Modelling waves at Orkney coastal locations

We have explored the possibility of deriving coastal wave conditions from the archived data of operational large scale modelling. Starting from this data, a high resolution nested grid has been used to derive wave results at two locations where buoy data is available. The comparison suggests that the used solution can be used to provide long term statistics or reliable forecasts at desired coastal locations. The accuracy and the limitations of the approach have been explored by analysing the sensitivity of the results to the frequency of the archived information and of the wave model spectral shape. The problems connected to inputting the correct spectral shapes are discussed.

► Integral parameters are a poor input to local modelling leading to Hs underestimate.
► A similar problem exists with interpolated, in space and time, 2D spectra.
► ECMWF archived global model data are a suitable input for long-term local modelling.