WATER MASSES AND CURRENTS OF THE OCEANS 215 



which maintains a relatively high salinity down to depths exceeding 

 3000 meters, but to the south of the Equator the temperature-salinity 

 values indicate only a slight effect of the Red Sea Water. In the southern 

 part of the Indian Ocean an independent circulation must be present. 

 The deep water from the South Atlantic Ocean continues into the Indian 

 Ocean and is particularly conspicuous in the western part, where maxi- 

 mum salinities of 34.80Voo have been observed. This water flows mainly 

 toward the east, being somewhat diluted by admixtures of intermediate 

 and bottom waters. On the other hand, Antarctic Intermediate Water 

 flows north, and the bottom temperatures demonstrate that bottom 

 water also moves north, and these water masses must return again to 

 the south. It is probable that the intermediate water and the bottom 

 water mix with the deep water and that the return flow takes place 

 within the latter. A slight admixture of deep water from the region to 

 the north of the Equator that is compensated for by bottom water 

 penetrating across the Equator appears to maintain the salinity of the 

 Indian Ocean Deep Water at a higher level than would be the case if no 

 addition of saline water took place. Thus the influence of the Red Sea 

 can probably be traced to the Antarctic. 



From the Indian Ocean the Antarctic Circumpolar Water with its 

 components of Atlantic and Indian Ocean origin enters the Pacific Ocean. 

 The Discovery and Dana observations in the Tasman Sea between 

 Australia and New Zealand, and in the Pacific to the east of New Zealand, 

 show that the salinity of the deep and bottom water has been reduced so 

 much that the maximum values lie between 34.72 and 34.74°/oo. These 

 maximum salinities are found at depths between 2500 and 4000 m, the 

 salinity of the water close to the bottom being slightly lower. From 

 the region where the deep water enters the Pacific Ocean the salinity 

 decreases both toward the north and toward the east. The Discovery 

 data indicate that below the Antarctic Convergence a core of water of 

 salinity higher than 34.72°/oo is found which represents water of the 

 Circumpolar Current, but to the north of this region values below 34.7°/oo 

 prevail, increasing uniformly toward the bottom. The Carnegie and the 

 Dana data similarly show that north of 40°S the highest salinities are 

 found near the bottom, and therefore the structure of the water masses 

 of the Pacific differs completely from that found in the other oceans, 

 where the highest salinities are encountered in the deep water and not 

 in the bottom water. This feature can be explained if one assumes that 

 in the South Pacific Ocean there also exists a circulation which is similar 

 to that of the South Atlantic and Indian Oceans — namely, that inter- 

 mediate and bottom water flow to the north and that a flow of deep water 

 to the south takes place. This north-south circulation is superimposed 

 upon a general flow from west to east. The Pacific Deep Water is, 

 therefore, of Atlantic and Indian origin, but has become so much diluted 



