To compare the effects of two external forcing on track of typhoon, TWRF(Typhoon WRF) based ensemble experiments are carried out in the case of Typhoon Morako which is the 8th typhoon at Northwest Pacific region in 2009. The two forcing are tropical SST and topography induced thermal and mechanical forcing, respectively. According to the result of numerical experiment for five-day forecast, the effect of mechanical forcing is about two times stronger than thermal forcing on the track error of the typhoon. More case study for other typhoon will be done as a next paper.

Abstract
 1. 서 론
 2. 모델 및 입력자료
 3. 실험 설계
 4. 실험 결과
 5. 결 론
 참 고 문 헌

• 김해동(계명대학교 지구환경학과) | Hae-Dong Kim (The Department of Global Environment, Keimyung University) Corresponding author
• 원성희(기상청 국가태풍센터) | Seong-Hee Won (National Typhoon Center)
• 최기선(기상청 국가태풍센터) | Ki-Seon Choi (National Typhoon Center)
• 박상욱(기상청 국가태풍센터) | Sang-Wook Park (National Typhoon Center)
• 장기호(기상청 국가태풍센터) | Ki-Ho Jang (National Typhoon Center)