Development and application of GIS based K-DRUM for flood runoff simulation using radar rainfall

The aim of this paper is to develop a physical based distributed runoff model for flood simulation considering spatially and temporally varied rainfall and to evaluate the feasibility of an offline mode under typhoon and convective storm events for Korean watershed. Additionally, an auto-calibration method for initial soil moisture conditions that have an effect on discharge was proposed, and Namgang watershed (2,293 km2) was applied as study site. Distributed rainfall according to grid resolution was generated by using a pre-process program of radar rainfall from the JNI radar. Also, GIS hydrological parameters were extracted from basic GIS data such as DEM, land cover and soil map, and used as input data of the model. The Namgang watershed was divided into square grids of 500 m resolution and calculated by kinematic wave into an outlet through channel networks to evaluate capability of the developed model.

► The aim of this paper is to develop a physical based distributed runoff model.
► Also, an auto-calibration method for initial soil moisture conditions was proposed.
► GIS hydrological parameters were used as input data of the model.
► The Namgang watershed was divided into square grids of 500 m resolution.
► The calculation results showed a good agreement with the observed data.