Quick Answer
The Mercator projection is a cylindrical map projection created by Gerardus Mercator in 1569. While perfect for navigation because it preserves angles and directions, it severely distorts the sizes of countries and continents, making areas near the poles appear much larger than they actually are. This is why Greenland appears almost as large as Africa on most world maps, despite Africa being 14 times bigger in reality.
The World's Most Influential Map
When you picture a world map in your mind, you're almost certainly thinking of the Mercator projection. This 450-year-old mapping technique has shaped how billions of people see our planet, but it comes with a hidden cost: it fundamentally distorts our perception of country and continent sizes.
The Big Misconception
Most people believe Greenland is roughly the same size as Africa because that's how it appears on Mercator maps. In reality, Africa could fit 14 Greenlands inside it with room to spare.
Created in 1569 by Flemish cartographer Gerardus Mercator (born Gheert Cremer), this projection was revolutionary for its time. Mercator designed it specifically for navigation, and in that purpose, it excels. However, its widespread adoption for general education and reference has created systematic misconceptions about our world's geography.
How the Mercator Projection Works
Imagine wrapping a cylinder around a globe, touching it at the equator. Now imagine a light source at the center of the globe projecting the Earth's surface onto this cylinder. When you unwrap the cylinder, you get a rectangular map - that's essentially how the Mercator projection works.
Mathematical Magic
The Mercator projection uses a mathematical formula that progressively stretches the map as you move away from the equator. This stretching happens in both directions - east-west and north-south - but it increases exponentially with latitude.
Distortion Factor by Latitude:
- • 0° (Equator): 1x (no distortion)
- • 30°: 1.15x larger
- • 45°: 1.41x larger
- • 60°: 2x larger
- • 75°: 4x larger
- • 85°: 11x larger
Why the Stretching?
As you move toward the poles on a globe, the meridians (longitude lines) converge and get closer together. But on a rectangular map, they must remain parallel and equally spaced. To maintain correct angles and shapes, the projection must stretch everything to compensate.
Real-world Impact:
This is why Antarctica appears as a massive continent stretching across the entire bottom of Mercator maps, when it's actually smaller than South America.
The History Behind the Map
The Creator
Gerardus Mercator (1512-1594) was a Flemish cartographer, geographer, and cosmographer. Born Gheert Cremer, he latinized his name to Mercator, meaning "merchant" - fitting for someone who would revolutionize trade navigation.
The Purpose
Mercator created his projection to solve a critical navigation problem: how to plot straight-line courses on a map. His projection made it possible to draw a straight line between any two points and follow that bearing with a compass.
The Impact
The projection became the standard for maritime navigation and remained so for centuries. It enabled the age of exploration and global trade by making ocean navigation significantly more reliable and accurate.
Historical Context
When Mercator created his projection in 1569, accuracy in navigation was literally a matter of life and death. Ships that couldn't find their way would run out of supplies, crash into reefs, or become lost at sea. The projection's ability to preserve directions made it invaluable for maritime exploration and trade, despite its size distortions.
Advantages and Disadvantages
✅Advantages
- •Perfect for Navigation:
Straight lines represent constant compass bearings (rhumb lines), making route planning simple.
- •Preserves Angles:
Local shapes and angles are accurate, which is crucial for detailed navigation and surveying.
- •Mathematically Simple:
Easy to construct and use calculations, which made it practical for centuries of navigators.
- •Web-Friendly:
Web Mercator is computationally efficient for online maps and zoom functions.
❌Disadvantages
- •Extreme Size Distortion:
Areas near poles appear many times larger than they actually are.
- •Cannot Show Poles:
The mathematical distortion becomes infinite at exactly 90°N and 90°S.
- •Eurocentric Bias:
Makes northern countries appear larger and more dominant than southern ones.
- •Educational Misconceptions:
Creates false impressions about relative sizes of countries and continents.
Mind-Blowing Size Comparisons
Here are some shocking size comparisons that reveal just how much the Mercator projection distorts our world:
Africa vs. Greenland
On Mercator maps:
Greenland appears roughly the same size as Africa, sometimes even larger.
In reality:
Africa is 14 times larger than Greenland (30.3 million km² vs 2.2 million km²).
Russia vs. Africa
On Mercator maps:
Russia appears larger than Africa, dominating the northern part of the map.
In reality:
Africa is 77% larger than Russia (30.3 million km² vs 17.1 million km²).
Alaska vs. Brazil
On Mercator maps:
Alaska appears larger than Brazil, taking up significant visual space.
In reality:
Brazil is 5 times larger than Alaska (8.5 million km² vs 1.7 million km²).
Scandinavia vs. India
On Mercator maps:
Scandinavia (Norway, Sweden, Finland) appears larger than India.
In reality:
India is actually larger than all of Scandinavia combined.
Why We Still Use Mercator Today
Despite its distortions, the Mercator projection remains incredibly popular. Here's why it's still the go-to choice for many applications:
🧭Navigation & GPS
Every GPS system, from your phone to ship navigation, uses Mercator-based projections because straight lines represent constant compass bearings. This makes route planning and following directions intuitive.
💻Web Maps
Google Maps, OpenStreetMap, and other web mapping services use Web Mercator because it's computationally efficient for tile-based mapping systems and seamless zooming.
🏫Educational Familiarity
Most people grew up with Mercator world maps in classrooms. This familiarity makes it the default choice, despite better alternatives existing for size comparison.
📏Local Accuracy
For small areas and city maps, Mercator's distortions are minimal while its angle preservation makes it perfect for detailed navigation and urban planning.
Better Alternatives for Size Comparison
While Mercator is perfect for navigation, other projections are much better for understanding true country sizes and global relationships:
Gall-Peters Projection
Preserves area relationships perfectly, showing countries in their true relative sizes. Adopted by UNESCO for educational materials because it gives a more accurate view of world proportions.
Best for: Understanding true country sizes, global education, addressing colonial-era biases
Winkel Tripel Projection
National Geographic's current standard, this projection minimizes all types of distortion by finding the best compromise between area, distance, and direction accuracy.
Best for: General reference maps, atlases, balanced world representation
AuthaGraph Projection
A modern projection that preserves area relationships while maintaining recognizable shapes. Winner of the Good Design Award and increasingly popular in Japanese education.
Best for: Modern education, accurate size representation with familiar shapes
Frequently Asked Questions
What is the Mercator projection?
The Mercator projection is a cylindrical map projection developed by Flemish cartographer Gerardus Mercator in 1569. It preserves angles and shapes locally, making it ideal for navigation, but severely distorts the sizes of landmasses, especially those far from the equator.
Why does Greenland look so big on Mercator maps?
Greenland appears disproportionately large on Mercator maps because it's located far from the equator (around 60-83°N latitude). The Mercator projection stretches areas increasingly as they get farther from the equator, making Greenland appear about the same size as Africa when Africa is actually 14 times larger.
What are the advantages of the Mercator projection?
The Mercator projection's main advantages are: 1) It preserves angles and directions perfectly, making it ideal for navigation, 2) Straight lines on the map represent constant compass bearings, 3) Local shapes are preserved accurately, and 4) It's mathematically simple to construct and use for plotting courses.
What are the disadvantages of the Mercator projection?
The main disadvantages include: 1) Extreme size distortion near the poles, 2) Cannot show the polar regions, 3) Creates a Eurocentric worldview by enlarging northern countries, 4) Distorts our perception of relative country and continent sizes, and 5) Makes equatorial regions appear smaller and less important than they actually are.
How much does the Mercator projection distort sizes?
Distortion increases dramatically with latitude. At 60°N (like southern Greenland), areas appear 2x their actual size. At 75°N, they appear 4x larger. Greenland (mostly above 60°N) appears about 14x larger relative to equatorial Africa than it actually is.
Why is the Mercator projection still used today?
The Mercator projection remains popular because: 1) It's perfect for navigation and GPS systems, 2) Web mapping services use Web Mercator for its computational efficiency, 3) It's familiar to most people, 4) It works well for local areas and street maps, and 5) The navigation benefits outweigh size distortion for many practical uses.
What's the difference between Mercator and other projections?
Unlike equal-area projections (like Gall-Peters), Mercator prioritizes shape and angle preservation over size accuracy. Unlike compromise projections (like Robinson or Winkel Tripel), Mercator doesn't try to balance different distortions - it completely sacrifices size accuracy for perfect local geometry.
Can the Mercator projection show the entire world?
No, the Mercator projection cannot show the polar regions. As you approach the poles (90°N or 90°S), the distortion becomes infinite. Most Mercator world maps cut off around 85°N and 85°S, excluding parts of Antarctica and the Arctic Ocean.
Who invented the Mercator projection and when?
The Mercator projection was invented by Gerardus Mercator (born Gheert Cremer) in 1569. He was a Flemish cartographer who created it specifically for navigation purposes. His world map was titled 'Nova et Aucta Orbis Terrae Descriptio ad Usum Navigantium Emendate Accommodata' (New and more complete representation of the terrestrial globe properly adapted for use in navigation).
People Also Ask
Is the Mercator projection accurate?
The Mercator projection is perfectly accurate for angles and local shapes, making it ideal for navigation. However, it's highly inaccurate for areas and distances, especially far from the equator.
What countries look biggest on Mercator maps?
Countries furthest from the equator appear largest: Greenland, Canada, Russia, Alaska, and Scandinavia all appear dramatically oversized compared to equatorial countries like those in Africa or South America.
Why don't schools use better map projections?
Many schools are transitioning to better projections, but Mercator remains common due to familiarity, cost of replacing materials, and its usefulness for teaching navigation concepts.
How does Mercator affect our worldview?
The Mercator projection can create unconscious biases by making northern, often wealthier countries appear larger and more important than southern, often developing countries.
What's Web Mercator?
Web Mercator is a modified version used by Google Maps and other online services. It's optimized for digital maps and seamless zooming, making it perfect for web applications.
Are there any countries that look smaller on Mercator?
Countries near the equator appear relatively smaller on Mercator maps. This includes most of Africa, South America, Southeast Asia, and equatorial regions that get compressed compared to polar areas.
Experience the Distortion Yourself
See how dramatically country sizes change when you move them around the map. Drag Greenland to the equator and watch it shrink to its true size!