Impact of offshore wind farms on regional-scale sediment transport pathways in the North Sea

The rapid expansion of offshore wind farms (OWFs) in the North Sea necessitates a better understanding of its impacts on ocean dynamics, regional-scale sediment transport, and erosion and deposition patterns which may consequently influence future states of coastal morphology. Using 3-dimensional hydro-morphodynamic coupled numerical modelling which integrates parameterizations of OWF-effects in both atmosphere and ocean, we analysed how regional-scale sediment transport pathways as well as sediment exchange between the open North Sea and the Wadden Sea are affected by OWFs. We compared the simulation results from different OWF configurations representing present-day (operating), potential future (operating, in-construction and planned) scenarios. In particular, we investigated the OWF impact on the frontal systems, residual transport, accumulation of fine-grained sediment in the mud depocenters and sediment flux between the open North Sea and tidal basins in the Wadden Sea. Our results highlight the potential of OWFs in reshaping regional-scale sediment transport patterns, with implications for ecosystem functioning, marine spatial planning and coastal protection strategy. The outcomes may be used to align sustainable offshore wind energy development and coastal protection in the North Sea and at its coasts.