Hydrodynamic Processes Controlling Sand Bank Mobility and Long-Term Base Stability: A Case Study of Arklow Bank

Offshore sand banks are an important resource for coastal protection, marine aggregates, and benthic habitats the site of many offshore wind farms. Consequently, a comprehensive understanding baseline processes controlling bank morphodynamics is imperative. This knowledge will aid development long-term robust spatial plan help address environmental instability arising from anthropogenic activities. study uses validated, dynamically coupled, two-dimensional hydrodynamic sediment transport model to investigate highly mobile upper layer Arklow Bank, while maintaining overall base stability. The results reveal flood ebb tidal current dominance on west east side bank, respectively, ultimately generating large anticlockwise residual eddy encompassing entire bank. flow distributes along full length positioning multiple off-bank eddies edge this cell shown influence east–west fluctuations slopes act as control These facilitate type movement when outer flows adjacent eddies, located both sides in general uniform direction. Whereas they inhibit either converging directions towards itself. also out local system. Within Bank’s morphological cell, eight morphodynamically hydrodynamically unique sections or ‘sub-cells’ identified, whereby complex morphodynamic–hydrodynamic feedback loop present. fluctuation driven by migratory on-bank stationary transient clockwise ‘narrow’ cross-flow zones. Together, these drive slope mobility but maintain novel applicable bedforms tidally dominated continental shelf seas outside Irish Sea.