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Data

Anonymous User <nospam@ez.no> -
Tuesday 25 April 2006
In the mean wind fields (MWF/WOCE product), when recomputing the module from the zonal and meridional components, the result is not equivalent to the module provided within the product : Why?
They are no wind data (WNF or mean wind fields) from ERS-2 scatterometer after January 2001 : Why?

In the mean wind fields (MWF/WOCE product), when recomputing the module from the zonal and meridional components, the result is not equivalent to the module provided within the product : Why?

The mean(zonal^2+meridional^2) is not equivalent to (mean(zonal)^2+mean(meridional)^2). The same principle applies to the kriging method, the objective interpolation used to estimate the mean wind fields, so components and module are computed separetly. Otherwise, the wind module would be generally underestimated.

They are no wind data (WNF or mean wind fields) from ERS-2 scatterometer after January 2001 : Why?

The wind vectors are retrieved from ERS-2 scatterometer. The failure of some gyroscopes onboard ERS-2 platform caused the satellite to run in a coarse attitude control mode. As a consequence, scatterometer data products are not calibrated anymore and not distributed to users. A re-design of the scatterometer data processor by ESA shall be performed to restore the initial data quality. This reprocessing is not planned yet.