Analyzing Urban Tsunami Evacuation Through Evacuees’ Spatial Behaviors

Evacuation is the most effective method to save human lives in case of a tsunami. Yet, challenges remain in understanding the populations’ actual spatial behaviors during emergencies. In this chapter, we work with a mobile-call details records database of 16,753 users to analyze the spatial behaviors of evacuees during a tsunami emergency in Viña del Mar, Chile, and to compare them with the existing protocols in the city. Our findings demonstrate that several people moved in the wake of the tsunami warning, probably because of evacuation. Moreover, we could map these displacements to find out which areas of the city gathered most departures and most arrivals. We also confirmed that many persons in the exposed zones did not follow the recommendations of the existing evacuation protocol. A large percentage of them (roughly 37%) did not move at all, while other people did not proceed to their closest shelter. Lastly, a significant group crossed the bridges over the Marga-Marga Creek (a likely tsunami penetration path). These findings show that the city’s emergency stakeholders should assess more carefully current evacuation plans and promote evidence-based education for tsunami response.