This is a variation of the standard Transverse Mercator projection that is provided for the definition of coordinate systems used in specific counties in the U.S. states of Minnesota and Wisconsin. Within a specific county in one of these states, the ellipsoid must be expanded by an additional amount to account for the average elevation within that county. In the case of a Wisconsin county, the ellipsoid must also be adjusted based on the average geoid height for that county. For Minnesota counties, the average geoid height should be set to zero.
The "Transverse Mercator Extended" projection has the following parameters:
-
Longitude of the Central Meridian
-
Latitude of the Origin of the Projection
-
Scale Reduction Factor at the Center of the Projection
-
False Easting
-
False Northing
-
Average Elevation (Minnesota and Wisconsin)
-
Average Geoid Height (Wisconsin only)