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Map Projections 
Map Projection Pages


The following web pages on this web site contain extensive
information about map projections from U.S. Geological Survey documents. General Information



Cylindrical Map Projections
Cylindrical projections are used primarily for complete world maps, or for maps along narrow strips of a great circle arc, such as the Equator, a meridian, or an oblique great circle. In the normal (regular) aspect, meridians and parallels are straight lines. 
Regular 
Transverse 
Oblique 
Plate Carree (Geographic)
This widely used projection simply consists of plotting longitude and latitude points on an evenly spaced 

Equirectangular
A modification of the Plate Carree (Geographic) projection, with the meridians spaced closer together, forming rectangles with the parallels instead of squares. 

Cassini
The Cassini map projection is the transverse aspect of the Plate Carree projection. Equidistant. 

Mercator
The Mercator projection has area distortion, but is the only map projection that shows true compass bearings for navigation. Historically used in combination with the Gnomic. Conformal. 

Transverse Mercator
The transverse aspect of the Mercator projection, used to map quadrangles throughout the world. Conformal. 

Oblique Mercator
The oblique aspect of the Mercator projection, used to map regions having greater extent in an oblique direction, such as Hawaii and the Alaska panhandle. Conformal. 

Gall
A cylindrical projection used for world maps in British atlases. Looks like the Mercator, but takes up less space on the printed page. 

Miller Cylindrical
A cylindrical projection used for world maps in American atlases. Similar to the Gall. 

Cylindrical EqualArea
Easy to construct equalarea maps, used for education purposes. 

Pseudocylindrical Projections
Like the Regular Cylindrical projections, the Pseudocylindrical (or 
Interrupted Sinusoidal 
Robinson
Used for world maps. 

Eckert IV
Used for thematic and other world maps in numerous atlases and textbooks and for sheet maps. Equalarea. 

Eckert VI
Used for thematic world maps in the Soviet World Atlas of 1937. Some recent use for climatic maps by U.S. publishers. Equalarea. 

Sinusoidal
Used for world maps, and maps of continents and other regions especially those bordering the Equator. Used in atlases to map Africa and South America. Also used for interruptions (see above), transformations, and in combination with other projections. 

An equalarea projection of the Earth bounded with an ellipse. The basis of several other map projections. Example of interrupted form to show oceans. 

Goode Homolosine
Interrupted projection used for world maps. A merging of the Mollweide and Sinusoidal projections. Equalarea. 

Boggs Eumorphic
Based on the Mollweide and Sinusoidal projections. Equalarea. 

Wagner IV
A flat pole projection with equally spaced meridians as portions of semiellipses. 

Craster Parabolic
Used for thematic world maps in textbooks. Meridians are equally spaced parabolas intersecting at the poles. 

McBrydeThomas
FlatPolar Sinusoidal Projection. Basis of merged projections by McBryde. 

McBryde S3
World map interrupted to show oceans or land masses, by McBryde. 

Conic Projections
To show a region for which the greatest extent is from east to west in the temperate zones, conic projections are usually preferable to cylindrical projections. 
Equidistant Conic
The most common projection in atlases for small countries. It was also used to map the Soviet Union. 

Albers EqualArea
One of the most commonly used projections for maps of the conterminous United States. 

Lambert EqualArea Conic
A conic projection with one standard parallel, and the pole as a point. 

Lambert Conformal Conic
Used for largescale mapping of regions of predominantly eastwest extent, including topographic quadrangles for many of the U.S. State Plane Coordinate System zones. 

Bipolar Oblique Conic Conformal
Shows North and South America in one map. 

Polyconic
The Polyconic projection shows meridians curved, not straight 

Bonne
A pseudoconic projection, popular in atlases for maps of continents until the 

Werner
Used in the 16th and 17th centuries. Mathematically similar to the Bonne. 

Azimuthal Projections
While cylindrical and conic projections are related to cylinders and cones wrapped around the globe, the azimuthal projections are formed onto a plane which is tangent to the globe. Azimuthal Projections Overview by John P. Snyder, U.S. Geological Survey 
Polar 
Oblique 
Perspective Azimuthal Projections:


Orthographic
The Earth as viewed from deep space. 

General Vertical Perspective
The Earth as viewed from near space (for example, as viewed from the position of a satellite). Perspective. 

Stereographic
Used to map polar regions, and large continentsized areas that extend similarly in all directions. Also has many other applications. 

Gnomonic
Also called the “Gnomic,” it diplays all great circles as straight lines, showing the shortest distance between any two points. All great circles are shown as straight lines, not merely those passing through the center of the projection. Historically used for navigation. Perspective. 

Nonperspective Azimuthal Projections: 

Lambert Azimuthal EqualArea
Areas are correct, and the overall scale variation is less than that found on the major perspective azimuthals. 

Azimuthal Equidistant
Distances from the center of the projection to any other point are shown correctly. Overall scale variation is moderate compared to the perspective azimuthals. Equidistant. 

Airy
The mimimumerror azimuthal projection of the region enclosed by a great or small circle of chosen radius from a given center. Nonperspective, neither conformal nor 

Modified Azimuthal Projections: 

Hammer (HammerAitoff)
Used for wholeworld maps. Less shearing on the outer meridians near the poles than there is on pseudocylindrical projections. 

Winkel Tripel
Also used for wholeworld maps. 

Wagner VII
A modification of the Hammer projection. Used for world maps, such as climatic maps prepared by the U.S. Department of Commerce. 

EckertGreifendorff
Wholeworld map, derived from the equatorial aspect of the Lambert Azimuthal EqualArea projection. 

Briesemeister
Whole world maps showing continents grouped near the center. Derived from the oblique aspect of the Hammer projection. 

Miller Oblated Stereographic
Used for areas that can be contained within an oval shape to minimize the scale distortions in the area. Conformal. 

TwoPoint Azimuthal
A geometric tilting of the Gnomonic. Rarely used, but can be used to find the location of a ship at sea with a radio direction finder and known locations of radio transmitters. 

TwoPoint Equidistant
Shows true distances, but not true azimuths, from either of two chosen points to any other point on the map. Has received moderate use and interest. 

Van Der Grinten
The world enclosed in a circle. 

Space Oblique Mercator
Suitable for mapping imagery from Landsat and other vertically scanning satellites. 

Satellite Tracking
Also for mapping the groundtrack of orbiting satellites. Cylindrical or Conic 

GS50 Projection
Mathematical projection for displaying the U.S. with minimal distortion. Developed by John P. Snyder. 

Armadillo Projection
Most of the world, projected onto a portion of a torus ring (similar to a doughnut). 

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