There can be little doubt that this is a region which is ex- 

 ceedingly active oceanographically. The multiplicity of different layers 

 can come only from an interleaving of waters with nearly the same den- 

 sities but different temperatures. The melting of ice, cooling and dilut- 

 ing one type of water, must create these differences in relation to water 

 not so cooled. 



That structures typical of Station 66 extend well into the ice 

 may be seen in Figures 19 and 20. These are temperatures from a 23- 

 hour time series at non-uniform time spacings ranging from 1 to 1.5 hours 

 with an average of 1.3 hours. These are in the vicinity of the first ice 

 station on 2 and 3 August. Stations 17 to 35 are shown spaced 1°C apart. 

 These stations are in 6 oktas ice concentration about 30 miles inside the 

 one-okta contour. 



It is surprising to find this much structure so far inside the 

 the ice. It is seen that the one distinctly stable feature is the warm 

 nose at about 10 meters depth. An S-shaped feature (a secondary mini- 

 mum-maximum-minimum) between 18 and 25 meters depth persists to 

 some degree between Stations 28 and 34, a period of 6.5 hours. There 

 also is a distorted step just above the top of the deeper cold water 

 which is just at the bottom of these traces. Other smaller features 

 generally do not last for an hour. 



An estimate of size scale depends on relative water speed be- 

 tween the drifting ship and the water. Since the ship was tending the 

 ice camps at this time, the measurements of currents relative to the ice 

 reported by Garrison and Pence (1973) are appropriate. These authors 

 report relative water speeds varying between 0.5 and 0.8 knots at 20 m 

 depth and 0.25 to 0.75 knots at 10 m. One might estimate that the 

 speeds relative to the water near bottom might be as great as the speeds 

 of ice drift, which were as great as 1.5 knot. However, a cursory ex- 

 amination of the density structures shows no such currents distinctly 

 reflected in the geostrophy relative to the local near-bottom layers. The 

 currents near bottom therefore are probably of substantial magnitude and 

 it would be surprising if the speeds relative to the surface were much 

 greater than one knot. 



From the present data, therefore, it may be concluded that the 

 warm nose has wide distribution and the secondary feature below it has 

 dimensions approximating 10 nautical miles. The smaller features which 

 do not persist from curve to curve must be smaller than one nautical mile 

 in extent and they may be much smaller. 



On following the station plan to the points of deepest penetra- 

 tion into the ice. Stations 91 and 138 (Figs. 21 and 22), the residual 



32 



