|Dr. Hartnell's Nutty the A.D.D. Squirrel||
Do people still use these things?
A map is a representation of a place. In order to be perfectly free from distortions, a map must have a spherical surface. A map of this kind is known as a globe. But since globes don't fit well in our glove compartments (trust Dr. Hartnell on this one), we need flat maps. However, flat maps cannot accurately represent the rounded surface of the earth.
Maps are called projections because cartographers (mapmakers) have to project a 3-D surface onto a 2-D map. Since a map is a 2-D representation of a 3-D world, compromises must be made in accuracy (like size), and some information gets lost. It'd sort of be like having someone trace your shadow to try to get an accurate reading of your height. Sure, the area traced around your feet would be spot on, but the rest of your shadow (especially based on the sun's angle) would most likely be waaaay off. (Yea. Face it. You're short.)
There are three map types:
* Planar: Set an illuminated globe on paper and trace the areas shining through. The map you get is accurate at the poles but distorted by the Equator.
* Cylindrical: Slide a paper cylinder over an illuminated globe and trace the areas shining through. The map you get is accurate by the Equator but distorted by the poles.
* Conic: Put a paper cone over an illuminated globe and trace the areas shining through. The map you get is accurate for areas touching the cone but distorted elsewhere.
The most famous cylindrical map is the Mercator map [pictured left].
Made by Gerardus Mercator in 1569, it is the "map of choice" for American schools, newscasters, seafarers, and pilots. (Yup. Pilots use this. Let's just hope you're not flying to Greenland anytime soon. Don't understand what I mean? Keep reading...)
However, like any true cylindrical projection, the Mercator map preserves the shape of continents and countries but distorts the size of areas further from the Equator.
Horribly distorted, Antarctica is usually cropped from the bottom of Mercator maps. (That's right Antarctica. Either get a population or get cropped. 'Dem the rules.)
Another key distortion of the Mercator map is known as the "Greenland Problem".
With this distortion,
Greenland is depicted as being the same size as Africa... even though
Africa is 14 times larger than Greenland in real life.