Tag: introduction to natural resources

Topography is a field of geoscience and planetary science comprising the study of surface shape and features of the Earth and other observable astronomical objects including planets, moons, and asteroids. 

The ozone layer is present in the stratosphere above the Earth. The layer is present at a distance of about 20-30 km away from the surface of the Earth. The layer of ozone is responsible for the absorption of the harmful Ultraviolet radiations from the solar radiations. These radiations are prevented from entering the Earth's atmosphere to prevent the development of skin cancer

• The ozone layer or ozone shield is a region of Earth's stratosphere which contains a high concentration of ozone ($O _3$) in relation to other parts of the atmosphere,
  
• The ozone layer acts as a filter for the shorter wavelength and highly hazardous ultraviolet radiation (UVR) from the sun, protecting life on Earth from its potentially harmful effects.
• Hence Ozone shields the earth from the harmful ultraviolet rays from the sun.
• So, the correct answer is 'Sun'.

The layer of the atmosphere closest to the earth is the troposphere also known as the lower atmosphere fixed composition of various constituents of air namely the carbon dioxide, nitrogen, ozone, rare gases etc, but the amount of water vapour varies from place to place and from time to time.

In the stratosphere, ozone molecules (three oxygen atoms) bonded together, prevent some of the Sun's most intense rays from reaching the Earth's surface. Currently, scientists and researchers worldwide are monitoring this layer; so thin at the South Pole, we call it a hole where the molecules are being very less.

Air is a bad conductor of heat and not a good conductor hence the temperature on the earth is maintained for life to exist unlike the other planets. Atmosphere prevents sudden increase in temperature during the day light hours. It slows down the escape of heat into outer space during the night.

The earth that we live on is one of the planets of the solar system. Its crust is deep and we stay on its uppermost layer. The upper layer of earth is formed by soil. It can get weathered away due to external forces like water, wind etc.