Week 6 LAB

For this week's lab, the mapping of six different types of globe projections revealed the attributes and limitations of three types of projections: conformal, equidistant, and equal area. Two examples of each of the three major types of projections are posted to provide examples of variances within the specific types of projections.

The first set of maps, Mercator and Stereographic, are examples of conformal projections.  These projections are useful in that they preserve all the angles within a localized area. Specifically, the Mercator projection is used commonly, despite the severe area distortion of land masses like Africa and Greenland, making the two seem like they are roughly similar in size, when they are not in reality.  Although right angles may be preserved in conformal projections, the occurrence of such area distortions are a significal pitfall of these particular map projections.

In the second set of maps, Equidistant Conic and Equidistant Cylindrical, are specific examples of equidistant map projections.  In these projections, angles and area may not be preserved on a map, but the distance from a particular point or set of points are preserved.  This may prove especially useful when the primary goal of a map projection is to ensure that point distances are maintained above all else (as in this lab where the distance between two cities, Kabul and Washington D.C., is a key component).

The final set of maps, Cylindrical Equal Area and Sinusoidal, are equal area projections.  Unlike the previous two projections, these maps work to preserve global areas. However, there is a trade off as angles and distances may be distorted in various places on the map.  The three projections all trade off on accuracy on issues of distance, area preservation, and angle preservation.  However, if one is familiar with the potential benefits and inaccuracies that come with each particular projection, one can pick a projection that best accomplishes whatever goal the map is meant to achieve.