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Different calibration methods (temperature/radiance tables) have been used for the Meteosat satellite series, Meteosat First Generation (MFG) and Meteosat Second Generation (MSG) to convert the radiances into brightness temperatures.
Meteosat IR/WV Channel Calibration Methods
Meteosat VIS Channel Calibration is not provided for real-time dissemination, but estimated off-line.
For the Meteosat-6 Rapid Scan Service (RSS) a Satellite Cross Calibration was used to correct the image anomaly, with the result that the images were radiometrically stable. From 1 October 2002 the RSS images were disseminated with constant IR and WV calibration coefficients between gain changes. The following calibration coefficients are being updated, again on a daily basis, from 29 September 2005 onward. *Important notes: - Meteosat-2 Calibration Coefficients are available for the period February 1982 until August 1988.- Calibration Coefficients generated before 22 February 1982 are not documented well enough and therefore they are not published.- The spacecounts until June 1986 were not recorded, however, it is assumed that they are the same as those that were delivered from July 1986 onwards. The coefficients listed in the calibration pages are valid from the indicated slot (time) onwards.Historical Calibration Information and Spacecraft-Dependent Variables The spectral response data have been provided by the spacecraft manufacturer. Due to a pre-launch problem the spectral responses for Meteosat-5 and -6 might be non-optimal, and investigations have shown that using the Meteosat-7 spectral response data for these two spacecraft gives a more consistent result. Normalised Spectral Response data Temperature to radiance tables for Meteosat-5, -6 and -7 The radiance-to-temperature relation tables given below allow the conversion from temperature to radiance, and vice versa, for the WV and IR channels of Meteosat-5, -6 and -7. |
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