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DEEP SCATTERING LAYER 



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00:00 

 21 JULY 47 



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FIGURE 41. Development of the deep scattering layer in the North Pacific on 20 and 21 July 1947 at 150 to 175 fathoms indicated depth scale would be in- 

 creased by a factor of 5). Note descent of the scotterers beginning before sunrise to form the layer and ascent beginning shortly before sunset but not reach- 

 ing the 60-fathom line until well after sunset. Note, also, the development of double layers at 0700 and 1300 hours. Although most of the scotterers rise with 

 nightfall, this fathogram shows the unusual development of a layer throughout the night. 



86 



