Abstract: The basic formulas of the emission and transmission for non-local thermodynamic equlibrium(NLTE)planetary atmospheres are derived.By assuming that rotational levels within a vibrational level remain in thermodynamic equilibrium,an accurate and efficient line-by-line algorithm of NLTE emission and transmission is developed to evaluate the radiance due to infrared active species in the upper planetary atmospheres.The limb viewing spectral radiance,line integrated radiance,band integrated radiance and synthetic spectral radiance of the Earth's atmosphere for the 9.6μm bands of ¹⁶O₃ under daytime and nighttime and under NLTE and LTE conditions are calculated by using this algorithm.The results of calculations reveal that NLTE radiance obviously departs from LTE.

Key words: non-local thermodynamic equilibrium(NLTE), emission and transmission, radiance and transmittance, line-by-line algorithm