Isaacs 



Such changes were long thought to be essentially local 

 phenomena, generated by local variations in currents, winds and up- 

 welling. Several workers, however, noted that extreme changes often 

 occurred in the same year in areas as remote as Japan, San Francisco 

 and Peru. This has been called teleconnection . 



The work of the Bureau of Commercial Fisheries in analyzing 

 the sea surface temperature records from surface ships has shown that 

 the anomalies are commonly of very large scale and long persistence. 

 Figures 2 and 3 are examples of such large-scale anomalies. A 

 pattern similar to Figure 2 persisted in the eastern North Pacific 

 for a period of more than eight months in 1958 and that of Figure 3 

 during much of 1957. Hatched areas are colder than normal and clear 

 areas warmer. 



We now believe that teleconnection is an expression of the 

 very large scale of these features, certainly not some mysterious 

 communication across the reaches of the sea between isolated events. 



The sudden change in the conditions of the North Pacific 

 in 1956 to 1959 and which terminated the period of persistence, 

 demonstrated afresh the importance and magnitude of the effects of 

 these variations. One of the deepest and most prolonged meteoro- 

 logical lows on record developed off Washington, remaining for 

 three months. A strong narrow countercurrent developed along the 

 west coast of the United States, carrying subtropical organisms as 

 far north as Oregon, southern fish visited Alaska, the monsoon 

 delayed its onset a full six weeks beyond its appointed time, desert 

 isles of the Central Pacific became clothed with green, the heaviest 

 rains in a decade dampened California, everywhere was a stirring 

 engendered by these events. 



Figure 4 exemplifies a subtropical marine organism carried 

 far north by the narrow countercurrent, and Figure 5, from the 

 records of the California Fish and Game, shows the invasion of 

 tropical fishes into California waters in these times. 



The ocean-air interactions related to these changes are 

 partly understandable in a qualitative way- For example, the onset 

 of the 1956-1959 change is most marked in the region of the Aleutians 

 where warm Central Pacific water was carried far north of its usual 

 position by an unusual wind pattern in the winter of 1956-57 • 

 Namias has shown that the development of the major features of the 

 North Pacific weather can be better hindcast when the persistence 

 from ocean-air interaction is considered. 



The importance of attaining a better understanding of 

 these events is now clear, and an approach to this understanding can 

 be designed. 



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