Pacific Ocean Circulation — Hid AKA 
189 
of equation (24) will be, when the depth h increases indefinitely, 
y, z ) 
1 f 
2D / 
V 0 
fa (x, y; v) cos 
(jk v ) dl - 
It may be mentioned that 7) is a parameter increasing from 0 to °° . 
(29) 
APPLICATION TO THE PACIFIC OCEAN 
In 1950, Munk used the rectangular co-ordinates in discussing the wind-driven oceanic 
circulation in a rectangular ocean. Though he did not take the sphericity of the earth 
into consideration, he could explain the general pattern of the actual circulation of the 
Pacific quite well. Further, his result shows little difference from the one above (Hidaka, 
1951), in which the curvature of the surface of the earth is taken into account and spherical 
co-ordinates are used. 
These results show that the Pacific Ocean can be treated approximately as a rectangular 
ocean, provided we consider that the Coriolis parameter 2c o sin 4> varies with y. This is 
a quite natural consequence when we consider the relation <£ = — ? where R is the mean 
R 
radius of the earth, and y is counted zero on the equator. 
For these reasons, we can represent the Pacific approximately as a square ocean bounded 
by x = 0, x = a, and y — in which y = 0 coincides with the equator (Figure 1). 
Here a is a mean east-west extent of this ocean and approximately equals 120° of longitude 
or 2t/3 in radians. This means that the northern and southern boundaries of this ocean 
2ttR 
are 
given by y = 
or the parallels of 60° N and S. 
To solve equation (28), assume 
ii(x, y, n) = IZ M m (y) N m (x; y), 
(30) 
where m = 1, 2, 3, . . . and N m (x, rj) are functions of x which are to be determined later, 
while M m (y) are of the forms: 
,, / x Try miry 
M.(y) = cos- cos 
iry . miry 
cos — sin — — 
la la 
for m: odd 
for m: even. 
(31) 
Since these functions and their y-derivatives vanish along y = (30) and its y-deriva- 
tives will also vanish along y = This makes the function \f/ (x, y, z) satisfy the con- 
dition (22) along the northern and southern boundaries y = =±=^. 
Stresses of Winds over the Pacific Ocean 
Dr. Munk kindly furnished me with his unpublished data of the distribution of the 
wind stresses over the Pacific Ocean north of 5° S. From these data, the most probable 
