With this added criterion, it is seen that Lower Deep Water is present but undergoing 
a transition south of the Convergence; the band of maximum salinity rises sharply from 
about 2,000 meters to 400 meters. Here then is where Lower Deep Water becomes 
Antarctic Circumpolar Water, in a zone of transition about 150 miles wide in a north- 
south direction. 
In order to be identified as Bottom Water, the water must have a temperature less 
than 0.5°C and a salinity less than 34.7%,. Therefore, Bottom Water is not found in 
the Pacific-Antarctic area unless depth to bottom is of the order of 3,000 to 4,000 
meters. 
Thus, in the first 150 miles of the Pacific-Antarctic area, ina north to south 
direction, three separate water types may be found in Deep Water: Upper Deep 
Water, Lower Deep Water, which is undergoing transition, and Bottom Water. 
Beyond this point in a southerly direction there is no Upper Deep Water, and Lower 
Deep Water becomes the Antarctic Circumpolar Water which will be the only identi- 
fiable Deep Water if depths are not great enough for the existence of Bottom Water. 
B. Eastern Ross Sea Area 
1. General 
Thirty-one oceanographic stations were occupied in the eastern Ross Sea 
from Edward VII Peninsula (Cape Colbeck) northward to approximately 75°S and east- 
ward to Probable Island (E.D.). Of these, the twelve northernmost stations were in 
areas with sonic depths greater than 2,000 meters. The remaining stations were in 
areas with depths less than 1,000 meters except station 30, which was near the ice 
shelf in Sulzberger Bay, where the depth was 1,136 meters. Stations occupied 
within a radius of approximately 50 miles of Cape Colbeck had depths less than 500 
meters, as did stations 28 and 29 near Guest Island to the east. Stations 2, 3, and 
4, north of, and station 13, northeast of, Kainan Bay, were more than 500 meters 
deep. The 31 stations were occupied during the period 21 to 29 December 1960. A 
bottom contour chart is presented in Figure 3 based on bathymetric data collected 
during DEEP FREEZE 61. 
Five cross sections were selected to illustrate vertical distribution of physical 
and chemical properties in the Eastern Ross Sea. These are presented as Figures 4 
through 8. They consist of a west-east section of six deep stations (4, 000-meter 
profile), a section over the continental shelf (1,000-meter profile), a section of 
three stations to the west of Cape Colbeck (1,000-meter profile), and two selected 
north-south sections representing the line of stations farthest west, south to Kainan 
Bay and those to the east into Sulzberger Bay. Bottom profiles are from the ship's 
echo sounding trace and are drawn with five soundings plotted between stations . 
oe 
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