corrected sea levels so derived have been used in combination with the 

 Charleston records wherever actual measurements are lacking from 

 the Bermuda end of the section. In this way monthly mean values of 

 the difference in sea level between Bermuda and Charleston have been 

 determined for the period 1933-41. 



.. i 



Figure 14. — Mean seasonal variation in difference in sea level between Bermuda and Charleston com- 

 pared with mean seasonal fluctuation in the outer boundary of the Atlantic Current in the Grand Banks 

 region. 



A smooth curve based on these monthly means and representing the 

 seasonal fluctuation has been drawn as a solid line in figure 14. In- 

 terprteted in terms of volume of flow of the Gulf Stream, this curve 

 incidates minima in late April and October, and maxima in late July 

 and the beginning of January. In the same figure the seasonal fluctuation 

 in the adjusted area, given in table 2, is shown as a broken line passing 

 through four points, each representing the mean of all surveys for the 

 period 1934-41, between March 16 and April 15, April 16 and May 15, 

 May 16 and June 15, and June 16 and July 15, respectively, and plotted 

 against the mean time of the surveys. There appears to be a maximum 

 during June. As the curve is drawn, the maximum occurs during the 

 first part of the month, but it is evident that both the exact time and 

 shape of the maximum must remain indefinite until fixed by other 

 considerations than the four points shown in figure 14. 



From figure 14 it is seen that the maximum in adjusted area occurs 

 between the spring minimum and summer maximum in volume of flow 

 of the Gulf Stream. If the two phenomena are related, there is a phase 

 difference and the maximum in adjusted area may be associated with 

 any one of the four extremes in volume of flow of the Gulf Stream. 

 To determine which of the four involved a correlation with the adjusted 

 area, yearly averages were plotted with appropriate time lags between 



18 



