appendix b global climate change and maryland the amount of sun s radiative heat that is trapped in earth atmosphere a key determinant planet overall there are many factors control how much this either reflected or re radiated into space including magnitude solar radiation concentration particles reflect block incident such as aerosols cloud cover greenhouse gases ghgs virtually transparent to sunlight shortwave allowing it pass through air surface absorbs emits thermal longwave back because not outgoing some absorbed heats turn both outward downward further warming balance energy enables maintain enough warmth support life without natural effect would be approximately 55 f colder than
