Earth ozone layer due to the subsequent conversion of atmospheric into. The ozone layer blocks ultraviolet solar radiation, permitting life on land. Other atmospheric functions important to life include transporting water vapor, providing useful gases, causing small meteors to burn up before they strike the surface, and moderating temperature. This last phenomenon is known as the greenhouse effect: trace molecules within the atmosphere serve to capture thermal energy emitted from the ground, thereby raising the average temperature. Water vapor, carbon dioxide, methane, nitrous oxide, and ozone are the primary greenhouse gases in the atmosphere. Without this heat-retention effect, the average surface
Idealized greenhouse model for the required amount of heat energy finally to be radiated out into space from the top of the atmosphere. The greenhouse effect can be illustrated with an idealized planet. This is a common "textbook model": the planet will have a constant surface temperature T and an atmosphere with constant temperature T. For diagrammatic clarity, a gap can be depicted between the atmosphere and the surface. Alternatively, T could be interpreted as a temperature representative of the surface and the lower atmosphere, and T could be interpreted as the temperature of the upper atmosphere. In order to justify that T