On a Mercator map, why does Greenland look as big as Africa?

The short answer: a map that gave up area to keep direction

The Mercator projection distorts area in exchange for keeping direction accurate. That is why Greenland looks about the same size as Africa on a world map, though UN News reports that Africa is in fact about 14 times larger. Korea's National Geographic Information Institute (NGII) defines map projection as the process of transferring the round Earth onto a flat surface such as paper. Distortion remains, by that account, at the point where the globe is flattened.

The U.S. Geological Survey (USGS) states that every flat map misrepresents the surface of the Earth in some way. So rather than asking whether a map is wrong, it may be better to ask what it preserves and what it gives up. Mercator preserves direction and gives up area.

Every flat map distorts something — the USGS map projection FAQ

The USGS map projection FAQ page makes the point that distortion cannot be avoided: no flat map can match a globe when it comes to representing the entire surface of the Earth truthfully. The Mercator description on the same page reads, in substance: "The basic Mercator projection is the only map on which a straight line drawn anywhere within its boundaries shows true direction, but distances and areas on Mercator projection maps are badly distorted near the map's polar regions." That rendering conveys the sense rather than the exact original wording, and the original can be read directly on the FAQ page on the USGS website.

NGII likewise notes that no map can reflect distance, direction, shape and area all accurately at once. NOAA's Office of Coast Survey describes the flattening of a nautical chart as the mathematical projection of positions on a sphere onto a cylindrical surface. UN News reports that area was the price paid for preserving direction, and the same report notes that landmasses appear progressively larger the farther they lie from the equator. Set the two explanations side by side and the distortion looks less like a mistake than like the result of a choice.

A projection published in 1569 and the realities of chart work — NOAA's nautical cartography guide

UN News reports that the Flemish cartographer Gerardus Mercator devised the projection in 1569 to solve a practical problem of sea navigation. NOAA's Office of Coast Survey likewise gives 1569 as the first publication of the rectangular Mercator projection. NGII explains that the projection was built for long-distance voyages, because a ship can sail between two points on a single constant bearing.

NOAA explains why most nautical charts use the Mercator projection in terms of straight lines: a straight line drawn on the chart is a line of constant course, a rhumb line. ECDIS and many other navigation systems that use electronic navigational chart (ENC) data display in Mercator too. The agency's chart scales run from 1:2,500 to 1:10 million, and publication of traditional paper charts ended in 2024.

NGII notes that there is no distortion of area around the equator, where the cylinder touches the globe, and that the distortion grows more severe toward the poles. So if you use a projection built for the sea to compare areas, the mismatch can be expected to grow large.

The 2026 UN General Assembly resolution A/80/L.104 and the Equal Earth projection

The UN Office of the Special Adviser on Africa (OSAA) states that the General Assembly adopted resolution A/80/L.104, "Correct the Map", on 4 September 2026, in a push led by Togo and the African Union. UN News reports a vote of 164 to 1: the United States cast the only vote against, calling the initiative part of a "radical ideological project". Six countries abstained — Estonia, Georgia, Lithuania, Moldova, Serbia and Ukraine. Hours before the vote, French Foreign Minister Jean-Noël Barrot announced plans to abandon the Mercator projection on world maps.

OSAA explains that the resolution neither bans the Mercator projection nor mandates a replacement. Instead it encourages the use of equal-area maps such as the Equal Earth projection when relative size matters, and it recommends teaching the limits of flat maps in representing a spherical planet. Equal-area maps, OSAA notes, do not enlarge Africa; they strip away the exaggeration Mercator gives to land near the poles.

The resolution points to the Equal Earth projection, developed in 2018, as a projection that represents relative size more accurately. "The Equal Earth map projection", a 2019 paper published by Monash University, introduces it as an equal-area pseudocylindrical projection for world maps. It took its inspiration from the widely used Robinson projection but differs in preserving the relative areas of regions, and its projection equations are simple to implement and fast to compute. NGII, for its part, describes the Peters projection as accurate in area though unlike reality in shape.

Which projections institutions and publications actually use

Line the same question up institution by institution and the choices diverge. The USGS used only the polyconic projection for decades; today its published maps use several common projections. For large-scale maps such as topographic quadrangles and the State Base Map series, it uses conformal projections such as the transverse Mercator and the Lambert conformal conic. Its 1:24,000 7.5-minute topographic maps, based on the transverse Mercator, are nearly accurate in every respect, the agency explains. High-latitude distortion is extreme on small-scale world Mercator maps, yet on a transverse Mercator map that correctly positions a narrow area at the same high latitude, that distortion all but disappears.

Item by item, it looks like this. NOAA's Office of Coast Survey uses the Mercator projection for nautical charts, at scales from 1:2,500 to 1:10 million. The USGS published John P. Snyder's "Map projections: A working manual" as Professional Paper 1395 in 1987, with a main text of 385 pages, and Crossref counts 674 publications citing the report. The same agency designed the Space Oblique Mercator to map the Earth continuously from satellites with low distortion. NGII makes Korea's domestic maps with the transverse Mercator projection, which turns the cylinder 90 degrees to minimise distortion, and has produced its world maps with the Robinson projection since 2011. Readers curious about area figures can also read our separate article on Korea's land area.

A paper in the Journal of the Korean Cartographic Association set out to determine the most suitable projection for maps of the area around South Korea. It weighed four candidates: the Lambert conformal conic, the Albers equal-area conic, the Lambert azimuthal equal-area and the azimuthal equidistant projections. For the distortion analysis, a local distortion index at infinitesimal scale was judged the most appropriate measure, and PDAT (Projection Distortion Analysis Tool), built on that index, served as the analysis platform. After the overall review, the final projection was the Lambert azimuthal equal-area. The paper can be found on the article information page of the National Research Foundation of Korea's KCI portal.

Wrapping up

The answer lies in what the projection was for. Mercator keeps direction and gives up area, all for the sake of navigation. That is why Greenland looks much like Africa on a map, while UN News reports that Africa is about 14 times larger. No map, NGII notes, can be accurate in distance, direction, shape and area all at once.

OSAA sums it up: no projection can reproduce the Earth's curved surface perfectly on a plane. Each one sacrifices some of area, shape, distance and direction, and each suits different uses. The USGS states that shape is somewhat distorted on all equal-area maps. The 2026 resolution is not binding and the Mercator projection is not going away, so the standard for choosing a map can be said to come down to what you are trying to compare.