Monitoring of surface subsidence in the main urban area of Nanjing using the integration of PS and DS methods

To precisely invert urban surface deformation fields, this study used DS - InSAR with distributed scatter (DS) targets. We conducted time - series analysis on 73 ascending Sentinel - 1A satellite images (from February 2020 to January 2025) to get the subsidence rates and cumulative subsidence amounts in Nanjing's main urban area. Results show that ground subsidence in Nanjing is uneven, mainly near Pukou District in Jiangbei, with a maximum subsidence rate of - 37 mm/a and maximum cumulative subsidence of - 220 mm. These findings can support Nanjing's urban planning and construction