Latitudes And Longitudes (Social Studies / Geography)

Long back, it was believed that the Earth was flat. Pythagoras, a Greek philosopher, declared in the 6th century BCE that the earth is round; however, no one believed him. Later, it was proved that the Earth is spherical. Ferdinand Magellan sailed round the Earth in the 16th century thus proving that the Earth is spherical.

Since the Earth is spherical in shape, it can be challenging to locate a place on Earth. As a result, mapmakers came up with a system of imaginary lines (horizontal and vertical lines) to form a grid on maps and globes, which made it easier to locate a place.

Latitudes

Lines of Latitude are east-west circles (imaginary lines) that run parallel to the Equator. These lines become smaller as they reach the North Pole and the South Pole.

Equator is the 0˚ latitude and is an imaginary line that runs through the centre of the globe and divides the Earth into two halves – Northern Hemisphere and Southern Hemisphere.

The five important Lines of Latitude:

1. The Arctic Circle (66 1/2˚N)
2. The Tropic of Cancer (23 1/2˚N) in the Northern Hemisphere.
3. The Equator (0˚)
4. The Tropic of Capricorn (23 1/2˚S) in the Southern Hemisphere.
5. The Antarctic Circle (66 1/2˚S)

Longitudes or Meridians

Lines of longitude are known as Meridians; these lines are imaginary lines running from North to South on a globe or map and cross the Equator at right angles.

There are 360 meridians or lines of longitude. All meridians are of equal length. The distance between the longitudes is greatest at the Equator; the distance narrows as they move towards the Poles and converge at the Poles.

The meridian at 0˚ is called the Prime Meridian. This is also named as the Greenwich Meridian as it passes through a place called Greenwich in London.

Starting from the Prime Meridian, there are 180 meridians to the east and 180 to the west. The meridians at 180˚ E and 180˚ W are one and the same line. The International Date Line lies on this meridian.

Locating Places

The lines of latitudes and longitudes form a network of lines or grid on the globe/map. Using the latitude and longitude, we can find any place on the map/globe. The intersection of latitude and longitude lines provide the coordinates of a place.