Abstract: A two stream model has been used to calculate the variation of optical depth and their effects to ultraviolet radiation of each extinction material. With the model, the relation among season, solar zenith angle and ultraviolet radiation has been discussed, and the variation of ultraviolet radiation under different clouds has also been studied. The comparative research of ultraviolet radiation among Kunming, Beijing and other abroad area at the same latitude has also been done.

Key words: ultraviolet radiation, two stream model, optical depth

摘要： 在已建立的计算昆明紫外辐射两流模式改进的基础上，进一步计算并讨论了：(1) 各种消光物质的光学厚度变化规律及其对紫外辐射的影响；(2) 季节变化及太阳天顶角变化与紫外辐射的关系；(3) 不同云的光学厚度下紫外辐射的变化；(4) 昆明与北京两地模式计算结果比较，以及与国外相近纬度观测结果进行了比较。

关键词: 紫外辐射, 二流模式, 光学厚度