Lambert Azimuthal Equal Area

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An azimuthal, equal area, nonperspective projection.

 

Scale

 

True only at the center in all directions. Decreases with distance from the center along radii. Increases with distance from the center in a direction perpendicular to radii.

 

Distortion

 

Only the center is free from distortion. Distortion is moderate for one hemisphere but becomes extreme for a map of the entire Earth.

 

Usage

 

Frequently used in the polar aspect in atlases for maps of polar regions and of Northern and Southern Hemispheres. The Equatorial aspect is commonly used for atlas maps of the Eastern and Western Hemispheres. The oblique aspect is used for atlas maps of continents and oceans. The Equatorial and oblique aspects are used by the U.S. Geological Survey in cooperation with others for maps of the Circum-Pacific Map Project.

 

Recommended for equal area maps of regions approximately circular in extent.

 

Limitations

 

Use only for a single hemisphere.

 

Origin

 

Presented by Johann Heinrich Lambert (1728-1777) of Alsace in 1772. Also known as Lorgna (for the polar aspect), Zenithal Equal-Area or Zenithal Equivalent.

 

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Johann Heinrich Lambert

 

Lambert served at the Berlin Academy of Sciences, a contemporary of Euler and Lagrange. An extraordinary mathematician, he is best known as the first to prove rigorously that pi is irrational.

 

Options

 

Specify the first standard parallel and longitude origin to center the map projection to the area to be mapped. Specifying a non-Equatorial or non-polar origin causes an oblique projection.