NUMBER 162

DATE: 01/03/97

Sector Processing Center (SPC):

During November, NOAA, JMA, AES and CSU processed greater than 91% of A data into B1/B2 data.

Normal operations for November were reported by NOAA, AES and JMA. No report was received from EUM.

CSU reported that NOAA was still testing the GOES-9 imager scan motor until 2 November causing cancellation of images at 0600, 0900 and 1200 UTC for the first two days. CSU is supplying the AC data for GOES-8 while AES revises their format.

NOAA reported requesting supplemental funding for the new year to provide the 6.7 micron radiances from HIRS to normalize the corresponding channels on GMS-5, GOES-8 and GOES-9.

Satellite Calibration Center (SCC):

No report was received; however, BC data for September 96 for all satellites were shipped to the GPC.

Global Processing Center (GPC):

The GPC continued to receive B2 data, BC data and correlative data in a routine manner.

Production of NOAA-14 (preliminary) B3 is current. Production of final B3 will require normalizing the calibration to the standard, NOAA-9.

Production of NOAA-12 (preliminary) B3 data is current. Final B3 data have been delivered through December 95.

Production of GOES-7 (preliminary) B3 data is complete. Final B3 data have been delivered through June 94.

GOES-8 B2 data have been received through November 96. More recent deliveries include the calibration block, but the status of this information for the older datasets is not clear. The formatting software has not been written yet.

GOES-9 B2 data for January 96 have been delivered in final form. Now that the format has been determined, deliveries of the backlog will commence. The formatting software has not been written yet.

Production of METEOSAT-3 (preliminary) B3 data is completed through January 95. The special CD-ROM datasets sent by ESA for February through April 95 have not been processed yet. Final B3 data have been delivered through June 94.

Production of METEOSAT-5 (preliminary) B3 data is now current, but only data through April 96 have been received. Final B3 data have been delivered through June 94.

GMS-5 B2 data deliveries are current, but formatting software has not been written yet. Production of GMS-4 (preliminary) B3 data is completed through May 95. Final B3 data have been delivered through June 94.

Final INSAT-1 B3 has been produced for the period April 88 through March 89.

TOVS correlative data processing has been completed through September 96.

Production of the ice/snow correlative dataset is complete through 94. The old source of sea ice data (actually now directly the Navy) has begun producing data again. Also, another sea ice dataset has been released. All of these datasets are being compared to determine which should be used in ISCCP production. An error has been discovered in the new sea ice data used to produce the cloud products for 92 and 93: although a procedure was developed to remove spurious sea ice reports along coastlines, this procedure was not entirely successful. There is still some contamination occasionally. This does not affect the cloud detection and analysis, however, since the algorithm procedure in near-coastal regions is already more conservative than it is over sea ice. The snow/ice fraction reported in the D1/D2 datasets is occasionally incorrect.

DX/D1/D2 processing continues to be slowed by work to upgrade the computer operating system. DX/D1/D2 for September and October 93 has been processed. However, no deliveries beyond January 93 have occurred because of the difficulties with the navigation and visible radiance calibration for METEOSAT-3 (operating as GOES-EAST). The quality checking process detected all of the images that were incorrectly navigated and flagged them so that they were discarded in the cloud analysis; however, too many images were lost in February, April and August 93. There were three different problems: cases where the header reported incorrect (rapidly switching) sub-satellite longitudes, cases where the reported sub-satellite longitudes were correct, but the images were incorrectly projected assuming another value, and cases where the scanlines were truncated improperly. The first two problems have been fixed and the third problem appears fixable. The visible calibration problem appears to be related to difficulties in finding clear ocean scenes for the normalization of the data for April 93; this problem appears to have recurred in October 93 as well. Deliveries of the 93 D-data have been held up while a new trend is investigated. As part of the cloud processing, there is a calibration consistency check performed. In 92, only two satellites in two months failed this check and the calibration was revised slightly. In the first half of 93, the frequency increased to about one satellite every month, sometimes involving the visible and sometimes the infrared calibration. In the second half of 93, all satellites in every month have failed this test for the visible calibration, apparently requiring unusually large calibration corrections in some cases. This has greatly slowed production because the calibration correction requires processing each geostationary satellite twice. This sudden increase in frequency suggests that something has gone wrong with the normalization or the processing and that the correction procedure may not be reliable. No data for 93 will be delivered until this problem is understood and corrected.

There were no additions to the ISCCP Web page last month. The ISCCP World Wide Web Home Page can be accessed at URL

ISCCP Central Archive (ICA):

The ICA continued to receive B1 data from NOA, AES, ESA, CSU and JMA and B3 and C data from the GPC in a routine manner. A new catalog of ISCCP data products was issued in June.

The health of GOES-8, GOES-9, GMS-5, METEOSAT-5, NOAA-12 and NOAA-14 remained good.

Stage B3: July 83 - June 94 (11.0 years)

Stage CD: July 83 - December 94 (11.5 years)

Stage C1: July 83 - June 91 ( 8.0 years)

Stage C2: July 83 - June 91 ( 8.0 years)

Stage D1: January 86 - December 86, January 90 - December 92 ( 4.0 years)

Stage D2: January 86 - December 86, January 90 - December 92 ( 4.0 years)

* Delivery backlog for B3 data = 23 months (with respect to planned schedule). B3 data for 132 months have been archived.

* Delivery backlog for new DX/D1/D2 data = 41 months (with respect to planned schedule). C1/C2 data for 96 months have been archived. D1/D2 data for 48 months have been archived.