Articles | Volume 12, issue 4
Research article
05 Jul 2016
Research article |  | 05 Jul 2016

Modelling wave–current interactions off the east coast of Scotland

Alessandro D. Sabatino, Chris McCaig, Rory B. O'Hara Murray, and Michael R. Heath

Abstract. Densely populated coastal areas of the North Sea are particularly vulnerable to severe wave conditions, which overtop or damage sea defences leading to dangerous flooding. Around the shallow southern North Sea, where the coastal margin is lying low and population density is high, oceanographic modelling has helped to develop forecasting systems to predict flood risk. However, coastal areas of the deeper northern North Sea are also subject to regular storm damage, but there has been little or no effort to develop coastal wave models for these waters. Here, we present a high spatial resolution model of northeast Scottish coastal waters, simulating waves and the effect of tidal currents on wave propagation, driven by global ocean tides, far-field wave conditions, and local air pressure and wind stress. We show that the wave–current interactions and wave–wave interactions are particularly important for simulating the wave conditions close to the coast at various locations. The model can simulate the extreme conditions experienced when high (spring) tides are combined with sea-level surges and large Atlantic swell. Such a combination of extremes represents a high risk for damaging conditions along the Scottish coast.

Short summary
The present research describes the effect of wave–current interactions and wave–wave interactions during severe storms on the east coast of Scotland. In this area, results show that the currents contribute substantially to the modification of wave properties in the shallow coastal areas, while the wave–wave interactions are more important offshore.