FY-3A微波资料偏差订正及台风路径预报应用  

Bias Correction for FY-3A Microwave Sounding Data with Its Application to Typhoon Track Forecast

作　　者：杜明斌[1,2] 杨引明[3] 杨玉华[4] 张洁[2] 朱雪松[2] 

机构地区：[1]南京大学,南京210093 [2]上海市卫星遥感与测量应用中心,上海201100 [3]上海中心气象台,上海200030 [4]中国气象局上海台风研究所,上海200030

出　　处：《应用气象学报》2012年第1期89-95,共7页Journal of Applied Meteorological Science

基　　金：国家自然科学基金项目(41001283);公益性行业(气象)科研专项(GYHY200906002)

摘　　要：我国极轨气象卫星FY-3A大大增强了对地球系统的综合探测能力,而偏差订正对卫星资料的应用非常必要。试验中FY-3A卫星微波资料的偏差订正方案是在Harris等的TOVS辐射资料偏差订正经验方法的基础上结合WRF-3DVAR系统发展的,偏差订正后微波资料各通道拟合结果基本位于主对角线上,大多数卫星观测数据与观测算子利用背景场计算的亮温值分布趋于合理,偏差得到很大程度的降低。偏差订正后,利用数值模式直接同化FY-3A气象卫星微波资料,通过对2008年和2009年的4个台风进行预报评估表明:同化FY-3A气象卫星资料后路径预报能力提高明显,尤其是36 h后路径预报结果;同化FY-3A气象卫星微波资料后台风预报路径误差平均降低20%,而只同化常规资料路径误差仅仅降低了4%。The quality of numerical weather prediction depends closely on accuracies of initial condition provided by observation system.Satellite observations are very important source for data assimilating models, which is of good overcast,high resolution and stable,improving prediction compared to conventional data in many cases.A new generation polar-orbiting meteorological satellite of China,FY-3A is successfully launched on 27 May 2008,and FY-3B is also successfully launched on 5 November 2010.The two kinds of microwave vertical sounding sensors aboard are very similar in capability to ATOVS（the Advanced TIROS Operational Vertical Sounder） of NOAA series satellite.One of them is microwave temperature sounder （MWTS）,and the other one is microwave humidity sounder（MWHS）.They are used to sound the vertical distribution of the atmospheric temperature and humidity respectively.They provide very important observations for application in regional and global data assimilation system. Because of the observation instrument accuracy,observation operator approximation,assimilation model limitations, to the assimilating bias needs correction.The significant characteristics of bias effect are to cause systematic increment field,and the increment field could be obtained by OMB（observed minus background） statistic.This bias correction experiment of FY-3A satellite microwave data is developed on the basis of Harris and Kelley＇s bias correction experience method for TOVS radiation data,and with combination of improved WRF-3DVAR system. By analyzing the algorithmic method of radiative transfer in the spectral of microwave coverage,mapping function of model variables and brightness temperature of satellite microwave channel is established,making the fast radiative transfer model to be of quasi-linear expression,with considerable accuracy.Under the fast radiative transfer model and its corresponding tangent linear and adjoint model,a direct variational data assimilation system is established in the original assimilation

关 键 词：FY-3A气象卫星 微波探测 偏差订正 直接同化 台风 

分 类 号：P457.8[天文地球—大气科学及气象学]