Research on the estimation of the real-time population in an earthquake area based on phone signals: A case study of the Jiuzhaigou earthquake

After an earthquake, the goal of emergency rescue work is to minimize the number of casualties and save lives. The most important initial task is the rapid assessment of the number of earthquake casualties. At present, the rapid assessment of casualties relies primarily on census data rather than real-time population data in an earthquake area. Features of the census data, such as their low accuracy and time lag, can easily cause large errors in the assessment result; thus, the assessment result cannot always reflect the actual situation in an earthquake area. In this paper, we use phone signal data to construct a population density model and estimate the real-time population in a seismic area. The results show that the estimated population is consistent with the actual data in the study area. Finally, we obtain a real-time population distribution map of the study area. The real-time distribution of the population is consistent with the actual situation based on the economic and social development of the study area. The population in an urban area is relatively dense, whereas that in a rural area is less dense. The results show that phone signal data can play a useful role in estimating the real-time population when an earthquake occurs and can be used to support earthquake emergency rescue work.