05/09/2026
The UN just changed the world map! What do we do now?
Nothing. At least not with our topo maps.
This week the UN General Assembly backed the Equal Earth projection as a better way of representing the world than the familiar Mercator projection.
The problem is simple: you can’t flatten a globe without distorting something.
Mercator greatly exaggerates the size of places towards the poles. Australia would look much bigger if it was moved to Greenland’s location on a Mercator map.
Equal Earth is an equal-area projection, so countries and continents appear in their correct relative sizes.
But what about our topo maps?
No change.
For bushwalking in Australia, we commonly use the Map Grid of Australia (MGA), based on the Universal Transverse Mercator (UTM) system.
Instead of trying to flatten the entire world onto one map, UTM divides it into 60 narrow zones, each 6° of longitude wide. Each zone gets its own projection and grid.
That’s what gives us the eastings and northings measured in metres that we use for grid references. Most of Victoria sits in UTM Zone 55.
ACTIVITY
Find a Mercator world map.
Ask your scouts:
Which is bigger – Greenland or Australia?
Which is bigger – Greenland or Africa?
Compare it with an Equal Earth map or a globe.
Why are they different?
Then pull out your local topo map and find the UTM zone, eastings, northings and grid squares.
Remember, there is no perfect flat map of the Earth.
Different maps are designed for different jobs. Equal Earth preserves relative area. Mercator preserves angles and makes compass bearings easy to plot. UTM minimises distortion within each zone, making it ideal for local navigation.
OAS Bushwalking 6 asks us to research 5 types of maps and use 3 different types of maps in an activity. You could use this announcement to start a discussion about the different kinds of maps we use for different purposes and their pros and cons.
