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19990309: grdinfo and MRF grids

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  • Subject: 19990309: grdinfo and MRF grids
  • Date: Fri, 12 Mar 1999 13:28:38 -0700
>From: weather <address@hidden>
>Organization: NMSU/NSBF
>Keywords: 199903090301.UAA21398 McIDAS GRID MRF

Robert,

Sorry I didn't get to this sooner.

>I have figured out a way to create text forecasts soundings using grdinfo
>and sed.  The problem I discovered is in the MRF.  The spacing of the
>grid points for Z is much greater than for T or other variables and
>specifically SPD and DIR which I am producing.

It is possible that you are looking at Z in one projection and the
other parameters in a different projection?

>I cannot determine 
>from the documentation if this is the way it should be.

If the grids are the same (meaning same projection), then the spacing
should be the same for the MRF.

>The command below
>run from DERIVE=SPD UNIT=KT produces many more grid points.  I don't
>have this problem with the ETA or Alaskan ETA.
>
>
>GRDINFO RTGRIDS/MRF LIST TIME=12 LEV=850 PARAM=Z UNIT=FT FORMAT=I7.2 LAT=63 68
>LON=143 150                             
>Listing data from Z    Grid at 850 MB   from MRF  at 120000 UTC on 1999067    
>                          from dataset: RTGRIDS/MRF                           
> Column    Row    Latitude    Longitude    Value         Units  Level  Param  
>    28      38      64.459     150.000    4241            FT   850  MB   Z    
>    29      38      66.803     143.660    4347            FT   850  MB   Z    
>GRDINFO Done, Number of grids listed=1                                        
>GRDINFO - done 

I ran the exact same invocation of GRDINFO and got the same kind of results:

GRDINFO RTGRIDS/MRF LIST TIME=12 LEV=850 PARAM=Z UNIT=FT FORMAT=I7.2 LAT=63 68 
LON=143 150
Listing data from Z    Grid at 850 MB   from MRF  at 120000 UTC on 1999071
                          from dataset: RTGRIDS/MRF
    Row    Col    Latitude    Longitude    Value         Units  Level  Param
    38      28      64.459     150.000    3920            FT   850  MB   Z
    38      29      66.803     143.660    4060            FT   850  MB   Z
GRDINFO Done, Number of grids listed=1
GRDINFO - done

I believe that the listing is telling us that the grids are different
since the Column and Row are not the same.

Am I missing something here?

Tom

>From address@hidden  Fri Mar 12 13:56:03 1999
Of course, I forgot!  The projections must be different.  I should really
file the same projections in the same file.

By the way, we received our 333Mhz Sparc from EIS computers.  The
compilers should arrive Monday, it looks pretty darn fast right now,
but we will see how how long it take to compile McIDAS.

Thanks,
Robert