area using many vague definitions and names for 

 the water masses resulting in some confusion in 

 the literature. Classification of any water mass 

 may be valid only in a particular area and for that 

 particular season. 



The average flow of water through the Bering 

 Strait into the Chukchi Sea is about 1 X 10^ m^ 

 sec~^ (Coachman, 1968). This water flows north- 

 ward tending to follow the Alaskan coast and 

 dominates the circulation pattern in the eastern 

 Chukchi Sea. LaFond and Pritchard (1952) were 

 able to trace Bering Sea water in the summer into 

 Kotzebue Sound where it then headed around 

 Cape Lisburne toward Point Barrow. The cruise of 

 the BROWN BEAR in the summer of 1959 (Flem- 

 ing, 1959) conducted an extensive investigation 

 of currents in the eastern Chukchi Sea. Speeds up 

 to 150 cm/sec were reported north of Point Hope 

 Alaska. Weak anticyclonic eddies were found 

 northeast of the major Alaskan capes. 



There have been no extensive programs of cur- 

 rent measurements in the eastern Chukchi Sea in 

 the fall or winter months. Coachman and Tripp 

 (1970) have reported on current measurements 

 made through the ice in an area approximately 

 140 nm southwest of Cape Lisburne. Their results 

 indicated a northward flow, the same as in the 



summer. 



METHODS 



Two XBT sections were taken from the CGC 

 GLACIER on 12-15 August and 18-20 Sep- 

 tember 1971 (figs. 1 and 2). The XBT drops were 

 calibrated with bucket thermometer readings. 

 The first section in August (13 lowerings) was run 

 from Bering Strait to Point Barrow, Alaska. The 

 second section in September (43 lowerings), was 

 taken in the opposite direction. 



The CGC STATE N ISLAND operated from 

 Bering Strait to northeast of Prudhoe Bay in the 

 Beaufort Sea from 1-17 July 1972. A total of 23 

 hydrographic stations and 34 XBT lowerings were 

 taken in water depths rarely exceeding 60 meters 

 (fig. 3). At each station, a Nansen bottle cast was 

 taken to obtain measurements of temperature, 

 salinity, dissolved oxygen and inorganic nutrients 

 (PO4, NO3, NO2, SiOa). Observations were ob- 

 tained at 5 meter intervals from the surface to near 



bottom on each cast. XBT lowerings were taken 

 every 3 hours from Bering Strait to Point Barrow, 

 Alaska, then every 30 miles from Point Barrow to 

 Prudhoe Bay. A detailed discussion of sampling 

 methods can be found in the previous article of 

 this book (Physical Oceanography of the Western 

 Beaufort Sea). 



RESULTS 



CGC GLACIER XBT Sections 



Examination of temperature from the XBT sec- 

 tion taken from just east of St. Matthew Island in 

 the Bering Sea to Point Franklin, Alaska in the 

 Chukchi Sea, 12-15 August 1971, showed that 

 Bering Sea water could be traced as far north as 

 Point Franklin (fig. 4). The 6°C isotherm outlines 

 the lower boundary of Alaskan Coastal Water 

 (ACW) of Saur et al. (1954) and can be easily 

 traced northward. It is interesting to note that the 

 temperature range of the warm water mass in the 

 Beaufort Sea in August, 1971 was 0. 1 to 5°C (see 

 preceding article). 



Examination of the XBT section over essen- 

 tially the same course track in 18-20 September 

 1971 indicated that Bering Sea water could be 

 traced north only to Cape Lisburne, Alaska (fig. 

 5). This suggests that if the warm water mass in 

 the Beaufort Sea is Bering Sea water then input to 

 the warm water mass (>0°C) ceases by mid- 

 September as would be expected with the onset of 

 autumn. 



CGC STATE N ISLAND Cruise 



The temperature and salinity values observed 

 from the Bering Strait to Point Barrow July, 1972 

 (fig. 6) corresponded with water mass properties 

 defined by Saur et al. (1954) for the area except 

 that slightly cooler temperatures were recorded. 

 The surface water from Bering Strait to station 8 

 (fig. 3) appeared to be Alaskan Coastal Water 

 (ACW). This water mass occupied only the upper 

 10 meters of the water column instead of the 

 entire depth as seen later in the summer. Tem- 

 peratures varied from 0.1 to 5.9°C and salinities 

 ranged from 29.0 to 31.47oo. North of station 8, 

 surface temperatures were generally less than 



174 



