Improving the Measurement Accuracy of Three-Dimensional Topography Changes Using Optical Satellite Stereo Image Data

We describe a methodology that allows the more accurate detection and investigation of 3-D terrain changes using digital elevation models (DEMs) derived from stereoscopic pushbroom cameras on board satellites. Repeat 15-m-resolution orthorectified images and stereophotogrammetric DEMs were produced from the Advanced Spaceborne Thermal Emission and Reflection Radiometer for displacement analysis. The column and line numbers in the sensor geometry are included to each pixel. We reveal that the attitude oscillation of the satellite has a considerable effect on geometric accuracy, which is, in this paper, corrected along the scan lines of pushbroom sensors by destriping in the sensor geometry. Our results show that the distortion in DEMs is reduced by about 40% in terms of standard deviation under similar sun elevation conditions by correcting the effect of pitch and yaw oscillations. The proposed methodology was applied to the measurement of ground deformation generated by a swarm of earthquakes between September 14 and October 4, 2005, which occurred in Dabbahu, Ethiopia. We successfully detected the horizontal displacements and DEM differences with about 0.1-pixel accuracy.