Semi-automated bathymetry using Sentinel-2 for coastal monitoring in the Western Mediterranean.

•A robust method applied to derive high-accuracy bathymetry from Sentinel-2 images.•The capacity of SDB models for assessing morphodynamics changes was confirmed.•The composited and switching models surpassed the standard single-ratio model.•The method retrieved depths in the presence of Posidonia oceanica meadows up to 14 m.•The satellite-derived maps reproduced the bathymetric patterns very accurately.