用GMS-5气象卫星遥测地面太阳总辐射

Observation of Solar Irradiance at the Surface from GMS-5

由GMS 5静止气象卫星测量的可见光通道的行星反照率 ,根据地球 大气系统的物理模式反演得到了地面的太阳辐射。该模式以平均气候模式和晴天的气溶胶光学厚度计算晴天的大气吸收、分子和气溶胶散射 ,其它情况下的散射由行星反照率和晴天的地表反照率推算而得。模式中考虑了水汽和气溶胶的变化对地表太阳辐射的影响。卫星反演的地表太阳辐射与地面观测结果的相关系数高达 95 %以上 ,日平均方差约为1 0 %。

Downward solar irradiance at the surface of the Earth is derived from the apparent satellite reflectance measurements from GMS 5 visible channel (0 4-1 1μm) based on a physical model of earth atmosphere system. The absorption and scattering of atmospheric molecule and aerosol on clear day are considered with standard mid latitude summer atmospheric model using the 6S, the scattering for other weather is abtained from the real time satellite albedo and the surface albedo acquired from the satellite measurements under clear sky condition. The effects of variations of aerosol and precipitable water on clear day to the surface solar irradiance are considered. Compared to the real time measurements by surface pyranometer, the correlation coefficient is as high as 95%, the deviation is about 10% of mean daily solar insolation. From the comparison, the accuracy of hourly solar irradiance estimated from GMS 5 in the text is improved.