Recently, the use of radar rainfall data that can help tracking of the development and movement of
rainfall's spatial distribution is drawing much attention in hydrology. The reliability of existing radar rainfall
compared to gauge rainfall data on the ground has not yet been confirmed and so we have difficulties to apply the
radar rainfall in hydrology. The radar rainfall for the applications in hydrology are adjusted merging method derived
from gage. This study uses the Mean-Field Bias (MFB) and Statistical Objective Analysis (SOA) as correction
methods to create adjusted grid-based radar rainfall data which can represent the temporal and spatial distribution of
rainfall. This study used a storm event occurred in August 2010 for the adjustment of radar rainfall. In addition, the
grid-based distributed rainfall-runoff model (Vflo), which enables more detailed examinations of spatial flux changes
in the basin rather than the lumped hydrological models, has been applied to Gamcheon river basin which is a
tributary of Nakdong River located in south-eastern part of the Korean peninsular and the basin area is 1005km2.
The simulated runoff was compared with the observed runoff in an attempt to evaluate the usability of radar rainfall
data and the reliability of the correction methods. The error range of peak discharge using each correction method
was within 20 percent and the efficiency of the model was between 60 and 80 percent. In particular, the SOA
method showed better results than MFB method. Therefore, the SOA method could be used for the adjustment of
grid-based radar rainfall and the adjusted radar rainfall can be used as an input data of rainfall-runoff models.