Radar-rainfall errors and their effect on runoff simulation in Huaihe River basin

Abstract

将雷达测雨数据与分布式水文模型相耦合进行径流过程模拟,分析雷达测雨误差及其径流过程模拟效果,研究雷达测雨误差对径流过程模拟的影响效应.在对淮河流域气象中心业务化的5种淮河流域雷达测雨数据进行误差分析的基础上,采用雷达测雨数据驱动HEC-HMS水文模型,模拟分析淮河息县水文站以上流域2007年7月1-10日强降雨集中期的径流过程.结果表明:利用雷达测雨数据的径流模拟结果与实测资料的模拟结果基本吻合,各种雷达测雨数据误差经过HEC-HMS水文模型传递后,误差明显减小.联合校准法对应的模拟效果最好,过程流量相对误差NBs'和洪峰流量相对误差Z'分别为-20.2%和-13.3%.;Coupling radar-rainfall data with distributed hydrological model was important in improving flood forecast precision and leading time.However,radar-rainfall error propagation in hydrological model largely affected runoff process simulation.In this study,the operational radar-rainfall data,provided by Huaihe River basin Meteorological Center,was analyzed.With HEC-HMS hydrological model input,radar-rainfall data was used to simulate and analyze the runoff process of rainfall concentration period,in the Xixian hydrological station of Huaihe River basin,during July 1 10,2007.The results showed that runoff simulation based on radar-rainfall data was consistent with the simulation based on rain gauge data.The radar-rainfall input error had been decreased obviously after the propagation of the HEC-HMS model.Runoff simulation based on radar-rainfall data by union calibration was the best,whose relative error were-20.2% and-13.3% for flow process and peak flow,respectively.