Investigation on the Impact of Agricultural Water Use to the Benefit and Risk of Regional Water Supply under Climate Change
|關鍵字:||區域水資源;系統動力學;氣候變遷;Regional Water Resource;System Dynamic;Climate Change|
Owing to the global climate change, the extreme shortage events occur more frequently then ever and the water shortage risk is increasing. The traditional analysis of water supply risk focused on evaluating the long-term system performance. However, the study may not resolve the general concern on water supply. People concern more on the water shortage in extreme hydrological condition such as dry or flood season then just an average system performance. Hence, this study analyzes the water shortage risk in extreme hydrological condition under global climate change, such as water deficit in dry season and shortage caused by high turbidity in reservoir. The study began at downscaling the Global Climate Chang Model (GCM) data to local (Shihmen Reservoir watershed) basin rainfall. Multiple rainfall data were then synthesized. GWLF model was used to transfer the rainfall into basin runoff. The runoff is the input to the water allocation model developed by using system dynamics method. Base on the synthesized data and water allocation model, this study applied Monte Carlo simulation to analyze water shortage risk analysis during dry season. Moreover, because the reservoir storage can always fufill demands during flood, the water supply simulation can be simplified by considering only the reservoir turbidity and water treatment plant capacity during flood. Since some of the turbidity observations data were missed, an Artificial Neural Network (ANN) was trained to interpolate the missing data in six typhoons. The amount of water supply in high turbidity was simulated using system dynamic and its risk was determined by the occurring probability of the associated typhoon events. The analysis of system performance in dry season and high turbidity condition can be a valuable reference for the sustainable management of Shimmen Reservoir.