248 
PACIFIC SCIENCE, Vol. IV, July, 1950 
Fig. 25. Average depth of the virtually isothermal layer (1941—1947). 
Fig. 26. Diurnal sea temperature variation 
(° F.) ; 21°-34° N, 138°-157° W. 
NO. OF OBSERVATIONS 
SFC. 50 94 7® 45 41 48 ®9 61 ©ft «3 41 3® 
100' 50 ®9 75 44 48 41 58 61 83 ©I 3® 35 
200' 39 51 57 25 29 29 4® 48 4 4 39 29 24 
300' 33 45 47 21 ZB 2© 39 3® 38 21 19 20 
400' IS 25 25 6 14 I® 18 17 14 15 10 12. 
Fig. 27. Annual variation of temperature. 20°— 
25° N, 157°-160° W. 
