太阳紫外辐射在大气中衰减的探讨

Attenuation of Solar UV Radiation in the Atmosphere

在对北京紫外辐射观测资料分析的基础上,提出了参与光化学反应的物质对太阳紫外辐射能量的吸收作用。计算表明北京地区1990年云天比晴天紫外辐射减少约为21Wm-2,此值与Cess等人的观测结果比较接近。这表明了大气中参与光化学反应的物质对光化辐射能量的吸收基本上等于云对太阳短波辐射的“异常吸收”之值。所以,在辐射传输模式、大气化学模式、气候模式中,应该考虑参与光化学反应的物质对光化辐射能量的吸收作用。

Based on analyzing observational data of solar ultraviolet radiation in Beijing area, the absorption effect of photochemical reactions in the atmosphere on solar ultraviolet radiation is carried out. Comparing to clear skies in 1990, the solar ultraviolet radiation decreased by about 21 W m-2 cloud skies in 1990, which is close to that observed by R. D. Cess et al. So, the anomalous absorption of solar radiation by clouds is basically equal to the absorption of solar actinic radiation by the substance with photochemical reactions in the atmosphere. The absorption in actinic band by all kinds of substances with photochemical reactions in the atmosphere should be considered in radiation transfer model, atmospheric chemistry model, and the climate model.