[ncl-talk] using TEOS10 software with NCL

[william.llovel@cerfacs.fr]

Dear all,

I am an oceanographer and a new NCL user. I am interested in the ocean 
heat content change and its contribution to sea level.
Thus, I need to compute some parameters as density, heat capacity 
etc.... For that, I need to use the equation of state of the ocean.
The recommendation is now to consider the TEOS-10 software available at 
http://www.teos-10.org/ .
This website provides a set of fortran90 functions and subroutines.
I have tried to call them using the WRAPIT command : 
https://www.ncl.ucar.edu/Document/Tools/WRAPIT.shtml#Step_1
first, by creating a stub file and then, runing the WRAPIT command. 
Unfortunately, this does not work. the results are wrong and totally 
unphysical.

this is why I am contacting you and asking your help.

Below is an example of the F90 function.

!==========================================================================
function gsw_sa_from_sp(sp,p,lon,lat)
!==========================================================================

! Calculates Absolute Salinity, SA, from Practical Salinity, SP
!
! sp     : Practical Salinity                              [unitless]
! p      : sea pressure                                    [dbar]
! lon   : lonitude                                       [DEG E]
! lat    : latitude                                        [DEG N]
!
! gsw_sa_from_sp   : Absolute Salinity                     [g/kg]

implicit none
integer, parameter :: r14 = selected_real_kind(14,30)

real (r14) :: sp, lon, lat, p, gsw_sa_from_sp, gsw_saar, saar
real (r14) :: gsw_sa_baltic, gsw_sa_from_sp_baltic

saar = gsw_saar(p,lon,lat)

gsw_sa_from_sp = (35.16504d0/35.d0)*sp*(1.d0 + saar)
!==========================================================================

And my stub file before invoking WRAPIT.

!==========================================================================
C NCLFORTSTART
       function gsw_sa_from_sp(sp,p,lon,lat)
       double precision sp, lon, lat, p
C NCLEND
!==========================================================================

I am able to run the WRAPIT command and create the file.so, but when I 
try to call a function or subroutine with NCL, the results are totally 
wrong.

I think this is because of this line : integer, parameter :: r14 = 
selected_real_kind(14,30) in the F90 functions that defines my variables.

If you have any idea on how I could resolve this issue, I will be more 
than happy to hear from you.

This toolbox is very important for any oceanographer. So, implementing 
this toolbox into NCL will motive more researchers to use your software.

Thanks for your help,

Best regards,

William