The influence of coastal morphology on the wave climate and wave energy resource of the west Irish coast

Abstract

Abstract —The wave climate and wave resource for two sites on the western coast of Ireland which possess steep bathymetric gradients and complex shorelines are investigated. One is situated in the southern part of Achill Island on the Co. Mayo coastline, whereas the second is centered at Killard point on the Co. Clare coast. The wave climate is estimated using the third generation spectral wave model WAVEWATCH III, forced with directional wave spectral data and 10m winds obtained from the European Centre for Medium Range Weather Forecast (ECMWF) archive. The local area models are validated with wave buoy and Acoustic Doppler Current Profiler (ADCP) data for intermediate to shallow depths (50m or less) obtained from the ESB’s WestWave project. Our results show that for an accurate representation of the directionality in the nearshore, in particular for steep bathymetric slopes found at the cliffs and exposed rocky shores of the Irish coastline, reflection needs to be accounted for. It has been found that reflection affects mainly the directional spread of the resource and to a lesser degree the significant wave height.