Re: Error in ECHAM pressure levels.

From: Dennis Shea <shea_at_nyahnyahspammersnyahnyah>
Date: Tue Feb 23 2010 - 07:11:00 MST

http://www.ncl.ucar.edu/Document/Functions/Built-in/pres_hybrid_ccm.shtml

Please read the function description. Example 3.
At each grid point you will get the pressure at
each hybrid levels.

--
f you want to interpolate the constant pressure levels
http://www.ncl.ucar.edu/Document/Functions/Built-in/vinth2p.shtml
or
http://www.ncl.ucar.edu/Document/Functions/Built-in/vinth2p.shtml
These expect the hybri coefficients to be
     p = a[:]*p0 + b[:]*ps
You will have to change your coefficients to match those
expected by the function.
A.R Ragi wrote:
> 
> Dear NCL users..,
> 
> I want to calculate the equation which is for converting ECHAM 31 levels 
> to pressure levels in hPa.
> 
> 1 level is 1000hPa and 31 level is 10 hPa.
> 
> 
> The equation written in model to calculate pressure levels is:
> 
> 
> *P(lev) =a(lev)+b(lev)*Ps(time,lat,lon)
> 
> a* and* b* are hybrid coefficient which is in the model output.
> and *Ps *also in the model output.
>  
> But *a and b *are one dimensional but Ps is three dimensional.
> 
> *a(31),  b(31)  but Ps (30,192,96)*
> 
> 
> 
> The error saying *P(lev) *is undefined.
> 
> Means it is not calculating the equation.
> 
> Is this because of matrix multiplication needed for this case?
> 
> Thanks in advance.
> */
> 
> Code:/*
> 
> 
> begin
> 
> echam_out = addfile("/....../test_2003.06.nc <http://test_2003.06.nc>","r")
> 
> 
>   A = echam_out->hyam(:)
>   B = echam_out->hybm(:)
>   Ps = echam_out->aps(:,:,:)
>  
>  
> do k = 1,31
> 
>         do j = 1,96
> 
>                 do i = 1,192
> 
> 
>                         P(k) = A(k)+B(k)* Ps(1,i,j)
> 
> 
>                         asciiwrite("P.txt",P(1,1,k))
> 
> 
>                  end do
> 
>         end do
> 
> end do
> 
> end
> 
> 
> 
> fatal:Undefined identifier: (P) is undefined, can't continue
> fatal:Execute: Error occurred at or near line 46 in file Pvalues.ncl
> 
> 
> 
> 
> 
> -- 
> *********************************************************************
> Thanks,
> A.R.Ragi
> M.Tech Atmospheric science
> Department of Atmospheric science
> Cochin University of Science and Technology
> Email : ar.ragi@gmail.com <mailto:ar.ragi@gmail.com>  
> 
> 
> 
> 
> 
> ------------------------------------------------------------------------
> 
> _______________________________________________
> ncl-talk mailing list
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
Received on Tue Feb 23 07:11:04 2010

This archive was generated by hypermail 2.1.8 : Tue Feb 23 2010 - 08:26:41 MST