地球系統中與人最息息相關的則屬大氣地球科學的部分，在過去研究多著重於探討自然氣候變遷所可能造成之氣象變化，而在近來之研究，已漸漸加入氣候變遷對人為環境所可能影響之區域水文循環與水文環境平衡，氣候變遷除了直接影響地表地下水文循環之外，亦會間接改變區域水文環境。 由歷史資料顯示，水文循環變化除了對降雨量與氣溫發生變化之外也影響著降雨型態的分佈；台灣北部地區歷史資料分析近20年來乾季降雨量逐漸減少，濕季降雨量逐漸增加，且降雨延時變短但平均降雨強度反而增加，相對的導致集水區洪峰流量變大，洪峰流量變大將使得土壤沖刷的情況更加劇烈，土壤中的氮、磷物質更容易沖刷出，使得非點源汙染量的增加，而集水區營養鹽物質的多寡也將影響到集水區優養化的現象。 因此本研究目的在分析前人研究的未來降雨量與氣溫，並且加入降雨型機率的因素，探討過去的降雨機率與未來降雨機率的變化，並以GWLF 水質模式模擬氣候變遷下的集水區水理變化及營養鹽改變情況，探討各個因子受氣候影響之可能性，進而利用可能發生的氣候與環境變遷情境，評估對環境可能造成的衝擊影響，以利未來研擬適當的調適措施，供環境管理者管理水質狀況。 研究結果顯示，台灣北部與中部地區降雨機率變化為不相同的，翡翠水庫降雨機率為越來越集中的趨勢，石門水庫確是越來越分散，而中部濁水溪流域玉峰橋則是呈現連續降雨減少的變化。並且經由數值模擬結果顯示集水區入流量在未來為減低的變化，氮、磷濃度則是增加的趨勢。 The atmosphere studies in the Earth system in the past emphasize possible meteorological changes under natural climate vicissitude. However, recently the researchers attempted to investigate the impact of climate vicissitude to regional circulation of water and the hydrology environment. Climate vicissitude not only affects the direct influence of surface and underground circulation of water, but also indirectly changes the region hydrology environment. Demonstrated by the historical date, it is noted that the circulation of water affects the rainfall amount as well as the temperature. Moreover, it affects the distribution of rainfall condition. In North Taiwan, the local record of the near twenty year shows the rainfall of dry season being gradually decrease, but the rainfall of wet season being gradually increases. The improper land-use changes the carrying capacity of hydrological environment. As a result, water quality deteriorated in an obvious trend. The General Water Load Function (GWLF) model is selected to simulate some scenarios under the impacts of climate changes. Moreover, the study focused on the hydrological factors which affect the water quality and assimilative capacity in Choshui creek basin, where each factors forcing by climate changes. The study draws up applicable tactics and criterions about managing water quality to provide environmental management. The experimental results demonstrate that rainfall pattern, in terms of probability changes differently in Taiwan. In Fetitsui reservoir watershed, the rainfall becomes more concentrated, while in Shihmen reservoir watershed disperser. In Yun-Feng Bridge region, it shows the continuous rainfall slightly reduces. Simulation results of the stream flow decreases, but the nitrogen and phosphorus concentration of the flow shows a tendency of increase.
