Globe: Latitude Longitude
Globe: Globe is a miniature model of the earth. Globe is fixed between two pivots. It can be rotated around the pivots. Globes come in different shapes and sizes. Globes can be very big or can be very small in size. Inflatable globes are also available.
Globe is very useful while studying about the earth.
The top and bottom of the earth are called the Poles. They are similar to the top and bottom of the globe. The top is called the North Pole and the bottom is called the South Pole.
The way a glove rotates around the pivots, the earth also rotates around an imaginary line. The imaginary line around which the earth rotates is called the axis of the earth.
An imaginary line passes horizontally from the middle of the earth’s surface. This line is called the equator. The equator divides the earth into two equal halves. The northern half is called the Northern Hemisphere. The southern half is called the Southern Hemisphere.
Parallels of Latitudes
All parallel circles from equator up to the poles are called parallels of latitude. Latitudes are measured in degrees.
Degree of Latitudes
The equator shows the zero degrees latitude. The distance from the equator to either of the Poles is one fourth of a circle around the earth. Hence, this distance is equal to one-fourth of 3600, i.e. 900. So, the latitude of the Poles is 900. The latitude of the North Pole is 900 north and that of the south Pole is 900 south.
The value of each latitude is followed by the words north, or south or N or S. All parallels to the north of the equator are called north latitudes. Similarly, all parallels to the south of the equator are called south latitudes. For example; the latitude of Delhi is about 280N.
Important Parallels of Latitudes
Apart from the equator (00) and the Poles (900); there are four important parallels of latitudes. They are as follows:
- Tropic of Cancer 23.50 N (230 30’N) or 23 degrees 30 minute north
- Tropic of Capricorn 23.50 S (230 30’S) or 23 degrees 30 minute south
- Arctic Circle 66.50 N (660 30’N) or 66 degrees 30 minute north
- Antarctic Circle 66.50 N (660 30’N) or 66 degrees 30 minute south
Fig: Important Parallels
The Tropic of Cancer and the Arctic Circle are present in the Northern Hemisphere. The Tropic of Capricorn and the Antarctic Circle are present in the Southern Hemisphere.
Heat Zones of the Earth
Between the Tropic of Cancer and the Tropic of Capricorn, the mid-day sun is exactly overhead at least once in a year on all latitudes. This happens because the sun rays come straight to these latitudes at least once in a year. So, this part of the earth receives the maximum heat from the sun. This zone is called the Torrid Zone.
Beyond the tropics, the mid-day sun is never overhead. This happens because the sun rays come at a slant in these areas. So, this part of the earth receives mild temperature. These zones are called the Temperate Zones.
Areas between the Arctic Circle and the North Pole and those between the Antarctic Circle and the South Pole receive sun rays at a big slant. Due to this, the sun is never much above the horizon. So, this part of the earth receives the least amount of heat and remains very cold. These zones are called Frigid Zones.