The atmosphere around the earth acts as a glass wall of the green house. The CO2, Methane. N2O. CF. water vaporous etc. absorb the heat radiations and generate a specific atmospheric temperature (global temperature), i.e. the atmosphere is warmed by absorption of infrared thermal radiations (shorter wavelength radiant energy from the Sun and and convective heat fluxes from the surface). These gases in the atmosphere radiant energy. some of which towards the earth surface. This phenomena is termed as green house effect and these gases are called as green house gases.
