一种可用于登陆台风定量降水估计(QPE)方法的初步建立

A PRELIMINARY STUDY ON METHOD OF QUANTITATIVE PRECIPITATION ESTIMATION(QPE) FOR LANDFALL TYPHOON

借鉴Adler-Negri[1]、Goldenberg等[2]及李俊等[3]的工作,通过对三者工作的有机结合及完善,针对登陆台风GMS-5 IR1TBB特征及逐时观测雨量强度及水平分布特点,初步建立一种可用于登陆台风的定量降水估计(QPE)方法,并结合0104号登陆台风“尤特”个例,从各站点逐时雨量、过程雨量以及区域面雨量角度,分析检验了初步建立的云估计降水方法的定量估计能力。结果表明:(1)所建QPE方法可以反映出登陆台风逐时降水的水平分布不均匀性,可以分离出对流降水和层云降水,但对大于15.0 mm/h的降水强度估计能力有限。(2)51.7%的站点过程雨量相对误差小于20%,过程雨量相对误差小于40%的站点数占总站点数的75.9%,表明所建QPE方法对过程雨量的估计能力还是相当强的,这也间接反映了其对逐时雨量较强的估计能力。(3)所建QPE方法对逐时面雨量也具有一定的估计能力,可以为抗旱、防洪决策服务提供一定的参考。

Drawing on the experiences of Adler-Negri,Goldenberg etc. al and Lijun etc. al with perfection, and combining GMS-5 IR1 TBB characteristics of landfall typhoon as well as hourly precipitation intensity and horizontal distribution feature, a preliminary method of quantitative precipitation estimation （QPE） for landfall typhoon was found. On the basis of 0104 landfall typhoon Utor, the ability of quantitative estimation of the preliminary QPE method was examined in the context of hourly, process and area rainfall. The results show that： （1） The QPE method could reflect the horizontal nonuniform distribution of landfall typhoon hourly precipitation and isolate convective and stratum rainfall, however, the ability of estimating strong precipitation over 15mm/h was limited. （2） The process rainfall relative error of 57% stations lower than 20%, and 75. 9 % smaller than 40%, indicated that the ability of the QPE method to estimate process rainfall was significant, which reflected indirectly its ability to estimate hourly precipitation. （3） The QPE method could estimate hourly area rainfall on some degree, which severed as a reference to defend dry and flood.