Comparison of Topographical Data and Orthophoto by Aerial Laser Measurements and Satellite Image

Abstract

To extract the topographical characteristics of newly occurring slope collapses and landslides, it is necessary to perform geographic analysis based on topographical data before such calamities occur. However, topographical data are often not collected in such situations. In contrast, satellite images are regularly captured and can be used to obtain topographical data before such calamities occur. In this study, we compared the topographical data and orthophoto obtained from satellite images and aerial laser measurements of the plains and mountains in Hiroshima and Hyogo prefectures. From the analysis, it was observed from both the topographical data and orthophoto that the plain area had a residual of approximately 2 m. In contrast, some areas in the mountainous region had residuals of approximately 2 and 9 m.