Changes in the RTG_SST analysis

Description of changes effective September 14, 2010

The source of NAVY SST retrieval data was changed from NOAA-18 to NOAA-19.

Description of changes effective February 17, 2009

The RTG_SST analysis state was modified using NAVY SST retrieval data. This was done as part of the replacement of the 1/12 deg. resolution RTG_SST_HR analysis and was aimed at maintaining the proper generation of ice in the sea-ice analysis.

Description of changes effective September 23, 2008

The source of NAVY SST retrieval data was changed from NOAA-17 to NOAA-18.

The filling of latitudes 88 N - 90 N with -1.8 deg. C was removed.

Description of changes effective May 6, 2004

The source of NAVY SST retrieval data was changed from NOAA-16 to NOAA-17.

Description of changes effective May 8, 2002

Array sizes for one week of in situ data were doubled from 90,000 to 180,000 in the program which performs quality control of in situ data.

The program in question was generating large numbers of messages indicating that buoy data were being dropped. This was due to insufficient array sizes. The effect was that up to 25% of buoy data were being dropped from the the most recent day's worth of data (i.e., the real-time buoy data). The buoys dropped were in the northern areas (off of Western Europe, the U. S. and Canadian East Coast, the Gulf of Alaska and the West Coast off the U. S. and Canada). The northernmost buoys started being lost around April 22.

Description of changes effective April 23, 2002

Instituted a smoother to eliminate 2-delta grid length waves, while leaving larger scale phenomena unchanged.

The reason for making this change is that small-scale noise in the RTG_SST analysis was growing noticeably with time. There was very little noise as of Febrary 2001, but it was increasing throughout the past year. The growth of the noise has been attributed to the growth of round-off error in the RTG_SST analysis.

Description of changes effective October 23, 2001

Change in the operational run-time from 2045 UTC to 2240 UTC; and change the window for admitting data to the analysis system, in order to ingest all SST data received up to analysis run-time.

The reasons for making these changes are: to synchronize the daily RTG_SST run-time with the 00 UTC EDAS and produce more timely SST fields for use by the 00 UTC Meso Eta model run. The previous operational run-time was 3 hours, 15 minutes before the 00 UTC EDAS, and most recent data in the previous operational RTG_SST was already 20 hours old.

Description of changes effective June 5, 2001

Switch from NOAA-14 MUT SST retrievals to NOAA-16 SEATEMP SST retrievals.

The reasons for making this change are: (1) switch to a high-resolution, higher quality SST retrieval from the Navy; (2) switch from the older satellite (NOAA-14) to the newer satellite (NOAA-16).

For additional information about data-management and analysis techniques, contact Robert.Grumbine@noaa.gov.

For information about the run cycle and digital data format, contact Bert.Katz@noaa.gov.