Comparative analysis of mobile space statistics data and questionnaire survey data to detect tsunami evacuation behavior: Case of Fukushima earthquake tsunami in Ishinomaki city and Watari town, Miyagi prefecture

This paper investigates whether it is possible to determine shelter locations and congestion spots at the time of an event, by resorting to the recently anticipated use of mobile space data at the time of a disaster. This study focused on the earthquake and the resulting tsunami that occurred off the coast of Fukushima Prefecture on November 22^nd, 2016. We verified whether it is possible to identify congestion spots and shelter locations by comparing with the results of a questionnaire survey conducted in a previous study on evacuation behavior at the time of the occurrence of earthquakes and tsunamis. As a result, we found that it is difficult to determine evacuation behaviors from the data, as raw mobile space data extracted several hours after the tsunami event only gave information on where spots’ populations ordinarily converge to. We were able to determine the locations where populations gather by taking into consideration time-based differences between the raw data obtained. It, however, proved difficult to obtain a good determination of congestion spots.