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[CONDUIT #WGH-452695]: LDM/PQACT incantation for CONDUIT 0.5deg GFS

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  • Subject: [CONDUIT #WGH-452695]: LDM/PQACT incantation for CONDUIT 0.5deg GFS
  • Date: Fri, 17 Aug 2007 09:48:33 -0600
> Thanks for the quick reply!
> 
> Does this mean the files from LDM do not require "stitching" together?
> (that is, no concatenation needed?)
> 
> -Donna


Donna,

The GFS 0.5 degree are on GRID #4, which is a single global grid. No tiles.

You can find out more about the various grids in use at:
http://www.nco.ncep.noaa.gov/pmb/docs/on388/tableb.html

The GFS grids in the HRS data stream called the quasi thinned grids
numbers 37-44 are 8 1.25 degree tiles that have to be stitched together for
a global data set. The CONDUIT grids are a higher temporal and spatial
resolution, with many more parameters than the HRS grids.

Steve Chiswell
Unidata User Support


> 
> Unidata CONDUIT Support wrote:
> >> With a pair of tropical storms bearing down on us, I've now forgotten
> >> how to snag all the GFS 0.5 deg products and concatenate them into a
> >> consistent grib2 3-hourly file.  Could I beg for some help?
> >>
> >> Thanks gerry
> >>
> >>
> >>
> >
> > Gerry,
> >
> > The cannonical naming is provided on the conduit web page:
> > http://www.unidata.ucar.edu/data/conduit/ldm_idd/gfs_files.html
> >
> > To file individual times into separate grib files, something like:
> >
> > CONDUIT <tab> (gfs)\.(..........)/.*(pgrb2)(.*) !.*!
> > <tab> FILE <tab>  data/\1/\2\4.\3
> >
> > Note that the forecast time matched by field 4 above can be either
> > "anl", "fxx", or "fxxx"  so you have both 2 and 3 digit hour possibilities
> > as well as the string "anl". The important part above is to use the "pgrb2"
> > string in the pattern which will only match the 0.5 degree files in grib2
> > as the 1.0 degree and 2.5 degree files are "pgrb" without the version 2.
> >
> > The decoding in GEMPAK is as simple as sending gfs.*pgrb2 to dcgrib2
> > as shown in the $NAWIPS/ldm/etc/templates/pqact.gempak_decoders.in file.
> >
> > Steve Chiswell
> > Unidata User Support
> >
> > Ticket Details
> > ===================
> > Ticket ID: WGH-452695
> > Department: Support CONDUIT
> > Priority: Normal
> > Status: Closed
> >
> --
> Donna Cote
> Senior Research Associate
> The Academy for Advanced Telecommunications and Learning Technologies
> Texas A&M University
> 3139 TAMU
> College Station, Texas 77843-3139
> Office: (979) 862-3982
> Cell: (979) 324-3549
> Fax: (979) 862-3983
> 
> 


Ticket Details
===================
Ticket ID: WGH-452695
Department: Support CONDUIT
Priority: Normal
Status: Closed