R: Seawater salinity from temperature and density

swSTrho {oce} | R Documentation

## Seawater salinity from temperature and density

### Description

Compute Practical or Absolute Salinity, given in-situ or Conservative Temperature, density, and pressure. This is mainly used to draw isopycnal lines on TS diagrams, hence the dual meanings for salinity and temperature, depending on the value of `eos`.

### Usage

    swSTrho(temperature, density, pressure, eos = getOption("oceEOS", default =
      "gsw"))

### Arguments

`temperature` | in-situ temperature [degC], defined on the ITS-90 scale; see “Temperature units” in the documentation for `swRho`.
`density` | in-situ density or sigma value [kg/m^3]
`pressure` | in-situ pressure [dbar]
`eos` | equation of state, either `"unesco"` [1,2] or `"gsw"` [3,4].

### Details

For `eos="unesco"`, finds the practical salinity that yields the given density, with the given in-situ temperature and pressure. The method is a bisection search with a salinity tolerance of 0.001. For `eos="gsw"`, the function `gsw_SA_from_rho` in the `gsw` package is used to infer Absolute Salinity from Conservative Temperature.

### Value

Practical Salinity, if `eos="unesco"`, or Absolute Salinity, if `eos="gsw"`.

### Author(s)

Dan Kelley

### References

1. Fofonoff, P. and R. C. Millard Jr, 1983. Algorithms for computation of fundamental properties of seawater. Unesco Technical Papers in Marine Science, 44, 53 pp

2. Gill, A.E., 1982. Atmosphere-ocean Dynamics, Academic Press, New York, 662 pp.

3. IOC, SCOR, and IAPSO (2010). The international thermodynamic equation of seawater-2010: Calculation and use of thermodynamic properties. Technical Report 56, Intergovernmental Oceanographic Commission, Manuals and Guide.

4. McDougall, T.J. and P.M. Barker, 2011: Getting started with TEOS-10 and the Gibbs Seawater (GSW) Oceanographic Toolbox, 28pp., SCOR/IAPSO WG127, ISBN 978-0-646-55621-5.

### See Also

`swTSrho`

Other functions that calculate seawater properties: `T68fromT90`, `T90fromT48`, `T90fromT68`, `swAbsoluteSalinity`, `swAlphaOverBeta`, `swAlpha`, `swBeta`, `swCSTp`, `swConservativeTemperature`, `swDepth`, `swDynamicHeight`, `swLapseRate`, `swN2`, `swPressure`, `swRho`, `swRrho`, `swSCTp`, `swSigma0`, `swSigma1`, `swSigma2`, `swSigma3`, `swSigma4`, `swSigmaTheta`, `swSigmaT`, `swSigma`, `swSoundAbsorption`, `swSoundSpeed`, `swSpecificHeat`, `swSpice`, `swTFreeze`, `swTSrho`, `swThermalConductivity`, `swTheta`, `swViscosity`, `swZ`

### Examples

    swSTrho(10, 22, 0, eos="gsw") # 28.76285
    swSTrho(10, 22, 0, eos="unesco") # 28.651625

[Package oce version 0.9-20 Index]