Hi Robb,
Thanks for the reply. Here's a sample of the output from gribtonc:
...
Apr 12 18:33:04 gribtonc[13809]: 27203: wrote reserved(107,11,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27204: wrote thnd_prob(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27205: wrote Pm(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27206: wrote Psl_et(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27207: wrote LI(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27208: wrote LI4(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27209: wrote Kind(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27210: wrote mois_div(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27211: wrote bvf_2(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27212: wrote gflux(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27213: wrote cape(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27214: wrote reserved(107,10,*,*) to output.nc
Apr 12 18:33:04 gribtonc[13809]: 27215: wrote thnd_prob(107,9,*,*) to output.nc
...
As far as sending a sample, unforunately the grib file is quite large
(~666mb) and I don't know how to subset that. Is there an easy way to do
that?
Thanks for the help!
Cheers,
Brent
On Tue, 20 Apr 2004, Robb Kambic wrote:
> Brent,
>
> If nobody has the proper cdl file then could you send me a sample file?
> My speculation is that a table is being used to convert variables from
> ECMWF variables to the NCEP variable names. Reason for the weird names.
> Also, what was the log messages from gribtonc like?
>
> Robb...
>
> On Tue, 20 Apr 2004, Brent A McDaniel wrote:
>
> >
> > I've just begun to use the ECMWF ERA40 data that is available from the
> > NCAR data archives. I'm using the 4x daily upper air pressure level data
> > that has 11 variables: geopotential, temperature, u wind component, v wind
> > component, w wind component, relative humidity, specific humidity,
> > vorticity, divergence, potential vorticity, ozone mass mixing ratio. The
> > data is archived in grib format for 1 month.
> >
> > Running wgrib -v e4oper.pl.195801 |more results in:
> > 1:0:D=1958010100:var60:1 mb:kpds=60,100,1:anl:ECMWF stream?:"undefined
> > 2:21240:D=1958010100:Z:1 mb:kpds=129,100,1:anl:ECMWF stream?:"Geopotential
(at the surface = orography) m**2 s**-2
> > 3:42480:D=1958010100:T:1 mb:kpds=130,100,1:anl:ECMWF stream?:"Temperature K
> > 4:63720:D=1958010100:U:1 mb:kpds=131,100,1:anl:ECMWF stream?:"U-velocity m
s**-1
> > 5:84960:D=1958010100:V:1 mb:kpds=132,100,1:anl:ECMWF stream?:"V-velocity m
s**-1
> > 6:106200:D=1958010100:Q:1 mb:kpds=133,100,1:anl:ECMWF stream?:"Specific
humidity kg kg**-1
> > 7:127440:D=1958010100:W:1 mb:kpds=135,100,1:anl:ECMWF stream?:"Vertical
velocity Pa s**-1
> > 8:148680:D=1958010100:VO:1 mb:kpds=138,100,1:anl:ECMWF stream?:"Vorticity
(relative) s**-1
> > 9:169920:D=1958010100:D:1 mb:kpds=155,100,1:anl:ECMWF stream?:"Divergence
s**-1
> > 10:191160:D=1958010100:R:1 mb:kpds=157,100,1:anl:ECMWF stream?:"Relative
humidity %
> > 11:212400:D=1958010100:O3:1 mb:kpds=203,100,1:anl:ECMWF stream?:"Ozone mass
mixing ratio kg kg**-1
> > 12:233640:D=1958010100:var60:2 mb:kpds=60,100,2:anl:ECMWF stream?:"undefined
> > ...
> >
> > which appears to be the variables that are supposed to be there although I
> > don't see potential vorticity (is that the undefined?).
> >
> > I then run gribtocdl to generate the .cdl file:
> > gribtocdl -v e4oper.pl.195801 > era40.jan.1958.cdl
> >
> > and then run gribtonc to convert to netcdf:
> > gribtonc -v -l- era40.jan.1958.cdl output.nc < e4oper.pl.195801
> >
> > This works properly and I get a netcdf file. When I look at it though,
> > all the variable names are wierd. Looking at the .cdl file I see that in
> > there the variable names aren't Z,T, U etc that were in the grib file
> > they are things like thund_prob, K index at isobaric levels, and other odd
> > things. The time is also off, showing the initial time as time since 1994
> > (data being tested was 1958). I did check one thing though. I plotted
> > the 3rd variable in the created netcdf file (which should be temperature)
> > and compared it the ncep reanalysis temperature field for jan 1958 and
> > they match up nicely so the data is somewhat correct.
> >
> > So, can someome help me out with this? Does anyone have a .cdl template
> > for the ERA40 data set already? I'm most concerned with the time
> > variables as I'm not sure exactly how grib keeps track of time.
> >
> > Thanks for any and all help.
> >
> > Cheers,
> >
> > Brent
> >
> > --
> > Brent A. McDaniel
> >
> > Dept of Earth and Atmospheric Sciences
> > Georgia Institute of Technology
> > Atlanta, Ga. USA
> >