W3FB09

The W3FB09 routine converts a location on earth given in
           an i,j coordinate system overlaid on a mercator 
           map projection to the coordinate system of
           latitude/longitude.

USAGE:  CALL W3FB09 (XI,XJ,ALAT1,ALON1,ALATIN,DX,ALAT,ALON)

   Input argument list:
     XI       - I COORDINATE OF THE POINT
     XJ       - J COORDINATE OF THE POINT; BOTH REAL*4
     ALAT1    - LATITUDE  OF LOWER LEFT CORNER OF GRID (POINT (1,1))
     ALON1    - LONGITUDE OF LOWER LEFT CORNER OF GRID (POINT (1,1))
                ALL REAL*4
     ALATIN   - THE LATITUDE AT WHICH THE MERCATOR CYLINDER
                INTERSECTS THE EARTH
     DX       - MESH LENGTH OF GRID IN METERS AT ALATIN

   Output argument list:
     ALAT     - LATITUDE IN DEGREES (NEGATIVE IN SOUTHERN HEMIS)
     ALON     - EAST LONGITUDE IN DEGREES, REAL*4
              - OF THE POINT SPECIFIED BY (I,J)

REMARKS:
        Formulae and notation loosely based on Hoke, Hayes,
        and Renninger's " map projections and grid systems...", 
        MARCH 1981 AFGWC/TN-79/003

 
W3lib.tar Library contains Fortran 90 decoder/encoder routines for GRIB edition 1. (Fortran90)
Date posted: 2/22/2007