Ifremer Wind and Wave Operation Center (IWWOC)

The Ifremer Wind and Wave Operation Center (IWWOC) is a project within CERSAT, conceived as a delayed mode data production and distribution center for advanced wind and wave products generated from the SWIM and SCAT instruments onboard the Chinese-French CFOSAT mission. It is co-funded by CNES and Ifremer.


CFOSAT (the China France Oceanography Satellite) is a joint mission, launched on the 29th October 2018, from the Chinese and French Space Agencies (CNSA, NSOAS, CNES), devoted to the observation of ocean surface wind and waves and related science and applications. This innovative mission embeds two Ku-Band active instruments: SWIM, dedicated to the measurement of directional of ocean surface waves, and SCAT, dedicated to the measurement of ocean surface wind vectors. By providing wind and wave vectors at the same time and at a global scale, CFOSAT has already demonstrated its potential for contributing to important fields of research, especially in the following topics:  atmosphere/ocean exchanges, ocean wave physics, sea-ice monitoring,  atmospheric, wave and oceanic modeling or forecast, and climate monitoring of wind and wave fields. Thanks to the new types of observations (directional wave spectra), it is also a key element to prepare future oceanographic satellite missions such as those devoted to surface current measurements and new generation of altimetry concept.

The French CFOSAT Ground Segment is composed of two main mission centers:

  • the CWWIC operated by CNES in Toulouse (France) for near-real time processing, up to the Level2 products.
  • the Ifremer Wind and Wave Operation Center (IWWOC operated by Ifremer in Brest (France) for differed-time data processing, distribution and archiving (alternative L2, L3 and L4).

The main objective of the IWWOC is to develop and deliver:

  • swath (level 2) wind and wave products in delayed-mode (> 24h)
  • multi-sensor wave and wind fields combining both instruments and later other sources of measurements (such as Sentinel-1 SAR data)
  • intercomparison products (colocations with buoys and models, cross-overs between satellite missions,...) to support the development of the algorithms and the validation of the IWWOC products
  • continuous quality assessment and monitoring of the sensor geophysical performances
  • science applications


The first batch of IWWOC products includes:

  • An alternative SWIM L2 processing, called L2Sproviding along-track directional wave spectra measures, as well as the  integrated parameters of the associated wave systems (wave length,  significant wave height, direction), over the global ocean
  • sea ice roughness maps generated daily from SCAT scatterometer over Arctic and Antarctic poles allowing discrimination between sea ice and water but also first-year and multi-year ice
  • A synergy product between SWIM and SCAT colocating the measurements of both instruments over SCAT geometry, with multiple auxiliary fields. This research is especially intended to explore the combination of both instruments. 
  • systematic colocations between CWWIC SWIM L2 and IWWOC SWIM L2S wave measurements and wave spectra estimated from WaveWatch3 model

The full description of each product is provided in the dedicated IWWOC product catalogue and on ODATIS web site.

The IWWOC products can be accessed through HTTP or FTP at, respectively:

The data access is free and open but in order to be informed about changes and to help us keep track of data usage, we encourage users to register at: https://forms.ifremer.fr/lops-siam/access-to-iwwoc-cfosat-data/.