Sinusoidal

Description

Also known as Sanson–Flamsteed—as a world map, this projection maintains equal area despite conformal distortion. Alternative formats reduce the distortion along outer meridians by interrupting the continuity of the projection over the oceans and by centering the continents around their own central meridians, or vice versa.

Projection method

A pseudo cylindrical projection where all parallels and the central meridian are straight. The meridians are curves based on sine functions with the amplitudes increasing with the distance from the central meridian.

Linear graticules

All lines of latitude and the central meridian.

Properties

Shape

No distortion along the central meridian and the equator. Smaller regions using the interrupted form exhibit less distortion than the uninterrupted sinusoidal projection of the world.

Area

Areas are represented accurately.

Direction

Local angles are correct along the central meridian and the equator but distorted elsewhere.

Distance

The scale along all parallels and the central meridian of the projection is accurate.

Limitations

Distortion is reduced when used for a single land mass rather than the entire globe. This is especially true for regions near the equator.

Uses and applications

Used for world maps illustrating area characteristics, especially if interrupted.

Used for continental maps of South America, Africa, and occasionally other land masses, where each has its own central meridian.

Parameters

Desktop

• False Easting
• False Northing
• Central Meridian

Workstation

• Radius of the sphere of reference
• Longitude of Central Meridian
• False Easting (meters)
• False Northing (meters)

Note:

Supported on spheres only.