Understanding Map Projections
The Fundamental Problem
It's impossible to display the curved surface of Earth on a flat map without some form of distortion. Every map projection makes compromises, and understanding these trade-offs is crucial for interpreting geographic information accurately.
Common Map Projections
Mercator Projection
Purpose:
Designed for marine navigation in 1569 by Gerardus Mercator
Preserves:
Angles and shapes (conformal projection)
Distorts:
Areas, especially near the poles. Greenland appears as large as Africa!
Best for:
Navigation, web maps (Google Maps, OpenStreetMap)
Equal Earth Projection
Purpose:
Created in 2018 for accurate area representation
Preserves:
Areas (equal-area projection)
Distorts:
Shapes slightly, but minimally compared to other equal-area projections
Best for:
Comparing country sizes, thematic mapping, education
Types of Distortion
Map projections can distort four main properties of geographic features:
Area Distortion
Changes in the relative size of geographic features. Mercator dramatically exaggerates areas near the poles.
Shape Distortion
Changes in the angles and shapes of features. Equal-area projections sacrifice shape accuracy to preserve area.
Distance Distortion
Changes in the scale and relative distances between points. No projection can preserve all distances accurately.
Direction Distortion
Changes in bearing and direction between points. Mercator preserves direction for navigation purposes.
Real-World Examples of Distortion
Surprising Size Comparisons
- • Greenland vs. Africa: Greenland appears similar in size to Africa on Mercator maps, but Africa is actually 14 times larger!
- • Alaska vs. Brazil: Alaska looks huge on most maps, but Brazil is actually 5 times larger.
- • Scandinavia vs. India: The Nordic countries appear larger than India, but India is actually 3 times bigger.
- • Russia vs. Africa: While Russia is indeed massive, Africa is still 1.7 times larger in area.
Why This Matters
Our perception of the world is heavily influenced by the maps we see. When we consistently view distorted representations, it affects our understanding of:
- Global politics: Countries that appear larger may seem more important or powerful
- Climate change: Understanding the true scale of polar ice sheets and their melting
- Population density: Comparing how people are distributed across different regions
- Economic development: Relating country sizes to their economic output and resources
- Cultural awareness: Appreciating the true scale and diversity of different regions
Interactive Learning
Our ResizeEarth tool helps you understand these concepts through direct interaction. By switching between Web Mercator and Equal Earth projections, you can see firsthand how different projections affect your perception of country sizes.