b. Salinity 
The range of surface salinities in this area was from 32.38 to 34.00%,,. 
In the upper 200 meters, salinities increased rapidly to 34.50, with 34.00 through 
34.259, appearing in the area of minimum temperatures. Salinities continued to 
increase with depth to a maximum of akout 34.749, at approximately 800 meters and 
decreased to a minimum of 34.68%, near the bottom. 
c. Sigma-t 
Surface sigma-t values less than 27.00 were observed at the stations 
east and north of station 49; to the west and southwest, values were slightly greater. 
Within the upper 100 meters, values increased rapidly to 27.50 at all stations. The 
27 .75 isopycnal occurred between 200 and 400 meters, and below this, sigma-t 
values increased slightly to maximum values of 27.87 near the bottom. Sigma-t 
values appeared to be very uniform horizontally throughout the area. 
d. Dissolved Oxygen 
Dissolved oxygen content in the surface water was greater than 
7.00 ml/I at all stations, except stations 42, 43, and 44 (Fig. 14). Below the 
surface, oxygen values decreased rapidly to about 400 meters, where minimum values 
of about 4.00 ml/I were observed. At stations 50, 51, and 55, oxygen minima were 
less than 4.00 ml/I. Below this minimum layer, oxygen content increased to the 
bottom with values approaching 5.00 ml/I. 
3. Dynamic Topographies 
Considering the oxygen minimum layers as indicative of levels of no motion, 
a plot of 6xygen minimum values shows the levels of no motion to be in the vicinity 
of 350 to 800 meters in the western portion of the area surveyed, and to slope down- 
ward to the south. In the eastern portion, depths of minimum oxygen varied. This is 
an area of strong counterclockwise circulation, where considerable differences are 
found in dynamic heights at the same standard depths between any two stations, 
especially below 500 meters. 
Because of the amount of variability between eastern and western sectors of the 
area, the reference level was selected as the greatest depth reached at most of the 
stations, which in this case was 2,500 meters. As a check, dynamic height charts 
were plotted using different reference levels, and they depicted a similar circulation 
pattern. 
27. 
