Question

The atmosphere of the earth is heated by radiations which are mainly

• A. radiated by the sun
• B. re-radiated by land
• C. re-radiated by water
• D. re-radiated by land and water

Answer 1

The correct option is D

re-radiated by land and water

Explanation for the correct option:

In the case of option D.

1. Greenhouse gases are atmospheric gases that absorb heat, and then re-radiate the heat. The process of continual absorbing and radiating creates a cycle that retains heat in the atmosphere; this cycle is called the greenhouse effect. Carbon dioxide and chlorofluorocarbons are examples of greenhouse gases.
2. The earth absorbs radiation from the sun and then tries to transmit it back to the atmosphere.
3. But the atmosphere absorbs very selective gas as a result of which the gas radiated gets back to earth resulting in an increase in temperature.
4. When solar radiations fall on earth, some are absorbed by the land but the majority of these are reflected back or re-radiated by land and water bodies.
5. This re-radiated or reflected solar radiation heats up the atmosphere.
6. The amount of heat re-radiating from any area of Earth’s surface is influenced by many factors, including how much solar radiation is absorbed in that location.
7. Some of the heat is re-radiated by Earth’s surface and the atmosphere is lost back to space.

Thus, the correct option is option D.