# gsw_alpha_on_beta_CT_exact

    thermal expansion divided by the saline
    contraction coefficient

## Contents

- USAGE:
- DESCRIPTION:
- INPUT:
- OUTPUT:
- EXAMPLE:
- AUTHOR:
- VERSION NUMBER:
- REFERENCES:

## USAGE:

    alpha_on_beta_CT_exact = gsw_alpha_on_beta_CT_exact(SA,CT,p)

## DESCRIPTION:

    Calculates alpha divided by beta, where alpha is the thermal expansion
    coefficient and beta is the saline contraction coefficient of seawater
    from Absolute Salinity and Conservative Temperature.

    Note that this function uses the full Gibbs function.  There is an
    alternative to calling this function, namely gsw_alpha_on_beta(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).

    Click for a more detailed description of
    alpha on 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:

    alpha_on_beta_CT_exact  =  thermal expansion coefficient with respect
                               to Conservative Temperature divided by the
                               saline contraction coefficient at constant
                               Conservative Temperature.    [ kg g^-1 K^-1 ]

## 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;]

    alpha_on_beta_CT_exact = gsw_alpha_on_beta_CT_exact(SA,CT,p)

    alpha_on_beta_CT_exact =

       0.452562747132054
       0.449696995826268
       0.387182214199383
       0.230694468617323
       0.193717703723134
       0.170958853568465

## 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.

    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.

    The software is available from http://www.TEOS-10.org