This trait is useful when illustrating phenomena that depend on latitude, such as climate. The type of projection and the properties preserved by the projection use the following categories: There are many different ways of display the geography of the world, with the Robinson and Mercator projections amongst the most popular.
The north to south stretching equals east to west but grows with latitude faster than east to west stretching in the case of central cylindrical projection. North-south distances neither stretched nor compressed 1: Examples of pseudoconic projections include "bonne", which is an equal-area map projection.
Examples of conic maps include equidistant, Albers, and Lambert conformal conic. A surface that can be unfolded or unrolled into a plane or sheet without stretching, tearing or shrinking is called a developable surface.
In the second case central cylindricalthe north-south scale exceeds the east-west scale everywhere away from the equator. Azimuthal In standard presentation, azimuthal projections map meridians as straight lines and parallels as complete, concentric circles.
Spherical models are useful for small-scale maps such as world atlases and globes, since the error at that scale is not usually noticeable or important enough to justify using the more complicated ellipsoid. Cylindrical projections can be either equal-area, conformal, or equidistant.
Rotations are normally ignored for the purpose of classification. The ellipsoidal model is commonly used to construct topographic maps and for other large- and medium-scale maps that need to accurately depict the land surface.
Pseudoazimuthal In standard presentation, pseudoazimuthal projections map the equator and central meridian to perpendicular, intersecting straight lines.
This applies for the Mercator projection in normal aspect. The projections are described in terms of placing a gigantic surface in contact with the earth, followed by an implied scaling operation. However, map projections have distortions which depend largely on the size of the area being mapped.
Map projections are important in creating maps with map projections distorting the surface in some way. Since this projection scales north-south distances by the reciprocal of east-west stretching, it preserves area at the expense of shapes.
Combination of the above: Such a cylindrical projection for example is one which: In large-scale maps, Cartesian coordinates normally have a simple relation to eastings and northings defined as a grid superimposed on the projection.
Each projection preserves, compromises, or approximates basic metric properties in different ways. Pseudocylindrical projections represent the central meridian as a straight line segment.
Notable lines[ edit ] The developable surface may also be either tangent or secant to the sphere or ellipsoid.
Instead the parallels can be placed according to any algorithm the designer has decided suits the needs of the map. The maps are not constrained to rectangles or discs.
The projections stretch from east to west according to their geometric constructions and are the same at any chosen latitude. The following sections describe and illustrate how the cylindrical, conic, and azimuthal families of map projections are constructed and provides some examples of projections that are based on them.
To compare, one cannot flatten an orange peel without tearing and warping it. Van der Grinten projection preserves the image of Mercator projection and reduces its distortion. Unlike conic projections, the meridian is not constrained to be a straight line.
If you rotate the globe before projecting then the parallels and meridians will not necessarily still be straight lines.
However, the Polar Regions can still be distorted by the Van der Grinten projection. The cylindercone and the plane are all developable surfaces. Hence other peer categories have been described in the literature, such as pseudoconic, pseudocylindrical, pseudoazimuthal, retroazimuthal, and polyconic.
Scale Distortions On Map Projections Map projections without distortions would represent the correct distance, direction, shapes, and areas on a map.The ways in which we visualize the world are varied- we have pictures, maps, globes, satellite imagery, hand drawn creations and more.
What kinds of things can we learn from the way we see the. Map projections are attempts to portray the surface of the earth or a portion of the earth on a flat surface. Some distortions Texas State-Wide Map Projection. types of map projections and their characteristics, with examples given using maps from the GIS Research & Map Collection, University Libraries.
74 rows · List of map projections. Jump to navigation Jump to search This list provides an overview of some of the significant or common map projections. Because there. Learn about the different types of map projections and the different projection techniques that mapmakers use, including the Mercator projection.
Most map projections can be categorized The Three Main Families of Map Projections These are based on the types of geometric shapes that are used.Download