Green House Effect
Out of the total solar radiation about 47% is absorbed at the earth surface. As a result the earth becomes hot and starts re-radiating long wave radiation. The exchange between the sky and the terrestrial radiation is largest governed by the atmospheric gases. The important principle is that the short wave lengths of the radiation’s from the sun can penetrate the atmosphere without being fully absorbed. These short radiation’s fall on ground, they heat it , and ground starts no- radiating long wages, The long waves emitted by the earth are absorbed in the atmosphere by water waves emitted by the earth are absorbed in the atmosphere by water vapour, CO2 and Ozone. On absorption of earth radiations these gases become warmer and in turn they again radiate the heat in still longer waves towards the earth This also increases the earth’s warmth.
The gases namely water vapour, CO2 and Ozone allows the solar radiations categorized as solar short waves to pass through the atmosphere towards the earth and not allow to escape the long waves radiations from the earth is known as green house effect.
This heat retaining behavior is similar to the roofed glass or green house used for experiment.
The atmospheric green house effect keeps the earth warm and does not allow its temperature to fall. The mean temp, of the earth is 150C since long and is maintained by green house effect.