Smith 



20' 



19° 



18° 



CURRENTS AT 505 FEET 

 REFERENCED TO 750 FEET 



159° 



158' 



157' 



156' 



155° 



Fig. 13 - Relative currents at 505 feet associated 

 with 1966 counter-rotating eddies. Solid line is 

 the depth contour of 25° C isotherm. 



The Hawaiian Archipelago lies in a southeast to northwest arc, 

 and presents a nearly solid barrier to any impinging ocean currents. 

 Only two of the four openings in the island barrier have sill depths 

 greater than 1000 fathoms; namely, the Kauai Channel (Kauai-Oahu), 

 1800 fathoms, and the Alenuihaha Channel (Maui-Hawaii), 1100 fath- 

 oms. These deeper openings, to the north and south of the island 

 barrier can pass a large volume of water and probably cause a jet 

 stream effect (similar to that of a jet or wake discharged into a 

 fluid at rest (Rossby, 1936). The remaining openings are Kaiwi 

 Channel (Oahu-Molokai) and Pailolo Channel (Molokai-Maui) with 

 sill depths of 300 fathoms and 40 fathoms, respectively. These shal- 

 low openings, in the middle of the island group, although allowing the 

 passage of some water, in effect act as a quasi-solid barrier to fluid 

 flow. In theory, this effect is similar to stream flow along a lamina 

 (Lamb, 1945) and flow past a barrier in a rotating spherical shell 

 (Long, 1952). Consequently, eddies in the lee of the Hawaiian 

 Islands can be generated in several ways. 



412 



