A Comparison of Digital Photogrammetric and Lidar High Resolution Digital Elevation Models of Bolivar Peninsula, Texas, USA

High resolution orthophotographs and digital elevation models (DEMs) could be used for the geo-spatial analysis of dynamic coastal environments. Although techniques such Light detection and ranging (LiDAR), Synthetic Aperture Radar (SAR) has been developed, the advent of low cost digital photogrammetry offers a relatively low cost solution to the generation of high resolution DEMs and orthophotographs with sub-centimeter accuracy. This study was conducted to investigate the applicability of digital photogrammetrically derived DEMs and orthophotographs to visualize and analyze dynamic coastal environments, and to test the accuracy of these DEMS with that of LiDAR DEMS of Bolivar Peninsula. The digital photogrammetric DEM was generated using ERDAS Imagine Leica Photogrammetric Suite 9.2, and the comparison between the LiDAR and photogrammetric DEMs was carried out through approaches such as comparison of selected LiDAR and photogrammetric DEM test points to differentially corrected global positioning satellite (GPS) data, subtraction of the LiDAR DEM from photogrammetrically derived DEM, and by analyzing the variance in a moving 3x3 pixel window applied to each DEM. In addition, the 3-D visualization using 3-D views and fly-through movies produced with ERDAS Imagine Virtual GIS system were used to assess the spatial consistency and overall precision and accuracy of the DEMs.