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20000810: Using gfunc = vor(wnd)

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  • Subject: 20000810: Using gfunc = vor(wnd)
  • Date: Thu, 10 Aug 2000 16:02:21 -0600
Chris,
The VORWND name is the internam name that gempak creates when it
performes the calculation (and will use that as the title, unless you
give it a more descriptive TITLE.

The problem I believe you have is that you have SCALE=0 while vorticity values
are typically on the order of 10^-5. I suggest you set SCALE=999 or
SCALE= , rather than SCALE=0 so that gempak will appropriately scale the
data values for CINT to contour. With SCALE=0, you probably have
vcalues like MAX=0.00020 MIN=-0.00010, so the output just shows 0.00.

Steve Chiswell
Unidata User Support




>From: address@hidden (Chris Hennon)
>Organization: UCAR/Unidata
>Keywords: 200008102005.e7AK5YT16451

>Steve -
>
>I'm trying to produce a relative vorticity map.  In my gempak grid file
>(vorticity.grd) I have these two grids:
>
>289     950812/0000                            850         PRES UWND        
>290     950812/0000                            850         PRES VWND        
>
>My GDCNTR input looks like:
>
> GDATTIM   Grid date/time                    950812/0000
> GLEVEL    Grid level                        850
> GVCORD    Grid vertical coordinate          PRES
> GFUNC     Scalar grid                       vor(wnd)
> GDFILE    Grid file                         vorticity.grd
>
>etc.....
>
>When I run it, gempak interprets vor(wnd) as the parm VORWND and therefore
>doesn't plot anything:
>
> GEMPAK-GDCNTR>r
>
> Grid file: vorticity.grd                                                     
>       
> GRID IDENTIFIER: 
>    TIME1             TIME2         LEVL1 LEVL2   VCORD PARM
>950812/0000                           850          PRES VORWND      
>
> GAREA:     dset
>SCALE:  0
>
> MINIMUM AND MAXIMUM VALUES     0.00     0.00
>
>
>Am I doing something obviously wrong?  Thanks.
>
>Chris
>
>
>================================================
>| Chris Hennon        Ohio State University   |
>| Tropical Meteorology      address@hidden   |
>|                                              |
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