Verification Example of Wide-Area Ground Subsidence Observation Using Ground Subsidence Observation Results from Leveling Surveys and Satellite SAR Time-Series Analysis Results

Abstract

This case study examines the differences between ground subsidence measurements taken from space (interferometric SAR analysis results) and measurements taken on land (leveling survey results). The target area is the Nobi Plain, spanning Aichi, Gifu, and Mie prefectures, with an area of approximately 40 km north-south and 30 km east-west. This case study uses interferometric SAR analysis results from Sentinel-1 satellite data, interferometric SAR analysis results from ALOS-2 data loaned by the Geospatial Information Authority of Japan, and leveling survey observation results compiled by the Tokai Three Prefectures Ground Subsidence Survey Association. The verification period is five years, from 2016 to 2021. The verification results showed that the interferometric SAR analysis results of the SBAS method at 30 m from the Sentinel-1 satellite were in good agreement with the leveling survey results. In the future, it is desirable to conduct comparative verification of the interferometric SAR analysis results of the SBAS method at 30 m from the ALOS-2 satellite and the leveling survey results.