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Re: 20050729: Fw: problems converting MM5 to Gempak

Steve,
I ran the last dcgrib2 compilation, and the results are correct now, as far as I know. I still have to check with grads, but I have no reasons to believe that something went wrong. I'll be changing the source code of the process that generated the grib to use the correct flag for SCC on bit7 of octet 27. I'll let you know if anything went wrong. Best Regards, 
___________________________
        Guilherme O. Chagas
                address@hidden

On Fri, 29 Jul 2005, Steve Chiswell wrote:


Guilherme,

I ran dcgrib2 with the "-v 4" option to output very verbose information.

When decoding your file, it shows that:
GDS byte       27 (flag2)         = 0

I had expected bit7 of octet 27 to be "1", per:
http://www.nco.ncep.noaa.gov/pmb/docs/on388/tabled.html
Euther I'm interpreting the docs wrong for the meaning of the
projection point, or the MM5 grib output isn't setting the appropriate
bit.

I recompiled the code with an independent check for hemisphere to
name projection SCC for southern hemisphere, but the computation
of the grid points internally does use that flag2 value, so I'm
not sure if the result will be correct. You can compare with your other
software and let me know.

Steve



On Fri, 2005-07-29 at 13:55, Guilherme O. Chagas wrote:

mm5 model output attached

Guilherme
On 29 Jul 2005 11:32:08 -0600, Steve Chiswell wrote

dcgrib2 for linux attached

Chiz

On Wed, 2005-06-15 at 08:43, Guilherme O. Chagas wrote:

Sorry if you've received this message before, but I haven't received any
replies yet.
---------- Forwarded Message -----------
From: "Guilherme O. Chagas" <address@hidden>
To: address@hidden
Cc: address@hidden
Sent: Mon, 30 May 2005 16:11:54 -0200
Subject: problems converting MM5 to Gempak

Hi Steve,

I've been working on the conversion of a MM5 operational run to Gempak, also
looking forward it's distribution over IDD-Brazil. DCGRIB2 converted without
errors the original grib, however both nmap2 and gdplot were uncapable of
plotting any requested variable. They've displayed this error message:

 [GEMPLT -16]  NIPBND - Invalid projection bounds.
 [GEMPLT -16]  NIPBND - Invalid projection bounds.
 [DG -37]  No reference grid navigation is set in GPLT.

according to gdinfo, this is the configuration of the grid:

 GRID NAVIGATION:
     PROJECTION:          LCC
     ANGLES:               -20.0   -43.0   -26.0
     GRID SIZE:           50  50
     LL CORNER:             -27.33    -47.96
     UR CORNER:             -20.99    -41.15
 GRID ANALYSIS BLOCK:
      UNKNOWN ANALYSIS TYPE
 Number of grids in file:    13
 Maximum number of grids in file:  29999
  NUM       TIME1              TIME2           LEVL1 LEVL2  VCORD PARM
    3     050525/0000F006                          0         HGHT PRESHAG
 Parameters requested: GDFILE,LSTALL,OUTPUT,GDATTIM,GLEVEL,GVCORD,GFUNC.

The grid is located over Rio de Janeiro, Brazil, and, for testing purposes,
only one level (1000) and one time were used.
I've also generated the conversion tables and, as far as I know, they're
working correctly. Any ideas on where my error might be?

Best Regards,
_______________________     ______________________________________________
    Guilherme O. Chagas          Laboratório de Prognósticos em Mesoescala
            address@hidden             Universidade Federal do Rio de Janeiro



___________________________
        Guilherme O. Chagas
                address@hidden