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ABSTRACTA methodology for quantitative, directional validation of a long-term wave model hindcast is described and applied.Buoy observations are used as ground truth and the method does not require the application of a parametric model or data-adaptive method to the observations. Four frequency ranges, relative to the peak frequency, are considered. The validation of the hindcast does not suggest any systematic bias in predictions of directional spreading at or above the spectral peak. Idealized simulations are presented to aid in the interpretation of results. ABSTRACT A methodology for quantitative, directional validation of a long-term wave model hindcast is described and applied. Buoy observations are used as ground truth and the method does not require the application of a parametric model or data-adaptive method to the observations. Four frequency ranges, relative to the peak frequency, are considered. The validation of the hindcast does not suggest any systematic bias in predictions of directional spreading at or above the spectral peak. Idealized simulations are presented to aid in the interpretation of results.
1.Introduction turning winds is a concern (e.g., Young et al. 1987). The ability of third-generation models to accurately predict a. Back ground the width of the directional distribution is poorly un-1) IMPORTANCE/RELEVANCE derstood. Indeed, as is described in a companion manuscript (Rogers and Wang 2006, hereafter RW), evaluaPrincipal wave direction, quantified as a mean or tions in the literature show very little consensus. peak value, is of obvious importance to wave prediction. Directional distribution about the mean or peak direction is also very important for wave modeling. It b. Model description can have a large impact on the prediction of swells,The so-called third-generation (3G) of spectral wave since it determines how far and wide the swells will models calculate wave spectra without a priori assumpdisperse. Nonlinear interactions computed by a wave tions regarding spectral shape. For this investigation, model are sensitive to the direction...
