Dynamic assessment of the COVID-19 lockdown in the Xinjiang region using night-time light remote sensing

ABSTRACT

China used to have the world’s most stringent prevention policies during the COVID-19 pandemic. The strict lockdown in Xinjiang region in 2022 was considered to be the longest in the process of COVID-19 pandemic prevention. Therefore, we examined the dynamic effects of the COVID-19 lockdown in Xinjiang region using night-time light data. The findings showed that before the outbreak of COVID-19, the night-time light in Xinjiang region still maintained a significant growth. However, after the lockdown of COVID-19 in August 2022, the night-time light showed a significant decrease, especially in August. Urumqi's night-time light decreased by at least 25% compared to the non-lockdown, while that in other major cities was between 5% and 15%. After the lockdown was lifted in November 2022, the night-time light in Urumqi increased by at least 50% compared to the lockdown, while that in other major cities was generally less than 30%. The regions where night-time light decreased in Urumqi were mainly within a radius of 40 km, whereas that in other cities were mainly concentrated within a radius of 6 km. The changes in statistical data and night-time light indicated that the economic activities in Xinjiang region were significantly affected by the COVID-19 lockdown.

KEYWORDS:

• Xinjiang region
• COVID-19 lockdown
• night-time light remote sensing
• spatiotemporal changes
• comparative analysis
• human activity intensity

Acknowledgement

The authors thank the editors and anonymous referees for their valuable comments on an earlier version of this study. The authors thank the Third Xinjiang Comprehensive Scientific Expedition Project and the National Natural Science Foundation of China for their support to this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The NPP/VIIRS monthly products that support the findings of this study are openly available in Earth Observation Group (EOG) at https://eogdata.mines.edu/products/vnl/.

Additional information

Funding

This work was supported by the Third Xinjiang Comprehensive Scientific Expedition Program under [grant number 2022xjkk0803] and the National Natural Science Foundation of China under [grant number 42071253].