[STT48-P11] PALSAR-2 InSAR image production using 5m- and 10m-resolution Digital Elevation Model in Northern Nagano Prefecture, Japan
Keywords:ALOS-2, InSAR, Landslide
InSAR images were produced using ALOS-2/PALSAR-2 data, taken in the study area of Northern Nagano Prefecture, Japan. These data were taken between 9 Dec 2014 and 30 Jan 2018 from descending orbit, right look (path19, frame 2880), and processed at the look of 8 by 8 in both range and azimuth direction. In processing the data, software RINC 0.39 (Ozawa et al., 2016) were used.In the production of the InSAR images, as a trial, three kinds of Digital Ellipsoidal Height Model, DEHM (Tobitaet al., 2005) were used for eliminate topographic effect. This is because finer resolution of DEHM is expected to give good coherence of InSAR image than coarser one.
Type I DEHM was produced from 5m DEMs (DgitalElevation Models) and Japanese Geoid height data 2011 (Miyahara et al., 2014), published by GSI of Japan. In the area where 5m DEMs are not published, 10m DEMs were used and interpolated into 5m resolution.
Type II DEHM was produced from 10m DEMs. In the area where 5m DEMs are published, these data were resampled into 10m resolution. Japanese Geoid height data 2011 was also used.
Type III DEHM was produced from only 10m DEMs, and EGM96 was used as geoid height data.
As a result, it was found that Type III DEHM tends to give best coherence of InSAR image. In the future it will be considered that how well the Type III DEHM works to detect landslide surface deformation in the study area. This study used PALSAR-2 data provided by JAXA, in the special study (B) in 2017, ERI, Tokyo Univ. and Type III DEHM was also provided in the special study.
References
Miyahara et al., 2014, http://www.gsi.go.jp/common/000099005.pdf
Ozawa et al., 2016, doi: 10.1186/s40623-016-0563-5.
Tobita et al., 2005, http://www.gsi.go.jp/common/000024818.pdf
Type I DEHM was produced from 5m DEMs (DgitalElevation Models) and Japanese Geoid height data 2011 (Miyahara et al., 2014), published by GSI of Japan. In the area where 5m DEMs are not published, 10m DEMs were used and interpolated into 5m resolution.
Type II DEHM was produced from 10m DEMs. In the area where 5m DEMs are published, these data were resampled into 10m resolution. Japanese Geoid height data 2011 was also used.
Type III DEHM was produced from only 10m DEMs, and EGM96 was used as geoid height data.
As a result, it was found that Type III DEHM tends to give best coherence of InSAR image. In the future it will be considered that how well the Type III DEHM works to detect landslide surface deformation in the study area. This study used PALSAR-2 data provided by JAXA, in the special study (B) in 2017, ERI, Tokyo Univ. and Type III DEHM was also provided in the special study.
References
Miyahara et al., 2014, http://www.gsi.go.jp/common/000099005.pdf
Ozawa et al., 2016, doi: 10.1186/s40623-016-0563-5.
Tobita et al., 2005, http://www.gsi.go.jp/common/000024818.pdf