Equal Earth projection

Equal-area pseudocylindrical global map projection

The Equal Earth map projection is an equal-area pseudocylindrical global map projection invented by Bojan Šavrič, Bernhard Jenny, and Tom Patterson in 2018. It is inspired by the widely used Robinson projection, but unlike the Robinson projection, it retains the relative size of areas, and the projection equations are designed to be simple to implement and fast to evaluate.^[1]

The creators of the Equal Earth projection intended it to be used only when an equal-area projection was strictly mandated. When publishing its specifications, they warned that equal-area projections are not the panacea that these organizations might think. For example, continental shapes suffer.^[1]

Following a public campaign called "Correct the Map" to promote the Equal Earth projection, and a resolution by the African Union to officially adopt the projection, the United Nations General Assembly approved a resolution addressing the projection in September 2026. The resolution discouraged use of the Mercator projection for most uses other than navigation, while encouraging the use of equal-area projections instead, and favorably mentioning Equal Earth as an option.^[2] The resolution was expected to affect educational and technological applications.^[3]

The projection was created in response to the decision of the Boston Public Schools to adopt the Gall–Peters projection for world maps in March 2017 to accurately show the relative sizes of equatorial and non-equatorial regions. The decision generated controversy in the world of cartography due to that projection's extreme distortion in the polar regions. At that time, Šavrič, Jenny, and Patterson sought alternative map projections of equal areas for world maps, but could not find any that met their aesthetic criteria. Therefore, they created a new projection that had more visual appeal compared to existing projections of equal areas.^[4][5][6][7]

One result of using any equal-area projection is to improve representation of developing countries near the equator, particularly in Africa, compared to the distorted relative sizes of the countries on non–equal-area projections. For example, on the Mercator projection, Greenland appears to be larger than the whole of Africa, when in reality it only has 7% of the total land area of Africa. These incorrect proportions can lead to misrepresentation of the effects of communicable diseases.^[8] Equal-area projections do not cause that problem, but they do distort the shape of the continents. As an equal-area projection, the Equal Earth projection precisely represents the true area of each country.^[8]

As with the earlier Natural Earth projection (2012) introduced by Patterson, a visual method was used to choose the parameters of the projection. A combination of Putniņš P4ʹ and Eckert IV projections was used as the basis. Mathematical formulas for the projection were derived from a polynomial used to define the spacing of parallels. The projection is formulated as the equations:

$${\displaystyle {\begin{aligned}x&={\frac {2{\sqrt {3}}\,\lambda \cos {\theta }}{3\,(9\,A_{4}\,\theta ^{8}+7\,A_{3}\,\theta ^{6}+3\,A_{2}\,\theta ^{2}+A_{1})}}\\y&=A_{4}\,\theta ^{9}+A_{3}\,\theta ^{7}+A_{2}\,\theta ^{3}+A_{1}\,\theta ,\end{aligned}}}$$

where

$${\displaystyle {\begin{aligned}&\sin {\theta }={\frac {\sqrt {3}}{2}}\sin {\varphi }\\&A_{1}=1.340264,\ A_{2}=-0.081106,\ A_{3}=0.000893,\ A_{4}=0.003796.\end{aligned}}}$$

and ${\displaystyle \varphi }$ refers to latitude and ${\displaystyle \lambda }$ to longitude (all angles in radians).

With these parameters, the equatorial and polar semimajor axes are:

$${\displaystyle {\begin{aligned}x(\theta (0),\pi )&=0.861547\ \pi =2.70663\\y\left(\theta \left({\frac {\pi }{2}}\right)\right)&=1.31736\end{aligned}}}$$

for a ratio of 2.05458:1, a value chosen for aesthetic reasons and very close to the “natural ratio” of a sphere (180°/90°).^[1]

Since the surface of a sphere cannot be mapped onto a plane without distortion, all (planar) maps distort shapes in one way or another. The distortion can be visualized using an index called "Tissot's Indicatrix",^[9] which shows how the size and shape of an infinitesimal circular area is projected onto the map.

In the Equal Earth projection, a small area on the surface of the Earth shows its accurate shape on the central meridian (0°) at a latitude of 40.4° North or South.^[10] At locations closer to the equator than this, shapes are elongated in the north-south direction and compressed in the east-west direction, reaching a maximum shape distortion of 1.35. At locations poleward of 40.4°, shapes are elongated E-W and compressed N-S, with an elongation ratio approaching infinity at the pole (mapping the pole itself to a horizontal line rather than a point.) East and west of the central meridian of 0°, at locations away from the equator the ellipses become tilted, with the north-south axis of the ellipse pointed toward the central meridian.

One of the first known thematic maps published using the Equal Earth projection^[11] is a map of the global mean temperature anomaly for July 2018, produced by NASA's Goddard Institute for Space Studies.^[12]

An Equal Earth Political Wall Map by Tom Patterson^{[13]: §Terms}, designed for schools and organisations^[13]: web is labelled using United States Central Intelligence Agency map data with the Central Intelligence Agency political map as the primary reference.^{[13][non-primary source needed]} Countries are mostly the same as US government maps; however, Patterson made changes in the depiction of Myanmar (and Naypyidaw), Taiwan (and Taipei), Western Sahara (Western Sahara conflict), depiction of Crimea, a border between Kenya and South Sudan, and boundaries between China, India, and Pakistan.^{[13]: §Countries and capitals [a]}

OpenStreetMap-based maps can be created using Equal Earth projections. To view maps without coordinate calculations, vector tiles can be produced in Equal Earth projection on a Equal Earth Greenwich grid (centred on Greenwich) to be addressed using a Web Mercator grid.^[14] Mapbox supports the equalearth projection.^[15] Esri tools support Equal Earth projection.^[16]

Maps with Equal Earth projection can be centred on meridians other than the Prime meridian (London), but Africa is usually shown in the centre.^{[citation needed]} Esri ArcGIS Pro 3.7 has False Easting, False Northing and Central Meridian as available parameters.^[17] As of September 2026, Mapbox only supports the central meridian fixed at the Prime meridian (Greenwich).^[15]

United Nations resolution

[edit]

On September 4, 2026, the text to the Correct the Map resolution^[23] was adopted at the 80th session^[24] of the United Nations General Assembly.^[25][26] The resolution was to encourage the world to phase out the Mercator projection in favour of the Equal Earth projection and other equal-area projections.^{[2][3]: web [27]} UN resolutions are non-enforceable and use of the projection is not mandated,^[3] and other projections are not banned.^[28]

Of the 193 member states of the United Nations, 164 voted in favour of the resolution, six abstained (Estonia, Georgia, Lithuania, Moldova, Serbia, and Ukraine), and one voted against (United States).^[25] The resolution was put forward by African Union member states and The Bahamas.^[29] Togo asked UN member states to adopt the map in April 2026. A draft resolution was created and the United Nations General Assembly held consultations in July 2026.^[29]

The resolution links more accurate maps to "cognitive justice, historical recognition and equitable representation".^{[25]: para. 5} Equal-area projections depict Africa, Latin America, South Asia and Oceania (including Australia) much larger, and the United States^[30] and Russia^[31] smaller.

The Guardian wrote the outcome was expected to result in the update of education curriculums and general technology.^[3]: web

The Agence France-Presse published a handout map^[32], cited by news agencies as a "handout graphic by Equal Earth"^{[30]: alt text}, "AFP/Handout/Equal Earth"^[33] or "the new map".^[30]: web

Positions of member states

[edit]

The United States opposed the resolution, stating that it was "superfluous"^[3] and that it promoted a "radical ideological project" of "reparations and 'cognitive justice.'"^[34] The Australian Broadcasting Corporation said the US "slammed the resolution".^{[30]: para. 7}

Ukraine abstained from the vote, taking issue with the fact that maps published by Tom Patterson on equal-earth.com using the Equal Earth projection depicted Crimea in a different color from Ukraine.^[35][36] Ukrainian representative Andriy Melnyk said that this was inconsistent with the UN's "non-recognition of the attempted illegal annexation of Crimea by the Russian Federation in 2014"^{[25]: para. 13} and "wholly unacceptable".^{[37][38][23]: web} Similarly, after the vote, Japanese diplomats contacted Patterson asking for a change to the Kuril Islands, which were depicted in the same color as Russia.^[39]

Speaking on behalf of the European Union, the representative for Ireland^{[28]: §Borderline revolt} noted that the resolution "neither addresses nor affects questions relating to sovereignty, territorial status, delimitation, or the internationally recognized borders of States", nor does it "endorse any specific website, such as equal-earth.com, including the maps contained therein".^{[40][28]: §Borderline revolt} The vote does not establish a single mandatory map for the United Nations.^[41]

The authors of the Equal Earth projection paper stated equal-area projections such as Equal Earth are not the panacea many organisations think, as continental shapes are distorted.^[1]: 9 Equal Earth was developed as an alternative to other equal-area projections for situations when an equal-area map must be used.^[1]: 9 They have been surprised by its near-universal acceptance by the United Nations.^[39]

The Winkel tripel projection has more accurate shapes than Equal Earth with less accurate sizes, and is regarded as one of the least distorted compromise projections. The National Geographic Society and many educational institutions use Winkel tripel projection for global mapping.^{[42]: §Winkel Tripel}

The Equal Earth projection is one of many equal-area pseudocylindrical^[1] map projections.

The Natural Earth projection looks much like Equal Earth, while better preserving the shapes of the continents, but is not equal-area.^[42] The Robinson projection is another alternative of this type.

Earlier attempts to give "a truer sense of area while retaining a visually intuitive layout" and replace the Mercator projection include the Goode homolosine and Gall–Peters projection.^[43]

• List of map projections

• "Equal Earth Wall Map". equal-earth.com. Archived from the original on June 13, 2026. – a wall map for schools and organizations
• Marit Jentoft-Nilsen (March 31, 2019). "Long-term Global Warming trend, 2018 update – Global temperature anomaly for 2018". NASA's Goddard Space Flight Center, NASA Goddard Institute for Space Studies.
• "OpenEqualEarthMap". openequalearthmap.com. – a basic map showing OpenStreetMap data