Atmospheric gases play a role in planetary temperature regulation Carbon dioxide levels have been rising rapidly in the Earth’s atmosphere and are linked by the IPCC to “global” warming. Recent failure of measured temperatures to advance with increasing carbon dioxide has called this assertion into question. Part of the problem has come from the term absorption. The coupling of a photon with an atmospheric gas molecule is better described as a liaison, a brief union that ends with the directionally random (Lambertian) dissociation of the photon. No atmospheric energy is added. The dry, dust-free troposphere remains adiabatic. The photon is simply redirected. Effects on temperature depend on the change in direction of the liaison photon. The model used by climatologists commonly assumes that all photons involved in the radiation balance originate from the Earth’s surface and are deflected back to the Earth, causing warming. But people from the same general discipline who are focused on stratospheric gases and their concentrations recognize that radiation from the stratosphere itself is also based on the same fourth power of temperature. http://www.atmos-chem-phys-discuss.net/7/11561/2007/acpd-7-11561-2007-print.pdf They use GENSPECT to analyze the stratospheric chemical levels assuming black body emissivity. Other models like MODTRAN fail to incorporate stratospheric downward thermal radiation. Downward photons arising from the warm upper stratosphere are affected oppositely by the liaison process and sent into space by scattering, counteracting the effect of the same gas on upward radiation. Overall loss is much less influenced by greenhouse gas concentration than IPCC models indicate. This is why Earth’s temperature is not rising as predicted. An important modeling need is knowledge of emissivity. Black body means an emissivity of 1.0. Stefan used this value in calculating the temperature of the Sun not long after his 1879 paper. Stratospheric chemical analysts using infrared also make this assumption to at least 35 km altitude. Many experimentalists have generated tables of values for a broad array of materials http://www.omega.com/literature/transactions/volume1/emissivity.html http://www.engineeringtoolbox.com/emissivity-coefficients-d_447.html Most values are below 1.0, some fairly strikingly. Some Earth surface outward radiation models use experimental numbers rather than 1.0 http://www.gisdevelopment.net/technology/rs/ma03196.htm . Emissivity is not always near 1.0. In the solar system, the Sun’s corona has an emissivity on the order of 10-10. Its very low density limits its radiation intensity. Beyond this example, we know little about the effect of density on emissivity. But if the emissivity of the Earth’s thermosphere is more than 10-4 all current Earth radiation balance models are seriously erroneous. By the way, the 50 km top of the stratosphere has a mass density the same as the Sun’s photosphere. http://en.wikipedia.org/wiki/Earth's_atmosphere http://www.madsci.org/posts/archives/2001-05/988762969.As.r.html The need to link emissivity to density is clear. Emissivity must fall somewhere above the top of the stratosphere. There is an unusual reward for this new understanding. Density may be expressed as mass or atoms/molecules per unit volume. Planck-Stefan-Boltzmann radiation is a basic property of matter. All matter above absolute zero radiates photons to the universe if they can find their way. Is this a consequence of mass or existence?