氣候變遷對水資源之衝擊評估－以牡丹水庫為例

Impact and Assessment on Climate Change to Water Resources in Watershed of Mudan Reservoir

林旭信(Shiu-Shin Lin) ； 陳立偉(Li-Wei Chen) ； 甘秉玄(Ping-Shiuan Kan)

《先進工程學刊》 7卷2期 (2012/04) Pp. 71-79

https://doi.org/10.29948/JAE.201204.0003

摘要

氣候變遷之影響層面相當廣泛，因此為了瞭解氣候變遷對水資源之影響，本研究以牡丹水庫集水區作為研究案例，使用動力降尺度模式模擬之未來氣候資料，以水文模式模擬水庫集水區入流量，探討未來在氣候變遷情境下（A2、B2）之水資源衝擊評估。本研究首先蒐集恆春氣象站（1897年至2007年）之氣象資料、牡丹雨量站（1998年至2007年）之雨量資料與牡丹水庫實際觀測入流量（1998年至2007年），以Mann-Kendall法針對所使用之氣象資料進行初步趨勢分析，並選用HSPF（Hydrological Simulation Program Fortran）建立牡丹水庫集水區之水文模式，依據牡丹水庫入流量進行參數率定。未來氣候資料則使用動力降尺度模式RSM（Regional Spectral Model）模擬之，最後將資料輸入至率定完成之HSPF中以進行流量衝擊評估。經初步歷史資料檢定發現雨量與蒸發散量無明顯增加或減少，輻射量與露點溫度則有減少趨勢，溫度則有增加之趨勢，並針對雨量資料進行機率分佈檢定，結果顯示未來降雨型態是有改變的。未來氣候變遷條件下水庫入流量評估結果顯示：中期（2040年至2050年）之平均年流量將減少18%（A2情境）、17%（B2情境），平均豐水期之流量減少，平均枯水期之流量增加；長期（2090年至2100年）之平均年流量減少3%（A2情境）、7.9%（B2情境），平均豐水期之流量減少，平均枯水期之流量增加。

關鍵字

氣候變遷 ； 動力降尺度 ； Mann-Kendall檢定 ； HSPF ； RSM

並列摘要

Influence on climate change is expected to be widespread everywhere in the world. In order to investigate the phenomena of impacts on climate change to water resources, taking Muden reservoir for example, dynamic downscaling method is applied in this study to obtain future meteorological data, and the inflow of Muden reservoir by hydrologic model is then simulated to further estimate the impacts of water resources in the scenario of climate change (A2, B2). As to the procedure, meteorological data, the rainfall and real inflow data, are firstly collected from weather stations in Hengchuen (1897-2007) and Mudan watershed (1998-2007). Next, Mann-Kendall test is used to roughly size up preliminary climate trend, and HSPF (Hydrological Simulation Program Fortran) is chosen to set up hydrologic model, giving adjusted parameters in terms of observational inflow in Mudan watershed. And the future climate data are simulated by dynamic downscaling method and RSM (Regional Spectral Model). At last, these data are taken into calibration by giving parameters in HSPF to assess the impact of flow. From the results of Mann-Kendall trend test, precipitation and evaporation are not apparently biased, and radiation and dew point are negatively biased while temperature is positively biased. In addition, rainfall data are analyzed in probability distribution test, showing that the rainfall type will change in the future and, under the climate change condition, the results of inflow assessment in Muden reservoir indicate that, in 2040-2050, the annual mean inflow will decrease 18% (A2) and 17% (B2) while mean inflow of rainy days will decrease and mean flow of dry days will increase. In 2090-2100, annual mean inflow will decrease 3% (A2) and 7.9% (B2), whereas mean inflow of rainy days will decrease and mean inflow of dry days will increase.

並列關鍵字

climate change ； dynamic downscaling ； Mann-Kendall test ； HSPF ； RSM