A method for real-time flash flood warning based on the critical rainfall of rainfall time history distribution

Abstract

The invention discloses a real-time mountain floodv early warning method based on critical rainfall of rainfall time-history distribution. The rainfall data in a T period before a flood peak appears in each previous flooding process are firstly extracted, and the cumulative rainfall in the T period is calculated; then, a Lorenz curve is constructed based on the rainfall data in the T period beforea flood peak appears, the Gini coefficient of the Lorenz curve is calculated, and based on the Gini coefficient, the rainfall in the T period before the flood peak appears is divided into three types; the tension water content saturation, that is, initial soil water content saturation, at the T time before the flood peak appears is then counted; whether each previous flood is an over-alarm floodis judged, cumulative rainfall-initial soil water content saturation scatter diagrams for rainfall in even, uneven, and concentrated types are made respectively, points corresponding to the over-alarmfloods are marked, and a critical rainfall line is drawn in combination of the points corresponding to the over-alarm floods; and real-time early warning is finally carried out according to the critical rainfall line.

Description

technical field [0001] The invention relates to the technical field of hydrology, in particular to a method for real-time mountain torrent warning based on critical rainfall of rainfall time-history distribution. Background technique [0002] There are many rivers in my country, with a drainage area of ​​200 to 3000 km 2 There are nearly 9,000 small and medium-sized watersheds. In recent years, under the influence of climate change, sudden floods in small and medium rivers caused by local heavy rainfall have occurred frequently, and have become the main disasters causing casualties. Because small and medium-sized watersheds are usually located in remote mountainous areas with complex terrain and steep slopes, rapidly rising floods can easily cause floods that endanger the personal safety and social economy of local residents. Early warning has become an important problem to be solved urgently. [0003] The critical rainfall method is a widely used method for flash flood w...

AI Technical Summary

Problems solved by technology

However, most of the existing methods for deriving critical rainfall do not take into account the time-historical distribution of rainfall.

In fact, for the same amount of rainfall, short and concentrated rainstorms are more likely to produce sudden floods and are therefore more dangerous

If this situation cannot be paid attention to in the process of calculating the critical rainfall, it will often lead to the calculated critical rainfall being too high, and the actual rainfall in the real-time warning of mountain torrents often does not reach the critical rainfall and thus misses the report. Certain hidden dangers

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