Hello,
>I have ECMWF model level data set and would like to convert it to pressure
level. I am trying to use vinth2p function. I know this function is for CCSM
coordinate with p = AP+ BP(i,j)
Are you talking about the ERA40 Reanalysis archive?
There are several parts to this response:
[1] ------------------------------------------------
>
>May I ask can I use this function to convert ECMWF coordinate?
>Can I use vinth2p for this purpose?
>
yes but note that this function was based upon the
vertical ordering used by the NCAR atmospheric model .. top-to-bottom.
>What I am trying is to use function vinth2p with EC's A and B but set p0mb = 1,
rather than 1000mb, and pp is the surface (hPa) to convert a EC variable "temp"
from its hybrid coordinate to pressure level as followed:
>
> vinth2p (temp, hyam, hybm, lev_p, pp(0,:,:), intyp, p0mb, 1, False )
>
Tp = vinth2p (temp, hyam, hybm, lev_p, pp(0,:,:), intyp, p0mb, 1, False )
for Tp at the initial time only ==>Tp(lev_p,lat,lon)
Tp = vinth2p (temp, hyam, hybm, lev_p, pp, intyp, p0mb, 1, False )
for Tp at all times ==>Tp(time,lev_p,lat,lon)
printVarSummary(Tp)
So ... YES ... NCL can be (and has been) used to do this.
============
[2] I forwarded your question to NCAR's Data Support Section (DSS).
The response has been posted to ncl-talk.
==============
[3] The dataset produced by DSS are in GRIB format. DSS does
this to minimize file size.
NCL can read these directly. Let's say there are
a number of files in some directory; further,
they all begin with U*
dirg = "./" ; directory where GRIB file reside
filg = systemfunc("cd "+dirg +"; ls U*) ; grib file names
nfil = dimsizes(filg) ; number of files
do nf=0,nfil-1
f = addfile (dirg+fil(nf)+".grb", "r") ; extension identifies the
; file as a GRIB file
;print(f) ; view file contents
z = f->Z_GDS4_ISBL
:
end do
================
[4] If you *need* to make netCDF files, I can send you an
NCL script that will convert GRIB to netCDF.
================
Good luck
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