Implementation and validation of a 3D regional ocean model CROCO for sediment transport purposes in NW Iberian continental shelf

This study examines ocean circulation, waves, and suspended sediment transport on the high-energy, upwelling-dominated Northwest Iberian Margin. Using the 3D oceanic numerical model CROCO (v1.0) with an integrated sediment transport module, a high-resolution simulation from November 2008 to December 2009 was conducted. Coupled offline with 2D spectral wave and atmospheric models, the system was validated against in situ observational data, showing good agreement in wave field evolution and mean circulation patterns. Performance metrics demonstrate results comparable to or better than similar studies, confirming its effectiveness. The successful validation of the forcing terms, driving the sediment dynamics, allowed the representation of different processes controlling the sediment transport and their interrelationship. The sediment transport model depicted relatively satisfactorily the seasonal dynamics of the sediment transport patterns, controlled by the intensity of the wave and current activity. This study is among the first to apply CROCO to sediment transport in a coastal domain, integrating realistic wave fields and sediment bed grain size distributions. Modifications to the source code, detailed in supplementary materials, enhance CROCO’s applicability to coastal sediment transport studies. This numerical framework provides a valuable tool for advancing sediment transport and coastal dynamics research, aiding regional marine management and conservation efforts.