The Gall-Peters Projection is a rectangular map the provides users with a flat view of the entire world on a single image. It requires that all sizes have the same correct dimensions relative to each other, making it an equal-area projection. That means it must distort most of the displayed shapes to achieve this goal. The latitudes that are 45 degrees north and south are regions that don’t have this issue.
This project is named after Arno Peters and James Gall. Peters made the map available to a broader audience in the 1980s by creating the “Peters World Map” for distribution. Gall first described this idea at a science convention in the mid-19th century and then published a paper on it in 1885.
UNESCO promotes the use of the Gall-Peters projection, and this option is widely used in British schools. Boston became the first public school district in the United States to adopt this map as its standard in 2017.
Several advantages and disadvantages of the Peters Projection are worth noting.
List of the Advantages of the Peters Projection
1. Areas of equal size on the planet are also of similar size on the map.
The goal of the Peters projection was the same as many other maps that developed in the 1970s. Specific areas of accuracy were highly desirable for publishers as a way to connect with potential customers. The design of this option specifically looks at the areas of equal size that are on our planet from a continental view. Then it creates an image that reflects this on the map itself. Although this issue results in some severe areas of distortion, there are also many areas of excellent accuracy.
2. It started social conversations about the roles that maps play in society.
Although the political ramifications of the Peters projection are often the primary sticking point for this map, it wasn’t a design that was unanimously disparaged by the cartographic and geographic communities. One of the benefits that this work produced was the beginning of a conversation about the social implications that a single projection can provide. Since all maps are political in some way (a globe might be the only exception), the usefulness of the tool is based on the needs of the user.
3. The projection helps to keep the proportion of countries equalized.
The Peters projection is still an equal-area map. Whereas the Mercator design inflates the sizes of regions as they gain distance from the equator, this option works to keep the borders of equal size on the map even with the distortions in place. That means the less powerful countries in the world would at least have their proper proportions restored so that the idea that they are smaller than the nations to the north or south disappeared.
4. It is a simple way to highlight the borders of each continent.
Because of the equitable size features that are found on the Peters projection, it is very easy to highlight the different continents on the planet for learning purposes. This benefit is quite useful for determining the border between Europe and Asia. Although boundaries can change to cause the map to become inaccurate as time passes, if they get displayed on the map, the overall sizes and scope of the continents have much less variability.
Because the continent shapes remain consistent, it is simple for cartographers to update the world map when political changes occur. That makes it easier to provide current information to users, while the overall value of the previous projections remains for instructional purposes.
5. The Peters projection displays the world in a way that most people perceive it.
The reason why the United Nations uses the Peters projection is that it displays the continents in a manner that most people visualize them. Most countries are stretched pole-to-pole with this design, especially when they get intercepted by the equator. Although that means it has become less relevant when compared to other projections, the view it offers provides consistency for learning. If you know what the equations are to calculate the distance and distortion factors, then it is quite easy to understand the mechanics that the cartographers hoped to accomplish with this approach.
6. It shows the areas of ocean water accurately.
Even though the Peters projection doesn’t take into account every significant body of water, it does capture the essence of the ocean’s borders around the world. It displays the shape with accuracy, even when there are areas of extreme distortion at the poles. This benefit doesn’t provide navigable options for use, but it will create learning opportunities for students who are just beginning to review geographic concepts. That makes it easier to identify the specific areas of the world.
7. The Peters projection offers equal positions.
All of the east-west lines run parallel to each other in the Peters projection. That means the relationship of any point on this map to its distance from the equator can get easily calculated. It is also possible to use this geographic reference too to measure the angle of the sun because of the consistency found with the lines of latitude and longitude.
All north-south lines run vertically on the Peters projection to create a similar benefit. It creates an outcome where the geographic points are viewable in their correct relationship from any directional perspective.
8. It is a useful projection for specific tasks.
Projections that use an equal area or equivalent like the Peters version are useful for specific tasks, such as comparing the population density of countries or continents. The areas of the landmasses remain correct, even though there is some distortion present. This issue applies to most maps because an international treaty in 1884 agreed that the 0-degree line of longitude would become the Prime Meridian, passing through the Greenwich Observatory in England. Since most maps place this line at the center of the projection, it creates the perception that Europe and North America are “more important.”
List of the Disadvantages of the Peters Projection
1. The Peters projection suffers extreme distortion at the poles.
The Peters projection experiences severe distortion issues at each of the poles when displayed on the map. This issue applies to any design that uses the cylindrical projection option. The distortion along the equator is also considerable. It allows for the undistorted presentation of the middle latitudes, which some critics feel is ironic since Peters was born in Germany. Since the low latitudes typically host the technologically underdeveloped countries, there is a feeling that a conscious or unconscious bias may apply to this imagery.
2. This map lacks distance fidelity in almost every circumstance.
The Peters projection makes the claim of having distance fidelity, but it is an inaccurate statement to make except along the 45th parallel, both north, and south. Even then, that option only applies in the direction of those lines. Although no planetary projection succeeds at preserving distances everywhere, the cylindric approach taken with this option is especially unfortunate because the east-west ranges have no other choice but to balloon outward toward the poles.
3. Peters didn’t finish the cartography work on the map.
Peters helped to design the initial cartography for his projection. Whether he based it on Gall’s initial work in the 19th century is up for debate. What we do know about his work is that he decided to delegate the responsibilities of completing the map to someone else because he became overwhelmed with the technical components of the job. Terry Hardaker, representing Oxford Cartographers Ltd., took over the responsibility of being the official cartographer of the projection because of this disadvantage.
4. Antarctica is dramatically distorted on the Peters projection.
The Peters projection encounters the same problem with Antarctica as most other cylindrically inspired maps that give users a flat view of the planet. The continent on the bottom of the world stretches across almost the entire map. This issue provides an unrealistic view of the scale of the landmass, and it may even include glacial structures in the sea that might not be present throughout the year.
5. Greenland and northern Canada have severe distortions.
When users look toward the northern pole of the planet, distortions are evident there that provide an unrealistic view of the land. Greenland receives the majority of this issue, with the areas above the Arctic Circle receiving compression to create a flattening effect. Parts of Europe, Canada, and Alaska receive this treatment as well, with the islands to the north particularly distorted to the point where the definition of the landmasses is almost impossible to render.
6. It is almost impossible to view the island nations of the Pacific and Indian Oceans.
The Peters projection uses large squares and rectangles to indicate the presence of the various island chains that are found in the oceans around the world. Although some regions receive high levels of accuracy, such as the Caribbean, the small nations in the Pacific and Indian Oceans are barely notable on this map. The only reason why you would know that they are there is due to the borders placed above the lines of latitude and longitude. That means there are still issues with size in relation to the continents and more powerful countries for those living in these areas.
7. This projection was part of the 1989 ban on rectangular coordinate maps.
The Peters projection was part of the 1989 resolution that brought several groups together to call for a ban on all rectangular coordinate maps. Although it didn’t include all of the professional geographic organizations in North America, it did involve the American Cartographic Association, the National Geographic Society, the Association of American Geographers, and the National Council for Geographic Education.
8. It cuts off a portion of Asia to place it on the other side of the world.
One of the classic problems with modern cartography from a two-dimensional standpoint is how to handle the placement of the Kamchatka Peninsula. This region of Russia has more than 100,000 square miles of space and is 780 miles in length as it stretches into the Bering Strait. Cape Prince of Wales, which is the westernmost point on the mainland of the Americas, is only 51 miles from Cape Dezhnev on the Russian mainland. This closeness has even led to discussions about the construction of a rail tunnel under the water that’s 64 miles long to connect the two continents.
This proximity issue often causes the Russian peninsula to appear on the western side of a projection even though it is considered part of the east. The Peters projection is no exception to this rule, and the purpose is to include the Aleutian Islands along the west as they run underneath the peninsula.
Note: Some updated versions of the Peters World Map do not contain this disadvantage, but it comes at the expense of additional distortion of Alaska and the Kamchatka Peninsula.
Although maps like the Peters projection provide useful reference information, the use of rectangular coordinate processes has fallen out of favor for the Robinson projection. Since 1998, many geographic associations have been using the Winkel Tripel projection instead because of its balance between shape and size. It’s considered a superior option because it presents the world as being globe-like instead of two-dimensional, an unrealistic representation.
The United Nations might prefer the Gall-Peters projection because of its improvements to equality in size, but this issue doesn’t address the distortion at the equator and the poles. Schools use maps like this for instructional purposes, but this approach must come with the knowledge that it isn’t a 100% accurate representation.
The advantages and disadvantages of the Peters projection are essential to review when looking at the development of maps over the years. This effort may have been more than a century in the making from its original conception, but it has also served its purpose to start the political conversations that are necessary when reviewing information in social or instructional environments.
Brandon Miller has a B.A. from the University of Texas at Austin. He is a seasoned writer who has written over one hundred articles, which have been read by over 500,000 people. If you have any comments or concerns about this blog post, then please contact the Green Garage team here.