Assessment land subsidence variation along the north coast of Java, Indonesia, base on Ina-CORS

Land subsidence along the northern coast of Java, Indonesia, represents a critical geohazard due to its substantial socioeconomic impacts, particularly the exacerbation of coastal flooding and structural damage. Quantification of spatial and temporal variability in subsidence rates is imperative for effective mitigation strategies. This study aimed to analyze these patterns using precise geodetic observations. Daily GNSS data collected from five stations of the Ina-CORS network (Tegal, Pekalongan, Semarang, Jepara, and Rembang) were rigorously processed using GAMIT/GLOBK software. The results demonstrate heterogeneous land subsidence rates, with Semarang (−89.08 mm/yr), Pekalongan (−78.84 mm/yr), and Tegal (−20.33 mm/yr) exhibiting the highest subsidence rates. In contrast, Jepara and Rembang CORS stations remained relatively stable, indicating the influence of localized factors on the deformation mechanism.