Terrestrial radiation cooling

The cycle of birth and death of stars that is initiated by population III stars constantly increases the abundance of heavy elements in the interstellar medium, a crucial prerequisite for terrestrial (rocky) planet formation and subsequently for the origin of life (75). Metals dispersed in the interstellar gas or incorporated into micron-sized dust particles and molecules like CO and water, have the ability to cool the interstellar gas much more efficiently than molecular hydrogen does for population III stars. These elements and molecules are also excited through atomic and molecular collisions and their return to lower lying energy levels releases energy via far-infrared and sub-millimeter radiation below... 

Infrared radiative cooling of the Earth s stratosphere takes place through collisional excitation followed by radiative relaxation of molecular vibrational and rotational states, resulting in the emission of infrared and microwave radiation. In addition, these radiatively active molecules may intercept and reemit infrared radiation from the surface before it escapes to space. The result is a complex exchange of radiation between atmospheric layers and the surface. The effect of solar infrared radiation on this process is nearly negligible, since there is almost no overlap between solar and terrestrial blackbody surface emission. 

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