High-speed rail and urban expansion: An empirical study using a time series of nighttime light satellite data in China

Transportation, especially high-speed rail (HSR), plays a key role in urban development. Although many empirical studies have substantiated the impact of HSR on urban economic outcomes, the role of HSR in urban spatial expansion is seldom empirically measured. Previous studies have shown that the improvement of transportation infrastructure and technology can promote the expansion of cities, mostly on the construction land area announced by the government. This study, which is based on high-precision calibrated nighttime light satellite images, accurately measured the impact of HSR on urban expansion. We estimated a difference-in-differences model after eliminating selection bias by propensity score matching. HSR has a positive effect on urban expansion with an elasticity of 0.12-0.13. In addition, HSR is almost twice as successful at promoting urban expansion in the underdeveloped central and western cities as in the developed eastern cities in China. Governments should consider the varying responses of cities at different levels of development when using HSR to promote urban development. For future HSR line planning in China, the governments should appropriately focus on the central and western regions in order to achieve the most efficient use of resources and balanced regional development.