台灣地表與地下水文極端事件發生頻率 變化之研究

Global climate change has led to changes in the frequency and pattern of extreme hydrological events in different regions. Taiwan has been affected by climate change since the 1960s, leading to increasing flood intensity especially in recent years. Changes in precipitation pattern and frequency increase the challenge of water use and affect crop growth and livelihood water supply. This study explores the impact of climate change on the response of the hydrological system in Taiwan. The threshold of 90% and 10% in cumulative distribution function are defined as the severity index of extremely high and extremely low hydrological events, respectively. Considering the frequency and intensity of extreme event, the impact of climate change on water resources is assessed. Analysis are applied to areas in the northern, central and southern Taiwan that are less affected by human interference. The results show that groundwater resource is abundant in northern Taiwan. Extremely high severity in streamflow appears in northern and southern Taiwan. Therefore, the hydraulic structures needs be sustainable under the flood condition. Groundwater serves as a more reliable water resource than streamflow in the dry period. The analysis for the correlation between hydrological components shows that streamflow quickly responses to precipitation. Therefore, flood control needs to be proceeded with precipitation observation at the same time. Groundwater has the delay effect of the extreme precipitation to serve as an emergent water resource under the impact of the climate change.