Statistical modeling of the space–time relation between wind and significant wave height

• Published in: Advances in Statistical Climatology, Meteorology and Oceanography
• Main Authors: Obakrim, Said, Ailliot, Pierre, Monbet, Valerie, Raillard, Nicolas
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2023
• Subjects: North Atlantic
• Online Access: https://archimer.ifremer.fr/doc/00841/95277/103036.pdf; https://doi.org/10.5194/ascmo-9-67-2023; https://archimer.ifremer.fr/doc/00841/95277/

Many marine activities, such as designing ocean structures and planning marine operations, require the characterization of sea-state climate. This study investigates the statistical relationship between wind and sea states, considering its spatiotemporal behavior. A transfer function is established between wind fields over the North Atlantic (predictors) and the significant wave height (predictand) at three locations: southwest of the French coast (Gironde), the English Channel, and the Gulf of Maine. The developed method considers both wind seas and swells by including local and global predictors. Using a fully data-driven approach, the global predictors' spatiotemporal structure is defined to account for the non-local and non-instantaneous relationship between wind and waves. Weather types are constructed using a regression-guided clustering method, and the resulting clusters correspond to different wave systems (swells and wind seas). Then, in each weather type, a penalized linear regression model is fitted between the predictor and the predictand. The validation analysis proves the models skill in predicting the significant wave height, with a root mean square error of approximately 0.3 m in the three considered locations. Additionally, the study discusses the physical insights underlying the proposed method.