Natural Earth

Description

The Natural Earth projection is a compromise pseudocylindrical map projection for world maps. The projection has rounded corners where lateral meridians meet the pole lines, which suggest that the Earth has a rounded shape.

It was specifically designed by Tom Patterson for displaying physical data in 2007. Bojan Šavrič, Tom Patterson, and Bernhard Jenny published the math for the projection in 2011. It is available in ArcGIS Pro 1.2 and later and in ArcGIS Desktop 10.4 and later.

An example of the Natural Earth projection
The Natural Earth projection is shown centered on Greenwich.

Projection properties

The subsections below describe the Natural Earth projection properties.

Graticule

Natural Earth is a pseudocylindric projection. The meridians are regularly distributed polynomial curves mimicking elliptical arcs. They are concave toward the central meridian and do not intersect the parallels at right angles. The parallels are unequally distributed straight lines. The equator, both poles, and central meridian are projected as straight lines. The central meridian is 0.52 times the length of the projected equator. The bounding meridians have a rounded appearance where they meet with pole lines. The graticule is symmetric across the equator and the central meridian.

Distortion

The Natural Earth projection is neither conformal nor equal-area. It generally distorts shapes, areas, distances, directions, and angles. Distortion patterns are similar to common compromise pseudocylindrical projections. Area distortion grows with latitude and does not change with longitude. High latitude areas are exaggerated. Angular distortion is moderate near the center of the map and increases toward the edges. Distortion values are symmetric across the equator and the central meridian.

Usage

The Natural Earth projection is appropriate for general world maps.

Limitations

The Natural Earth projection is supported on spheres only. For an ellipsoid, the semimajor axis is used for the radius.

Parameters

Natural Earth parameters are as follows:

  • False Easting
  • False Northing
  • Central Meridian

Sources

Šavrič, B., Jenny, B., Patterson, T., Petrovič, D. and Hurni, L. (2011). "A polynomial equation for the Natural Earth projection." Cartography and Geographic Information Science, 38 (4), p. 363-372. DOI: 10.1559/15230406384363

Jenny, B., Patterson, T. and Hurni, L. (2008). "Flex Projector-Interactive software for designing world map projections." Cartographic Perspectives, 59, p. 12-27. DOI: 10.14714/CP59.245.