基于雷达外推的城市内涝实时预警

Research on real time urban flooding warning base on radar extrapolation

摘要:

为提高城市内涝实时预警的预见期,提出一种基于雷达技术的城市内涝实时预警模拟方法.该方法通过雷达外推预测未来时刻雷达基本反射率,并将降雨量与雷达基本反射率的相关公式（Z-R关系）优化后用于降雨定量估算,获得未来时刻降雨量,最终以预测降雨为输入运用水力模型实时模拟得到未来时刻的内涝积水分布,进而实现城市内涝的实时预警.结果表明:基于雷达技术的城市内涝实时预警可以获得较为精确的内涝积水分布,并且保留了50 min以上预见期.与传统雨量计实时模拟方法相比,预见期可提高5～25 min,为防汛部门预留了更长的调度指挥时间.该方法以雷达预测的降雨空间分布为输入进行模拟,与雨量计的单点输入方式相比,充分考虑了降雨空间分布这一因素.

Abstract:

To improve the forecast period of real-time urban flooding warning, a real time warning simulation method based on radar technology was proposed. The base reflectivity of feature time was predicted and the optimized Z-R relationship was used to compute rainfall. Then the rainfall in the future was obtained and taken as an input in the hydraulic model. By real time simulation, the urban flooding in the feature was obtained and the urban flooding real time warning was realized. The result shows that urban flooding distribution can be obtained through the urban flooding real time warning based on radar technique, and more than 50 minutes’ forecast period can be saved. Compared with rain gage-based real time simulation, the length of forecast period can be reduced by 5-25 minutes, thus more time was provided for flood prevention department. The rainfall spatial distribution was taken as input in this method. Compared with rain gage input, rainfall spatial distribution was taken into full consideration.