R: Salinity from electrical conductivity, temperature and...

swSCTp {oce} | R Documentation

## Salinity from electrical conductivity, temperature and pressure

### Description

Compute salinity based on electrical conductivity, temperature, and pressure.

### Usage

    swSCTp(conductivity, temperature = NULL, pressure = NULL,
      conductivityUnit, eos = getOption("oceEOS", default = "gsw"))

### Arguments

`conductivity` | a measure of conductivity (see also `conductivityUnit`) or an `oce` object holding hydrographic information. In the second case, all the other arguments to `swSCTp` are ignored.
`temperature` | in-situ temperature [degC], defined on the ITS-90 scale; see “Temperature units” in the documentation for `swRho`.
`pressure` | pressure [dbar]
`conductivityUnit` | string indicating the unit used for conductivity. This may be `"ratio"` or `""` (meaning conductivity ratio), `"mS/cm"` or `"S/m"`. Note that the ratio mode assumes that measured conductivity has been divided by the standard conductivity of 4.2914 S/m.
`eos` | equation of state, either `"unesco"` or `"gsw"`.

### Details

Calculate salinity from what is actually measured by a CTD, i.e. conductivity, in-situ temperature and pressure. Often this is done by the CTD processing software, but sometimes it is helpful to do this directly, e.g. when there is a concern about mismatches in sensor response times. If `eos="unesco"` then salinity is calculated using the UNESCO algorithm described by Fofonoff and Millard (1983); if it is `"gsw"` then the Gibbs-SeaWater formulation is used, via `gsw_SP_from_C`.

### Value

Practical salinity.

### Author(s)

Dan Kelley

### References

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

### See Also

For thermal (as opposed to electrical) conductivity, see `swThermalConductivity`. For computation of electrical conductivity from salinity, see `swCSTp`.

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

### Examples

    swSCTp(1, T90fromT68(15), 0, eos="unesco") # 35
    swSCTp(1, T90fromT68(15), 0, eos="gsw")    # 35

[Package oce version 1.0-1 Index]