|
In fluid dynamics, wind wave modeling describes the effort to depict the sea state and predict the evolution of the energy of wind waves using numerical techniques. These simulations consider atmospheric wind forcing, nonlinear wave interactions, and frictional dissipation, and they output statistics describing wave heights, periods, and propagation directions for regional seas or global oceans. Such wave hindcasts and wave forecasts are extremely important for commercial interests on the high seas.〔 〕 For example, the shipping industry requires guidance for operational planning and tactical seakeeping purposes.〔 For the specific case of predicting wind wave statistics on the ocean, the term ocean surface wave model is used. Other applications, in particular coastal engineering, have led to the developments of wind wave models specifically designed for coastal applications. ==Historical overview== Early forecasts of the sea state were created manually based upon empirical relationships between the present state of the sea, the expected wind conditions, the fetch/duration, and the direction of the wave propagation.〔Wittmann, Paul and Mike Clancy, ("Thirty Years of Operational Ocean Wave Forecasting at Fleet Numerical Meteorology and Oceanography Center" ), ''Symposium on the 50th Anniversary of Operational Numerical Weather Prediction'', 14–17 June 2004, University of Maryland〕 Alternatively, the swell part of the state has been forecasted as early as 1920 using remote observations.〔Robert Montagne, The swell forecasting service in Morocco (In French), 1922, Annales Hydrographiques, pp. 157-186. This paper describes the use of the method published by Gain in the same journal (1918) which combines a classification of North Atlantic Storms with the use of observations in Azores and Portugal to forecast the swells in Morocco.〕 During the 1950s and 1960s, much of the theoretical groundwork necessary for numerical descriptions of wave evolution was laid. For forecasting purposes, it was realized that the random nature of the sea state was best described by a spectral decomposition in which the energy of the waves was attributed to as many wave trains as necessary, each with a specific direction and period. This approach allowed to make combined forecasts of wind seas and swells. The first numerical model based on the spectral decomposition of the sea state was operated in 1956 by the French Weather Service, and focused on the North Atlantic.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Wind wave model」の詳細全文を読む スポンサード リンク
|