202 
PACIFIC SCIENCE, Vol. IX, April, 1955 
TABLE 2 
Computed Velocity* of the Kuroshio at Different Depths z = 0, VS D z , D z , 3 / 2 D z , 2 D z , and 3 D z 
Along the 33° N Parallel, Assuming D z = 75 meters 
Distance from west boundary (km.) . . . . 
. . . 0 
25 
50 
75 
100 
125 
150 
175 
200 
225 
250 
275 
Surface velocity (cm/sec) 
. . . 0 
163 
217 
196 
146 
94 
52 
25 
12 
7 
8 
11 
Velocity at z = Vi D z (cm/sec) 
. . . 0 
150 
206 
186 
135 
84 
43 
17 
4 
0 
1 
4 
Velocity at z = D z (cm/sec) 
. . . 0 
138 
188 
167 
120 
72 
32 
7 
-5 
-8 
-6 
-3 
Velocity at z — 3 / 2 D z (cm/sec) 
123 
168 
149 
104 
47 
21 
9 
-12 
-14 
-12 
-8 
Velocity at z = 2 D z (cm/sec) 
. . . 0 
107 
147 
129 
87 
44 
11 
-9 
-22 
-19 
-15 
-11 
Velocity at z = 3 D z (cm/sec) 
. . . 0 
79 
110 
94 
59 
24 
-3 
-25 
-25 
-17 
-18 
-13 
* To get the velocity for values of D z other than 75 m. multiply these velocities by 75/D 2 , where D z is ex- 
pressed in meters. 
The computations were rather tedious and took three computers more than 6 months to 
complete for the surface, }/zD z , D z , %D Z , 2 D z , and 3D Z . The values of a, 13, 7, and 8 , which 
are the roots of the quadratic equations (73) with rj as a parameter and computed for the 
necessary values of are compiled in Tables 5-14. 
The values of the stream-function were computed for the westernmost one-fifth part 
of the entire expanse of the ocean, and the streamlines were drawn for the layers 2 = 0 
(surface), |^D 2 , D z , \D Z , 2 D z , and 3D Z . The computations were not carried out for the 
deeper levels and for the part to the east of this area, partly because we did not have 
enough time to compute, and partly because the central and eastern part are not as 
interesting. We have only a very slow zonal flow in the central part and very diffuse 
meridional flow close to the eastern coast of the ocean. Indeed, the California and Peru 
Currents are considered to be produced by local winds as proved by Munk (1950). 
The circulation patterns in the area close to the western coast were obtained from these 
computations and illustrated in Figures 3a-f. The discussions for them will be given in 
the following paragraphs. 
Table 2 gives the velocities of the western current in the subtropic gyre corresponding 
to the Kuroshio, or the Japan Current, at the depths 2 = 0 (surface), f^D Z} D z , § D z , 
2 D z , and 3D Z along the 33° N parallel which is the swiftest part of this mighty current. 
These velocities were computed by the formula: 
v = ( dA = ^(\o + AX) - 1MA0 - AX) 
VdxAo linear distance of 2AA 
and taking D z — 75 meters. Because the velocity is inversely proportional to the quantity 
D z , we can compute it for any other value of D z . For this we have only to multiply these 
figures by 13/D z where D z is expressed in meters. The maximum surface velocity of 217 
cm/sec agrees with actual observations very closely. 
Table 3 gives the distribution of E-W components along a meridian 24° of longitude 
east of the western boundary, or one fifth 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 z was again assumed to be 75 meters. Discussions concerning 
these results will be made in the following paragraphs. 
Surface Circulation 
The numerical result for the horizontal circulation has been worked out for several 
levels specified by the ratio z/D z . We show here those of the surface (2 = 0), z/D z — 0.5, 
