data. Our studies indicate that this can be done for daytime cases for overcast 

 or broken conditions. Areas of small scattered cloud, however, may erroneously 

 decrease the Channel 2 temperature values without being detected by Channel 5. 

 Nighttime detection of cloud points using Channel 2 and 4 differences is not presently 

 possible, and no alternative useful approach to the nighttime cloud detection problem 

 is yet apparent. The use of sharp changes in the Channel 2 values is insufficient, 

 since it may not reveal areas of low or scattered clouds. 



The pilot study off the western coast of Australia indicated that methods of 

 extensive data processing can usefully be applied to SST studies. The final map 

 in this study was produced by manually outlining clear areas and then hand averaging 

 point by point. With reasonable modifications of existing computer programs, this 

 tedious process can be automated, and individual or averaged clear sky maps 

 produced as a direct computer output. The human with his experience and knowledge 

 of local currents and mean temperature patterns is still required for the optimum 

 final analysis. We believe that, for comprehensive studies or operational uses of 

 SST, such extensive data processing techniques will be required. The application 

 of these techniques to satellite IR data can significantly increase our knowledge 

 of sea surface temperatures and their patterns, gradients, and variations over the 

 several scales of time and space at which they have significant scientific and prac- 

 tical applications. 



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