Key Techniques and Challenges of Developing Real-Time Flood Forecasting Systems based on the Xin’anjiang Model

Abstract:

The Xin’anjiang (XAJ) model is a semi-distributed conceptual model for use in humid or semi humid regions. The XAJ model is capable of modeling the major components of hydrological cycle including evapotranspiration, runoff and soil moisture. It has been applied to catchments of different scales to study the hydrological processes. In China many real-time flood forecasting systems are based on XAJ model. Although these systems have been successful in terms of flood control and disaster deduction, challenges still exist. Based on the real-time flood forecasting systems we developed for Yangtze River Basin and Pearl River Basin, We will present the challenges and key techniques of application of XAJ model for flood forecasting, including catchment delineation, model parameters estimation for ungauged catchment, leading time precipitation and evapotranspiration estimation as well as real time foresting influenced by hydraulic engineering. We will also present some results of improving the XAJ model by coupling energy balance scheme to better simulate the actual evapotranspiration.