RE: grib to netcdf conversion question

• To: "Ross,Charles H - PGPW-5" <cxross@xxxxxxx>
• Subject: RE: grib to netcdf conversion question
• From: Robb Kambic <rkambic@xxxxxxxxxxxxxxxx>
• Date: Thu, 15 Feb 2007 08:38:35 -0700 (MST)

Charles,

if you make a sample file available on the web, i'll take a look at it for

ya.

robb...



On Tue, 13 Feb 2007, Ross,Charles H - PGPW-5 wrote:

Thanks Robb and everyone else for replying so far, this has been very hel

pful.

From what I've read so far, it appears that it is not possible to take a

model grib file (grib 1 format) and send it through the gribtocdl process
and have the netcdf output be readable in the GFE/IFPS software (not necess
arily an awips d2d).

It sounds like only the nws awips grib decoder which produces their versi

on of netcdf (again, so much for standards!) output for use in the gfe/ifps
(or an awips d2d).

Is this a correct assumption, or has anyone been able to display model da

ta on gfe/ifps not using the nws grib decoder?

I have not tried using the Java Grib libraries yet, I was unclear from Ro

bb's last message if that will get me to where I want to go on this.

Thanks again for everyone's help on this; I am very thankful for this for

um.   Have a great day everyone!

-Charles



-----Original Message-----
From: Robb Kambic [mailto:rkambic@xxxxxxxxxxxxxxxx]
Sent: Tuesday, February 13, 2007 7:50 AM
To: John Kelley
Cc: Ross,Charles H - PGPW-5; decoders@xxxxxxxxxxxxxxxx
Subject: Re: grib to netcdf conversion question

On Mon, 12 Feb 2007, John Kelley wrote:

Mr. Ross,

Are you dealing with GRIB or GRIB2 GFS files?

Sincerely,
John Kelley
NOAA/National Ocean Service

Hello all,


I'm trying to convert model grib files into GFE/IFPS compatible file
formats using the Unidata Converter suite.  So far I'm having no luck a

nd

am seeking input from anyone who may be able to help.


Here's what I've done so far...


1.  I'm using a GFS grib file for input.


2.  Create a .cdl file:

        $ gribtocdl -v -g awips.tbl  2007021212_gfs.grib >
gfs_2007021212.cdl


        * I'm using a awips.tbl file that I found while browsing the
unidata archives


3.  Create the nc file:

        $ gribtonc -l - -g awips.tbl gfs_2007021212.cdl awips.nc <
2007021212_gfs.grib

Hi,

if the 2007021212_gfs.grib is in awips format then no Unidata decoder can
convert it to netCDF directly because we don't suppport AWIPS.  Also the
gribtonc decoder is being deprecated for the the Java Grib Libraries. To
use the Java Grib libraries:


One needs to download the toolsUI.jar from the netCDF java page,
http://www.unidata.ucar.edu/software/netcdf-java/

set the classpath and run Grib2Netcdf

#/bin/csh -f

set CP="<yourpathtoo>toolsUI-2.2.18.jar"

java -Xmx512m -classpath $CP ucar.nc2.iosp.grib.Grib2Netcdf INPUT OUTPUT.

NC

Don't forget to add the INPUT grib file and OUTPUT.NC names.

robb...

ps  if the conversion didn't work, you can look at the data with the
ToolUI program by:

java -Xmx512m -classpath $CP ucar.nc2.ui.ToolsUI

        My output here is interesting and may be problematic.  Here is

a

sample:


        -------------

Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mism

atch

Nx: 129 != 65

Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mism

atch

Ny: 85 != 65

Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mism

atch

La1: 7.838 != -20.826

Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mism

atch

Lo1: -141.028 != -150

Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mism

atch

Dx: 95250 != 381000

Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mism

atch

Dy: 95250 != 381000

Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mism

atch

Nx: 129 != 65

Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mism

atch

Ny: 85 != 65

Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mism

atch

La1: 7.838 != -20.826

Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mism

atch

Lo1: -141.028 != -150

Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mism

atch

Dx: 95250 != 381000

Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mism

atch

Dy: 95250 != 381000

Feb 12 21:37:59 gribtonc[13996]: YUHD85 KWBC 121200, awips.nc nav. mism

atch

Nx: 129 != 65


-------------


4.  Even though I'm getting hundreds (thousands) of mismatch statements

I

do get a large .nc file.


From there I'm tried to put it into my designated input directory in th

e

GFE/IFPS but do not see it available when I run the program.


Obviously I'm doing something wrong.


Can anyone out there help me?   Thanks in advance for any
comments/suggestions, etc, I really appreciate it!


-Charles


-------------------


Charles Ross

Meteorologist

Bonneville Power Administration

905 NE 11th Ave.
Portland , OR 97232


503-230-3159


cxross@xxxxxxx

• References:
  • RE: grib to netcdf conversion question
    • From: Ross,Charles H - PGPW-5