基于洪水强度的地面雨情信息分析

摘要

对实测流量过程线进行分析，用洪峰前某时刻和洪峰时刻流量值，结合洪水上涨过程线的曲率，可以很好地逼近洪水流量过程线。考虑特定流域内的强降雨型洪水的天气系统所具有的相对稳定性规律，结合洪量和降雨量之间的相关性及分布式水文模型SWAT、DHSVM，利用曲率包含有时间尺度和河道流量变化幅度的特点，从而能够基于洪水强度进行雨情分析。观测试验在新疆天山地带巴音布鲁克盆地开都河发源地的其中一条支流进行，选取两场不同时间尺度、不同强度的洪水进行分析。结果表明：用洪水上涨过程线的曲率逼近的流量过程线能够较为准确地推算出洪水的量级，而对地面雨情的推算结果与实测结果存在一定差距。%According to the river flow changes between a certain time interval, then the curvature we could get. In this paper, we intended to investigate the flood hydrograph. Using flow values before and after the peak traffic time, together with curvature, we could get a good approximation of flow curves. This method took advantage of the feature of curvature contained the time scale and range of variation, in the meanwhile, we should take full consideration the feature that weather system that caused flood remain relative stability in specific watershed, on the other hand, combined with basin experiment and observation in long term, which included correlation between discharge and infiltration of water quantity accumulated of experience in using SWAT, DHSVM long⁃term flood simulation experiment. So we could set up correlation between flood and rainfall. It also established a new method to analyze rainfall magnitude based on flood situation, in other words, the curvature of river flow process, corresponding to a certain level of rainfall level. To test it, experiment proceeded in one of the tributaries of Kaidu River located in Bayanbulak basin, we selected two different time scales which corresponding to two different intensity of floods, The results show that using curvature to approach flow process can accurately infer flood level, but there is a modest gap about rainfall amount between model calculation and actual observation.