Application Of GIUH Based On DEM

Geomorphological instantaneous unit hydrograph (GIUH) is a new basin hydrological runoff model which is developed in these years. Its main advantage is quantificationally introducing the geomorphological element into basin response and little relying to gauged data. Therefore it is suitable for hydrological modeling in ungauged basin. With the GIUH theory growing up, the hydrological model for ungauged basin will be supported well.This paper reviews the development of GIUH in last twenty years and introduces the derivation of the expression in three classes river network, four and five classes river network. The general expression of GIUH is introduced follow. On the other hand, with the developing of the geographic information system (GIS) and digital evaluation model (DEM), it is possible to extract geomorphologic parameters from digital terrain. Then this paper shows the methods of extracting the parameters from grid DEM in detail and discusses some problems when applying GIUH in real basin. By comparing the difference between the net rain and network incoming flow, GIUH and Xin'anjiang coupling model is given. Simulated some historical flood in some basins, and comparing with the actual measurement, the results indicate that the GIUH is feasible for flood prediction and flood serial modeling.