Because the Earth is spherical and maps are flat, so perspective isn't correct.

Hi Lauren,

Mapping the Earth always presents something of a problem and that’s because the Earth is a three-dimensional sphere (technically an oblate spheroid) whereas a map is a two-dimensional projection.

If you think of the lines of longitude on a globe, they converge at the geographic north and south poles. But when represented on a map the lines are opened out such that they become parallel and are as wide at the Equator as they are at the poles

The conventional two-dimensional map, known as a Mercator Projection, therefore distorts the size of land-masses by enlarging them, the further from the horizontal centre of the map (normally where the Equator would be represented) the greater the distortion and enlargement.

Using Greenland and Australia as examples, on a conventional map Greenland will appear considerably larger than Australia, as indicated here:

http://faculty.ccc.edu/jtassin/geology20...

But in reality Australia is three times the size, as shown here:

http://en.wikipedia.org/wiki/File:Austra...

The only way to get around this is to create a map which doesn’t distort the shape of the Earth and for that a type of map known as an Interrupted Sinusoidal Projection could be used. This shows the countries in their true sizes but you end up with a map that looks like this:

http://www.progonos.com/furuti/MapProj/D...

Another way to look at it would be to imagine you’re giving someone a football as a gift and you want to wrap it up for them. For whatever reason you decide to use a map of the world to gift-wrap the present. If you used the sinusoidal map and cut around the edges, you’d be able to wrap the football neatly with no overlaps and all of the ball covered. If you used a normal map (a Mercator type) you’d have lots of excess paper that you’d have to cut off, scrunch up of fold over itself.

I don’t know if I’ve explained that in a way that makes sense, I hope it does.

You never studied maps in elementary school? Wow. A square map is not proportional. They are stretched at the top and the bottom

you would need a globe