應用HSPF模式探討降雨時間分佈對流量模擬之影響

Applying the HSPF Model to Evaluate the Effects of Seasonal Variability of Rainfall on Water Flow Simulation

張嘉玲(Chia-Ling Chang) ； 吳天佑(Tain-You Wu)

《農業工程學報》 59卷2期 (2013/06) Pp. 82-91

https://doi.org/10.29974/JTAE.201306_59(2).0005

摘要

近年來全球氣候轉變劇烈，接連出現的災害頻傳都讓人人心惶惶，一下子是出現缺水、限水的情況，一下子卻是出現水庫處於高水位必須洩洪的窘境，這都顯示著台灣各地區水資源時空分配不均的嚴峻，更突顯了台灣可利用的水資源不足之情況。為改善台灣可利用水資源不足之情況，瞭解降雨特性對流量反應的影響是相當重要的工作，故本研究特採用HSPF模式，先進行2007年氣象資料對HSPF參數之率定，再以2008年氣象資料對HSPF參數之驗證，接著以此率定驗證後之參數進行一系列的降雨特性情境設計及分析，降雨型態之情境設計包括：雨量平均型、雨量集中型兩大類。從本研究情境設計所得之分析結果，可得知當降雨時間分佈均勻，可以大幅降低洪峰流量，反之，降雨時間分佈不均，洪峰流量可能會是平均型降雨的上百倍之多。台灣降雨分布不均的狀況相當顯著，每年主要降雨大約僅落在5-10天之間，這也使台灣水資源管理的困難變得更為嚴峻。

關鍵字

流量模擬 ； 模式分析 ； 降雨特性

並列摘要

There are huge changes occurring in our global climate. These changes have caused significant problems for Taiwan, such as sudden water shortages, water restrictions, or reservoirs with water levels that are dangerously high. These examples show some of the major problems in Taiwan's water supply management system. This study applied the HSPF model to assess the influence of seasonal variability of rainfall on surface runoff. The precipitation data for 2007 was used as model calibration and for 2008 it was used as model validation. This study designed several scenarios. Each scenario represents a different seasonal distribution of rainfall. This seasonal rainfall can be represented as uniform or centralized rainfall and, as such, will result in different hydrologic responses. The results show that peak flow will be extremely low when the seasonal distribution of rainfall is uniform. On the contrary, centralized rainfall can cause dramatic peak flow and increase the risk of flooding. Amazingly, most rainfall in Taiwan is centralized in 5 to 10 days. The seasonal variability of rainfall clearly has an unequal and detrimental influence on Taiwan's water supply.

並列關鍵字

flow simulation ； modeling analysis ； rainfall property