The entire 16-year surface turbulent fluxes estimated from satellite observations are reprocessed. The main improvements with respected to previous products are related to the assessment of the surface winds retrieved from ERS-1, ERS-2, and QuikSCAT scatterometers, and to the use of the new NOAA sea surface temperature estimates. The latter are daily-averaged and 0.25° in longitude and latitude over the global ocean. The new turbulent fluxes are estimated using Fairall et al (2003) bulk algorithm. The resulting weekly and monthly 10-m wind speed (W), 10-m specific air humidity (Qa), 10-m air temperature (Ta), wind stress (tau), latent heat flux (LHF), and sensible heat (SHF) flux fields are first validated against weekly and monthly averaged in-situ data. At global scale, the spatial and temporal satellite flux patterns are compared to those from HOAPS3, OAFLUX, ECMWF, and ERA40 fluxes.
This new product available at CERSAT consists of weekly and monthly gridded fields of CO2 exchange coefficients derived from scatterometer ocean surface winds and sea surface temperature, using several relationships relating these parameters together. Fields have been produced separately from each available scatterometer (ERS-1, ERS-2 and QuikSCAT) providing a cumulated time series of more than 15 years. The data are available on ftp and are regularly updated. This work is a joint collaboration between the CERSAT and the LOCEAN.
Extending the dataset set up with ERS-1, ERS-2 and NSCAT series, CERSAT provides the scientific community with easy-to-use synoptic gridded fields of wind-related parameters (speed and stress vectors), estimated from observations by NASA scatterometer SeaWinds onboard QuikSCAT. They are provided with three time resolutions - daily, weekly and monthly averages - on a global 0.5°x0.5° resolution grid, since July 1999. The data are available in netCDF format and quicklook pictures are also provided.
The full package gathering all data collected along the WOCE experiment (in-situ, satellite, models,...) is now available on a double DVD. The data are stored as homogeneous netCDF files. Search and visualization tools are also included within the DVDs. As a contribution to this dataset, CERSAT provides global satellite mean wind fields, weekly and monthly averaged, covering the 1991-2002 period and using measurements by ERS-1, ERS-2, ADEOS/NSCAT and QuikSCAT.
The DVD was first distributed at WOCE final conference, hold in San Antonio (Texas) from 18th to 22nd November. It will be soon available at CERSAT.
Nevertheless, the satellite mean wind fields featured within the DVD are already available on CERSAT anonymous ftp server (ftp.ifremer.fr, folder : ifremer/cersat/products/gridded/mwf-*) or on our web site ("data" topic).
Waves are being measured over the whole surface of the ocean by ESA satellite ENVISAT. Before being assimilated operationaly in forecasting models, the ENVISAT/ASAR wave data have to be fully calibrated and validated. In order to make this task easier, CERSAT is providing users with colocated datasets of ASAR (onboard ENVISAT) cross-spectra and wave spectra with in-situ measurements (wind, waves, sst) from various buoy networks. Envisat ASAR Wave mode products are also colocated with WAM data from the ECMWF model.