Spatial analysis of population mobility in China in recent years: a study based on Baidu migration big data

The period around Chinese New Year is the most active period of national population movement in China, providing a natural experiment to examine the characteristics of population flow and interregional connections. Based on Baidu migration big data from the 2022 and 2023 Spring Festival travel rush, this study analyses over 2.7 billion population flow records from 293 prefecture-level cities and 4 municipalities over 80 days. From the perspectives of external connections and concentration levels, this study investigates the characteristics and agglomeration features of population mobility at the provincial level. This study reveals that the average daily passenger flow during the 2023 Spring Festival travel rush significantly increased compared to 2022, and the proportion of interprovincial population flow in each province also increased, indicating a rebound in the scale and openness of population mobility after the COVID-19 pandemic. Guangdong Province is the most active in terms of population mobility, attracting both domestic and out-of-province populations. Provinces with active interprovincial migration are mainly concentrated in the central and eastern regions, with all provinces in the Yangtze River Delta being major employment hubs. Interprovincial migrant populations not only have a large scale and high proportion but also diverse source regions. Central provinces such as Henan, Anhui, and Hunan are major labour exporters. Western, North, and Northeast China mainly experience intraprovincial population flow, with interprovincial mobility mostly occurring within provinces in the same region. In contrast, border provinces such as Xinjiang and Tibet have smaller population flows, are less attractive for populations from other provinces, and have lower proportions of local populations leaving, indicating a need for enhanced external connections.