利用RTTOV7快速辐射传输模式模拟风云二号红外和水汽成像通道辐射率的研究

为使RTTOV7能模拟FY2B红外、水汽通道辐射率,综合GENLN2计算的6个卫星天顶角的600-3000 cm-1的精确大气透过率,以及这两个通道的光谱响应函数,采用多元线性回归方法计算出适当的透过率系数.利用新的透过率参数,以相同的大气廓线作输入参量,对FY2B和GMS5的模拟分析表明,RTTOV7能得到相似的模拟亮温.利用ECMWF预报廓线以及新的透过率参数模拟FY2B水汽和红外亮温与实际观测的误差对比分析表明该模式能在短时间内以较高的精度模拟该卫星通道的辐射观测.

STUDY OF SIMULATION ON RADIANCE FROM INFRARED AND WATER VAPOR CHANNEL OF FY2B BY A FAST FORWARD MODEL-RTTOV7

In order to simulate the radiance of infrared and water vapor channels of FY2B with RTTOV,a multi-variables linear regression was used to produce transmittances by using spectral response functions of these channels and a precise transmittances database of 600-3000 cm~(-1) generated from GENLN2 at 6 viewing angles.When the same atmospheric profile and the new coefficients were put into RTTOV,simulation of FY2B and GMS showed that similar channel radiances were obtained.The comparative analysis of the deviation between the simulated radiances obtained with the profiles from ECMWF model forecast and the new coefficients for FY2B in RTTOV and the real observation for infrared and water vapor channels of FY2B indicate that the satisfying precise of radiances can be obtained within very short time.