The Myths created by the Mercator Projection

The Mercator Projection is the biggest myth about the Earth that we pass on (often unknowingly) to our children.  OK, I don’t know if it is the biggest but it certainly builds the wrong perception of the globe.

The Mercator projection was originally designed in the mid 1500’s.  A highly useful projection because it kept course lines constant.  A ship’s navigator could plot a course with a straight line from one port to another.  No map projection can keep all features accurate, so the Mercator projection distorts the size and shape of large objects.  Land masses at the Equator appear smaller and land masses at the poles are magnified significantly.

Mercator_projection

A few points lifted from Wikipedia:

  • Greenland takes as much space on the map as Africa, when in reality Africa’s area is 14 times greater and Greenland’s is comparable to Algeria’s alone.
  • Alaska takes as much area on the map as Brazil, when Brazil’s area is nearly five times that of Alaska.
  • Finland appears with a greater north-south extent than India, although India’s is greater.
  • Antarctica appears as the biggest continent, although it is actually the fifth in terms of area.

The Mercator projection is not suited for a general reference world map due to the distortion of the land areas.  However, if I were a certain Island known as the royal seat for a global empire based on exploration and sail, it would be a great projection as my Island would look bigger.

true-size-of-africa

I like to stun people by showing them the true size of Africa.  Here’s a link to another article with some background on the image above: http://www.economist.com/blogs/dailychart/2010/11/cartography.  My young children have become so familiar with the Mercator projection that it took some explaining to get them to realize what happened.  It also mandated my buying a real globe for the house and tearing up an orange to show how real objects don’t flatten well.

From: From J B Krygier at  http://go.owu.edu/~jbkrygie/krygier_html/geog_222/geog_222_lo/geog_222_lo13.html
From: J B Krygier

The Gall-Peters is a better map to show relative sizes of land mass.  If looking at this makes you twitch somewhat; it may be remind your of the last time you looked into a fun house mirror that made your head shrink.

Galls Peters Projection

 

It also meets the unwritten rule that wall maps should be perfectly square.  If you don’t need a square map to represent a spherical world, you can use an equal-area map like the Mollweide projection.

Mollweide_projection

No matter which map you choose. Understand what is was meant to show.  Help break the myths created by using the wrong map for the wrong purpose.

2 thoughts on “The Myths created by the Mercator Projection”

Comments are closed.