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arXiv · 2510.06484

Skill of Long-Range Forecasts of Ocean Wave Spectra from the Navy ESPC Version 2 System

W. E. Rogers·M. A. Janiga
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Abstract

We report the outcome of evaluations of the skill of long-range forecasts from the ocean wave model component of the Navy's global coupled modeling system. Specifically, the model output is taken from a single member of the ensemble system, and we evaluate the skill of predicting seven model "wave height" parameters, computed from: energy in four frequency bands, energy in all bands combined, swell energy, and wind sea energy. The model is evaluated using two methods of "ground truth". The first is a new instrument for measuring wave spectra from space, Surface Waves Investigation and Monitoring (SWIM). The second is analyses from the same model. We propose a new method of band-wise bias correction of the observational dataset, using in situ wave observations, with the numerical wave model used as an intermediary.

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W. E. Rogers, M. A. Janiga. 2025-10-07. Skill of Long-Range Forecasts of Ocean Wave Spectra from the Navy ESPC Version 2 System. https://arxiv.org/abs/2510.06484

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