Goode homolosine projection

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Goode homolosine projection of the world. Goode homolosine projection SW.jpg
Goode homolosine projection of the world.
Tissot indicatrix on Goode homolosine projection, 15deg graticule. Goode homolosine projection Tissot indicatrix.svg
Tissot indicatrix on Goode homolosine projection, 15° graticule.

The Goode homolosine projection (or interrupted Goode homolosine projection) is a pseudocylindrical, equal-area, composite map projection used for world maps. Normally it is presented with multiple interruptions. Its equal-area property makes it useful for presenting spatial distribution of phenomena.

Contents

Development

The projection was developed in 1923 by John Paul Goode to provide an alternative to the Mercator projection for portraying global areal relationships. Goode offered variations of the interruption scheme for emphasizing the world’s land and the world’s oceans. Some variants include extensions that repeat regions in two different lobes of the interrupted map in order to show Greenland or eastern Russia undivided. The homolosine evolved from Goode’s 1916 experiments in interrupting the Mollweide projection. [1]

Because the Mollweide is sometimes called the "homolographic projection", Goode fused the two names "homolographic" and "sinusoidal" to create the name "homolosine". [2] Common in the 1960s, the Goode homolosine projection is often called an "orange-peel map" because of its resemblance to the flattened rind of a hand-peeled orange. In its most common form, the map interrupts the North Atlantic, the South Atlantic, the South Pacific, the Indian Ocean, and the entire east/west meridian of the map.

Details

Up to latitudes 40°44′11.8″N/S, the map is projected according to the sinusoidal projection’s transformation. The higher latitudes are the top sections of a Mollweide projection, grafted to the sinusoidal midsection where the scale of the two projections matches. This grafting results in a kink in the meridians along the parallel of the graft. The projection’s equal-area property follows from the fact that its source projections are themselves both equal-area.

See also

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John Paul Goode, a geographer and cartographer, was one of the key geographers in American geography’s Incipient Period from 1900 to 1940. Goode was born in Stewartville, Minnesota on November 21, 1862. Goode received his bachelor's degree from the University of Minnesota 1889 and his doctorate in economics from the University of Pennsylvania in 1903. Later on in 1903, he was offered a position as a professor in the Geography Department at the University of Chicago.

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The Aitoff projection is a modified azimuthal map projection proposed by David A. Aitoff in 1889. Based on the equatorial form of the azimuthal equidistant projection, Aitoff first halves longitudes, then projects according to the azimuthal equidistant, and then stretches the result horizontally into a 2:1 ellipse to compensate for having halved the longitudes. Expressed simply:

Hammer projection map projection

The Hammer projection is an equal-area map projection described by Ernst Hammer in 1892. Using the same 2:1 elliptical outer shape as the Mollweide projection, Hammer intended to reduce distortion in the regions of the outer meridians, where it is extreme in the Mollweide.

Tobler hyperelliptical projection

The Tobler hyperelliptical projection is a family of equal-area pseudocylindrical projections that may be used for world maps. Waldo R. Tobler introduced the construction in 1973 as the hyperelliptical projection, now usually known as the Tobler hyperelliptical projection.

Cylindrical equal-area projection

In cartography, the cylindrical equal-area projection is a family of cylindrical, equal-area map projections.

Waterman butterfly projection world map projection in the shape of the namesake insect

The Waterman "Butterfly" World Map is a map arrangement created by Steve Waterman. Waterman first published a map in this arrangement in 1996. The arrangement is an unfolding of a globe treated as a truncated octahedron, evoking the butterfly map principle first developed by Bernard J.S. Cahill (1866–1944) in 1909. Cahill and Waterman maps can be shown in various profiles, typically linked at the north Pacific or north Atlantic oceans.

The Eckert projections are six pseudocylindrical map projections devised by Max Eckert-Greifendorff, who presented them in 1906. The latitudes are parallel lines in all six projections. The projections come in pairs; in the odd-numbered projections, the latitudes are equally spaced, while their even-numbered counterparts are equal-area.

Boggs eumorphic projection

The Boggs eumorphic projection is a pseudocylindrical, equal-area map projection used for world maps. Normally it is presented with multiple interruptions. Its equal-area property makes it useful for presenting spatial distribution of phenomena. The projection was developed in 1929 by Samuel Whittemore Boggs (1889–1954) to provide an alternative to the Mercator projection for portraying global areal relationships. Boggs was geographer for the United States Department of State from 1924 until his death. The Boggs eumorphic projection has been used occasionally in textbooks and atlases.

Interruption (map projection) subclass of map projection

In map projections, an interruption is any place where the globe has been split. All map projections are interrupted at at least one point. Typical world maps are interrupted along an entire meridian. In that typical case, the interruption forms an east/west boundary, even though the globe has no boundaries.

Equal-area (map projection) map projection that preserves area measure, generally distorting shapes in order to do that

In map projection, equal-area maps preserve area measure, generally distorting shapes in order to do that. Equal-area maps are also called equivalent or authalic.

References

  1. Snyder, John Parr (1993). Flattening the earth : two thousand years of map projections. Chicago: University of Chicago Press. pp. 167–168. ISBN   9780226767475. OCLC   26764604.
  2. Monmonier, Mark S. (2015). Mapping It Out: Expository Cartography for the Humanities and Social Sciences. University of Chicago Press. p. 40. ISBN   9780226217857. OCLC   905918505.

Further reading