reasons. Therefore, these issues are discussed and discredited. As a consequence of all these facts, it can be concluded that the origin of the 1755 Lisbon Earthquake and Tsunami could be located in the area of the Gorringe Bank.

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The 2011 Great East Japan earthquake and tsunami was a magnitude 9.0 Mw event that destroyed most structural tsunami countermeasures. However, approximately 90% of the estimated population at risk from the tsunami survived due to a rapid evacuation to higher ground or inland. Thus, tsunami evacuation is the most effective measure to reduce casualties. In this paper, we applied a new developed evacuation model integrated with the numerical simulation of tsunami for casualty estimation. This tool is to support decisions in disaster management and disaster prevention education. The model was developed in NetLogo, a multi-agent programming language and modeling environment for simulating complex phenomena. Geographic Information Systems (GIS) datasets are used as spatial input information for road and shelter locations. The TUNAMI model of Tohoku University is used for the integration of tsunami numerical simulation results. In this paper, the study is performed in a tsunami threatened urban area of Callao, Peru, called La Punta. Results show the various contributions of the model to disaster management and scenario analysis. Among the contributions are the casualty estimation in a tsunami risk area and the analysis of the spatial distribution of vertical evacuation shelters.