Contents
USAGE:
[drho_dSA, drho_dCT, drho_dP] = gsw_rho_first_derivatives_CT_exact(SA,CT,p)
DESCRIPTION:
Calculates the three (3) partial derivatives of in situ density with
respect to Absolute Salinity, Conservative Temperature and pressure.
Note that the pressure derivative is done with respect to pressure in
Pa, not dbar.
Note that this function uses the full Gibbs function. There is an
alternative to calling this function, namely
gsw_rho_first_derivatives(SA,CT,p), which uses the computationally
efficient 48-term expression for density in terms of SA, CT and p
(IOC et al., 2010).
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:
drho_dSA = partial derivatives of density [ kg^2/(g m^3) ]
with respect to Absolute Salinity
drho_dCT = partial derivatives of density [ kg/(K m^3) ]
with respect to Conservative Temperature
drho_dP = partial derivatives of density [ kg/(Pa m^3) ]
with respect to pressure in Pa
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;]
[drho_dSA, drho_dCT, drho_dP] = gsw_rho_first_derivatives_CT_exact(SA,CT,p)
drho_dSA =
0.733156846217923
0.733624383525935
0.743958873817461
0.771366026959394
0.777592352812266
0.781293756315164
drho_dCT =
-0.331799476403056
-0.329908681336511
-0.288047644037924
-0.177949875698853
-0.150633405019462
-0.133569084879840
drho_dP =
1.0e-006 *
0.420227501717672
0.420179717709499
0.426714635192923
0.447775625648340
0.452020205408281
0.454119774041303
AUTHOR:
Paul Barker and Trevor McDougall [ help@teos-10.org ]
VERSION NUMBER:
3.04 (10th December, 2013)
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 appendix A.20 and appendix K of this TEOS-10 Manual.
The software is available from http://www.TEOS-10.org