Beyond Population Decline: A Dual Tracking Framework of Smartphone GPS and Resident Registry for Disaster Recovery in Coastal Japan

Abstract

This study examines post-disaster population dynamics in Wajima City, Ishikawa Prefecture, following the 2024 Noto Peninsula Earthquake. By comparing smartphone-based GPS mobility data and resident migration data from the Basic Resident Registry, we identify a divergence between visitor inflow and sustained resident outflow. A dual tracking approach is introduced, visualizing both trends and their interaction using system thinking and causal loop diagrams (CLDs). Our analysis reveals structural gaps between surface-level recovery and long-term demographic decline. This framework offers a transferable methodology for assessing disaster recovery in coastal regions worldwide.

Keywords: smartphone GPS, Basic Resident Register, disaster recovery, human mobility, causal loop diagram

DOI: 10.54941/ahfe1006845