to the April minimum of the western section being so much suppressed 

 that the preceding maximum, which would correspond to the winter 

 maximum of the western section, is missing completely. Comparison of 

 the two sections month by month shows only a general correspondence, 

 but outstanding features in the fluctuations at the eastern section are 

 repeated at the western section about 9 months later. Thus the extreme 

 maximum and minimum difference in sea level between Horta and 

 Lagos for the period 1932-36 occurred during November 1933, and 

 January 1934, respectively, and the corresponding extremes in Bermuda 

 minus Charleston for the period 1933-37 occurred during August and 

 October 1934. Yearly means for the 4 years, April 15, 1932, to April 

 15, 1936, and 1933-36 do not show any recognizable correspondence 

 between the two sections, but the number of points is so small and the 

 probability of strong modifying factors existing intermediate between 

 the two sections is so great that it is believed we can safely conclude that 

 a time lag of about S}4 months does exist between the Horta-Lagos 

 section and the Bermuda-Charleston section. 



Thus we cannot regard the North Atlantic eddy as a rigid wheel but 

 must look upon it as a system in which local fluctuations in volume of 

 flow are temporarily accommodated by accelerations in boundary 

 waters which can be considered as storage basins. If most of any change 

 in the sea level gradient is accounted for by a change in the peripheral 

 sea level, then most of the corresponding change in volume of flow is 

 accounted for by peripheral boundary water accelerations. The rate of 

 progress of these fluctuations around the North Atlantic eddy is seen 

 to be about 8 or 9 months from the southeastern part of the eddy to the 

 Bermuda-Charleston section and about 5 months from the Bermuda- 

 Charleston section to the Grand Banks region. The location of the 

 cause of a fluctuation in volume of flow will determine the extent and 

 type of change in the T-S characteristics of the water constituting the 

 outer boundary of the eddy so that we should expect to find fluctuations 

 in characteristics as well as fluctuations in position of the boundary 

 and fluctuations in volume of flow. Hence it is considered that the 

 criterion of 34.95°/oo salinity at temperature 6° C. in the Grand 

 Banks region, although somewhat affected by changing water character- 

 istics, does give a rough indication of the boundary of water movement 

 as well. From the standpoint of ice patrol, in which the disintegration 

 of bergs and the safe location of steamer lanes are of first importance, 

 as well as for practical climatological considerations, the location of a 

 boundary defined in terms of water characteristics is of greater value 

 than the location of an accurate boundary of water movement. 



From the foregoing, then, we have seen the possibility of predicting, 

 well in advance, that part of the shift in the boundary of the Atlantic 

 Current in the Grand Banks region which is dependent upon causes 

 associated with the North Atlantic eddy. In other words, the way seems 

 open to the prediction of the adjusted area. For the prediction of the 



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