The representation of the earth
- 2. THE REPRESENTATION OF THE EARTH The earth is spherical. However it is not a perfect sphere. It is slightly flattened at the poles
- 3. In the past, map making was a very slow process, involving observation and complex calculations and drawings. Modern maps are made using aerial photos and images from satellites orbiting the Earth. These images are put together to produce an exact picture of the Earth’s surface.
- 4. GLOBE A globe is a three-dimensional scale model of Earth (terrestrial globe or geographical globe). Represent the earth accurately, because they have a similar shape They do not contain detailed information
- 5. MAPS Maps are flat representations of the earth. They provide detailed information.
- 6. How do we locate places on maps?
- 7. We use the cardinal points to establish direction. The principal cardinal points are north, south, east and west. Some elements in nature can help us. For example, the sun rises in the east and sets in the west, and the North Star always indicates north. A compass is an instrument with a magnetic needle which always points north. A compass helps us find our way in a forest, at sea or even in a city if we get lost
- 8. MERIDIANS AND PARALLELS A series of imaginary vertical and horizontal lines enables us to identify the exact location of Places on Earth
- 9. MERIDIANS Meridians are semicircles which go from one pole to the other. The prime meridian (0º) (Greenwich meridian) is the point of reference for other meridians. It divides the Earth into two hemispheres: the western hemisphere and the eastern hemisphere.
- 10. PARALLELS Parallels are circles which are perpendicular to the meridians. The Equator is the most important parallel and is the point of reference for the other parallels. It is at the same distance from both poles. It divides the Earth into two hemispheres: the northern hemisphere and the southern hemisphere.
- 11. PARALLELS Other important parallels, from North to South, are: The Arctic circle The Tropic of Cancer The Tropic of Capricorn The Antarctic Circle
- 12. LATITUDE AND LONGITUDE Latitude and longitude indicate geographical coordinates: the exact location of a place on the Earth.
- 13. LATITUDE Is measured by using the parallels which start at the Equator (0º). At the poles there are 90º. They are north (N) or south (S).
- 14. LONGITUDE Is measured by using the meridians which start at the prime meridian (0º). They run vertically from 0º to 180º to the west (W), and 0º to 180º to the east (E). All locations on a line have the same longitude.
- 15. TIME ZONES Time Zones are a geographical world globe division of 15° each, starting at Greenwich, in England, created to help people know what time is it now in another part of the world.