NUMBER 97

DATE: 09/04/91

Sector Processing Center (SPC):

During July, NOA, ESA and JMA processed greater than 99% of A data into B1/B2 data.

Normal operations were reported by NOA, ESA and JMA. No report was received from AES.

NOA reported continuing investigation of a change in the content of the NOAA-10 Stage A dataset. Since NOAA-10 has a 4-channel AVHRR, the radiance counts reported in the Channel 5 position are supposed to be a duplicate of those for Channel 4, which has been the case until now. In May 91 the GPC received B2 data with a "fill" count value replacing the Channel 4 data in the Channel 5 position. The reason for this change in the B2 is not known and it has been discovered that the count values in the Stage A dataset are not precisely identical. This problem does not affect the data quality for ISCCP as far as can be determined.

ESA reported that operations continued with METEOSAT-4 during July.

CSU reported beginning construction of a ground station to receive data transmissions directly from METEOSAT-3 at 50 W (called METEOSAT-50); the station is expected to become operational by November. In the meantime, collection of these data through NOAA channels (broadcast through GOES-6) is being attempted.

Special Area Processing Center (SAPC):

No reports were received.

Satellite Calibration Center (SCC):

The SCC reported receiving the following AC datasets: June 91 for NOAA-11, July 91 for GMS-4, and April through July 91 for GOES-7. BC data for April 91 were sent to the GPC for GMS-4 and METEOSAT-4.

Global Processing Center (GPC):

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

Production of NOAA-11 (preliminary) B3 data is current. NOAA-11 B3 data have been re-calibrated through June 91; however, checking of the IR calibration for the past six months and examination of the VIS calibration and aircraft results are continuing.

Production of NOAA-10 (preliminary) B3 data is current. Re-calibration of NOAA-10 B3 data has been completed through June 91; however, checking of the IR calibration for the past six months and examination of the VIS calibration are continuing.

Production of METEOSAT (preliminary) B3 data is current.

Production of GOES-7 (preliminary) B3 data is current. Since there are several significant gaps in the GOES-7 dataset, especially in the first few years, additional data have been requested from UWS for 87 and 88 and from CSU for 89 and early 90. The additional data have been already received from CSU and are being processed for merger with the AES dataset. Re-calibration of GOES-7 data has been completed through June 89; shipment to the ICA will be made after merger of the CSU images.

Production of GMS-4 (preliminary) B3 data is current.

The processing software to convert INSAT-1 B2 data into B3 format is being tested.

Production of TOVS and the ice/snow correlative datasets is current.

C1 data for May, June and July 88 have been completed and shipped to the ICA. With the faster CPU, production at about 3 months per month seems feasible.

THE FIRST FIVE YEARS OF ISCCP DATA HAVE BEEN COMPLETED!

At the end of our 8th year of data collection operations, we have reached a major milestone with the completion of data processing for the originally planned ISCCP dataset for July 83 through June 88. Congratulations are deserved for all current and past data center representatives and personnel. You should all celebrate.

A paper describing the radiance normalization procedures for ISCCP has been completed and will be submitted for publication in the Journal of Atmospheric and Oceanic Technology. The revised version of the documentation for the C1 and C2 datasets is about to mailed out by WMO.

ISCCP Central Archive (ICA):

The ICA continued to receive B1 data from NOA, AES, ESA, and JMA and B3 and C data from the GPC in a routine manner.