# gsw_SA_freezing_from_CT

`Absolute Salinity of seawater at the freezing point`

## USAGE:

`SA_freezing = gsw_SA_freezing_from_CT(CT,p,saturation_fraction)`

## DESCRIPTION:

```Calculates the Absolute Salinity of seawater at the freezing temperature.
That is, the output is the Absolute Salinity of seawater, with the
fraction saturation_fraction of dissolved air, that is in equilibrium
with ice at Conservative Temperature CT and pressure p.  If the input
values are such that there is no positive value of Absolute Salinity for
which seawater is frozen, the output, SA_freezing, is put equal to NaN.```
 ```Click for a more detailed description of calculating Absolute Salinity of seawater at the freezing point.```

## INPUT:

```CT  =  Conservative Temperature (ITS-90)                       [ deg C ]
p   =  sea pressure                                             [ dbar ]
( i.e. absolute pressure - 10.1325 dbar )

OPTIONAL:
saturation_fraction = the saturation fraction of dissolved air in
seawater.
( i.e., saturation_fraction must be between 0 and 1, and the default
is 0, air free )```
```p & saturation_fraction (if provided) may have dimensions 1x1 or Mx1 or
1xN or MxN, where CT is MxN.```

## OUTPUT:

```SA_freezing  =  Absolute Salinity of seawater when it freezes, for
given input values of Conservative Temperature
pressure and air saturation fraction.            [ g/kg ]```

## EXAMPLE:

```CT = [-0.11901; -0.15608;  -0.72138; -1.97738;  -2.31728;  -2.56764;]
p =  [     10;      50;     125;     250;     600;    1000;]
saturation_fraction = 1```
`SA_freezing = gsw_SA_freezing_from_CT(CT,p,saturation_fraction)`
`SA_freezing =`
```   2.280500648179144
2.416867651098550
11.973503162175106
32.868973869711390
34.017513292374431
32.859871943514150```

## AUTHOR:

`Trevor McDougall and Paul Barker   [ help@teos-10.org ]`

## VERSION NUMBER:

`3.05 (16th February, 2015)`

## REFERENCES:

```IOC, SCOR and IAPSO, 2010: The international thermodynamic equation of
seawater - 2010: Calculation and use of thermodynamic properties.
Intergovernmental Oceanographic Commission, Manuals and Guides No. 56,
UNESCO (English), 196 pp.  Available from the TEOS-10 web site.
See section 3.3 of this TEOS-10 Manual.```
```McDougall, T.J., P.M. Barker, R. Feistel and B.K. Galton-Fenzi, 2014:
Melting of Ice and Sea Ice into Seawater and Frazil Ice Formation.
Journal of Physical Oceanography, 44, 1751-1775.```
`The software is available from http://www.TEOS-10.org`