Grid definition - Mercator

      Octet
      No.
      Contents
      7-8Ni - number of points along a parallel
      9-10Nj - number of points along a meridian
      11-13La1 - latitude of first grid point
      14-16Lo1 - longitude of first grid point
      17Resolution and component flags (see Code table 7)
      18-20La2 - latitude of last grid point
      21-23Lo2 - longitude of last grid point
      24-26Latin - latitude(s) at which the Mercator projection cylinder intersects the Earth
      27Set to zero (reserved)
      28Scanning mode (flags - see Code table 8)
      29-31Di - longitudinal direction grid length (see Note 2)
      32-34Dj - latitudinal direction grid length (see Note 2)
      35-42Set to zero (reserved)



      NOTES:

      1. Latitude and longitude are in millidegrees (thousandths of a degree).

      2. Grid lengths are in units of meters, at the parallel specified by Latin.

      3. Latitude values are limited to the range 0-90000; bit 1 is set to 1 to indicate south latitude.

      4. Longitude values are limited to the range 0-360000; bit 1 is set to 1 to indicate west longitude.

      5. The latitude and longitude of the last grid point from the first grid point should always be given.

      6. Where items are not given, the appropriate octet(s) should have all bits set to 1, the "missing" indicator.

      7. The first and last grid points may not necessarily correspond to the first and last data points, respectively, if the bit-map section is used.



      Back to Top