the case in the Grand Banks region during the season. 



Figure 29 shows the temperature distribution found in the South 

 Wolf Island-Cape Farewell section in 1948. The Labrador Current may 

 be recognized in the cold water core over the shelf and the warmer 

 offshore portion over the slope. On the Greenland side the cold in- 

 shore part of the West Greenland Current does not extend very far sea- 

 ward but the warm Irminger Current component haf? temperatures 

 which are mostly less than 6°. Although the area in which the tem- 

 peratures are between 4° and 5° extends seaward beyond station 3705, 

 this warm water offshore is considered to be associated with the edge of 

 the Atlantic Current rather than with the Irminger Current component 

 of the West Greenland Current. This unsuual situation will be dis- 

 cussed in greater detail in connection with the circulation inferred from 

 volumes of flow past the various sections. 



This is the first occupation of the South Wolf Island-C'ape Farewell 

 section since the 1941 observations. The intermediate water of the 

 Labrador Sea in the summer time showed a characteristic temperature 

 inversion with minimum values which were consistently in the neighbor- 

 hood of 3.17° over the years 1934 to 1939. In 1940 the cross-sectional 

 area of this temperature minimum wa^ much smaller and had a value 

 nearly 0.1° warmer than previously. In 1941 the temperature increa,se 

 was maintained and the temperature inversion was not present. In 

 1948 the temperature inversion is present, but taking the section as a 

 whole the area occupied by the temperature minimum is small and less 

 noticeable than a deeper temperature maximum. During the 1948 

 occupation, the lowest temperature observed at depths between 500 and 

 1,500 meters was 3.35° C. Whether this may be taken as an indication 

 that the pre-war change in thermal characteristics of the intermediate 

 water was still present, or considered as a northward encroachment of 

 the borders of the Atlantic Current, the end result is the same in imply- 

 ing a reduction in area of that part of the Labrador Sea which may be 

 a wintertime source region for bottom water of the North Atlantic. 



The locations and numbers of the stations occupied in the Labrador 

 Sea and Davis Strait during the 1948 post-season cruise are shown in 

 figure 30 to facilitate the following discussion in which reference is made 

 to station numbers and sections. Figure 31 shows the dynamic topog- 

 raphy of the sea surface relative to the 1,500-decibar surface derived 

 from the stations shown in figure 30. Because of the considerable dis- 

 tances separating the sections it is not possible to give a detailed picture 

 of the circulation, but the major features of the current pattei'n form a 

 guide to the construction and interpretation of the vertical sections of 

 velocity. As noted above, the warm water centered around station 3705 

 is associated with the outer edge of the Atlantic ('urrent rather than 

 with the Irminger Current component of the West Greenland Current 

 and the offshore boundary of the West Greenland Current is located in 

 the vicinity of station 3706. Consid(>ration of the vertical section of 



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