Abstract
A distributed biosphere hydrological model with energy balance based multilayer snow physics (WEB-DHM-S) was implemented to investigate the hydrologic response of the current dam operation system to future climate in a snowy river basin (Yattajima basin) of Japan considering the impacts on flood, drought and dam behavior. Dynamic downscaled data (6 km and hourly) for past and future climate were archived from Data Integration and Analysis System (DIAS). Dam operation modules for 6 dams were formulated based on observed patterns of dam inflow/outflow and were validated in 2001-2005. The climatological average analysis of past (1981-2010) vs future (2081-2110) simulation results indicate that a remarkable decrease in runoff in May at Yagisawa, Naramata, Fujiwara and Aimata dam is observed due to shift of snowmelt towards April. Top 20 flood analysis reveals that future peak flow will increase in all gauges and dams except Fujiwara dam. Flood risk is reduced by Fujiwara dam due to the projected changes in snow seasonality. Future low flow will increase reducing the likeliness of the drought; however the number of days with low water level in Yagisawa dam will certainly increase in future.
