Rainfall Characteristics of the Madden-Julian Oscillation from TRMM Precipitation Radar: Convective and Stratiform Rain

TRMM 자료로 분석한 매든-줄리안 진동의 대류성 및 층운형 강수 특징

  • Son, Jun-Hyeok (Division of Earth Environmental System, Department of Atmospheric Sciences, Pusan National University) ;
  • Seo, Kyong-Hwan (Division of Earth Environmental System, Department of Atmospheric Sciences, Pusan National University)
  • 손준혁 (부산대학교 지구환경시스템학부 대기환경과학과) ;
  • 서경환 (부산대학교 지구환경시스템학부 대기환경과학과)
  • Received : 2010.06.09
  • Accepted : 2010.08.19
  • Published : 2010.09.30

Abstract

The stratiform rain fraction is investigated in the tropical boreal winter Madden-Julian oscillation (MJO) and summer intraseasonal oscillation (ISO) using Tropical Rainfall Measuring Mission (TRMM) Precipitation Rader data for the 11-yr period from 1998 to 2008. Composite analysis shows that the MJO/ISO produces larger stratiform rain rate than convective rain rate for nearly all phases following the propagating MJO/ISO deep clouds, with the greatest stratiform rainfall amount when the MJO/ISO center is located over the central-eastern Indian Ocean and the western Pacific. The fraction of the intraseasonally filtered stratiform rainfall compared to total rainfall (i.e., convective plus stratiform rainfall) amounts to 53~56%, which is 13~16% larger than the stratiform rain fraction estimated for the same data on seasonal-to-annual time scales by Schumacher and Houze. This indicates that the MJO/ISO exhibits the organized rainfall process which is characterized by the shallow convection/heating at the incipient phase and the subsequent flare-up of strong deep convection, followed by the development of stratiform clouds at the upper troposphere.

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