in 1971, and is not greatly different than in 1971. The deep tempera- 

 tures are almost identical, -1.7°C. In 1972 the near bottom salinity is 

 33.00 o/oo, about 0.3 o/oo lower than in 1971. The surface salinity 

 is about 2 o/oo lower and the residual warm nose is less prominant. 



There is some tendency to be misled in making comparisons 

 with 1971 because the 1972 survey covered so much larger an area and 

 is charted on smaller scale. In 1972 most of the stations in and near 

 ice were farther west and north than those in 1971. Most of them, 

 then, are not in the main core of the coastal current, which was found 

 flowing close to the coast. Perhaps the best group to examine for 

 similarities is the sequence 106, 105, 107-114 (Fig. 37). The sequence 

 106-110 is roughly comparable to the group 75-91 of 1971 with the 

 difference that ice is lacking up to Station 110, except for scattered 

 large isolated floes up to 1000 m in diameter at an over-all concentra- 

 tion less than one okta. During the travel northward there was ice to 

 the west at some unknown distance usually greater than 5 miles. The 

 number of miles inside the margin therefore is shown as "-10?" for the 

 stations concerned. Just beyond Station 110 the ice concentration be- 

 came about one okta. Even at Station 113 the ship was subjected to a 

 little swell apparently arising from fairly open water to the east. At 

 Station 114 the ice concentration was up to two oktas. 



The entire region from Station 107 to 114 was one exhibiting 

 symptoms of large-scale break-up. The warm nose in the temperature 

 profile was present even as far north as Station 114, nearly 50 miles 

 farther north than the point of presumed eastward turning of the coastal 

 current into the Beaufort. This may be because it was a year of greater 

 melting than in 1971 or, conversely, the melting may have been a symp- 

 tom of greater northward transport of heat which might push the turning 

 point farther north. Still another possibility is that Brewer's (1942) 

 observation that the coastal current branches at a point north of Pt. 

 Barrow has some validity and we are observing the northerly (or north- 

 westerly) branch. 



The remainder of the survey area, outside the coastal current 

 was characterized by conditions similar to the coastal current as long 

 as the position was well outside the ice. The typical structure was a 

 warm layer, perhaps as warm as 10 C, often isothermal extending to an 

 exceedingly sharp thermocline which then rounded off to a constant 

 temperature of -1.65 to -1.75°C at depths greater than 20-40 mi. In 

 the most westerly portions of the area, cooling at the surface progressed 

 steadily on approach to the ice even though there was little or no ice 

 present south of the ice margin. This situation is summarized in Fig. 38 

 which nests the temperature plots from Stations 34-44 with a 1°C spacing, 

 stopping just short of the ice. It is interesting that the typical stair-step 



57 



