Goodes Homolosine

Description

Goode's homolosine map projection is designed to minimize distortion for the entire world. It is an interrupted pseudocylindrical equal-area projection. John Paul Goode developed the projection in 1925.

An illustration of the land-oriented version of Goode's homolosine projection.
The land-oriented version of Goode's homolosine projection
An illustration of the ocean-oriented version of Goode's homolosine projection.
The ocean-oriented version of Goode's homolosine projection

Projection method

Goode's homolosine projection is a combination of the Mollweide and sinusoidal projections. The Mollweide projection is used for north of 40° 44' and south of -40° 44', approximately. The sinusoidal projection is used between those two latitude values for the equatorial part of the world. Both projections are equal area and pseudocylindrical. The projections are interrupted so that either the land masses (except for Antarctica) or the oceans are connected.

Linear graticules

All latitudes are straight lines. There are six straight longitude lines due to the interrupted nature of the projection. Each lobe has its own central meridian, although the overall central meridian is zero. You can change the overall central meridian, but that will cause the land masses or oceans to no longer be contiguous. For the land-oriented version, the straight longitude values are -100 and 30 in the northern hemisphere and -160, -60, 20, and 140 in the southern hemisphere. The ocean-oriented version uses -140, -10, and 130 in the northern hemisphere and -100, 20, and 140 in the southern hemisphere.

Properties

Shape

There is no distortion along the central meridians of the interrupted lobes and the equator of the sinusoidal portion (between +/-40° 44').

Area

Areas are represented accurately.

Direction

Local angles are correct along the central meridians of the lobes and the equator in the sinusoidal portion but distorted elsewhere.

Distance

The scale along all parallels in the sinusoidal part (between +/-40° 44') and the central meridians of the lobes of the projection is accurate.

Limitations

Goode's homolosine is useful only for world maps.

Uses and applications

The projection is used for equal-area world maps, mainly for raster data. The United States Geological Survey (USGS) Center for Earth Resources Observation and Science (EROS) center provides data in Goode's homolosine.

Parameters

Desktop

  • False Easting
  • False Northing
  • Central Meridian
  • Option

The Option parameter is used to set the land or ocean versions. Use 1 for the uninterrupted land masses. Use 2 for the uninterrupted ocean version. You can modify the value of the central meridian also, but doing so will cause interruptions in the land masses or the oceans.

Related Topics

7/31/2013