A national-scale assessment of land subsidence in China’s major cities

Abstract

China’s massive wave of urbanization may be threatened by land subsidence. Using a spaceborne synthetic aperture radar interferometry technique, we provided a systematic assessment of land subsidence in all of China’s major cities from 2015 to 2022. Of the examined urban lands, 45% are subsiding faster than 3 millimeters per year, and 16% are subsiding faster than 10 millimeters per year, affecting 29 and 7% of the urban population, respectively. The subsidence appears to be associated with a range of factors such as groundwater withdrawal and the weight of buildings. By 2120, 22 to 26% of China’s coastal lands will have a relative elevation lower than sea level, hosting 9 to 11% of the coastal population, because of the combined effect of city subsidence and sea-level rise. Our results underscore the necessity of enhancing protective measures to mitigate potential damages from subsidence.

Potential and Influencing Factors of Urban Spatial Development under Natural Constraints: A Case Study of the Guangdong-Hong Kong-Macao Greater Bay Area

“…At the overall level of the GBA, silty sand content is the primary factor affecting spatial heterogeneity in urban areas. Similar to Zurui Ao et al (2024)'s findings, the geological structure beneath cities plays a crucial role in urban subsidence, impacting surface stability and leading to structural damage [39]. This underscores the importance of soil conditions in urban development at the Bay Area level.…”

Deformation Monitoring Based on SBAS-InSAR and Leveling Measurement: A Case Study of the Jing-Mi Diversion Canal in China

“…In addition to the groundwater level discussed in this article, there are many other factors that affect subsidence. For example, the construction of high-rise buildings [ 46 , 47 ] and vibrations caused by subway operations [ 48 ]. All of these have stressed the city and exacerbated subsidence.…”