Map Projections What is a map projection A

Map Projections

What is a map projection? A way of viewing the 3 -dimensional world 2 -dimensionally ◦ Ex. If you were to draw the world on an orange and try and lay it flat what would happen? Distortion � It is impossible to draw the world without distortion � Map makers attempt to minimize different distortions based on the purpose of their map

Distortion 4 types of distortion on maps: ◦ ◦ Size Shape Distance Direction

BONUS What does a cartographer do? Create maps Give maps a purpose

Compare the following 2 maps � What are their similarities/differences? � Where do you see distortion?

Mercator Projection

Robinson Projection

Mercator Projection Lines of constant bearing Use: marine navigation – breakthrough in 16 th century nautical cartography Distortion: size – greatest at poles

Robinson Projection � Compromise- conformal neither equal-area or Use: previously used as the standard projection for world maps made by the National Geographic Society Distortion – severe closest to poles and quickly declines moving away from them

Mercator Projection

Robinson Projection

Equal Area Projection

Equal Area Projection Goal: minimizes the size distortion by drawing all countries proportionately to each other Use: to view/compare/analyse the world by land mass

Winkel Triple Projection

Winkel Tripel Projection Goal: to minimize all types of distortion: size, shape, direction and distance Use: replaced the Robinson projection as the standard projection for world maps made by the National Geographic Society

Summary � When reading a map it is important to be aware of the projection. � There is no perfect projection and there aren’t necessarily any bad ones either — just bad uses of them.

Lightning Review

Map makers could also be called a ______. ◦ ◦ Geologist Geophysicist Geographer Cartographer

_____ is an inevitable result of making the Distortion 3 -dimensional world 2 -dimensions • The 4 types of distortion that cartographers try to minimize are: • • Shape Size Distance Direction

The projection that shows lines of constant bearing and was a breakthrough for navigation is called: • Mercator • Equal Area • Winkel Triple

The projection that is currently used for world maps and is the best compromise between all types of distortion is: • Mercator • Equal Area • Winkel Triple

This projection minimizes the size distortion by mapping countries proportionately to each other • Mercator • Equal Area • Winkel Triple