a picture of earth from space

a picture of earth from space

Cartographers, or mapmakers, must convert a 3-D sphere into a 2-D map to depict the Earth. And that’s a lot more difficult than it seems. Squeezing the globe into a flat picture typically distorts many surface characteristics. Some people enlarge. Others contract, sometimes significantly. Three scientists have devised an intelligent method to reduce these distortions. 

Their main gimmick? Separate the map into two pages. 

Mapping the Earth

“Wow!” said Elizabeth Thomas upon discovering the new map of Earth. Thomas is a climate scientist at the New York University of Buffalo. She believes that maps created in the new method might be pretty valuable. For example, it better conveys to scientists like her who research the Arctic how remote this region is from the rest of the world. It also demonstrates how significant the Arctic truly is. 

“With this new form of projection, anything that requires displaying data on maps will be easier,” she adds. “This includes variations in ocean currents, for example. It might also aid in determining the average position of meteorological fronts such as the polar vortex.” 

A projection is a sketch of a curving object (such as the Earth’s surface) onto a flat sheet of paper. Many different types of maps have been created over the ages by mapmakers. All of these factors alter the relative size of Earth’s features. 

The Mercator projection is the most often used Earth projection these days. It may even be on the wall of your classroom. It is nice, yet it has flaws. Parts farthest from the equator appear considerably more prominent than they are. Greenland, for example, appears more prominent than Africa while being just 7% the size. Despite being just one-fourth the size of Australia, Alaska appears to be roughly the same size. 

Projection Scaling

Some projections alter the distances between locations on Earth as well. This implies that the map comes to a halt at the edge of the paper and then resumes at the far edge of the page. It is known as a boundary problem because it provides the illusion of significant gaps between locations that are closer together. Hawaii, for example, is significantly closer to Asia than it appears using a Mercator projection. 

No single projection is always the best. Google uses a variant of it for city maps. Other estimates may do better in terms of distance or continent size. For its global maps, the National Geographic Society uses the Winkel tripel projection. However, no map fully depicts the entire globe. 

Nonetheless, many individuals would like a map with as few distortions as possible. That appears to be what three scientists are currently offering. On February 15, they published a paper on ArXiv explaining their novel mapmaking approach. It’s an academic article database that’s available online. 

Checking for Accuracy

Astrophysicists J. Richard Gott and David Goldberg Gott is a professor at Princeton University in New Jersey. Drexel University in Philadelphia, Pennsylvania, is where Goldberg researches galaxies. Gott was one of Goldberg’s graduate school professors. They created a technique for assessing map accuracy about a decade ago. They assigned points based on six different forms of distortion. A flawless map would have a score of zero. The Winkel tripel projection received the highest score. It had a 4.497 error score. 

Gott called Goldberg a few years ago with an idea: why does a global map have to be on one page? Why not divide the world in half and project each half on a different page? Princeton mathematician Robert Vanderbei joined the pair on this. They collaborated to develop a completely different map. It has a low error score of 0.881. “When compared to the Winkel tripel, our map outperforms it in every category,” Goldberg adds.