Application of similarity analysis to flood forecasting

[Objective] There are plenty of useful information in hydrological observations. Predicting future flood on the basis of similarity information in historical records is an effective and promising approach. [Method] In this paper, a multi-measure similarity analysis method of rainstorms is developed based on “quantity”, “type” similarity indicators, the earth mover’s distance (EMD) and the rainstorm distribution similarity indicator. Search the similar rainstorm and its corresponding typical flood in historical library and then scale the typical flood process according to the ratio of rainfall amounts to achieve flood forecasting. [Result] The method is applied to a case study in Xinmiao station of Kuye River. The results show that with the accelerating information of rainstorm and flood process, the forecasted flood process is updated continuously, and the prediction accuracy is gradually increasing. [Conclusion] The proposed similarity analysis method is effective and applicable to flood forecasting