0°C, reflecting the presence of or nearness to sea 

 ice cover. It should be noted that ACW may have 

 been found farther north than station 8. The 

 oceanographic stations occupied in the eastern 

 Chukchi Sea were very shallow ( <20 m) and close 

 to the continent so that the mass of ACW may not 

 have been observed. This is indicated by a tem- 

 perature maximum (2.23°) observed at 20 meters 

 at station 14 east of Point Barrow, Alaska (fig. 7). 

 The presence of this warm, relatively saline 

 (31.8°/oo) water at station 14 probably indicates 

 the advection of Bering Sea water from the Bering 

 Sea into the Beaufort Sea. The presence of a slight 

 temperature maximum (0.32°C, 32.01°/oo) at sta- 

 tion 15 (see appendix) probably indicates the 

 eastward extent of the advection for this time of 

 year. It was the location of the warm layer at 

 station 14 and 15 that influenced the position of 

 the moored current meters used during 

 WEBSEC-72 later in the season. A detailed dis- 

 cussion of Bering Sea water can be found in the 

 previous article in this book (Physical Oceanog- 

 raphy of the Western Beaufort Sea). 



In the eastern Chukchi Sea those temperatures 

 of less than — 1.0°C with salinities greater than 

 32.0°/oo probably represent Bering Sea Deep 

 Shelf Water (BSDSW) of Saur et al. (1954). This 

 water mass is believed to be formed in the winter 

 and is not normally found north of the Bering 

 Strait after July. 



The near-bottom water found at station 9 (fig. 

 8) in the eastern Chukchi Sea may have come 

 from the East Siberian Sea instead of the Bering 

 Strait. Codispoti and Richards (1968) found that 

 East Siberian Sea Water (ESSW) had a tempera- 

 ture and salinity range of —1.6 to — 1.8°C and 

 32.3 to 33. 4°/ 00. The water from 15 m to the 

 bottom (40 m) at station 9 was nearly isothermal 

 (-1.57 to -1.62°C) and isohaline (32.90 to 

 32.95°/oo). It was 0.5°C colder and slightly less 

 saline than BSDSW observed farther south. The 

 water was also lower in dissolved oxygen (<7.9 

 ml/1) then surrounding waters. 



Surface temperature and salinity values ob- 

 served east of Point Barrow in the Beaufort Sea 

 reflect the onset of icemelt and river runoff. 

 Temperatures were generally at or near 0°C with 

 salinities varying from 4.9 to 26.7°/oo (fig. 6). A 

 subsurface temperature minimum layer ( — 1.4 to 



— 1.6°C) of about 5 meters thick was observed at 

 many of the Beaufort Sea stations at 10 meters 

 depth. The cold water sandwiched between 

 warmer waters forms a dicothermal layer (Defant, 

 1961). This layer is due to the limitation of the 

 winter convection process by the high stability of 

 the water column. This suggests that the depth of 

 winter convection in the southern Beaufort Sea for 

 1971-72 was in general less than 15 meters. 



REFERENCES 



Aagaard, K. (1964) Features of the physical oceanography 

 of the Chukchi Sea in autumn. M.S. thesis. University of 

 Washington, 28 pp. 



Coachman, L. K. (1968) Physical oceanography of the 

 Arctic Ocean, in: Arctic Drifting Stations, J. E. Sater, 

 Arctic Institute of North America: 255-280. 



Coachman, L. K. and R. B. Tripp (1970) Currents north of 

 Bering Strait in winter. Limnology and Oceanography 

 Vol. 15(4), 625-632. 



Codispoti, L. A. and F. A. Richards (1968) Micronutrient 

 distribution in the East Siberian and Laptev seas during 

 summer 1963. Arctic, 21(2), 67-83. 



Defant, A. (1961) Physical Oceanography Vol. 1, Per- 

 gamon Press, New York, 729 pp. 



Fleming, R. H. (1959) Oceanographic survey of the East- 

 ern Chukchi Sea, 1 August to 2 September 1959, Pre- 

 liminary Report of Brown Bear Cruise No. 236, Univers- 

 ity of Washington, Dept. Oceanog. Ref. No. 59-30. 



LaFond, E. C. and D. W. Pritchard (1952) Physical 

 oceanographic investigations in the eastern Bering and 

 Chukchi Seas during the summer of 1947. Jour. Mar. 

 Res., 11, 69-86. 



Saur, J. F. T., Tully, J. P. and E. C. LaFond (1954) 

 Oceanographic cruise to the Bering and Chukchi Seas, 

 summer 1949, Part IV Physical Oceanographic Studies. 

 U.S. Navy Electronics Laboratory Research Report 

 416, Vol. 1. 



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