Contents
USAGE:
[CT_SA_wrt_t, CT_T_wrt_t, CT_P_wrt_t] = gsw_CT_first_derivatives_wrt_t_exact(SA,t,p)
DESCRIPTION:
Calculates the following three derivatives of Conservative Temperature.
These derivatives are done with respect to in-situ temperature t (in the
case of CT_T_wrt_t) or at constant in-situ tempertature (in the cases of
CT_SA_wrt_t and CT_P_wrt_t).
(1) CT_SA_wrt_t, the derivative of CT with respect to Absolute Salinity
at constant t and p, and
(2) CT_T_wrt_t, derivative of CT with respect to in-situ temperature t
at constant SA and p.
(3) CT_P_wrt_t, derivative of CT with respect to pressure P (in Pa) at
constant SA and t.
This function uses the full Gibbs function. Note that this function
avoids the NaN that would exist in CT_SA_wrt_t at SA = 0 if it were
evaluated in the straightforward way from the derivatives of the Gibbs
function function.
INPUT:
SA = Absolute Salinity [ g/kg ]
t = in-situ temperature (ITS-90) [ deg C ]
p = sea pressure [ dbar ]
( ie. absolute pressure - 10.1325 dbar )
SA & t need to have the same dimensions.
p may have dimensions 1x1 or Mx1 or 1xN or MxN, where SA & t are MxN.
OUTPUT:
CT_SA_wrt_t = The first derivative of Conservative Temperature with
respect to Absolute Salinity at constant t and p.
[ K/(g/kg)] i.e. [ K kg/g ]
CT_T_wrt_t = The first derivative of Conservative Temperature with
respect to in-situ temperature, t, at constant SA and p.
[ unitless ]
CT_P_wrt_t = The first derivative of Conservative Temperature with
respect to pressure P (in Pa) at constant SA and t.
[ K/Pa ]
EXAMPLE:
SA = [34.7118; 34.8915; 35.0256; 34.8472; 34.7366; 34.7324;]
t = [28.7856; 28.4329; 22.8103; 10.2600; 6.8863; 4.4036;]
p = [ 10; 50; 125; 250; 600; 1000;]
[CT_SA_wrt_t, CT_T_wrt_t, CT_P_wrt_t] = ...
gsw_CT_first_derivatives_wrt_t_exact(SA,t,p)
CT_SA_wrt_t =
-0.041988694538987
-0.041596549088952
-0.034853545749326
-0.019067140454607
-0.015016439826591
-0.012233725491373
CT_T_wrt_t =
1.002752642867571
1.002243118597902
1.000835702767227
0.998194915250648
0.995219303532390
0.991780205482695
CT_P_wrt_t =
1.0e-007 *
-0.241011880838437
-0.239031676279078
-0.203649928441505
-0.119370679226136
-0.099140832825342
-0.086458168643579
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.
This software is available from http://www.TEOS-10.org