摘要: RAND weather data tapes have been used to obtain statistics of visibility, relative humidity and cloud ceiling heights for weather stations throughout the Northern Hemisphere to generate global probabilities for atmospheric attenu... 展开 RAND weather data tapes have been used to obtain statistics of visibility, relative humidity and cloud ceiling heights for weather stations throughout the Northern Hemisphere to generate global probabilities for atmospheric attenuation in the infrared spectral region. The present analysis predicts seasonal probabilities for horizontal sea level transmission losses for several narrow IR bands (1.0-1.2), (3.8-4.2), (8.0-11.5 micrometers) and four laser lines (1.06), (3.83), (4.73) and (10.6 micrometers). The results also include cloud-free-line-of-sight probabilities and attenuation losses through rain. (Author) 收起