Abstract:In this paper, an algorithm for improving the radarbased quantitative precipitation estimation (QPE) for orographic typhoon precipitation through vertical profiles of reflectivity (VPR) correction is developed. With this method the optimal ground reflectivity and the optimal ZR relationship are obtained simultaneously by the iterative solution of the objective function (the global and regional optimal fitting of VPR). The vertical rainfall structure characteristics and the increase of rainfall in the complex terrain region are fully considered and well corrected. Three typical typhoon cases are selected to verify the accuracy of this newly established method. The results show that the algorithm can display nonuniform VPR characteristics of the different regions of the ocean, plain and complex terrain region, being consistent with the observed structure of the lowlayer precipitation clouds. Compared with other ZR estimation algorithms, this improved scheme could better improve QPE in the complex terrain region. The correlation coefficient between the rainfall estimated by the new algorithm and the rain gauge observations is as high as 0.85-0.94 and the estimation error is reduced by 50% or so.