Question

(i) What is insolation?
(ii) Write a short note on the three parts of insolation.

Answer 1

Sun is the main source of energy and heat. It provides solar energy or fuel for the process of weather and climate. The energy emitted by the sun is known as solar radiation. The incoming solar radiation to the earth is known as insolation. Insolation consists of a bundle of rays of radiant energy of different wavelengths.

Considering the wavelength, insolation can be divided into three parts, they are:

1. Infra-red rays: These rays have long wave and largely absorber in the atmosphere.

2. Ultra-violet rays: The shortwave sun rays are called ultraviolet rays. This is the most hurtful ray of sun. The ozone layer protects us from these harmful rays of the sun.

3. Visible rays: The visible portion of the spectrum lying between the invisible ultraviolet and infrared rays, that most effectively heat the earth is visible rays of the sun. Because of the visible rays, we can see the objects on the surface of the earth.