IDENTIFYING GAPS AND OPPORTUNITIES BETWEEN STATISTICAL AND DYNAMICAL DOWNSCALING APPROACHES OVER SHIKOKU ISLAND, JAPAN

Mohamed RASMY, Cho TANDA, Patricia Ann JARANILLA-SANCHEZ, Toshio KOIKE, Masayuki HARA, Mikiko FUJITA, Hiroaki KAWASE
2013 Journal of Japan Society of Civil Engineers Ser B1 (Hydraulic Engineering)  
Downscaling plays a major role in evaluating future changes of precipitation and setting up appropriate adaptation strategies at r egional and local scale. Hence, this study evaluates statis tical bias correction and Dynamical Downs caling ( DD) approaches by applying them to reproduce present climate of precipitation and discharges in Shikoku Island, Japan. DD captured well spatial and temporal distributions of precipitation owing to influence of the spatial resolution enhancement. Statistical
more » ... bias correction has limitations in estimating extreme rainfall intensity as well as frequency with seasonal consistency. In particular, bias corrected GCMs failed to reproduce extreme rainfall events and corresponding discharges in July and August. This is a limitation from the statistical bias correction. As DD results were reasonable with observation, the inconsistency resulted in bias correction method can be eliminated by performing Pseudo Global Warming Down-Scaling (PGW-DS) for future climate. The identified systematic biases in DD will be corrected by statistical method and transferred to PGW-DS. This method aims to provide better science-based information of future changes of precipitation and discharges.
doi:10.2208/jscejhe.69.i_133 fatcat:2exatomm25dkdjv2yzrja42u4u