PROCESSING PROCEDURES 



OCEANOGRAPHIC DATA SUMMARY 



25 



Figure 25— Form 4 with example for "OCEANOGRAPHIC DATA SUMMABY.' 



graphically important time and space variables 

 can be used as one of the coordinates. The 

 construction of horizontal and vertical sections 

 requires proper selection of units and spacing 

 of values to bring out the desired oceanographic 

 variables. Another precaution is to maintain 

 the consistency between graphs and quantities 

 of different types. 



Points on vertical plots are usually required 

 to be small to establish accurate curves. In 

 order to find small points, when connecting 

 them by lines, they are adorned by larger 

 symbols. These symbols may be specific of any 

 given variable; for example, temperature fre- 

 quently is designated by >(, salinity by A, 

 oxygen by O, and <r, by V. 



One means of checking consistency of graphs 

 was brought out in section D. 2 where inter- 

 polated temperature and salinity values are 

 plotted on a T-S curve constructed from 



observed values of the two variables. To be 

 consistent and correct, the interpolated points 

 must fall on the curve as in figure 16. 



Another way to check the construction of 

 vertical curves is by plotting the interpolation 

 values with depth. A smooth curve through 

 these points should also pass through the 

 observed values. 



Horizontal Cliarts 



Horizontal charts are used to show the 

 geograpliical variation in oceanographic quan- 

 tities by contoure of equal values. 



A standard contour interval cannot be 

 established to meet all requirements. In mid- 

 latitudes the open sea temperature sections are 

 usually plotted by whole degrees, salinity by 

 0.5%o, oxygen by 0.5 ml/L, and a, by 0.5 inter- 

 vals. In extreme latitudes, different seasons, 

 and inshore areas these intervals must be 

 modified to bring out the desired features. 



