[gradsusr] Extracting time specific grib data using wgrib

[Davide Sacchetti]

I don't understand perfectly, but you could:

1) extract data on surface with wgrib ... | wgrib -grib -i
2) append data on pressure levs with wgrib ... | wgrib -append -grib -i
... 

furthermore you can always join different grib datasets:
cat dataset_surface dataset_levels > dataset_all
or
cat dataset_surface >> dataset_levels

pay attention that grads works ONLY with the two datasets are on the
same horizontal grid

Davide

On Mon, 2018-05-07 at 20:06 +0000, Charles Vanya wrote:
> Dear David, 
> Your direction worked perfectly. Now another question would be, is it
> possible to combine variables extracted from grib data on the surface
> and grib data at different pressure levels such that in the end i
> should have all pressure level variables and  surface or ground
> variables? In the end i just need one grib data set file that
> contains variables from two different files with different levels as
> well.
> Your 
> Charles Vanya
> 
> Sent from Yahoo Mail on Android
> 
> > On Mon, 7 May 2018 at 10:02, Davide Sacchetti
> > <davide.sacchetti at arpal.gov.it> wrote:
> > wgrib all_cosmodata | grep ':78hr fcst:' | egrep -i ":VGRD:|:UGRD:"
> > \
> > | wgrib -grib -i  all_cosmodata
> > 
> > (in our suite U:kpds5=33:kpds6=110 -> UGRD)
> > 
> > 
> > bye bye
> > Davide
> > 
> > On Mon, 2018-05-07 at 05:07 +0000, Charles Vanya wrote:
> > > Dear All,
> > > I am humbly looking for assistance. I have hourly data from COSMO
> > > model which span for 78 hours and is in grib format. I would like
> > to
> > > extract specific variables for the whole 78hours and concatenate
> > it
> > > as one grib file.
> > > I have tried to concatenate the files and when i run the wgrib
> > > command to extract the variables i am looking for, i am only
> > getting
> > > data file for 2 days.
> > > I started like this:
> > > cat lfff00000000c lfff*00 > all_cosmodata
> > >  To extract for specific variables
> > > wgrib all_cosmodata | egrep -i
> > > ":V:kpds5=34:kpds6:=110:|:U:kpds5=33:kpds6=110:" | wgrib -grep 
> > -i
> > > all_cosmodata -o cosmodata_uv
> > > Here am trying to extract surface u and v component of wind for
> > all
> > > 78hrs.
> > > However my output shows me that i have only extracted two hours
> > data.
> > > Now my question is, how can i include the time steps so that i
> > > extract all 78 hrs at once.
> > > Your assistance will be highly appreciated.
> > > Charles Langton Vanya
> > > Chief Meteorological
> > > Prediction Section
> > > Dept. of Climate Change and Meteorological Services
> > > P.O.Box 1808,
> > > Blantyre.
> > > Malawi
> > > Tel:+265888980545
> > > Sent from Yahoo Mail on Android
> > 
> > > _______________________________________________
> > > gradsusr mailing list
> > > gradsusr at gradsusr.org
> > > http://gradsusr.org/mailman/listinfo/gradsusr
> > 
> > _______________________________________________
> > gradsusr mailing list
> > gradsusr at gradsusr.org
> > http://gradsusr.org/mailman/listinfo/gradsusr
> >