2DH-Quantification of Surf Zone Bathymetry from Video

Information on the actual state of the nearshore zone – in terms of topographic variability, surface waves, and circulation patterns is crucial in many naval and civilian applications. Spatial scales of interest generally span distances on the order of hundreds of meters to a few kilometers. Obtaining this information form in situ measurements or model predictions alone is not feasible. This paper presents results of the first efforts in assimilating high-resolution video observations of the surf zone with a 2DH morphological model to map 3D bathymetry in the surf zone. Two pilot applications demonstrate the model's potential, returning a realistic rip channelled beach topography at Monterey (CA, USA) and preserving the characteristic bar-trough configuration at Egmond (NL) throughout the entire 9 month simulation period. Being fully embedded in the Delft3D modelling system, the assimilation model can be combined with any regular hydrodynamic or morphological model run. This sophisticated use of highresolution video observations in combination with a 2DH morphological model opens the door towards the nowcasting of nearshore bathymetric