Equal Earth projection

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Equal Earth projection. 15deg graticule. Imagery is a derivative of NASA's Blue Marble summer month composite with oceans lightened to enhance legibility and contrast. Image created with the Geocart map projection software. Equal Earth projection SW.jpg
Equal Earth projection. 15° graticule. Imagery is a derivative of NASA’s Blue Marble summer month composite with oceans lightened to enhance legibility and contrast. Image created with the Geocart map projection software.

The Equal Earth map projection is an equal-area pseudocylindrical projection for world maps, 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, retains the relative size of areas. The projection equations are simple to implement and fast to evaluate. [1]


The features of the Equal Earth projection include: [2] [3]

According to the creators, 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, which generated a controversy in the world of cartography. At that time Šavrič, Patterson and Jenny 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. [3] [4] [5] [6] They claim that they need a world map that shows continents and countries in real size with each other. [2]


Equal Earth projection distortion. Deeper color means more distortion. Tissot indicatrix at 15deg intervals. Equal Earth projection distortion.jpg
Equal Earth projection distortion. Deeper color means more distortion. Tissot indicatrix at 15° intervals.

The projection is formulated as the equations


and refers to latitude and to longitude.


The Equal Earth compared to similar equal-area pseudocylindrical projections. The-Equal-Earth-compared-to-similar-equal-area-pseudocylindrical-projections.png
The Equal Earth compared to similar equal-area pseudocylindrical projections.

The first known thematic map published using the Equal Earth projection is a map of the global mean temperature anomaly for July 2018, produced by the NASA’s Goddard Institute for Space Studies. [7]

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  1. Šavrič, Bojan; Patterson, Tom; Jenny, Bernhard (2018-08-07). "The Equal Earth map projection". International Journal of Geographical Information Science . 33 (3): 454–465. doi:10.1080/13658816.2018.1504949.
  2. 1 2 "Equal Earth projection". shadedrelief.com. Retrieved 2018-08-23.
  3. 1 2 Morales, Aurelio. "La nueva proyección Equal Earth: todo lo que debes saber" (in Spanish). Valladolid: MappingGIS. Retrieved January 24, 2020.
  4. "Equal Earth: un mapamundi más preciso que muestra el tamaño real de África" (in Spanish). N+1. August 22, 2018. Retrieved January 24, 2020.
  5. "Equal Earth: Idean un nuevo mapa del mundo basado en un mapa del 1569" (in Spanish). Código Oculto. Retrieved January 24, 2020.
  6. "Colección cartográfica - La proyección Equal-Earth". visionscarto (in Spanish). Retrieved January 24, 2020.
  7. "NASA GISS on Twitter". Twitter. Retrieved 2018-08-23.