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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 and 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. mismatch Nx: 129 != 65
Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mismatch Ny: 85 != 65
Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mismatch La1: 7.838 != -20.826
Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mismatch Lo1: -141.028 != -150
Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mismatch Dx: 95250 != 381000
Feb 12 21:37:59 gribtonc[13996]: YHHD99 KWBC 121200, awips.nc nav. mismatch Dy: 95250 != 381000
Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mismatch Nx: 129 != 65
Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mismatch Ny: 85 != 65
Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mismatch La1: 7.838 != -20.826
Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mismatch Lo1: -141.028 != -150
Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mismatch Dx: 95250 != 381000
Feb 12 21:37:59 gribtonc[13996]: YHHD30 KWBC 121200, awips.nc nav. mismatch Dy: 95250 != 381000
Feb 12 21:37:59 gribtonc[13996]: YUHD85 KWBC 121200, awips.nc nav. mismatch 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 the 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


address@hidden






===============================================================================
Robb Kambic                                Unidata Program Center
Software Engineer III                      Univ. Corp for Atmospheric Research
address@hidden             WWW: http://www.unidata.ucar.edu/
===============================================================================