Greenhouse gases

(i) The gases present in the atmosphere that trap the sun’s heat and are responsible for the heating of earth’s atmosphere are called greenhouse gases. E.g. Methane, CO₂ etc.

(ii) These gases are responsible for the greenhouse effect. The sunlight contains infrared radiations which are responsible for the heating. Earth reflects the radiations back into the atmosphere but not all the radiations escapes as some part of it is absorbed by the greenhouse gases.

(iii) This helps in maintaining a hospitable temperature of the earth’s surface (average temperature being 15⁰C) as it provides balance in the temperature during day and night.

(iv) But recently due to excessive pollution and releasing of CO₂ and other greenhouse gases in the atmosphere, more heat is being trapped in the atmosphere leading to an overall increase in the temperature of the Earth known as Global Warming.