gsw_rho_alpha_beta

in-situ density, thermal expansion & saline 
contraction coefficient (75-term equation)

Contents

USAGE:

[rho, alpha, beta] = gsw_rho_alpha_beta(SA,CT,p)

DESCRIPTION:

Calculates in-situ density, the appropiate thermal expansion coefficient
and the appropriate saline contraction coefficient of seawater from
Absolute Salinity and Conservative Temperature.  This function uses the
computationally-efficient 75-term expression for specific volume in terms
of SA, CT and p (Roquet et al., 2015).
Note that the 75-term equation has been fitted in a restricted range of 
parameter space, and is most accurate inside the "oceanographic funnel" 
described in McDougall et al. (2003).  The GSW library function 
"gsw_infunnel(SA,CT,p)" is avaialble to be used if one wants to test if 
some of one's data lies outside this "funnel".
TEOS-10 
Click for a more detailed description of rho, alpha
and beta.

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:

rho    =  in-situ density                                     [ kg/m^3 ]
alpha  =  thermal expansion coefficient                          [ 1/K ]
          with respect to Conservative Temperature
beta   =  saline contraction coefficient                        [ kg/g ]
          at constant Conservative Temperature

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;]
[rho, alpha, beta] = gsw_rho_alpha_beta(SA,CT,p)
rho =
1.0e+003 *
   1.021839935738108
   1.022262457966867
   1.024427195413316
   1.027790152759127
   1.029837779000189
   1.032002453224572
alpha =
1.0e-003 *
   0.324638934509245
   0.322655537959731
   0.281145723210171
   0.173199716344780
   0.146289673594824
   0.129414845334599
beta =
1.0e-003 *
   0.717483987596135
   0.717647512290095
   0.726211643644768
   0.750500751749777
   0.755052064788492
   0.757050813384370

AUTHOR:

Paul Barker and Trevor McDougall          [ 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.
  See appendix A.20 and appendix K of this TEOS-10 Manual.
McDougall, T.J., D.R. Jackett, D.G. Wright and R. Feistel, 2003: 
 Accurate and computationally efficient algorithms for potential 
 temperature and density of seawater.  J. Atmosph. Ocean. Tech., 20,
 pp. 730-741.
Roquet, F., G. Madec, T.J. McDougall and P.M. Barker, 2015: Accurate
 polynomial expressions for the density and specific volume of seawater 
 using the TEOS-10 standard.  Ocean Modelling, 90, pp. 29-43. 
 http://dx.doi.org/10.1016/j.ocemod.2015.04.002
The software is available from http://www.TEOS-10.org