晴天条件下基于FY-2E数据的地表短波净辐射的反演方法

Estimation of net surface shortwave radiation using FengYun-2E (FY-2E) data on cloud-free days

地表短波净辐射是辐射能量的重要组成部分.高时间、高空间分辨率的地表短波净辐射数据对长时间区域尺度气象变化和陆表水文循环等方面的研究具有重要意义.当前大多数遥感地表短波净辐射的研究基于极轨卫星观测数据,而利用高时间分辨率的静止卫星数据来反演多时相地表短波净辐射的研究则较少,更缺少日变化的地表短波净辐射产品.基于此,开展了基于中国静止气象卫星数据FY-2E的地表短波净辐射反演研究,并利用实测辐射观测数据对反演结果进行验证.结果表明:在晴天条件下,均方根误差(RMSE)为27.51 W/m^2,决定系数(R^2)为0.99;在除去冬季的晴天条件下,R^2为0.99,RMSE为15.36 W/m^2.该结果表明本文提出的地表短波净辐射反演方法具有较高的精度,适于长时间区域尺度气象变化等方面的研究.

Net surface shortwave radiation （NSSR） with high temporal and spatial resolutions is of great significance to studies of the Earth surface radiation budget, climate change, and some other relevant fields. However, most of the present investigations on the estimation of NSSR focus on the polar-orbit satellite observations which have only one or two images available for a given study area. This study primarily develops a method for obtaining NSSR by directly using the geostationary satellite data, and we provide multi-temporal NSSR estimates in regional scale using the Chinese operational geostationary meteorological satellite FengYun-2E （FY-2E） data. Results indicate a very significant correlation between our estimated NSSR and the tower-based NSSR measurements with the coefficient of determination （R^2） of 0.99 and a root mean square error （RMSE） of 27.51 W/m^2. The R^2 value is 0. 99 and RMSE is 15.36 W/m^2, excluding winter. This indicates that NSSR can be estimated by using the proposed method which benefits climate change and some other fields at the regional scale with high temporal resolution.