A phenomenon in which the atmosphere of a planet traps radiation emitted by its sun, caused by gases such as carbon dioxide, water vapor, and methane that allow incoming sunlight to pass through but retain heat radiated back from the planet's surface.
Figure 3. The greenhouse effect. Solar short-wave radiation (light) entering the atmosphere is absorbed by the Earth’s surface and emitted as long-wave infrared radiation (heat) that is then absorbed by greenhouse gases which heats the atmosphere.[fn][[nid:327]][/fn]