4. DATA PROCESSING 

 4. 1 General 



The data were generally extracted from the FMR tapes using the listing 

 program and were hand plotted onto blank mercator mapping paper. In so far as 

 feasible, these plotted data were corrected for data misplacement errors, following 



Q 



guidelines suggested by Sherr. In his report, Sherr discusses several classes of 

 misplacenaent errors together with methods for their recognition and correction. In 

 the mapping format, these errors cannot be detected, and hence may introduce some 

 pattern distortion. 



Initial analyses were performed without reference to existing maps of mean 

 monthly SST patterns or local currents. Later the analyst consulted maps of mean 

 temperature patterns and currents for the area in question, and used them to guide 

 the analysis, particularly in areas where the plotted data were ambiguous and 

 permitted a choice. In no case was violation of the plotted data pernnitted. These 

 subsequent re -analyses of previously run cases resulted in a significant improvement 

 in the correlation between IR and conventional temperature patterns without violation 

 of the data. 



When scientists at the Woods Hole Oceanographic Institute were consulted 

 regarding the resultant maps, it was noted that the IR temperature patterns were in 

 many ways similar to those seen in intensive conventional measurement programs 

 over relatively restricted areas. 



The Woods Hole personnel also suggested that, in cases of particularly noisy 

 data or nearly isothermal areas, averaging over 1 squares or larger, and possibly 

 over repeated passes, would often be appropriate. Such averaging must be carried 

 out with Sonne care, or snaall scale features and their changes in time will be quickly 

 lost. The validity of this suggestion will be demonstrated in several of the case 

 studies discussed later in this report. 



4. 2 Elimination of Cloud Contaminated Points 



Whenever a cloud or portion thereof falls within the field of view (approximately 

 thirty nautical miles diameter at zero nadir angle) of the TIROS radiometer, it will 

 prevent accurate nneasurement of the surface temperature. In these cases, the 

 temperature recorded by the radiometer would be intermediate between that of the 



