The mathematical transformation of a three dimensional world to a two dimensional plane is referred to as a map projection. There are various different categories of projections. These differ in what is preserved such as angles or distance. However, a similarity found in all projections is the ability to portray the discrepancies that occur as a natural result of transforming the world onto paper or a computer screen.
Conformal map projections aim to preserve angles. Mercator and Stereographic projections are two examples of a conformal map. I noticed that my two conformal maps differed in approximately 3,000 miles when measuring the distance between DC and Kabul. This is yet another consequence of map projections that geographers must keep in mind.
Equal area map projections, on the other hand, seek to preserve area. Hammer and Sinusoidal projections are certain types of equal area maps. When measuring the distance between the two capital cities of America and Afghanistan, I noticed that the results were quite similar for both maps, with only a variance of 200 miles.
Lastly. equidistant map projections aim to preserve distance from a standard point. Examples of this category of map projection are Plate Carree and Equidistant Conic maps. Once again, similar to the discrepancies found in the Conformal maps, the distance between DC and Kabul varied substantially. A difference of around 3,000 miles was found in the two maps.
These distortions and discrepancies highlight the very pitfalls of projecting the 3-D world onto a 2-D surface. However, a certain aspect, may it be angles, area, or distance, must be compromised in one way or the other. This is the reality faced by many a cartographer, traveler, or geographer.
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