The gases found in the atmosphere like carbon dioxide, water vapor, methane, nitrous oxide, chlorofluorocarbons are responsible for the greenhouse effect on the earth. These gases allow short – wave radiations from the sun to enter into the earth, s atmosphere but reflect the long wave radiation, particularly infrared rays, emitted from the earth and send them back to the earth. As a result, the earth’s surface is getting warmer continuously.
This effect is called the Greenhouse Effect.
Status of Greenhouse Effect: In extreme cold regions, where the amount of insolation is usually low in winters, there the greenhouse effect is used to produce fruits and vegetables. The main feature of green houses is their glasses, through which the sunlight gets in, but the radiation in the form of long waves from the earth cannot go out of these houses. As a result, the temperature inside the houses increases. The status of atmosphere on the earth is similar to that of green houses.
Greenhouse Gases: Water vapor keeps the earth warm in the natural form. But due to human activities, the gases like carbon dioxide, methane, nitrous oxide, chlorofluorocarbons, etc. are creating the greenhouse effect on the earth. These gases are also called the ‘Green House Gases’. Carbon – dioxide is the major gas in the greenhouse effect. There is a constant increase in its amount in the atmosphere.
Composition of Greenhouse Gases: Carbon – dioxide contributes 57% in the green house effect, methane contributes 18%, nitrous-oxide contributes 6% and chloro – fluoro – carbons contribute 17%. Adverse Consequences of Greenhouse Effect: Due to the temperature increase, the greenhouse effect adversely affects the biotic, abiotic, social, cultural and economic conditions on the earth’s surface.
Its adverse effects can be explained as follows:
1. Increase in temperature: Increase in temperature of the earth is a major harmful consequence of the greenhouse effect created by humans. Increase of greenhouse gases in the atmosphere is a main cause of it. There will be many climatic changes on the earth due to increase in temperature. The discrepancies in weather are the result of this.
2. Increase in rainfall: Due to the increase in temperature on the earth, there will be more evaporation from the aquatic parts. Consequently, there will be more rainfall.
3. Melting of snow at the poles: Due to the increase in temperature on the earth, there will be melting of snow at the poles and mountain peaks.
4. Rise in water level of sea: The water level of sea will rise by the melting of snow at the poles and mountain peaks due to the increase in average temperature of the world. As a result, many coastal areas will be submerged in water.
5. Effect on Agriculture: Agriculture will also be affected by the change in the volume and periodicity of rainfall.
6. Effect on living organisms and vegetations: The living organisms that have less ability to withstand the heat will be destroyed. With the increase in sea level, the vegetation of coastal parts will be submerged.
