the sinking of surface vater at the Subtropical Convergence. The 

 southern limit of the Indian Ocean Central Water is located at this 

 convergence^ south of vhich the Central Water is not present. In 

 the region of the convergence the surface salinity and temperature 

 vary rapidly vith latitude and the horizontal T-S relation at the 

 surface agrees very veil with the vertical T-S relation vithln the 

 Central Water mass during certain seasons.^ A remarkable feature 

 of this vater mass is that nearly all temperature and salinity 

 observations fall on a straight line betveen the points T = 8°, 

 S = 3i^.60^, and T = 15°^ S = 35.50^. Indian Ocean Central Water 

 extends over the entire vidth of the southern part of the ocean 

 and spreads north from the Subtropical Convergence which is located 

 at 35 - 40°S latitude. It is bounded on the north by a zone of up- 

 veiling of Intermediate vater at 12°S latitude. Temperature values 

 range from 8 to 19 ''C^ salinity is 3k. 60 to over 36.0^_,. and. the 

 absolute oxygen content is 0.21 to 2.O9 ml/l. 



Intermediate Vfater . In viev of the fact that the process of formation 

 of intermediate vaters involves the mixing of denser vater than in 

 the formation of subsurface vaters, the former occupy great depths 

 and underlie the subsurface vaters. Tvo intermediate depth vaters 

 are found in the southern Indian Ocean, the Antarctic Intermediate 

 Water and the Equatorial Intermediate Water. 



The Antarctic Intermediate Water is formed in the Antarctic 

 Convergence at about 50 °S latitude, vhere there is sinking of sur- 

 face water of the Antarctic region. This lov temperature vater has 

 sufficient density to sink to a depth of 1,000 to 1,600 meters. As 



^H. V. Sverdrup, Martin W. Johnson, and Richard H. Fleming, Thf. 

 Oceans (Prentice-Hall, Inc., Englevood Cliffs, N. J., 19^2), p. 69I. " 



54 



