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Message Issued: March 26, 2009 1715 UTC Satellites Impacted: GOES-13Products Impacted: GOES-13 Imager Data and Products using the 13.3 micron (band 6) channel
Date/Time of Initial Impact: March 26, 2009 1934 UTC ----------------------------------------- Details:The Cooperative Institute of Meteorological Satellite Studies (CIMSS) at the University of Wisconsin-Madison reported a cold bias of -2.4 K for GOES-13 Imager Band 6 (13.3 um) in March 2007, and recommended shifting the spectral response function (SRF) by -4.7 cm-1 . ITT reanalyzed the pre-flight data and revised the SRF in October 2007, which effectively shifts the SRF by -1.2 cm-1 . NESDIS/OSO implemented the ITT-revised SRF in July 2008.
NESDIS/STAR confirmed that the bias is caused by SRF error and recommended an additional shift of -2.1 cm-1 to the ITT-revised SRF. Plus, more comparisons were made to both AIRS and IASI data. NESDIS/OSO will implement the NESDIS-revised SRF on March 26, 2009 at 1934 UTC, with revised central wavenumber and band correction coefficients.
The updated shifted SRF greatly reduces the overall bias of the Imager 13.3 um (band 6). This in turn, improves the accuracy of products derived from this band, such as cloud-top heights and the height assignment of atmospheric motion vectors. Users will need to adjust their conversion from radiance to brightness temperature for this band.
Users can obtain details on the updated SRF at: http://www.oso.noaa.gov/goes/goes-calibration/goes-imager-srfs.htm -------------------------------------- Contact Information: Brian Hughes Satellite Services Division NOAA/NESDIS/OSDPD 301-763-8051 x106 brian.hughes@xxxxxxxxSee http://www.ssd.noaa.gov/PS/SATS/messages.html for this and other satellite related messages.
See http://www.ssd.noaa.gov for full GOES scanning schedules.
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