NOAA Office of Satellite and Product Operations

GOES Calibration

Most recent spectrual response functions available for each instrument:

How are the detectors behaving on the Imager and Sounder? Let's take a look at two representative samples

  1. GOES-8 Imager Channel 4 Detector 1(plot)
    Ever since the summer of 1994, we have been monitoring responsivities of each imager IR detector. With the patch temperature set at 101°C degrees, the slope (inverse of the responsivity) trended at about -0.23. In August, 1994 the patch temperature was lowered to 94°C degrees. At a colder temperature, the absolute value of the slope decreases as seen in the plot. In April 1995, SOCC introduced a scan mirror emissivity correction to the calibration algorithm, and a change in slope was observed. In the summer months of 1995-1998, the patch was maintained at 101°C degrees. The slope is stable near -0.22. During all other months of the year the patch is controlled at 94°C degrees, operating with a stable slope near -0.18.
  2. GOES-8 Sounder Channel 8 Detector 1(plot)
    Monitoring efforts for the GOES-8 Sounder started in the summer of 1994. Initially the detector patch was controlled at 101°C degrees. In August 1994, the patch temperature was lowered to 94°C degrees, and has remained at that temperature since. In October 1994, the first sounder decontamination was done for a 48-hour period to drive off contaminants from the cooler housing window. Starting in December 1994, we began a weekly decontamination effort which runs for a 24-hour period each week to slow the contamination process. This weekly process usually runs until the end of April when the cooler housing temperature gets hot enough to drive off contaminents without additional heating sources. The large rise in slope centered around Quarter 3 (Q3) is associated with the fluctuation in patch temperature during the summer months.


Latest Revision: August 2014.