32) on the same or preceding stations, except 

 at stations 28, 29, 54, and 55, where winds 

 were weak and variable. During periods of 

 strong northeasterly winds the flow at 10 m 

 (and less) was generally before the wind, 

 southwestward out of the Cape Lisburne-Icy 

 Cape area, opposite to the general flow ex- 

 pected. Whenever the northeasterly winds sub- 

 sided, the near-surface currents apparently 

 returned to a pattern of flow into the area, 

 toward the northeast. Evidence for this was 

 observed in the current measurements made of 

 stations 54 and 55, during a period of weak 

 and variable winds, and station 64 nearby, 

 during a period of strong northeasterly winds 

 (fig. 75) ; the former two stations showed 

 northeastward currents and the latter station 

 showed southwestward current. 



In the nearshore area between Point Lay 

 and Icy Cape the 10-m currents were weak and 

 widely variable. Because of the influence of 

 tidal currents, vessel's motion, and variable 

 winds, little significance can be given to the 

 current measurements, except that they lacked 

 the orderly alongshore flow expected. 



Near bottom currents (vector averages) 

 varied from the 10-m currents both in direc- 

 tion (up to 140° either to the right or left) and 

 speed (up to 0.38 kt) . Excluding the observa- 

 tions on stations 60 and 90 near Cape Lisburne 

 and station 26 near Icy Cape, however, the 

 near bottom and 10-m currents fell at least in 

 the same quadrant on the remaining 8 stations 

 and within the same octant on 6 of the 8. Near 

 bottom currents entering the area of study 

 were found only on stations 54 and 55, indicat- 

 ing that they were influenced by the north- 

 easterly winds, as was the case for the 10-m 

 currents. 



The difference in direction (figs. 60 and 74) 

 between currents at 10 m and near bottom was 

 pronounced during the entire period of 

 measurement (30 hours) on station 8. During 

 the first 5 hours both meters were deployed, the 

 directions differed by about 90°. During the 

 next 16 hours the directions differed by 90- 

 180°. During the last 10 hours the directions 

 differed generally by less than 45° and at times 

 were nearly coincident. The significant changes 

 in direction which occurred in both records did 

 not coincide in time, occurring at the 6-hour 

 mark at 10 m and at the 22-hour mark near 



bottom. Only 2 of 17 expendable bathythermo- 

 graph traces obtained at about 2-hour intervals 

 showed evidence of stratification. 



Inference from Distributions of Water 

 Properties 



The apparent asynopticity of observations 

 over the full cruise period makes it fruitless to 

 attempt extensive inference of flow patterns 

 from the distributions of water properties. The 

 general absence of the parallelism between 

 property isopleths and isobaths, as had been 

 found by previous investigators (Aagaard, 

 1964, and Fleming and Heggarty, 1966) , 

 clearly showed that a I'egime of orderly along- 

 shore flow did not exist during WEBSEC-70. 



SUMMARY OF CONCLUSIONS 



1. Pronounced changes in wind velocity and 

 air temperature during the 23-day sampling 

 period produced measurable changes in the 

 distributions of water properties, rendering 

 the oceanographic data collected decidedly 

 asynoptic. 



2. Distributions of temperature, salinity, 

 dissolved oxygen, and nutrients showed the in- 

 fluences of Alaskan coastal runoff, melting of 

 sea ice, freezing of sea ice, and bottom water 

 from the central Bering Strait. 



3. Distributions of dissolved nutrients 

 showed horizontal gradients which may have 

 been the result of photosynthetic activity in the 

 upper 10 m of moving water. However, if this 

 was the cause of the observed gradients, the 

 residence time of water in this area of the 

 Chukchi Sea must have been longer than the 

 10 days estimated by Fleming and Heggarty 

 (1966). 



4. Currents at 10 m and near bottom were 

 found to be strongly influenced by the wind. 

 Significant northeastward currents (to be ex- 

 pected from average charts) entering the area 

 of investigation were found only on two sta- 

 tions, during a period of weak and variable 

 winds. Currents ranged from southwestward 

 to northwestward during periods of strong 

 northeasterly winds. 



5. Currents near shore (15 miles off) be- 

 tween Cape Lisburne and Icy Cape were gen- 

 erally weak and variable, suggesting the 

 possibility of an eddy or pocket of slack water 

 northeast of Cape Lisburne. 



10 



