Simulating storm waves in the Irish Sea

• Published in: Proceedings of the Institution of Civil Engineers - Maritime Engineering
• Main Authors: Elliott, A. J., Neill, S. P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Thomas Telford Ltd. 2007
• Subjects: Ocean Engineering; North Atlantic
• Online Access: http://dx.doi.org/10.1680/maen.2007.160.2.57; https://www.icevirtuallibrary.com/doi/pdf/10.1680/maen.2007.160.2.57

A third-generation wave model (PRO-WAM) has been applied to the North Atlantic and to a nested Irish Sea domain. The accuracy of the model was assessed by hindcasting storms that occurred during 1–15 January 2005 when the wind speed reached 25 m/s and wave heights of 12 m were recorded off the west coast of Ireland. The agreement between the model and the data from five offshore wave buoys was excellent at four of the five locations. An analysis of the relationship between wave height and period at the fifth site suggests that the buoy had malfunctioned. Two rapid-calculation methods for estimating a wave field were evaluated. The first method involved computing the time-invariant waves for a range of fixed wind speeds and directions then creating a look-up table for each grid cell. The second method used formulae derived from the JONSWAP spectrum. Of the two methods, the look-up table technique provided the better results. The PRO-WAM model is run operationally each day and the results stored in a data archive. The output is suitable for specifying the offshore boundary conditions for near-shore, high-resolution wave models, which could be interfaced to tidal and sediment transport models.