Influence of residents’ cognition of their local environment on evacuation behavior from tsunamis: A case study of Onjuku, Chiba prefecture

This paper focuses on the effects of residents’ cognition of their local environment on evacuation behavior in the event of a tsunami. We conducted questionnaire surveys and a sketch map survey in the coastal area of Onjuku, Chiba Prefecture. The results revealed the following: (i) evacuation implementation was influenced by cognition of the terrain around their home (the elevation from sea level and/or the distance from the sea) although it was not always correct; (ii) although reasons for choosing evacuation place were different from place to place, main reasons were the location (proximity and ground height) and the sense of safety; and (iii) some improper evacuation route choices (approached the sea, crossed rivers or decreased in elevation) were caused by “distorted” cognitive maps. These results suggest that understanding residents’ cognition is important in developing effective mitigation measures against tsunamis. The tsunami evacuation planning should include informing residents of the actual structure of the town and the appropriate direction for evacuation.