This study analyzes the correlation between Western Pacific (WP) teleconnection pattern index (WPI) in April during 1954-2008 and rainfall amounts in the same month. Based on the results, it is identified that there have been strong positive correlations between central China, Korea and the southwestern part of Japan in the East Asian region.
Through differences between 10 positive WP years and 10 negative WP years selected from the April WPI excluding ENSO years, it is found that rainfall amounts increase in April of positive WP years due to the following characteristics. Increases in rainfall amounts are evident in the East Asian middle latitudinal region where the positive correlation between the two variables is the highest and this is because anomalous southwesterlies are strengthened in the East Asian middle latitudinal region due to the spatial pattern of a south-low-north-high anomalous pressure system centered on this region that is made by anomalous anticyclones centered on the southeastern side of the region and other anomalous anticyclones centered on the northeastern side of the region. In addition, anomalous westerlies (jet) are strengthen in the upper troposphere of the East Asian middle latitudinal region and as a result, anomalous upward flows are strengthened in this region and thus anomalous warm air temperatures are formed in the entire level of the troposphere in the region. In addition to atmospheric environments, anomalous warm sea surface temperatures are formed in the seas in the East Asian middle latitudinal region to help the rainfall amount increases in the East Asian middle latitudinal region.

Abstract
 1. 서 론
 2. 자료 및 분석방법
  2.1. 자료
  2.2. 분석방법
 3. 서태평양 원격패턴 지수와 4월 강수량 사이의 상관
 4. 서태평양 원격패턴에의 변화에 따른 특징
  4.1. 4월 강수량 공간분포
  4.2. 한국에서 강수량의 연내변동
  4.3. 종관환경
  4.4. 해수면 온도
 5. 요약 및 결론
 REFERENCE

• 최재원(국립기상연구소 정책연구과) | Choi Jae-Won (Policy Research Department, National Institute of Meteorological Research) Corresponding author
• 박기준(국립기상연구소 정책연구과) | Ki-Jun Park (Policy Research Department, National Institute of Meteorological Research)
• 이경미(국립기상연구소 정책연구과) | Kyungmi Lee (Policy Research Department, National Institute of Meteorological Research)
• 김정윤(국립기상연구소 정책연구과) | Jeoung-Yun Kim (Policy Research Department, National Institute of Meteorological Research)
• 김백조(국립기상연구소 정책연구과) | Baek-Jo Kim (Policy Research Department, National Institute of Meteorological Research)