What different world maps get right – and what they get wrong

Notably, the UN has just pressed the predominant world map to be replaced with one that more accurately reflects the true size of continents like Africa.

Key points

• The now widely applied Mercator map was created in 1569 by Flemish cartographer Gerardus Mercator.
• The Peters world map was designed by German historian Arno Peters in the early 1970s.
• As cartography Professor James Cheshire at University London College explained, its main purpose was to support European sailors navigate the oceans.
• Consequently, the Equal Earth map was initially adopted by 54 members of the African Union, before being adopted by the UN.
• More than 450 years on, Mercator's creation is still the basis for plenty of of the maps we see in classrooms, on TV and online, including Google Maps.

For context, the "Correct the Map" resolution adopted by the General Assembly intends to fix the discrepancy on the Mercator map, in which the African continent is shown as being of similar size to Greenland – even though it is in reality concerning 14 times larger.

It adopted a new map, the Equal Earth projection. It better represents the true sizes of landmasses – but comes with challenges of its own.

There have been plenty of prominent attempts over the years to solve the challenge of accurately representing the surface of a sphere on a flat rectangle, each with its own benefits and drawbacks.

For context, the now widely applied Mercator map was created in 1569 by Flemish cartographer Gerardus Mercator.

"He wanted a straight line to be drawn on a map to look like a straight line in reality if you followed a compass bearing, " he informed the BBC. "That was what it was intended to do, and that's what it does brilliantly well."

To keep those angles correct on a flat map, Mercator had to stretch the grid lines wider as they moved away from the equator toward the poles.

His map accommodates for the curvature of the Earth by making countries near the equator seem much smaller than they are, with countries nearer the poles appearing stretched.

Notably, the distortion is a result of it being impossible to accurately represent the surface of a globe on a two-dimensional chart.

As we instinctively view bigger things as more significant, but critics of the Mercator map say there is a psychological effect to viewing some places as smaller than they actually are and others as larger.

For Kenyan geographer Kioko Muendo, this has implicitly downplayed Africa's vast resources, population and investment opportunities.

"Maps are more than just guides for travellers – they shape how regions are perceived politically and economically, " he informed the BBC.

Meanwhile, the Equal Earth map intends to address this challenge with the Mercator projection.

It was developed by a team of cartographers in 2018 to present the size and shape of landmasses more accurately.

But to do this, it sacrifices the straight lines that created the Mercator projection perfect for navigating with – and it cannot be employed for measuring the true distance between different places.

"You can preserve area, or you can preserve shape, or you can preserve distance and direction, but not everything at once perfectly, because otherwise you'd be back to a sphere, " Cheshire remarked.

In practice, the Peters world map was designed by German historian Arno Peters in the early 1970s. The rectangular map is based on the projection first described by Scottish cartographer James Gall in 1855.

Meanwhile, the projection sacrifices accuracy of shape in favour of accuracy of scale. While the bits near the equator are stretched, so, polar regions are squished.

This fixes the Greenland-Africa size matter, allowing those who apply it to obtain a sense of the comparative size of different landmasses, all while preserving straight lines of longitude and latitude.

Nevertheless, the map severely distorts the shapes of Earth's landmasses, making them all look slightly off.

Meanwhile, the straight lines on the Peters map do not represent true constant compass bearings and so are useless for navigation.

In short, what different world maps get right is the central thread here, and readers can expect follow-up reporting as the picture becomes clearer.