nose of warm water is still seen. Station 138 has little mesocale 

 structure. Because of the discrete sampling at Station 91 the structure 

 is not visible but adjacent Station 95 (Fig. 23) has considerable 

 structure . 



Station 138 is a good example of the appearance of the shallow 

 and deep lowerings on one graph. There is creditable agreement between 

 the salinities on the two lowerings , although some change in water 

 structure in the intervening time is evident. Agreement is not always so 

 good, due principally to depth errors, which are in the vicinity of ±1.5 

 meters. This also is an example of a case in which the salinity has made 

 the sound velocity profile somewhat different in shape than the tempera- 

 ture profile. The difference in the vicinity of the change of slope at 13 m 

 depth is evident. An interesting phenomenon is the appearance of a 

 broad but weak sound channel between 13 and 37 meters because the 

 salinity has become isohaline prior to the temperature becoming iso- 

 thermal . 



Eastward in the Beaufort Sea the warm current has descended to 

 a deeper depth of equilibrium density and the temperature now increases 

 toward the bottom. Station 87 (Fig. 24) apparently is not far enough 

 north to demonstrate the core, but it shows 3.6°C water at 39m. At 

 this station the STD was out of operation and all the data is from the 

 RS5. Any mesocale structure is therefore obscured. However, Station 

 111 (Fig. 25) which is close by has a stepwise structure. 



The last point at which notably warm water was found was at 

 Station 129 (Fig. 26) where the temperature at 24 meters was 3.3 C and 

 some structure was still present. The stations on the Beaufort Sea shelf, 

 of which Station 126 (Fig. 27) is an example, are cold, with low sali- 

 nity and little structure. The water does warm a little toward the bottom, 

 however, indicating that some of the warm water has found its way onto 

 the shelf from farther offshore. 



Hufford's (1973) area of coverage begins at 154°W and extends 

 to 144° W. He succeeded in getting his outermost stations about 90 km 

 offshore, 18 to 55 km seaward of ours in the three degrees of overlap. 

 His findings complement ours neatly. He finds the warm water at depth 

 at his farthest seaward stations and his depths are great enough that the 

 core is clearly indicated as centered at about 25 meters depth with cold 

 water above and below. He finds warm water at least as far east as 

 1470 W and it appears that the warmest water is on the most northerly 

 margin of his survey area. This suggests that the core may be still 

 farther to seaward and that it may continue farther east at a distance 

 farther from shore than it is practical to penetrate with icebreakers. 

 Hufford also shows that warm water was found in a number of previous 



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