FY-3A/MWHS辐射传递及冷空偏差修正

Radiance Transferfor FY-3A/MWHS and Space View Bias Correction

为了推进FY-3A/MWHS数据与国外同类载荷遥感数据的同化应用,针对FY-3A/MWHS业务L1数据尝试开展大气吸收通道在轨辐射校验,通过瞬时星下点交叉比对(SNO)方法,完成MWHS与美国NOAA卫星同类载荷AMSU-B轨辐射基准的交叉传递。两个同类载荷遥感数据的对比分析表明:MWHS大气水汽吸收线附近的主探测通道与AMSU-B对应通道天线亮温变化特征一致;以辐射校验为基础,可以将AMSU-B在轨辐射基准传递到MWHS冷空辐射修正量,实现微波探测器在轨辐射基准的归一化。辐射交叉校验技术,为两个同类微波探测器在轨遥感数据的融合应用以及在数值天气预报中多源数据的同化应用奠定了基础。

FengYun-3A(FY-3A),the first in a series of the second generation of polar-orbiting meteorological satellites of China,has been successfully launched on 27 th May,2008.The MicroWave Humidity Sounder(MWHS)is an important payload of FY-3A,which is for atmosphere sounding.FY-3A/MWHS has been operational application on orbit for more than 5years.In this paper,we try to make a cross validation for FY-3A/MWHS'radiance calibration on orbit,to make the guarantee for quantitative application of FY-3A/MWHS.NOAA-17/AMSU-B is the same kind of microwave radiometer with FY-3A/MWHS,and we make an extensive analysis between them to acquire the best fitted global SNO samples.Then the radiance basic reference of NOAA-17/AMSU-B has been cross transmitted to FY-3A/MWHS.Based on the cross calibration,we achieved the space view bias correction and using of the correction the bias between FY-3A/MWHS and NOAA-17/AMSU-B can be better well.The technique of radiance cross validation and the analysis results will be the basis for two sounders' remote sensing data application in NWP.