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Cartographers for centuries worked on the challenges of representing Earth on a flat surface. Maps and their various projections have their own stories affected by the development of science, history, and cultural psychology. Is there a map that’s accurate? All projections have their pros and cons and therefore it is important to make the different projections available for use. Recently, technology has been great at providing us the tools to see our world from different perspectives, and the different projections have been added to a new version of Mapbox, which Educate Magis uses for the Interactive Schools Map.

By clicking on the Map Projections button, you can choose which of the eight projections you wish to use to browse the map or locate a school.

To see this neat new feature please follow this link. 

There are several resources available that talk about map projections at length. In this article, we just mention the ones that have been added to our Interactive Map. We are referring to the short explanations of the different map projections provided on the Mapbox page.

 

Thematic Projections

In the following three projections, curved map edges create a pleasant, rounded aesthetic suggesting classic world maps. These projections are good choices for data visualization on a global scale.

Equal Earth and Natural Earth are  Pseudocylindrical projections, with straight lines of latitude and curved lines of longitude. Winkel tripel is a Pseudoazimuthal projection with lines of latitude bending slightly inward.

The Equal Earth projection  accurately reflects sizes and is thus especially useful in data visualization when it’s important to make regional size comparisons.

A notable use of Equal Earth projection is in thematic maps on global temperature anomalies by NASA.

Equal Earth Projection

 

The Natural Earth projection looks much like Equal Earth but displays a more “natural” appearance by minimizing shape distortion at the cost of a small amount of size distortion.

The Winkel tripel projection appears taller and more rounded than Equal Earth and Natural Earth, and provides more accurate shapes with less accurate sizes. Winkel tripel is commonly regarded as one of the least distorted compromise projections. The National Geographic Society and many other educational institutions use Winkel tripel for global thematic mapping.

The curved latitude lines in Winkel tripel make it unsuitable for maps where comparing latitude is important.

 

Conic Projections 

Conic projections create a map with little distortion in the area around a specific point. Further away from this point, distortion increases. In the Albers projection, is shape distortion, while in Lambert Conformal Conic the size increases with greater distance.

The Albers projection is a conic, equal-area projection. Like Equal Earth, this projection provides accurate relative sizes, but shapes are increasingly distorted at further distances.

Albers Projection

The Lambert conformal conic projection is a conic, conformal projection used for aeronautical charts and many regional mapping systems. Like Mercator, this is a conformal projection, meaning that shapes and angles are accurately represented. Instead, regions further away from the center are increasingly exaggerated in size.

 

Rectangular Projections

Equirectangular and Mercator are classified in cartography as cylindrical projections. These projections have straight latitude and longitude lines. Their rectangular shape allows them to loop across their east and west edges at the 180th Meridian, useful for maps that need to cover the Pacific Ocean. 

The Equirectangular (Plate Carrée) projection is a cylindrical, compromise projection in which positions on the map directly correspond to their longitude and latitude values.

Equirectangular is useful for mapping the Pacific Ocean while minimizing the size distortion of Mercator.

This projection is the standard for global raster datasets, such as Celestia, NASA World Wind, and Natural Earth, and is useful for displaying these datasets without distortion.

Equirectangular Projection

The Web Mercator projection is a cylindrical, conformal projection and the default projection in Mapbox GL JS. Web Mercator is classified as EPSG:3857 and is a variant of the classic Mercator projection used for marine navigation. Web Mercator was the first projection introduced in web maps and remains widely used by most mapping platforms.

Mercator accurately displays shapes and angles, which makes it useful for navigation. At the world scale, it exaggerates the size of geographic shapes near the poles. For example, Greenland appears the same size as Africa, even though it’s 14 times smaller.

The Globe projection (defined as globe in the Mapbox GL JS API) is a three-dimensional representation of the earth. Globe increases the sense of depth of the map and is a correct representation of the surface of the earth as viewed from space. Using this projection limits the display of the earth to one hemisphere at a time. This can be addressed in some cases by rotating the globe with camera animation.