Stochastic simulation of daily runoff in the middle reaches of the Yangtze river based on SVM-Copula model.

Hydrological stochastic simulation is an important method for hydrologic analysis which needs a large amount of measured data to determine the variable distribution function. That impedes the development of the random simulation in small sample cases. The characteristics of daily runoff series in the middle reaches of Yangtze River has changed a lot since the Three Gorges dam was built in 2003. The measured hydrologic data since 2003 is insufficient for stochastic simulation with conventional methods. In order to overcome the difficulty, a simulation model coupling the support vector machine with the Copula function was established in this paper. The measured data of Hankou Hydrology Station from 2003 to 2015 was used as an applied example to verify the applicability of the model. The research showed that the model we established can maintain the statistical characteristics of the original daily runoff series well, it could be a new way for the random simulation in the case of insufficient data. [ABSTRACT FROM AUTHOR]