Monitoring Intertidal Bars and 3D Coastal Mapping Using an Automatic Algorithm on a Lidar Dataset

Sandy beaches play an important role for economic and recreational activities as well as for coastal protection. Storm impact and recovery involve complex dynamic processes from short to longer-term. These result in a broad range of morphological change which can be assessed from remote sensing such as airborne LiDAR (Light Detecting and Ranging) system. This study monitors the response and recovery of a sandy multi-barred beach after a severe storm. A new algorithm for automated bar extraction developed in Python is applied to the digital surface models of pre-, immediately after storm and 2 months after the event. The severe storm from 8-12/02/2020 caused erosion of the backshore and dunefoot as well as a significant re-arrangement of the intertidal bar-through system. The findings are of critical importance in improving our knowledge as well as forecasting coastal evolution and future hazards.