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20010215: AVN grids

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  • Subject: 20010215: AVN grids
  • Date: Thu, 15 Feb 2001 14:31:47 -0700

Lodovica,

The AVN grids from NOAAPORT (eg the ones on the IDD) generally
have levels up to 100 millibars. From your message, I presume you are 
interested in stratospheric levels above 100 millibars.

The 1x1 degree global AVN grids on the NCEP ftp server do contain
levels above 100mb (70mb, 50mb, 30mb, 20mb, 10mb) with parameters
of HGHT, UREL, VREL, OZMR (ozone), TMPK, AVOR.

You can ftp these grids from:
ftp://ftp.ncep.noaa.gov/pub/data1/avn/avn.yymmdd/

The files you are lokking for are named:
gblav.TxxZ.PGrbFff
where xx is the forecast run and ff is the forecast hour.

The PGrb files are the grib files. (the PGrbi files are index
files...not useful for GEMPAK).

You can decode the files with dcgrib, dcgrib2 or nagrib.
If you are running GEMPAK 5.6 or 5.6a, there is a patch file for dcgrib2
for the GRID 003 that the AVN above uses to correctly flip them North/South-
this is in ~gbuddy/nawips-5.6/patches/dcgrib2/dcwppg.c and should be
installed in $NAWIPS/unidata/ldmbridge/dcgrib2 directory. The decoder can
be rebuilt with: cd $NAWIPS/unidata/ldmbridge/dcgrib2    then,
make clean
make all
make install
make clean

This is only a bug with dcgrib2 and not dcgrib or nagrib.

Steve Chiswell
Unidata User Support





>From: Lodovica Illari <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200102152004.f1FK4mL03680

>Hi,
>
>here at MIT we are interested in global stratospheric analyses. 
>Do you know if the AVN grid we ingest contains model level data?
>If so, how can we gempak them?
>
>Thanks
>
>Lodovica Illari
>
>
>
>From address@hidden Mon Feb 12 13:24:58 2001
>Received: from wind.mit.edu (WIND.MIT.EDU [18.83.0.213])
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>       for <address@hidden>; Mon, 12 Feb 2001 13:24:58 -0700 (MST)
>Organization: UCAR/Unidata
>Keywords: 200102122024.f1CKOwL04103
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>       for address@hidden; Mon, 12 Feb 2001 15:24:57 -0500 (EST)
>Date: Mon, 12 Feb 2001 15:24:57 -0500 (EST)
>From: Lodovica Illari <address@hidden>
>Message-Id: <address@hidden>
>To: address@hidden
>Subject: AVN model data
>
>
>Hi,
>
>here at MIT we are receiving the AVN grids through the IDD and
>we have been using the pressure levels data after Gempaking
>the data with DCGRIB.
>
>Is the model level data available as well and how can I gempak it?
>
>Thanks
>
>Lodovica Illari
>