Map projections are an invaluable aspect of geography. The Earth is a 3-dimensional object and projecting it onto a 2-dimensional surface for navigation and other purposes is an integral part of mapmaking, since not carrying a 3-dimensional geography tool around is much less convenient than one of 2-dimensions. However, the application of map projections can be a double-edged sword if not used properly. In the case of equal-area map projections, areas are preserved at the cost of relative distance and angles. This type of projection is excellent for accurate representation of the surface area of the world's countries for political purposes but might not be the best choice for navigation. Between the Mollweide and Goode's homolosine projections, there is a discrepancy of roughly 2,000 miles between Washington, D.C. and Kabul.
Equidistant map projections preserve distance at the cost of area and angles. However, they only preserve distance from a central point or line and the further you deviate from that point or line, the less accurate the equidistant measurement really is. This type of map projection is useful in air route mapping, since it relies directly on distance. Between the equidistant conic and South Pole azimuthal equidistant projections, there is a discrepancy of approximately 100 miles.
Lastly is the conformal map projection. Conformal projections allow the preservations of angles locally, allowing the viewing of accurate shapes over small areas. Since the angles are preserved, conformal maps are best suited for navigational purposes. Between the Asia North Lambert conformal conic and North Pole stereographic projections, there is a difference of around 1,200 miles. Ultimately, the various types of map projections have their own advantages and disadvantages since there is no way to project a 3-dimensional map into a 2-dimensional surface without distortion. The trick to using map projections effectively is to know when and where to use each type of projection properly.
Equidistant map projections preserve distance at the cost of area and angles. However, they only preserve distance from a central point or line and the further you deviate from that point or line, the less accurate the equidistant measurement really is. This type of map projection is useful in air route mapping, since it relies directly on distance. Between the equidistant conic and South Pole azimuthal equidistant projections, there is a discrepancy of approximately 100 miles.
Lastly is the conformal map projection. Conformal projections allow the preservations of angles locally, allowing the viewing of accurate shapes over small areas. Since the angles are preserved, conformal maps are best suited for navigational purposes. Between the Asia North Lambert conformal conic and North Pole stereographic projections, there is a difference of around 1,200 miles. Ultimately, the various types of map projections have their own advantages and disadvantages since there is no way to project a 3-dimensional map into a 2-dimensional surface without distortion. The trick to using map projections effectively is to know when and where to use each type of projection properly.
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