在水文循環過程中，蒸發散對於區域性水資源評估及管理是相當中重要的水文因子。本研究計畫延伸「台灣地區區域化蒸發散量參數之評估(1/2)」(NSC-96-2221-E041-016)，以廣泛被應用的Penman-Monteith方法為基準，來推估蒸發皿係數，尋求較簡便之計算方式進而建立台灣蒸發皿修正係數之分布圖，以利推估出真實蒸發散的分布圖，並探討蒸發皿係數之區域空間分布。另外，探討前人發展之蒸發皿係數(Kpan)經驗式並利用Penman-Monteith法與蒸發皿(Epan)之比值( )來進行實際蒸發皿係數之評估比較。本研究利用統計指標分析上述兩種蒸發皿係數方式所評估的蒸發散量之差異，並評估台彎地區區域化的蒸發散量，以期尋求較簡單之經驗方程式解決氣候參數資料之不足等問題。 Evapotranspiration (ET) is an important component of hydrologic budgets, as well as plays an active role in the regional water resources assessment and management. The purpose of this study is to use the meteorological data to estimate the regional reference evapotranspiration and to assess the spatial distribution maps of pan coefficient (Kp) in study area. In addition, five empirical equations of pan coefficient by previous researches are applied to estimate the regional reference evapotranspiration. Moreover, In order to improve the absence of climatic data and to confirm the applicability of five empirical equations, results of empirical equations of pan coefficient compared with the ratio of Penman-Monteith combined method (ET) and pan evaporation (ETpan) recorded (Kp = ET / Epan). Finally, the differences of two methods are calculated by statistical analysis.
