在遥感数据定量应用中,卫星通道的光谱响应函数是影响定量产品反演算法、精度和获取的地球特征物理量的关键因素之一。针对FY-2E红外分裂窗通道光谱响应函数的调整,利用NOAA AVHRR卫星相应通道的定标查找表、青海湖实测的水面辐亮度和大气状态数据,以及利用PLANK方程模拟的全动态范围内的辐亮度等数据对FY-2E与FY-2C红外分裂窗通道的差异进行了深入分析,发现由于光谱响应调整导致通道的探测波段发生变化,将影响到卫星探测的下垫面物理特性反演。同时,由于对FY-2E光谱响应函数的调整,使其红外分裂窗通道的亮温差相对于FY-2C在整个动态范围内都明显的增加,将进一步提高FY-2E卫星红外分裂窗通道的定量反演能力。
Remote sensors’ channel spectral response function (SRF) was one of the key factors to influence the quantitative products’ inversion algorithm,accuracy and the geophysical characteristics.Aiming at the adjustments of FY-2E’s split window channels’ SRF,detailed comparisons between the FY-2E and FY-2C corresponding channels’ SRF differences were carried out based on three data collections:the NOAA AVHRR corresponding channels’ calibration look up tables,field measured water surface radiance and atmospheric profiles at Lake Qinghai and radiance calculated from the PLANK function within all dynamic range of FY-2E/C.The results showed that the adjustments of FY-2E’s split window channels’ SRF would result in the spectral range’s movements and influence the inversion algorithms of some ground quantitative products.On the other hand,these adjustments of FY-2E SRFs would increase the brightness temperature differences between FY-2E’s two split window channels within all dynamic range relative to FY-2C’s.This would improve the inversion ability of FY-2E’s split window channels.