Alaska Reliability Assessment for Operational Wave Forecasting System in Prince William Sound

To ensure the safety of a variety of marine operations, ocean weather monitoring and prediction in many coastal regions have gained prominence over the last couple of decades. To support ongoing forecasting efforts in Prince William Sound, the site of the worst oil spill disaster in U.S. history, a three-way coupled wave forecasting system is developed. The issue of wave forecast reliability is addressed in the context of the associated uncertainty that confronts the manager of engineering operations or other planners. This issue has generally not been systematically addressed in literature. High-resolution 36-h daily forecasts of significant wave heights (SWHs) are compared with measurements from buoys and satellites for about 1 year. The results show that 70% of the peak SWHs (in the range 58 m) were predicted with an accuracy of 15% or less for a forecast lead time of 9 h. The errors are larger for smaller SWHs. Correlation coefficients (R2) and indices of agreement (D) between predicted and measured SWHs were reasonable and generally more than 0.78 for all lead times. On average, our analysis showed 70% or greater likelihood of the prediction falling within a tolerance of (1 RMSE) for all lead times. Barring changes in model physics, resolution, etc., similar acceptance levels could be expected from comparable systems. 2010 ASCE.

Reliability Assessment for Operational Wave Forecasting System in Prince William Sound, Alaska