Lab #5

Map projections are important when you are looking for places or calculating your route for a trip. Since there is not one perfect universal map for all occasion. Also all maps have some sort of distortion, which makes you have to think and pick a map projection that's best fits for your circumstance. When deciding on a map projection you want to consider the aspect and the properties. The aspect is the basic layout you want either cylindrical, conic, or azimuthal. Then you can classify the map projection into properties area, which are different kinds of distortion to the area. These areas can have conformal, or equal-area or equidistant. When deciding on map projection you have to consider what part (distant, shapes, areas) doesn’t matter or does matter during distortion.

Conformal is known for preserving map locally. Meridians (lines of longitude) and parallels (lines of latitude) intersect at right angles. Conformal map preserve shape. The Mercator Map is widely used as world map. Mercator does hold distortion when you look at the map. For example, when you are looking at Greenland and Africa you notice that they are both about the same size, but you know Greenland is not big as Africa. In the Gall Stereographic map you notice at the standard parallels that there is no distortion, but as you increase away from the parallels its slowly distort more and more.

Equal-Area preserves an area on a map. This mean every area on the world is equal area to each other. Bonne's projection map has the least distortion near standard parallel at the equator and standard meridian, but as you move away it distorts. Equal-Area Cylindrical projection has straight lines. All meridian are equally spaced while the parallel are not equally spaced between each other. The higher the degree location you move away from the standard parallel the more distortion occurs.

Equidistant maps show you the true distances from center of the projection. Equidistant map do have flaws too and can be misleading. For example, the Azimuthal Equidistant projection map shows us Washington D.C. as the center, so every time you find the distant from Washington D.C. to any other location it is true distant. But lets say you want to find the distant from Los Angeles to New York, it will provide you misleading distances. This is cause by Los Angeles not being centered on the map. Equidistant Cylindrical projection map are called simple map form. Most people like the Equidistant Cylindrical map because all coordinate lines are straight and parallel lines cross meridians at right angles. Also the scale is consistent throughout the map.

As you can see that each map type are distorted in different ways. There will not be perfect map projection for all situations. Each map with have advantages and disadvantage on shape, distance, area, and direction.