ASSESSMENT OF TURBIDITY CHANGE IN RESERVOIRS UNDER FUTURE CLIMATE CHANGE IN JAPAN

Abstract

 In recent years torrential downpour occurs frequently due to the effect of climate change. Because of this, excess of high turbidity in reservoirs and long term persistence of turbidity has recently been regarded as a serious problem. Behaviour of suspended sediment(SS) is highly influenced by characteristics of reservoirs and of its catchments, such as turn over rate and erosion severity. Hence, this study conducted future prediction of turbidity in 29 reservoirs in Japan by applying 1-dimension hydraulic model. Results showed that change in stratification period causes increase of SS concentration in outflow during snowmelt period. Furthermore, we revealed that change in inflow due to change in precipitation will result in substantial increase in SS in outflow in the future.