基于微波成像仪资料反演陆面降水

为了探讨微波亮温与降水的关系,结合时空匹配较好的TRMM卫星测雨雷达(PR)、微波成像仪(TMI)资料,用逐步回归方法,建立统计反演降水的新算式,并对新算式反演结果进行验证.结果表明:对0.1～3 mm/h和3～6 mm/h的降水来说.新算式反演结果与PR雷达反演降水相关较好;对6～10 mm/h的降水来说,新算式反演结果与PR雷达反演降水相关较差;对于大于10 mm/h的降水,新算式反演结果与PR雷达反演降水有较好的相关性,但均方根误差比较大,说明用这种方法反演降水,对于强降水中心的确定有很好的参考价值,但反演结果较实际偏小.通过对2004年7月18日发生的一次特大降水反演结果表明,卫星反演雨带的空间分布、强降水中心位置与PR雷达反演降水以及地基雷达反演降水基本一致.

Retrieval of Precipitation over Land Using Microwave Imagers

In order to study the connection of microwave brightness temperature and precipitation, a new statistical retrieval algorithm is built by the stepwise regression method with well matched precipitation radar (PR) data and TMI brightness temperatures data. The results show that for the precipitation of 0.1 to 3 mm/h and 3 to 6 mm/h, the retrieved results correlate well with the retrieved precipitation from PR radar; for precipitation of 6 to 10 mm/h, the correlation is poor; and for precipitation over 10 mm/h, the correlation is well, but the root mean square error is big, which means that the method can be used to predict strong rainfall centers with smaller retrieved values. With the method, the heavy rainfall process happened on 18 July 2004 is successfully retrieved. The results show that the spatial distribution of the rain belt and the location of the strong rainfall center are consistent with the retrieved precipitation from PR radar and Doppler radar.