On November 21, 1997 the following changes were made to the GOES retrieval algorithm: o reject retrieval if the cloud-cleared observed channel 8 (IR window) value is 1.5C colder than the calculated value from the first guess
o fully use the AVHRR SST in the retrieval algorithm, not just the cloud-clearing step
o flag retrievals if we did not have the AVHRR SST value (RT=25)
Examples:
o The highlighted red boxes denote retrievals that are eliminated with the new method.
o The ocean retrievals without a background SST are plotted in yellow. One such retrieval is highlighted by a yellow box. The GOES-8 'new method' image demonstrates the situation where most retrievals without an SST value are not cloud-contaminated, but the retrieval hightlighted by a box may be.
GOES-8 sounder Skin Temperture -- Old Method 21 Nov 1997
GOES-8 sounder Skin Temperture -- New Method 21 Nov 1997
GOES-9 sounder Skin Temperture -- Old Method 21 Nov 1997
GOES-9 sounder Skin Temperture -- New Method 21 Nov 1997