抄録
We have compared differences in hydrological simulation results when two different types of bias correction methodologies were applied to general circulation model output. The methodologies are: (1) a shifting-and-scaling method and (2) a quantile mapping method. Similar seasonal variations of 30-year-mean river discharge were obtained for the both bias correction methods. However, for the maximum monthly discharge in 30 years, the shifting-and-scaling method tends to produce larger values than the quantile mapping method. This feature attributes characteristics on multiplication factors for producing future precipitation data: The maximum end of a precipitation range is selectively affected by the factor. This feature might overestimate future risks of flooding. Since future projection of the river discharge directly links to evaluation of risks accompanied with future climate changes, we should pay attention to bias correction methods when we interpret hydrological simulation results.
