14 



crepancies in velocity as shown by drift and as computed. If any- 

 thing is to be learned or any conclusions drawn from this discussion 

 of figure 2 it would be briefly this: that 48 hours of northwest gales 

 introduce wind components approximately along the axis of the south- 

 bound current which may greatly accelerate the rate of flow, and this 

 effect must not be neglected. Also, that this effect is not a tempo- 

 rary one hmited to the duration of the storm but the impetus given 

 persists, as in this case, at least 10 days. It is suggested here that 

 such a powerful influence on the flow, as this seems to indicate, may 

 possibly be responsible for the final pattern of the current. (See figs. 

 45 and 46.) 



In discussing figures 3 and 4 it need only be pointed out that as the 

 season advances and conditions become less boisterous the corre- 

 spondence of berg drifts with the computed stream lines becomes more 

 and more satisfactory. In figure 3, after June 11, the correspondence 

 in both direction and velocity is good, the berg averaging 16.5 miles 

 per day, while the chart calls for 16.8 miles per day. That the berg 

 follows the stream lines well throughout the long drift of 350 miles 

 can be seen by inspection. Prior to June 11 the velocity shoMoi by 

 the berg is greatly in excess of the movement to be expected from the 

 current map. This is attributed to the gales of May 31 and June 1, 

 exactly 10 days previous. (See above.) This storm is an interesting 

 one and is discussed above on page 8. (See fig. 27.) In figure 4, 

 with quiet summer conditions prevailing, no more could be asked. 

 The berg drifted in almost exact accordance with the computed set 

 and drift on the map and each day's position of the berg could be 

 forecast within reasonable limits. (See figs. 31 to 33 and fig. 47.) 



Discussing berg drifts in relation to the current maps has led 

 inevitably to a consideration of the effect of wind on the movement 

 of bergs. In the past 6 or 7 years since the development of the tech- 

 nique for the construction of current maps at sea and their adoption 

 by the Ice Patrol as a tool the effect of wind on the drift of bergs has 

 unconsciously been minimized in an effort to prove the worth of the 

 new tool to those who might be skeptical. After all, there are only 

 two major forces contributing to the movement of bergs. Current 

 is one, and it must not be forgotten that wind is the other. The 

 intimate relationship between meteorology and oceanography is well 

 recognized and need not be stressed. The major role of the atmos- 

 pheric circulation over the Atlantic in maintaining the great Gulf 

 Stream system is established. In studying a means to foretell the 

 character of an approaching ice season, for instance the number of 

 bergs, the correlation factor was found highest between ice conditions 

 in the spring and wind in the Baffin Bay area the preceding winter. 

 The simple and more direct relationship of wind to berg drift is no 

 exception to this general rule. The current maps may be considered 



