A Mercator map projection greatly distorts the area of land masses near the poles.
Explanation:
Mercator projection is a projection method where the meridians are deposited vertically on the parallel circles, and where the distance along these circles is gradually stretched more in relation to the terrain it gets closer to the pole. The method is common, for example on world and sea maps. It maintains directions correctly.
The projection gets right at the equator but in theory never reaches the poles and it depends on the cylindrical projection. Gerhardus Mercator's projection became famous in the 16th century and has since been used on the seas.
Wind erosion is the main cause. And since it is the desert that wind can pick up tiny sand rock particles that slowly grind against the rock. Over time the erosion will give a jagged rock the smooth features as if it had been submerged in a river for the roughly same period of time.
The Ming emperors made it their capital in 1421 and it remained China's capital till 1912 when the Manchu Empire fell and SunYat Sen turned China into a republic.
