North Pacific Ocean 

 Oyashio (Kamchatka) 



The Oyashio originates from the main part of the Anadyr Current 

 south of Cape Olyutorski at about 59°N. on the Siberian side of the 

 Bering Sea. It sets westward from this region and has an average width 

 of about 135 miles j the mean speed is about O.3 knot dioring summer and 

 0.5 knot during autumn. In the vicinity of 58"^.^ l65°E. the current 

 narrows and turns southward along the coast; the current is 30 to ^0 

 miles wide to about 56°W.j widens from about kO to 50 miles as far as 

 53°N., and averages 0.6 knot. From 53°N. to the southern tip of 

 Kamchatka Peninsula the mean speed increases to about O.9 knot. 



South of 56°N. the Oyashio is very stable throughout the year^ and 

 the only variation is in the slightly higher speeds during winter. Table 

 6 is derived from 502 surface observations and shows the persistency of 

 the Oyashio south of 56°W. and east of lkj°'E. The total percent 

 frequency in the prevailing south through west quadrant will exceed 

 60 percent, with maximum speeds reaching 3 knots • Some of the north- , 

 northeast-j and east-setting observations may be partly the result of 

 tidal currents that predominate in the nearshore regions of the Kuril 

 Islands; the remainder of these observations most likely result from 

 the effect of opposing winds upon the weaker flows along the edges of 

 the Oyashio^ since the area containing the surface observations slightly 

 overlaps the boundaries of the current. 



The Oyashio continues southwestward past the Kurils to a region 

 off the southeast coast of Hokkaido. Here^ it is influenced by a 

 branch of che Tsushima Current, which sets from Tsugaru Strait and 



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