Bias correction of RCM output considering frequency distribution

Abstract

This study aims to develop the method for detecting and correcting the bias information of RCMs. This system is designed to be general so that it can follow the change in model setting. Bias information for each individual grid is too much for handling, and some grids may have no evaluation data. Therefore, model bias is evaluated in each river basin or prefecture unit. Not only the monthly mean value, but also frequency distribution is evaluated for each unit area. A new bias correction method that can reproduce the extreme values while keeping the monthly mean value is proposed. In most cases, this new method works well in getting better frequency distribution and extreme values.