In this study, estimation methods for actual evapotranspiration have been studied using the concept of potential and actual evapotranspiration. Among the diverse estimation methods, SWAT-K application is chosen for hydrological modeling. For Jeju island we have characterized annual and monthly evapotranspiration using SWAT-K. In the results, simulated potential evapotranspiration reached to the 91% of small pan evaporation. With respect to the temperature lapse rate(-6 ℃/km) depending on the altitude of Halla mountain, evapotranspiration rate decreased by 7.5% compared to the status when the temperature data from the Jeju weather station were applied to the watershed. As the average of annual rainfall increased, potential evapotranspiration was increased, actual evapotranspiration was, however, decreased.

Abstract
 1. 서 론
 2. 연구재료 및 방법
  2.1. 잠재증발산 및 기준작물증발산
  2.2. 잠재증발산과 실제증발산의 개념 및 관계
  2.3. 유역의 실제증발산 추정방법
  2.4. 유역의 실제증발산 추정절차
  2.5. 대상유역 및 모형구축 현황
 3. 결과 및 고찰
  3.1. 잠재증발산량 모의결과 검증
  3.2. 잠재 및 실제 증발산량 모의결과 분석
 4. 결 론
 참 고 문 헌

• 김남원(한국건설기술연구원 수자원연구실) | Nam Won Kim (Water Resources Research Division, Korea Institute of Construction Technology)
• 이정은(한국건설기술연구원 수자원연구실) | Jeong Eun Lee (Water Resources Research Division, Korea Institute of Construction Technology) Corresponding author