Map Projections Vs Map Projection

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A map projection is defined as “a geometrical transformation of the earth’s spherical or ellipsodial surface onto a flat map surface.” Although many things have been written about these projections, people still find this subject to be one of the most contraversial aspects of map use. Many professionals admit that they don’t completely understand map projections. This shortcoming unfortunately can have consequenes. First, it hinders their abilty to understand to understand the international relationships in the global society. Second, it can make easy prey for poliatcians, advertisers, and others who lack understanding or use the map projections in deceptive ways.
There are an infinate number of map projections, and each is better suited for a particular purpose. So the question arises, how to distinguish one from another. Two approaches are commonly used to classify the projections into different families based on their geometrical distortion properties, realting to shape, area, and direction. Also examing the nature of the surface that is used to make the projection, whether it is a cone, plane or cylinder. These two aproaches go hand in hand with what spatial properties are preserved, also with the pattern and level of distortion.
The two projections that will be compared in this essay will be a cylindrical projection (Mercator), and a conic projection (Lambers equal area).
The first projection that will be analyzed will be the cylyndrical projection, dealing specificly with the Mercator projection. The most common to project accuratly is the equtrial zone, and frequently the only true useful aspect of all cylindrical projections. All of the coordinate lines are straight parallels. Cross meridians are always at right angles...

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...r British Columbia and it is also used by the United States Geological Survey or USGS and the United States Census Bureau.
Coordinates from a spherical datum can be made into an Albers equal-area conic projection with coordinates from the following formulas: Where λ is the longitude, λ0 is the reference longitude, φ is the latitude, φ0 is the reference latitude and φ1 and φ2 are the standard parallels.
The comparison of the Mercator and the Albers equal area projections is somewhat like comparing apples to oranges. They are both good at describing one region on the earth; however neither is good for displaying the entire globe. The problem with modern society is that the mental map, thanks to uneducated citizens, is that of the Mercator. So many individuals have a flawed sense of the mapped world. Hopefully with a more informed public this can change for the better.

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