Abstract's details
CFOSAT: New wind and wave observations from the nadir and near-nadir SWIM Ku-Band instrument
CoAuthors
Event: 2019 Ocean Surface Topography Science Team Meeting
Session: CFOSAT
Presentation type: Type Oral
Contribution: not provided
Abstract:
CFOSAT is a new oceanographic satellite mission which has been successfully launched on October 29th 2018. It was jointly developed by the French and Chinese space agencies (CNES, CNSA, NSOAS). Its payload is composed of two Ku-Band radar instruments, namely SWIM (“Surface Waves Investigation and Monitoring”), which operates in a near-nadir geometry (0-10° from nadir) and scans in azimuth over 360°, and CSCAT which is a fan-beam rotating wind-scatterometer operating at larger incidences (20-55°). SWIM was designed to provide new information on the directional spectra of ocean waves along with the more conventional observations of wind and significant wave height obtained from the nadir altimetric signal.
During this conference, we will focus on the SWIM results obtained over several months of observations. We will first recall the data processing principles of the SWIM data and the main products. Then, based on the common analysis of the expert research group organized for the CAL/VAL, the performance of the SWIM instrument will be presented, and the main results from the nadir beam and off-nadir beams will be discussed. In particular we will present the capacity of SWIM to provide both the significant wave height and the detailed properties of the waves such as the dominant wavelength and direction for several components of the wave field. This assessment relies on comparisons between SWIM data, satellite altimeter products, wave forecast model products (WAM from ECMWF and Meteo-France, WW3), in situ data, and other satellite data (altimeters, SAR).
We will also illustrate from case studies the interest of the spectral information on ocean waves to study wave growth and evolution, wave/current interactions, wave behaviour under sea ice and the importance of open ocean forcing conditions for coastal studies.
First tests of assimilation of spectral data will also be illustrated. The results show a significant impact on integrated wave parameters (SWH and mean period) in the analysis and forecast periods. This opens promising applications for operational wave forecasting.
During this conference, we will focus on the SWIM results obtained over several months of observations. We will first recall the data processing principles of the SWIM data and the main products. Then, based on the common analysis of the expert research group organized for the CAL/VAL, the performance of the SWIM instrument will be presented, and the main results from the nadir beam and off-nadir beams will be discussed. In particular we will present the capacity of SWIM to provide both the significant wave height and the detailed properties of the waves such as the dominant wavelength and direction for several components of the wave field. This assessment relies on comparisons between SWIM data, satellite altimeter products, wave forecast model products (WAM from ECMWF and Meteo-France, WW3), in situ data, and other satellite data (altimeters, SAR).
We will also illustrate from case studies the interest of the spectral information on ocean waves to study wave growth and evolution, wave/current interactions, wave behaviour under sea ice and the importance of open ocean forcing conditions for coastal studies.
First tests of assimilation of spectral data will also be illustrated. The results show a significant impact on integrated wave parameters (SWH and mean period) in the analysis and forecast periods. This opens promising applications for operational wave forecasting.