Greenhouse effect in the atmosphere

Average optical atmospheric parameters for the infrared spectrum range are evaluated on the basis of the Earth energetic balance and parameters of the standard atmosphere. The average optical thickness of the atmosphere is and this atmospheric emission is originated at altitudes below 10 km. Variations of atmospheric radiative fluxes towards the Earth and outward are calculated as a function of the concentration of molecules for the regular model of molecular spectrum. As a result of doubling of the concentration the change of the global Earth temperature is if other atmospheric parameters are conserved compared to the value under real atmospheric conditions with the variation of the amount of atmospheric water. An observed variation of the global Earth temperature during the last century follows from an increase of the mass of atmospheric water by 7% or by conversion of 1% of atmospheric water in aerosols.