WATER MASSES AND CURRENTS OF THE OCEANS 



199 



The northern branch of the Kuroshio Extension becomes rapidly 

 mixed with the cold waters of the Oyashio, which flow south close to the 

 northeastern coasts of Japan, reaching nearly to 35°N. The extensive 

 work of Japanese oceanographers shows that along the boundary between 

 the Kuroshio Extension and the Oyashio numerous eddies develop within 

 which a thorough mixing of the water masses takes place. From the 

 sections in fig. 53, it is evident that to the north of lat. 36°N the Kuroshio 



Fig. 53. Distribution of temperatures and salinities in a vertical section between 

 lat. 30°28'N, long. 150°04'E, and lat. 42°40'N and long. 157°00'E (after Uda). 



waters, which can be traced to lat. 41°N, have been greatly diluted by 

 the Oyashio water. By these processes of mixing a water mass is 

 gradually being formed which is present in the northwestern Pacific 

 Ocean and which has been called the Subarctic Water of the North 

 Pacific (fig. 40, p. 158). 



These sections bring out the feature that to the north of lat. 36°N 

 intermediate water of a salinity as low as 33.8°/oo is found at a depth of 

 300 m or less. This water, which contains a considerable amount of 

 oxygen, has probably been formed in winter at the convergence between 

 the Kuroshio Extension and the Oyashio, and has sunk from the surface 

 in a manner similar to the sinking of the Antarctic Intermediate Water. 

 From the region of sinking, this intermediate water flows toward the east 

 and spreads over the greater part of the North Pacific. To the south of 

 lat. 36°N intermediate water of salinity between 34.0°/oo and 34.1°/oo is 

 present at a depth of about 800 m, but this water represents the most 

 northern extension of the intermediate water that flows north along the 

 coast of Japan and turns around as part of the big whirl on the right-hand 

 side of the Kuroshio. 



The North Pacific Current. This term is applied to the general 

 eastward flow of warm water to the east of long. 160°E. Details of this 

 flow are not known, but from the Bushnell section of 1934, from the 

 Aleutian to the Hawaiian Islands, it is evident that Kuroshio water 



