On the update of swell dependency for SAR mode altimetry of Sentinel-3

Lotfi Aouf (Division Marine et Océanographie Météo-France, France)


Alice Dalphinet (Meteo-France, France)

Event: 2018 Ocean Surface Topography Science Team Meeting

Session: Application development for Operations

Presentation type: Type Poster

For the future altimetry missions it is important to assess the impact of long swell on the SAR mode retrieval for significant wave height (SWH). In our previous work the use of Sentinel-1 wave spectra has pointed out the strong correlation between long swell ocean regions and the increase of bias of SWH induced by the assimilation of Sentinel-3 (S3) SAR mode wave data.
Since December 2017 an upgraded level 2 processing has been implemented by EUMETSAT and ESA, which induced a significant improvement on retrieved SWH from the SAR mode of S3A. This paper aims to investigate whether the upgraded processing affects the dependency between swell and the SAR mode retrieval. A long period of more than 6 months including southern winter has been considered for this study. The assimilation of S3A in the wave model MFWAM has been developed for the global scale. the results are validated with independent altimeters SWH and buoys wave data. A comparison with combined assimilation of altimeters and SAR wave spectra from Sentinel-1 has been also performed. Statistical analysis of SWH is implemented depending on ocean region dominated by swell wave systems with wavelength ranged from 300 to 400 meters, such as south-west of Australia and the Agulhas ocean regions.
Since the launch of S3B in April 2018, additional comparison between LRM and SAR mode of S3 is examined during the tandem phase of the two satellites (S3A and S3B).
Further discussions and conclusions will be commented in the final presentation.

Poster show times:

Room Start Date End Date
Foyer, Salao Nobre & tent Thu, Sep 27 2018,18:00 Thu, Sep 27 2018,20:00
Foyer, Salao Nobre & tent Fri, Sep 28 2018,14:00 Fri, Sep 28 2018,15:00
Lotfi Aouf
Division Marine et Océanographie Météo-France