coast. Eddies off the coast of Washington were 

 such that the northward flow over the Con- 

 tinental Slope, perhaps the Davidson Current, 

 did not appear to continue north of lat. 48° N. 



Geostrophic currents, 200/1,500 db., fol- 

 lowed the same direction as the surface cur- 

 rents, and showed maxima of subsurface 

 velocity in the eddies off the Washington coast. 



The net volume transport, based on a 1,500 

 db. reference level, was 3 x lO^m.Vsec. north- 

 ward past Cape Cook during both spring and 

 fall. A shoreward component of total transport 

 6.7 X 10"m.^/sec., was present in the spring, 

 but by fall the transport had reversed to the 

 seaward at 0.4 x lO-'m.Vsec. Northward trans- 

 port of 4 to 5 X lO^m.Vsec. occurred locally off 

 the coast of Washington, but was associated 

 with strong anticyclonic eddies which had 

 nearly an equivalent southward transport. 

 Although the existence of the California Un- 

 dercurrent may be implied by the distribution 

 of properties and supported by the direction of 

 the geostrophic currents at 200 m., the Current 

 did not appear to contribute more than 1 x 

 lO^m.^/sec. to the net northward flow along 

 the coast of Washington. 



The most striking and permanent feature of 

 the distribution of properties within the area 

 was the surface salinity front which extended 

 to a maximum distance of 112 km. seaward 

 from the coast of Washington during the 

 spring, but was confined within 64 km. of the 

 coast in the fall. Vertical sections normal to 

 the shore showed that the major structural 

 features of salinity, temperature, and dissolved 

 oxygen were consistent along each of the nine 

 lines. The distribution of properties varied 

 considerably above 200 m. within the main 

 halocline, thermocline, and oxycline. Below 200 

 m. the range of values of salinity, temperature, 

 and dissolved oxygen at a given depth was 

 comparatively small. The major feature below 

 the halocline was the nearly horizontal isolines 

 of temperature, salinity, and dissolved oxygen 

 along each vertical section. The concentration 

 of dissolved oxygen had a pronounced mini- 

 mum at about 900 m. throughout the study 

 area. Minor variations at 200 m. in the fall 

 indicated that a ridge of high-salinity water, 

 also associated with high temperature and low 



dissolved oxygen, was especially well developed 

 along the Continental Slope of Washington. 



Samples obtained near the bottom confirmed 

 the absence of any significant change in the 

 salinity, temperature, or dissolved oxygen at a 

 particular depth along the Continental Slope 

 between the Columbia River and Cape Cook. 

 Thus, the only significant variations in water 

 properties occur in the upper 200 m. 



The T-S curves indicated that a water mass 

 of high salinity and high temperature was 

 present over the Continental Slope. Off the coast 

 of Washington the boundary between water 

 masses of slightly different characteristics was 

 distinct below 400 m. between 165 and 220 km. 

 from shore. The more southern water mass 

 near shore occupied a greater portion of the 

 coastal area during the fall than in the spring. 

 Although this implied an increase in north- 

 ward flow at depth, the California Undercur- 

 rent, increased flow was not reflected in the 

 net volume transport. 



LITERATURE CITED 



Bennett, E. B. 



1959. Some oceanographie features of the north- 

 east Pacific Ocean during August 1955. J. Fish. 

 Res. Bd. Can. 16(5): 565-633. 

 BuDiNGER, Thomas F., Lawrence K. Coachman, and 

 Clifford A. Barnes. 



1964. Columbia River effluent in the northeast 

 Pacific Ocean, 1961, 1962: selected aspects of 

 physical oceanography. Dep. Oceanogr. Univ., 

 Wash., Seattle, Tech. Rep. No. 99, 78 pp. 

 Burt, Wayne V., and Bruce Wyatt. 



1964. Drift bottle observations of the Davidson 

 Current off Oregon. In Studies on Oceanog- 

 raphy, Tokyo, Dedicated to Prof. Hidaka: 156- 

 165. Univ. Wash. Press, Seattle, Wash. 

 Cromwell, Townsend, and Joseph L. Reid, Jr. 



1956. A study of oceanic fronts. Tellus 8(1): 

 94-101. 

 DoDiMEAD, A. J., F. Favorite, and T. Hirano. 



1963. Salmon of the North Pacific Ocean, Part 

 II, Review of the oceanography of the Subarctic 

 Pacific Region. Int. N. Pac. Fish. Comm., Bull. 

 13, 195 pp. 

 Doe, L. a. E. 



1955. Offshore waters of the Canadian Pacific 

 Coast. J. Fish. Res. Bd. Can. 12(1): 1-34. 

 Favorite, Felix. 



1961. Surface temperature and salinity off the 

 Washington and British Columbia coasts, Au- 



GEOSTROPHIC CIRCULATION 



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