shown in figure 8 does not have a reliabihty comparable to that 

 of the dynamic topographic charts of the adjacent area to the 

 south. 



The western part of the surveyed area containing the triangle 

 beginning at station 4386 and with corners at stations 4397 and 

 4407 and closing at station 4415 is comparable to the earlier occu- 

 pations of this triangle in 1948, 1949, and 1950. Considering this 

 triangle in this sui'vey it would appear that any bergs entering 

 the area and crossing the 49th parallel east of about 51° W., would 

 follow the eastern branch of the Labrador Current, that those 

 crossing this parallel west of about 51°50' W., would follow the 

 western branch, and that those crossing at intermediate longi- 

 tudes would strand on the northern edge of the Grand Banks or 

 be set in toward the banks at about the 47th parallel. Of those 

 following the eastern branch, bergs crossing the 49th parallel east- 

 ward of 48°50' W., would drift eastward and northeastward north 

 of the latitude of Flemish Cap. 



The dynamic topographic chart resulting from the third survey, 

 figure 9, presents a different picture from that of the first survey 

 made about 7 weeks earlier. In the third survey Labrador Cur- 

 rent water was reaching the Tail of the Banks. The Atlantic 

 Current water salient, while not having the strength nor the high 

 temperatures encountered during the first survey, was still promi- 

 nent and effective in diverting eastward some of the Labrador 

 Current water northward of the 44th parallel. Were it not for 

 the absence of bergs entering the area, figure 9 would have indi- 

 cated midseason conditions with danger areas southwestward of the 

 Tail of the Banks, southward of the surveyed area at about longi- 

 tude 48° W., and eastward of the surveyed area north of about 

 latitude 44°30' N. The northern part of the surveyed area overlaps 

 the southeastern part of the area covered by the second survey 

 and comparisons of the results of the two surveys in this area will 

 be made in the discussion of the volumes of flow of the Labrador 

 Current. 



It should be noted that in the past there has been evidence of a 

 gradual progress northeastward of meanders such as the salient 

 of Atlantic Current water. The rate of progression has been esti- 

 mated to be of the order of magnitude of a few miles a day. With 

 an interval of about 7 weeks elapsing between the first and third 

 surveys, one might expect that the meanders found during the 

 first survey would be displaced perhaps 200 miles to the northeast- 

 ward in the third survey. Thus there is no assurance that the 

 salient of Atlantic Current water found during the third suivey 

 is the same meander shown in figure 7. If it is, we have here an 

 unusual case of stagnation or stability of current pattern. 



204964—53—5 



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