DAVIS STRAIT AND LABRADOR SEA 



141 



Greenland Current which enter into the composition of the Labrador 

 Current. Again in hite August 1928 the Marion found the Labrador 

 Current to be flowing with a vohime of 4.6 million cubic meters per 

 second. At the rate of 8.2 miles per day this discharge should have 

 reached the Grand Banks sector the following December. Thus 

 the evidence contained in the above quantative data strongly indi- 

 cates that the Labrador Current prevails in the Grand Banks sector 

 the year round. 



If, on the other hand, an acceleration of the dynamically induced 

 circulation occurs in the northern part of the Labrador Sea as 

 hypothesized (p. 186) , it would probably cause a subsequent augmen- 

 tation of the Labrador Current reaching its maximum in the Grand 

 Banks sector the following May. 



Figure 101. — The normal atmospheric pressure gradient, October to March, over the 

 Labrador Sea. The solid line represents the Belle Isle-Julianehaab gradient and the 

 broken line the Nain-Ivigtut gradient. 



The seasonal change both in the velocity and the direction of 

 the prevailing winds over the Labrador Sea appears to be one of 

 the most logical factors, if a spring freshet of the Labrador Current 

 is a reality. Fig. 101 indicates that the prevailing winds, which pro- 

 duce a tangential wind current, the main component of which is 

 southerly, attain their maximum effect in January. If a current is 

 thus formed, it will proportionately augment the prevailing dynamic 

 current which has been found there in summer and described as the 

 Labrador Current. At the rate of 8.2 miles per day, the estimated 

 velocity of the summertime current, such a flood wave would appear 

 in the Grand Banks sector in April and May. This coincides with 

 the date of the commonly supposed spring freshet. 



The foregoing raises the broad question whether or not such cur- 

 rents as the East Greenland and the Labrador exhibit a seasonal 

 variation. There is a well-established view that the Labrador Cur- 



