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20030820: imar2gm.f fouled up in 5.6.K again

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  • Subject: 20030820: imar2gm.f fouled up in 5.6.K again
  • Date: Thu, 11 Sep 2003 09:45:24 -0600
David,

I have your changes below, and the ncolor problem you reported too
for reconciliation with code from NCEP.

Thanks,

Steve Chiswell





>From: David Ovens <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200308202013.h7KKDpLd001787

>Steve,
>
>Somehow the re vs RADIUS foul up reappeared in 5.6.K in
>gempak/osurce/gemlib/im/imar2gm.f (5.6.J and 5.6.H were just missing
>the re formulation in the TANC section).
>
>So, 
>
>  ELSE IF  ( navtyp .eq. 'MERC' )  THEN
>C
>C*    Compute lat/lon of the lower-left corner.
>C
>    dxp   = 1. - rxp
>    dyp   = 1. - ryp
>    rm    = dx * dyp
>    rcos  = RADIUS * COS ( phi0r )
>            ^^^^^^
>should be 
>    rcos  = re * COS ( phi0r )
>
>and
>  ELSE IF  ( navtyp .eq. 'LAMB' )  THEN
>C
>C*    Standard latitude #1
>C
>    std1 = stdlat
>C
>
>should be
>  ELSE IF  ( navtyp .eq. 'LAMB' )  THEN
>C
>C*    Earth Radius is ianav(8)
>C
>    re = ianav ( 8 )
>    if (re .le. 6200000.) re = RADIUS
>C
>C*    Standard latitude #1
>C
>    std1 = stdlat
>
>and ( **NOTE** 2 places, in navtyp 'LAMB' and navtyp 'TANC')
>    dxp = 1. - rxp
>    dyp = 1. - ryp
>    rm  = dx * SQRT ( dxp * dxp + dyp * dyp )
>    tmp = ccone / ( RADIUS * SIN ( psi1 ) ) 
>                    ^^^^^^
>should be
>    dxp = 1. - rxp
>    dyp = 1. - ryp
>    rm  = dx * SQRT ( dxp * dxp + dyp * dyp )
>    tmp = ccone / ( re * SIN ( psi1 ) ) 
>
>Also, I think the radius of the earth for 'TANC' is in ianav(7) and is
>already defined at line 195, but you might want to check to see if it
>is in ianav(8).  I don't use that projection in any McIdas files, so I
>am not quite sure.
>
>Without these corrections, our topographic maps do not line up with
>the map database.  Please patch the distribution.
>
>Thanks,
>
>David
>-- 
>
>David Ovens            e-mail: address@hidden
>(206) 685-8108          plan: Real-time MM5 forecasting for Pacific Northwest
>Research Meteorologist
>Dept of Atmospheric Sciences, Box 351640
>University of Washington 
>Seattle, WA  98195
>