Does China's Urban Development Satisfy Zipf's Law? A Multiscale Perspective from the NPP-VIIRS Nighttime Light Data

Currently, whether the urban development in China satisfies Zipf's law across different scales is still unclear. Thus, this study attempted to explore whether China's urban development satisfies Zipf's law across different scales from the National Polar-Orbiting Partnership's Visible Infrared Imaging Radiometer Suite (NPP-VIIRS) nighttime light data. First, the NPP-VIIRS data were corrected. Then, based on the Zipf law model, the corrected NPP-VIIRS data were used to evaluate China's urban development at multiple scales. The results showed that the corrected NPP-VIIRS data could effectively reflect the state of urban development in China. Additionally, the Zipf index (q) values, which could express the degree of urban development, decreased from 2012 to 2018 overall in all provinces, prefectures, and counties. Since the value of q was relatively close to 1 with an R-2 value > 0.70, the development of the provinces and prefectures was close to the ideal Zipf's law state. In all counties, q > 1 with an R-2 value > 0.70, which showed that the primate county had a relatively stronger monopoly capacity. When the value of q < 1 with a continuous declination in the top 2000 counties, the top 250 prefectures, and the top 20 provinces in equilibrium, there was little difference in the scale of development at the multiscale level with an R-2 > 0.90. The results enriched our understanding of urban development in terms of Zipf's law and had valuable implications for relevant decision-makers and stakeholders.