Numerical studies on flow amplification at an isolated shelfbreak bank, with application to Porcupine Bank

A terrain-following coordinate ocean circulation model is used to study different mechanisms of flow amplification at a shelf-edge submarine bank. The work is motivated by repeated hydrographic surveys which revealed strong currents and anomalous density structures at Porcupine Bank, located at the shelf edge west of Ireland. Both steady and periodic forcing are investigated for weak, moderate and strong stratification. The resulting time-mean flows differ significantly in strength and structure and suggest that flow rectification through resonant amplification of diurnal trapped waves is the main process to explain the observed density and current fields.