User`s manual

Appendix IV: Derived Parameter Formulas

For formulas for the calculation of conductivity, temperature, and pressure, see

the calibration sheets for your instrument.

Formulas for the computation of salinity, density, potential temperature,

specific volume anomaly, and sound velocity were obtained from "Algorithms

for computation of fundamental properties of seawater", by N.P. Fofonoff and

R.C Millard Jr.; Unesco technical papers in marine science #44, 1983.

• Temperature used for calculating derived variables is IPTS-68.

Following the recommendation of JPOTS, T

is assumed to be

1.00024 * T

(-2 to 35 °C).

Equations are provided for the following oceanographic parameters:

• density (density, sigma-theta, sigma-1, sigma-2, sigma-4, sigma-t)

• thermosteric anomaly

• specific volume

• specific volume anomaly

• geopotential anomaly

• dynamic meters

• depth (salt water, fresh water)

• salinity

• sound velocity (Chen-Millero, DelGrosso, Wilson)

• average sound velocity

• potential temperature (reference pressure = 0.0 decibars)

• potential temperature anomaly

• specific conductivity

• derivative variables (descent rate and acceleration) - if input file has not

been averaged into pressure or depth bins

• oxygen (if input file contains pressure, temperature, and either

conductivity or salinity, and has not been averaged into pressure or

depth bins) - also requires oxygen current and oxygen temperature

(for SBE 13 or 23) or oxygen signal (for SBE 43)

• corrected irradiance (CPAR)

Note:

Algorithms used for calculation of

derived parameters in SEASAVE

and in SBE Data Processing’s

Data Conversion, Derive, and

SeacalcW modules are identical,

except as noted.