from south to north, —0.05, -0.73, —0.74, -1.16, —1.20 and 

 -1.42° C. 



"Wliile there is no overlap in surveyed area between the first and 

 second, sUfvej^s, comparison of the southern end of figure 14 with the 

 northern part of the first survey presented in figure 13 shows marked 

 similarity from the 970.9-dynamic meter contour near 46°10' W., 

 westward to the 971.0-dynamic meter contour. Westward of this, 

 however, figure 14 shows a movement westward onto the banks in 

 dynamic heights greater than about 971.01 dynamic meters. Thus 

 the chances of a deep draft berg moving south of the 47th parallel 

 along the eastern edge of the Grand Banks were much less than usual. 

 The swiftest current found during the second survey, both as indicated 

 by GEK and dynamic topography, was in the axis of the Labrador 

 Current as it crossed the first section between stations 5836 and 5837. 

 In an area more than 60 by 150 miles in extent, in the northeastern 

 part of the surveyed area, the steady currents were practically non- 

 existent with a total range in dynamic height of about 4 centimeters. 



Figure 15 shows the dynamic topography found during the third 

 survey. Since no previous network survey of the area on the New- 

 foundland shelf north of the Bonavista triangle has ever been made 

 there exists no basis for comparison of this portion of figure 15 with 

 normal conditions. A few earlier sections, widely spaced, have sug- 

 gested tbe presence of an eddy. The principal interest, from a stand- 

 point of practical application of oceanography to Ice Patrol, lay in the 

 core of the Labrador Current near the continental slope and the area 

 southeastward of the Bonavista triangle at and just northward of the 

 latitude of Flemish Cap. Here figure 15, like figure 14, shows a 

 pronounced set onto the Grand Banks. This movement into shoaler 

 depths began as far north as 50° N., but was of practical magnitude 

 only south of 48° N. The colder water of the temperature minimum 

 of the Labrador Current apparently followed this path since the lowest 

 temperature found in the section from Flemish Cap to the Grand 

 Banks was —0.6° C. whereas temperatures as low as —1.48° C. were 

 observed in the southeastern section of the Bonavista triangle. Thus 

 the current in the water which is deep enough to permit passage of a 

 large berg had temperatures warmer than the optimum for lengthy 

 survival. In comparison to figure 14, there was an apparent westward 

 shift of the current pattern in the vicinity of tbe valley between 

 Flemish Cap and the Grand Banks. 



Figure 15 indicates that only such bergs as might cross the 49th 

 parallel west of about 52°30' W., would follow the western branch of 

 the Labrador Current and that any bergs crossing this parallel between 

 52°30' W., and about 49°30' W., would strand on the northern and 

 northeastern slopes of the Grand Banks. Of those crossing the 49th 

 parallel eastward of 49°30' W., it was expected that most would 

 recurve eastward north of the latitude of Flemish Cap. Figure 16 



68 



