I would like to propose adding another "Grid mapping" to appendix F.
The /UTM_Zone_Number/ parameter name is taken from FGDC, the optional
ellipsoidal parameters follow Snyder.
Universal Transverse Mercator
grid_mapping_name = universal_transverse_mercator
/Map parameters:/
* UTM_Zone_Number - in range [1,60] (north) or [-1, -60] (south)
* semimajor_axis - radius of the equatorial axis of the ellipsoid in
meters
* inverse_flattening - inverse flattening ratio (eg 297)
/Map coordinates:/ The x (abscissa) and y (ordinate) rectangular
coordinates are identified by the standard_name attribute values
projection_x_coordinate and projection_y_coordinate respectively.
/Notes:/
The Universal Transverse Mercator projection is a special case of the
Transverse Mercator projection using an ellipsoidal earth. The scale
factor (.9996), projection origin latitude (0), and false easting
parameters (50000 m) are all fixed. The central meridian and
false_northing parameters are specified by the UTM zone.
The ellipsoid parameters /semimajor_axis/ and /inverse_flattening /are
optional. If not present, the standard ellipsoid for the given UTM zone
should be used.
Formulas for the mapping and its inverse along with notes on using the
PROJ.4 software package for doing the calcuations may be found at
http://www.remotesensing.org/geotiff/proj_list/transverse_mercator.html
Received on Tue Feb 01 2005 - 16:21:28 GMT
