There have been a few map posts that have popped up in my feed recently showing the actual size relative to how they are portrayed in a map. For instance countries in the north like Canada and Russia appear much bigger compared to their actual size, but Africa was almost perfectly represented.
In: Technology
[This does a nice job of showing how different projections produce different looking maps.](https://www.youtube.com/watch?v=D3tdW9l1690)
The problem with a map is that the world is round, but a map is flat. So you have to do some kind of image distortion or [strange map shapes](https://gisgeography.com/map-projections/) in order to draw a map of the world on a flat piece of paper on a computer screen.
Most distortions tend to be at their worst near the north and south pole, and Canada and Russia are both pretty close to the north pole. Africa has the equator going through it which means it usually has the least distortion.
The explanation I know, which only covers maps in the US, is to make the United States the most prominently displayed area. This is why Greenland (maybe Iceland can’t remember) is drastically oversized. Normal size would put the US near the top. Making it longer puts the US in the middle. I’m sure most if not all inaccuracies in maps serve some kind of purpose similar to this.
TL:DR – to make the country the map is made in look more important.
Edited for typos
Not sure about the exact reason. I do know it has to do with the earth being round therefore changing a land’s actual size visually when portrayed on a map.
To make them fit. Like Alaska is the size of 1/3 of the us. Alaska is much bigger than Greenland. Australia is bigger. Sizing just become weird when you make it flat. Greenland looks really stretched out, etc
You can flatten out the surface of a sphere on a square surface. Try peeling an orange and see what happens with is when you try to flatten it. It will get deformed and it will tear.
So when you make a flat map you have to compromise.
Relevant factors on a map Area, Shape, Direction, Bearing, Distance. If you try to represent one better other will get worse. So a map projection is a compromise and there is multiple projections.
The only way to have a true shape is on a sphere. So a globe you can purchase will have all parameters above correct. Any flat paper map will have something that is not correct.
One common projection is the [Mercator_projection](https://en.wikipedia.org/wiki/Mercator_projection#/media/File:Mercator_projection_Square.JPG) . It has bee used since 1569 and what is preserved is being. So if you sail at a constant bearing you move the straight line on the map. This is why it was used because it is very useful when you sail ships.
The drawback is that area is not preserved and the distortion is larger the close you are to the poles.
Because the common historical use it is still the most used projection. On the internet, a slight modification Web Mercator projection is used. Google maps and almost all other online web services use it
There are other map projections that preserve areas like the [Lambert cylindrical equal-area projection](https://en.wikipedia.org/wiki/Lambert_cylindrical_equal-area_projection#/media/File:Lambert_cylindrical_equal-area_projection_SW.jpg) . But is distorts the shapes of land and a constant bearing is no longer a straight line.
So maps can preserver areas but then you sacrifice other things. So you can select what you want to used. In practice, most use Mercator because it is common and people in general expect a map to look like that.
Latest Answers