PART I 



TABLE FOR DETERMINING DENSITY OF SEA WATER 



BACKGROUND AND PURPOSE 



The determination of density (o- ) from observed temperature and 

 salinity values has been done by using slide rules, nomograms, and 

 tables. Both the slide rule and nomograms require frequent use on 

 the part of the operator to develop and retain proficiency. Recent 

 tables for determining sea water density eliminate much of the laborious 

 interpolation required by earlier tables and provide a high degree 

 of accuracy. However, interpolation tables must be used to obtain 

 cr values equivalent to the decimal portion of given salinities (for 

 salinity increments of 0.01%o). Such interpolations require additional 

 entries in the tables to obtain the desired density value. 



The density table in this publication requires but one entry at 

 the given temperature to make the necessary computation. Computed 

 values of a may have an error of 2 units in the second decimal place, 

 which is permissible for many applications. Sigma-t values of the 

 above order of accuracy can be computed rapidly without subjection to 

 possible reading errors encountered in numerous entries. 



ARRANGEMENT 



The table for determining density of sea water presents values 

 of (T corresponding to temperatures from -2.00°C to 29.99°C and 

 salinities from 10.00%o to 39.99%&. The table is arranged in three parts by 

 salinity intervals of 10.00%(;. For a given temperature in column 

 one the corresponding a value, for the base of the salinity interval 

 entered, is indicated in column two. As the salinity increases the 

 (T value increases by an amount equal to the factor, f, in column 

 three multiplied by the last three digits of the given salinity (observing 

 decinnal places). Temperature values are provided in column one for 

 every hundredth (.01) increnaent in the cr value in column two. Where 

 the given temperature is intermediate between the values provided, 

 the lower value is used. 



EXAMPLE OF COMPUTATION 



Given a temperature of 15.70°C and a salinity of 36.47%o compute 

 the cr value. 



