Study of the 10 micron continuum of water vapor

Radiation attenuation by atmospheric water vapor is considered. A formula based on laboratory data is recommended for approximating continuous absorption in the spectra region in question. Data of full scale measurements and laboratory experiments are compared. It was concluded that only molecular absorption need be taken into account under clear atmospheric conditions during the warm part of the year, while in winter or in cloudy conditions, the effect of aerosol can be significant

CO2 - LASER RADIATION ABSORPTION IN 1000 CM-1 WATER VAPOR CONTINUUM

Water vapor absorption of CO2-laser radiation at R 40, R 10, P 20, P 32 lines of the 10.4µ band and R 10, R 18, R 44 lines of the 9.4µ band has been investigated in the laboratory. The results obtained are compared with the measurements of 10-13µ solar radiation attenuation. The experimental facts strongly support the assumption that water dimers play an important role in the 8-13µ region. The analysis of field and laboratory experiments allow the following conclusion : under most meteorological conditions occuring in a cloudless atmosphere the continuum absorption by water vapor must be taken into account in the CO2 - laser radiation absorption. Estimates of the attenuation can be successfully obtained by making use of approximate expressions deduced from the laboratory data