A new satellite to measure winds and waves

Image of the Month - October 2018

CFOSAT artist's view (Credits Cnes/ill. Oliver Sattler)
CFOSAT artist's view (Credits Cnes/ill. Oliver Sattler)
Wave spectrum (combined 6,8 and 10°) prefiguring SWIM results. Azimuthal cut-off ~70 m (SAR ~ 200m) (Credits Meteo France)


Significant wave heights and wind speed modulus are among the measurements done by classical altimeter. Those two oceanic parameters have a very high importance in a number of practical applications, though - marine and also coastal security, infrastucture building, ocean/atmosphere interactions, weather forecasting... To address these questions the French and Chinese Space Agencies, Cnes and CNSA, have build a new satellite, CFOSAT, which is planned to be launched at the end of October 2018. CFOSAT will carry two radar instruments: a wave scatterometer supplied by Cnes, SWIM (Surface Waves Investigation and Monitoring),  and a wind-field scatterometer supplied by CNSA, SCAT (wind SCATterometer). This is the first time that two such measurements will be done at the same time; it is also the first scientific France - China cooperation. 

SWIM is a entirely new instrument with unheard-of capabilities. It will scan the ocean with its six rotating beams, at angles from 0° to 10° to measure the wave spectrum in two dimensions, providing access to wave direction, wavelength and SWH per sea state. 

These data will enable more accurate ocean weather  forecasts, as well as a better knowledge of winds, waves and their interactions. CFOSAT will also help climatologists to learn more about exchanges between the oceans and atmosphere, since the waves are playing an important part in those exchanges (see Image of the Month, Aug. 2002: Gas in the water), exchanges which play a key role in climate.

In addition to the operational series (Jasons, Sentinel-3s), several new satellites, with brand-new altimetry-related capabilities are either about to be launched (CFOSAT), are under construction and will be launched (Swot), or are under studies for the future (Skim). These new concepts should reinforce operationally  the conventional altimeters for a better characterization of the ocean.

See also:

Other websites on this topic:

  • CFOSat on Cnes projects library