The effects of changes in wavelength and ambient conditions on the atmospheric backscatter at CO2 wavelengths have been examined. It has been found that, with the exception of (NH4)2SO4-containing aerosols, whose size distributions have relatively large numbers of small particles, the variation of backscatter with CO2 wavelength is less than a factor of ~3. However, for such (NH4)2SO4 aerosol distributions, the variation of backscatter function with CO2 wavelengths between 9.1 and 11.1 µm may reach 1 order of magnitude. The effects of ambient humidity and temperature changes are negligibly small when the relative humidity is low (<75%). However, for a humid environment (>90%), a few percent change in humidity or a few degrees change in temperature may cause noticeable change in backscatter from aerosol particles of small sizes.
© 1983 Optical Society of America
Glenn K. Yue, G. S. Kent, U. O. Farrukh, and Adarsh Deepak, "Modeling atmospheric aerosol backscatter at CO2 laser wavelengths. 3: Effects of changes in wavelength and ambient conditions," Appl. Opt. 22, 1671-1678 (1983)