Cylindrical Equal Area

Description

Lambert first described this equal area projection in 1772. It has been used infrequently.

Illustration of Cylindrical Equal Area projection

Projection method

A normal perspective projection onto a cylinder tangent at the equator.

Points of intersection

The equator.

Linear graticules

In the normal, or equatorial aspect, all meridians and parallels are perpendicular straight lines. Meridians are equally spaced and 0.32 times the length of the equator. Parallels are unequally spaced and farthest apart near the equator. Poles are lines of length equal to the equator.

Properties

Shape

Shape is true along the standard parallels of the normal aspect. Distortion is severe near the poles of the normal aspect.

Area

There is no area distortion.

Direction

Local angles are correct along standard parallels or standard lines. Direction is distorted elsewhere.

Distance

Scale is true along the equator. Scale distortion is severe near the poles.

Limitations

Recommended for narrow areas extending along the central line. Severe distortion of shape and scale near the poles.

Uses and applications

Suitable for equatorial regions.

Parameters

Desktop

  • False Easting
  • False Northing
  • Central Meridian
  • Standard Parallel 1

Workstation

  • Enter projection type (1, 2, or 3):

Type 1 parameters

  • Longitude of Central Meridian
  • Latitude of standard parallel:

Type 2 parameters

  • Longitude of 1st point
  • Latitude of 1st point
  • Longitude of 2nd point
  • Latitude of 2nd point
  • Scale factor:

Type 3 parameters

  • Longitude of center of projection
  • Latitude of center of projection
  • Azimuth
  • Scale factor
NoteNote:

Type 3 is supported on spheres only

Related Topics


7/31/2013