An Integrated Simulation of Tsunami Hazard and Human Evacuation in La Punta, Peru

Abstract

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.

The Role of Built Environment's Physical Urban Form in Supporting Rapid Tsunami Evacuations: Using Computer-Based Models and Real-World Data as Examination Tools

“…The first one is an agent-definition file that sets up the overall quantity of agents (28,296 for the night-time scenario and 53,743 for the rush-hour case, according to SECTRA, 2016) and their individual characteristics. These are: (1) a randomly assigned location within the streets and open spaces of the analysis area; (2) a walking speed for every agent, randomly assigned based on Viña del Mar's population age distribution (Mas et al, 2013) on every agent's evacuation direction during the computation in order to reflect the incertitude that each evacuee will follow the route to the shelter, which may be provoked by lack of knowledge or guidance, congestion or damage along the road; and (4) a crowd potential parameter which makes the agent follow the direction in which there are other evacuees. In turn, the second input feature for the model is a file that describes the evacuation zone and its accessible (i.e., streets and open spaces) and non-accessible (i.e., buildings) areas.…”

“…The first one was the slope effect on the agents' speed, i.e., the steeper the gradient, the slower the movement (for both uphill and downhill movement), according to Tobler's exponential hiking function (Tobler, 1993). The second new parameter for the model was a delayed or slow starting time for each evacuee, reflecting the fact that a slow evacuation (fully triggered only by the imminent threat of an arriving tsunami) can be the predominant behavior during an emergency (Mas et al, 2013). To randomly assign a starting time to each agent, a Rayleigh cumulative distribution was considered, with a mean departure time of 10 min after the beginning of the tsunamigenic earthquake, which reflects the common time gap between the earthquake occurrence and the tsunami warning as released by ONEMI.…”

Recent Advances in Agent-Based Tsunami Evacuation Simulations: Case Studies in Indonesia, Thailand, Japan and Peru

“…9). The authors used the agent-based tsunami evacuation model (MAS et al 2013a) to investigate a tsunami inundation and the resident evacuation behavior.…”

“…A detailed description of the assumptions and constraints for each simulated case can be found in MAS et al (2013a). In addition to the casualty estimate, more detailed and interesting information is found for the TEBs regarding their capacities and the numbers of evacuees that arrived.…”

“…The future of tsunami evacuation research, as seen by the authors, concerns the comprehensive geophysics of tsunamis and the physical and psychological traits of the evacuees, all of which would be built into an integrated modeling technique. Efforts to integrate tsunami simulations and social simulations using agent-based modeling (MAS et al , 2013a and to use supercomputers (WIJERATHNE et al 2013) to bridge gaps between geoscience and social science connect risk assessments with risk management. With these tools, evacuation issues can be understood in a more comprehensive manner.…”