Analysis of the Uncertainty in the Prediction of Overtopping in Coastal Numerical Models

The purpose of this study is to examine the variability of the overtopping parameters in coastal numerical models due to the boundary condition reconstructed from a spectra. Firstly, the numerical model which is based on the Non-Linear Shallow Water Equations is validated against laboratory wave flume tests. An energy spectrum is also obtained from each of these experiments. These spectra are then used within a Monte Carlo approach to generate random wave series for each test, by the introduction of random phasing. This introduces variability in the prediction of the overtopping parameters as an infinite number of time series can be generated for each wave condition. It is observed that in some of these conditions this produces variation in the region of a factor of 200 in the prediction of overtopping parameters.