用变分方法校准天气雷达测定区域降水量的数值计算和精度分析

DIGITIZED CALCULUS AND ACCURACY ANALYSES OF AREA PRECIPITION MEASUREMENT BY WEATHER RADAR WITH CALCULUS OF VARIATIONS FOR ADJUSTMENT

本文应用武汉地区1987年5月25日和5月12日二次降水过程的WSR—81S型数字化雷达的彩色分层数字资料和自动雨量计校准子系统的雨量资料。分别用变分方法和平均校准方法去校准雷达测定区域降水量,并对这两种方法进行比较,发现变分校准技术的效果最佳,能够达到一定的精度。同时介绍了变分方程的数值解法及其权重系数的选择,分析比较了Column Max和ZPPI两种图像数字资料的使用效果。

Two precipition processes happend on may 25, may 12, 1987 in Wuhan region are analyzed quantitatively in this paper by using the digitized data of colorized of the WSR-815 Weather radar and the rainfall of auto-raingauges Which are a part of the Whole radar-raingauge system. It is found that the effect of calculus of variations for adjustment is the most excellent and reached the needed accuracy after adjusting the radar measured area precipitaton with the calculus of variat-, ions and the average adjustment and comparing the two methods. At the same time this paper describes the digital solution of the variation equation and the choice of its weighhted coefficient, analyses and compares the practical effect of the digital information of Column Wax and ZPPI.