CHAPTER 8 



41° 



E 

 _o 



Z 



o 



< 



> 

 LU 

 _J 

 UJ 



LU 



o 

 < 



z> 



40° 



39° 



75° 



74° 73° 72° 



FIGURE 8-7.— Solution of model for i. surface elevation (cm). May 18-23, 1976. 



71" 



were available to find values of D.O. for regions outside 

 the boundaries, these were approximated by vertically 

 averaging D.O. at stations on the outside boundaries. 

 Oxygen concentration data were not available for 

 XWCC-10 at the northeastern and southern boundaries 

 of the region. To compute the volume-averaged concen- 

 trations for XWCC-10, all data available in each segment 

 were utilized. The boundary concentrations for XWCC-10 

 were calculated by using the same ratio between the 

 boundary and adjacent segment concentrations as was 

 observed on XWCC-9. 



Oxygen fluxes were found for each segment boundary 

 during the four separate intervals. The oxygen fluxes were 

 calculated by multiplying the water flux through each seg- 

 ment boundary (fig. 8-11) by the oxygen being trans- 

 ported. The oxygen concentrations were different for each 

 interval because they were linearly interpolated in time 

 between the values for XWCC-9 and XWCC-10 (table 

 8-1) fluxes. The oxygen fluxes at each boundary were then 



averaged, in a manner similar to the water fluxes, to pro- 

 duce an average over the entire 42-day interval (fig. 8-12). 

 The first two terms in eq. (4) were calculated for each 

 segment from the volume of the segment and the time 

 rate of change on D.O. between XWCC-9 and XWCC-10 

 (table 8-1) and the divergence of the oxygen fluxes from 

 the values in figure 8-12. The net utilization rate was 

 calculated using eq. (4). Values of all terms in eq. (4) are 

 listed in table 8-2. The residual term, 5, is a net utilization 

 rate incorporating all sources of oxygen other than ad- 

 vective fluxes, such as phytoplankton production and ver- 

 tical diffusion, minus any utilization of oxygen, such as 

 respiration of any ogranism and bacterial decay. 



DISCUSSION 



Use of the diagnostic model is limited both in concept 

 and input data to representation of circulation patterns 



179 



