Ocean Temperatures along the West Coast of North America. 249 



The bulk of the Kuro Siwo trends eastward, but perhaps nowhere 

 washes the shores of the United States, being separated from them by 

 the narrow cold stream, and yet is near enough to exercise a powerful 

 influence on the coast climate. Both streams flow to the south and 

 produce a narrow eddy current next to the shore flowing north. 



The directions of the observed currents can, according to Richter, 

 be accounted for on the basis of Zoppritz's theory from the fact that 

 the coast of the United States tends northeastward 1 ) from Cape Men- 

 docino, latitude 40 to Tatoosh Island, latitude 49, and tends south- 

 eastward to San Diego, latitude 32 45', while the prevailing winds 

 are easterly near Tatoosh Island and westerly near San Diego. 



3. Bishop (6) assumed a flow of cold antarctic water northward 

 along the ocean bottom, and explained how it would cool the in- 

 shore water as follows. It has been the custom to call the cold 

 stream which is of a very low temperature, immense volume, and great 

 velocity, and flows along the west coast of North America, a con- 

 tinuation of the Japan Current, but there are two insuperable objec- 

 tions to that solution. First, the Japan Current must necessarily pass 

 out and dissipate itself in the vast breadth of the Pacific Ocean long 

 before reaching Alaska. Second, the Japan Current is entirely too 

 warm, and the Alaskan glaciers are inadequate to materially cool the 

 adjacent waters; 



But the antarctic continental glacier extending 4000 miles in length 

 along the antarctic circle cools the ocean water, and because of its 

 increased density this cold water sinks to the bottom and flows north- 

 ward, being forced on by the accumulated supply behind it. After 

 passing the Tropic of Cancer, the Pacific Ocean contracts in breadth. 

 In latitude 45, it is only half as wide as at the equator. Hence, 

 the northward moving water is accelerated to twice its previous velocity. 

 From the rotation of the earth this current would be forced to the 

 east against the North American continent in the latitude of Sitka and 

 Vancouver's Island. The resulting pressure drives .the water up the 

 continental slope and it then flows southward, having no other outlet. 

 It continues along the coast, being held there in opposition to the west- 

 ward deflecting force due to the earth's rotation by the eastward 

 pressure due to the bottom current which continually pushes up from 

 the deep sea under the easterly globe-thrust along the entire west coast 

 of North America. 



*) The coast actually trends slightly to the west. 



Revue d. ges. Hydrobiol. u.Hydrogr. Bd. V. H. 2/3. 17 



