NOAA-17 HIRS Callibration Correction , 24 September 2002 - Issued: 25 September 2002; 0530 UTC

NOAA-17 HIRS Calibration Correction

Date/Time(UTC) Message Issued:
25 September 2002 0530 UTC

Satellite(s) Involved:

Instrument(s) Involved:

Product(s) Involved/Affected:
Level 1B/1B* files

Date/Time(UTC) of Initial Implementation:
24 September 2002 2152 UTC

Details/Specifics of Change:
One HIRS level 1B file per day has been erroneously exhibiting symptoms of
moonglint where the insufficient data to calibrate quality indicator bit was
set. Analysis determined that this problem occurred following the update of
the HIRS 24-Hour Calibration File. If the next orbit processed could not
retrieve a 24-hour average it would use mean values from the calibration
input dataset (CPIDS) and an offset to validate space counts. The mean
contained a pre-launch value that triggered a moonglint like phenomenon. The
mean value was updated in CPIDS to alleviate the false moon glint

The NOAA-17 CPIDS update was installed into operations at 5:52 pm local
time. The first orbits to be processed after the change are

Contact Person(s) Name/Email/Phone Number for Questions:
Emily D. Harrod/ ext 117

Web site(s) that contain other relevant information (where applicable): - SOCC morning reports - History of level 1B
notices - All user notices