Fig.1 The study area (Gifu) locates at the central part of Japan. There are 5 meteological observation stations (blue) and 52 GPS stations (red) in and around it. Terrain height of the study area is from 0m to 2,700m, and 0m to 1,600m in JERS-1 SAR interferograms. Mountains are covered with conifer or broadleaf trees.	Fig.2 Relationship between the height and differential GPS zenith water vapor delay corresponding to JERS-1 InSAR observation times. Dependency on the height is observed as expected. However, small value of R^2 numbers mean that its contribution is small and suggest that local variations are significantly large (60% to 90%).