Contents
USAGE:
[u_SA_SA, u_SA_CT, u_CT_CT, u_SA_P, u_CT_P] = ...
gsw_internal_energy_second_derivatives_CT_exact(SA,CT,p)
DESCRIPTION:
Calculates the following five second-order derivatives of
internal energy,
(1) u_SA_SA, second order derivative with respect to Absolute Salinity
at constant CT & p.
(2) u_SA_CT, second order derivative with respect to SA & CT at
constant p.
(3) u_CT_CT, second order derivative with respect to CT at constant
SA & p.
(4) u_SA_P, second-order derivative with respect to SA & P at
constant CT.
(5) u_CT_P, second-order derivative with respect to CT & P at
constant SA
Note that this function uses the full Gibbs function. There is an
alternative to calling this function, namely
gsw_internal_energy_second_derivatives(SA,CT,p), which uses the
computationally efficient 75-term expression for specific volume in
terms of SA, CT and p (Roquet et al., 2015).
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:
u_SA_SA = The second derivative of internal energy with respect to
Absolute Salinity at constant CT & p. [ (J/kg)(g/kg)^-2 ]
u_SA_CT = The second derivative of internal energy with respect to
SA & CT at constant p. [ (J/kg)(g/kg)^-1 K^-1]
u_CT_CT = The second derivative of internal energy with respect to
CT at constant SA and p. [ (J/kg) K^-2 ]
u_SA_P = The second derivative of internal energy with respect to
SA & P at constant CT. [ (J/kg)(g/kg)^-1 Pa^-1 ]
u_CT_P = The second derivative of internal energy with respect to
CT & P at constant SA. [ (J/kg) K^-1 Pa^-1 ]
EXAMPLE:
SA = [34.7118; 34.8915; 35.0256; 34.8472; 34.7366; 34.7324;]
CT = [28.7856; 28.4329; 22.8103; 10.2600; 6.8863; 4.4036;]
p = [ 10; 50; 125; 250; 600; 1000;]
[u_SA_SA, u_SA_CT, u_CT_CT, u_SA_P, u_CT_P] = ...
gsw_internal_energy_second_derivatives_CT_exact(SA,CT,p)
u_SA_SA =
1.0e-04 *
-0.083825343496748
-0.083416792635045
-0.084948480848605
-0.085554093346234
-0.014989876934701
0.151822855467358
u_SA_CT =
1.0e-03 *
-0.131960094412962
-0.131426154575457
-0.143661243353954
-0.176542994620612
0.038873103109403
0.578487406867507
u_CT_CT =
-0.000723400187344
-0.000719998992295
-0.000745814518760
-0.000736301199729
0.000456106079104
0.003383686798365
u_SA_P =
1.0e-07 *
-0.002355222222595
-0.007035025555756
-0.016468311540362
-0.035407474852142
-0.084808691842265
-0.141942939648594
u_CT_P =
1.0e-07 *
-0.001718583707015
-0.005204387424044
-0.015207379618322
-0.049042313140502
-0.129085760730138
-0.230817132562563
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.
Roquet, F., G. Madec, T.J. McDougall, P.M. Barker, 2015: Accurate
polynomial expressions for the density and specifc volume of seawater
using the TEOS-10 standard. Ocean Modelling.
This software is available from http://www.TEOS-10.org