Fig. 4.

Acquired image (top), simulated image (middle), and estimated topography (bottom). SAR images were described in radar coordinates; foreshortening distortion was not corrected. Topographic contours are depicted using the digital ellipsoidal height model used in this study. The yellow curve in the simulated image denotes the margin of lava dome traced in the observed image. In the estimated topography, thin curves represent contours of ellipsoidal heights, and the red circle indicates a schematic margin of lava dome. The red cross in the red circle represents the top of ellipsoid, and the attached number is its ellipsoidal height. (a) PALSAR image acquired on January 18. (b) PALSAR image acquired on January 27. (c) PALSAR image acquired on January 29. (d) PALSAR image acquired on January 30. (e) TerraSAR-X image acquired on January 31. (f) TerraSAR-X image acquired on February 1. (g) PALSAR image acquired on February 1. (h) PALSAR image acquired on February 3. See Table 1 for observation times.