the May survey section W showed similar characteristics with the volume 

 of flow of 0.44 being 3.26 million cubic meters per second below normal 

 and a mean temperature of 5.25° C. which was 2.65° above normal. Dur- 

 ing the June survey the Labrador Current at section T was found to have 

 a volume of flow of 1.19 million cubic meters per second or 1.67 below 

 normal. Section U, also occupied during the June survey, showed a 

 volume of flow of 3.47 milhon cubic meters per second, which was 1.42 

 below normal, and the mean temperature, 2.31° C, was 0.03° above 

 normal. 



Thus each of the four occupations in 1948 showed a smaller than normal 

 volume of flow of the Labrador Current. The almost complete absence 

 of the Labrador Current at section W is in accord with the unusually 

 high mean temperatures found at that section. The location of the 

 boimdary zone between the Labrador Current and the Atlantic Current 

 depends on their relative strengths. The extra northerly location of this 

 boundary at section W, therefore, does not reveal whether the former was 

 weaker than usual or the latter unusually strong. However, the smaller 

 than normal volumes of flow of the Labratlor Current past sections U 

 and T give more reliable evidence that this weakness was a major de- 

 termining factor in the location of the boundary zone. It is of interest 

 to note that the forecast was for a smaller than normal number of bergs 

 during the 1948 season. As the forecast formulae are based on baro- 

 metric pressure distribution they predict fluctuations in the wind- 

 driven current system which provides transportation for the l)ergs without 

 direct consideration of the number of bergs to be transported. Thus a 

 forecast of a small number of bergs is, in effect, a forecast of a weak 

 Labrador Current. The subnormal volume of flow found at section T 

 is in accord with the berg forecast and indicates that the greater than 

 average number of bergs which actually crossed the 48th parallel was 

 not the result of better transportation facilities and that the reason must 

 be sought either in an al^normal suppl>' of bergs available for trans- 

 portation or a lower than usual mortality rate of the bergs during their 

 journey. 



Li this connection it is of further interest to note that the mean tem- 

 perature of the Labrador Current at Section T was 0.68° colder than 

 normal. The Labrador Current is made up of a frigid portion located 

 over the continental shelf and originating in the Baffinland Current, and 

 a warmer portion located over and seaward of the continental slope and 

 originating in the West Greenland Current. The lower than normal 

 mean temperature of the Labrador Current at section T suggests that the 

 deficiency in volume of flow was largely the result of a deficiency in the 

 West Creenland Current component. It is possible that this reduction 

 in the tempering effect of the West Greenland Current component may 

 have had an important effect in decreasing the berg mortality. 



Northward of th(» Grand Banks the Lalirador Current divides into a 

 western and usually minor bianch which flows southward along the 



78 



