Both of these two maps are projections of the world. However, if you look at it closely, Antarctica on the geographic coordinate system map (top map) is being stretched out compare to Antarctica on Mercator projection map (lower map). However, the map below is not necessarily accurate either because it looks like Antarctica is the size of the world.
Mercator projection was first invented by a Flemish geographer and cartographer Gerardus Mercator in 1569. Ever since then, Mercator projection became the standard map projection. The linear scale of this projection is constant in all directions around any point. While it preserve all points in all directions, Mercator projection distorts size and shape of the object, which explains why Antarctica became augmented.
The difference between GCS and Mercator projection is that GCS uses coordinate system that involves directions in reference to longitude, latitude, and elevation. While Mercator projection also has these intersecting lines that can be used as coordinates, the directions used in GCS may not be able to be accurately applied to Mercator projection because the Mercator lines intersect at a 90 degree angle while GCS projection does not.
Equidistant Maps
Equidistant Conic Map (top map) have a distinctive feature than other projection. The meridians are straight equidistant lines, converging at a point which may or not be a pole. The parallels arcs of circle is concentric in the point of convergence of meridians. Distortion is constant along each parallel lines not touching the cone. This projection preserves distance between any two points on the map. Conic projections are favored for national maps of temperate zones like Russia or the United States. However, conic projections are seldom appropriate for world maps.
Like Equidistant Conic Map, Sinusoidal Map (lower map) also preserves distance between any two points on the map. Sinusoidal projection shows relative sizes accurately, but distorts shapes and directions. The feature of this map is the same everywhere at the central meridian, and the east-west scale is throughout the map the same as that. This map is made in reference to the latitude, longitude, and the central meridian as the central reference point intersection.
Equal Area Maps
Gall Orthographic (top map), named after James Gall, is a configurable equal area map projection known as the equal area cylindric projection. This projection preserves area everywhere on the map. This projection however, suffers extreme distortion in the polar regions, as any cylindrical projection must, and its distortion along the equator is considerable. The map feature is overly stretch vertical ways, which causes the distortion at both poles. This map is made by inflating the sizes of regions according to their distance from the equator.
Mollweide (lower map) is a pseudocylindrical map projection generally used for global maps of the world. Like Gall Orthographic, this map preserves the area everywhere on the map. The proportion of the area of the ellipse between any give parallel and the equator is the same as the proportion of the are on the globe between that parallel and the equator. However, this is at the expense of shape and angle distortion, which is significant at the perimeter of the ellipse. Unlike the other projection, the map features an ellipse with all the longitude line emerging towards the poles but never actually meet to intercept at the poles. Constructing this map requires careful analysis of each parallel and perpendicular lines. Mollweide is a projection in which the equator is represented as a straight horizontal line perpendicular to a central meridian one-half its length. The other parallels compress near the poles, while the other meridians are equally spaced at the equator.
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