Terrestrial laser scanner applied to fluvial geomorphology

Abstract Terrestrial laser scanner (TLS) offers an unprecedented combination of sub-cm resolution, mm precision and survey extent that uniquely captures the geometry of individual pebbles and allows the spatial variability of channel evolution to be quantified precisely. Data processing can, however, be challenging, and the full scientific potential of fluvial 3D datasets remains arguably untapped. This chapter is an introduction to using TLS to solve fluvial geomorphology problems, synthesizing data acquisition, processing methods, and application examples. It covers practical aspects of field acquisition and addresses the respective benefits of TLS and structure from motion (SfM). Three-dimensional (3D) point cloud processing methods involved in data registration, vegetation classification, and spatial analysis are presented. Processing of repeat surveys and change detection methods are synthesized and the choice of raster-based or 3D point cloud differencing methods discussed in the context of fluvial processes and dynamics.