Map Projections
• Since spheres and ellipsoids are not developable, distortions must occur.
• Note that the transformation is from three to two dimensions, and that there is no vertical axis in the plane.
Associate points on the surface of an ERM with points on an X-Y plane – or more formally ...
A map projection is a mathematical transformation from a three dimensional ellipsoidal or spherical ERM surface onto a two dimensional plane.