SOUTH PACIFIC 



91 



northern New Zealand and as far as about latitude 20° S. in the mid- 

 longitudinal belt of the ocean. 



It is much to be regretted that the data are not sufficient to extend 

 the July-August survey farther southward for the mid-Pacific. Con- 

 ditions, however, along the Chilean coast (table 24) suggest that seas 

 higher than 8 feet are to be expected during at least 40 percent of the 

 time, during these months, to the southward of the latitude of the 

 Straits of Magellan, generally. 



Table 24. 



-Average percentage frequencies of high seas and swells within approxi- 

 mately 300 miles of the west coast of South America 



The seasonal character of the weather also makes it likely that the 

 waves of 20 feet and higher, that have been reported 15 percent of the 

 time for the year as a whole (table 8, p. 21) in mid-Pacific in the 

 latitude of southern Chile, actually develop there rather more often 

 during the northern summer than during the northern winter. 



Other aspects of the South Pacific sea pattern of northern summer 

 deserving attention are that high seas running out from the coasts of 

 Peru and of northern Chile are increasingly frequent, as the average 

 strength of the Southeast Trades increases out from the land, and 

 that the sea is high less often between Australia and the North Island 

 of New Zealand than it is eastward from the latter. 



The most interesting aspect of the South Pacific swells of northern 

 summer is that these have been reported "high" considerably more 

 often than the sea has throughout the region of the Southeast Trades, 

 as illustrated by the fact that the average frequency for this category 

 between the equator and latitude 20° S., in July and August, is about 

 13 percent for swells, but only about 5 percent for seas, with the con- 

 trast in this respect between the two classes of waves nearly as wide 

 close in to the South American coast as it is out in midocean. "Rolling 

 down the Trades," an old expression from sailing-ship days, is thus 

 much more than a figure of speech when applied to the South Pacific 

 Trades in northern summer. 



The fact that the northern summer swell runs high northeastward 

 from New Zealand on the one side (45 to 91 percent), as well as along 

 South America at corresponding latitudes on the other (20 to 42 per- 



