Area Distortion by a Projection

The Mercator projection does not preserve areas. It is not an equal-area projection.

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GeoProjectionData["Mercator", "EqualArea"]

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The area of Africa is more than 14 times larger than the area of Greenland.

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GeoArea[Entity["GeographicRegion", "Africa"]]/ GeoArea[Entity["Country", "Greenland"]]

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In a Mercator map, however, Africa and Greenland seem to have similar sizes.

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GeoGraphics[{GeoStyling[Green], Polygon[Entity["Country", "Greenland"]], GeoStyling[Red], Polygon[Entity["GeographicRegion", "Africa"]]}, GeoProjection -> "Mercator", GeoRange -> "World", GeoBackground -> "Satellite"]

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Use an equal-area projection, like Mollweide, to represent more appropriately the relative sizes.

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GeoProjectionData["Mollweide", "EqualArea"]

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GeoGraphics[{GeoStyling[Green], Polygon[Entity["Country", "Greenland"]], GeoStyling[Red], Polygon[Entity["GeographicRegion", "Africa"]]}, GeoProjection -> "Mollweide", GeoRange -> "World", GeoBackground -> "Satellite"]

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