Ways to represent the Earth

Cartographers are people specialiced in drawing maps. They thought a way to the spherical image of our planet in a flat surface: the maps. A map is a graphic representation of an area of the surface of the Earth, shown from above and to scale. They show mountains, rivers, cities, roads... As an exact projection of a spherical surface on a flat surfacce is impossible, a few types of map projections have been devised in order to solve this difficulty, There are a lot of map projections, but we are just mentioning some of them:

- The polar projection is a projection drawn to shor Artic and Antartic areas. It is based on a plane which is perpendicular to the Earth's axis in contact with the North or South Pole.

- The Mercator projection is a cylindrical map projection in which areas turn larger and larger as you move away from the equator.

- The Fuller map is a projection of a world map onto the surface of a polyhedron, which can be unfolded to a net in many different ways and flattened to form a two-dimensional map which retains most of the relative proportional integrity of the globe map. It shows our planet without any visible distrotion of relative shapes and sizes of the land and the sea areas, and without any breaks in the continental contours.

- Globes are more accurate than maps for representing the Earth because they are three-dimensional like the Earth itself. When you try to reproduce the sufrace of the Earth on a flat map, the sizes and shapes get distorted.

THE SPHERES OF THE EARTH

The Earth is the only planet in the Solar System that can support life. The sphere of the planet where life exists is called biosphere. The three spheres which support life on Earth are the atmosphere, the hydrosphere and the geosphere.