...the use of different Map Projections (WEEK 6 Lab)

Maps make it easy to put the world in our pocket, that is to say, they allow us to put the world as a 2-D model on paper. However, due to the Earth's 3-D curvature, and its various properties, maps could project the world in many different ways, depending on what exactly the map seeks display. Below are two examples per type of map projection, for a total of six examples. The three map projections shown are conformal, equal area, and equidistant. I shall explain below each display what makes the specific types of projection unique, what it is used for, and other general information that may relate.

The first type of map projections are conformal map projections, shown above by the Mercator and Gall Stereographic maps. Conformal maps have the unique quality of preserving local shapes and angles, and are characterized by the way in which parallels and meridians meet in a perpendicular fashion (this characteristic is not found in the other projections, scroll down and see for yourself). Since this type of map tries to maintain 90 degree angles, it simplifies and fails to acknowledge many properties of the Earth, and as such, the location of items on the maps, and distance between them may be skewed. This is seen in the extreme variation in the distance measured between Kabul and Washington D.C. in the Mercator and Gall Stereographic Maps above. Though Conformal maps are not a wise choice to measure distance or to gather reliable statistical information, the flat nature of the maps allows them to display features such as topography, that could not be displayed easily on a rounded map.

Equal Area map projections as shown above by the Boone and Hammer Aitoff maps, are characterized by the maintenance of proportionality among areas on the map in comparison to the areas they represent in real life. Why is this important or useful? What better way to find out than by applying a real life situation? Suppose you are a government official deciding what plot of land is bigger and more capable of building a new school. You would use an equal area map projection to compare the areas of the plots accurately and make the best selection. Equal area maps are a valuable tool used to compare the size of objects featured on a map.

The third map projection to share are equidistant map projections, displayed by the sinusoidal and equidistant conical maps above. Equidistant maps do just as the name suggests; this projection ensures the preservation of distance between any two points. The equidistant projection does this by taking into account the natural curvature of the Earth and its effect on the area between two points. The two equidistant maps have a smaller difference in destination measured between Kabul and Washington D.C. when compared to the variation of values derived from equal area and conformal maps. Equidistant maps are best used for determining distance.

In conclusion, different map projections exhibit different qualities, and are best at portraying different information. With that said, it is great to have the option of so many map projections. It allows the creator of the map to produce a map that will meet the needs of the user, whether it be a government agency needing an equal area map to decide on a location for a military base, or the military needing an equidistant map to plan a test flight of a new jet.