【作者】 张亚萍；

【导师】 程明虎；

【作者基本信息】 南京信息工程大学 ， 大气物理学与大气环境， 2007， 博士

【摘要】 利用“淮河黄河流域暴雨洪水监测预报系统”试验项目和973中国暴雨项目外场试验资料中的合肥新一代天气雷达(ChIna New generation RADar,CINRAD)资料、气象部门和淮河水利委员会(淮委)收集的雨量计资料、淮委收集的蒸发和流量等水文资料,以淠河上游的响洪甸流域和佛子岭流域为研究区域,分别用地面加密雨量计测量的流域面雨量和雷达反演或外推的面雨量作为TOPMODEL(TOPography based hydrological MODEL)降水—径流模型的输入,进行降水-径流模拟和预报研究。研究内容和获得的主要结论有:提出了天气雷达波束阻挡的动态订正方法。以地面雨量计得到的面雨量为标准,利用2003年6月20日01:00GMT~7月12日00:00GMT的合肥新一代天气雷达资料,对分别用波束阻挡动态订正方法和固定的复合平面查找表(文中简称为静态波束阻挡订正)方法得到的雷达反演响洪甸流域面雨量系列进行比较。结果表明,采用动态波束阻挡订正方法进行雷达测量降水的结果好于采用静态波束阻挡订正方法的结果。在常用的相关方法跟踪回波运动的TREC(Tracking Radar Echo by Correlation)技术基础上,发展了基于差分图像的DITREC(Difference Image-based Tracking Radar Echo by Correlation)技术。个例分析表明:DITREC矢量场消除了TREC矢量场中由于回波型的迅速变化导致的一些无序矢量,使得DITREC矢量场的时间连续性和空间连续性好于TREC矢量场。研究了TREC和DITREC径向分量与多普勒径向速度的关系。个例分析表明,不能简单地用多普勒径向速度对TREC和DITREC的性能进行评估。同时,TREC和DITREC矢量的径向分量与多普勒径向速度的偏差,在一定程度上也反映出降水系统移动方向与多普勒雷达观测到的风向的偏差。用加密地面雨量计网测得的面雨量和雷达—雨量计联合测量降水或外推的面雨量作为TOPMODEL水文模型的降水输入进行了两个水库所控制的流域及其中一些子流域的流量模拟和预报研究。个例分析表明:TOPMODEL在所研究的两个流域是适用的,小流域模拟结果对降水输入相当敏感。用外推开始前1小时的雷达1小时累积降水和雨量计测值计算平均校准因子,对外推得到的雨量场进行校准后,可以明显提高外推1小时流域面雨量的精度,对外推2小时流域面雨量的精度也有所提高。小流域洪峰预报的预见期与流域属性和具体的降水过程有关。为了减小洪峰的预报误差,需要特别关注降水是否持续,以及可能的降水量。更多还原

【Abstract】 The rainfall-runoff model TOPMODEL (TOPography based hydrological MODEL) was used to simulate and forecast the runoffs for Xianghongdian and Foziling subcatchments in the upper reaches of Pihe river. Analyses were based on the rain gauge observations and QPE/QPF (Quantitative Precipitation Estimate/Quantitative Precipitation Forecast) results derived from volume scans of HeFei CINRAD (ChIna New generation RADar) reflectivity observations supported by the project of Huaihe/Huanghe Basins Great Rainfall/ Flooding Monitoring System and the China National Key Development Planning Project for Basic Research (called 973 Project), as well as the evaporation and runoff data provided by the Huaihe River Commission of the Ministry of Water Resources, P. R. C. The conclusions are listed as follows:Firstly, a dynamical weather radar beam blockage correction method was presented. By comparing the radar rainfall estimates based on the dynamical method with the estimates based on the beam blockage correction method which using an unique hybrid scan "lookup table" for each radar (called the static method in this paper) using rain gauge mean-areal rainfall measurements from 01:00 GMT 20 June 2003 to 00:00 GMT 12 July 2003 for Xianghongdian subcatchment, it was shown that the radar rainfall estimates derived from the dynamical beam blockage correction method were better than the estimates from the static method.Secondly, a technique named Difference Image-based Tracking Radar Echo by Correlations (DITREC) was developed, in which the difference images from reflectivity image sequences were used to detect echo motion. The technique was compared with the well-known Tracking Radar Echo by Correlations (TREC) by two case studies. It was found that the DITREC can eliminate those erroneous vectors in the TREC caused by rapid changes of reflectivity within the radar patterns, and improve the temporal and spatial continuity of the echo motion velocity field. On the other hand, the TREC radial velocity and DITREC radial velocity versus the Doppler radial velocity were investigated. The results suggested that they are not quite comparable in our cases. In fact, the biases between the Doppler radial and the TREC or DITREC radial might partially reflect the deflection of the movement of the precipitation system to the Doppler radar observations.Thirdly, the rain gauge observations and QPE/QPF mean areal precipitation derived from radar were used for runoff simulation and forecast using a semi-distributed rainfall-runoff model (TOPMODEL) for Xianghongdian and Foziling subcatchments, as well as several watersheds subdivided (called small basins ) from Foziling. It manifested that the TOPMODEL performed well in two research subcatchments, and the simulated results of the small basins were quite sensitive to the precipitation inputs. The QPF results, before and after the mean-field bias adjustment using a multiplicative factor determined based on radar–rain gauge comparisons of the last hour, were compared using rain gauges. Results show that the QPF results after the adjustment were better than the QPF results before the adjustment. Moreover, the forecast lead times for peak discharge of small basins are related to basin attributes and specific precipitation events. In order to reduce the prediction errors of peak discharge, it is particularly necessary to concern whether the precipitation will persist and the rainfall magnitude in the subsequent hour.更多还原