# gsw_enthalpy_CT25

    enthalpy of seawater (25-term equation)

## Contents

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

## USAGE:

    [enthalpy, in_funnel] =  gsw_enthalpy_CT25(SA,CT,p)

## DESCRIPTION:

    Calculates specific enthalpy of seawater using the computationally-
    efficient 25-term expression for density in terms of SA, CT and p
    (McDougall et al., 2010)

    Click for a more detailed description of enthalpy
    calculated with the 25-term equation.

## INPUT:

    SA   =  Absolute Salinity                                       [ g/kg ]
    CT   =  Conservative Temperature                               [ deg C ]
    p    =  sea pressure                                            [ dbar ]
           (ie. absolute pressure - 10.1325 dbar)

    SA & CT need to have the same dimensions.
    p may have dimensions 1x1 or Mx1 or 1xN or MxN, where SA & CT are MxN.

## OUTPUT:

    enthalpy   =  specific enthalpy                                 [ J/kg ]
    in_funnel  =  0, if SA, CT and p are outside the "funnel"
               =  1, if SA, CT and p are inside the "funnel"
    Note. The term "funnel" describes the range of SA, CT and p over which
      the error in the fit of the computationally-efficient 25-term
      expression for density was calculated (McDougall et al., 2010).

## EXAMPLE:

    SA = [34.7118; 34.8915; 35.0256; 34.8472; 34.7366; 34.7324;]
    CT = [28.8099; 28.4392; 22.7862; 10.2262;  6.8272;  4.3236;]
    p =  [     10;      50;     125;     250;     600;    1000;]

    [enthalpy, in_funnel] =  gsw_enthalpy_CT25(SA,CT,p)

    enthalpy =                     in_funnel =

    1.0e+005 *

     1.151031813925039               1
     1.140146929487063               1
     0.921800148514069               1
     0.432553660538842               1
     0.330871524935877               1
     0.269706799089967               1

## AUTHOR:

    Trevor McDougall, David Jackett, Claire Roberts-Thomson and Paul Barker.
                                                [ help_gsw@csiro.au ]

## VERSION NUMBER:

    2.0 (26th August, 2010)

## 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 Eqn. (A.30.6) of this TEOS-10 Manual.

    McDougall T. J., D. R. Jackett, P. M. Barker, C. Roberts-Thomson, R.
     Feistel and R. W. Hallberg, 2010:  A computationally efficient 25-term
     expression for the density of seawater in terms of Conservative
     Temperature, and related properties of seawater.  To be submitted
     to Ocean Science Discussions.

    The software is available from http://www.TEOS-10.org