Contents
USAGE:
[h_SA_SA, h_SA_CT, h_CT_CT] = gsw_enthalpy_2nd_derivatives(SA,CT,p)
DESCRIPTION:
Calculates the following three second-order derivatives of specific
enthalpy (h),
(1) h_SA_SA, second order derivative with respect to Absolute Salinity
at constant CT & p.
(2) h_SA_CT, second order derivative with respect to SA & CT at
constant p.
(3) h_CT_CT, second order derivative with respect to CT at constant
SA & p.
INPUT:
SA = Absolute Salinity [ g/kg ]
CT = Conservative Temperature [ deg C ]
p = sea pressure [ dbar ]
(i.e. 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:
h_SA_SA = The second derivative of specific enthalpy with respect to
Absolute Salinity at constant CT & p. [ J/(kg (g/kg)^2) ]
h_SA_CT = The second derivative of specific enthalpy with respect to
SA and CT at constant p. [ J/(kg K(g/kg)) ]
h_CT_CT = The second derivative of specific enthalpy with respect to
CT at constant SA and p. [ J/(kg K^2) ]
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 = [ 10; 50; 125; 250; 600; 1000;]
[h_SA_SA, h_SA_CT, h_CT_CT] = gsw_enthalpy_second_derivatives(SA,CT,p)
h_SA_SA =
0.000082752219662
0.000414449264358
0.001089849221923
0.002473058502734
0.006107254340947
0.010388021033928
h_SA_CT =
0.000130254397677
0.000654928172110
0.001880402010403
0.005474186056408
0.014339376841409
0.025245467907619
h_CT_CT =
0.000714090119067
0.003584609310758
0.009736868475975
0.024061418823850
0.061537073639407
0.107564288175526
AUTHOR:
Trevor McDougall 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 Notes on the first and second order isobaric derivatives of
specific enthalpy.
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.
This software is available from http://www.TEOS-10.org