Assignment #5 - Projections in ArcGIS

Mercator (Conformal)

Albers Equal Area Conic

Cylindrical Equal Area

Equidistant Conic

Equidistant Cylindrical

Lambert Conformal Conic

Map projections are needed for their different capabilities. One is convenience. When a map user needs only specific information, then a certain map projection is helpful. If a map user needs a map with a good distance measure, then they can use an equidistant map. If he or she needs a map for the equatorial region, he or she can use a Universal Transverse Mercator map. With all the map projections, choosing the right one will help people with whatever they need their map to relay. However, with map projections, this trait is also its downfall.

Map projections cannot display all of the qualities that a globe can display. One quality is always distorted in map projections. For example, in an equidistant conic projection such as the one above, the shapes of the continents are distorted. However, in this conic projection the distances from place is equal throughout the whole map. The smaller the area of your map, the greater accuracy it has as well. Because a map projection is a two-dimensional palette, it cannot display the qualities and attributes of a curved three-dimensional globe.

Even though there are perils of map projections, there are still many more potentials. Using the correct projection, depending on what one is using the map for, the map projections can be accurate. For example, for a good representation of Europe, a person can use the Mercator map projection (like the one shown above). Another good example is the equidistant conic projection, which many pilots use because of its accuracy in distance.

Using ArcMap to change the different types of map projections helped greatly. Switching easily from projection to projection allowed me to see the different types much faster and more accurately than looking at papers. Map projections are very helpful depending on what you are using it for. There are hundreds of ways to make a map projection based on whether you use conical, cylindrical, planar, etc. Map projections are good instead of carrying a globe everywhere you go.