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imar2gm.f fouled up in 5.6.K again

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  • Subject: imar2gm.f fouled up in 5.6.K again
  • Date: Wed, 20 Aug 2003 13:13:45 -0700 (PDT)
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