of the advancing season's low, the waters have the characteristic 

 structure of the summer monsoon. 



The seasonal upwelling off the coast of the Somali Republic also 

 may be indicated by the presence of clouds. In this area, the general 

 cloud pattern is related to the monsoonal wind pattern, which in turn 

 governs the beginning and end of the upwelling. Thus, the cloud 

 pattern may be used to indicate the probable duration of upwelling. 



An analysis of mean historical data indicates that seasonal 

 upwelling along the coast starts in May and ends in November. The 

 question, however, for any particular year is, "When in May does it 

 start and when in November does it end?" The monsoonal pattern of 

 clouds in ESSA 3 pictures (Figure I3) shows that in I967 upwelling 

 probably started before 28 May and that some upwelling may still have 

 been occurring on 25 November. 



In addition, examination of the low cloud cover visible in ESSA 

 pictures during the period of upwelling shows the characteristic demarcation 

 of the clouds made by the cold and warm water (Figure Ik). 



Of course, all of the cloud patterns peculiar to a region are not 

 necessarily associated with the conditions of the water below. However, 

 by combining the knowledge of a region's cloud patterns as shown by 

 satellite pictures with a good comprehension of its physical conditions, 

 one may determine the oceanic temperature conditions of the region. 



Two television systems have been successfully used aboard polar 

 orbited satellites: The Automatic Picture Transmission (APT) and the 

 Advanced Vidicon Camera System (AVCS). These systems are being used on 

 the ITOS satellites. 



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