敦煌地区晴空散射辐射影响因子的统计特征

The Statistical Characters of Influencing Factors of Diffuse Irradiance on the Clear Sky Days in Dunhuang Region

利用敦煌地区1981—1983年全年及1984年与1985年1～2月的日射观测资料,统计分析了敦煌地区晴空下散射辐射与太阳高度角、大气柱气溶胶垂直光学厚度等影响因子的关系,用最小二乘法拟合得到了相应的函数关系式。拟合结果表明:晴空下散射辐射与太阳高度角符合幂函数关系;晴空下散射辐射随大气柱气溶胶光学厚度线性增长。

Using the observed solar irradiance data in whole year of 1981\_1983 and the January to February of both 1984 and 1985, the variation of the diffuse irradiance on the clear days in Dunhuang region with the solar height angle, atmosphere optical mass and the aerosol optical depth were analyzed. A statistical relation was found by the last square method, it shows the variation of diffuse irradiance on clear sky days with the solar height angle coincides with power function, and the diffuse radiation on clear days increases linearly with the aerosol optical depth of atmospheric column.