On the Assimilation of Multi-Source of Directional Wave Spectra from Sentinel-1A and 1B, and CFOSAT in the Wave Model MFWAM: Toward an Operational Use in CMEMS-MFC
Résumé
The increasing number of directional wave spectra from satellites is a very important opportunity for the improvement of operational wave forecast. This will lead to a better understanding of swell dissipation which is still a top task in wave modeling. This work aims to investigate how the assimilation of different sources of directional wave spectra will impact the analysis and forecast of wave parameters. Two satellites, sentinel-1A and 1B, provide the level 2 SAR wave spectra, which have been qualified for operational use regarding to the calibration/validation phase developed in the last two years. This year the launch of the satellite CFOSAT will ensure a third source directional wave spectra from the real aperture radar SWIM and a significant wave height at nadir look. Synthetic wave data of SWIM and wave spectra from S1A and S1B are assimilated conjointly in the wave model MFWAM for 1 cycle of 13 days during the southern winter season. Two sets of synthetic SWIM data with and without instrumental errors have been tested in the assimilation. The validation of the results with altimeters significant wave heights shows a significant impact in the periods of analysis and forecast. In this study we also investigated the impact of instrumental errors provided by SWIM simulator and the wavelength cut-off on the assimilation results.