Contents
USAGE:
[enthalpy_diff, in_funnel] =
gsw_enthalpy_diff_CT25(SA,CT,p_shallow,p_deep)
DESCRIPTION:
Calculates the difference of the specific enthalpy of seawater between
two different pressures, p_deep (the deeper pressure) and p_shallow
(the shallower pressure), at the same values of SA and CT. This
function uses the computationally-efficient 25-term expression for
density in terms of SA, CT and p (McDougall et al., 2010). The output
(enthalpy_diff) is the specific enthalpy evaluated at (SA, CT, p_deep)
minus the specific enthalpy at (SA, CT, p_shallow).
INPUT:
SA = Absolute Salinity [ g/kg ]
CT = Conservative Temperature [ deg C ]
p_shallow = upper sea pressure [ dbar ]
(ie. shallower absolute pressure - 10.1325 dbar)
p_deep = lower sea pressure [ dbar ]
(ie. deeper absolute pressure - 10.1325 dbar)
p_shallow and p_deep may have dimensions Mx1 or 1xN or MxN,
where SA and CT are MxN.
OUTPUT:
enthalpy_diff = difference of specific enthalpy [ J/kg ]
(deep minus shallow)
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;]
t = [28.7856; 28.4329; 22.8103; 10.2600; 6.8863; 4.4036;]
p_shallow = [ 10; 50; 125; 250; 600; 1000;]
p_deep = [ 110; 150; 225; 350; 700; 1100;]
[enthalpy_diff, in_funnel] = ...
gsw_enthalpy_diff_CT25(SA,CT,p_shallow,p_deep)
enthalpy_diff = in_funnel =
1.0e+002 *
9.784262827561797 1
9.780221873372307 1
9.759531141438936 1
9.727477253978700 1
9.708128690308879 1
9.687770260315075 1
AUTHOR:
Trevor McDougall & Claire Roberts-Thomson. [ 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 Eqns. (3.32.2) and (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