Recent Advances in Coastal Survey Techniques: From GNSS to LiDAR and Digital Photogrammetry - Examples on the Northern Coast of France
Résumé
The aim of this chapter is to document the evolution of surveying techniques used for monitoring changes in morphology of beaches and coastal dunes in northern France, beginning with GNSS surveys in the 1990s, followed by airborne topographic LiDAR surveys since 2008, and high-resolution digital photogrammetry data collected by an UAV during recent years. Digital Terrain Models (DTMs) derived from the data obtained from the different techniques were used for monitoring coastal changes, including shoreline evolution, and for computing sediment volume changes across the foreshore and the coastal dunes at different time and spatial scales. A comparison of the results obtained using these different techniques and of their accuracy will be carried out to assess the pro and cons of each surveying technique.