the velocity of the Labrador Current was found to have been much 

 greater than during the first survey. This was in large measure the re- 

 sult of an intensified Grand Banks whorl which absorbed the smaller 

 whorl and moved northward to center at about latitude 44°50 ' N. 

 In the southwestern edge of the map the conditions along the 50th 

 meridian were not strikingly changed since the first survey except 

 that it may be inferred that the westward extension of the Labrador 

 Current and the area of the cold mixed water west of this meridian 

 were both decreased. At the surface in this longitude the northern 

 border of the Atlantic Current was somewhat farther north than in 

 figure 2. Immediately eastward of this longitude the above-mentioned 

 decrease in the western area of cold mixed water was largely compensa- 

 ted for by a south-southeastward extension of a tongue of mixed water 

 forcing the 97 L 1-meter dynamic isobath slightly south of latitude 

 41° N., at about longitude 48°20 ' W., Northeastward of this area, the 

 waters along the border of the Atlantic Current were moving with 

 lower velocity and greater simplicity of pattern than was the case during 

 the first survey. Both of these results are probably attributable partly 

 to the period of quiet weather just before and during the survey, and 

 partly to the large volume of mixed water returning northeastward. 

 The Atlantic Current salient had moved northeastward about 80 miles 

 and the valley northeastward of the salient is recognizable at the extreme 

 northeastern edge of figure 3. 



The current map resulting from the third survey is shown in figure 4. 

 In the northern part of the map the Labrador Current shows about the 

 same number of dynamic centimeters difference in height as in the 

 previous survey. However, the width of the current was much narrower. 

 The Grand Banks whorl decreased in intensity as the advancing season 

 wiped out the differential warming of the waters over the shoal. This 

 accounts for a large part of the decrease in velocity of the apparent 

 Labrador Current at about latitude 44 to 45° N., compared with condi- 

 tions which existed during the previous survey. The area covered by 

 cold mixed water south and southeast of the Banks had decreased, 

 the decrease taking place chiefly on the southern border. The border 

 of the Atlantic Current advanced northward in nearly all of the eastern 

 half of the area surveyed. The Atlantic Current salient advanced slightly 

 toward the Banks and the valley forming the northeastern side of the 

 salient became more pronounced than in figure 3. It is of interest to 

 note that this year the changes in current pattern took place gradually 

 enough so that the major features, such as the Atlantic Current salient, 

 can be traced throughout the season, although only three current maps 

 are available. 



In continuation of the investigation of the seasonal variations of the 

 Labrador Current, reported on in previous bulletins of this series, the 

 volume of flow, minimum observed temperature, and mean temperature 

 of the Labi'ador Current have been determined for the 1941 occupations 



