Volume IV-3/W1
ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., IV-3/W1, 9-16, 2019
https://doi.org/10.5194/isprs-annals-IV-3-W1-9-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., IV-3/W1, 9-16, 2019
https://doi.org/10.5194/isprs-annals-IV-3-W1-9-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

  01 Mar 2019

01 Mar 2019

INTEGRATING MULTI-TEMPORAL SAR IMAGES AND GPS DATA TO MONITOR THREE-DIMENSIONAL LAND SUBSIDENCE

H. Ito1, J. Susaki1, and T. Anahara2 H. Ito et al.
  • 1Graduate School of Engineering, Kyoto University, C1-1-206, Kyotodaigakukatsura, Nishikyo-ku, Kyoto 615-8540, Japan
  • 2Earth Observation Research Center, Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505 Japan

Keywords: land subsidence, PSI, synthetic-aperture radar (SAR), leveling, GPS

Abstract. Synthetic aperture radar (SAR) is an effective means of monitoring land subsidence, and differential interferometric SAR (DInSAR) is commonly used to acquire the necessary data. In particular, persistent scatterer interferometry (PSI) can be used to measure land subsidence accurately over a wide area from multi-temporal SAR images. However, the estimated displacement is obtained only in the radar line-of-sight (LOS) direction, making it necessary to develop a method for measuring three-dimensional displacements by combining multidirectional observations. Therefore, we propose herein a method for estimating three-dimensional displacement velocities by combining the results from PSI and geodetic deformation measurements, namely, Global Positioning System and leveling data. We apply the least-squares method to Kansai International Airport in Japan by using 13 ALOS-2/PALSAR-2 ascending images from 2014 to 2018 and 17 ALOS-2/PALSAR-2 descending images from 2015 to 2018. In validation, the rootmean- square errors are 14, 16, and 14 mm/year for the east–west, north–south, and vertical components, respectively, showing that combining PSI results and geodetic deformation measurements is effective for monitoring land subsidence.