Storm surge computations for the Irish Sea using a three-dimensional numerical model including wave–current interaction

A brief overview of the mathematical development (with references to the literature for detail) of a high-resolution (of order 1 km grid) three-dimensional model of the wind-driven flow in the eastern Irish Sea, including wave–current interaction is presented. The model is applied to the computation of the storm surge of November 1977, and the importance of local wind fields compared to far-field winds upon the surge in the eastern Irish Sea is examined. The significant improvement in surge elevations at Liverpool produced by using a high-resolution grid is clearly demonstrated by comparing results with earlier coarse grid models. Further improvement obtained by including wave–current interaction effects is also demonstrated. Differences between surface and near-bed currents and the high degree of spatial variability in bottom currents during major storms in the eastern Irish Sea is also considered.