def dynamic_enthalpy_CT_exact(SA, CT, p):
r"""Calculates the dynamic enthalpy of seawater from Absolute Salinity and
Conservative Temperature and pressure. Dynamic enthalpy is defined as
enthalpy minus potential enthalpy (Young, 2010).
Parameters
----------
SA : array_like
Absolute Salinity [g/kg]
CT : array_like
Conservative Temperature [:math:`^\circ` C (ITS-90)]
p : array_like
sea pressure [dbar]
Returns
-------
dynamic_enthalpy_CT_exact : array_like
dynamic enthalpy [J/kg]
See Also
--------
TODO
Notes
-----
This function uses the full Gibbs function. There is an alternative to
calling this function, namely dynamic_enthalpy(SA, CT, p), which uses the
computationally efficient 48-term expression for density in terms of SA, CT
and p (McDougall et al., 2011).
Examples
--------
TODO
References
----------
.. [1] 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. See apendix A.30.
.. [2] McDougall T.J., P.M. Barker, R. Feistel and D.R. Jackett, 2011: A
computationally efficient 48-term expression for the density of
seawater in terms of Conservative Temperature, and related properties
of seawater.
.. [3] Young, W.R., 2010: Dynamic enthalpy, Conservative Temperature, and
the seawater Boussinesq approximation. Journal of Physical Oceanography,
40, 394-400.
Modifications:
2011-04-05. Trevor McDougall and Paul Barker.
"""
t = t_from_CT(SA, CT, p)
return enthalpy_t_exact(SA, t, p) - cp0 * CT
def enthalpy_diff_CT_exact(SA, CT, p_shallow, p_deep):
r"""Calculates the difference of the specific enthalpy of seawater between
two different pressures, p_deep (the deeper pressure) and p_shallow (the
shallower pressure), at the same values of SA and CT. The output
(enthalpy_diff_CT_exact) is the specific enthalpy evaluated at
(SA, CT, p_deep) minus the specific enthalpy at (SA,CT,p_shallow).
parameters
----------
Parameters
----------
SA : array_like
Absolute Salinity [g/kg]
CT : array_like
Conservative Temperature [:math:`^\circ` C (ITS-90)]
p_shallow : array_like
lower sea pressure [dbar]
p_deep : array-like
upper sea pressure [dbar]
returns
-------
enthalpy_diff_CT_exact : array_like
difference of specific enthalpy [J/kg]
(deep minus shallow)
See Also
--------
TODO
Notes
-----
This function uses the full Gibbs function. There is an alternative to
calling this function, namely enthalpy_diff_CT(SA, CT, p), which uses the
computationally efficient 48-term expression for density in terms of SA, CT
and p (McDougall et al., 2011).
Examples
--------
TODO
References
----------
.. [1] 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. See Eqns (3.32.2).
.. [2] McDougall T.J., P.M. Barker, R. Feistel and D.R. Jackett, 2011: A
computationally efficient 48-term expression for the density of
seawater in terms of Conservative Temperature, and related properties
of seawater.
Modifications:
2011-04-06. Trevor McDougall and Paul Barker.
"""
t_shallow = t_from_CT(SA, CT, p_shallow)
t_deep = t_from_CT(SA, CT, p_deep)
return (enthalpy_t_exact(SA, t_deep, p_deep) -
enthalpy_t_exact(SA, t_shallow, p_shallow))
