REPORT ON OCEANOGRAPHY 37 



plankton per cubic meter of water varied from 0.01 to 55 cc. while the 

 zooplankton volumes averaged between 0.5 and 1 cc. A prehminary 

 examination of the individual samples indicates definite species differ- 

 ences with depth, position in an inlet, and from inlet to inlet, and an 

 attempt is being made to correlate the distribution with temperature 

 and salinity. The most abundant groups were Copepoda and Clado- 

 cera, which often occurred in complementary proportions. The former 

 were more abundant in the deeper (and usually more saline) water, 

 whereas the latter were more common in the upper layer of less saline 

 water. The Cladocera were often the only zooplankton present in the 

 upper, brackish water. 



Future Policy. 



The immediate aim of the Institute's field observation programme is 

 to obtain more detailed information about the current distributions, 

 both in depth and transversely, with the object of separating the tidal 

 and estuarial components. Further observations of the mid-depth in- 

 ternal waves are planned in order to determine their frequency and 

 whether they are progressive or stationary. 



A study of the plankton populations is also being made in order 

 to determine if there are any correlations with the circulation. 



Cameron (1951) has demonstrated the relationship between the 

 mass and velocity distributions in a deep inlet. He has introduced into 

 the equations of motion in a two-dimensional tideless mathematical 

 model, and analytical expression of the presumed transport and derived 

 a mass field which is similar to that observed in typical B.C. inlets. 



He has presumed eddy frictional force proportional to the vertical 

 gradual of shear, and retaining the vertical terms, has indicated the 

 existence of a critical transport in the steady state. The soleaoidal field 

 resulting from the fresh water distribution is sufficient to maintain 

 a steady state of field acceleration and balance frictional forces similar 

 in magnitude to those derived by Jacobsen. 



He is continuing his investigation into the possible effect of tides 

 in such an inlet. There is evidence to suggest that their dynamics may 

 contribute to the maintenance of an average baroclinic field and that 

 the present concept of the role of eddy forces may be exaggerated. 



The Institute has supervised the analysis of hydrographic and 

 oceanographic data obtained in the southeastern Beaufort Sea in 1951 

 and 1952. Cameron has reported (1951, 1952) that the influence of 

 the MacKenzie river on the circulation of the contiguous inshore wa- 

 ters is predominately to the east of the MacKenzie delta. He has demon- 

 strated the important effect of winds on the distribution of the fresh- 

 water discharged by the river. 



