CIRCULATION NEAR THE WASHINGTON COAST 587 



outflow of the Strait of Juan de Fuca near the mouth of the Strait. 

 Similar conclusions as to the seasonal shift in currents were reached by 

 Thompson and Van Cleve (1936) from drift bottle experiments com- 

 menced about 80 miles off the Canadian Coast. These authors also 

 relate the change in direction of flow during the summer to a change 

 in wind pattern. Some dynamic sections along the coasts of Washing- 

 ton and Oregon are presented by Sands (1937), but these are too few 

 in number and too close to shore to correlate with the present work. 



Farther offshore, the circulation off the Canadian Coast has been 

 studied by Doe (1952) and Goodman and Thompson (1940) in two 

 sections, from the Strait of Juan de Fuca to Dutch Harbor, and from the 

 Strait of Juan de Fuca to Hawaii. Still farther offshore, the Carnegie 

 Cruise VII (Fleming, 1945) established the gi-oss structure of the east- 

 ward flowing Aleutian Current and the beginning of its separation into 

 southeasterly and northeasterly branches. Two or more sections have 

 also been made by Scripps Institution of Oceanography, the U. S, Fish 

 and Wildlife Service, and the U. S. Navy Electronics Laboratory, but 

 the results are unpublished. To the south, Scripps Institution of Ocea- 

 nography have studied the coastal currents very intensively and their 

 cruises have occasionally come as far north as the Columbia River. 

 Thus the details of the circulation near the Washington Coast are little 

 knoM^n. 



With respect to the G.E.K., as used in areas of weak and poorly 

 defined currents such as this, there is little published. The interpreta- 

 tion of the results as currents is in some question, as is the "K" factor. 

 The apparently rotary ciUTent changes observed, although indicated by 

 von Arx (1950), have not been carefully analyzed, probably because in 

 areas of high currents they are relatively less important. Oceanogra- 

 phers at Scripps Institution of Oceanography are known to be working on 

 this problem. For analysis of the rotary current changes in the deep 

 sea, one must turn to the direct measurements made from anchored 

 vessels, the BLAKE in West Indian waters (Pillsbury, 1891), the 

 MICHAEL SARS (Helland-Hansen, 1930), the METEOR (Defant, 1932). 

 the ALTAIR (Defant, 1940), and the ARMAUER HANSEN (Ekman, 

 1953). In all of these, the uncertainties due to the motion of the an- 

 chored vessels weaken the validity of the conclusions. However, rotary 

 current changes do occur and these changes apparently contain com- 

 ponents of tidal and inertial periods as well as random fluctuations. 

 The existence of rotary currents of tidal period in shallower water is 

 v.ell established, and Gustafson and Kullenberg (1936) have demon- 

 strated an excellent example of inertial rotations in the Baltic. 



