Infrared radiative properties of cirrus clouds in shortwave spectral region

DISORT method was employed to study radiative properties of cirrus clouds in the shortwave infrared spectral region. The properties were shown, as well as their dependence on wavelength, visible optical thickness of cirrus clouds, cloud altitude, the particle shapes and effective size of cirrus clouds, and so on. The influences of cirrus clouds on atmospheric infrared background radiation were analysed. The main result is that at 2.7 μm atmospheric absorption region, the atmosphere background radiance is very weak, but when cirrus clouds appear in the sky, they reflect solar energy, thus the atmosphere background radiance is greatly enhanced.