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Re: Fw: almost there...

Hi Chiz,

I've tested pretty much everything, and its working perfectly now!
Thanks again for your help!

Best Regards,
___________________________
        Guilherme O. Chagas
                address@hidden

On 25 Oct 2005 13:15:59 -0600, Steve Chiswell wrote
> Guilherme,
> 
> I've attached a modified dcgrib2 (linux) binary with updates for
> the SCC. Previously, only the LCC string was changed to SCC. 
> This version modifies the flag interpretation for computing the
> coordinate transformations from the secant cone.
> 
> Can you test this out, and if differences still exist versus your GRADS
> output, would you send the grib data that the GRADS plot was created
> with for direct comparison. The MM5 data I have from you was a May 25
> run instead of the Sept data you plotted in the attachment.
> 
> Steve Chiswell
> Unidata User Support
> 
> On Fri, 2005-10-07 at 19:07, Guilherme O. Chagas wrote:
> > Hi everyone,
> > this is a forward of an old email, discussing a problem encountered during 
> > the
> > conversion of a MM5 grib with a SCC (southern hemisphere) projection 
> > centered
> > over Rio de Janeiro, Brazil. The whole problem is described below!
> > 
> > 
> > ---------- Forwarded Message -----------
> > From: "Guilherme O. Chagas" <address@hidden>
> > To: address@hidden
> > Sent: Thu, 15 Sep 2005 16:09:47 -0200
> > Subject: almost there... 
> > 
> > Hi Steve,
> > well, back with the MM5 SCC conversion that we discussed in the workshop...
> > I've got to actually decode the grib here (like we did before), but it
> > occurred to me that there's still something wrong with the output... Take a
> > look at the picture attached, comparing the GrADS output (left) with GEMPAK
> > (right). The red circles indicate an island as a reference point, and, as 
> > you
> > can see, the plot is pretty deviated. The UR corner is misplaced by a few
degrees.
> > During the conversion, theres this warning in the log (using -v 4):
> > [10542] 050915/1429[DCGRIB 4] Warning, SCC grid with unexpected GDS.flag2 0
> > I looked at the source code, and there's a subroutine that "gathers" the 
> > grid
> > size - dcogfil.c . I tried to change it, in order to set the lat and lon
> > values manually, but it didn't work out the way I expected (I assumed that
> > another routine is also working with lat and lon variables).
> > Can I set the grid size manually when using dcgrib2?
> > I'll try to find another SCC model output (WRF perhaps) to see if the same
> > thing happens, I'll keep you posted!
> > 
> > Best Regards,
> > ___________________________
> >         Guilherme O. Chagas
> >                 address@hidden
> > ------- End of Forwarded Message -------
> > 
> > 
> > ___________________________
> >         Guilherme O. Chagas
> >                 address@hidden
> >