Changes of nighttime lights in the Guanzhong region of China during the COVID-19 pandemic

The severe impact of the COVID-19 pandemic on socio-economic development has prompted an exploration of its effects on urban activities. Using December 2021 as a case study during the pandemic in the Guanzhong region of China, this paper conducts a multiscale analysis of the area using NPP-VIIRS monthly composite data. The results indicate that during the pandemic, more than 80% of areas in Xi'an, Weinan, and Baoji showed a downward trend in nighttime lights, with Xi'an being the most severely affected but also recovering the fastest, while Tongchuan was the least affected and had the slowest recovery. The spatiotemporal evolution pattern in the Guanzhong region exhibited a northwest-to-southeast directionality, with changes in the standard deviation ellipse area primarily driven by changes in urban lighting in central cities. This study further verified that the Remote sensing of nighttime lights effectively reflects changes in urban lighting and indicated the significance in assessing the impact of policy implementations during major emergencies.