# gsw_melting_seaice_into_seawater

    the resulting SA and CT when seaice is melted
    into seawater

## Contents

- USAGE:
- DESCRIPTION:
- INPUT:
- OUTPUT:
- EXAMPLE:
- AUTHOR:
- VERSION NUMBER:
- REFERENCES:

## USAGE:

    [SA_final, CT_final] = ...
     gsw_melting_seaice_into_seawater(SA,CT,p,w_seaice,SA_seaice,t_seaice)

## DESCRIPTION:

    Calculates the Absolute Salinity and Conservative Temperature that
    results when a given mass of sea ice (or ice) melts and is mixed into a
    known mass of seawater (whose properties are (SA,CT,p)).

    If the ice contains no salt (e.g. if it is of glacial origin), then the
    input 'SA_seaice' should be set to zero.

    Ice formed at the sea surface (sea ice) typically contains between 2 g/kg
    and 12 g/kg of salt (defined as the mass of salt divided by the mass of
    ice Ih plus brine) and this programme returns NaN's if the input
    SA_seaice is greater than 15 g/kg.  If the SA_seaice input is not zero,
    usually this would imply that the pressure p should be zero, as sea ice
    only occurs near the sea surface.  The code does not impose that p = 0
    if SA_seaice is non-zero.  Rather, this is left to the user.

    The Absolute Salinity, SA_brine, of the brine trapped in little pockets
    in the sea ice, is in thermodynamic equilibrium with the ice Ih that
    surrounds these pockets.  As the sea ice temperature, t_seaice, may be
    less than the freezing temperature, SA_brine is usually greater than the
    Absolute Salinity of the seawater at the time and place when and where
    the sea ice was formed.  So usually SA_brine will be larger than SA.

## INPUT:

    SA   =  Absolute Salinity of seawater                           [ g/kg ]
    CT   =  Conservative Temperature of seawater (ITS-90)          [ deg C ]
    p    =  sea pressure                                            [ dbar ]
              ( i.e. absolute pressure - 10.1325 dbar )
    w_seaice  =  mass fraction of sea ice, that is the mass of sea ice
                 divided by the sum of the masses of sea ice and seawater.
                 That is, the mass of sea ice divided by the mass of the
                 final mixed fluid.  w_seaice must be between 0 and 1.
                                                                [ unitless ]
    SA_seaice =  Absolute Salinity of sea ice, that is, the mass fraction of
                 salt in sea ice, expressed in g of salt per kg of sea ice.
                                                                    [ g/kg ]
    t_seaice  =  the in-situ temperature of the sea ice (or ice) (ITS-90)
                                                                   [ deg C ]

    SA, CT, w_seaice, SA_seaice & t_seaice must all have the same dimensions.
    p may have dimensions 1x1 or Mx1 or 1xN or MxN, where SA, CT, w_seaice,
    SA_seaice and t_seaice are MxN.

## OUTPUT:

    SA_final  =  Absolute Salinity of the mixture of the melted sea ice
                 (or ice) and the orignal seawater                  [ g/kg ]

    CT_final  =  Conservative Temperature of the mixture of the melted
                 sea ice (or ice) and the orignal seawater         [ deg C ]

## EXAMPLE:

    SA = [34.7118; 34.8915; 35.0256; 34.8472; 34.7366; 34.7324;]
    CT = [ 4.7856;  2.4329;  1.8103;  1.2600;  0.6886;  0.4403;]
    p =  [     10;      50;     125;     250;     600;    1000;]
    w_seaice = [0.0560; 0.02513; 0.02159; 0.01210; 0.00943; 0.00751;]
    SA_seaice = [     5;      4.8;     3.5;     2.5;     1;    0.4;]
    t_seaice = [-4.7856; -4.4329; -3.8103; -4.2600; -3.8863; -3.4036;]

    [SA_final, CT_final] = ...
     gsw_melting_seaice_into_seawater(SA,CT,p,w_seaice,SA_seaice,t_seaice)

    SA_final =

      33.047939199999995
      34.135300604999998
      34.344962295999999
      34.455798880000003
      34.418463862000003
      34.474563675999995

    CT_final =

      -0.018822367305381
       0.345095540241769
       0.020418581143151
       0.242672380976922
      -0.111078380121959
      -0.197363471215418

## AUTHOR:

    Trevor McDougall & 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.

    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