[H-DS09] Human environment and disaster risk

[HDS09-P13] Detection of landslide surface deformation along Tamakoshi River, Nepal using PALSAR-2 interferometry images

Nozomi Jyoke², *Hiroshi, P. Sato¹ (1.College of Humanities and Sciences, Nihon University, 2.Student, College of Humanities and Sciences, Nihon University)

Keywords:SAR, PALSAR-2, landslide, Nepal

We have rainy and dry season in July-August and September-May in Nepal, respectively. Gomi et al. (2022) revealed that there are differences of landslide surface deformation between rainy and dry seasons. in Barpak, Nepal. In this study, along Tamakoshi River, Nepal, the E and W slope sites on the W and E river bank and the E slope site on the W tributary of the river were focused and the slope defomations were detected using time-series ALOS-2/PALSAR-2 interferometry images. The 11 images were produced observed between 15 Nov. 2014 and 11 Mar. 2023, and deformation amounts along LoS (line of sight) and the average deformation rate per year was calculated in rainy and dry season among the three slope sites, respectively. As a result, remarkable uplift and subsidence amounts were observed on the surfaces along 400-800m in each slope site. Furthermore, it was found that deformation rate of 230 mm/yr in rainy season was farster than that of 140 mm/yr in dry season.

Reference:
Gomi K, Sato HP, Usami S, Yagi H (2022): Detection of landslide surface deformation in Barpak, Nepal using time-series InSAR images. DOI https://doi.org/10.3313/jls.59.8