^B r^ORTH PACIFIC CENTRAL VMTER | | CALIFORNIA CURHENT EXT. 



L . I :;oRTH rm:ific equatorial water ^^ north pacific current 



10* N. 



latitude 



Hawaiian Islands, one must take into account the climate 

 and weather of areas thousands of miles away. The face of 

 the earth is essentially a single ocean interrupted by islands 

 that range in size from a single lonely volcanic peak thrust- 

 ing up from the floor of the deep sea to the vast bulk of 

 Eurasia. This ocean occupies more than 70 percent of the 

 surface of the earth. For many reasons, however, the chief 



FIGIKE 2:<. Saliiiilv valut-^ along long. 148 \i . in Mav 

 and Oclobrr 1964. Thr .-rclions rxtrnd to a depth of 500 

 nielors, about 1,500 frot. The shading delineates bodies of 

 Hater whose salinities are eharacterisljc of surfaee values 

 in other parts of the ocean. Note thai at lat. 13° N. there 

 are four layers of waters of different types in the first SOO 

 meters (1.000 feet). 



being that each occupies an identifiable basin and thus forms 

 a convenient unit of study, it is conventional to regard this 

 world ocean as being comprised of four smaller oceans, the 

 Pacific, the Atlantic, the Indian, and the Arctic. The.se 

 bodies are still very large entities; the Pacific Ocean alone 

 occupies about one-third the surface of the earth. 



A Pacific-wide Study 

 Although conditions within one part of the Pacific influ- 

 ence those in all others to some degree, studies of the Pacific 

 Ocean in its enormous entirety are relatively rare. At least 

 two reasons account for this circumstance. The first is that 

 .some studies can be made in a relatively small region with 

 acceptable precision even if one neglects the influence of the 

 remainder of the ocean. The second reason is simply that it 

 is a tremendous task to study the ocean as a whole. Ocea- 

 nographic research has been conducted in the world ocean 

 for almost a century now. An immense fund of information 

 has been collected, particularly within the past few decades. 

 Until the development of computers, it was impossible 

 to handle these data without undue expenditures of money 

 and time. Today analysis of all temperature and salinity 

 data now available from the Pacific Ocean by manual 

 methods would run to some 200 man-years and an expend- 

 iture of $1.5 million. 



FIGURE 24. Surface origin of water types shown in figure 

 23. By sampling the water column near Hawaii, oceanog. 

 raphers ran see the results of events that have happeneil 

 hundreds or even thousands of miles awav. 



34 



