542 EIGHTH PACIFIC SCIENCE CONGRESS 



and taking D.^ — 75 meters. Because the velocity is inversely propor- 

 tional to the quantity D^, we can compute it for any other value of D,. 

 For this we have only to multiply these figures by IbjDj^ where D^ is 

 expressed in meters. The maximum surface velocity of 217 cm /sec 

 agrees with actual observations very closely. 



Table III gives the distribution of EW-components along a meridian 

 24° of longitude east of the western boundary, or 1/5 of the entire 

 east-west expanse of the Pacific Ocean off the western coast. At this 

 distance from the western coast the coastal effect nearly vanishes and 

 the pattern of the circulation consists of approximately zonal flows. 

 In this table the value of D^ was again assumed. to be 75 meters. Dis- 

 cussions concerning these results will be made in the following para- 

 graphs. 



II. Surface Circulation 



The numerical result for the horizontal circulation has been v/orked 

 out for several levels specified by the ratio zjD^. We show here those 

 of the surface (z = 0), z/D, = 0.5, zjD, = 1, z/D, = 1.5, z/D, = 2 

 and z/Z)^ = 3. The most important of them is, of course, the surface 

 circulation, and Figure 3 shows its pattern. The gross features of the 

 current distribution on the surface thus do not seem to differ much from 

 those given by Munk (1950) and by the author (1951) for the distribu- 

 tion of mass transport streamlines. Because of the considerable labor 

 contained in the calculation, the computation is confined only to the 

 western part of the ocean bounded by two meridians A = and A = 0.2, 

 that is, 24° of longitude apart. Choice of the western part of the ocean 

 for the computation was made because the circulation patterns in that 

 section are more complicated and hence more interesting. In the cen- 

 tral part of the ocean we will have indeed a very slow motion approxi- 

 mately in east-west direction, while very diffuse meridional motion will 

 exist close to the eastern coast. 



We have a number of gyres in the surface circulation corresponding 

 to those obtained in Munk's (1950) and the author's (1951) results with 

 respect to mass transport. We have a broad gyre with strong western 

 current flowing north in the latitudes between 20° and 40° N and 

 corresponding to the Kuroshio or Japan Current. We also notice one 

 boundary vortex, but the secondary boundary vortex is not distinct. 

 We have a subtropic gyre with the western current flowing south. This 

 coiTCsponds to the Mindanao Current. Of course, we have a faint sub- 

 arctic gyre corresponding to the Oyashio or the Kurile Current. 



On the surface of the Southern Pacific Ocean, we have western 

 currents flowing north a little south of the equator and in the sub- 

 antarctic latitudes. Between these two we have a strong current cor- 



