Eckert VI

Description

This equal-area projection is used primarily for world maps.

Illustration of Eckert VI projection

Projection method

A pseudo cylindrical equal-area projection.

Linear graticules

Parallels are unequally spaced straight lines. They are closer together at the poles. Meridians are equally spaced sinusoidal curves. The poles and the central meridian are straight lines half as long as the equator.

Properties

Shape

Shapes are stretched north–south 29 percent along the equator, relative to the east–west dimension. This stretching decreases to zero at 49°16' N and S at the central meridian. Nearer the poles, features are compressed in the north–south direction.

Area

Equivalent.

Direction

Local angles are correct at the intersection of 49°16' N and S with the central meridian. Direction is distorted elsewhere.

Distance

Scale is distorted north–south 29 percent along the equator relative to the east–west dimension. This distortion decreases to zero at 49°16' N and S at the central meridian. Scale is correct only along these parallels. Nearer the poles, features are compressed in the north–south direction.

Limitations

Useful only as a world map.

Uses and applications

Suitable for thematic mapping of the world.

Used for world distribution maps in the 1937 World Atlas by the Soviet Union.

Parameters

Desktop

  • False Easting
  • False Northing
  • Central Meridian
NoteNote:

Supported on spheres only.

Eckert VI Auxiliary Sphere (Desktop version 9.3 and later)

  • False Easting
  • False Northing
  • Central Meridian
  • Auxiliary Sphere Type
NoteNote:

The Auxiliary Sphere Type parameter accepts 0 (use semimajor axis or radius of the geographic coordinate system), 1 (use semiminor axis or radius), 2 (calculate and use authalic radius), or 3 (use authalic radius and convert geodetic latitudes to authalic latitudes).

Workstation

  • Longitude of Central Meridian
NoteNote:

Supported on spheres only.

Related Topics


7/31/2013