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采用MM5数值预报模式,以及以MM5和它的伴随模式为基础的四维变分同化系统,以NCEP/NCAR再分析资料为背景场,运用BDA(bogus data assimilation)方案优化热带气旋的初始结构,从而一定程度上弥补了海洋上资料缺乏所造成的台风中心位置不准确,台风环流偏弱,台风内部结构不完整等问题,在此基础上对台风进行了72小时数值预报.通过对多个台风个例的研究表明,BDA方案对台风的初始化处理,有效性地构造出了原来分析场所缺乏的台风内部结构,并且与模式初始场协调,因而大大改进了台风中心强度的预报,对于台风路径的预报也有改进,但不是十分理想,还有待提高.“,”The MM5 and its four dimensional variational data assimilation (4D-Var) system are used in thispaper. Based on the National Centers for Environmental Prediction/National Center for AtmosphericResearch (NCEP/NCAR) reanalysis data, the authors generate an optimal initial condition for a typhoonby using the bogus data assimilation (BDA) scheme. BDA is able to recover many of the structuralfeatures of typhoons including a warm-core vertex, the correct center position, and the strong circulation.As a result of BDA using a bogus surface low, dramatic improvement is achieved in the 72 h predictionof typhoon Herb. Through several cases, the initialization by BDA effectively generates the harmoniousinner structure of the typhoon, but which is lacking in the original analysis field. Therefore the intensityforecast is improved greatly. Some improvements are made in the track forecast, but more work still needsto be done.