Monitoring House Vacancy Dynamics in The Pearl River Delta Region: A Method Based on NPP-VIIRS Night-Time Light Remote Sensing Images

TLDR

Urban spatial interaction links cities into continuous networks but also creates differentiation and negative impacts, making unbalanced development—measured by housing vacancy rates—critical to monitor across regions. The study aims to estimate district‑level housing vacancy rates in the Pearl River Delta using NPP‑VIIRS night‑time light and Landsat 8 imagery, track their spatial‑temporal dynamics, and highlight the need for more precise data and advanced techniques to improve estimation accuracy. The authors estimate district‑level HVRs by combining NPP‑VIIRS night‑time light with Landsat 8 optical imagery and validate the estimates against sampled HVRs, enabling tracking of spatial‑temporal dynamics across the PRD. The analysis reveals overall declining HVRs in the PRD but identifies speculative and irrational real estate investment on the west bank and in isolated districts, while rising vacant pixel proportions in most cities signal increasing development that warrants closer supervision.

Abstract

Urban spatial interaction integrates cities into closely related urban network systems in continuous urban regions. However, it also brings differentiation and has mutual negative impacts between each location. Unbalanced development is one such impacts and needs closely monitoring. The housing vacancy rate (HVR) in a continuous urban region is an important index in the unbalanced development of a continuous urban region since it indicates the uneven distribution of population and investment across cities. This study uses NPP-VIIRS NTL data and Landsat 8 OLT images to estimate HVRs at the district level. Additionally, this study tracks the spatial–temporal dynamics of HVR distributions in the Pearl River Delta (PRD) region. The comparison between the sampled HVRs and estimated HVRs verifies the effectiveness of the estimated HVRs in identifying dynamic changes in HVRs. This study has found that although overall decreasing HVRs are observed in the PRD, speculations and irrational real estate investment exist in cities on the west bank of the Pearl River Estuary and in some isolated districts in other cities. Furthermore, increasing proportions of vacant pixels in most cities indicate rising real estate development, requiring further supervision. This study suggests that more precise data and advanced techniques could help to improve the accuracy of the estimation techniques.