Map Projections essays

Map Projections essays Map Projection can be defined as the spatial relationship between features on the earths surface and their representation on a flat map. This compares and transforms the earths 3-D terrain to a flat 2-D surface. Map projections are created in a two step process. The first step is to assume that the earth has been mapped on a reference globe to fit the chosen scale for the flat map. The second step is to transform, mathematically, the reference globes surface onto a flat surface, point by point. When transferring the spherical surface to a flat plane, distortions will result. Area, Angle, Distance and Direction distortions are the most commonly occurring and are the ones that need to be fixed during transformation. In map projections, it is best to see what type of projections will be best used. Conformal projections are one type of map projection that cal be used. Conformal projections consist of Mercator, Transverse Mercator, Lamberts conformal conic projection with two standard parallels and conformal stereographic projections. Mercator projections are the probably the most famous map projection ever devised. Equal Area Projection is another form of Map Projection used; however, the choice to use an equal area projection is based on two processes. It is important to consider the size of the region involved and the distribution of angular deformation. In considering when Equal area projection to use, one might choose from Albers Equal are or Lamberts Equal area projection, both which are widely used today. Besides Equal Area Projections, there are World Equal-Area Projections. These can be consisted of cylindrical equal-area, sinusoidal, Mollweide or Goodes projection. Groups of Projection might be including Azimuthal, orthographic, simple conic, polyconic or space oblique Mercator projection. ...