ture at the 50 meter level then approximately 

 coincides with the surface temperature until 

 April when it rises more slowly than the sur- 

 face temperature. 



The 100 meter temperature follows the same 

 general pattern reaching a maximum of be- 

 tween 4 and 5° C. in November. Once again 

 this is the same temperature as that of the sur- 

 face at this time. 



The 400 meter temperature also has a pat- 

 tern, but not quite the same as the upper lev- 

 els. The 400 meter level descends to a mini- 

 mum temperature (3.35° C) in April, and then 

 increases gradually. At the end of December 

 its temperature is higher than that in the 

 upper levels. It then decreases and continues in 

 the same general pattern. 



The vertical salinity envelopes are presented 

 in figures 22-30. As shown in figure 22, the 

 surface salinity during October 1966 ranged 

 from 34.56 to 34.66%o with the halocline situ- 

 ated between 100 and 300 meters. Below this 

 level there was an inversion extending down 

 to about 600 meters of about 0.04"/oo/300 meters. 

 Below the inversion the gradual increase in 

 salinity with depth continued. 



From November through March there was a 

 gradual increase in the surface salinity with a 

 corresponding increase of the mixing depth. 

 During the 24 November-12 December 1966 pa- 

 trol of the USCGC McCULLOCH the surface 

 salinity increased to a range of 34.61-34.66%o 

 (figure 23). The mixing depth had increased 50 

 meters over that of the previous month to 100 

 meters. 



Through the month of January the surface 

 salinities increased to a range of 34.67-34.85 

 %o. A fairly large gradient was present dur- 

 ing the first part of the month. However, by the 

 end of January this had been reduced sub- 

 stantially with mixing occurring down to 300 

 meters (figure 24). 



Figure 25 shows a column of isohaline water 

 whose lower limit varied between 400 and 550 

 meters. The surface salinities ranged only 

 from 34.79 to 34.83%o. 



By April the halocline had all but disap- 

 peared and the surface salinities had again in- 

 creased, the range at that time being 

 34.82-34.86%o. This relatively isohaline col- 

 umn quickly disappeared in May as indicated 

 by figure 27. The surface salinity dropped 



(34.75-34.84%o) and maxing occurred only in 

 the upper 100 meters. The next four months 

 experienced a continual decrease in surface sal- 

 inity, greater salinity gradients, and a decrease 

 in the mixing depth to 50 meters. 



The monthly averages of salinity for 4 levels 

 (0,50,100,400 meters) are plotted in figure 81. 

 As was seen in the corresponding plot for tem- 

 perature, there are definite variations that 

 occur within each year. The surface salinity 

 reaches a minimum in September (;=::34.52 

 %o). The salinity then increases until Novem- 

 ber after which there seems to be a secondary 

 salinity minimum in December. There is a 

 rather sharp increase in salinity in January 

 which then becomes more gradual until a maxi- 

 mum is reached in April. 



The variation of salinity at the 50 meter 

 level is somewhat more erratic than at the sur- 

 face. The salinity minimum appears to occur in 

 October with a secondary minimum in Decem- 

 ber. Sufficient data have not been collected dur- 

 ing these winter months to accurately deter- 

 mine the complex variations of salinity for this 

 time of year. From December through May the 

 salinity at the 50 meter level follows the sur- 

 face salinity quite closely. There appears to be 

 another salinity minimum in August. 



At the 100 meter level the salinity minimum 

 occurs in December. There seems to be little 

 rhyme or reason for the monthly variation of 

 salinity at the 400 meter level. This is probably 

 due to the fact that the 400 meter level is not 

 directly influenced by surface effects, but is in- 

 fluenced by lateral motion and diffusion in- 

 stead. 



In Figure 32 are plotted the annual varia- 

 tions of temperature at various depths for the 

 period from January 1964 to October 1967. 

 This plot tends to bring out the striking simi- 

 larity of the temperature variation each year. 

 Figure 33 is a similar plot for salinity. Once 

 again this similarity is noticed. 



Summary 



The nine patrols at Ocean Station BRAVO 

 during the period 8 October 1966-20 October 

 1967, plus data collected during previous pe- 

 riods, present a fairly clear picture of the vari- 

 ations of temperature and salinity vs. depth. 

 The monthly and seasonal variations of tem- 

 perature, and to a lesser degree salinity, have 



